sirolimus and Hyperglycemia

Phosphoinositide-3-kinase/Akt/mammalian target of rapamycin (PI3K/Akt/mTOR) pathway inhibitors are a novel class of antineoplastic agent available for the treatment of various cancers. With improved cancer outcomes and survival, individuals are exposed to these antineoplastic therapies for longer periods of time and therefore, the consideration of adverse effects is of increasing importance. The PI3K/Akt/mTOR signaling pathway plays a critical role in regulating cellular processes such as growth and proliferation, but also regulates the metabolic effects of insulin such as glucose uptake and glycogen synthesis. Therefore, hyperglycemia and insulin resistance are frequently reported adverse effects. There are no recent consensus guidelines on the management of hyperglycemia secondary to PI3K/Akt/mTOR inhibitors, with the latest guidelines produced in 2012 - when many of these agents were still undergoing development. As we now have a greater understanding of the underlying mechanisms and patterns in which hyperglycemia is induced and access to an increasing array of glucose-lowering agents, an update of the previous guidelines accommodating these understandings and developments is timely. This review will provide a comprehensive summary of the current literature with regards to the incidence of hyperglycemia associated with each agent, as well as the different pathways and mechanisms in which hyperglycemia is induced. Our proposed up-to-date strategy for the specific management of PI3K/Akt/mTOR inhibitor-induced hyperglycemia will also aim to facilitate management of this complex oncological population.

Topics: Antineoplastic Agents; Humans; Hyperglycemia; Neoplasms; Phosphatidylinositol 3-Kinase; Phosphatidylinositol 3-Kinases; Phosphatidylinositols; Phosphoinositide-3 Kinase Inhibitors; Protein Kinase Inhibitors; Proto-Oncogene Proteins c-akt; Sirolimus; TOR Serine-Threonine Kinases

The mammalian targets of rapamycin (mTOR) inhibitors are potent immunosuppressors used for prevention of acute rejection after transplantation and have been more recently used as anticancer drugs. mTOR inhibitors have a significant impact on glucose metabolism and frequently induce diabetes. mTOR inhibitors, when used as immunosuppressive agents (sirolimus, everolimus), can induce diabetes with an incidence which is low when used without calcineurin inhibitors but high when used in combination with calcineurin inhibitors (from 11.0% to 38.1%). mTOR inhibitors used as anticancer agents (everolimus, temsirolimus) increase significantly the risk for new-onset diabetes and induce a 5-fold increase in the risk for severe hyperglycemia. The deleterious effect of mTOR inhibitors on glucose metabolism is due to an increased insulin resistance secondary to a reduction of the insulin signaling pathway within the cell and a reduction of insulin secretion via a direct effect on the pancreatic beta cells. Because of the risk for diabetes, it is recommended, when starting a treatment with an mTOR inhibitor, to check fasting blood glucose every 2 weeks during the first month of treatment then every month and HbA1c every 3 months and to intensify self-monitoring of blood glucose in patients with known diabetes. When fasting blood glucose is more than 126 mg/dL (7.0 mmol/L), when plasma glucose is more than 200 mg/dL at any time, or when HbA1c is more than 6.5%, it is recommended to start antidiabetic treatment.

Topics: Diabetes Mellitus, Type 2; Everolimus; Humans; Hyperglycemia; Protein Kinase Inhibitors; Sirolimus; TOR Serine-Threonine Kinases

