tacrolimus and Body-Weight

This review summarises the available data on the population pharmacokinetics of tacrolimus and use of Maximum A Posteriori (MAP) Bayesian estimation to predict tacrolimus exposure and subsequent drug dosage requirements in solid organ transplant recipients. A literature search was conducted which identified 56 studies that assessed the population pharmacokinetics of tacrolimus based on non-linear mixed effects modelling and 14 studies that assessed the predictive performance of MAP Bayesian estimation of tacrolimus area under the plasma concentration-time curve (AUC) from time zero to the end of the dosing interval. Studies were most commonly undertaken in adult kidney transplant recipients and investigated the immediate-release formulation. The pharmacokinetics of tacrolimus were described using one- and two-compartment disposition models with first-order elimination in 61 and 39 % of population pharmacokinetic studies, respectively. Variability in tacrolimus whole blood apparent clearance amongst transplant recipients was most commonly related to cytochrome P450 (CYP) 3A5 genotype (rs776746), patient haematocrit, patient weight, post-operative day and hepatic function (aspartate aminotransferase). Bias, as calculated using estimation of the mean predictive error (MPE) or mean percentage predictive error (MPPE) associated with prediction of the tacrolimus AUC, ranged from -15 to 9.95 %. Imprecision, as calculated through estimation of the root mean squared error (RMSE) or mean absolute prediction error (MAPE), was generally much poorer overall, ranging from 0.81 to 40. r

Topics: Area Under Curve; Bayes Theorem; Body Weight; Cytochrome P-450 CYP3A; Dose-Response Relationship, Drug; Hematocrit; Humans; Immunosuppressive Agents; Kidney Transplantation; Liver Failure; Models, Biological; Organ Transplantation; Tacrolimus

In the last several years, a number of experiments have implicated a pivotal role of the calcium/calmodulin-calcineurin dependent pathway as a final common signaling mechanism by which diverse hypertrophic stimuli converge to mediate hypertrophic responses in cardiomyocytes. Calcineurin inhibitors, i.e. cyclosporine A (CsA) and FK506, can interrupt the pathway, thereby preventing cardiac hypertrophy. The data that convincingly support this novel hypothesis were derived either from in vitro studies in cultured cardiomyocytes or from in vivo studies in transgenic mice. However, when the hypothesis was tested in clinically relevant animal models of cardiac hypertrophy, controversial results and conclusions emerged. In conventional models of cardiac hypertrophy, two questions remain to be answered: (1) whether calcineurin is activated in hypertrophied cardiac muscle, and (2) whether calcineurin inhibitors prevent cardiac hypertrophy. In addition, clinical observations have revealed that calcineurin inhibitors appear to exert pro-hypertrophic effects in organ transplant recipients. The controversies suggest that current calcineurin inhibitors are blunt tools for testing the hypothesis in pressure-overload hypertrophy in vivo, because there are so many confounding effects that are associated with systemic administration of the drugs. As such, new genetic approaches may overcome some of the problems associated with pharmacological inhibitors. This invited review will focus on the controversies surrounding the ability of calcineurin inhibition to prevent conventional (pressure-overload) cardiac hypertrophy and the new genetic approaches to address the question.

Topics: A Kinase Anchor Proteins; Adaptor Proteins, Signal Transducing; Adrenergic beta-Agonists; Animals; Animals, Genetically Modified; Body Weight; Calcineurin; Calcineurin Inhibitors; Carrier Proteins; Cyclosporine; DNA-Binding Proteins; Exercise; Gene Transfer Techniques; Hemodynamics; Humans; Hypertension; Hypertrophy, Left Ventricular; Intracellular Signaling Peptides and Proteins; Isoproterenol; Mice; Models, Animal; Muscle Proteins; Myocardium; Phosphoproteins; Rats; Tacrolimus

Patients expressing the cytochrome P450 (CYP) 3A5 gene require a higher tacrolimus dose to achieve therapeutic exposure compared with nonexpressers. This randomized-controlled study investigated whether adaptation of the tacrolimus starting dose according to CYP3A5 genotype increases the proportion of kidney transplant recipients being within the target tacrolimus predose concentration range (10-15 ng/mL) at first steady-state. Two hundred forty living-donor, renal transplant recipients were assigned to either receive a standard, body-weight-based or a CYP3A5 genotype-based tacrolimus starting dose. At day 3, no difference in the proportion of patients having a tacrolimus exposure within the target range was observed between the standard-dose and genotype-based groups: 37.4% versus 35.6%, respectively; p = 0.79. The proportion of patients with a subtherapeutic (i.e. <10 ng/mL) or a supratherapeutic (i.e. >15 ng/mL) Tac predose concentration in the two groups was also not significantly different. The incidence of acute rejection was comparable between both groups (p = 0.82). Pharmacogenetic adaptation of the tacrolimus starting dose does not increase the number of patients having therapeutic tacrolimus exposure early after transplantation and does not lead to improved clinical outcome in a low immunological risk population.

Topics: Adult; Aged; Body Weight; Cytochrome P-450 CYP3A; Dose-Response Relationship, Drug; Female; Follow-Up Studies; Genotype; Glomerular Filtration Rate; Graft Rejection; Graft Survival; Humans; Immunosuppressive Agents; Kidney Failure, Chronic; Kidney Function Tests; Kidney Transplantation; Living Donors; Male; Middle Aged; Netherlands; Polymorphism, Single Nucleotide; Postoperative Complications; Prevalence; Prognosis; Prospective Studies; Risk Factors; Tacrolimus; Young Adult

Cytomegalovirus (CMV) infection is one of the most common and important opportunistic infections following kidney transplantation. It causes significant morbidity and mortality. Valganciclovir (VGCV) is the drug of choice for prophylaxis to prevent CMV infection.. We conducted a post-hoc analysis of a randomized controlled trial in 187 kidney transplant recipients to evaluate the impact of VGCV dosing and renal function on the development of CMV infection.. The results demonstrate that the following variables were independent risk factors for the development of CMV infection: high-risk CMV serostatus (donor positive/recipient negative; hazard ratio [HR] 1.4, 95% confidence interval [CI] 1.46-5.28, P = 0.002); anti-thymocyte globulin induction therapy (HR 2.1, 95% CI 1.08-4.07, P = 0.028); higher mean tacrolimus trough concentration (HR 1.4, 95% CI 1.09-1.74, P = 0.007); creatinine clearance <60 mL/min (HR 3.4, 95% CI 1.64-6.85, P = 0.001); and body weight >80 kg (HR 2.1, 95% CI 1.05-4.37, P = 0.037). VGCV dosing was appropriate for most patients, in those who did and did not develop CMV infection. These results strongly suggest that the currently recommended dose adjustments of VGCV dosing based on estimated renal function calculated using ideal body weight may underestimate the renal function of overweight patients and indirectly result in underexposure of overweight patients to VGCV. Based on these findings, further VGCV pharmacokinetic analyses are warranted in kidney transplant recipients with moderate-to-severe renal dysfunction.

Topics: Adult; Aged; Antibodies, Viral; Antilymphocyte Serum; Antiviral Agents; Body Weight; Creatinine; Cytomegalovirus; Cytomegalovirus Infections; Disease-Free Survival; Female; Ganciclovir; Humans; Immunosuppressive Agents; Kidney; Kidney Transplantation; Male; Middle Aged; Tacrolimus; Valganciclovir

The objective was to develop a population pharmacokinetic-pharmacogenetic model of mycophenolic acid following administration of mycophenolate mofetil (MMF) in de novo pediatric renal-transplant patients and identify factors that explain variability. The pharmacokinetic samples were collected from 89 de novo pediatric renal-transplant patients treated with MMF and studied during the first 60 postoperative days. All patients were genotyped for UGT1A8-A9, UGT2B7, and ABCC2. Population pharmacokinetic analysis was performed with the NONMEM and was validated using bootstrap visual predictive check. The pharmacokinetic data were best described by a 2-compartment model with Erlang distribution to describe the absorption phase. The covariate analysis identified body weight as an individual factor influencing central volume of distribution and concomitant immunosuppressive medication and identified body weight and UGT2B7 802C>T genotype as individual factors influencing apparent oral clearance (CL/F) of MMF. CL/F in cyclosporine-MMF-treated patients was 33% higher than in tacrolimus-MMF-treated patients. The CL/F was significantly lower in patients with UGT2B7 802 C/C genotype compared with patients with UGT2B7 802 C/T and 802T/T genotypes, and this effect was independent of concomitant immunosuppressive medication or body weight. The population pharmacokinetic-pharmacogenetic model of mycophenolic acid was validated. Body weight, concomitant medication, and UGT2B7 genotype contribute significantly to the interindividual variability of MMF disposition in pediatric renal-transplant patients.

Topics: Adolescent; Body Weight; Child; Child, Preschool; Cyclosporine; Female; Genotype; Glucuronosyltransferase; Humans; Immunosuppressive Agents; Infant; Kidney Transplantation; Male; Models, Biological; Multidrug Resistance-Associated Protein 2; Mycophenolic Acid; Nonlinear Dynamics; Pharmacogenetics; Prospective Studies; Tacrolimus; Tissue Distribution

The aim of this study was to develop a population pharmacokinetic model of tacrolimus in pediatric kidney transplant patients, identify factors that explain variability, and determine dosage regimens. Pharmacokinetic samples were collected from 50 de novo pediatric kidney transplant patients (age 2-18 years) who were on tacrolimus treatment. Population pharmacokinetic analysis of tacrolimus was performed using NONMEM, and the impact of variables (demographic and clinical factors, and CYP3A4-A5, ABCB1, and ABCC2 polymorphisms) was tested. The pharmacokinetic data were described by a two-compartment model that incorporated first-order absorption and lag time. The apparent oral clearance (CL/F) was significantly related to body weight (allometric scaling); in addition, it was higher in patients with low hematocrit levels and lower in patients with CYP3A5*3/*3. The population pharmacokinetic-pharmacogenetic model developed in de novo pediatric kidney transplant patients demonstrated that, in children, tacrolimus dosage should be based on weight, hematocrit levels, and CYP3A5 polymorphism. Individualization of therapy will enable the optimization of tacrolimus exposure, with resultant beneficial effects on kidney function in the initial post-transplantation period.

Topics: Adolescent; Age Factors; ATP Binding Cassette Transporter, Subfamily B; ATP Binding Cassette Transporter, Subfamily B, Member 1; Body Weight; Child; Child, Preschool; Cytochrome P-450 CYP3A; Drug Dosage Calculations; Drug Monitoring; Drug Therapy, Combination; Female; France; Hematocrit; Humans; Immunosuppressive Agents; Kidney Transplantation; Male; Models, Biological; Multidrug Resistance-Associated Protein 2; Multidrug Resistance-Associated Proteins; Polymorphism, Genetic; Reproducibility of Results; Tacrolimus; Treatment Outcome

This study presents the first prospective multicenter study assessing sirolimus-based immunosuppression with early (4-day) corticosteroid withdrawal (CSWD) in renal transplantation. Immunosuppression included: anti-IL-2 receptor antibody and tacrolimus/sirolimus. Inclusion criteria included adult primary recipients. Exclusion criteria included: (i) African Americans, (ii) current PRA >50%, (iii) multiple organ transplants, (iv) WBC < 3000 cells/microL and (v) fasting hypercholesterolemia/hypertriglyceridemia. The primary endpoints were acute rejection and the proportion of patients off corticosteroids. Seventy-seven patients were enrolled: mean age of 49.7 +/- 12 years. Transplants included: cadaveric (26%) and living donor (74%). Patient and graft survival were 100%. Biopsy proven acute rejection occurred in 13%; presumptive rejection in 10.5%. Banff grades included: IA (seven patients), IB (one patient), IIA (one patient) and IIB (one patient). Renal function at 1 year: serum creatinine (1.18 +/- 0.06 mg/dL). Mean weight gain was minimal at 1 year: 3 +/- 2 kg/patient. Mild increases in total, LDL and HDL cholesterol were observed and new antilipid agent use occurred in 26 patients. In conclusion, early CSWD under tacrolimus/sirolimus-based immunosuppression in selected, low-risk renal transplant recipients provides: (i) excellent patient and graft survival, (ii) good renal function, (iii) reduced hyperlipidemia and antilipid agent use and (iv) low acute rejection rates.

Topics: Adrenal Cortex Hormones; Adult; Antibodies, Monoclonal; Basiliximab; Biopsy; Blood Pressure; Body Weight; Cadaver; Cardiovascular System; Cholesterol, HDL; Cholesterol, LDL; Creatinine; Female; Graft Rejection; Graft Survival; Humans; Immunosuppressive Agents; Infections; Kidney Transplantation; Living Donors; Male; Middle Aged; Pilot Projects; Recombinant Fusion Proteins; Risk Factors; Sirolimus; Steroids; Tacrolimus; Time Factors; Treatment Outcome

New-onset diabetes mellitus (NODM) is associated with increased risk of graft failure and death in renal transplant recipients. Some clinical studies have indicated that NODM risk is higher with tacrolimus than cyclosporine, but no comparative trial has used American Diabetic Association (ADA)/World Health Organization (WHO) criteria for diagnosis of diabetes mellitus. The Diabetes Incidence After Renal Transplantation, Neoral C2 Monitoring Versus Tacrolimus (DIRECT) study is a 6-month open-label, multicenter trial comparing the impact of tacrolimus and Neoral (cyclosporine microemulsion) on glucose metabolism in 700 de novo kidney transplant recipients, based on ADA/WHO criteria. Patients are randomized to tacrolimus (C0 monitoring) or Neoral (C2 monitoring), stratified by baseline diabetic status and ethnicity. All patients receive basiliximab, corticosteroids, and mycophenolate mofetil or enteric-coated mycophenolate acid (myfortic). Pooled interim 3-month results from a subset of 115 patients receiving either tacrolimus or Neoral showed that the primary efficacy end-point (biopsy-proven acute rejection [BPAR], graft loss or death) occurred in 11 patients (10%). There were four graft losses and only one death, which occurred after graft loss. Eight patients experienced BPAR (7.3%). Among 99 patients who were nondiabetic at baseline, 14 developed NODM by month 3, 17 developed impaired fasting glucose or impaired glucose tolerance, and another 5 patients received hypoglycemic treatment for at least 14 consecutive days or at the month 3 visit, resulting in a 36% incidence of impaired glucose metabolism. At 3 months, median GFR (Nankivell) was 63.7 mL/min; median serum creatinine was 137 micromol/L. Full complete results are expected in December 2005.

Topics: Adrenal Cortex Hormones; Adult; Body Weight; Cyclosporine; Diabetes Mellitus; Drug Monitoring; Drug Therapy, Combination; Female; Humans; Immunosuppressive Agents; Kidney Transplantation; Male; Middle Aged; Mycophenolic Acid; Reoperation; Tacrolimus; Tissue Donors; Treatment Failure; United States; White People

This study compares the pharmacokinetics of tacrolimus (TAC) and cyclosporine Neoral (CsA) in cardiac transplant recipients.. Twenty-six de novo cardiac recipients were prospectively and randomly assigned to receive oral TAC- or CsA-based regimens after 5 to 6 days of rabbit antithymocyte globulin induction. Blood samples were collected at 0 (before the dose) and 0.5, 1, 2, 3, 4, 6, 8, 10, as well as 12 hours after drug administration. The pharmacokinetics of the first dose (PK-1) and at steady state (PK-S, 1 month after transplantation) were analyzed.. Comparing the AUC per milligram dose, there was no significant difference between PK-1 and PK-S among TAC (46.0 +/- 24.3 ng x h/mg x mL versus 69.0 +/- 43.9 ng x h/mg x mL, P = .15 by paired t-test), but a significant difference in CsA (25.2 +/- 11.4 ng x h/mg x mL versus 45.4 +/- 12.9 ng x h/mg x mL, P = .0005 by paired t-test). This means better TAC absorption in the early post-heart transplant period. Using a single-point blood level to predict AUC, TAC showed a significantly higher correlation than CsA at all corresponding sampling times. Besides, C12 in both PK-1 and PK-S of TAC displayed good correlations to the AUC (r2 = .895, P = .00 in PK-1 and r2 = .81, P = .00 in PK-S). The TAC trough level was accurate enough to predict the AUC.. The pharmacokinetic profile of TAC is more reliable than that of CsA in the early post-heart transplant period. A high correlation of trough blood levels with AUC omits the requirement for a multiple sampling strategy to more accurately measure AUC as is needed with CsA.

Topics: Antilymphocyte Serum; Area Under Curve; Biological Availability; Body Weight; Cyclosporine; Drug Monitoring; Female; Heart Transplantation; Humans; Immunosuppressive Agents; Male; Tacrolimus

Cyclosporine is considered to contribute to the high cardiovascular morbidity and mortality in patients after renal transplantation. Tacrolimus may be more favorable in this respect, but controlled data are scarce. In this prospective randomized study in 124 stable renal transplant patients, the effects of conversion from cyclosporine to tacrolimus on cardiovascular risk factors and renal function were investigated. Follow-up was 6 mo. Statistical analysis was performed by ANOVA for repeated measurements. The serum creatinine level decreased from 137 +/- 30 micromol/L to 131 +/- 29 micromol/L (P < 0.01). Three months after conversion from cyclosporine to tacrolimus, mean BP significantly decreased from 104 +/- 13 to 99 +/- 12 mmHg (P < 0.001). Serum LDL cholesterol decreased from 3.48 +/- 0.80 to 3.11 +/- 0.74 mmol/L (P < 0.001,) and serum apolipoprotein B decreased from 1018 +/- 189 to 935 +/- 174 mg/L (P < 0.001). Serum triglycerides decreased from 2.11 +/- 1.12 to 1.72 +/- 0.94 mmol/L (P < 0.001). In addition, both rate and extent of LDL oxidation were reduced. The fibrinogen level decreased from 3638 +/- 857 to 3417 +/- 751 mg/L (P < 0.05). Plasma homocysteine concentration did not change. Three months after conversion, plasma fasting glucose level temporarily increased from 5.4 +/- 1.3 mmol/L to 5.8 +/- 1.9 mmol/L (P < 0.05). Conversion to tacrolimus resulted in a significant reduction of the Framingham risk score. In conclusion, conversion from cyclosporine to tacrolimus in stable renal transplant patients has a beneficial effect on renal function, BP, serum concentration and atherogenic properties of serum lipids, and fibrinogen.

Topics: Adult; Aged; Analysis of Variance; Apolipoproteins B; Blood Glucose; Blood Pressure; Body Weight; Cardiovascular System; Cholesterol; Cyclosporine; Female; Fibrinogen; Fibrinolysis; Graft Survival; Humans; Immunosuppressive Agents; Kidney; Kidney Transplantation; Lipoproteins, LDL; Male; Middle Aged; Oxygen; Risk Factors; Tacrolimus; Time Factors; Triglycerides

To clarify the incidence and pathophysiological mechanism of cardiovascular adverse effects of tacrolimus, the present prospective study performed scheduled cardiovascular examinations at 1, 2, 4, 8, 16, 20, and 24 weeks after starting the tacrolimus therapy in 68 consecutive kidney transplantation recipients enrolled from 26 institutes in Japan. Patients with previous coronary artery disease or congestive heart failure were excluded. The examinations included any subjective symptoms, changes in resting ECG, ambulatory Holter's dynamic ECG, two-dimensional echocardiography, and monitoring of serum drug concentrations and cardiac troponin T levels. Cardiac nuclear imaging and/or coronary angiography were performed in the case of suspicious coronary events. During the investigation, chest pain in 9 (13.2%) and palpitation in 6 patients (8.8%) were reported, both closely related to elevated blood drug concentrations (37.2 +/- 18.7 ng/mL, mean +/- SD). Cardiovascular examinations detected development of resting ECG abnormalities in 12 patients (17.6%), asymptomatic ST depression following increased heart rate in 11 (16.2%) and ventricular arrhythmias in 7 patients (10.3%) on Holter's dynamic ECG. Elevation of troponin T was detected in 3 patients (4.4%), which was also closely related to elevated drug concentrations and interpreted as myocardial damage associated with the therapy. Assessments by thallium(Tl)-201 myocardial scintigraphy and/or coronary angiography in patients with suspicious coronary events revealed only two patients (2.9%) were considered to be myocardial ischemia associated with coronary vasospasm or microcirculatory disturbance. Sequential evaluations on echocardiography revealed significant (p<0.05) decrease in LV end-diastolic dimension (4, 8, 18 and 24 weeks) and LV end-systolic dimension (from 1 to 24 weeks), and significant (p<0.05) increase in LV ejection fraction 1 to 4 weeks after the kidney transplantation. Thickening of LV wall (>2 mm compared with baseline) was detected in only one patient. The present prospective study detected totally 30.9% incidence of cardiovascular adverse events. Symptomatic events and troponin T elevation were closely related to elevated blood drug concentrations (>20 ng/ml). Coronary vasomotor dysfunction seemed to be related to these adverse events especially when the blood drug concentration was exceeding 20 ng/ml.

Topics: Adolescent; Adult; Body Weight; Cardiomyopathy, Hypertrophic; Cardiovascular Diseases; Dose-Response Relationship, Drug; Echocardiography; Electrocardiography; Electrocardiography, Ambulatory; Female; Humans; Immunosuppressive Agents; Kidney Transplantation; Male; Middle Aged; Prospective Studies; Tacrolimus; Time Factors; Troponin T

Topics: Adult; Body Weight; Bone Density; Cyclosporine; Humans; Immunosuppressive Agents; Kidney Transplantation; Tacrolimus; Time Factors

Black American heart transplant recipients receiving cyclosporine-based primary immunoprophylaxis suffer higher rates of allograft rejection with hemodynamic compromise, infections, and posttransplant coronary artery disease. We examined the hypothesis that a combination of tacrolimus and mycophenolate mofetil "resurrects" clinical outcome of black Americans to those seen in white heart transplant recipients.. Sixty-three adult primary heart transplant recipients were included in this study. Twenty black American and 21 white patients who received tacrolimus-based primary immunoprophylaxis were enrolled in this prospective, observational parallel cohort investigation. A separate group of 22 black American patients were randomly allocated to receive cyclosporine-microemulsion-based primary prophylaxis and served as the control population for assessing outcomes in the black American group. Adjunctive immunosuppression included mycophenolate mofetil and corticosteroids. The primary end-point was the freedom from allograft rejection requiring treatment at 1 year. Secondary end-points included rejection with hemodynamic compromise, and patient or graft survival. Adverse events evaluated included development of infections requiring hospitalization and nonimmunological outcomes including hyperlipidemia, hypertension, and diabetes mellitus (new onset or worsened).. Tacrolimus-treated black American patients had greater freedom from allograft rejection requiring treatment at 1 year than those treated with cyclosporine (64% vs. 37%, P=0.01). No differences were noted between tacrolimus-treated black Americans and whites in the primary end point (64% and 67% respectively, P=nonsignificant [NS]). Tacrolimus-based immunosuppression was associated with better 1-year survival in black Americans compared with cyclosporine (95% vs. 73%, P=0.04), and this end point was similar to that achieved in tacrolimus-treated white heart transplant recipients (95%). No differences in infection rates were noted among either group. Cyclosporine-treated black Americans suffered more hyperlipidemia and worse hypertension than tacrolimus-treated patients.. Compared with cyclosporine, an immunosuppressive strategy using tacrolimus in black Americans achieves superior efficacy with regard to allograft rejection, higher allograft survival, and similar safety. Furthermore, tacrolimus-based immunosuppression is similar in immunological efficacy and safety in black Americans and in white heart transplant recipients.

Topics: Adult; Aged; Black or African American; Black People; Body Weight; Creatinine; Cytomegalovirus Infections; Dose-Response Relationship, Drug; Drug Therapy, Combination; Female; Graft Rejection; Heart Transplantation; Hemodynamics; Humans; Hyperlipidemias; Hypertension; Immunosuppressive Agents; Incidence; Male; Middle Aged; Mycophenolic Acid; Tacrolimus; Transplantation, Homologous; Treatment Outcome; White People

Tacrolimus (FK506, Prograf), marketed for the prophylaxis of organ rejection following allogenic liver or kidney transplantation, is virtually completely metabolized. The major metabolic pathways are P450 3A4-mediated hydroxylation and demethylation. Since P450 hepatic drug-metabolizing enzymes may be impaired in hepatic dysfunction, a study was conducted to characterize oral and intravenous tacrolimus pharmacokinetics in 6 patients with mild hepatic dysfunction and compared with parameters to those from normal subjects obtained in a separate study. Patients received two treatments: a single 0.020 mg/kg ideal body weight (IBW) i.v. dose infused over 4 hours and approximately 0.12 mg/kg IBW orally; normal subjects were dosed at 0.02 mg/kg 4-hour i.v. and 5 mg (0.065 mg/kg) p.o. Mean blood pharmacokinetic parameters with mild hepatic dysfunction were as follows: clearance = 0.035 L/h/kg, terminal exponential volume of distribution = 2.59 L/kg, terminal exponential half-life = 60.6 hours (i.v.), p.o. maximum blood concentration = 48.2 ng/mL, time of p.o. maximum blood concentration = 1.5 hours, and absolute bioavailability = 22.3%. The respective parameters in normal subjects were as follows: 0.040 L/h/kg, 1.91 L/kg, 34.2 hours (i.v.), 29.7 ng/mL, 1.6 hours, and 17.8%. Inasmuch as clearance and bioavailability were not substantially different from that in normal subjects, patients with mild hepatic impairment may initially be treated with conventional tacrolimus doses, with subsequent dosage adjustments based on response, toxicity, and therapeutic drug monitoring.

Topics: Body Weight; Cholelithiasis; Cross-Over Studies; Drug Administration Routes; Female; Humans; Immunosuppressive Agents; Liver; Liver Cirrhosis, Alcoholic; Male; Middle Aged; Tacrolimus; Time Factors

Hypertension frequently develops early after liver transplantation when cyclosporine-based immunosuppression is used. However, initial experience with tacrolimus has suggested that its use leads to a lower early incidence of hypertension. In this study, the blood pressure status of patients treated with cyclosporine (n = 131) and those treated with tacrolimus (n = 28) was compared 24 months after liver transplantation. At this time interval, the prevalence of hypertension in the cyclosporine and tacrolimus groups were 82% and 64%, respectively (P < .05). For those patients who were hypertensive by 24 months, onset was delayed in the tacrolimus group compared with the cyclosporine group: 40% versus 71% and 73% versus 93% at 1 and 12 months, respectively (P < .05). Within the cyclosporine group, patients with hypertension were heavier than those with normal blood pressure, 84.7 +/- 1.8 versus 73.4 +/- 4.0 kg, respectively (P < .05). Within the tacrolimus group, hypertensive patients had lower glomerular filtration rates and higher renal vascular resistances compared with normotensive patients, 74 +/- 12 versus 47 +/- 6 mL/min and 15,711 +/- 2,445 versus 28,830 +/- 4,310 dyne/s/cm5/m2, respectively (P < .05). There were no within-group differences for age, gender, pretransplant history of hypertension, family history of hypertension, graft function, or daily doses of prednisone, cyclosporine, or tacrolimus. These results indicate that, compared with cyclosporine, the onset of hypertension after liver transplantation is delayed and less prevalent with tacrolimus. Additionally, hypertension is associated with increased body weight in cyclosporine-treated patients and with more severe renal dysfunction in patients receiving tacrolimus. The relationships of these findings to the development of posttransplant hypertension requires further study.

Topics: Blood Pressure; Body Weight; Cyclosporine; Female; Follow-Up Studies; Glomerular Filtration Rate; Graft Rejection; Humans; Hypertension; Immunosuppressive Agents; Kidney; Liver Transplantation; Male; Middle Aged; Retrospective Studies; Tacrolimus; Vascular Resistance

Patient and primary graft survival for 2,090 patients who received primary liver transplants at the University of Pittsburgh from 1984 through 1990 are presented. Observed (actual) 3- and 12-month patient and primary graft survival rates were compared for 3 periods: 1) January 1984 to September 1987 (cyclosporine, OKT3, and Euro-Collins preservation period); 2) October 1987 to December 1988 (University of Wisconsin solution preservation period); and 3) January 1989 to December 1990 (FK506 period). Data for results according to age group, medical urgency, and primary diagnosis are provided. In addition, estimated survivor and cumulative hazard functions (life-table method) for patient and primary graft survival out to 60 months after transplantation are presented. Overall results have improved significantly in recent experience. Most notable are the improved results seen in liver transplantation for patients with biliary atresia (especially in infants), primary sclerosing cholangitis, fulminant hepatic failure, and chronic active hepatitis B. For all but a few conditions, most of the mortality after liver transplantation occurred in the first 3 months after surgery. Less than 2% of patients were lost in each 6-month interval beyond the first 6 months after transplantation. Outcome was related to patient condition at the time of surgery. Observed survival rates at 3 and 12 months for patients called in the hospital to receive a transplant were 88.6% and 86.5%, respectively, compared with 81.9% and 73.7% for patients in critical condition. The continuing shortage of organs for transplantation, which often forces patients to wait longer for an organ than they can afford to, continues to impose a significant penalty.

Topics: Adolescent; Age Factors; Body Weight; Child; Child, Preschool; Cyclosporine; Graft Survival; Hepatic Encephalopathy; Humans; Immunosuppression Therapy; Infant; Liver Function Tests; Liver Transplantation; Postoperative Complications; Prednisone; Reoperation; Survival Rate; Tacrolimus

The development of diabetes mellitus (DM) after living donor kidney transplantation (KT) is a risk factor for worsening transplant kidney function, cardiac disease, and cerebrovascular disease, which may affect prognosis after KT. At our institution, all patients' glucose tolerance is evaluated perioperatively by oral glucose tolerance tests (OGTTs) at pre-KT, and 3, 6, and 12 month (mo.) after KT. We analyzed the insulinogenic index (ISI) and homeostasis model assessment beta cell (HOMA-β) based on the immunoreactive insulin (IRI) levels to determine how glucose tolerance changed after KT in 214 patients who had not been diagnosed with DM before KT. In addition, we analyzed the body mass index (BMI) which may also influence glucose tolerance after KT. The concentration of tacrolimus (TAC) in blood was also measured as the area under the curve (AUC) to examine its effects at each sampling point. The preoperative-OGTTs showed that DM was newly diagnosed in 22 of 214 patients (10.3%) who had not been given a diagnosis of DM by the pre-KT fasting blood sugar (FBS) tests. The glucose tolerance was improved in 15 of 22 DM patients at 12 mo. after KT. ISI and IRI deteriorated only at 3 mo. after KT but improved over time. There was a trend of an inverse correlation between HOMA-β and TAC-AUC. We also found inverse correlations between IRI and an increase in BMI from 3 to 12 mo. after KT. Early corticosteroid withdrawal or the steroid minimization protocol with tacrolimus to maintain a low level of diabetogenic tacrolimus and BMI decrease after KT used by our hospital individualizes lifestyle interventions for each patient might contribute to an improvement in post-KT glucose tolerance.

Topics: Blood Glucose; Body Weight; Diabetes Mellitus, Type 2; East Asian People; Glucose; Humans; Insulin; Insulin Resistance; Kidney Transplantation; Steroids; Tacrolimus

The tacrolimus concentration within peripheral blood mononuclear cells may correlate better with clinical outcomes after transplantation compared to concentrations measured in whole blood. However, intracellular tacrolimus measurements are not easily implemented in clinical practice. The prediction of intracellular concentrations based on whole-blood concentrations would be a solution for this. Therefore, the aim of this study was to describe the relationship between intracellular and whole-blood tacrolimus concentrations in a population pharmacokinetic (popPK) model.. Pharmacokinetic analysis was performed using non-linear mixed effects modelling software (NONMEM). The final model was evaluated using goodness-of-fit plots, visual predictive checks, and a bootstrap analysis.. A total of 590 tacrolimus concentrations from 184 kidney transplant recipients were included in the study. All tacrolimus concentrations were measured in the first three months after transplantation. The intracellular tacrolimus concentrations (n  = 184) were best described with an effect compartment. The distribution into the effect compartment was described by the steady-state whole-blood to intracellular ratio (R. We were able to accurately describe intracellular tacrolimus concentrations using whole-blood concentrations, lean body weight, and haematocrit values in a popPK model. This model may be used in the future to more accurately predict clinical outcomes after transplantation and to identify patients at risk for under- and overexposure. Dutch National Trial Registry number NTR2226.

Topics: Area Under Curve; Bayes Theorem; Body Weight; Humans; Immunosuppressive Agents; Kidney Transplantation; Leukocytes, Mononuclear; Models, Biological; Tacrolimus

Tacrolimus dosing immediately posttransplant is based on body weight. Recent studies have highlighted that the dosing of tacrolimus purely based on weight may not be appropriate, particularly in individuals who are obese.. This study aimed to estimate the effect of body mass index (BMI) and the weight-based dosing on tacrolimus trough levels in recipients of renal transplants.. Patients in the higher BMI group (Group 3) had significantly higher baseline tacrolimus trough levels despite receiving a lower initiation dose per kilogram of body weight. After 1 and 6-months posttransplant, the higher BMI group were receiving a significantly lower tacrolimus dose relative to their body weight, with a significant negative correlation between body weight and tacrolimus/kg body weight. There was no adverse relationship evident between tacrolimus dosing or concentration and graft function.. Our study showed that standard dosing of tacrolimus based on body weight in individuals who were obese did not adversely affect their tacrolimus concentrations or transplant function.

Topics: Adult; Body Mass Index; Body Weight; Dose-Response Relationship, Drug; Female; Humans; Immunosuppressive Agents; Kidney Transplantation; Male; Middle Aged; Tacrolimus

Tacrolimus (TAC) pharmacokinetics is influenced by the donor CYP3A5 genotype and the age of pediatric liver recipients. However, an optimization of a genotype-based algorithm for determining TAC starting is needed to earlier achieve stable target levels. As the graft itself is responsible for its metabolism, the Graft-to-Recipient Weight Ratio (GRWR) might play a role in TAC dose requirements. A single-center study was carried out in a cohort of 49 pediatric recipients to analyse the impact of patient and graft characteristics on TAC pharmacokinetics during the first 15 post-transplant days. Children < 2 years received grafts with a significantly higher GRWR (4.2%) than children between 2-8 (2.6%) and over 8 (2.7%). TAC concentration/weight-adjusted dose ratio was significantly lower in recipients from CYP3A5*1/*3 donors or with extra-large (GRWR > 5%) or large (GRWR 3-5%) grafts. The donor CYP3A5 genotype and GRWR were the only significant predictors of the TAC weight adjusted doses. Patients with a GRWR > 4% had a higher risk of acute rejection, observed in 20/49 (41%) patients. In conclusion, TAC starting dose could be guided according to the donor CYP3A5 genotype and GRWR, allowing for a quicker achievement of target concentrations and eventually reducing the risk of rejection.

Topics: Adolescent; Age Factors; Body Weight; Child; Child, Preschool; Cohort Studies; Cytochrome P-450 CYP3A; Drug Monitoring; Female; Genotype; Graft Rejection; Humans; Immunosuppressive Agents; Infant; Liver; Liver Transplantation; Male; Organ Size; Postoperative Period; Tacrolimus; Tissue Donors; Transplants

Tacrolimus dosing is routinely tailored based on its trough level (C0) drawn by therapeutic drug monitoring in pediatric patients with primary nephrotic syndrome. However, this concentration is often inaccurate owing to inappropriate practice, such as deviation of sampling time (DST). The quantitative relationship between DST and C0 remains unclear.. Tacrolimus concentration at nominal sampling times (12 hours after last dose) and 32 deviation scenarios (12 ± 4 hours every 15 minutes) was predicted using a previously validated population pharmacokinetic model based on 162 scenarios of 100 primary nephrotic syndrome patients involved in the population pharmacokinetic model and derived virtual patients. Concentration error (CE) and relative CE (RCE) were evaluated, and the correlation between DST and RCE was evaluated by subgroup analysis using linear regression. Ultimately, the inappropriate dosing possibly misled by incorrect C0 was simulated in a real-patient cohort according to the target range (5-10 ng/mL).. Approximately 7% of RCE was caused at every 1-hour of DST. DST was the most major contributor of RCE (r = 0.773-0.804). Patients with early sampling, older age, high body weight, high dose, low aspartate transaminase level, high corticosteroid dose, and without combination of azole antifungal agents were revealed to have high RCE. Approximately 7%-36% and 9%-25% of inappropriate dose tailoring may be caused by early and delayed sampling, respectively. In addition, patients with early sampling or high-dose tacrolimus had a higher risk of inappropriate dosing than patients with delayed sampling [hazard ratio = 1.53, 95% confidence interval (CI): 1.03-2.27, P = 0.048], and low-dose tacrolimus (P < 0.0001).. A moderate bias of concentration and dose tailoring was revealed within 4 hours of DST. In addition, a high risk of bias was found in patients with early sampling and high-dose tacrolimus.

Topics: Adolescent; Adrenal Cortex Hormones; Age Factors; Antifungal Agents; Area Under Curve; Aspartate Aminotransferases; Body Weight; Child; Child, Preschool; Computer Simulation; Dose-Response Relationship, Drug; Drug Monitoring; Drug Therapy, Combination; Female; Humans; Immunosuppressive Agents; Infant; Male; Nephrotic Syndrome; Tacrolimus

Tacrolimus is one of the most widely used liver transplant medications. With the increasing number of obese patients requiring liver transplants, knowledge of the effect of body size affecting post-transplant outcomes, for example drug exposure is increasingly required.. (i) To investigate whether patient body size (i.e. total bodyweight) affects trough plasma concentrations of tacrolimus when a standard mg/kg dosing regimen is used; and (ii) to investigate whether obese patients have different numbers of plasma concentrations outside the therapeutic range compared to non-obese patients in the first months after liver transplant.. Using a transplant database, data tacrolimus concentrations were available for 69 patients. Tacrolimus was initially dosed at a standard 0.1 mg/kg/day after liver transplant, and adjusted to maintain a target trough concentration. Trough blood samples, phenotypic and outcome variables were analysed.. Trough concentrations were similar between obese and non-obese patients (P > 0.05) at each sampling day. At day 7 post-transplant, 85.7% and 79.5% of the observed plasma concentrations were outside the recommended therapeutic range for obese and non-obese patients respectively, at day 30, 52.9% and 57.4%, and at 6 months, 18.7% and 27.5%.. In the first week post-transplant, tacrolimus trough concentrations after standard mg/kg dosing post liver transplant appear to be corrected by total bodyweight. Obese patients have a similar number of trough plasma concentrations outside the therapeutic range compared to non-obese patients.

Topics: Adult; Aged; Body Weight; Female; Humans; Immunosuppressive Agents; Liver Transplantation; Male; Middle Aged; Obesity; Retrospective Studies; Tacrolimus

Administration of FK506, an FDA approved immunosuppressant, has been shown to enhance nerve regeneration following peripheral nerve injuries. However, the severe side effects of the systemically delivered FK506 has prevented clinicians from the routine use of the drug. In this study, we analyzed the effectiveness of our fibrin gel-based FK506 delivery system to promote axon regeneration in a rat peripheral nerve transection and immediate surgical repair model. In addition, biodistribution of FK506 from the local delivery system to the surrounding tissues was analyzed in vivo. Rats in the negative control groups either did not receive any delivery system treatment or received fibrin gel with empty microspheres. The experimental groups included rats treated with fibrin gel loaded with solubilized, particulate, and poly(lactic-co-glycolic) acid microspheres-encapsulated FK506. Rats in experimental groups receiving FK506 microspheres and the particulate FK506 regenerated the highest number of motor and sensory neurons. Histomorphometric analysis also demonstrated greater numbers of myelinated axons following particulate FK506 and FK506 microspheres treatment compared to the negative control groups. In biodistribution studies, FK506 was found at the nerve repair site, the sciatic nerve, and spinal cord, with little to no drug detection in other vital organs. Hence, the local application of FK506 via our delivery systems enhanced axon regeneration whilst avoiding the toxicity of systemic FK506. This local delivery strategy represents a new opportunity for clinicians to use for cases of peripheral nerve injuries. STATEMENT OF SIGNIFICANCE: This work for the first time investigated the influence of locally administered FK506 to the site of nerve injury and immediate repair directly on the number of motor and sensory neurons that regenerated their axons. Furthermore, using the immediate nerve repair model, we obtained valuable information about the biodistribution of FK506 within the nervous system following its release from the delivery system implanted at the site of nerve injury and repair. The strategy of local FK506 delivery holds a great promise in the clinical translation, as the localized delivery circumvents the main limitation of the systemic delivery of FK506, that of immunosuppression and toxicity.

Topics: Animals; Axons; Body Weight; Drug Delivery Systems; Female; Microspheres; Nerve Regeneration; Nerve Tissue; Peripheral Nerve Injuries; Rats, Sprague-Dawley; Tacrolimus; Tissue Distribution

Multiple clinical, demographic, and genetic factors affect the pharmacokinetics of tacrolimus in children, yet in daily practice, a uniform body-weight based starting dose is used. It can take weeks to reach the target tacrolimus pre-dose concentration.. The objectives of this study were to determine the pharmacokinetics of tacrolimus immediately after kidney transplantation and to find relevant parameters for dose individualization using a population pharmacokinetic analysis.. A total of 722 blood samples were collected from 46 children treated with tacrolimus over the first 6 weeks after renal transplantation. Non-linear mixed-effects modeling (NONMEM. The data were accurately described by a two-compartment model with allometric scaling for bodyweight. Mean tacrolimus apparent clearance was 50.5 L/h, with an inter-patient variability of 25%. Higher bodyweight, lower estimated glomerular filtration rate, and higher hematocrit levels resulted in lower total tacrolimus clearance. Cytochrome P450 3A5 expressers and recipients who received a kidney from a deceased donor had a significantly higher tacrolimus clearance. The model was successfully externally validated. In total, these covariates explained 41% of the variability in clearance. From the significant covariates, the cytochrome P450 3A5 genotype, bodyweight, and donor type were useful to adjust the starting dose to reach the target pre-dose concentration. Dosing guidelines range from 0.27 to 1.33 mg/kg/day.. During the first 6 weeks after transplantation, the tacrolimus weight-normalized starting dose should be higher in pediatric kidney transplant recipients with a lower bodyweight, those who express the cytochrome P450 3A5 genotype, and those who receive a kidney from a deceased donor.

Topics: Adolescent; Age Factors; Body Weight; Child; Child, Preschool; Computer Simulation; Cytochrome P-450 CYP3A; Drug Administration Schedule; Drug Dosage Calculations; Female; Genotype; Graft Rejection; Graft Survival; Humans; Immunosuppressive Agents; Kidney Transplantation; Male; Models, Biological; Nonlinear Dynamics; Pharmacogenomic Variants; Retrospective Studies; Tacrolimus; Tissue Donors; Treatment Outcome

Over the years, survival after liver transplantation has increased and metabolic complications are becoming more common, contributing to patients' morbidity and mortality. The objectives of this study were to describe a population of patients with hepatic transplantation and diabetes mellitus (DM), evaluate the frequency of metabolic complications, and assess the impact of a multidisciplinary team on DM management.. This was a retrospective study involving interview and medical record analysis of 46 consecutive patients followed at the diabetes mellitus and liver transplantation unit of a tertiary university hospital, all evaluated by a multidisciplinary team.. Of all patients, 76.1% were men, with a median age 60 years old (interquartile range: 56 to 65 years) and liver transplantation time of 5 years (interquartile range: 0.6-9 years). Hypertension, hypercholesterolemia, hypertriglyceridemia, alcoholism, and smoking were present in 47.8%, 34.8%, 23.9%, 34.8%, and 30.4% of the patients, respectively. The most frequent immunosuppressant in use was tacrolimus (71.1%). Regarding nutritional status, 37.9% of patients were classified as overweight according to body mass index, and 41.2% were considered overweight according to the triceps skin fold. The median glycosylated hemoglobin and weight before and after intervention of the multidisciplinary team in all 46 patients were, respectively, 7.6% (5.7% to 8.8%) versus 6.5% (5.7% to 7.7%); P = .022 and 70.5 kg (64.7 to 82.0 kg) versus 71.6 kg (65.0 to 85.0 kg); P = .18.. Hypertension and dyslipidemia were common in transplanted patients with DM. Intervention of the multidisciplinary team resulted in a significant improvement in glycosylated hemoglobin without significant weight gain.

Topics: Aged; Body Mass Index; Body Weight; Diabetes Mellitus; Female; Glycated Hemoglobin; Humans; Hypercholesterolemia; Hypertension; Hypertriglyceridemia; Immunosuppressive Agents; Liver Transplantation; Male; Middle Aged; Nutritional Status; Patient Care Team; Postoperative Complications; Postoperative Period; Retrospective Studies; Risk Factors; Tacrolimus

BACKGROUND We investigated whether a low fixed Tac starting dose regimen could lead to a better achievement of Tac target concentrations, as well as an effective immunosuppressive treatment, in Chinese kidney transplant recipients (KTRs). MATERIAL AND METHODS We collected whole-blood and serum samples from 189 KTRs and the Tac starting dose was 2, 2.5, or 3 mg/day. Information on Tac C0, dose, body weight, body mass index (BMI), Scr, eGFR, and CYP3A5 genotypes were collected from a routine therapeutic drug monitoring database. The correlation between Tac C0 and body weight (or BMI) was investigated by calculating the goodness of fit. Multivariable logistic regression was performed to estimate the independent associated factors. RESULTS The patients with 3 mg per day of Tac had higher C0 at day 7 compared to those with 2 or 2.5 mg. For patients receiving the same Tac starting dose, no significant difference was found in Tac C0 at day 7 among different body weight or BMI groups. There was no significant difference in Scr or eGFR at 1 year after transplant, nor was there a significant difference in the rates of DGF or AR at post-transplant day 30 among different Tac starting dose groups or among the 3 Tac C0 range groups. CYP3A5 genotype and Tac initial dose were independently associated with Tac C0. CONCLUSIONS CYP3A5 genotype and Tac initial dose were independently associated with Tac C0 in renal transplant recipients. Our results suggest that a low Tac target C0 range (5-8 ng/ml) with a low fixed starting dose (3 mg/day) would be safe and effective among Chinese KTRs.

Topics: Adult; Asian People; Body Weight; China; Cytochrome P-450 CYP3A; Dose-Response Relationship, Drug; Drug Monitoring; Female; Graft Rejection; Humans; Immunosuppressive Agents; Kidney Transplantation; Logistic Models; Male; Polymorphism, Single Nucleotide; Retrospective Studies; Tacrolimus; Transplant Recipients; Young Adult

Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disease, and excessive T lymphocyte activation plays a critical role in the development of inflammation. CD147 is an antigen related to T cell activation, CD147 blockade exerts beneficial effects on RA. FK506, also known as tacrolimus, exerts strong immunosuppressive effects by inhibiting T cell activation. In this study, RL73 (an anti-mouse CD147 functional-grade purified antibody) and FK506 were co-administered to mice with collagen-induced arthritis (CIA). As expected, the combination of these two drugs produced superior therapeutic effects than either drug alone and enabled the administration of each drug at a lower dose. Moreover, joint damage and destruction were significantly improved in mice injected with both FK506 and RL73 compared with mice injected with either agent alone. These effects might have been observed because the proportions of CD4 + T and CD8 + T cells in the mouse spleen of the combination regimen were clearly decreased compared with each monotherapy. In addition, the proportions of Th2 subsets in the mouse spleen and peripheral blood were clearly increased, and the serum levels of the cytokines interleukin 4 (IL-4) and IL-10 were markedly increased in mice treated with the combination therapy compared with the other groups of mice. The splenic total number of T lymphocytes also showed that the inhibition of T lymphocytes was the most obvious in the combined treatment group. Based on the results from the present study, combining FK506 and the anti-CD147 mAb might be a new practical therapeutic option for the treatment of RA.

Topics: Animals; Antibodies, Monoclonal; Arthritis, Experimental; Basigin; Body Weight; Chickens; Disease Models, Animal; Drug Therapy, Combination; Edema; Female; Inflammation; Interleukin-10; Interleukin-4; Mice; Spleen; Tacrolimus; Th2 Cells

The aim of the present study was to investigate the protective effect of tacrolimus on early podocyte damage in rats with diabetic nephropathy (DN). A total of 38 normal male Sprague‑Dawley rats were randomly divided into four groups: Normal control group (group N; n=8), DN group (n=10), tacrolimus (FK506) treatment group (group F; n=10), benazepril (Lotensin) treatment group (group L; n=10). The rats in groups DN, F and L were administered with streptozotocin (STZ; 60 mg/kg) by intraperitoneal injection to establish the diabetic rat model. After 4 weeks, the diabetic rat model was established, and rats in the different groups were administered intragrastically with the respective drugs. Blood glucose (BS), body weight (BW) and 24‑h urine protein were detected every 4 weeks, serum creatinine (SCr), blood urea nitrogen (BUN) and kidney weight/body weight (KW/BW) were measured at the end of the 8 weeks of drug treatment. Renal pathological changes were observed under a light microscope and electron microscope. Expression of nephrin, which is a podocyte‑specific marker, was detected using western blot analysis. The results showed that the levels of SCr, BUN, KW/BW and 24‑h urine protein in groups D, F and L were significantly higher, compared with those in group N (P<0.05). No significant differences were found between groups F and L for the above indicators, with the exception of BS. However, all indices were significantly lower, compared with those in group DN (P<0.05). Renal pathological expression was normal in group N under light microscopy. There were significant increases in the glomerular volume, proliferative mesangial cells, width of the mesangial area and thickness of the basement membrane in group DN, however, all the above pathological characteristics were reduced in groups F and L, compared with group DN (P<0.05). No significant difference was found between groups F and L. A widened glomerular basement membrane, and disorder, widening and fusion of podocyte processes were observed under the electron microscope in group DN, however, these were reduced in groups F and L, compared with group DN (P<0.05). The results of the western blot analysis showed that the expression of nephrin decreased by 60.1% in group DN, compared with group N, and significant recovery in the expression of nephrin was observed in groups F and L (P<0.05). Tacrolimus reduced urinary protein and slowed the progression of DN, partially by recovering the protein expression of n

Topics: Animals; Blood Glucose; Blood Urea Nitrogen; Body Weight; Creatinine; Diabetes Mellitus, Experimental; Kidney; Male; Membrane Proteins; Microscopy, Electron, Transmission; Podocytes; Protective Agents; Rats; Rats, Sprague-Dawley; Streptozocin; Tacrolimus

Topics: Body Weight; Cytochrome P-450 CYP3A; Genotype; Humans; Hydroxycholesterols; Immunosuppressive Agents; Kidney Transplantation; Tacrolimus

The cause of post-transplant CNI-NCs is multifactorial and not ascribed solely to CNI toxicity. A total of 90 children (aged <20 years) who underwent LDLT were evaluated to investigate the predictive factors associated with CNI-NCs. Twelve patients (13.3%) developed CNI-NCs after LDLT (age range, 2-15 years). The symptoms of CNI-NCs were seizures, VD, and stupor. The median onset of CNI-NCs was 10 days (range, 5-30 days) post-transplant. In the univariate analysis, higher recipient age at LDLT, donor age and recipient's BW, lower actual GV/SLV and TAC dosage/BW, and higher mean T-Bil and sodium level for 7 days after transplantation were independently significantly associated with TAC-NCs. Multivariate analysis showed that the T-Bil level in the first week after LDLT was the only significant independent predictive factor for TAC-NCs (HR, 1.588; 95% CI, 1.042-2.358; P=.031). In conclusion, CNI-NCs occurred most frequently in children over 5 years and were associated with hyperbilirubinemia for 7 days post-transplant, regardless of TAC levels. The transplant team should refer to a neurologist to define the diagnosis and to collaborate to resolve the neurological problems.

Topics: Adolescent; Age of Onset; Bilirubin; Body Weight; Calcineurin Inhibitors; Child; Child, Preschool; Female; Humans; Hyperbilirubinemia; Immunosuppressive Agents; Infant; Liver Failure; Liver Transplantation; Living Donors; Male; Multivariate Analysis; Nervous System Diseases; Postoperative Complications; Proportional Hazards Models; Retrospective Studies; Risk Factors; Stupor; Tacrolimus

Topics: Body Weight; Cytochrome P-450 CYP3A; Genotype; Humans; Hydroxycholesterols; Immunosuppressive Agents; Kidney Transplantation; Tacrolimus

The aim of the present study was to investigate the influence of the cytochrome P450 (CYP) 3A4/5 genotype in paediatric liver transplant recipients and donors, and the contribution of age and gender to tacrolimus disposition on the first day after transplantation.. Donor CYP3A5 genotype, recipient age and, to a lesser extent, donor gender appear to be associated with tacrolimus disposition on day 1 after transplant. This suggests that increasing the starting tacrolimus doses in paediatric patients under 6 years of age who receive a graft from a male extensive metabolizer may enhance the possibility of their tacrolimus levels reaching the therapeutic range sooner.

Topics: Adolescent; Aging; Body Weight; Child; Child, Preschool; Cytochrome P-450 CYP3A; Female; Genetic Variation; Genotype; Humans; Immunosuppressive Agents; Infant; Linear Models; Liver Transplantation; Male; Sex Characteristics; Tacrolimus; Tissue Donors

Topics: Body Weight; Cytochrome P-450 CYP3A; Genotype; Humans; Hydroxycholesterols; Immunosuppressive Agents; Kidney Transplantation; Tacrolimus

The aim of this study was to develop a population pharmacokinetic model of tacrolimus in paediatric patients at least 1 year after renal transplantation and simulate individualised dosage regimens.. We included 54 children with median age of 11.1 years (range 3.8-18.4 years) with 120 pharmacokinetic profiles performed over 2 to 4 h. The pharmacokinetic analysis was performed using the non-linear mixed-effects modelling software (NONMEM(®)). The impact of covariates including concomitant medications, age, the cytochrome P450 (CYP) CYP3A5*3 gene and the adenosine triphosphate binding cassette protein B1 (ABCB1) 3435 C→T gene polymorphism on tacrolimus pharmacokinetics was analysed. The final model was externally validated on an independent dataset and dosing regimens were simulated.. A two-compartment model adequately described tacrolimus pharmacokinetics. Apparent oral clearance (CL/F) was associated with weight (allometric scaling) but not age. Children with lower weight and CYP3A5 expressers required higher weight-normalised tacrolimus doses. CL/F was inversely associated with haematocrit (P < 0.05) and γ-glutamyl transpeptidase (γGT) (P < 0.001) and was increased by 45 % in carriers of the CYP3A5*1 allele (P < 0.001). CL/F was not associated with concomitant medications. Dose simulations show that a daily tacrolimus dose of 0.2 mg/kg generates a pre-dose concentration (C 0) ranging from 5 to 10 µg/L depending on the weight and CYP3A5 polymorphism. The median area under the plasma concentration-time curve (AUC) corresponding with a tacrolimus C 0 of 4-8 µg/L was 97 h·µg/L (interquartile range 80-120).. In patients beyond the first year after transplantation, there is a cumulative effect of CYP3A5*1 polymorphism and weight on the tacrolimus C 0. Children with lower weight and carriers of the CYP3A5*1 allele have higher weight-normalised tacrolimus dose requirements.

Topics: Adolescent; Area Under Curve; ATP Binding Cassette Transporter, Subfamily B, Member 1; Body Weight; Child; Child, Preschool; Cohort Studies; Cytochrome P-450 CYP3A; Female; Genotype; Humans; Immunosuppressive Agents; Kidney Transplantation; Male; Metabolic Clearance Rate; Models, Biological; Netherlands; Polymorphism, Single Nucleotide; Retrospective Studies; Tacrolimus; Transplant Recipients

We report a 16-yr-old female who developed AN within a month after renal transplantation and its resolution after switching from tacrolimus to cyclosporine. Her initial maintenance immunosuppressive regimen after renal transplantation consisted of tacrolimus, mycophenolate, and steroid. She had 7 kg weight loss within the first month of transplant with subsequent 10, 12, 17, and 19 kg loss after three, five, seven, and nine months of transplant, respectively. Besides weight loss and disturbances in body image, the patient developed alopecia, bradycardia, and persistent secondary amenorrhea. Upon switching to cyclosporine from tacrolimus nine months after transplant, she started regaining weight with 5 kg gain within two months and 10 kg after four months. She restarted her menstrual cycle, alopecia and bradycardia resolved, and her body image disturbance improved. Here, we describe a very unusual neuropsychiatric side effect of tacrolimus and its resolution with another calcineurin inhibitor, cyclosporine, in an adolescent renal transplant recipient.

Topics: Adolescent; Anorexia Nervosa; Body Weight; Cyclosporine; Female; Graft Survival; Humans; Immunosuppressive Agents; Kidney Failure, Chronic; Kidney Transplantation; Tacrolimus; Transplant Recipients; Treatment Outcome

The use of the immunosuppressive drug tacrolimus (TAC) is related to new onset diabetes after transplantation. Herein, we examined the effect of intraperitoneal administered TAC on intestinal glucose absorption in mice.. Animals received low, medium, or high dose TAC (0.5, 1, or 5 mg/kg/d, respectively), or 0.9% saline solution (control) for 14 days. Oral glucose tolerance test (OGTT), insulin concentration test, and serum TAC concentration measurements was performed after 14 days of TAC exposure. Plasma insulin was assessed and electrogenic glucose absorption were measured by the sodium-dependent increase of the short-circuit current. Expression levels of the glucose transporters sodium glucose co-transporter (SGLT) 1, glucose transporter (GLUT) 2, and GLUT5 were also determined.. Oral glucose absorption assessed by OGTT was significantly enhanced in the low, medium, and high groups. Serum insulin was elevated in the medium and high group compared with the control. Moreover, glucose-induced Isc was significantly higher in TAC administrated groups, which indicates that SGLT1 activity increased. Transcription levels and protein abundance of SGLT1 in the experimental groups also increased compared with the control.. TAC induced insulin resistance and strengthened intestinal glucose absorption by increasing the activity and expression of the glucose transporter, SGLT1.

Topics: Animals; Biological Transport; Blood Glucose; Body Weight; Feeding Behavior; Glucose; Glucose Tolerance Test; Glucose Transport Proteins, Facilitative; Insulin; Insulin Resistance; Intestinal Absorption; Jejunum; Male; Mice, Inbred C57BL; Tacrolimus; Transcription, Genetic

Tacrolimus (TAC) pharmacokinetics (PKs) show considerable unexplained variability, particularly in the early period after transplantation. Therefore, TAC is a good candidate for therapeutic drug monitoring. The main objective of the present work was to propose a robust PK model for TAC in the early period after transplantation, with the final goal to provide practitioners with a tool for dose individualization in pediatric patients.. TAC concentration data were obtained from 82 pediatric liver allograft recipients during the first 2 weeks after transplantation. Previously published models, and a model recently developed by our group for pediatrics early after pediatric liver transplantation, were fitted to the data and their predictive performance compared with the performances of a model developed using the data from 82 pediatric patients.. During the data-driven analysis, the PKs of TAC were best described by a 1-compartment model with time-varying first order elimination. Apparent volume of distribution and blood clearance estimates were 283 L and 10 L/h, respectively. The absorption was also considered to be a first order process, with a first order rate fixed to 4.45 hours. Parameters were estimated with good precision and accuracy. Although hematocrit levels, time after transplantation, liver weight, and body weight influenced the clearance, body weight was the only covariate retained on volume of central and peripheral compartments. Two of the 5 previous models showed acceptable predictive performances using the observed data.. Time after transplantation, body weight, and hematocrit levels were shown to influence TAC PK in the early pediatric post-liver transplantation period and should be considered, besides therapeutic drug monitoring, by clinicians for the TAC posology prescription and adaptation.

Topics: Adolescent; Body Weight; Child; Child, Preschool; Dose-Response Relationship, Drug; Drug Monitoring; Female; Hematocrit; Humans; Immunosuppressive Agents; Infant; Liver Transplantation; Male; Models, Biological; Retrospective Studies; Tacrolimus; Time Factors; Tissue Distribution

Tacrolimus, an immunosuppressant drug, presents a narrow therapeutic window and a large pharmacokinetic variability with poor correlation between drug dosing regimen and blood concentration. The objective was to identify predictive factors influencing tacrolimus trough concentrations (C0) using a bottom-up approach. A physiologically based pharmacokinetic (PBPK) model of tacrolimus was proposed, taking into account the body weight, the proportion of fat (P(fat)), hematocrit, lipid fraction of organs, typical intrinsic clearance (CLi(typ)), CYP3A5 genotype of liver donor, plasma unbound fraction of tacrolimus (fu(p)), and concomitant drugs (CYP3A4 inhibitors). For the evaluation of the PBPK model, mean C0 and concentrations 2 h after oral dose of tacrolimus were compared with those from 66 liver transplant recipients included in a multicentric pharmacokinetic study and were found very close. Tacrolimus concentration profiles were simulated in a virtual population defined by a set of covariate values similar to those from the real population. The sensitivity of tacrolimus C0 with respect to each covariate has been tested to identify the most influential ones. With the range of covariate values tested, the impact of each covariate on tacrolimus C0 may be ranked as follows: fu(p), CLi(typ), bioavailability, body weight, hematocrit, CYP3A5 polymorphism, P(fat), and CYP3A4 inhibitory drug-drug interactions. Values for initial dosing regimen of tacrolimus in order to reach a C0 of 10 ng/ml at day 5 (assuming a constant dosing schedule) as a function of CYP3A5 donor genotype and patient's hematocrit and body weight are proposed.