Post-transplant diabetes mellitus is a significant risk factor for cardiovascular disease in solid organ transplantation. The main underlying pathophysiological mechanism of PTDM is pancreatic beta cell dysfunction in the context of insulin resistance, but the relative importance of each of these important components of glycemic metabolism is under intense debate.. We searched MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials to January 15, 2015. We selected systematic reviews and meta-analyses and randomized clinical trials. When no such reports were found for a given topic or drug, observational studies were included in the assessment.. There are agents with known diabetogenic effects: corticosteroids, calcineurin inhibitors including tacrolimus and cyclosporine, as well as the mammalian target of rapamycin inhibitors (sirolimus and everolimus). The association between the use of induction agents and PTDM is very scarce. No diabetogenic effects have been found with the use of azathioprine, mycophenolate mofetil and its derivatives.. Immunosuppression is the major modifiable risk factor for development of PTDM but risk versus benefit analysis is required to balance risk of developing PTDM versus rejection. Caution is advisable in immunosuppressant adjustments in the event that PTDM develops based on current evidence. Physicians should choose and use immunosuppression regimens shown to have the best outcome for patient and graft survival, irrespective of PTDM risk.

Topics: Adrenal Cortex Hormones; Azathioprine; Calcineurin Inhibitors; Cyclosporine; Diabetes Mellitus; Everolimus; Graft Rejection; Humans; Hyperglycemia; Immunosuppressive Agents; Mycophenolic Acid; Postoperative Complications; Sirolimus; Tacrolimus; TOR Serine-Threonine Kinases; Transplantation

mTOR inhibitors are now approved by regulatory agencies for the treatment of a variety of malignancies. The risk of metabolic complications with these agents is not well characterized.. PubMed was searched for articles published from 2001 until 2011. Eligible studies included prospective randomized trials evaluating temsirolimus, everolimus, and ridaforolimus in patients with all solid tumor malignancies. Sixteen eligible phase II clinical trials and 8 randomized controlled clinical trials were included in a systematic review and meta-analysis and the number of metabolic related AEs (hyperglycemia, hypercholesterolemia, and hypertriglyceridemia) was extracted. Incidence rates and incident rate ratios were calculated.. Twenty-four trials, including 4261 patients, were included in the calculation of the incidence rate. The average incidence rate of all grade metabolic related events was 0.70 (95% CI, 0.47, 0.93). The average incidence rate of serious (grade 3 and 4) metabolic related adverse events was 0.11 (95% CI, 0.08, 0.15). The incidence rate ratio (IRR) of a metabolic adverse event with mTOR inhibitor therapy compared with control was 2.93 (95% CI, 2.33, 3.70) and of serious grade 3 and 4 metabolic adverse events was 4.58 (95% CI, 2.86, 7.34). The IRR of all grade hyperglycemia was 2.95 (95% CI, 2.14, 4.05) and of grade 3-4 hyperglycemia was 5.25 (95% CI, 3.07, 9.00). The IRR of all grade hypertriglyceridemia was 2.49 (95% CI, 1.76, 3.52) and of grade 3-4 hypertriglyceridemia was 2.01 (95% CI, 0.65, 6.27). The IRR of all grade hypercholesterolemia was 3.35 (95% CI, 2.17, 5.18) and of grade 3-4 hypercholesterolemia was 6.51 (95% CI, 1.48, 28.59). These findings suggest a statistically significant increase in the risk of hyperglycemia, hypercholesterolemia (all grades and grade 3 and 4), and all grade hypertriglyceridemia associated with mTOR therapy when compared with control.. The risk of all grade and grade 3-4, hyperglycemia, hypercholesterolemia, and hypertriglyceridemia, are increase in patients treated with mTOR inhibitors compared with control.

Topics: Antibiotics, Antineoplastic; Dyslipidemias; Everolimus; Humans; Hyperglycemia; Incidence; Neoplasms; Randomized Controlled Trials as Topic; Sirolimus; TOR Serine-Threonine Kinases