Topics: Adult; Aged; Body Weight; Cytochrome P-450 CYP3A; Female; Genotype; Humans; Immunosuppressive Agents; Intestinal Absorption; Liver Transplantation; Male; Middle Aged; Pharmacogenetics; Prospective Studies; Tacrolimus

To investigate the diabetogenic effects of the immunosuppressive agent tacrolimus, the reversibility of these effects upon treatment discontinuation, and the underlying mechanisms in a rat model.. 60 healthy male rats were randomly divided into three groups for intragastric administration of tacrolimus either at 4 mg/kg/d or 2 mg/kg/d or an equal volume of normal saline (control). The treatment was administered for 5 months, followed by a 5-month period of no intervention. Fasting plasma glucose and insulin levels were used to calculate the homeostasis model assessment of ß-cell function (HOMA-ß) and insulin sensitivity index (ISI).. Tacrolimus treatment significantly increased blood glucose concentrations (p < 0.05) and lowered HOMA-ß and ISI (p < 0.01) in a time- and dose-dependent manner. Five months after tacrolimus treatment, significant islet cell injury was observed. However, 5 months after tacrolimus discontinuation, blood glucose concentrations significantly declined, HOMA-β and ISI levels significantly increased, and islet cell morphology noticeably improved.. In conclusion, tacrolimus treatment of healthy rats increased blood glucose concentrations in a time- and concentration-dependent manner. Development of tacrolimus-induced diabetes and reversibility after tacrolimus discontinuation may involve factors of and interactions between the insulin secretion pathway, local and/or systemic insulin resistance, and islet cell damage.

Topics: Animals; Blood Glucose; Body Weight; Immunosuppressive Agents; Insulin; Insulin Resistance; Insulin Secretion; Islets of Langerhans; Male; Rats; Rats, Sprague-Dawley; Tacrolimus

Topics: Adolescent; Age Factors; Body Weight; Child; Child, Preschool; Cyclosporine; Dose-Response Relationship, Drug; Female; Graft Rejection; Heart Transplantation; Humans; Immunosuppressive Agents; Infant; Male; Mathematical Computing; Retrospective Studies; Tacrolimus; Time Factors

Tacrolimus is widely used in the prophylaxis of solid-organ transplant rejection. Several studies have reported that tacrolimus has variable and poor bioavailability after oral administration, apart from adverse effects such as gastrointestinal disorders, hyperglycemia, nephro- and neurotoxicity. The aim of this work was to encapsulate tacrolimus (TAC) in lipid-core nanocapsules (LNC) as an oral strategy to deliver the drug. To validate our hypothesis, the pharmacodynamic effect of TAC-LNC was determined after oral and intraperitoneal (i.p.) administrations to mice. TAC-LNC had z-average diameter of 210 nm (unimodal), and 99.5% of encapsulation efficiency. In vitro sustained release was determined for TAC-LNC fitting an anomalous transport mechanism (n = 0.8). TAC-LNC demonstrated higher immunosuppressive activity after oral and i.p. administrations, when compared to the drug solution. TAC-LNC administered at 6.0 mg kg(-1) day(-1) showed equivalent percent reduction in lymphocyte when both routes of administration were used. After oral administration, drug nanoencapsulation allows reducing the dose by at least 40%. Furthermore, the nanoencapsulation of TAC in lipid-core nanocapsules showed pharmacodynamic effect similar for the oral and the i.p. routes. In conclusion, the lipid-core nanocapsules were able to improve the TAC deliver across the oral absorption barrier.

Topics: Administration, Oral; Animals; Body Weight; Immunosuppressive Agents; Infusions, Parenteral; Lipids; Lymphocytes; Male; Mice; Nanocapsules; Tacrolimus

Topics: Adolescent; Antibodies, Monoclonal; Basiliximab; Body Weight; Child; Child, Preschool; Female; Humans; Immunosuppressive Agents; Kidney Failure, Chronic; Kidney Transplantation; Male; Methylprednisolone; Mycophenolic Acid; Recombinant Fusion Proteins; Retrospective Studies; Tacrolimus; Treatment Outcome

As a traditional immunosuppressive drug, tacrolimus showed the potency in treating ulcerative colitis. In this study, a novel drug delivery vehicle achieved by self-assembly was applied to tacrolimus. During the preparation, amphiphilic copolymer MPEG-PCL was chosen to form the unique core-shell structure, and tacrolimus was loaded into the hydrophobic core due to its great hydrophobicity. After several relevant tests, MPEG-PCL (2000-2000) was selected to be the most suitable and safest copolymer for drug carrier. For the tacrolimus loaded MPEG-PCL (2000-2000) micelles, the mean particle size and drug entrapment efficiency were ca. 25 +/- 5 nm and 98.47 +/- 0.43% respectively. The micelles could be stored for quite a long time even at room temperature after freeze-drying, and the freeze-drying process didn't affect the monodispersity of micelles. Transmission electron microscope (TEM) image emerged the spherical shape of micelles. Both Differential Scanning Calorimetric (DSC) and X-ray Diffractometer (XRD) assays demonstrated that tacrolimus was relatively completely incorporated into the core-shell structure. In vitro release profiles showed the apparent sustained release behavior compared with tacrolimus solution. Above all, animal treatment showed the most satisfactory therapeutic effect of tacrolimus loaded micelles, which means the micelles possess the ability to treat ulcerative colitis induced by dextran sulfate sodium (DSS) in mice. Therefore, micelles of MPEG-PCL could be a very promising novel vehicle for tacrolimus.

Topics: Animals; Body Weight; Calorimetry, Differential Scanning; Colon; Drug Delivery Systems; Hemolysis; Male; Mice; Mice, Inbred BALB C; Micelles; Microscopy, Electron, Transmission; Particle Size; Polyesters; Polyethylene Glycols; Rabbits; Tacrolimus; Temperature; X-Ray Diffraction

Use of immunosuppressant drugs has been associated with complications in wound healing. The calcineurin inhibitor tacrolimus is thought to have a relatively low complication rate, but preclinical research has yielded contradictory data, prompting the current comprehensive study.. Three groups of 33 male Wistar rats received a daily subcutaneous dose of 0,5, 2 or 5 mg/kg tacrolimus. A control group received saline. On day 0 a resection of 1 cm ileum and 1 cm colon was performed, and end-to-end anastomoses were constructed. Ten rats of each group were killed on day 3 and day 5 and the remaining animals on day 7. Both anastomoses and the wound in the abdominal wall were analyzed. Wound strength was the primary outcome parameter.. Mean strength of the abdominal wall increased significantly over time in all groups (p<0.0001). Both the breaking strength and the bursting pressure of the ileum and colon anastomoses followed the same pattern. No differences were observed between control and experimental groups. In addition, no consistent differences were found between groups regarding wound hydroxyproline content and the activities of matrix metalloproteinase-2 and -9.. Tacrolimus does not affect early wound healing.

Topics: Abdominal Wall; Abdominal Wound Closure Techniques; Anastomosis, Surgical; Animals; Body Weight; Dose-Response Relationship, Drug; Histological Techniques; Immunosuppressive Agents; Injections, Subcutaneous; Intestine, Large; Male; Rats; Rats, Wistar; Tacrolimus; Wound Healing

Over the past several years, tacrolimus has attracted attention as a new therapeutic drug for myasthenia gravis (MG), but few reports have considered its use for MG in pediatric patients, and most of these have focused on severe systemic MG. In this case report, we used tacrolimus to successfully treat a 13-year-old boy with ocular MG who had suffered from severe steroid complications, including a failure of thrive and osteoporosis. He first showed symptoms of ocular MG at age 2 years 3 months. At age 13 years, he was receiving PSL (3.75 mg/day), but the symptoms of ocular MG recurred. We increased the dosage of oral PSL up to 30 mg/day, and three courses of mPSL pulse therapy were applied, but these therapies had only limited effect, and his symptoms worsened. Tacrolimus was started at 0.4 mg/day (0.011 mg/kg/day), and every 2 weeks the dose was gradually increased by 0.2 mg/day. His symptoms of MG began to improve 3 weeks after the initial administration of tacrolimus. Approximately 3 months after the start of tacrolimus administration, PSL was discontinued. Currently, at 1 year and 4 months after the start of tacrolimus administration, while slight ptosis is observed in the evening, it does not influence his daily life, and his condition remains comparable to that when he stopped taking PSL. No adverse effects of tacrolimus have been recognized. In pediatric patients with steroid-dependent ocular MG without thymectomy, tacrolimus may be a safe and effective alternative to steroid and thymectomy.

Topics: Adolescent; Body Weight; Developmental Disabilities; Follow-Up Studies; Humans; Immunosuppressive Agents; Male; Myasthenia Gravis; Tacrolimus

Excess fluid distribution is a common disorder in peritoneal dialysis (PD) patients. Tacrolimus malabsorption may also occur in PD patients, and may lead to acute allograft rejection after transplantation. The purpose of this study was to evaluate the relationship between tacrolimus pharmacokinetics and excess fluid distribution according to pre-transplant dialysis modality.. We retrospectively analyzed 41 adult living-donor kidney transplantations, including nine PD patients and 32 hemodialysis (HD) patients. We examined tacrolimus pharmacokinetics in the peri-operative period and determined the association between the tacrolimus absorption rate and body weight reduction. The absorption efficacy of tacrolimus was evaluated as the dose-normalized tacrolimus absorption rate. Tacrolimus concentrations in PD effluent were measured by high-performance liquid chromatography.. The tacrolimus absorption rate on the day before kidney transplantation tended to be lower in PD patients than in HD patients; however, the rate improved after kidney transplantation and was similar in both groups of patients. The peak tacrolimus concentration time was later in PD patients than in HD patients. The body weight reduction after kidney transplantation was greater in PD patients than in HD patients, and was significantly associated with the change in tacrolimus absorption rate (p=0.04, r=0.32). Only 0.002% of the oral tacrolimus dose was removed by PD itself.. Excess fluid distribution in PD patients appears to contribute to tacrolimus malabsorption rather than PD itself. We should consider the risk of tacrolimus malabsorption in patients with possible excess fluid distribution, particularly in PD patients.

Topics: Administration, Oral; Adult; Body Weight; Drug Dosage Calculations; Drug Monitoring; Female; Graft Survival; Humans; Immunosuppressive Agents; Intestinal Absorption; Kidney Transplantation; Living Donors; Male; Middle Aged; Peritoneal Dialysis; Renal Dialysis; Retrospective Studies; Tacrolimus; Treatment Outcome; Water-Electrolyte Imbalance

Tacrolimus, an immunosuppressive drug widely prescribed in kidney transplantation, requires therapeutic drug monitoring due to its marked interindividual pharmacokinetic variability and narrow therapeutic index. Previous studies have established that CYP3A5 rs776746 is associated with tacrolimus clearance, blood concentration, and dose requirement. The importance of other drug absorption, distribution, metabolism, and elimination (ADME) gene variants has not been well characterized.. We used novel DNA biobank and electronic medical record resources to identify ADME variants associated with tacrolimus dose requirement. Broad ADME genotyping was performed on 446 kidney transplant recipients, who had been dosed to a steady state with tacrolimus. The cohort was obtained from Vanderbilt's DNA biobank, BioVU, which contains linked deidentified electronic medical record data. Genotyping included Affymetrix drug-metabolizing enzymes and transporters Plus (1936 polymorphisms), custom Sequenom Massarray iPLEX Gold assay (95 polymorphisms), and ancestry-informative markers. The primary outcome was tacrolimus dose requirement defined as blood concentration to dose ratio.. In analyses, which adjusted for race and other clinical factors, we replicated the association of tacrolimus blood concentration to dose ratio with CYP3A5 rs776746 (P=7.15×10), and identified associations with nine variants in linkage disequilibrium with rs776746, including eight CYP3A4 variants. No NR1I2 variants were significantly associated. Age, weight, and hemoglobin were also significantly associated with the outcome. In final models, rs776746 explained 39% of variability in dose requirement and 46% was explained by the model containing clinical covariates.. This study highlights the utility of DNA biobanks and electronic medical records for tacrolimus pharmacogenomic research.

Topics: Adult; Age Factors; ATP Binding Cassette Transporter, Subfamily B; ATP Binding Cassette Transporter, Subfamily B, Member 1; Body Weight; Cytochrome P-450 CYP3A; Databases, Nucleic Acid; Dose-Response Relationship, Drug; Drug Monitoring; Electronic Health Records; Female; Genetic Association Studies; Genotype; Hemoglobins; Humans; Immunosuppressive Agents; Kidney Transplantation; Linkage Disequilibrium; Male; Middle Aged; Polymorphism, Single Nucleotide; Pregnane X Receptor; Receptors, Steroid; Tacrolimus

  TAC, MMF and MP are used in pediatric kidney tx. The cytochrome P450 (CYP)3A5 enzyme appears to play a role in TAC metabolism. The aims of this study were to investigate CYP3A5 polymorphism's effect on TAC dosing and the age dependency of TAC dosing by testing blood concentrations, and the interaction between steroids and TAC during the first year after tx. Genomic DNA was extracted and amplified with specific primers. CYP3A5 alleles were confirmed by direct sequencing of PCR products on an automated AB13100 capillary sequencer. We studied 48 renal transplant patients (age at tx 12±0.5yr, 22 boys) receiving TAC, MMF, MP. Of these, 79% were CYP3A5*3/*3 (non-expressers homozygotes) and 21% were CYP3A5*1/*3 (expressers). TAC trough levels were 7.1±0.4ng/mL in CYP3A5*3/*3 patients and 6.5±0.7ng/mL in CYP3A5*1/*3 group (p=0.03). CYP3A5*1/*3 patients had lower levels of dose-adjusted TAC (36.7±5.8ng/mL/mg/kg/day) to achieve target blood concentration and required higher daily dose per weight (0.21±0.03mg/kg/day) than CYP3A5*3/*3 patients, 72.4±8.0ng/mL/mg/kg/day and 0.13±0.01mg/kg/day (p<0.001). Prepubertal patients with different CYP3A5 polymorphisms required significant higher TAC doses and achieved lower dose-normalized concentration compared with pubertal patients. Both TAC dose and adjusted-dose correlated with daily MP dose in CYP3A5*1*3 (r: 0.4, p<0.03 and r: 0.4, p<0.03) and in CYP3A5*3*3 (r: 0.6, p<0.01 and r: 0.47, p<0.001) patients. CYP3A5 polymorphism performed before tx could contribute to a better individualization of TAC therapy. The higher TAC dose in prepubertal patients and the pharmacological interactions between MP and TAC may not be fully explained by different CYP3A5 polymorphisms.

Topics: Adolescent; Age Factors; Body Weight; Child; Cytochrome P-450 CYP3A; DNA Primers; Female; Homozygote; Humans; Kidney Transplantation; Male; Methylprednisolone; Mycophenolic Acid; Polymorphism, Genetic; Steroids; Tacrolimus; Treatment Outcome

This work seeks to evaluate the association between the C/D ratios (plasma concentration of tacrolimus divided by daily dose of tacrolimus per body weight) of tacrolimus and the haplotypes of MDR1 gene combined by C1236T (rs1128503), G2677A/T (rs2032582) and C3435T (rs1045642), and to further determine the functional significance of haplotypes in the clinical pharmacokinetics of oral tacrolimus in Han Chinese liver transplant recipients.. The tacrolimus blood concentrations were continuously recorded for one month after initial administration, and the peripheral blood DNA from a total of 62 liver transplant recipients was extracted. Genotyping of C1236T, G2677A/T and C3435T was performed, and SNP frequency, Hardy-Weinberg equilibrium, linkage disequilibrium, haplotypes analysis and multiple testing were achieved by software PLINK. C/D ratios of different SNP groups or haplotype groups were compared, with a p value<0.05 considered statistically significant. Linkage studies revealed that C1236T, G2677A/T and C3435T are genetically associated with each other. Patients carrying T-T haplotype combined by C1236T and G2677A/T, and an additional T/T homozygote at either position would require higher dose of tacrolimus. Tacrolimus C/D ratios of liver transplant recipients varied significantly among different haplotype groups of MDR1 gene.. Our studies suggest that the genetic polymorphism could be used as a valuable molecular marker for the prediction of tacrolimus C/D ratios of liver transplant recipients.

Topics: Adult; Asian People; ATP Binding Cassette Transporter, Subfamily B, Member 1; Body Weight; Dose-Response Relationship, Drug; Ethnicity; Female; Haplotypes; Humans; Immunosuppressive Agents; Liver Transplantation; Male; Middle Aged; Polymorphism, Single Nucleotide; Tacrolimus; Young Adult

Ethnic differences in drug pharmacokinetics are well recognized including that for tacrolimus (TAC) in adult subjects. However, similar knowledge among pediatric populations is missing. Our limited retrospective study compares steady-state pharmacokinetics of TAC in Hispanic versus non-Hispanic children. Serial blood samples were collected and whole blood concentrations of TAC were measured using radioimmunoassay. Compared with non-Hispanic children, Hispanic children had lower measures of drug exposure (maximum drug concentration [Cmax] and area under the drug concentration-time curve [AUC0-∞]), higher volume of distribution, and faster clearance. Interestingly, only in Hispanic children, significant correlations were found between body weight and clearance, age and volume of distribution, and Schwartz estimated glomerular filtration rate and half-life. In conclusion, our study suggests that ethnic differences exist between Hispanic and non-Hispanic children in TAC PK, and based on our preliminary findings, either a higher or more frequent TAC dosing may be required for effective immunosuppression therapy in Hispanic children.

Topics: Adolescent; Age Factors; Area Under Curve; Body Weight; Child; Child, Preschool; Drug Dosage Calculations; Drug Monitoring; Female; Glomerular Filtration Rate; Hispanic or Latino; Humans; Immunosuppressive Agents; Infant; Kidney Transplantation; Male; Metabolic Clearance Rate; Oregon; Radioimmunoassay; Retrospective Studies; Tacrolimus

Intestinal transplantation (ITx) is a life-saving procedure for patients with intestinal failure. The poorer outcome of ITx than of other organ transplantation, however, warrants more clinical and basic research on ITx. Herein, we developed a modified Paul-Mikulicz ileostomy procedure in a swine model of ITx, and investigated its feasibility for obtaining intestinal samples of both the graft and the recipient.. We performed ITx in 10 pairs of piglets, each weighing 15-20 kg. Procurement included an isolated segment of the small bowel, constituting a model of a living, related donor surgery. The recipient procedures included end-to-end anastomosis of vascular stumps, a proximal jejuno-jejunal anastomosis, and a distal modified Paul-Mikulicz ileostomy. The procedure differed from the classic Paul-Mikulicz ileostomy in that a common channel was created in a side-to-side fashion.. Vascular thrombosis occurred in three pigs, resulting in immediate loss of the graft. All other pigs underwent ITx successfully and survived for at least 1 wk (7-180 d). No pig experienced anastomotic leaks, ileus, or stoma-related complications. Moreover, this technique enabled us to obtain tissue samples of both the graft and the native ileum without disturbing the natural bowel conduit.. The modified Paul-Mikulicz ileostomy was feasible in a swine model of ITx. It facilitated the collection of intestinal samples of both the graft and the recipient.

Topics: Animals; Body Weight; Humans; Ileostomy; Immunosuppressive Agents; Intestinal Diseases; Intestine, Small; Living Donors; Male; Mesenteric Arteries; Mesenteric Veins; Parenteral Nutrition; Postoperative Period; Reperfusion; Swine; Tacrolimus; Transplantation, Homologous

The main component of the metabolic by-products of fermentation by Propionibacterium freudenreichii ET-3 is 1,4-dihydroxy-2-naphthoic acid (DHNA), which has a naphthoquinone skeleton, as in vitamin K2. This study showed that DHNA improved bone mass reduction with osteoporosis model mice caused by FK506.. Growth of the intestinal bacterium Lactobacillus bifidus is specifically facilitated by DHNA. The present study used osteoporosis model mice to investigate the effects of DHNA on bone remodeling.. FK506, an immunosuppressant, was used to prepare osteoporosis model mice. Thirty mice were divided into three groups: FK group, FK+DHNA group, and control group. In the FK group, FK506 was administered to induce bone mass reduction. In the FK-DHNA group, FK506 and DHNA were administered concurrently to observe improvements in bone mass reduction. To ascertain systemic and local effects of DHNA, we investigated systemic pathological changes in colon, kidney function and cytokine dynamics, and morphological and organic changes in bone and osteoclast dynamics as assessed by culture experiments.. Compared to the FK group without DHNA, colon damage and kidney dysfunction were milder for FK+DHNA group, and production of inflammatory cytokines (interleukin (IL)-1beta, IL-6 and tumor necrosis factor (TNF)-alpha) was more suppressed. Furthermore, compared to the group without DHNA, histological analyses and radiography showed that bone resorption was suppressed for the DHNA group. Culture experiments using osteoclasts from murine bone marrow showed osteoclast suppression for the DHNA group compared to the group without DHNA.. These results show that DHNA has some effects for improving bone mass reduction caused by FK506.

Topics: Animals; Body Weight; Bone Density; Bone Density Conservation Agents; Cells, Cultured; Colon; Disease Models, Animal; Drug Evaluation, Preclinical; Eating; Femur; Immunosuppressive Agents; Inflammation Mediators; Kidney; Male; Mice; Mice, Inbred ICR; Naphthols; Osteoclasts; Osteoporosis; Tacrolimus

Certain composite tissue allotransplants contain vascularized bone grafts (e.g., hand/forearm composite tissue allotransplants). The authors investigated the role of the vascularized bone graft within the hind-limb osteomyocutaneous flap in inducing tolerance.. Brown Norway and Lewis rats were used as composite tissue allotransplant donors and recipients, respectively. Experimental groups were as follows: group I, syngeneic controls (Lewis to Lewis); group II, allogeneic controls (both received no pretransplantation total body irradiation); and groups III, IV, and V, which received 5 mg of antilymphocyte globulin administered intraperitoneally (on days -1 and 10), 1 mg/kg of tacrolimus administered intraperitoneally (on days 0 to 10), and total body irradiation (600, 400, and 200 cGy, respectively, 1 day before composite tissue allotransplantation). Each Lewis rat in groups II, III, IV, and V received a composite tissue allotransplant on day 0 in the form of a Brown Norway hind-limb osteomyocutaneous flap. Different donor hematopoietic cell lineages in recipients' peripheral blood were assessed by flow cytometry on posttransplantation days 15, 30, 60, 90, 120, and 150. Secondary Brown Norway skin grafts in recipients with composite tissue allotransplant acceptance were performed at 150 days after transplantation.. Allotransplanted hind-limb osteomyocutaneous flaps produced chimerism and donor multilineage hematopoietic cells in groups III, IV, and V; composite tissue allotransplant acceptance rates in these groups were 37.5, 16.7, and 0 percent, respectively. Graft-versus-host disease occurred in 62.5 percent of group III recipients. Recipients with acute graft-versus-host disease produced a higher percentage of donor T cells compared with composite tissue allotransplant-accepting recipients (p < 0.05). Secondary Brown Norway skin graft acceptance in composite tissue allotransplant-accepting recipients confirmed durable tolerance.. Vascularized bone grafts contained within composite tissue allotransplants can autocreate chimerism and tolerance in rats with partial myeloablative tacrolimus-based conditioning.

Topics: Animals; Body Weight; Bone and Bones; Bone Marrow Cells; Bone Transplantation; Graft Rejection; Graft Survival; Graft vs Host Disease; Immune Tolerance; Immunosuppressive Agents; Male; Rats; Rats, Inbred BN; Rats, Inbred Lew; Skin Transplantation; Surgical Flaps; Tacrolimus; Transplantation Chimera; Transplantation Conditioning; Transplantation, Homologous

FK-506 is an immunosuppressant being widely used for allograft rejection cases in the present clinical scenario. Recently, the neuroprotective effect of FK-506 has also been reported against a number of neurodegenerative diseases in rodents. This study was designed to explore the possible protective effect of FK-506 and its interaction with nitric-oxide modulators against 3-nitropropionic acid (3-NP)-induced behavioural, biochemical, neurochemical, and mitochondrial alterations in striatum, cortex, and hippocampus regions of the brain. Systemic administration of 3-nitropropionic acid produces Huntington-like symptoms in rats. 3-NP (10 mg/kg) treatment for 14 days impaired locomotor activity, grip strength, and body weight. 3-NP treatment significantly raised malondialdehyde, nitrite concentration, depleted antioxidant enzymes (SOD and catalase), and levels of bioamines (dopamine and norepinephrine) in striatum, cortex, and hippocampus areas of rat brain. Significant alterations in mitochondrial enzyme complexes (I, II, and IV) activities and mitochondrial redox activity have also been altered significantly by 3-NP. Pretreatment with FK-506 (0.5, 1, and 2 mg/kg) significantly reversed these behavioral, biochemical, and cellular alterations. L-arginine treatment with a subeffective dose FK-506 (1 mg/kg) reversed the protective effect of FK-506. However, L-NAME pretreatment with FK-506 (1 mg/kg) potentiated the protective effect of FK-506. The present study shows that FK-506 attenuates 3-NP-induced neurotoxicity and nitric-oxide modulation might be involved in its protective action.

Topics: Animals; Behavior, Animal; Body Weight; Brain; Brain Chemistry; Disease Models, Animal; Huntington Disease; Male; Mitochondria; Motor Activity; Neuroprotective Agents; Nitric Oxide; Nitro Compounds; Oxidative Stress; Propionates; Rats; Rats, Wistar; Tacrolimus

We studied the effect of acute and sustained cyclosporine and tacrolimus on muscle sympathetic nerve activity (MSNA) in groups of healthy male volunteers.. Acute cyclosporine in normal dose (2.5 mg/kg) increased MSNA from 11 +/- 6 to 19 +/- 8 bursts/min (P < 0.05). Acute cyclosporine in high dose (10 mg/kg) increased MSNA from 13 +/- 6 to 25 +/- 4 bursts/min (P < 0.05) and increased heart rate and mean arterial pressure (heart rate from 64 +/- 8 to 74 +/- 6 b.p.m., MAP from 92 +/- 10 to 105 +/- 8 mmHg; both P < 0.05). Sustained cyclosporine (2.5 mg/kg b.i.d. for 2 weeks) suppressed MSNA from 14 +/- 6 to 8 +/- 7 bursts/min (P < 0.05). Blood pressure increased from 89 +/- 6 to 98 +/- 6 mmHg (P < 0.05). Body weight increased and plasma renin activity was suppressed. Acute tacrolimus in regular dose (0.05 mg/kg) and high dose (0.20 mg/kg) had no effect on MSNA and blood pressure. Sustained tacrolimus (0.05 mg/kg b.i.d. for 2 weeks) had no effect on blood pressure, body weight and plasma renin activity, but decreased MSNA from 14 +/- 6 to 8 +/- 5 bursts/min (P < 0.05).. Sympathetic overactivity plays a role in the acute hypertensive action of cyclosporine. Cyclosporine given during 2 weeks increases blood pressure and suppresses MSNA, possibly by volume retention. Tacrolimus, in the presently applied dosages, does not cause hypertension or sympathetic overactivity. However, sustained tacrolimus also suppresses sympathetic activity, the reason of which is unclear.

Topics: Blood Pressure; Body Weight; Calcineurin Inhibitors; Cyclosporine; Dose-Response Relationship, Drug; Heart Rate; Humans; Hypertension; Immunosuppressive Agents; Male; Renin; Sympathetic Nervous System; Tacrolimus

Pemphigus vulgaris (PV) is an autoimmune bullous disease caused by immunoglobulin G (IgG) autoantibodies against desmoglein 3 (Dsg3). We have generated an active disease mouse model for PV by adoptive transfer of Dsg3(-/-) lymphocytes. In this study, we investigated the benefits and limitations of this model as a tool to evaluate various immunosuppressive therapeutic strategies. We used the following three measurements to evaluate the effects of the drugs during the time course: Dsg3 enzyme-linked immunosorbent assay scores that represent the level of production of anti-Dsg3 IgG, body weight loss that reflects the severity of oral erosions and PV score that reflects the extent of skin lesions. We examined various immunosuppressive agents currently used to treat patients with PV model mice in preventive protocol. Cyclophosphamide almost completely suppressed the production of anti-Dsg3 IgG, development of body weight loss and the appearance of the PV phenotype in contrast with the control group without the drug. Azathioprine, cyclosporin A and tacrolimus hydrate also showed suppressive effects to various degrees. However, methylprednisolone and dexamethasone failed to show significant effects in contrast to the findings reported in humans. Knowing the advantages and limitations of this model will provide an important foundation for the future evaluation and development of novel therapeutic strategies.

Topics: Animals; Azathioprine; Body Weight; Cyclophosphamide; Cyclosporine; Desmoglein 3; Dexamethasone; Disease Models, Animal; Disease Progression; Female; Immunoglobulin G; Immunosuppressive Agents; Male; Methylprednisolone; Mice; Mice, Inbred C57BL; Mice, Knockout; Pemphigus; Phenotype; Tacrolimus

Tacrolimus (FK-506) is an immunosuppressant that binds to a specific immunophilin, resulting in the suppression of the cellular immune response during transplant rejection. Except for some alterations in the spermatozoa, testicular morphological alterations have not been described in rats treated with tacrolimus. In the present study, we purpose to evaluate if the treatment with tacrolimus at long term of follow-up interferes in the integrity of the seminiferous tubules.. Rats aging 42-day-old received daily subcutaneous injections of 1 mg/kg/day of tacrolimus during 30 (T-30) and 60 (T-60) days; the rats from control groups (C-30 and C-60) received saline solution. The left testes were fixed in 4% formaldehyde and embedded in glycol methacrylate for morphological and morphometric analyses while right testes were fixed in Bouin's liquid and embedded in paraffin for detection of cell death by the TUNEL method. The epithelial and total tubular areas as well as the stages of the seminiferous epithelium and the number of spermatocytes, spermatids and Sertoli cells (SC) per tubule were obtained.. In the treated groups, seminiferous tubules irregularly outlined showed disarranged cellular layers and loss of germ cells probably due to cell death, which was revealed by TUNEL method. In addition to germ cells, structural alterations in the SC and folding of the peritubular tissue were usually observed. The morphometric results revealed significant decrease in the number of SC, spermatocytes, spermatids and significant reduction in the epithelial and total tubular areas.. Tacrolimus induces significant histopathological disorders in the seminiferous tubules, resulting in spermatogenic damage and reduction in the number of Sertoli cells. A careful evaluation of the peritubular components will be necessary to clarify if these alterations are related to the effect of FK-506 on the peritubular tissue.

Topics: Animals; Body Weight; Immunosuppressive Agents; In Situ Nick-End Labeling; Male; Organ Size; Rats; Rats, Sprague-Dawley; Seminiferous Tubules; Tacrolimus; Testis

To prevent acute rejection episodes, it is important to reach adequate tacrolimus (TRL) exposure early after kidney transplantation. With a better understanding of the high variability in the pharmacokinetics of TRL, the starting dose can be individualized, resulting in a reduction in dose adjustments to obtain the target exposure. A population pharmacokinetic analysis was performed to estimate the effects of demographic factors, hematocrit, serum albumin concentration, prednisolone dose, TRL dose interval, polymorphisms in genes coding for ABCB1, CYP3A5, CYP3A4, and the pregnane X receptor on TRL pharmacokinetics. Pharmacokinetic data were prospectively obtained in 31 de novo kidney transplant patients randomized to receive TRL once or twice daily, and subsequently, the data were analyzed by means of nonlinear mixed-effects modeling. TRL clearance was 1.5-fold higher for patients with the CYP3A5*1/*3 genotype compared with the CYP3A5*3/*3 genotype (5.5 +/- 0.5 L/h versus 3.7 +/- 0.3 L/h, respectively). This factor explained 30% of the interindividual variability in apparent clearance (exposure). Also, a relationship between the pregnane X receptor A+7635G genotype and TRL clearance was identified with a clearance of 3.9 +/- 0.3 L/h in the A allele carriers versus 5.4 +/- 0.6 L/h in the GG genotype. Finally, a concomitant prednisolone dose of more than 10 mg/d increased the TRL apparent clearance by 15%. In contrast, body weight was not related to TRL clearance in this population. Because patients are typically dosed per kilogram body weight, this might result in underexposure and overexposure in patients, with a low and high body weight, respectively. This integrated analysis shows that adult renal transplant recipients with the CYP3A5*1/*3 genotype require a 1.5 times higher, fixed, starting dose compared with CYP3A5*3/*3 to reach the predefined target exposure early after transplantation.

Topics: Adult; Area Under Curve; Body Weight; Cytochrome P-450 CYP3A; Demography; Drug Administration Schedule; Drug Monitoring; Female; Hematocrit; Humans; Immunosuppressive Agents; Kidney Transplantation; Male; Metabolic Clearance Rate; Middle Aged; Polymorphism, Genetic; Prednisolone; Pregnane X Receptor; Prospective Studies; Randomized Controlled Trials as Topic; Receptors, Steroid; Serum Albumin; Tacrolimus

FK506 (tacrolimus), a potent immunosuppressive drug primarily used for reduction of allograft rejection in organ transplantation, also offers neuroprotection after central nervous system injury. FK506-mediated immunosuppression and neuroprotection may occur through different mechanisms that could affect neurological recovery and the severity of spinal lesions where cells transplantation therapy is combined with FK506 application. We assessed effects of long-term FK506 administration using the same dose regiment (1 mg/kg/day for 6 weeks) as is used in spinal cord transplantation studies following a balloon-compression induced spinal cord injury (SCI). Body weight and locomotor recovery quantified by the BBB (Basso-Beattie-Bresnehan) locomotor rating scale were evaluated for up to 42 days post-injury. The area of the preserved spinal cord tissue within a 13 mm segment of the spinal cord (lesion epicenter and 6 mm rostral-caudal) was examined histologically. The results showed no significant effects of FK506 on spinal cord tissue sparing or improvement of locomotor recovery. However, body weight fell significantly (P < 0.05) with FK506 treatment when compared with placebo from day 7 until sacrifice. In our experimental design, long-term FK506 treatment did not affect the parameters of outcome following balloon-compression SCI in the rat; however, multiple effects of FK506 should be taken into account when evaluating the outcomes in transplantation studies.

Topics: Animals; Body Weight; Male; Motor Activity; Nerve Tissue; Neuroprotective Agents; Rats; Recovery of Function; Spinal Cord; Spinal Cord Compression; Spinal Cord Injuries; Tacrolimus; Thoracic Vertebrae; Time Factors

We investigated the pharmacokinetics of oral tacrolimus in 31 hematopoietic cell transplant recipients, identifying 2 subgroups based on the differences between C(0) (trough) and C(max) (maximal) levels: group A (n = 21; 68%) with a C(max)-C(0) value of <10 ng/mL, and group B (n = 10; 32%) with a C(max)-C(0) value of >or=10 ng/mL. Although the C(0) and C(12) values were not significantly different between the 2 groups, the mean area under the concentration curve for 12 hours (AUC(0-12)) was significantly greater in group B than group A (200.9 +/- 36.3 vs 155.1 +/- 43.1 ng.h/mL; P < .05), and the mean half-life was significantly shorter in group B than group A (13.55 +/- 6.70 vs 18.17 +/- 6.30 hours; P < .05). Thus after the oral administration of tacrolimus, we observed a notably high AUC due to high peak level, which we were unable to predict simply by measuring the trough level. A pharmacokinetic analysis of each patient was essential to optimize the oral tacrolimus dose.

Topics: Administration, Oral; Adolescent; Adult; Area Under Curve; Body Weight; Female; Graft vs Host Disease; Hematopoietic Stem Cell Transplantation; Humans; Immunosuppressive Agents; Leukemia; Lymphoma; Male; Middle Aged; Multiple Myeloma; Tacrolimus; Young Adult

The aim of this study was to examine whether a limited sampling strategy (LSS) to allow the simultaneous estimation of the area under the concentration-time curves (AUCs) of tacrolimus and mycophenolic acid (MPA) calculated in the early stage after renal transplantation could be applied to maintenance phase pharmacokinetics. Seventy Japanese patients were enrolled. One year after transplantation, samples were collected just before and 1, 2, 3, 4, 6, 9, and 12 hours after tacrolimus and mycophenolate mofetil administration at 9:00 am and at 9:00 pm. The prediction formulas on day 28 (tacrolimus AUC 0-12 = 7.04 x C 0h + 1.71 x C 2h + 3.23 x C 4h + 15.19 and 2.25 x C 2h + 1.92 x C 4h + 7.27 x C 9h + 6.61, and MPA AUC 0-12 = 0.26 x C 0h + 2.06 x C 2h + 3.82 x C 4h + 20.38 and 1.77 x C 2h + 2.34 x C 4h + 4.76 x C 9h + 15.94) were applied to pharmacokinetic data obtained at 1 year. Three error indices [percent mean prediction error (ME), % mean absolute error, and percent root mean squared prediction error (RMSE)] were used to evaluate the predictive bias, accuracy, and precision. The predicted AUC 0-12 of tacrolimus and MPA at 3 time points, C 2h-C 4h-C 9h, showed higher correlation with the measured AUC 0-12 of tacrolimus and MPA (r2 = 0.817 and 0.789, respectively) in comparison with those at C 0h-C 2h-C 4h. The values for the prediction formulas for tacrolimus AUC at 1 year using the C 2h-C 4h-C 9h combination yielded less than 5% for %ME and 15% for %RMSE. The %ME and %RMSE values of the prediction formulas for tacrolimus AUC using the C 0h-C 2h-C 4h combination were 6.3% and 15.9%, respectively. The %ME and %RMSE values of the prediction formulas for MPA AUC at 1 year using the C 0h-C 2h-C 4h combination were 5.9% and 25.8%, respectively, and those for the C 2h-C 4h-C 9h combination were 4.9% and 21.2%, respectively. AUC 6-12/AUC 0-12 of MPA 1 year after transplantation was significantly lower than 28 days after transplantation. An LSS using C 2h-C 4h-C 9h seems to be applicable for predicting the AUC of tacrolimus and MPA at either posttransplantation stage. The enterohepatic circulation of MPA was significantly reduced 1 year after transplantation. Therefore, 1 year after transplantation, the estimation of the AUC 0-12 of MPA for the C 0h-C 2h-C 4h equations was imprecise. It is important that the LSS includes C 9h because it contains information on the secondary plasma peak of MPA.

Topics: Adult; Aged; Area Under Curve; Body Weight; Graft Survival; Humans; Immunosuppressive Agents; Kidney Transplantation; Middle Aged; Mycophenolic Acid; Regression Analysis; Tacrolimus; Young Adult

To investigate the tacrolimus dosage requirements and blood concentrations in adult-to-adult right lobe living donor liver transplantation (AALDLT) recipients with small-for-size (SFS) grafts.. During January 2007 and October 2008, a total of 54 cases of AALDLT with an observation period of 6 mo were enrolled in this study. The 54 patients were divided into two groups according to graft-recipient body weight ratio (GRBW): SFS grafts group (Group S, GRBW < 0.8%, n = 8) and non-SFS grafts group (Group N, GRBW > or = 0.8%, n = 46). Tacrolimus 12-hour blood levels and doses were recorded during weeks 1, 2, 3 and 4 and months 2, 3, 4, 5 and 6 in group S and group N. Meanwhile, acute rejection rates, liver and renal function test results, and the number of potentially interacting medications were determined at each interval in the two groups. A comparison of tacrolimus dosage requirements and blood levels were made weekly in the first month post-surgery, and monthly from months 2 to 6.. There were no differences in the demographic characteristics, acute rejection rates, liver and renal function test results, or the number of potentially interacting medications administered between the two groups. The tacrolimus dosage requirements in group S were significantly lower than group N at 2 wk (2.8 +/- 0.4 mg/d vs 3.6 +/- 0.7 mg/d, P = 0.006), 3 wk (2.9 +/- 0.7 mg/d vs 3.9 +/- 0.8 mg/d, P = 0.008), 4 wk (2.9 +/- 0.8 mg/d vs 3.9 +/- 1.0 mg/d, P = 0.023) and 2 mo (2.8 +/- 0.7 mg/d vs 3.8 +/- 1.1 mg/d, P = 0.033). Tacrolimus 12-h trough concentrations were similar between the two groups at all times except for 2 wk post-transplantation, when the concentrations were significantly greater in group S recipients than in group N recipients (11.3 +/- 4.8 ng/mL vs 7.0 +/- 3.8 ng/mL, P = 0.026).. SFS grafts recipients have significantly decreased tacrolimus dosage requirements compared with non-SFS grafts recipients in AALDLT during the first 2 mo post-surgery.

Topics: Adult; Aged; Body Weight; Female; Graft Survival; Humans; Immunosuppressive Agents; Liver Transplantation; Living Donors; Male; Middle Aged; Organ Size; Tacrolimus; Treatment Outcome; Young Adult

The purpose of the study was to assess the impact of age on the pharmacokinetics of immunosuppressive drugs.. One hundred and ten renal transplant recipients, including 12 elderly patients over 60 years of age, 57 middle-aged patients between 40 and 59 years and 41 young adult patients 20 to 39 years of age were studied. To evaluate dose-adjusted pharmacokinetics and cytochrome P450 (CYP) 3A5 pharmacogenetics, the concentrations of tacrolimus, mycophenolic acid (MPA), MPA glucuronide (MPAG) and prednisolone were measured at 1 month post-transplantation.. There were no differences in dose (D) and body weight (BW)-adjusted pharmacokinetic parameters of tacrolimus among the three groups. D/BW-adjusted C(max), C(0) and AUC(0-12) values of tacrolimus were significantly greater in patients with the CYP3A5*3/*3 genotype than in those with the CYP3A5*1 allele in young and middle-aged patients as previously reported, but not in the elderly. There were no significant differences in the D-adjusted pharmacokinetics of prednisolone and MPA among the three groups.. The aging process itself may have a small effect on the pharmacokinetics of tacrolimus, MPA, or prednisolone. However, a larger number of subjects need to be studied to confirm the impact of age on the CYP3A5 pharmacogenetics of tacrolimus in the elderly.

Topics: Adult; Age Factors; Aged; Aging; Analysis of Variance; Area Under Curve; Body Weight; Cytochrome P-450 CYP3A; Dose-Response Relationship, Drug; Enzyme Inhibitors; Female; Genotype; Humans; Immunosuppressive Agents; Kidney Transplantation; Male; Middle Aged; Mycophenolic Acid; Prednisolone; Tacrolimus; Time Factors

Although immunosuppressive treatments are available for acute cardiac rejection no viable treatment exists for long-term cardiac graft failure. Moreover, the extended use of calcineurin inhibitor immunosuppressants, the mainstay of current treatment for cardiac transplantation, leads to significant side effects such as nephrotoxicity and an increased risk of cardiac disease. Because some agents used in Traditional Chinese Medicine (TCM) have strong immunosuppressive effects coupled with low toxicity, we investigated the effect of Compound K (K), the synthesized analogue of highly unsaturated fatty acids from Isatis tinctoria L., either as a single treatment or combined with tacrolimus (FK-506) on acute cardiac allograft rejection. We compared the ability of K alone, or in combination with FK-506, to inhibit acute heart transplant rejection both in vitro and in vivo. We found that the inhibition of lymphocyte proliferation was positively correlated with K concentration. K significantly reduced IL-2 and IFN-gamma expression levels and significantly inhibited lymphocyte proliferation in both a lymphocyte transformation test and a mixed lymphocyte reaction (MLR). We also found that the inhibitory effect of a combination of K and a sub-therapeutic dose of FK-506 (SubFK-506) was stronger than that of full-dose FK-506 alone. Oral administration of K reduced acute cardiac allograft rejection in mice and had no apparent toxicity. In vivo, the immunosuppressive effect of K combined with a half-dose of FK-506 was equivalent to that of a full-dose of FK-506 alone. K combined with a half-dose of FK-506 reduced the expression levels of IL-2 and IFN-gamma (both within the graft and in the recipients' serum) more effectively than a full-dose of FK-506. These results show that K has significant immunosuppressive effects both in vitro and in vivo. When used as a combination therapy with FK-506 we see a powerful inhibition of rejection with no obvious toxic side effects. The mechanism of action is postulated to involve the inhibition of IL-2 and IFN-gamma expressions by lymphocytes, rather than the activation of Tr1 cells via the production of IL-10.

Topics: Animals; Body Weight; Cell Proliferation; Concanavalin A; Drug Synergism; Drugs, Chinese Herbal; Fatty Acids, Unsaturated; Female; Gene Expression; Graft Rejection; Graft Survival; Heart Transplantation; Immunosuppressive Agents; Interferon-gamma; Interleukin-10; Interleukin-2; Isatis; Lymphocyte Activation; Lymphocyte Culture Test, Mixed; Lymphocytes; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; T-Lymphocytes; Tacrolimus; Transplantation, Homologous

The aim of this study is to investigate the effect of the pharmacokinetic profile of tacrolimus on its pancreatic toxicity and efficacy in rats. For toxicity evaluation, doses of 0.03, 0.1, or 0.3 mg/kg/day were given once daily for 8 days in the bolus intravenous injection groups. In the continuous intravenous infusion groups, tacrolimus was infused using an Alzet osmotic mini-pump for 9 days at the same doses. Pancreatic insulin content decreased dose-dependently in both the bolus intravenous injection and continuous intravenous infusion groups, and there was no significant difference between the decreases caused by the two dosing regimens. At 0.03 mg/kg, continuous intravenous infusion did not cause glucose intolerance, but bolus intravenous injection induced significant and dose-dependent glucose intolerance. The pharmacokinetic data indicated that continuous intravenous infusion resulted in a sustained blood drug concentration with an area under the curve (AUC) similar to that obtained with the bolus administration at the same dose. For efficacy evaluation, donor ear grafts were transplanted to the lateral thoraxes of recipients. Tacrolimus doses of 0.01, 0.1, or 1 mg/kg/day were administered from day 0 to day 13. Both bolus intramuscular administration and continuous intravenous infusion prolonged skin allograft survival dose-dependently, and there was no significant difference between the median survival times of groups given the same doses. To summarize, the sustained-release of tacrolimus resulted in a steady blood drug concentration with an AUC similar to that of the bolus administration. In rats, it was better tolerated and just as efficacious as the bolus administration without producing a higher maximal blood concentration (Cmax). These results indicate that the sustained-release formulation has the potential to improve the safety of tacrolimus.

Topics: Animals; Blood Glucose; Body Weight; Dose-Response Relationship, Drug; Glucose Tolerance Test; Graft Rejection; Immunosuppressive Agents; Infusions, Intravenous; Injections, Intramuscular; Insulin; Male; Pancreas; Rats; Rats, Inbred F344; Rats, Sprague-Dawley; Skin Transplantation; Tacrolimus

The effect of tacrolimus on epididymal biochemical markers was investigated following single daily subcutaneous doses of 1, 2 and 3 mg kg(-1) day(-1) for 2 weeks to male adult rats. The tacrolimus 2 and 3 mg kg(-1) day(-1) groups showed a significant and dose-dependent decrease in sperm count in the cauda epididymis. Among tissue levels of L-carnitine, alpha-glucosidase and acid phosphatase, only L-carnitine level in the cauda epididymis was significantly reduced in the tacrolimus 3 mg kg(-1)day(-1) group. However, no significant difference was seen in the plasma L-carnitine. It was suggested that lowering of L-carnitine in the cauda epididymis was attributable to the adverse effect on epididymal function to transport and/or concentrate L-carnitine. Since L-carnitine has been reported to have antioxidant potential, antioxidant defense enzymes in the cauda epididymis such as superoxide dismutase (SOD), catalase, glutathione peroxidase and glutathione reductase were evaluated. The results showed no significant differences in activities, confirming that the treatment with tacrolimus did not affect the activities of these antioxidant enzymes. In conclusion, this study indicates that tacrolimus induces a decrease in L-carnitine level in the cauda epididymis, which is probably caused by impairment of epididymal function to transport and/or concentrate L-carnitine from bloodstream, and a decrease in sperm count.

Topics: Animals; Antioxidants; Biomarkers; Body Weight; Carnitine; Catalase; Dose-Response Relationship, Drug; Epididymis; Glutathione Peroxidase; Glutathione Reductase; Immunosuppressive Agents; Male; Organ Size; Rats; Rats, Inbred Strains; Sperm Count; Superoxide Dismutase; Tacrolimus

An animal model of post-transplant diabetes was induced in rats by treating them daily with 0.1 mg/kg body weight of tacrolimus (FK506) in two i.p. injections. Rats developed hyperglycaemia and glucose intolerance after 9 days of treatment. Pancreatic islets, isolated from treated rats on different days, showed a decreased capacity to secrete insulin in response to 20 mM glucose at days 7 and 14. This suppression of insulin secretion was preceded by a reduction of the islet insulin content on day 5 that was progressively decreasing until the end of the treatment (day 14). Islet content of insulin mRNAs, transcribed from rat insulin genes 1 and 2, was strongly suppressed, similar to the insulin content, at days 7 and 14. Islet mass was not strikingly modified by tacrolimus treatment: the DNA content was slightly decreased at the end (day 14) and the rate of islet cell apoptosis slightly increased. Tacrolimus-induced diabetes in the rat seems to be mainly provoked by a decreased insulin gene transcription with little or no alteration of islet mass. This explains that the observed suppression of all the islet and animal parameters studied was completely reversed 2 weeks after interrupting tacrolimus treatment.

Topics: Animals; Body Weight; Diabetes Mellitus, Experimental; Disease Models, Animal; DNA; Gene Expression Regulation; Insulin; Insulin Secretion; Islets of Langerhans; Male; Rats; Rats, Wistar; Tacrolimus

Tacrolimus is an immunosuppressive drug that causes glucose intolerance. On the other hand, ciprofloxacin, which is widely used in the treatment of infectious diseases, is known to cause hypoglycemia as a side effect. We investigated the effects of tacrolimus and ciprofloxacin on serum glucose and insulin levels in rats, as well as on insulin secretion and the viability of HIT-T15 cells. The rats received intraperitoneal injections of tacrolimus and/or ciprofloxacin for 1 week, and their arterial blood was sampled after the administration of glucose. HIT-T15 cells were cultured in the presence of tacrolimus and/or ciprofloxacin, and the insulin level in the supernatant was measured. Ciprofloxacin did not show a significant effect on serum glucose and insulin levels after multiple administrations in the rats. In contrast, rats in the tacrolimus treatment group showed low serum insulin and high serum glucose levels. Moreover, the coadministration of ciprofloxacin and tacrolimus resulted in higher glucose levels compared with tacrolimus alone 0.5 h after glucose stimulation. In addition, we observed that the rats administered tacrolimus and/or ciprofloxacin had low body weight and food intake. Tacrolimus caused a dose-dependent decrease in the viability of the HIT-T15 cells. Furthermore, both drugs were highly toxic to HIT-T15 cells. In contrast, tacrolimus alone and coadministration of the drugs resulted in no significant difference in insulin secretion. These results suggest that the cytotoxic effects of ciprofloxacin and tacrolimus cause a decrease in insulin secretion, leading to glucose intolerance.

Topics: Animals; Anti-Infective Agents; Body Weight; Cell Survival; Cells, Cultured; Ciprofloxacin; Cricetinae; Dose-Response Relationship, Drug; Eating; Glucose; Glucose Intolerance; Hypoglycemia; Immunosuppressive Agents; Insulin; Insulin-Secreting Cells; Male; Rats; Rats, Wistar; Tacrolimus

Tacrolimus (Tac) is mainly metabolized in the liver. The aim of this trial was to analyze Tac bioavailability after partial liver transplantation.. A total of 33 patients after right split liver grafting (n=8 living related, LRLT; n=8 cadaver split, CS) or full-size liver transplantation (n=17, FS) were included in this trial. All of them received Tac perorally with an initial dose of 2x5 mg/d. Dose adjustment was performed according to the Tac trough level (T0) with an initial target T0 levels of 12 to 15 ng/mL.. The time to reach target T0 levels tended to be lower (P=.05) in the split liver groups (LRLT: 2.8+/-1.6 days; CS: 2.1+/-0.9 days; FS: 4.5+/-3.2 days). In addition, mean Tac dose to maintain the target T0 level was significantly decreased (P=.01) in the split liver cohorts (LRLT: 5.8+/-1.1 mg/d; CS: 5.5+/-2.5 mg/d; FS: 9.8+/-3.9 mg/d). Only graft weight/standard liver volume ratio (r=.566, P=.02) and graft weight/body weight ratio (r=.709, P=.002) showed significant correlations with Tac maintenance doses in the split liver group.. Peroral Tac bioavailability was significantly higher after partial liver transplantation using the right hepatic lobe compared with full-size transplants. The volume of the split liver graft highly correlated with Tac maintenance therapy and should be used to calculate the most appropriate initial posttransplantation Tac dose.

Topics: Adult; Biological Availability; Body Weight; Cadaver; Female; Hepatectomy; Humans; Immunosuppressive Agents; Liver Transplantation; Living Donors; Male; Middle Aged; Organ Size; Tacrolimus; Tissue and Organ Harvesting; Tissue Donors

Ischemia-reperfusion (I-R) injury is poorly tolerated by fatty livers, most probably secondary to reduced cellular adenosine triphosphate (ATP) levels. We investigated the effectiveness of tacrolimus pretreatment on fatty liver I-R injury in obese Zucker rats. Tacrolimus (0.3 mg/kg, intravenously) was injected 24 hours before a 75-minute ischemic period and rats were sacrificed 6 hours later. Tacrolimus modified the response to I-R observed in obese Zucker rats, when compared to nontreated obese rats: a significant reduction in hepatocyte necrosis was associated with a significant increase in hepatocyte apoptosis. In addition, cell necrosis and apoptosis were significantly and inversely correlated in lean nontreated and treated obese Zucker rats following I-R. Tacrolimus also significantly increased the hepatic ATP levels, reduced in nontreated obese rats, toward values found in lean Zucker rat livers. This protective effect of tacrolimus was further confirmed in vivo by a significantly improved survival following pretreatment with tacrolimus, 24 hours prior to ischemia. In conclusion, in obese Zucker rat livers, tacrolimus pretreatment reversed the I-R injury toward the one found in lean Zucker rats. The correlations between ATP levels and the opposite changes in necrosis and apoptotic pathways strongly suggest a cause-effect relationship between tacrolimus and changes in ATP levels.

Topics: Animals; Biopsy, Needle; Body Weight; Disease Models, Animal; Fatty Liver; Immunohistochemistry; Liver Circulation; Liver Function Tests; Liver Regeneration; Male; Necrosis; Probability; Random Allocation; Rats; Rats, Zucker; Reference Values; Reperfusion Injury; Statistics, Nonparametric; Survival Rate; Tacrolimus; Time Factors

JTE-907, N-(benzo[1,3]dioxol-5-ylmethyl)-7-methoxy-2-oxo-8-pentyloxy-1,2-dihydroquinoline-3-carboxamide, is a selective cannabinoid CB2 receptor antagonist/inverse agonist. The anti-pruritic activity of JTE-907 was studied in NC mice with chronic dermatitis, a model of atopic dermatitis. The oral dose of JTE-907 (1 and 10 mg/kg/day), an immunosuppressant agent tacrolimus (1 mg/kg/day) and a glucocorticoid betamethasone 17-valerate (1 mg/kg/day) for 20 days suppressed the spontaneous scratching and cutaneous nerve activity of NC mice. JTE-907 (10, but not 1, mg/kg) and tacrolimus, but not betamethasone, tended to alleviate the dermatitis. Betamethasone inhibited the body weight gain. These results suggest that JTE-907 suppresses spontaneous itch-associated responses of NC mice without adverse effects such as weight loss.

Topics: Administration, Oral; Animals; Behavior, Animal; Betamethasone Valerate; Body Weight; Dermatitis, Atopic; Dioxoles; Disease Models, Animal; Dose-Response Relationship, Drug; Glucocorticoids; Immunosuppressive Agents; Male; Mice; Mice, Inbred Strains; Pruritus; Quinolones; Receptor, Cannabinoid, CB2; Severity of Illness Index; Skin; Tacrolimus

To identify the factors affecting tacrolimus apparent total body clearance (Cl/F [F = bioavailability]) in adult liver transplant recipients.. Population pharmacokinetic analysis using data from a retrospective chart review.. University-affiliated hospital in Seoul, South Korea.. Fifty-one adult liver transplant recipients who had received tacrolimus after transplantation.. Data on 35 adult liver transplant recipients for model building and 16 patients for model validation were obtained retrospectively. Population average parameter estimates of Cl/F and apparent volume of distribution (V/F) were sought by using the nonlinear mixed-effect model (NONMEM) program. A number of clinical covariates were screened for their influence on these pharmacokinetic parameters. The final optimal population model related Cl/F to total bilirubin, early (< or = 3 days) and late (> 35 days) postoperative days, international normalized ratio (INR), and graft:recipient weight ratio (GRWR). The NONMEM estimates indicated that the Cl/F of tacrolimus was decreased in patients with a small graft, hyperbilirubinemia, and a high INR. In addition, the Cl/F of tacrolimus almost doubled 4 days after transplantation, but decreased with an increase in duration of therapy after day 35. Mean prediction error and mean absolute prediction error were 0.26 and 3.78 ng/ml, respectively, for the validation sample. A final analysis in all 51 patients, which consisted of 1775 blood samples for concentration measurements, identified the following regression model: Cl/F (L/hr) = (0.36 + 2.01/POD * L) * TBIL(-0.23 (TBIL = 1 if TBIL level < or = 1.2 mg/dl, otherwise TBIL = TBIL level)) *49((if POD < or = 3 days)) * 0.75((if INR > 1.4)) * 0.86((if GRWR < or = 1.25%)) * WT, where L was 1 if postoperative day (POD) was greater than 35 days, otherwise L was 0; V/F was 568 L, TBIL was total bilirubin, and WT was body weight. The interindividual variabilities (coefficients of variation) in Cl/F and V/F were 35.35% and 68.12%, respectively. The residual variability was 3.14 ng/ml.. These findings could be useful to the health care provider for adjustment of tacrolimus dosage in adult liver transplant recipients with various clinical factors.

Topics: Adult; Aged; Asian People; Bilirubin; Biological Availability; Body Weight; Female; Humans; Immunosuppressive Agents; International Normalized Ratio; Liver; Liver Transplantation; Male; Medical Records; Metabolic Clearance Rate; Middle Aged; Models, Biological; Organ Size; Regression Analysis; Reproducibility of Results; Retrospective Studies; Tacrolimus; Time Factors

Cytochrome P450 3A5 (CYP3A5) and ABCB1 polymorphisms have been shown to influence tacrolimus (Tc) blood concentrations in the stable phase after organ transplantation. We hypothesized that Tc pharmacokinetics may be affected by genetic mutations subsequent to starting doses.. We retrospectively analyzed data from a cohort of 59 kidney transplant recipients, in whom CYP3A5 (intron 3) and ABCB1 (exons 12, 21 and 26) genotypes were correlated to dose- and weight-standardized Tc trough concentrations obtained after initial Tc doses. Renal function, expressed as glomerular filtration rate (GFR) (MDRD equation), on days 7 and 14 after transplantation was evaluated and its relationship with Tc concentrations was analyzed.. Dose- and weight-standardized Tc trough concentrations were lower in patients carrying the CYP3A5 *1 allele (p<0.01). There was no statistically significant association with ABCB1 polymorphisms. In a multivariate analysis, both the presence of at least one CYP3A5 *1 allele (p=0.006) and age at the time of transplantation (p=0.010) were significant independent variables affecting Tc trough blood concentrations standardized to the first dosages (model r2=0.23). GFR was not affected by Tc concentrations.. Prospective trials are needed to prove that a genetic approach to Tc pharmacokinetics and its related side effects during the early period after grafting may improve patient outcome.

Topics: Adult; Aged; ATP Binding Cassette Transporter, Subfamily B; ATP Binding Cassette Transporter, Subfamily B, Member 1; Body Weight; Cytochrome P-450 CYP3A; Cytochrome P-450 Enzyme System; Dose-Response Relationship, Drug; Drug Administration Schedule; Female; Humans; Immunosuppressive Agents; Kidney; Kidney Function Tests; Kidney Transplantation; Male; Middle Aged; Organic Anion Transporters; Polymorphism, Genetic; Retrospective Studies; Tacrolimus

Tacrolimus is an immunosuppressive drug with narrow therapeutic range and wide interindividual variations in its pharmacokinetics. P-glycoprotein (P-gp) plays an important role in the absorption metabolism of tacrolimus. The polymorphism C3435T of MDR1, the gene coding P-gp, may influence the expression and activity of P-gp. The aim of this study was to evaluate whether C3435T polymorphism was associated with the tacrolimus concentration/dose ratio. Sixty-six Chinese renal transplant patients enrolled in this study were surveyed for body weight and dosage and concentration of tacrolimus as well as MDR1 genotype by polymerase chain reaction followed by restriction fragment length polymorphism analysis. The results showed a significant association between tacrolimus levels per dose mg/kg/d and MDR1 gene C3435T polymorphism (P < .05). The CC patients displayed a lower tacrolimus level per dose than CT/TT patients. Pharmacogenetic methods might be employed prospectively to help dose selection and to individualize immunosuppressive therapy.

Topics: ATP Binding Cassette Transporter, Subfamily B, Member 1; Body Weight; China; Dose-Response Relationship, Drug; Genotype; Immunosuppressive Agents; Kidney Transplantation; Polymorphism, Single Nucleotide; Retrospective Studies; Tacrolimus

FK506 (tacrolimus), an immunosuppressive drug, improves quality of life (QOL) for patients with rheumatoid arthritis (RA). However, the mechanism of FK506 behind the improvement in QOL is still uncharacterized. To explain the improvement of QOL by FK506, we investigated the effect of FK506 on spontaneous locomotor activity in rats with collagen-induced arthritis (CIA). CIA was induced in 7- to 8-week-old female Lewis rats by immunization with bovine type II collagen. After initiation of paw inflammation (paw swelling, histopathological analysis), CIA rats were therapeutically administered FK506 or methotrexate (MTX) from day 15. Therapeutic treatment with FK506 ameliorated spontaneous locomotor activity without suppressing paw inflammation in CIA rats from day 27. FK506 also improved hyperalgesia and grip strength from day 27. Therapeutic treatment with MTX did not improve spontaneous locomotor activity, and simultaneously did not recover hyperalgesia or grip strength in CIA rats. Our results indicate that spontaneous locomotor activity in CIA rats correlates mainly with hyperalgesia and muscle strength, but not paw inflammation, implying that therapeutic treatment with FK506 ameliorates spontaneous locomotor activity via improvement of hyperalgesia and muscle strength in CIA rats.