Statins are currently able to stabilize atherosclerotic plaques by lowering plasma cholesterol and pleiotropic effects, but a residual risk for atherosclerotic disease remains. Therefore, effective prevention of atherosclerosis and treatment of its complications is still a major clinical challenge. A large body of evidence indicates that mammalian target of rapamycin (mTOR) inhibitors such as rapamycin or everolimus have pleiotropic anti-atherosclerotic effects so that these drugs can be used as add-on therapy to prevent or delay the pathogenesis of atherosclerosis. Moreover, bioresorbable scaffolds eluting everolimus trigger a healing process in the vessel wall, both in pigs and humans, that results in late lumen enlargement and plaque regression. At present, this phenomenon of atheroregression is poorly understood. However, given that mTOR inhibitors suppress cell proliferation and trigger autophagy, a cellular survival pathway and a process linked to cholesterol efflux, we hypothesize that these compounds can inhibit (or reverse) the basic mechanisms that control plaque growth and destabilization. Unfortunately, adverse effects associated with mTOR inhibitors such as dyslipidemia and hyperglycemia have recently been identified. Dyslipidemia is manageable via statin treatment, while the anti-diabetic drug metformin would prevent hyperglycemia. Because metformin has beneficial macrovascular effects, this drug in combination with an mTOR inhibitor might have significant promise to treat patients with unstable plaques. Moreover, both statins and metformin are known to inhibit mTOR via AMPK activation so that they would fully exploit the beneficial effects of mTOR inhibition in atherosclerosis.

Topics: Absorbable Implants; AMP-Activated Protein Kinases; Animals; Apolipoproteins E; Cholesterol; Clinical Trials as Topic; Coronary Artery Disease; Drug Evaluation, Preclinical; Drug Interactions; Drug Therapy, Combination; Drug-Eluting Stents; Dyslipidemias; Everolimus; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Hyperglycemia; Macrophages; Metformin; Mice; Mice, Knockout; Plaque, Atherosclerotic; Rabbits; Receptors, LDL; Rupture, Spontaneous; Sirolimus; Swine; Tissue Scaffolds; TOR Serine-Threonine Kinases; Triglycerides

Medical management of pancreatic neuroendocrine tumors has recently been improved by new molecules of which the mTOR inhibitor everolimus. If digestive neuroendocrine tumors are rare, the incidence is in constant increase and the prevalence in digestive cancers put them right behind colorectal cancers. Everolimus has demonstrated efficacy in unresectable and progressive pancreatic neuroendocrine tumors, by doubling the median progression free survival (11 versus 4.6 months), with a median time of exposure to everolimus of nine months. Everolimus is generally maintained until progression or intolerance and some patients are treated during several years. Potential metabolic disorders induced by everolimus (dyslipidemia, hyperglycemia) in patients with life expectancy of several years, justify monitoring of these parameters and accurate treatment management algorithm. These will avoid worsening patient's prognostic, but also prematurely discontinue potentially effective treatment or contraindicate other therapeutic weapons, in a pathology in which there are multiple therapeutic options in metastatic phase. We propose a standard practice in terms of initial assessment, monitoring, care threshold, and therapeutic objectives to manage metabolic disorders, fitted to our patients with advanced pancreatic neuroendocrine tumors.

Topics: Dyslipidemias; Everolimus; Humans; Hyperglycemia; Neuroendocrine Tumors; Pancreatic Neoplasms; Sirolimus

Everolimus is a mammalian target of rapamycin (mTOR) inhibitor approved for the treatment of advanced renal cell carcinoma, pancreatic neuroendocrine tumors, subependymal giant cell astrocytoma associated with tuberous sclerosis complex, renal angiomyolipoma and tuberous sclerosis complex, and, in combination with exemestane, for hormone receptor-positive HER2-negative advanced breast cancer after failure of treatment with letrozole or anastrozole. Results from the phase III BOLERO-2 trial demonstrated that everolimus in combination with exemestane provided significant clinical benefit to patients with advanced hormone receptor-positive breast cancer. Although everolimus is generally well tolerated, as with most therapies administered in an advanced cancer setting, drug-related adverse events (AEs) inevitably occur. Most common AEs observed in the everolimus studies include stomatitis, rash, infection, noninfectious pneumonitis, and hyperglycemia. Clinical awareness and early identification of such AEs by oncology nurses are essential to dosing (interruptions, reduction, and treatment discontinuation); quality of life; and, ultimately, patient outcomes. Because everolimus has already been shown to significantly improve clinical efficacy in patients with advanced breast cancer, a proactive approach to the practical management of AEs associated with this mTOR inhibitor as well as other most common AEs observed in this patient population has been reviewed and outlined here.