Topics: Animals; Arthritis, Experimental; Body Weight; Female; Femur Head; Hyperalgesia; Immunosuppressive Agents; Inflammation; Methotrexate; Motor Activity; Muscle, Skeletal; Pain; Proteoglycans; Rats; Rats, Inbred Lew; Tacrolimus

Cytotoxic nitric oxide (NO) is produced during ischemia-reperfusion injury and acute and chronic rejection in allografts by expression of inducible (i) NO synthase (NOS). Therefore, continuous inhibition of iNOS may prevent early graft dysfunction and immune injury (rejection) and consequently improve graft survival. FR260330 is a potent and selective inhibitor of iNOS activity that works by preventing iNOS monomers from dimerization. In this study, the authors evaluated the effect of FR260330 in prevention of chronic rejection in a model of rat aortic allografts.. Male Lewis (LEW, RT1l) rats received male ACI (RT1a) aorta allografts or LEW aorta isografts. Fourteen groups (n > or = 6) were involved in this study. FR260330, tacrolimus, or both were administered orally for 14 or 90 days, according to protocol. The degree of intimal proliferation of graft aorta was determined by a computerized image system.. Both low and high doses of FR260330- or tacrolimus-treated grafts showed significantly decreased intima/(intima+media) ratios at day 90 compared with placebo controls. Combination therapy of low-dose FR260330 with low-dose tacrolimus produced a significant decrease of intima/(intima+media) ratios with intact endothelium compared with placebo controls. Anti-alpha-actin immunohistochemical staining demonstrated that one of the mechanisms of intimal proliferation is related to migration of vascular smooth muscle cells.. A selective inhibitor of NOS, FR260330 plays a protective role in chronic aortic allograft rejection in the rat. Combination therapy of low-dose FR260330 with tacrolimus produces significant protection of immune injury and may serve to improve long-term graft survival and function.

Topics: Actins; Animals; Aorta; Body Weight; Chronic Disease; Dose-Response Relationship, Drug; Drug Therapy, Combination; Enzyme Inhibitors; Graft Rejection; Graft Survival; Hyperplasia; Immunosuppressive Agents; Male; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Piperidines; Rats; Rats, Inbred ACI; Rats, Inbred Lew; Tacrolimus; Transplantation, Homologous; Tunica Intima; Tunica Media

Several other immunosuppressive agents still need to be found for rejection as alternatives to Tacrolimus in lung transplantation. We tried to elucidate the treatment effect of Multiglycosidorum tripterygii on tracheal allografts in comparison to that of Tacrolimus.. Treatment effect of agents on tracheal allografts, undergoing incomplete immunosuppression for 12 weeks after transplantation, was investigated using a heterotopic rat tracheal transplantation model. Treatments with Tacrolimus (1.0 or 1.5mg/kg per day), Multiglycosidorum tripterygii (150 or 225mg/kg per day) and a combination of Tacrolimus (1.0mg/kg per day) and Multiglycosidorum tripterygii (150mg/kg per day) were applied as a therapy for allografts. Four weeks after administering this therapy, the effect of each treatment was investigated by the morphologic assessment of transplants.. Treatment group with high doses of Multiglycosidorum tripterygii demonstrated a significantly better graft patency and lower cartilage dislocation than that without any treatment and tended to show better morphological findings than the other treatment groups, in addition to being safe. Some of allografts with high doses of Tacrolimus or Multiglycosidorum tripterygii therapy had a viable epithelium and viable tracheal glands in part, whereas the allografts with other treatments showed almost a completely denuded epithelium. High doses of Multiglycosidorum tripterygii therapy demonstrated less infiltration of mononuclear cells into the allografts, whereas other therapies showed a higher infiltration of such cells.. We conclude that high doses of Multiglycosidorum tripterygii may be a useful alternative to Tacrolimus as an immunosuppressant for rat tracheal allografts.

Topics: Animals; Body Weight; Cartilage; Epithelium; Glycosides; Graft Rejection; Immune Tolerance; Immunosuppressive Agents; Male; Models, Animal; Rats; Rats, Inbred BN; Rats, Inbred Lew; Tacrolimus; Trachea

Donor passenger leukocytes (DPLs) that migrate after organ transplantation stimulate the recipient immune system and normally cause rejection and graft vs. host reaction. However, DPLs also contribute to the unresponsiveness to the donor organ. The quantity and quality of these migrating cells are considered dependent on individual transplanted organs. We compared the DPLs of the liver, which might contain somatic stem cells, with those of intestinal grafts that have highly immunogenetic cells. To study DPLs over a long period, we used green fluorescent protein (GFP) transgenic (Tg) rats developed by us as donors.. We performed orthotopic liver transplantation (OLT) and small bowel transplantation (SBT) from GFP Tg rats to wild recipients. A short course of tacrolimus (0.64 mg/kg, intramuscularly) was used to prevent antigenicity of the GFP. The fate of the DPLs in the peripheral blood and the recipient bone marrow was monitored by flow cytometry. Using long-surviving recipients, the GFP(+) cells in the graft and various host immunologic organs were measured and characterized by immunohistochemical staining.. In both groups, the numbers of the GFP(+) cells in the peripheral blood increased transiently and then gradually decreased to undetectable levels. While no GFP(+) cells were identified in the long-surviving-recipient bone marrow, there were a few GFP(+) cells in the graft liver, graft mesenteric lymph nodes and the recipient spleen. These cells showed major histocompatibility complex (MHC) class II antigen. There was no significant difference in the migration patterns of the GFP(+) cells in the OLT and SBT rats.. In both the OLT and SBT groups, the DPLs migrated transiently in the recipient peripheral blood. A small numbers of MHC class II-positive DPLs were present at the graft site and in the host spleen, but not in the bone marrow. There were no significant differences in the migration patterns of the DPLs between the OLT and SBT rats over the long term.

Topics: Animals; Animals, Genetically Modified; Body Weight; Bone Marrow Cells; Cell Survival; Flow Cytometry; Genes, Reporter; Green Fluorescent Proteins; Immunohistochemistry; Intestine, Small; Leukocytes; Liver; Liver Transplantation; Luminescent Proteins; Lymph Nodes; Male; Rats; Rats, Wistar; Spleen; Survival Rate; Tacrolimus; Tissue Donors

The aim of this study was to determine if Bombesin (BBS) could help maintain the mucosal villus state in small bowel allografts without inducing acute rejection under immunosuppression.. Allogeneic small bowel transplantation was performed heterotopically in rats (n = 12). All rats received daily administration of FK506 from postoperative day 0 to day 28. On postoperative day 14, rats were divided into 2 groups of 6 rats each, and administered BBS or normal saline as a control. After 2 weeks of treatment, the rats were killed, and the graft mucosal villus state was evaluated by H&E staining, and crypt cell proliferation analysis was performed using immunohistochemistry with proliferative cell nuclear antigen (PCNA).. Villi were thin, and villus blunting was marked in the control group. The BBS group showed that the villi of the grafts were well maintained, and the volume of the lamina propria mucosa was adequately preserved. The PCNA labeling index of crypt cells in the control group was 40.06 +/- 3.36 (mean +/- SD) and that in the BBS group was 61.02 +/- 4.27. There was a significant difference (P <.001) between the 2 groups.. BBS maintained allograft epithelial cells and the volume of the lamina propria intestinal mucosa, stimulating proliferation of crypt cells under immunosuppression without inducing acute rejection.

Topics: Animals; Body Weight; Bombesin; Immunosuppressive Agents; Infusion Pumps, Implantable; Infusions, Intralesional; Intestinal Mucosa; Intestine, Small; Male; Peritoneal Cavity; Proliferating Cell Nuclear Antigen; Rats; Rats, Inbred BN; Rats, Inbred Lew; Tacrolimus; Transplantation, Homologous

Malononitrilamide 715 (FK778) is a new class of low-molecular-weight immunosuppressant that is a derivative of the active metabolite of leflunomide, A77 1726. In this study, the authors evaluated the combined effect of FK778 with tacrolimus in prevention of renal allograft rejection in Vervet monkeys.. Male Vervet monkeys were obtained from Caribbean Primates Ltd. Donor and recipient monkeys were from different breeding colonies. Eleven groups (n>or=4 per group) were involved in this study. FK778 and tacrolimus were administered orally for 60 days according to protocol.. Naive controls rejected renal grafts, with a median survival time (MST) of 8.0 days in group 1. When recipient monkeys were treated with tacrolimus 1.0 mg/kg/day in group 2 or FK778 2.5 mg/kg/day in group 3, the MST was 16.0 days (P=0.001) and 11.0 days (P=0.266), respectively. Combination therapy of these two agents at the same doses immediately after transplantation resulted in an MST of 25.0 days (P=0.016) in group 4. When tacrolimus was initiated immediately after transplantation and FK778 treatment was delayed until day 7 after surgery in group 5, recipient survivals were significantly prolonged to 38.0 days (P=0.02). These results were repeatable when FK778 5.0 mg/kg/day (9.0 days, P=0.544 in group 6) was combined with tacrolimus 1.0 mg/kg/day immediately after transplantation (8.0 days, P=0.339) in group 7, or when FK778 was delayed 7 days (60.0 days, P=0.002) in group 8. Furthermore, it was also repeatable when FK778 10 mg/kg/day was combined with tacrolimus 1.0 mg/kg/day with a 7-day delay.. A significant prolongation of renal allograft survival was produced when FK778 administration was delayed by 7 days combined with tacrolimus in Vervet monkeys.

Topics: Alanine Transaminase; Alkynes; Animals; Aspartate Aminotransferases; Body Weight; Chlorocebus aethiops; Dose-Response Relationship, Drug; Drug Administration Schedule; Drug Therapy, Combination; Graft Survival; Immunosuppressive Agents; Isoxazoles; Kidney; Kidney Transplantation; Liver; Male; Nitriles; Tacrolimus; Time Factors

The purpose of this study was to assess the overall results of recipients undergoing transplantation for biliary atresia (BA), according to age, surgical techniques, and transplant eras, and to identify the prognostic factors affecting outcome.. Between 1984 and 2000, 328 pediatric recipients with BA who underwent orthotopic liver transplantation (OLT) were reviewed. Median age at OLT was 1.5 years (range, 0.4-14.5 years). Kasai hepatoportoenterostomy (KHPE) had been previously performed in 285 (87%) children. Regarding surgical techniques, 125 (38%) children received a whole-liver graft, 128 (39%) received a reduced-size graft, 16 (5%) received a split-liver graft, and 59 (18%) received a living-related (LR) donor graft.. Overall actuarial patient survivals were 87%, 83%, and 81% at 1, 5, and 10 years, respectively. One-year patient survivals in children undergoing transplantation at the different age ranges were 85% (under 1 year), 86% (1-3 years), 83% (3-6 years), 100% (6-10 years), and 100% (beyond 10 years) (not significant). One-year patient survivals for the different transplant eras were 75% (1984-1988), 85% (1989-1992), 93% (1993-1996), and 98% (1997-2000) (P=0.0001). Multivariate analysis demonstrated that pretransplant recipient weight (P=0.004), indication for OLT (P=0.083), and age at OLT (P=0.024) predicted patient survival. The type of baseline calcineurin inhibitor (tacrolimus) and the age at OLT (beyond 6 years) were significantly associated with a better graft survival.. Best results in children undergoing transplantation beyond 6 years indicate the importance of performing a KHPE as the first therapeutic step in BA; innovative surgical techniques, particularly LR donor graft, allowed successful transplantation in infants with early failure of KHPE.

Topics: Adolescent; Aging; Biliary Atresia; Body Weight; Calcineurin Inhibitors; Child; Child, Preschool; Female; Graft Survival; Humans; Immunosuppressive Agents; Infant; Liver Transplantation; Living Donors; Male; Multivariate Analysis; Portoenterostomy, Hepatic; Prognosis; Survival Analysis; Tacrolimus; Treatment Outcome

Nonobese diabetic (NOD) mice develop autoimmune diabetes with features similar to those observed in the human disease. The concurrence of allorecognition and recurrence of autoimmunity might explain why most of the treatments successful in preventing islet allograft destruction in other nonautoimmune combinations often fail in NOD recipients. To assess the value of the NOD mouse model for the evaluation of treatments relevant to clinical islet transplantation, the authors have tested the effect of a protocol closely resembling the one successfully used in the Edmonton clinical trial on the survival of islet allografts in NOD mice.. C57BL/6 islets were transplanted under the kidney capsule of spontaneously diabetic NOD mice. Treatment consisted of a combination of rapamycin, tacrolimus, and anti-interleukin (IL)-2 monoclonal antibody. Control groups received each treatment alone, a combination of two agents, or no treatment.. Untreated animals invariably lost their graft within 13 days. Administration of rapamycin and tacrolimus significantly prolonged graft survival, with two of seven animals bearing a functional graft longer than 100 days. Addition of anti-IL-2 antibody therapy further improved graft survival, with six of eight grafts functioning longer than 100 days and two of eight grafts functioning longer than 200 days.. In view of the limited success obtained with other treatments in this model, the dramatic prolongation of graft survival observed in the authors' study, by using a therapy that mimics one successfully used in clinical trials, seems to validate the NOD mouse as a meaningful model for the study of therapeutic interventions for the prevention of islet graft loss.

Topics: Animals; Antibodies, Monoclonal; Body Weight; Cytokines; Diabetes Mellitus, Type 1; Drug Therapy, Combination; Female; Graft Survival; Immunophenotyping; Immunosuppressive Agents; In Vitro Techniques; Interleukin-2; Islets of Langerhans; Islets of Langerhans Transplantation; Lymphocytes; Mice; Mice, Inbred C57BL; Mice, Inbred NOD; Sirolimus; Tacrolimus; Transplantation, Homologous

Calcineurin-inhibitor nephrotoxicity plays a role in the pathogenesis of chronic allograft nephropathy by causing renal ischemia mediated by vasoconstrictive metabolites of the prostanoid pathway. The purpose of our study was to evaluate whether altering the prostanoid profile using juniper oil (JO) would afford renoprotection in rats treated with tacrolimus.. Diets supplemented with biologic oils (no supplementation, JO, fish oil [FO], safflower oil [SO], and arachidonic acid [AA]) were fed to five groups of rats for 5 weeks; during the last 2 weeks, tacrolimus was administered to all groups except for a control group of animals. At week 5, urinary prostaglandin (PG)F(2-alpha) and inulin clearances were measured. The rat kidneys were harvested to determine the renal cell membrane composition for arachidonic, eicosatrienoic, and eicosapentaenoic acids.. Both JO and FO completely reversed the decrease in inulin clearance seen with tacrolimus, the greatest effect being with JO (inulin clearance 15.1+/-3 vs. 6.0+/-1.1 ml/min in the nonsupplemented group; P<0.001); urinary PGF(2-alpha) excretion was also highest in the JO group (328+/-23 pg/mL, P<0.001 vs. the nonsupplemented group). Fatty acid membrane analysis showed greatest incorporation of eicosapentaenoic and eicosatrienoic acids in the JO- (5.7+/-0.6% and 3.1+/-0.4%, respectively) and FO- (8.1+/-0.7% and 2.8+/-0.6%, respectively) treated animals.. JO supplementation in tacrolimus-treated rats was associated with incorporation of vasodilatory prostanoids in the renal-cell membrane and elevated urinary PGF(2-alpha) excretion, and the precipitous fall in inulin clearance induced by tacrolimus was completely prevented. Whether this benefit will translate into a reduction in chronic allograft nephropathy remains to be determined. However, our preliminary data point towards the need for human trials.

Topics: Animals; Arachidonic Acid; Body Weight; Cell Membrane; Dinoprost; Drug Interactions; Fatty Acids; Fish Oils; Immunosuppressive Agents; Inulin; Kidney Diseases; Male; Plant Oils; Rats; Rats, Inbred Lew; Safflower Oil; Tacrolimus

Topics: Adult; Body Weight; Dose-Response Relationship, Drug; Humans; Immunosuppressive Agents; Liver Transplantation; Living Donors; Organ Size; Postoperative Period; Tacrolimus

Topics: Adolescent; Adult; Aged; Body Weight; Cardiovascular Diseases; Creatinine; Cyclosporine; Diabetes Mellitus; Female; Humans; Hypercholesterolemia; Hypertension; Immunosuppressive Agents; Kidney Function Tests; Liver Transplantation; Male; Middle Aged; Postoperative Complications; Prevalence; Retrospective Studies; Risk Factors; Tacrolimus; Transplantation, Homologous

Topics: ABO Blood-Group System; Adult; Antifungal Agents; Area Under Curve; Blood Group Incompatibility; Body Weight; Drug Interactions; Female; Fluconazole; Histocompatibility Testing; HLA-DR Antigens; Humans; Immunosuppressive Agents; Kidney Transplantation; Male; Retrospective Studies; Tacrolimus; Transplantation, Homologous

Topics: Adult; Body Weight; Dose-Response Relationship, Drug; Female; Heart Transplantation; Humans; Immunosuppressive Agents; Kidney Function Tests; Male; Racial Groups; Tacrolimus

Topics: Adolescent; Antilymphocyte Serum; Azathioprine; Body Weight; Cadaver; California; Child; Cyclosporine; Drug Therapy, Combination; Female; Humans; Kidney Transplantation; Living Donors; Male; Medical Records; Mycophenolic Acid; Racial Groups; Retrospective Studies; Tacrolimus; Tissue Donors

Topics: Area Under Curve; Body Weight; Drug Therapy, Combination; Female; Humans; Immunosuppressive Agents; Kidney Transplantation; Male; Mycophenolic Acid; Retrospective Studies; Sex Characteristics; Tacrolimus

Cardiotoxicity has been described in a group of pediatric patients receiving FK506 as a part of immunosuppression for orthotopic liver transplantation (OLT). Information regarding the cardiac pathology related to this agent is limited.. Among the first 975 liver transplants at our institution (1985-1995), autopsy hearts were available for 19 patients (14 adults and 5 children) who received FK506 for a minimum of 1 week prior to death. Patients with excessive alcohol use, significant coronary artery disease, valvular disease, diabetes mellitus, or pretransplant hypertension were excluded from analysis. We compared heart weight (HW), heart weight-to-body weight ratio (HW/BW), ventricular septal (VS) thickness with left ventricular (LV) thickness ratio (VS/LV), and cardiac histologic findings of 12 OLT patients (7 adults, 5 children) who received FK506 with a group of 75 OLT patients (48 adults, 27 children) who received Cyclosporine (CsA) and 20 (10 adults, 10 children) age-comparable control patients without OLT.. All FK506 and CsA children and adults had cardiomegaly by HW, HW/BW (P(FK506 peds) <0.024, P(CsA peds)<0.028, P(FK506 adults) <0.017, P(CsA adults)<0.006) and increased VS/LV ratio 1.25(FK506) (P <0.006) and 1.23(CsA) (P <0.006)(pediatric) and 1.09(FK506) (P <0.0122) and 1.21(CsA) (P <0.0009)(adults), compared with control.. Cardiomegaly by HW, HW/BW, and histology was uniformly present in both FK506 and CsA adult and pediatric OLT patients at autopsy. A relatively greater VS hypertrophy than LV was present in both transplant groups. We found no gross or histologic cardiac finding that separated these FK506 from CsA OLT patients at autopsy.

Topics: Adult; Autopsy; Body Weight; Cardiomegaly; Child; Cyclosporine; Female; Humans; Immunosuppressive Agents; Liver Transplantation; Male; Organ Size; Tacrolimus

It remains unclear how mineralocorticoids induce cardiac hypertrophy and fibrosis. Recently, activation of the calcium-dependent phosphatase, calcineurin, has been shown to induce cardiac hypertrophy. In the present study, we examine the role of calcineurin in mineralocorticoid-induced cardiac hypertrophy and fibrosis.. Uninephrectomized Wistar-Kyoto rats were placed on a 1.0% NaCl diet and treated with aldosterone (0.75 microg x h(-1)) for 6 weeks with or without the calcineurin inhibitors, FK506 (0.5 mg x kg(-1) x d(-1)) or cyclosporine A (10 mg x kg(-1) x d(-1)). The effect of the angiotensin II type 1 receptor antagonist, losartan (10 mg x kg(-1) x d(-1))on aldosterone-induced cardiac hypertrophy was also studied. Treatment with aldosterone increased the heart weight/body weight ratio, cardiomyocyte size, and collagen amount. The expression of mRNA of both type-III collagen and atrial natriuretic peptide in the heart were increased by aldosterone administration. Both calcineurin activity and its mRNA expression were also increased in aldosterone-induced hypertrophic heart. Treatment with losartan, FK506, or cyclosporine partially prevented aldosterone-induced cardiac hypertrophy and fibrosis.. These results suggest that calcineurin is involved in the development of cardiac hypertrophy and fibrosis induced by mineralocorticoid excess. Inhibition of calcineurin may therefore prevent cardiac hypertrophy and fibrosis in mineralocorticoid hypertension.

Topics: Aldosterone; Animals; Anti-Arrhythmia Agents; Antihypertensive Agents; Atrial Natriuretic Factor; Body Weight; Calcineurin; Calcineurin Inhibitors; Cardiomegaly; Collagen Type III; Cyclosporine; Enzyme Inhibitors; Fibrosis; Heart; Immunosuppressive Agents; Losartan; Male; Mineralocorticoids; Myocardium; Nephrectomy; Organ Size; Rats; Rats, Inbred WKY; RNA, Messenger; Sodium Chloride, Dietary; Tacrolimus

The immunosuppressant tacrolimus shows poor and variable bioavailability following oral administration in clinical use. Recently, the hepatic and intestinal metabolisms, or first-pass effect, of tacrolimus have been suggested to be responsible for its bioavailability. In the present study, we investigated the respective contribution of the jejunum and ileum to the first-pass effect of tacrolimus in rats.. The metabolism of tacrolimus in everted sacs of the duodenum, jejunum, and ileum was examined. Tacrolimus was administered intravenously or intraintestinally to sham-operated, jejunum-resected, or ileum-resected rats. Blood samples were collected over a 240-min period, and whole-blood tacrolimus concentrations were measured by semiautomated microparticle enzyme immunoassay. The pharmacokinetic parameters of tacrolimus in each group were estimated.. The metabolic activity of tacrolimus appeared to be the highest in the everted sacs of the duodenum. The bioavailability of tacrolimus in the jejunum- or ileum-resected rats was higher than that in sham-operated controls. On the other hand, the time to peak concentration in the jejunum-resected rats was about twofold slower than those in ileum-resected and sham-operated rats.. These results suggested that the first-pass effect of tacrolimus in the small intestine shows regional differences and the extraction of tacrolimus in the small intestine consists of the amount of extraction in the jejunum and ileum. In addition, the ileum rather than the jejunum as a graft of segmental small bowel transplantation would be useful to avoid the adverse effects of tacrolimus.

Topics: Administration, Oral; Animals; Biological Availability; Blotting, Western; Body Weight; Ileum; Immunosuppressive Agents; In Vitro Techniques; Intestinal Absorption; Jejunum; Male; Rats; Rats, Wistar; Tacrolimus

The new immunosuppressive agent sirolimus generally is combined in transplant patients with cyclosporine and tacrolimus which both exhibit cholestatic effects. Nothing is known about possible cholestatic effects of these combinations which might be important for biliary excretion of endogenous compounds as well as of immunosuppressants. Rats were daily treated with sirolimus (1 mg kg(-1) p.o.), cyclosporine (10 mg kg(-1) i.p.), tacrolimus (1 mg kg(-1) i.p.), or a combination of sirolimus with cyclosporine or tacrolimus. After 14 days a bile fistula was installed to investigate the effects of the immunosuppressants and their combinations on bile flow and on biliary excretion of bile salts, cholesterol, and immunosuppressants. Cyclosporine as well as tacrolimus reduced bile flow (-22%; -18%), biliary excretion of bile salts (-15%;-36%) and cholesterol (-15%; -47%). Sirolimus decreased bile flow by 10%, but had no effect on cholesterol or bile salt excretion. Combination of sirolimus/cyclosporine decreased bile flow and biliary bile salt excretion to the same extent as cyclosporine alone, but led to a 2 fold increase of biliary cholesterol excretion. Combination of sirolimus/tacrolimus reduced bile flow only by 7.5% and did not change biliary bile salt and cholesterol excretion. Sirolimus enhanced blood concentrations of cyclosporine (+40%) and tacrolimus (+57%). Sirolimus blood concentration was increased by cyclosporine (+400%), but was not affected by tacrolimus. We conclude that a combination of sirolimus/tacrolimus could be the better alternative to the cotreatment of sirolimus/cyclosporine in cholestatic patients and in those facing difficulties in reaching therapeutic ranges of sirolimus blood concentration.

Topics: Animals; Bile; Bile Acids and Salts; Biliary Fistula; Bilirubin; Body Weight; Cholagogues and Choleretics; Cholesterol; Common Bile Duct Diseases; Cyclosporine; Drug Interactions; Immunosuppressive Agents; Male; Rats; Rats, Wistar; Sirolimus; Tacrolimus; Triglycerides

Beginning 15 min after induction of intracerebral hemorrhage (ICH) by intrastriatal administration of collagenase, rats were treated intramuscularly with FK-506 (3 mg/kg) or with vehicle. Treatment was repeated daily for 7 days. MR imaging 1, 7, and 28 days post-ICH showed that treatment did not affect hematoma size or its subsequent resolution. Two days post-ICH, neutrophil infiltration around the hematoma was decreased in the FK-506-treated rats, as was the number of TUNEL-positive cells at the edge of the hematoma and in the peripheral region. The decreased inflammatory response was accompanied by functional improvement in the treated rats. The neurological deficit induced by the ICH (beam walking ability, postural reflex, spontaneous circling) was significantly decreased from 3 to 21 days post-ICH by treatment with FK-506. Skilled use of the forelimb ipsilateral to the ICH was improved and sensory neglect of the same limb was decreased 8-9 weeks post-ICH in rats treated with FK-506. However, neuronal loss assessed 9 weeks post-ICH was not different in the treated and untreated rats.

Topics: Animals; Apoptosis; Behavior, Animal; Body Weight; Brain; CD8-Positive T-Lymphocytes; Cerebral Hemorrhage; Corpus Striatum; Disease Models, Animal; Feeding Behavior; Immunosuppressive Agents; In Situ Nick-End Labeling; Inflammation; Male; Neutrophil Infiltration; Rats; Rats, Sprague-Dawley; Recovery of Function; Tacrolimus

To analyse the influence of covariates on the apparent clearance (CL) of tacrolimus in paediatric liver transplant recipients being converted from cyclosporin to tacrolimus.. Retrospective modelling study.. 18 children, 13 girls and 5 boys, aged 4 months to 16 years (median 9.1 years) who required conversion to tacrolimus because of acute or chronic rejection or cyclosporin toxicity.. 287 whole-blood tacrolimus concentrations from therapeutic drug monitoring were used to build a nonlinear mixed-effects population model (NONMEM program) for the apparent clearance of tacrolimus. Variables considered were age, total bodyweight (TBW), body surface area (BSA), time after initiation of treatment (T), gender, haematocrit (Hct), albumin (Alb), aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyl transpeptidase (gammaGT), alkaline phosphatase (ALP), bilirubin (BIL), creatinine clearance (CL(CR)) and dosage of concomitant corticosteroids (EST).. TBW, T, BIL and ALT were the covariates that displayed a significant influence on CL according to the final regression model: CL (L/h) = 10.4(TBW/70)3/4 x e(-0.00032 T) x e(-0.057 BIL) x (1 - 0.079 ALT). With this model, the estimates of the coefficients of variation were 24.3% and 29.5% for interpatient variability in CL and residual variability, respectively.. The proposed model for tacrolimus CL can be applied for a priori dosage calculations, although the results should be used with caution because of the unexplained variability in the CL. We therefore recommended close monitoring of tacrolimus whole blood concentrations, especially within the first months of treatment. The best use of the model would be its application in dosage adjustment based on therapeutic drug monitoring and the Bayesian approach.

Topics: Adolescent; Adrenal Cortex Hormones; Alanine Transaminase; Bilirubin; Body Weight; Child; Child, Preschool; Drug Monitoring; Female; Graft Rejection; Humans; Immunosuppressive Agents; Infant; Liver Transplantation; Male; Metabolic Clearance Rate; Nonlinear Dynamics; Regression Analysis; Retrospective Studies; Tacrolimus

Topics: Adult; Antilymphocyte Serum; Azathioprine; Body Weight; Drug Therapy, Combination; Female; Heart Transplantation; Humans; Immunosuppressive Agents; Kidney Function Tests; Liver Function Tests; Male; Middle Aged; Postoperative Period; Regression Analysis; Tacrolimus; Time Factors

Hypertension and hyperlipidemia are more prevalent after liver transplantation with cyclosporine as the primary immunosuppressive agent compared with tacrolimus. To determine whether blood pressure, serum lipid level, or weight improves when patients switch immunosuppression therapy, we retrospectively studied 26 liver transplant recipients with stable graft function who had been converted from cyclosporine to tacrolimus therapy with a median follow-up of 8 months. One of the 26 patients developed pruritus necessitating withdrawal of tacrolimus. The results therefore concern the remaining 25 patients. With the exception of a small decrease in bilirubin level (P <.05), there was no difference in graft or renal function after conversion. Mean systolic blood pressure decreased from 158 +/- 25 to 148 +/- 22 mm Hg over a mean of 8 +/- 3 months after conversion to tacrolimus (P =.015), whereas mean serum cholesterol level decreased from 5.3 +/- 0.9 to 4.9 +/- 0.9 mmol/L (P =.01). Sixty-eight percent of the patients lost weight, from a mean of 79.4 +/- 22.6 to 76.1 +/- 20.1 kg, in the 11 months after switching to tacrolimus therapy (P =.024). Serum triglyceride and blood glucose levels did not change, and no patient developed diabetes mellitus after conversion. These results indicate that switching from cyclosporine to tacrolimus can reduce blood pressure, serum cholesterol level, and weight after liver transplantation.

Topics: Blood Pressure; Body Weight; Cyclosporine; Female; Humans; Hyperlipidemias; Hypertension; Immunosuppressive Agents; Lipids; Liver Transplantation; Male; Middle Aged; Retrospective Studies; Risk Factors; Tacrolimus

Despite the beneficial immunosuppressive effects of FK506 during small intestine transplantation, FK506 appears to have direct toxic effects on the intestine. The mechanisms of FK506-induced intestinal damage is unclear, and whether nitric oxide (NO) is involved in the mechanism has not been well defined. This study was designed to evaluate the effects of NG-Nitro-L-arginine methyl ester (L-NAME), an inhibitor of NO synthase, on small intestinal damage in rats treated with FK506.. Wistar rats weighing 240-260 g, aged 11 weeks, were administered FK506 (5 mg/kg/day i.m) and/or L-NAME (5 mg/dl in drinking water) for 10 days. Body weight gain, diarrhoea and mortality were observed during experiment. At the end of experiment, the intestinal specimens were excised for histological evaluation. In addition, the effects of L-aginine treatment (1 g/dl in drinking water) were evaluated in this study.. L-NAME administration time-dependently induced diarrhoea and high mortality in the rats treated with FK506. At the end of 10 days treatment, 7 of 12 rats (58.3%) suffered from diarrhoea and 5 of 12 rats (41.7%) died in the FK506 + L-NAME group (vs. FK506 group, p = 0.05). A significant loss of body weight was also found in the rats treated with FK506 + L-NAME (-52.2 +/- 28.8 g, in FK506 + L-NAME group vs. -14.3 +/- 8.7 g in FK506 group, p = 0.001). In parallel with the severe diarrhoea and high mortality, the loss of villi, hemorrhage and necrosis (grade 5 of pathological damage) was seen in the small intestinal mucosa of rats treated with FK506 + L-NAME. L-arginine treatment in part prevented diarrhoea, mortality and pathological damage of small intestinal mucosa induced by L-NAME.. Inhibition of NOS induces intestinal mucosal damage and increases mortality in rats treated with FK506. L-arginine treatment can in part prevent the injury induced L-NAME. The present study suggests that NO, as an important protective factor, may be involved in the FK506-induced intestinal damage.

Topics: Administration, Oral; Animals; Body Weight; Diarrhea; Drinking; Drug Antagonism; Enzyme Inhibitors; Immunosuppressive Agents; Injections, Intramuscular; Intestinal Mucosa; Jejunum; Longevity; Male; NG-Nitroarginine Methyl Ester; Nitric Oxide Synthase; Rats; Rats, Wistar; Tacrolimus; Time Factors

Pancreas grafts do not survive for lengthy periods, especially in a high-responder rat combination. Recent data indicated that a combined spleen/pancreas graft protects against acute graft rejection and induces donor-specific tolerance. In this study, we performed a combination spleen/pancreas transplantation using high-dose tacrolimus in a high-responder rat combination of DA (RT1a) to LEW (RT1) and induced permanent survival in the few recipient rats. In these recipients, there was no difference in the mixed lymphocyte reaction (MLR) of the recipients when compared with that of the naive LEW splenic cells, but MLR inhibition by the serum from the recipients was significantly decreased. We also performed immunoblotting and detected a protein that has an affinity for the anti-DA class antibody. This protein may be an anti-idiotypic antibody and contribute to donor- and tissue-specific tolerance.

Topics: Animals; Antibodies, Anti-Idiotypic; Body Weight; Diabetes Mellitus, Experimental; Dose-Response Relationship, Drug; Graft Rejection; Graft Survival; Histocompatibility Antigens; Immunosuppressive Agents; Islets of Langerhans; Lymphocyte Culture Test, Mixed; Pancreas Transplantation; Rats; Rats, Inbred Lew; Rats, Inbred Strains; Spleen; Tacrolimus

FTY720 is a new immunosuppressant agent and selectively decreases the number of circulating lymphocytes. In this study, we compared the effects of FTY720 with those of tacrolimus on experimental autoimmune myocarditis (EAM) in rats. A significant decrease in circulating lymphocyte counts was noted after a single administration of FTY720 in normal rats. At day 0, 7-week-old male Lewis rats were immunized with purified porcine cardiac myosin emulsified in complete Freund's adjuvant. FTY720 or tacrolimus was administered intraperitoneally daily. The number of myocarditis-affected areas in the FTY720 treatment groups with doses of 0.1 mg/kg/ day was significantly lower than those in control groups at days 14 and 28. In addition, at day 28, the myocarditis-affected areas in the FTY720 treatment group were significantly smaller than those in the tacrolimus treatment group receiving the same dose. Effects of early administration (days 0-10) and delayed administration (days 11-20) of FTY720 also were examined. At day 28, the myocarditis-affected areas in the early therapy group were significantly lower than those in the control group. In conclusion, we demonstrated that the development of EAM could be prevented by FTY720. These data also indicated that lymphocyte-mediated immunity is critically involved in the development of EAM.

Topics: Analysis of Variance; Animals; Autoimmune Diseases; Body Weight; Fingolimod Hydrochloride; Immunosuppressive Agents; Injections, Intraperitoneal; Lymphocyte Count; Lymphocytes; Male; Myocarditis; Organ Size; Propylene Glycols; Rats; Rats, Inbred Lew; Sphingosine; Tacrolimus

Our previous studies confirmed that tacrolimus (FK506) and sirolimus [rapamycin (RAPA)], in combination, are not antagonistic but are synergistic in the prolongation of heart and small bowel grafts in the rodent. The aim of this study was to confirm further the synergistic effect of combined FK506 and RAPA in the more clinically relevant model, kidney transplantation in monkeys.. A total of 60 male Vervet monkeys were randomly assigned to 10 groups (n> or =5). Monkeys with renal allografts were treated with different doses of FK506 and/or RAPA orally for 60 days. Graft survival, body weight, clinical biochemistry determinations, oral glucose tolerance test, trough levels of the two drugs, and histopathology were investigated.. Low doses of FK506 (1 or 4 mg/kg) combined with RAPA (0.5 mg/kg) produced synergistic effect in the prolongation of renal graft survival [combination index (CI) = 0.292, 0.565]. There were no additive or synergistic drug-associated toxicities such as hyperglycemia, nephrotoxicity, and hyperlipidemia. There also was no pharmacological antagonism.. Concomitant therapy of low-dose (drug-optimal) FK506 and RAPA produced a synergistic effect in the prolongation of kidney allograft survival in Vervet monkeys without additive drug-associated toxicities.

Topics: Animals; Body Weight; Chlorocebus aethiops; Drug Synergism; Drug Therapy, Combination; Glucose Tolerance Test; Graft Rejection; Graft Survival; Immunosuppressive Agents; Kidney; Kidney Transplantation; Male; Sirolimus; Tacrolimus; Time Factors

Steroid withdrawal after renal transplantation and cyclosporine-based immunosuppression enhances growth in children, but this practice is not widely employed because of a 50%-60% rate of rejection, graft dysfunction, or graft loss. The current study evaluates growth and renal function after withdrawal and discontinuation of steroids within 1 year of transplantation in 52 children receiving tacrolimus (FK-506)-based immunosuppression. Height Z-score, weight-for-height index (WHI), and body mass index (BMI), as well as graft loss and calculated creatinine clearance as a measure of glomerular filtration rate (GFR), were assessed. Children were divided into three groups according to age at transplantation: group I, 16 children aged 0-5 years; group II, 17 children aged 6-12 years; group III, 19 children aged 13-16 years. Significant and sustained improvement in height occurred in groups I and III, with Z-scores increasing by 1.51 and 1.57 standard deviations at 3 years after transplantation compared with the Z-score at transplantation (P<0.02). Mean WHI values remained near 100% in groups I and III, and significantly increased above 100% only in group II at 2 years after transplantation. Although actual BMI scores improved significantly in groups II and III at both 2 and 3 years post transplantation (P<0.05), when BMI scores were adjusted for height age, none of these groups had values >95% denoting obesity. Failure of steroid withdrawal, defined as reinstitution of steroids, graft dysfunction, or graft loss, occurred in 9 of 68 (13%) children who underwent steroid withdrawal at any time after transplantation, and resulted in graft dysfunction or graft loss in 5 (7%). Over a 3-year period, rates of renal dysfunction, as manifested by >50% rise in the serum creatinine level above baseline, or graft loss were lower in these 68 children compared with 8 children who never had steroid withdrawal (P<0.05). Mean GFR at 3 years after transplantation ranged from 96 to 102 ml/min per 1.73 m2 in all three steroid withdrawal groups, and remained stable during the 3 years of follow-up. These data indicate that steroid withdrawal enables normalization of growth without obesity, and without imposing an excessive risk for graft dysfunction or graft loss.

Topics: Adolescent; Body Height; Body Mass Index; Body Weight; Child; Child Development; Child, Preschool; Glucocorticoids; Graft Rejection; Humans; Immunosuppressive Agents; Infant; Infant, Newborn; Kidney; Kidney Transplantation; Methylprednisolone; Postoperative Period; Prednisone; Retreatment; Tacrolimus

The aim of the present study was to investigate a systemic induction of bone formation in rats by immunosuppression with FK506 (1 mg/kg body weight intraperitoneally [ip]) in a model of osteoinduction of isogeneic and xenogeneic demineralized bone matrix (DBM) for a period of 28 days. In particular, alterations of in vitro cytokine synthesis and changes of lymphocyte subsets were studied. DBM was implanted intramuscularly in the abdominal wall of Lewis rats (seven per group). Blood was sampled on days -7, 0, 7, and 28 for determination of in vitro tumor necrosis factor a (TNF-alpha) synthesis and lymphocyte subsets by flow cytometry (CD3+, CD4+, CD8+, CD45+, ED9+, and Ia+ antibodies). Ossicles of de novo formed bone and the tibias were removed on day 28 after double tetracycline labeling for histomorphometric analysis. Immunosuppression with FK506 significantly decreased lipopolysaccharide (LPS)-stimulated in vitro cytokine synthesis after 7 days and 28 days (p < 0.05). Compared with control animals FK506 treatment significantly increased the volume of induced bone in isogeneic (2.1 +/- 0.3 mm3 vs. 10.8 +/- 0.9 mm3) and xenogeneic (O mm3 vs. 4.7 +/- 0.8 mm3) DBM. Bone histomorphometry of the tibias revealed that immunosuppression increased both bone formation and bone resorption, accompanied by a significant reduction in the relative trabecular area (Tb.Ar). FK506 caused a decrease in the counts of CD8+ T cells probably because of destruction or dislocation of these cells. This suggests that the amount of CD8+ cells and the degree of T cell activation in terms of mean fluorescence intensity (MFI) may be associated with bone metabolism. In support of this, statistical analysis revealed a significant positive correlation between parameters of bone formation as well as bone resorption and the CD4+/CD8+ ratio. There was a significant negative correlation between parameters of remodeling of the metaphysis of the tibia and induced bone volume (BV), respectively, and MFI values of CD3+/Ia+ cells. These findings suggest an important role of T lymphocytes in bone formation and bone resorption in vivo. FK506 caused a marked increase of bone formation in DBM. However, the conclusion that immunosuppression increases fracture healing warrants further investigation.

Topics: Alkaline Phosphatase; Animals; Antigens, CD; Body Weight; Bone Development; Bone Matrix; Bone Resorption; Calcification, Physiologic; Cell Differentiation; Cytokines; Immunosuppressive Agents; Lymphocyte Subsets; Rabbits; Rats; Rats, Inbred Strains; Tacrolimus; Tibia; Transplantation, Heterologous; Transplantation, Isogeneic

Topics: Animals; Body Weight; Epidermal Growth Factor; Glucose; Immunosuppressive Agents; Intestinal Absorption; Intestinal Mucosa; Jejunum; Male; Postoperative Period; Rats; Rats, Inbred BN; Rats, Inbred Lew; Tacrolimus; Transplantation, Homologous

Posttransplantation osteopenia leading to osteoporosis induced commonly by treatment with immunosuppressants including cyclosporine (CsA) is a severe complication and results in lowering the quality of life in patients receiving organ transplantation. FK506 is a newly developed immunosuppressant and is currently being used for the prevention of rejection after organ transplantation. In this study, to investigate whether FK506 as well as CsA would cause osteopenia or not, we evaluated the effect of FK506 on bone mineral density and several parameters relevant to bone metabolism in comparison with that of CsA using normal rats.. Ten-week-old male Sprague-Dawley rats were treated with FK506 (vehicle, 1 mg/kg, and 3.2 mg/kg) or CsA (vehicle, 10 mg/kg, and 32 mg/kg) by daily oral gavage for 28 days. Bone mineral density of the femur, plasma insulin-like growth factor I (IGF-I), and urinary deoxypyridinoline were determined by peripheral quantitative computerized tomography, radioimmunoassay, and enzyme-linked immunosorbent assay, respectively.. The reduction in bone mineral density of the femur was observed in both FK506- and CsA-treated rats. The reduction in CsA-treated rats, however, was statistically significant and strikingly severe, whereas that in FK506-treated rats was much less severe than CsA. Plasma IGF-I levels were significantly elevated in FK506-treated rats but not in CsAtreated rats. Urinary deoxypyridinoline levels were unchanged in FK506-treated rats but elevated in CsA-treated rats.. Compared with CsA, FK506 does not appear to induce severe osteopenia by high-turnover bone metabolism in the rat by mediating via IGF-I induction in part. The results suggest that FK506 may exert favorable effects on bone metabolism in patients with organ transplantation compared with CsA. To assess this idea, further clinical investigations focused on bone metabolism will be required.

Topics: Amino Acids; Animals; Bile Acids and Salts; Bilirubin; Biomarkers; Body Weight; Bone Density; Cyclosporine; Immunosuppressive Agents; Insulin-Like Growth Factor I; Male; Rats; Rats, Sprague-Dawley; Tacrolimus

Sodium-depletion in rats reproduces functional and morphological tacrolimus nephrotoxicity observed in man. Potent diuretics induce sodium-depletion. Our objective was to determine the effect of a loop diuretic furosemide on tacrolimus-mediated functional and pathological impairment of the kidney in rats. Sprague-Dawley rats were divided into four groups; group 1, rats received vehicle (saline) only; group 2, rats were treated with tacrolimus (1 mg/kg body weight) and furosemide (5 mg/kg body weight); group 3, rats were treated with tacrolimus alone; and group 4, rats were treated with furosemide (5 mg/kg body weight) alone. On day 28, tail blood pressure was measured and the rats were placed in metabolic cages for urine collection. After 24 hr the rats were sacrificed. Tacrolimus alone tended to cause growth retardation, hypotension, hypomagnesemia and a rise in blood urea nitrogen. Furosemide co-administration enhanced the effects of tacrolimus on hypotension, hypomagnesemia and a rise in blood urea nitrogen. The renal histology characterized by cytoplasmic vacuolization of the proximal tubules was not different between the rats treated with both tacrolimus and furosemide and the rats treated with tacrolimus alone. A strong immunostaining for FKBP-12, a tacrolimus-binding protein, was observed in the medulla of the kidneys of rats treated with tacrolimus either with or without furosemide. These results indicate that furosemide further augments tacrolimus induced impairment in kidney function, and that furosemide should be used with discretion in patients on tacrolimus therapy.

Topics: Animals; Blood Pressure; Blood Urea Nitrogen; Body Weight; Diuretics; Drug Synergism; Furosemide; Kidney; Kidney Diseases; Rats; Rats, Sprague-Dawley; Renin; Tacrolimus

Topics: Animals; Body Weight; Glucose; Hepatectomy; Immunosuppressive Agents; Leukocyte Count; Liver Function Tests; Liver Transplantation; Male; Mitochondria, Liver; Mitochondrial Swelling; Neutrophils; Rats; Rats, Inbred ACI; Rats, Inbred Lew; Tacrolimus; Tissue and Organ Harvesting; Transplantation, Homologous

Topics: Age Factors; Blood Loss, Surgical; Body Height; Body Weight; Dose-Response Relationship, Drug; Family; Humans; Immunosuppressive Agents; Infusions, Intravenous; Liver; Liver Transplantation; Living Donors; Regression Analysis; Tacrolimus

Prevention of rejection and preservation of graft function remain as obstacles to clinical small intestinal transplantation (SIT). This study evaluated the effects of combined immunosuppressive agents (FK506, Rapamycin, and Mycophenolate Mofetil) on intestinal function and animal well being.. Screening for additive toxicity was done in experiment one (D1, n = 10); doses were: FK506 0.3 mg/kg/d, Rapamycin 2 mg/kg/d, and Mycophenolate Mofetil 20 mg/kg/d, orally once daily. Control animals (C1, n = 10) received equivalent vehicle. In the second phase of the experiment, the effect of an additional parenteral treatment phase was investigated, with drug treated animals (D2, n = 6) received FK506 0.3 mg/kg, Rapamycin 1 mg/kg, and Mycophenolate Mofetil 10 mg/kg sq q12h for 1 week followed by FK506 3 mg/kg, Rapamycin 1 mg/kg, and Mycophenolate Mofetil 10 mg/kg p.o. q12h for 4 weeks. Control animals (C2, n = 6) received equivalent vehicle. Parameters followed were weight gain, nutrient absorption, drug levels and nutrient transport in vitro.. Controls grew normally, while weight gain was significantly reduced in drug treated animals: This was paralleled by a reduction in dietary fat absorption. Drug levels were low to therapeutic for all drugs in both experiments; FK506 appeared to affect Rapamycin and Mycophenolate Mofetil metabolism, increasing levels of both as FK506 doses increased. Nutrient transport was either not effected (D1) or increased (D2).. We conclude that low dose combination immunosuppressive therapy inhibits weight gain, without affecting absorption of dietary energy, or adversely affecting glucose transport. We postulate a systemic metabolic cause, which requires additional investigation at the cellular level; additional studies are also required to determine if the additive immunosuppression outweigh the side effects for SIT.

Topics: 3-O-Methylglucose; Animals; Body Weight; Drug Therapy, Combination; Glucose; Ileum; Immunosuppressive Agents; Intestinal Absorption; Intestine, Small; Jejunum; Male; Mycophenolic Acid; Rats; Sirolimus; Tacrolimus

Renal toxicity is a serious side effect of therapy with tacrolimus (FK506), an immunosuppressive agent administered to renal transplant recipients. We investigated the effect of hepatocyte growth factor (HGF) on tacrolimus-induced nephrotoxicity in spontaneously hypertensive rats (SHR). After a right nephrectomy, rats received a continuous perfusion of either HGF in a dose of 5 microg/kg daily (tacrolimus + HGF group) or normal saline (tacrolimus group) into the left renal artery at a rate of 1 microl/h for 7 days after surgery. Tacrolimus was injected intramuscularly in a dose of 4 mg/kg daily for 10 days after surgery. HGF significantly inhibited the tacrolimus-induced increase in the serum creatinine (SCr) level (P < 0.05). HGF also prevented the tacrolimus-induced loss in body weight. The bromodeoxyuridine (BrdU) index was significantly higher in kidney specimens from the tacrolimus + HGF group. These findings suggest that HGF induces the regeneration of renal tubular cells and suppresses tacrolimus-induced renal toxicity in SHR.

Topics: Animals; Body Weight; Creatinine; Hepatocyte Growth Factor; Humans; Hypertension; Immunosuppressive Agents; Injections, Intramuscular; Kidney; Kidney Tubules; Lymphocyte Culture Test, Mixed; Lymphocytes; Mitotic Index; Nephrectomy; Rats; Rats, Inbred SHR; Recombinant Proteins; Tacrolimus; Weight Loss

Topics: Animals; Body Weight; Cell Division; Cyclosporine; Hepatectomy; Immunosuppressive Agents; Liver; Liver Regeneration; Male; Rats; Rats, Sprague-Dawley; Sirolimus; Tacrolimus

The present study analyzes pretransplantation variables associated with long-term liver allograft survival in 278 children who underwent transplantation under primary tacrolimus (FK506) therapy at a single center between October 1989 and October 1996.. The influence of 17 pretransplantation variables on long-term liver allograft outcome was analyzed. Donor variables included age, weight, gender, and cold ischemia time. Recipient variables included age, weight, gender, original liver disease, pretransplantation waiting time, previous abdominal surgery, United Network of Organ Sharing (UNOS) status, ABO blood group, bilirubin level, prothrombin time, ammonia level, creatinine level, and reduced-size/split liver grafts.. Overall actuarial graft survival was 79.9% at 1 year, 79.1% at 2 years, and 78.3% at 3, 4, and 5 years. Retransplantation rate was 10.8%. Pretransplantation variables with a significant adverse effect on graft survival by univariate analysis were donor age < or = 1 year (P<0.004), donor weight < or = 10 kg (P<0.003), UNOS status I and II (P<0.007), ABO type O, B, and AB (P<0.03), and reduced-size/split liver grafts (P<0.02). Pretransplantation variables significant by multivariate analysis and therefore independent predictors of inferior graft outcome were donor weight '10 kg (relative risk [RR] 2.91, confidence interval [CI] 1.53-5.51); reduced-size/split liver grafts (RR 2.53, CI 1.30-5.64); and UNOS status I (RR 2.22, CI 1.11-4.43).. Pediatric liver transplant recipients receiving primary tacrolimus therapy have long-term graft survival rates approaching 80%. UNOS status, donor weight, and the use of reduced-size/split liver grafts are the most important factors affecting survival.

Topics: Adolescent; Body Weight; Child; Child, Preschool; Female; Graft Rejection; Humans; Immunosuppressive Agents; Infant; Liver Transplantation; Longitudinal Studies; Male; Multivariate Analysis; Prognosis; Risk Factors; Survival Analysis; Tacrolimus; Tissue Donors; Transplantation, Homologous; Treatment Outcome

Topics: Animals; Body Weight; Fetal Tissue Transplantation; Immunosuppressive Agents; Intestines; Male; Mice; Mice, Inbred C57BL; Rats; Rats, Inbred Lew; Tacrolimus; Transplantation, Heterologous

Cardiac hypertrophy is a fundamental adaptive response to hemodynamic overload; how mechanical load induces cardiac hypertrophy, however, remains elusive. It was recently reported that activation of a calcium-dependent phosphatase, calcineurin, induces cardiac hypertrophy. In the present study, we examined whether calcineurin plays a critical role in pressure overload-induced cardiac hypertrophy.. Pressure overload produced by constriction of the abdominal aorta increased the activity of calcineurin in the rat heart and induced cardiac hypertrophy, including reprogramming of gene expression. Treatment of rats with a calcineurin inhibitor, FK506, inhibited the activation of calcineurin and prevented the pressure overload-induced cardiac hypertrophy and fibrosis without change of hemodynamic parameters. Load-induced expression of immediate-early-response genes and fetal genes was also suppressed by the FK506 treatment.. The present results suggest that the calcineurin signaling pathway plays a pivotal role in load-induced cardiac hypertrophy and may pave the way for a novel pharmacological approach to prevent cardiac hypertrophy.

Topics: Animals; Aorta, Abdominal; Atrial Natriuretic Factor; Blood Volume; Body Weight; Calcineurin; Calcineurin Inhibitors; Cardiomegaly; Constriction, Pathologic; Disease Models, Animal; Echocardiography; Fibrosis; Gene Expression; Genes, Immediate-Early; Heart Rate; Immunosuppressive Agents; Male; Myocardium; Proto-Oncogene Proteins c-fos; Proto-Oncogene Proteins c-jun; Rats; Rats, Wistar; Signal Transduction; Tacrolimus

The objective of this study was to quantitatively characterize the effects FK506 on the pathophysiology observed in a model of chronic granulomatous colitis in rats and compare these effects to those obtained with cyclosporin A (CyA). Chronic granulomatous colitis was induced in female Lewis rats via intramural (subserosal) injections of peptidoglycan/polysaccharide (PG/PS) into the distal colon. Rats then received daily injections (i.m.) of either vehicle for CyA (0.5 ml/kg cremophor), CyA in vehicle (25 mg/kg), saline (0.5 ml/kg) or FK506 (1 mg/kg in saline), beginning 7 days after PG/PS injection and continuing for an additional 2 weeks. On day 21, we found that the intramural injection of PG/PS produced a chronic colitis that was associated with hepatic and splenic granulomatous inflammation. Daily treatment with CyA or FK506 beginning 7 days after the induction of colitis resulted in significant inhibition in colonic mucosal permeability, colonic myeloperoxidase activity and plasma nitrate/nitrite levels when compared with their vehicle or untreated controls. In some instances, we noticed a significant vehicle-dependent anti-inflammatory activity. The incidence of peritoneal adhesions as well as the presence of hepatic and splenic granulomas induced by PG/PS were also significantly reduced in both the CyA- and FK506-treated groups. Taken together, these data suggest that immunosuppressive therapy is effective at attenuating both the colitis as well as the extraintestinal inflammation induced by PG/PS. We conclude that FK506 may be useful in the treatment of certain types of inflammatory bowel disease.

Topics: Animals; Blood Pressure; Body Weight; Colitis; Colon; Cyclosporine; Female; Granulomatous Disease, Chronic; Intestinal Mucosa; Liver; Nitrates; Nitrites; Organ Size; Peptidoglycan; Polysaccharides; Rats; Rats, Inbred Lew; Spleen; Tacrolimus

Leflunomide (Lef) is a novel immunosuppressant that can prevent islet allograft and xenograft rejection. In this study, we investigated the in vivo effects of Lef on the function of normal pancreatic islets and syngeneic islet grafts in rats and compared its effect to cyclosporine (CsA) and FK506. Different groups of rats were treated with Lef (10 and 20 mg/kg/day), CsA (20 mg/kg/day), or FK506 (2 mg/kg/day). After 4 and 6 weeks, nonfasting blood glucose (BG) levels of all the treatment groups were not different from that of the control group. Intravenous glucose tolerance test revealed that the rate of glucose disappearance was normal in Lef-treated groups. However, the rate of glucose disappearance in the CsA- and FK506-treated rats was impaired. In contrast, long-term (7 months) treatment of rats with CsA (10 mg/kg/day) resulted in five of seven rats developing hyperglycemia. However, normal BG was observed in all rats treated for 7 months with Lef (10 mg/kg/day). In the second experimental model, streptozocin-induced diabetic ACI rats were grafted with an average of 1200 syngeneic islets into the liver or kidney capsule. Diabetes in these ACI recipients was stably reversed for 6 months, then these rats were treated with Lef (20 mg/kg/day), CsA (20 mg/kg/day), and FK506 (2 mg/kg/day). After 14 days of treatment, nonfasting BG levels were significantly increased in rats treated with CsA (before: 105 +/- 2.9 mg/ dl, after: 275.8 +/- 60 mg/dl) as well as in rats treated with FK506 (before: 108 +/- 2.4 mg/dl, after: 209 +/- 10.1 mg/dl). In contrast, the BG levels of the Lef-treated rats were indistinguishable from those of the untreated control groups. Site of transplantation, i.e., liver and kidney, did not affect the results. Our results indicating that Lef has no diabetogenic property in vivo lends support to the promise that leflunomide may be effective for clinical islet transplantation.

Topics: Animals; Body Weight; Cyclosporine; Immunosuppressive Agents; Islets of Langerhans; Islets of Langerhans Transplantation; Isoxazoles; Leflunomide; Rats; Tacrolimus; Time Factors

Our laboratory has demonstrated that the immunosuppressants Cyclosporin A (CsA) and tacrolimus (FK506), in vivo in the rat, produce a high-turnover osteopenia. CsA is known to decrease serum testosterone (Test) levels both in the rat and in human transplant patients. Less is known of FK506's effect on androgens. CsA-induced hypogonadism may contribute to the aforementioned bone loss because hypogonadism itself is a risk factor for osteoporosis and fracture. The aim of this study was to assess serum androgen levels following CsA and FK506 therapy and to see wether Test replacement therapy, in the form of 28-day controlled release subcutaneous pellet implants, could prevent CsA-induced osteopenia. Two experiments were conducted. In experiment I, four groups of 6-month-old male Sprague-Dawley rats received the following: (A) CsA vehicle and placebo pellet, (B) Test 15 mg pellet and CsA vehicle, (C) CsA 10 mg/kg and placebo pellet, (D) Test 15 mg pellet and CsA 10 mg/kg. In experiment II, two groups of rats received (E) FK506 vehicle and (F) FK506 4 mg/kg. CsA, FK506, and vehicles were given for 28 days by daily oral gavage. The rats were weighted and bled on days 0, 14, and 28. All rats received double fluorescent labeling, and on day 28 the tibiae were removed for histomorphometry. Whole blood was assayed for CsA and FK506 levels. Serum was assayed for total and free Test as well as for osteocalcin (BGP), blood urea nitrogen (BUN), creatinine, and calcium. Whole blood monoclonal CsA levels measured by fluorescent immunoassay were in the therapeutic range, while a drug concentration profile showed good absorption of FK506. Those rats receiving Test and FK506 lost weight, while those receiving CsA remained constant. BUN was only marginally elevated in the CsA-treated groups on day 28 (p < 0.05), while creatinine was unchanged. On day 28, total and free Test was significantly reduced in the CsA-treated rats versus control (p < 0.05), while Test replacement therapy maintained total Test levels above vehicle (p < 0.01) and free Test levels similar to vehicle on day 28. FK506 did not lower total or free Test levels. BGP levels were significantly increased in the CsA (p < 0.01) and FK506 (p < 0.001) groups on day 28. BGP in the groups receiving Test alone and in combination with CsA remained similar to vehicle. Histomorphometry confirmed CsA- and FK506-induced high-turnover osteopenia. The Test alone group marignally increased bone formation. Test replacement fail

Topics: Animals; Blood Urea Nitrogen; Body Weight; Bone Diseases, Metabolic; Calcium; Creatinine; Cyclosporine; Drug Synergism; Humans; Immunosuppressive Agents; Male; Organ Transplantation; Osteocalcin; Osteoporosis; Rats; Rats, Sprague-Dawley; Tacrolimus; Testosterone

To characterize the dose-related pharmacokinetics of the immunosuppressant agent sirolimus (formerly rapamycin) in kidney transplant patients by use of two-stage and nonlinear mixed-effect model population methods.. Patients (n = 36) from three centers (Germany, the United Kingdom, and Sweden) who received steady-state oral doses of cyclosporine (ciclosporin) were assessed after single oral administration of sirolimus at doses of 3, 5, 10, and 15 mg/m2. Plasma and whole blood sirolimus samples were analyzed by a high-performance liquid chromatographic/mass spectrophotometric method. Simultaneous fitting used biexponential functions with intercept/slope or clearance/volume terms, as well as first-order absorption (ka) and a lag-time.. The nonlinear mixed-effect model method (P-Pharm) provided a better characterization of sirolimus kinetics, especially for the absorption and distribution phases where fewer data were available per patient. Sirolimus distribution between whole blood and plasma was concentration-independent, with a mean blood/plasma ratio (coefficient of variation) of 30.9 (48.5%). Elimination was not influenced by dose, as shown by estimates of the terminal half-life of 63 hours (27.5%) and apparent oral blood clearance of 8.9 L/hr (38.2%). Sirolimus distribution parameters were influenced by body weight and surface area. Sirolimus was rapidly absorbed, as shown by the absorption lag-time of 0.27 hour (35.1%), and ka of 2.77 hr-1 (48.4%). The concomitant administration of sirolimus and cyclosporine did not reveal any pharmacokinetic interactions.. This report provides an initial population pharmacokinetics of sirolimus in kidney transplant recipients receiving cyclosporine concurrently. Sirolimus blood and plasma pharmacokinetics were biexponential and linear for doses from 3 to 15 mg/m2. No pharmacokinetic interaction was found between sirolimus and cyclosporine.

Topics: Adult; Aged; Body Surface Area; Body Weight; Cyclosporine; Female; Half-Life; Humans; Immunosuppressive Agents; Kidney Transplantation; Male; Middle Aged; Models, Statistical; Polyenes; Sirolimus; Tacrolimus

After allogenic transplantations a dramatic increase in the development of arteriosclerotic plaques can be observed, which might be due to metabolic alterations, influenced by changes of the transplant organ or immunosuppression. In this study the effects of FK 506 in kidney transplant patients on cardiovascular risk factors were compared to cyclosporin A (CsA) immunosuppression. Both groups showed no statistical differences in number, kidney function, age, body weight, sex distribution, steroid dosage and follow-up time after transplantation. Total cholesterol was similar in FK 506-treated patients (231 +/- 22 vs. 278 +/- 52 mg/dl) as compared with patients with CsA immunosuppression. Furthermore, there were no differences in triglycerides (220 +/- 72 vs. 210 +/- 67 mg/dl), HDL-cholesterol (67 +/- 14 vs. 52 +/- 18 mg/dl) and fasting glucose (112 +/- 36 vs. 116 +/- 17 mg/dl). However, the concentration of LDL-cholesterol (114 +/- 21 vs. 167 +/- 37 mg/dl), the independent risk factor Lp(a) (11 +/- 9 vs. 27 +/- 8 mg/dl) and fibrinogen (216 +/- 71 vs. 297 +/- 47) was lower in FK 506-treated patients. Our results indicate that FK 506 immunosuppression offers some advantages in cardiovascular risk factors.

Topics: Adult; Age Factors; Arteriosclerosis; Blood Glucose; Body Weight; Cholesterol; Cholesterol, HDL; Cholesterol, LDL; Cyclosporine; Fasting; Female; Fibrinogen; Follow-Up Studies; Glucocorticoids; Humans; Immunosuppressive Agents; Kidney Transplantation; Lipid Metabolism; Lipids; Male; Prednisolone; Risk Factors; Sex Factors; Tacrolimus; Transplantation, Homologous; Triglycerides

The effect of an orally administered glutamine-enriched elemental diet was examined following orthotopic small bowel allotransplantation using Brown Norway rats as donors and Lewis rats as recipients. The recipients was treated with FK 506 and randomized to receive glutamine-free elemental enteral diet solution (glutamine-free group), glutamine-enriched elemental diet solution containing 7500 mg of glutamine per 100 g diet (glutamine-enriched group) or standard chow (chow group) ad libitum for 7 d. There were no histological changes due to resection. Weight loss in the glutamine-enriched group was significantly less than that of the chow group. Both plasma glutamine levels and the ratio of glutamine to total amino acids in the homogenate of the graft mucosa of the glutamine-enriched group were significantly higher than those of the glutamine-fee group. Villous height and crypt depth were significantly decreased in the glutamine-free group. The BrdU labeling index in the graft epithelium and alkaline phosphatase activity in the homogenate of the graft mucosa of the glutamine-enriched group were significantly higher than those of the glutamine-free group. Therefore, orally administered glutamine-enriched elemental diet appears to promote the regeneration and differentiation of the graft mucosa following small bowel allotransplantation.

Topics: Aging; Alanine; Alkaline Phosphatase; Ammonia; Animals; Body Weight; Bromodeoxyuridine; Cell Division; Diet; Epithelial Cells; Glutamic Acid; Glutamine; Immunosuppression Therapy; Immunosuppressive Agents; Intestinal Mucosa; Intestine, Small; Male; Microvilli; Random Allocation; Rats; Rats, Inbred BN; Rats, Inbred Lew; Tacrolimus; Time Factors; Transplantation, Homologous

FK506 (tacrolimus), a potent immunosuppressant, is used for inhibiting allograft rejection in the organ transplantation field. In a preclinical toxicity study in rats, FK506 induced various toxicities, including renal and pancreatic injuries. One of these toxic findings was cataract, and we have found that cataract appeared in rats dosed orally with FK506 for 13 weeks and more. Therefore, to better elucidate the onset mechanism of FK506-induced cataract, we measured biochemical parameters, such as sorbitol, Na,K-ATPase and glutathione in the lens of rats. Rats were dosed with FK506 in oral daily doses of 0.2, 1 or 5 mg/kg for 13 weeks, the lowest dose of which approximated the expected clinical dosage. Cataract developed in the 5-mg/kg/day group, with an incidence of 25%, whereas no cataract formation was observed in the 0.2- or 1-mg/kg/day groups. Five mg/kg/day led an increase of sorbitol and a decrease of reduced type glutathione, but did not affect Na,K-ATPase activity of the lens. FK506 is known to have diabetogenicity mediated through pancreatic injury, which appears as vacuolation of islet cell in rats. Five mg/kg/day of FK506 induced an elevation of blood glucose associated with glucose intolerance, and decrease of both basal insulin level and insulin content in the pancreas, and the changes were in parallel with the cataract development in the present study. On the other hand, diabetic parameters did not change in the 0.2- or 1-mg/kg/day groups. These observation suggest that diabetes developed in the rats dosed with 5 mg/kg/day of FK506. Coadministration of a novel aldose reductase inhibitor, Zenarestat, at an oral dose of 50 mg/kg/day resulted in a reduction of incidence of the FK506-induced cataract and a decrease of sorbitol levels in the lens when compared to that in the lens of rats dosed with 5 mg/kg/day of FK506. These results suggest that FK506-induced cataract in rats is due to an accumulation of sorbitol in the lens, secondary to the diabetogenic effect of FK506. FK506 treatment at the doses of 0.2 and 1 mg/kg/day neither affected parameters indicative of diabetes nor induced cataract in rats, suggesting that the cataract would not develop with FK506 if diabetic parameters were kept under control.

Topics: Administration, Oral; Aldehyde Reductase; Animals; Blood Glucose; Body Weight; Cataract; Diabetes Mellitus, Experimental; Enzyme Inhibitors; Glucose Tolerance Test; Glutathione; Immunosuppressive Agents; Insulin; Lens, Crystalline; Male; Quinazolines; Rats; Sodium-Potassium-Exchanging ATPase; Sorbitol; Tacrolimus

The development of atherosclerotic cardiovascular complications is a common and serious problem for the long-term survivors of organ transplantation. Cyclosporine A plus steroid-based immuno-suppression regimens in these patients are associated with the development of hypertension, hyperlipidemia, obesity, and diabetes mellitus. Whether the new immunosuppressive agent tacrolimus (FK506) confers any advantage in terms of these cardiovascular risk factors has been less well studied. We compared serial changes in blood pressure, lipids, body weight, and glucose levels during the first 12 months after liver transplantation in patients using either cyclosporine A (n = 39) or tacrolimus (n = 24)-based immunosuppression. By 12 months, the prevalence of hypertension, hypercholesterolemia, and obesity was increased in the cyclosporine A group compared to tacrolimus: 82% versus 33%, 33% versus 0%, and 46% versus 29%, respectively (all p < .05). Triglyceride and total cholesterol levels were 196 +/- 23 versus 125 +/- 13 mg/dL and 225 +/- 9 versus 159 +/- 7 mg/dL for the cyclosporine A versus tacrolimus groups, respectively (p < .05). Cumulative posttransplant steroid dose was not related to the observed lipid changes in either group, although the increase in triglycerides was positively correlated to weight gain and diuretic use in the cyclosporine A group. The incidence of diabetes mellitus was not increased from baseline in either group. These results indicate that tacrolimus, compared to cyclosporine A, is associated with a less adverse cardiovascular risk profile in the first year after liver transplantation. Whether these differences persist and become clinically relevant to a liver transplant recipient population that is increasingly older and has more preexisting cardiovascular disease remains to be determined.

Topics: Adult; Benzothiadiazines; Blood Glucose; Blood Pressure; Body Weight; Cyclosporine; Diabetes Mellitus; Diuretics; Female; Humans; Hypercholesterolemia; Hypertension; Hypertriglyceridemia; Lipids; Liver Transplantation; Male; Middle Aged; Obesity; Prednisone; Risk Factors; Sex Factors; Sodium Chloride Symporter Inhibitors; Tacrolimus

Tacrolimus (FK506) is at present the mainstay of immunosuppression for small intestinal transplantation. This study investigates the effects of chronic treatment with varying dosages of tacrolimus on animal well-being, weight gain, intestinal permeability, and the active transport of nutrients as measured by in vitro studies quantifying glucose flux. The effect of acute treatment with high-dose tacrolimus on glucose flux was also investigated. In the chronic studies, juvenile male Lewis rats were given tacrolimus in a dosage of 0.1 mg/kg, 0.5 mg/kg, and 2 mg/kg q. second day by subcutaneous injection for five weeks. In the acute studies, animals were treated with 2 mg/kg given q. 24 hr [mult] 48 hr, 24 hr and 12 hr prior to sacrifice. In the acute treatment groups, tacrolimus caused no change in glucose flux. In the chronically treated animals, FK506 levels were within the clinically relevant range. Chronic treatment with 0.5 and 2 mg/kg caused a significant reduction in weight gain. These same groups of animals had a significant increase in intestinal permeability as measured by absorption of 99Te-DTPA. Glucose flux was affected in all chronically treated groups, with net flux increasing in the jejunum and decreasing in the ileum. These findings show that chronic treatment with low-dose tacrolimus is well tolerated, but in higher doses there are significant effects in intestinal permeability and nutrient uptake, and animal weight gain. We suggest that these changes are due to alterations in intestinal permeability that do not appear to be mediated by an acute drug effect and more likely represent chronic changes, possibly from alterations in gene expression. These findings suggest that further studies regarding the effects of tacrolimus on nutrient transport, intestinal permeability, and the known immunologically related functions of tacrolimus should be done.

Topics: Animals; Body Weight; Cell Membrane Permeability; Dose-Response Relationship, Drug; Drug Administration Schedule; Eating; Glucose; Immunosuppressive Agents; Intestinal Absorption; Male; Monosaccharide Transport Proteins; Rats; Rats, Inbred Lew; Tacrolimus

Topics: Alanine Transaminase; Animals; Aspartate Aminotransferases; Blood Glucose; Blood Urea Nitrogen; Body Weight; Creatinine; Hepatocyte Growth Factor; Humans; Immunosuppressive Agents; Kidney; Male; Rats; Rats, Inbred SHR; Recombinant Proteins; Tacrolimus

The effect of splenectomy on allograft survival was investigated using orthotopic liver transplantation in a rat experimental model (ACI rat liver grafted to LEW rat). Control rats without any immunosuppressive treatment died, on average, 10.4 +/- 1.4 days after operation. Splenectomy alone somewhat prolonged the survival (13.4 +/- 2.0 days), and low-dose FK506 therapy moderately prolonged it (22.7 +/- 7 days). The graft survival period was significantly prolonged (39.7 +/- 6.3 days) when them two treatments were combined. The elevation of cytotoxic antiallograft antibodies was suppressed by splenectomy but not by low-dose FK506 therapy. The development of jaundice was moderately suppressed by FK506 but not by splenectomy. There was no difference between the pattern of body weight decline in either of them two groups and that in control rats. When these two treatments were combined at the same time, the elevation of cytotoxic antibodies, development of jaundice and decline of body weight were suppressed. These data indicate that B cells play an important role in the acute rejection of the rat liver allograft at least partially via production of cytotoxic antiallograft antibody. Splenectomy or other immunosuppressive methods affecting B cells can be a supplement for immunosuppression when using reduced-dose FK506.

Topics: Animals; B-Lymphocytes; Body Weight; Cytotoxicity, Immunologic; Dose-Response Relationship, Drug; Graft Survival; Immunosuppression Therapy; Isoantibodies; Liver Transplantation; Male; Rats; Rats, Inbred ACI; Rats, Inbred Lew; Splenectomy; Tacrolimus

Prograf (FK506) was given to male mature rats in a daily subcutaneous dose of 1 or 3 mg/kg/day for 2 weeks to investigate its effect on spermatogenesis. Prograf dose-dependently sperm counts and motility, but did not affect testosterone level in the serum of rats. Histopathologically, there were no abnormal changes in the testis, seminal vesicle or prostate in any rats dosed with Prograf, but intra-ductal eosinophilic globules, probably degeneration of the sperm cells, were observed in the epididymis of the 3 mg/kg/day group. Sperm counts and motility returned to the control levels after stopping of the drug. The results indicate that Prograf decreased sperm counts and motility through direct action on the sperm in the epididymis, but not the production of sperm in the testis. Cyclosporine A (CsA) was used as the reference drug in the present study. Thirty mg/kg/day of CsA also decreased sperm counts and motility, and stopping of the drug led to the recovery of these changes. The males dosed with Prograf for 2 weeks were mated with non-dosed females to investigate its effect on the fertility potential of the males. Prograf did not affect copulation or fertility index, but a decrease in the number of live fetuses associated with implantation loss was observed in the 3 mg/kg/day group. The changes were considered to be due to the decrease of sperm counts and motility, although 1 mg/kg/day of Prograf, 5-10 times the clinical dose, did not affect any fertility parameters including implantation index.

Topics: Animals; Body Weight; Cyclosporine; Epididymis; Female; Fertility; Follicle Stimulating Hormone; Immunosuppressive Agents; Luteinizing Hormone; Male; Organ Size; Prostate; Rats; Reproduction; Seminal Vesicles; Sperm Count; Sperm Motility; Spermatogenesis; Tacrolimus; Testis; Testosterone

Topics: Analysis of Variance; Animals; Antibodies, Monoclonal; Body Weight; Combined Modality Therapy; Diabetes Mellitus, Experimental; Duodenum; Graft Survival; Immunosuppression Therapy; Immunosuppressive Agents; Intercellular Adhesion Molecule-1; Lymphocyte Function-Associated Antigen-1; Male; Pancreas Transplantation; Rats; Rats, Inbred F344; Rats, Inbred Strains; Tacrolimus; Time Factors; Transplantation, Homologous; Urination

Clinically, FK506 is superior to CsA after solitary small bowel transplantation (SBTx). Development of diarrhea after SBTx has been the rationale for adding the colon to small bowel grafts. However, the additional lymphoid and bacterial content transferred with total small plus large bowel transplants (TBTx) might aggravate the alloimmune response-rejection and graft-versus-host disease (GVHD)-and increase the risk of infection. We studied the incidence of rejection, GVHD, and infection after TBTx and the impact of CsA versus FK506. We performed orthotopic TBTx with portal drainage after total enterectomy in outbred Yorkshire Landrace pigs, divided into 3 groups: control pigs (n=6) received no immunosuppression; CsA pigs (n= 14) received CsA (5 mg/kg), antilymphocyte globulin (10 mg/kg for 10 days), prednisone (2 mg/kg), and AZA (2.5 mgtkg); and FK506 pigs (n=9) received FK506 (0.2 mg/kg) and prednisone (2 mg/kg). Trough CsA whole blood levels were >400 ng/ml for the first 7 days and >200 ng/ml thereafter. FK506 levels were > 15 ng/ml. We excluded from further analysis 5 early deaths (<3 days) due to anesthesiologic (n=2) or technical reasons (n=3). Median survival of control pigs was 9.5 days (range, 4-13). Cyclosporine did not extend survival: median, 9 days (range, 5-31) (P=0.6). FK506 prolonged survival: median, 37 days (range, 21-49) (P<0.001 vs. control and CsA pigs). Of FK506 pigs, 60% gained weight (+75 g/day), whereas 100% of controls and 75% of CsA pigs lost weight (-550 g/day and -300 g/day, respectively). All control pigs died of rejection within 2 weeks versus none of the FK506 pigs. However, 36% of CsA pigs died of rejection. Groupwise comparison showed less rejection in FK506 versus control pigs (P<0.001) and in FK506 versus CsA pigs (P<0.03), but no difference between CsA and control pigs. None of the control pigs died of GVHD versus 18% of CsA pigs (by day 31) and 37% of FK506 pigs (by day 49). Groupwise comparison showed increased GVHD in FK506 versus control pigs (P<0.001) and a tendency toward increased GVHD in FK506 versus CsA pigs (P=0.08). None of the control pigs died of infection alone versus 22% of CsA pigs (by day 31) and 67% of FK506 pigs (by day 49). Groupwise comparison showed increased infection in FK506 versus control pigs (P<0.001). We detected significant endotoxemia early and late postoperatively. But we saw no specific correlation between endotoxemia, rejection, GVHD, or infection. Based on this study, we have drawn sev

Topics: Animals; Body Weight; Cyclosporine; Endotoxins; Graft Rejection; Graft vs Host Disease; Immunosuppressive Agents; Infections; Intestine, Large; Intestine, Small; Prospective Studies; Swine; Tacrolimus; Toxemia

The effects of low dose FK506 therapy (0.1 mg/ kg/day x 1 day) on graft survivals were analyzed, and the feasibility of splenectomy was assessed. ACI strain liver grafts were orthotopically implanted into LEW male rat recipients. In the control group, the survival period was 10.4 +/- 1.4 days. In the group treated with splenectomy, the survival period was 13.4 +/- 2.0 days. In the groups with low dose FK506 therapy, the survival periods were 22.7 +/- 6.7 and 39.7 +/- 6.3 days with or without splenectomy, respectively. Rats in the group with average dose FK506 (1.0 mg/kg/day x 7 days) survived more than 100 days. In summary, the effect of low dose FK506 therapy was relatively limited. Splenectomy by itself was marginally effective; however, this effect was enhanced when combined with low dose FK506 therapy.

Topics: Animals; Body Weight; Dose-Response Relationship, Drug; Graft Rejection; Graft Survival; Immunosuppressive Agents; Jaundice; Liver Transplantation; Male; Postoperative Complications; Rats; Splenectomy; Tacrolimus

We examined whether an immunosuppressant, FK506, inhibits delayed neuronal death in the gerbil hippocampal CA1 sector after 5-min forebrain ischemia. After reperfusion, gerbils were injected intravenously with FK506. Gerbils in the early injection group were injected with FK506 immediately after reperfusion, and gerbils in the delayed injection group were injected with FK506 1 or 2 h postischemia. The body temperature of the FK506-treated gerbils in the normothermic group was maintained at 37.5-38.0 degrees C for 2 h postischemia. In the chronic survival group, neuroprotection was assessed after recovery for 45 days. Seven or 45 days after reperfusion, neuronal density in the CA1 was assessed following perfusion fixation. FK506 ameliorated cell death in the CA1 in a dose-dependent manner in every group, although it showed a hypothermic effect. FK506 is neuroprotective against forebrain ischemia in gerbils.

Topics: Animals; Body Weight; Cell Death; Dose-Response Relationship, Drug; Gerbillinae; Hippocampus; Hypothermia; Immunosuppressive Agents; Male; Neurons; Neuroprotective Agents; Prosencephalon; Reperfusion Injury; Tacrolimus; Time Factors

Topics: Alanine Transaminase; Alkaline Phosphatase; Animals; Blood Proteins; Blood Urea Nitrogen; Body Weight; Drinking Behavior; Feeding Behavior; Hepatectomy; Kidney Function Tests; Liver; Liver Function Tests; Liver Regeneration; Organ Size; Rats; Rats, Wistar; Tacrolimus; Thymectomy

Recent studies in liver and kidney transplant recipients revealed a nephrotoxic adverse effect of the new macrolide immunosuppressant FK-506. Therefore the effect of FK-506 0.1 to 0.8 mg per kg per day was investigated in rats using clearance methods including lithium clearance. In rats given FK-506 or placebo during 1 week the nephrotoxicity of FK-506 was characterized by a slight reduction of inulin clearance. The end proximal delivery as measured by the lithium clearance was decreased by FK-506. In rats treated for 4 weeks with FK-506 0.8 mg/kg/day the glomerular filtration rate (GFR) had decreased to 23% of the GFR found in controls (P < 0.001), while end proximal delivery was only 8% of normal. Renal histopathological investigation showed a slight but statistically significant increase of tubular basophilia and atrophy in FK-506-treated rats. Skin transplantation studies in the same rat strain showed a dose-dependent immunosuppressive effect of FK-506. FK-506 0.8 mg/kg was significantly more immunosuppressive than 0.2 or 0.4 mg/kg, so it was concluded that the lower doses of FK-506 did not fully exploit the drug's immunosuppressive potential. Thus in a dosage inside the therapeutic range defined from skin transplantations, FK-506 generated a number of toxic effects including a considerable nephrotoxic effect. The FK-506 induced changes in glomerular and tubular function was a close match to the changes found in cyclosporin A nephrotoxicity. The present study suggests that FK-506 nephrotoxicity is caused by constriction of preglomerular vessels.

Topics: Animals; Body Weight; Dose-Response Relationship, Drug; Drinking; Eating; Glomerular Filtration Rate; Graft Rejection; Inulin; Kidney; Kidney Glomerulus; Kidney Tubules, Proximal; Lithium; Male; Metabolic Clearance Rate; Rats; Rats, Inbred Lew; Rats, Sprague-Dawley; Skin Transplantation; Tacrolimus; Urination

The effects of interferon-alpha A/D (IFN) therapy in combination with various immunosuppressants were investigated in a murine model of viral myocarditis. Viral infection is an important cause of morbidity in immunocompromised hosts and transplant recipients. Human IFN therapy reduces viral replication, reducing the virus-induced myocardial destruction. Groups consisting of 25 C3H/He mice received i.p. injections of prednisolone, azathioprine, 15-deoxyspergualin, cyclosporine or tacrolimus (FK506), for 16 days beginning 2 days before inoculation with 500 plaque-forming units of encephalomyocarditis virus (EMCV). IFN, 10(4) U/g daily, was administered i.p. alone or in combination with immunosuppressants to separate groups of mice beginning on the day of viral inoculation. Animals were sacrificed at random at 4 or 10 days after inoculation with EMCV. The survival rate was significantly higher in mice treated with azathioprine, 15-deoxyspergualin, cyclosporine or FK506 in combination with IFN than in infected controls (P < .01) and was similar to the rate in the IFN monotherapy group. Survival in mice treated with prednisolone resembled that in infected controls and was significantly lower than in mice treated with IFN (P < .01). Heart weight was lower and cellular infiltration in the myocardium was reduced in mice treated with both FK506 and IFN compared with mice given IFN monotherapy. The results suggest that the effect of IFN therapy in viral myocarditis differs depending on which immunosuppressants is used. The findings suggest that the combination of FK506 and IFN may have beneficial effects in hosts with viral myocarditis by reducing cellular infiltration of heart.

Topics: Animals; Antiviral Agents; Body Weight; Cardiovirus Infections; Drug Synergism; Encephalomyocarditis virus; Female; Humans; Interferon Type I; Interferon-alpha; Mice; Mice, Inbred C3H; Myocarditis; Myocardium; Organ Size; Recombinant Fusion Proteins; Recombinant Proteins; Tacrolimus

1. FK 506 (Tacrolimus, Prograf) is a novel immunosuppressant which is effective in solid organ transplantation and autoimmune diseases. The lack of a suitable animal model has hindered the study of the nephrotoxicity of the drug which has emerged as a common adverse effect in clinical trials. We report both acute and chronic nephrotoxicity with tacrolimus (FK) in which renal structure and function are worsened by sodium depletion. 2. Pair fed male Sprague-Dawley rats were given FK (3 or 6 mg/kg, p.o.) or vehicle for 7, 21 and 42 days on low salt or normal diet. The FK whole blood trough levels achieved (3-10 ng/mL) were similar to those observed in FK treated transplant patients. 3. In salt depleted animals treated for 7 days, FK (6 mg/kg) decreased renal blood flow and glomerular filtration rate (1.8 +/- 0.1 and 0.2 +/- 0.1 mL/min per 100 g vs 2.9 +/- 0.2 and 1.1 +/- 0.1 mL/min per 100 g in the vehicle group, P < 0.01). 4. After 21 days of treatment of FK on low salt diet but not normal salt, FK induced focal collapse and vacuolization in proximal tubules and discrete or confluent zones of tubulointerstitial oedema and mononuclear cell infiltration. 5. After 42 days in salt depleted rats, there was significant tubulointerstitial scarring that was associated with an increased plasma renin activity (PRA) (64 +/- 10 vs 30 +/- 4 ng AI/mL per h in the vehicle group, P < 0.05). Animals given normal salt diets did not develop significant histological lesions even up to 42 days.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Animals; Body Weight; Creatinine; Glomerular Filtration Rate; Immunosuppressive Agents; Inulin; Kidney Diseases; Kidney Function Tests; Magnesium Deficiency; Male; Organ Size; Rats; Rats, Sprague-Dawley; Renal Circulation; Renin; Sodium; Tacrolimus; Urodynamics

Topics: Amylases; Animals; Blood Glucose; Body Weight; Cricetinae; Diabetes Mellitus, Experimental; Graft Rejection; Immunosuppression Therapy; Male; Mesocricetus; Pancreas; Pancreas Transplantation; Rats; Rats, Inbred Lew; Splenectomy; Tacrolimus; Transplantation, Heterologous

Administration of cyclosporine A to male and female rats accelerates bone remodeling and causes bone loss, among other side-effects. The newer immunosuppressant drugs, FK506 and CsG, have been synthesized to counteract the toxic effects of CsA, yet maintain clinical efficacy. We investigated the in vivo effects of long-term administration of these drugs on bone mineral metabolism in the rat. Five groups of Sprague-Dawley rats, 15 per group, were allocated to receive by daily gavage for a period of 28 days: (1) Cs-vehicle; (2) CsA 15 mg/kg b.w.; (3) CsG 15 mg/kg b.w.; (4) FK506 vehicle; (5) FK506 5 mg/kg b.w. Blood was sampled on days 0, 14, and 28 for measurement of ionized calcium (Ca2+), parathyroid hormone (PTH), 1,25-(OH)2-vitamin D, and bone gla protein (BGP). Tibiae were removed on day 28 after double calcein labeling for histomorphometric analysis. Immunosuppressant groups were compared with the respective vehicle groups. Neither CsA or CsG affected the levels of Ca2+ or PTH, whereas by day 28 FK506 caused a decrease in Ca2+ and a corresponding rise in PTH (P < 0.05). The 1,25-(OH)2-vitamin D and BGP levels in both the CsA and CsG groups were increased on days 14 and 28 (P < 0.05), while FK506 had no effect on these serum levels. Tibial bone histomorphometry revealed that all 3 immunosuppressants increased measures of bone formation and bone resorption, accompanied by a significant reduction in percent trabecular area, most marked with FK506. This report demonstrates that all three immunosuppressants have adverse effects on bone--most deleterious with FK506.

Topics: Animals; Body Weight; Bone Resorption; Calcification, Physiologic; Calcitriol; Cyclosporine; Cyclosporins; Female; Immunosuppressive Agents; Male; Osteocalcin; Osteogenesis; Rats; Rats, Sprague-Dawley; Tacrolimus; Tibia; Time Factors

Vascularized whole pancreas transplantation in the rat was performed on the abdomen using a cuff technique for vascular anastomoses. Two different exocrine drainage procedures, either intestinal or ureter drainage, were used. In the isograft transplant models, hyperglycemia was ameliorated immediately after transplantation and all of the grafts functioned during the observation period. In the allograft transplant models without immunosuppression, graft rejection, as defined by recurrence of hyperglycemia (blood glucose > 200 mg/dl) occurred 6-9 days post-transplant. Allograft rejection could be delayed approximately 1 month after transplant with short-term use of FK506. These different models, using either intestinal or ureter exocrine drainage, are similar to dominant clinical pancreas transplantation with enteric exocrine drainage or urinary tract drainage, respectively. It is thus concluded that whole pancreas transplant with either intestinal or ureter exocrine drainage is an ideal model for physiological and immunological experimental studies in pancreas transplantation.

Topics: Animals; Blood Glucose; Body Weight; Diabetes Mellitus, Experimental; Drainage; Graft Rejection; Graft Survival; Male; Pancreas Transplantation; Rats; Rats, Inbred Lew; Tacrolimus

Topics: Animals; Body Weight; Cytotoxicity, Immunologic; Drug Therapy, Combination; Graft Survival; Graft vs Host Reaction; Prednisolone; Rats; Rats, Inbred Lew; Rats, Inbred Strains; Skin; Spleen; Tacrolimus; Time Factors; Transplantation, Homologous; Transplantation, Isogeneic

We investigated the effects of FK506 and glucocorticoids (GC) on rat thymocytes using flow cytofluorometry. Rats were treated with GC (0.1 mg/body, by single injection), with FK506 (1 mg/kg/day, for 7 days), or with FK506 and GC. GC alone significantly decreased the percentage of CD4+8+ thymocytes and increased the percentages of CD4-8-, CD4+8- and CD4-8+ thymocytes on day 7. FK decreased the percentage of CD4+8- and CD4-8+ thymocytes and increased the percentage of CD4+8+ thymocytes on days 5 to 14. FK and GC induced a significant decrease in the number of CD4+8+ thymocytes greater than that seen with GC alone on day 7. The absolute number of TCR alpha beta high MHC class Ihigh thymocytes after FK and GC was significantly lower than that of the control group, and was slightly lower than that after FK alone on day 14. These results suggest that combined treatment with FK506 and GC acts complexly to decrease rat CD4+8+ thymocytes and prevents thymocyte differentiation and maturation.

Topics: Animals; Body Weight; CD4-Positive T-Lymphocytes; CD8-Positive T-Lymphocytes; Cell Differentiation; Dexamethasone; Flow Cytometry; Histocompatibility Antigens Class I; Immunosuppressive Agents; Male; Rats; Rats, Inbred Lew; Receptors, Antigen, T-Cell, alpha-beta; T-Lymphocyte Subsets; Tacrolimus; Thymus Gland

Rejection is still the limiting factor for successful organ transplantation, and overdosage of immunosuppressive drugs often results in severe viral infection, side-effects and toxicity. Thus, more specific immunosuppression to lessen these side-effects is highly desirable. In this study, we compared the effects of FK 506 administered by different routes (hepatic artery, portal vein and systemic circulation) on the inhibition of rejection. FK 506 was given to recipient LEW rats with PVG liver grafts via the penile vein (systemic administration), portal vein or hepatic artery (local administration) for 3 or 7 successive days after liver transplantation. In control LEW rats without immunosuppression, the PVG liver allografts were rejected between 9 and 21 days after transplantation. Intravenous administration of FK 506 for 3 days (0.32 and 1.28 mg/kg daily) only had a marginal effect on prolonging liver allograft survival (21.1 +/- 12.5 and 32.0 +/- 24.0 days, respectively; control 14.1 +/- 4.1 days). However, systemic administration of FK 506 (0.08-1.28 mg/kg daily) for 7 days suppressed liver allograft rejection markedly (42.3 +/- 5.9 to 80.5 +/- 53.4 days; control 14.1 +/- 4.1 days), and 50% of the recipient rats survived for at least 60 days after liver transplantation. Moreover, when a low dose of FK 506 (0.32 mg/kg) was infused into the hepatic artery or portal vein of the transplanted liver for 3 days only, liver allograft survival times were prolonged markedly, and 54% of rats with grafts survived for at least 60 days. This effect was almost equal to that after 7 days systemic treatment with FK 506. In conclusion, 7 days' treatment with FK 506 administered systemically was an effective regimen for the suppression of liver allograft rejection in rats. Furthermore, local immunosuppression with low-dose, short-term (3 days) FK 506 treatment administered via the hepatic artery or portal vein of the transplanted liver dramatically improved allograft salvage.

Topics: Animals; Aspartate Aminotransferases; Bilirubin; Body Weight; Graft Survival; Hepatic Artery; Infusions, Intra-Arterial; Infusions, Intravenous; Liver Transplantation; Male; Portal Vein; Rats; Rats, Inbred Lew; Rats, Inbred Strains; Survival Rate; Tacrolimus; Time Factors; Transplantation, Homologous

We assessed the immunomodulatory effect of leflunomide (LEF) in a heterotopic abdominal model of rat heart transplantation using a major histocompatibility mismatch (DA X LEW). The endpoint of this study was cardiac rejection assessed by abdominal palpation of the ventricular impulse and confirmed by laparotomy and histology. In this study, LF was investigated using four dosages (5, 10, 20 and 30 mg/kg per day orally) against cyclosporine (CsA) (15 mg/kg per day orally) and FK 506 (1 mg/kg per day orally). The ability of LEF to prevent rejection and reverse ongoing acute rejection was assessed. The results showed that untreated hearts were fully rejected by day 5 and that LEF at 5 mg/kg was significantly better than any other dose tested, was superior to FK 1 mg/kg, and was as effective as CsA 15 mg/kg in preventing rejection after a short course of treatment. After a longer course, 10 and 20 mg/kg LEF proved more effective than 5 mg/kg in controlling rejection and as efficacious as 1 mg/kg FK and 15 mg/kg CsA. In the control of ongoing established early rejection. LEF proved to be equally effective, even at lower doses (5 mg/kg), to CsA 15 mg/kg and FK 1 mg/kg. In the control of ongoing established late rejection, 20 mg/kg LEF proved to be superior to 10 mg/kg LEF and 15 mg/kg CsA, and was as effective as FK 1 mg/kg. However, when higher doses of CsA (25 mg/kg) and FK (2 mg/kg) were tested against 20 mg/kg LEF in this mode of rescue, LEF proved as effective as CsA and superior to FK. In the assessment of drug toxicity using body weight as a parameter, 20 mg/kg LEF proved safer than any other LEF dose tested, and safer than 15 mg/kg CsA and 1 mg/kg FK in both short- and long term administration. We conclude that LEF is a relatively safe and potent immunosuppressant with promising clinical potential.

Topics: Animals; Body Weight; Cyclosporine; Graft Rejection; Graft Survival; Heart Transplantation; Immunosuppressive Agents; Isoxazoles; Leflunomide; Male; Rats; Rats, Inbred Lew; Rats, Inbred Strains; Tacrolimus; Time Factors; Transplantation, Homologous

Preventive effects of FK506 on autoimmune myocarditis have been demonstrated, but the therapeutic efficacy of the agent in established myocarditis yet remains to be assessed. In this study, effects of FK506 on experimental autoimmune myocarditis were investigated by the use of the agent after the onset of the disease. Lewis rats were immunized with either cardiac myosin or bovine serum albumin (BSA) in complete Freund's adjuvant. The onset of the disease was ascertained by examining randomly chosen cardiac myosin-immunized rats. Animals were divided into four groups: the BSA-immunized saline-treated group (group A, n = 6); the BSA-immunized FK506-treated group (group B, n = 6); the myosin-immunized saline-treated group (group C, n = 6); and the myosin-immunized FK506-treated group (group D, n = 11). Saline or 1.0 mg/kg/day of FK506 were intramuscularly injected from day 16 to day 27. All the rats were put to death on day 28. Rats of group C became severely ill by the third week, while in contrast, rats of group D remained active, as did rats of groups A and B. The heart weight/body weight ratio was significantly lower in group D than in group C rats. Group mean values were 3.48 +/- 0.10 gm/kg for group A, 3.48 +/- 0.16 gm/kg for group B, 4.94 +/- 0.66 gm/kg for group C, and 3.88 +/- 0.43 gm/kg for group D. Rats of group C showed severe myocarditis with mononuclear cell infiltration, myocardial necrosis, and interstitial edema.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Animals; Autoimmune Diseases; Body Weight; Heart; Myocarditis; Myocardium; Organ Size; Random Allocation; Rats; Rats, Inbred Lew; Tacrolimus

In LEW rats treated daily with variable doses of FK506 for 14 days and weekly thereafter, successful intestinal transplantation from fully allogeneic BN donors never was complicated by fatal GVHD. In contrast, with LEW-to-BN transplantation, rejection was difficult to control and GVHD developed after the end of the daily treatment. However, FK506 in high daily doses continued after the initial 14-day course could prevent this GVHD or even reverse it after allowing its onset. Further experiments did not clarify why the BN rat was an "easy" donor and "difficult" recipient. In unaltered animals the lymphocyte population of normal LEW rats had a higher proportion of T cells, fewer B cells, and a lower CD4:CD8 ratio than normal BN rats. However, one-way MLR reactions of the BN and LEW combinations were generally similar in either direction and not affected differently by the addition of FK506 to the medium. The two-way lymphocyte traffic from graft to host lymphoid organs and vice versa also was similar with BN-to-LEW and LEW-to-BN models. The BN rat may be a useful tool to investigate inadequately explained mechanisms of GVHD.

Topics: Animals; Body Weight; Drug Administration Schedule; Graft vs Host Disease; Intestine, Small; Lymphocyte Subsets; Male; Rats; Rats, Inbred Lew; Remission Induction; Species Specificity; Tacrolimus; Time Factors; Transplantation Immunology

The pancreas has been reported as a possible target for FK506 toxicity. This study was conducted to examine the effects of FK506 on the structure and function of pancreatic acinar cells.. Male Sprague-Dawley rats received an intramuscular injection of saline or FK506, and pancreatic acini were isolated on the day of sacrifice.. FK506 caused a time-dependent suppression in amylase secretory response to cholecystokinin or carbachol at days 3-14, and increases in amylase and trypsinogen content at days 7-14. The properties of cholecystokinin and scopolamine binding sites in acini were not altered by FK506. Amylase release by A23187 and secretin were decreased by FK506, but those by phorbol ester 12-O-tetradecanoylphorbol-13-acetate, forskolin, 5'-cyclic adenosine monophosphate and vasoactive intestinal peptide were not changed. Increases in cytosolic free calcium concentration induced by cholecystokinin were not changed by FK506. Histologically, a significant increase in cytoplasmic zymogen granules was observed in pancreas from FK506-treated rats.. These data suggest that FK506 induced changes in function and metabolism in pancreatic acinar cells, and these changes might be caused by altering postreceptor loci in stimulus-secretion coupling.

Topics: Amylases; Analysis of Variance; Animals; Atropine; Body Weight; Calcimycin; Calcium; Carbachol; Cholecystokinin; Colforsin; Cytosol; Dose-Response Relationship, Drug; Feeding Behavior; Kinetics; Male; N-Methylscopolamine; Pancreas; Rats; Rats, Sprague-Dawley; Receptors, Cholecystokinin; Reference Values; Scopolamine; Scopolamine Derivatives; Secretin; Sincalide; Tacrolimus; Tetradecanoylphorbol Acetate; Time Factors; Trypsinogen; Vasoactive Intestinal Peptide

The immunosuppressive effect of FK506 (FK) in comparison to cyclosporine A (CsA) on lung graft rejection was demonstrated using 24 mongrel dogs with left lung allotransplantation. The cytotoxic activity of peripheral blood mononuclear cells was evaluated using donor skin fibroblasts. In eight dogs not given immunosuppression, the grafted lungs lost aeration 5-10 days postoperatively, and histologic findings revealed grade II rejection and cytotoxic activity elevated to between 10.7 and 60.5%, being an average of 31.2% at an effector/target (E/T) ratio of 50. Of 12 dogs treated with FK, none demonstrated a cytotoxic activity of 10% or more at an E/T ratio of 50. Moreover, histologic examinations of the specimens obtained by open chest biopsy revealed no signs of rejection during the first 10 postoperative days of FK administration, except in one dog showing grade I rejection from the FK 0.05 mg/kg group. A dose study of the duration until the onset of graft rejection and the elevation of cytotoxic activity after the termination of FK administration revealed approximately 1-2 weeks in the FK 0.05 mg/kg group, 3-4 weeks in the 0.1 mg/kg group, and later in the 0.4 mg/kg and 2.0 mg/kg groups. However, severe body weight loss was seen in the 0.4 mg/kg and 2.0 mg/kg groups postoperatively, without recovery even after the termination of FK. In fact, two dogs died of pneumonia possibly derived from general emaciation. These results suggest the optimal concentration of FK in canine lung allo-transplantation to be 0.1 mg/kg intramuscularly.

Topics: Animals; Body Weight; Cyclosporine; Cytotoxicity, Immunologic; Dogs; Dose-Response Relationship, Immunologic; Fibroblasts; Graft Rejection; Immunosuppression Therapy; Leukocytes, Mononuclear; Lung; Lung Transplantation; Models, Biological; Skin; Tacrolimus

In this report, we describe the effect of FK506 on glucose-mediated insulin release in normal dogs. Dogs were placed into one of two groups, group 1 dogs received FK506 (1 mg/kg/d orally) for 2 weeks, and group 2 dogs received FK506 at the same dose, but for 4 weeks. Following the treatment period, both groups of dogs were allowed a recovery period during which time no FK506 was administered. Intravenous glucose tolerance tests (IVGTT) were performed (0.5 mg/kg IV) before FK506 treatment, after 2 or 4 weeks of treatment, and following the recovery periods. Complete blood cell counts (CBC) and serum chemistries were also obtained at these times. Following FK506 treatment for either 2 or 4 weeks, the dogs experienced a delay in glucose disappearance in response to IV glucose injection. Insulin secretion during IVGTT was unchanged in dogs treated for only 2 weeks, but was significantly decreased in dogs treated for 4 weeks. Following the recovery period, glucose disappearance during IVGTT returned to normal in dogs that were treated for 2 weeks, and was more rapid than normal in dogs that had been treated for 4 weeks. Insulin secretion after the recovery period remained unchanged in group 1 dogs, but continued to be significantly reduced in group 2 dogs that had received FK506 for 4 weeks. No significant change was detected in the CBCs or serum chemistries.

Topics: Animals; Blood Glucose; Body Weight; Dogs; Female; Glucose Tolerance Test; Insulin; Insulin Secretion; Male; Tacrolimus

Topics: Analysis of Variance; Animals; Body Weight; Interleukin-1; Interleukin-2; Kinetics; Liver; Liver Function Tests; Liver Regeneration; Male; Organ Size; Rats; Rats, Inbred Strains; Recombinant Proteins; Reference Values; Tacrolimus

A new immunosuppressive compound, FK-506, is a macrolide produced by Streptomyces tsukubaensis. It is reported that FK-506 prolongs the viability of allogenic grafts of the heart and kidney in vivo and inhibits the development of autoimmune diseases. Furthermore, immunosuppressive therapy of myocarditis in humans has been given special attention by various observers; however, it is controversial. This study investigates the effects of FK-506 on experimental autoimmune myocarditis in rats. We performed two experiments. In Experiment 1, FK-506 was given intramuscularly on Days 11-20 after the first immunization. The rats were immunized twice (on Day 0 and Day 7). They were injected subcutaneously in the footpads with 1.0 mg of human cardiac myosin in equal volumes of complete Freund's adjuvant supplemented with Mycobacterium tuberculosis. They were divided into four groups: Control (six rats, saline), group 1 (six rats, FK-506: 0.1 mg/kg/day), group 2 (seven rats, FK-506: 0.32 mg/kg/day), and group 3 (six rats, FK-506: 1.0 mg/kg/day). To investigate the histologic extent of myocarditis, we formulated a histologic score (0-3). Histologic scores were: Control, 1.90 +/- 0.14; group 1, 0.97 +/- 0.46; group 2, 0.03 +/- 0.05; and group 3, 0 +/- 0. The indices of heart weight/body weight were: Control, 0.74 +/- 0.10%; group 1, 0.45 +/- 0.05%; group 2, 0.35 +/- 0.03%; and group 3, 0.35 +/- 0.03%. In Experiment 2, FK-506 was given on Days 1-10 after the first immunization, earlier than in Experiment 1. The rats were similarly divided into four groups. Each group was given the same dose of FK-506 as in Experiment 1. Histologic scores were: Control 1.49 +/- 0.24; group 1, 1.60 +/- 0.22; group 2, 0.29 +/- 0.41; and group 3, 0.03 +/- 0.03. The indices of heart weight/body weight were: Control, 0.69 +/- 0.15%; group 1, 0.76 +/- 0.09%; group 2, 0.42 +/- 0.08%; and group 3, 0.37 +/- 0.03%. Accordingly, in Experiments 1 and 2, the effects of FK-506 on autoimmune myocarditis were dose-dependent. On the other hand, in Experiments 1 and 2, not only in the control group but also in all treated groups, the titers of anti-myosin IgG were high. In conclusion, even if it is administered just before the onset of myocarditis, FK-506 is extremely effective at suppressing autoimmune myocarditis, despite a high titer of anti-myosin IgG.

Topics: Animals; Antibodies; Autoimmune Diseases; Body Weight; Male; Myocarditis; Myosins; Organ Size; Rats; Rats, Inbred Lew; Tacrolimus

FK506, a new immunosuppressant, caused glucose intolerance in rats given daily oral doses of 1, 5, or 10 mg/kg/day for 14 days, but did not induce hyperglycemia under normal feeding. Besides the glucose intolerance, insulin secretion was impaired and insulin levels in the pancreas were lowered. Histopathologically, there was vacuolation of the Langerhans islets in the animals given 10 mg/kg. After withdrawal of the drug, these changes in pancreatic function and morphology returned to normal within 2 weeks. The findings indicate that FK506 caused dose-dependent but reversible islet toxicity in rats.

Topics: Animals; Blood Glucose; Body Weight; Eating; Insulin; Islets of Langerhans; Male; Rats; Rats, Inbred Strains; Tacrolimus

Topics: Animals; Body Weight; Graft Rejection; Graft Survival; Graft vs Host Reaction; Jejunum; Rats; Rats, Inbred BN; Rats, Inbred Lew; Tacrolimus; Transplantation, Homologous

Effect of pretreatment of rats with FK506((-)-(1R,9S,12S,13R,14S,17R,18E,21S,23S,24R,25S,27R)-17-allyl-1,14- dihydroxy-12-[(E)-2-[(1R,3R,4R)-4-hydroxy-3methoxycyclohexyl]-1- methylvinyl]-23,25-dimethoxy-13,19,21,27-tetramethyl-11,28-dioxa-4- azatricyclo-[22.3.1.0(4.9)]octacos-18-ene-2,3,10,16-tetrone hydrate, CAS 104987-11-3) on microsomal cytochrome P-450 system and oxidations of the administered drug and other model substrates were studied and compared with those of a pharmacologically related drug, ciclosporin (cyclosporin A). Oral treatment of male Sprague-Dawley rats with FK506 (0.4, 2 or 10 mg/kg/d) for 7 days did not decrease microsomal content of total cytochrome P-450 in livers, but rather increased the content in groups with the dose of 0.4 or 10 mg/kg to the levels of 126-130% of the control. Microsomal NADPH-cytochrome c reductase activities were decreased up to 67% of the control with the increasing dose of FK506 and to 62% in a group treated orally with cyclosporin A (25 mg/kg/d for 7 days), although another microsomal electron-transport component, cytochrome b5, was rather increased in all the treated groups. Treatment with FK506 or cyclosporin A did not reduce but slightly increased microsomal activities of aniline hydroxylation, p-nitroanisole O-demethylation and O-ethoxyresorufin O-deethylation. Microsomal depropylation of 7-propoxycoumarin, a typical P-450IIIA-substrate, was also not reduced in all dose groups of FK506, while it was decreased by the treatment with 25 mg/kg cyclosporin A.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Animals; Body Weight; Chromatography, High Pressure Liquid; Cyclosporine; Immunosuppressive Agents; In Vitro Techniques; Indicators and Reagents; Liver; Metyrapone; Microsomes, Liver; Mixed Function Oxygenases; Organ Size; Proteins; Rats; Rats, Inbred Strains; Spectrometry, Fluorescence; Tacrolimus

The in vitro potency of the immunosuppressants Cyclosporin A (CsA), FK-506 and Prednisolone was assessed using the adoptive transfer model of EAE in the Lewis rat. Co-culture of encephalitogen-sensitised splenic leukocytes with Prednisolone did not inhibit the transfer of disease to naive histocompatible recipients despite significant suppression of neuroantigen-stimulated leukocyte proliferation by the drug. The addition of CsA (100 nM) to cultures inhibited the induction of adoptive EAE but a lower dose of the agent (10 nM) did not prevent the development of clinico-histopathological signs of disease. FK-506 (1 nM) was 100 times more effective than CsA at suppressing adoptive EAE thus emphasising the usefulness of the model in determining the relative efficacy of compounds to modify cell-dependent autoimmune disease.

Topics: Animals; Body Weight; Cell Division; Cells, Cultured; Cyclosporine; Encephalomyelitis, Autoimmune, Experimental; Immunization, Passive; Leukocyte Transfusion; Leukocytes; Male; Myelin Basic Protein; Prednisolone; Rats; Rats, Inbred Lew; Spleen; Tacrolimus

Topics: Adult; Age Factors; Aged; Anti-Bacterial Agents; Blood Group Antigens; Body Weight; Child; Cyclosporins; Female; Hepatitis, Viral, Human; Humans; Immunosuppression Therapy; Immunosuppressive Agents; Liver Diseases; Liver Transplantation; Male; Sex Factors; Survival Analysis; Tacrolimus

The BB rat is the experimental analogue of human juvenile diabetes mellitus. From 30 through 120 days after birth, 59 BB rats were treated with water (n = 20), or FK 506 in daily intragastric doses of 1 mg/kg (n = 19) or 2 mg/kg (n = 20). Diabetes developed in 75%, 15%, and 0% of the three groups. Animals protected from diabetes by FK 506, and killed in the nondiabetic state at 120 days had normal intraperitoneal glucose tolerance tests, virtual absence histopathologically of autoimmune insulitis, normal pancreatic insulin content, and immunocytochemical confirmation of islet insulin and glucagon content. Forty five to 75 days after stopping FK 506, about 3/4 of the animals who were diabetes free at 120 days have remained so. These results provide support for a clinical trial of FK 506 for recent onset diabetes.

Topics: Animals; Anti-Bacterial Agents; Blood Glucose; Body Weight; Diabetes Mellitus, Experimental; Female; Glucose Tolerance Test; Immunosuppressive Agents; Insulin; Islets of Langerhans; Male; Rats; Rats, Inbred BB; Rats, Inbred WF; Tacrolimus

Abdominal multivisceral allotransplantation (MVTX) from Brown Norway donor rats to Lewis recipient rats was performed under a 14-day course of low (0.32 mg/kg) or high-dose (0.64 mg/kg) intramuscular FK 506 to which weekly further injections were added in some of the high-dose animals. With all three regimens, long survival was frequently achieved with good intestinal adsorption and weight gain, but histopathologic evidence of intestinal rejection existed in the most lightly treated animals. The liver, stomach, and pancreas had only minor abnormalities. Rejection of isolated intestinal grafts was more difficult to control based on histopathologic criteria, and satisfactory results were obtained only with the most aggressive treatment protocol, suggesting that the liver in the MVTX had provided an advantage to the companion organs of the graft, of which the intestine was most vulnerable. Histopathologically, the lymphoid elements of the intestine, including the Peyer's patches, appeared to be the most immunogenic component of the intestine. Epithelium near lymphoid areas was secondarily involved with villous atrophy, cryptitis, and abscess formation. Beginning within 12 days in successful MVTX experiments, the lymphoreticular components of the graft intestine, including the Peyer's patches, lamina propria, and mesenteric nodes, were shown with anti-Ia monoclonal antibodies to be repopulated with recipient cells. This finding in grafts that appeared to be permanently accepted was surprising and contrary to expectations from the literature on intestinal allotransplantation.

Topics: Animals; Anti-Bacterial Agents; Body Weight; Immunohistochemistry; Immunosuppressive Agents; Intestine, Small; Male; Rats; Rats, Inbred Lew; Rats, Inbred Strains; Staining and Labeling; Survival Analysis; Tacrolimus; Time Factors; Transplantation; Transplantation, Homologous; Viscera

Topics: Animals; Blood Pressure; Blood Urea Nitrogen; Body Weight; Creatinine; Heart Rate; Juxtaglomerular Apparatus; Kidney Cortex; Mice; Mice, Inbred ICR; Potassium; Reference Values; Regional Blood Flow; Renal Circulation; Renin; Tacrolimus

Topics: Animals; Body Weight; Budesonide; Cyclosporine; Diabetes Mellitus, Experimental; Glucocorticoids; Graft Survival; Injections, Intravenous; Islets of Langerhans Transplantation; Portal Vein; Pregnenediones; Rats; Rats, Inbred Lew; Rats, Inbred WF; Tacrolimus; Transplantation, Homologous

Topics: Alkaline Phosphatase; Animals; Anti-Bacterial Agents; Aspartate Aminotransferases; Bilirubin; Body Weight; Graft Rejection; Immunosuppressive Agents; Liver Transplantation; Macaca fascicularis; Tacrolimus

Topics: Animals; Anti-Bacterial Agents; Body Weight; Cyclosporins; Graft Rejection; Graft vs Host Disease; Immunosuppressive Agents; Intestine, Small; Rats; Rats, Inbred ACI; Rats, Inbred Lew; Tacrolimus; Time Factors

Small intestine allotransplantation in humans is not yet feasible due to the failure of the current methods of immunosuppression. FK-506, a powerful new immunosuppressive agent that is synergistic with cyclosporine, allows long-term survival of recipients of cardiac, renal, and hepatic allografts. This study compares the effects of FK-506 and cyclosporine on host survival, graft rejection, and graft-versus-host-disease in a rat small intestine transplantation model. Transplants between strongly histoincompatible ACI and Lewis (LEW) strain rats, and their F1 progeny are performed so that graft rejection alone is genetically permitted (F1----LEW) or GVHD alone permitted (LEW----F1) or that both immunologic processes are allowed to occur simultaneously (ACI----LEW). Specific doses of FK-506 result in prolonged graft and host survival in all genetic combinations tested. Furthermore, graft rejection is prevented (ACI----LEW model) or inhibited (rejection only model) and lethal acute GVHD is eliminated. Even at very high doses, cyclosporine did not prevent graft rejection or lethal GVHD, nor did it allow long-term survival of the intestinal graft or the host. Animals receiving low doses of cyclosporine have outcomes similar to the untreated control groups. No toxicity specific to FK-506 is noted, but earlier studies by other investigators suggest otherwise.

Topics: Animals; Anti-Bacterial Agents; Body Weight; Cyclosporins; Graft Rejection; Graft vs Host Disease; Immunosuppressive Agents; Intestine, Small; Male; Rats; Rats, Inbred ACI; Rats, Inbred Lew; Survival Analysis; Tacrolimus

Topics: Animals; Anti-Bacterial Agents; Body Weight; Dogs; Duodenum; Graft Rejection; Immunosuppressive Agents; Injections, Intramuscular; Injections, Intravenous; Pancreas Transplantation; Postoperative Complications; Tacrolimus; Thrombosis; Transplantation, Homologous

The effect of administration of FK506 at 1 mg/kg body weight for 14 days on rat lymphoid tissues, especially the thymus, and recovery after discontinuation of treatment, were investigated by the immunoperoxidase technique and flow cytofluorometry using monoclonal antibodies OX6, OX7, OX8, OX18 and W3/25, reactive with rat lymphocytes. Marked reduction of the thymic medulla upon treatment was clearly demonstrated by staining with OX18 and OX6. Changes produced by FK506 were also observed in the cortical area of the thymus, and were especially marked in the subcapsular area and around blood vessels. Eventually, the thymic cortex appeared patchy, this change being maximal 14 days after the start of administration. Obvious restitution of the thymic medulla was evident about 14 days after withdrawal of FK506. Flow cytometric analysis of the thymus showed that the percentages of cells labelled positively with OX7, OX8 and W3/25 were increased with FK506 treatment, and recovered to the normal level soon after withdrawal. Furthermore, the peak of fluorescence intensity of OX7+, OX8+ and W3/25+ cells showed a temporary shift to the right during FK506 treatment; however, the peak of fluorescence intensity of OX18+ cells showed a temporary shift to the left. Treatment with FK506 also produced a significant change in 3H-thymidine uptake by thymocyte. These results suggest that FK506 may inhibit the proliferation, maturation and differentiation of thymocytes. However, thymocytes prepared from FK506-treated rats and labelled with FITC behaved similarly to rat thymocytes in normal recipient rats. This suggests that during FK506 treatment thymocytes may retain their potential for peripheral mobilization.

Topics: Animals; Anti-Bacterial Agents; Antibody Formation; Body Weight; Flow Cytometry; Immunoenzyme Techniques; Immunosuppressive Agents; Male; Organ Size; Rats; Rats, Inbred Lew; Spleen; Tacrolimus; Thymus Gland; Time Factors

We investigated the superior potency of the immunosuppressive agent FK506 on collagen-induced arthritis in rats. In our initial studies, we demonstrated that only one shot administration of FK506 at a dose of 10 mg/kg on the same day as type II collagen immunization suppressed the incidence of arthritis completely as well as humoral and delayed-type hypersensitivity (DTH) skin test responses to type II collagen. Yet no major side effects were observed in the rats treated with such a high dose of FK506. Additional studies demonstrated that pretreatment with FK506 on day -7 or day -3 was effective in suppressing the severity of arthritis and immune responses to type II collagen. The immunosuppressive effect of a single high-dose administration of FK506 continued for at least 1 week in this animal model of arthritis. A single administration of FK506 at a dose of 10 mg/kg on day 12 or 15, after the clinical onset of arthritis, was also effective in suppressing the severity of arthritis and immune response to type II collagen. We conclude that FK506, in this model, possesses an important, curative action when applied therapeutically. The outlook of FK506 treatment in clinical autoimmunity is promising at present.

Topics: Animals; Anti-Bacterial Agents; Arthritis; Body Weight; Collagen; Dose-Response Relationship, Drug; Female; Immunosuppressive Agents; Rats; Rats, Inbred Strains; Tacrolimus

The effects of two novel immunosuppressants, FK506 and 15-deoxyspergualin (15-DSG), on experimental autoimmune uveoretinitis (EAU) were evaluated in the rat. Rats were immunized with retinal soluble antigen (S-antigen) and treated with FK506 or 15-DSG, and the disease induction as well as the immune responses to the antigen were examined. The results were compared with animals treated with cyclosporine (CsA) which has been widely used to treat refractory uveitis in humans. A dose-response study showed that FK506 suppressed EAU induction at doses 10-30 times lower CsA when given on days 0-14 postimmunization, while 15-DSG suppressed the disease development at doses very similar to CsA. As with CsA, FK506 suppressed EAU induction when given only in the induction phase (days 0-5 postimmunization) or in the effector phase (days 7-12), but at doses much lower than CsA. On the other hand, 15-DSG suppressed EAU only at toxic doses with these schedules. The antigen specific mitotic response of lymphocytes was markedly suppressed by the three agents, while the antigen specific antibodies in sera were suppressed by 15-DSG and FK506 but not by CsA at doses effective in suppressing the disease induction. More significant findings were uniquely prolonged immunosuppressive effects of FK506: EAU induction as well as the immune responses to S-antigen were suppressed long after the cessation of drug treatment.

Topics: Animals; Antibodies; Antigens; Arrestin; Autoimmune Diseases; Body Weight; Cyclosporine; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Administration Schedule; Drug Evaluation, Preclinical; Enzyme-Linked Immunosorbent Assay; Eye; Eye Proteins; Guanidines; Immunosuppressive Agents; Male; Rats; Rats, Inbred Lew; Tacrolimus; Uveitis

The immunosuppressive and toxic properties of the recently discovered macrolide antibiotic FK506 were examined in comparison and in conjunction with cyclosporine administration in the rat. Male Sprague-Dawley rats were immunized systemically with sheep erythrocytes and received, from the same time, either FK506 (1 mg/kg/day) intramuscularly or CsA (25 mg/kg/day) by gavage, or both drugs in combination. Seven days after immunization, the splenic plaque-forming cell response and circulating antibody titers were reduced greater than 90% in animals receiving either FK506 or CsA and in the drug combination group. These immunosuppressive effects of FK506 and CsA were accompanied by significant increases in the incidences of splenic OX-8+ cells and by corresponding reductions in the W3/25+:OX-8+ ratio. No further changes in T cell populations were observed in animals given both drugs. A progressive monocytosis was found in response to CsA, but not in FK506-treated rats. Increases in plasma urea were observed in FK-506 and drug-combination or CsA-treated rats on day 7, whereas creatinine levels were raised only in the FK-506 groups. Elevated bilirubin levels and alterations in liver enzyme activities were observed in CsA-treated rats by day 4, whereas FK-506 alone produced no similar effects. CsA-treated rats also exhibited elevated blood and urinary glucose levels from day 4. No biochemical evidence of additive drug toxicity was detected. The only histological abnormalities observed were thymic medullary atrophy in all drug-treated animals, together with very minor reductions in bone marrow cellularity in a proportion of those rats given FK-506. These findings show that, at the dosage selected, the powerful immunosuppressive activities of FK-506 were associated with little evidence of acute toxicity and with no indications of additive toxicity with CsA.

Topics: Animals; Antibody Formation; Antigens, Surface; Blood Glucose; Body Weight; Cyclosporins; Drug Synergism; Flow Cytometry; Glycosuria; Immunosuppression Therapy; Immunosuppressive Agents; Kidney; Leukocyte Count; Liver; Lymphocytes; Pyridines; Rats; Rats, Inbred Strains; Tacrolimus; Thymus Gland

The immunosuppressive agent FK permitted increased kidney transplant survival in dogs over a wide dose range, but with weight loss and manifold evidence of toxicity. The best use of FK at low doses was in combination with CyA and Pred.

Topics: Animals; Body Weight; Cyclosporins; Dogs; Drug Evaluation, Preclinical; Drug Synergism; Drug Therapy, Combination; Graft Rejection; Immunosuppressive Agents; Kidney Transplantation; Prednisolone; Pyridines; Tacrolimus; Vomiting

Ten dogs that survived the perioperative events of liver transplantation were treated with 1 mg/kg/d oral FK. Eight of the recipients lived for at least 1 month postoperatively, and seven are still alive with normal hepatic function after 35 to 65 days. The consistency and good quality of results with this difficult transplant preparation using FK, in spite of its rumored great toxicity in dogs, have highlighted the importance of further developing the drug.

Topics: Animals; Body Weight; Dogs; Drug Evaluation, Preclinical; Graft Rejection; Immunosuppressive Agents; Liver Function Tests; Liver Transplantation; Pyridines; Tacrolimus

Topics: Animals; Blood Vessels; Body Weight; Drug Evaluation, Preclinical; Immunosuppressive Agents; Male; Pancreas; Pyridines; Rats; Rats, Inbred Lew; Tacrolimus; Thymus Gland