Topics: Adult; Androstadienes; Antineoplastic Agents; Breast Neoplasms; Clinical Trials, Phase III as Topic; Everolimus; Exanthema; Female; Humans; Hyperglycemia; Pneumonia; Sirolimus; Stomatitis; Treatment Outcome

Everolimus is an orally available inhibitor of the mammalian target of rapamycin (mTOR), which has been approved in combination with exemestane for hormone receptor-positive (HR) breast cancer after failure of treatment with non-steroidal aromatase inhibitors. Everolimus is generally very well tolerated with most common side effects including stomatitis, rash, fatigue, hyperglycemia, hyperlipidemia, and myelosuppression. Most of these side effects are mild and resolve with dose interruptions or dose reductions. Symptomatic non-infectious pneumonitis is a relatively uncommon class effect of mTOR inhibitors, which can be life threatening. Given the efficacy of everolimus in HR-positive metastatic breast cancer, it is crucial for physicians to recognize toxicities related to everolimus and start timely interventions. This review will focus on the adverse events reported with everolimus in breast cancer trials and will provide practical guidelines for the management of these adverse events.

Topics: Antineoplastic Agents; Breast Neoplasms; Everolimus; Fatigue; Female; Humans; Hyperglycemia; Hyperlipidemias; Pneumonia; Sirolimus; Stomatitis; TOR Serine-Threonine Kinases

Cixutumumab (a humanized monoclonal antibody against insulin-like growth factor-1 receptor [IGF-1R]) and the mammalian target of rapamycin (mTOR) inhibitor temsirolimus were combined in a phase I study of patients with advanced cancer. We investigated the prevalence of metabolic toxicities, their management, and impact on outcome.. The temsirolimus dose was 25 mg or 37.5 mg i.v. weekly with escalating doses of cixutumumab (3, 5, or 6 mg/kg i.v. weekly). No patients with diabetes or hyperlipidemia at baseline were eligible until the expansion cohort. We assessed metabolic derangements in our patient cohort, their management, and their association with tumor shrinkage, time to progression (TTP) and overall survival (OS).. Of the 57 patients analyzed, hyperglycemia was seen in 36 (63%) (grade 1-2: 33 [58%]; grade 3-4: 3 [5%]). The median blood sugar level (fasting and nonfasting) across cohorts was 149 mg/dL (upper limit of normal: 110 mg/dL). No patient developed diabetic ketoacidosis or nonketotic hyperosmolar coma or pancreatitis during treatment. Median maximum triglyceride, cholesterol, and low-density lipoprotein levels achieved were 247 mg/dL (range: 65-702 mg/dL), 243 mg/dL (range: 103-424 mg/dL), and 153 mg/dL (range 50-375 mg/dL), respectively. Higher glucose levels were associated with more RECIST tumor shrinkage (r = -.30 [95% confidence interval: -.52, -.03; p = .03]). There was no association between metabolic toxicities of the mTOR and IGF-1R combination and TTP or OS.. The combination of temsirolimus and cixutumumab was safe and resulted in manageable metabolic toxicities. More tumor shrinkage was seen in patients who developed these adverse events. Although perhaps limited by the small number of patients, no significant association was discerned between hyperglycemia, hypertriglyceridemia, or hypercholesterolemia and TTP or OS.. Results of this study show that the combination of temsirolimus and cixutumumab is safe. The most common side effects, hyperglycemia and hyperlipidemia, are tolerable and manageable. This combination of therapies should not be withheld from diabetic patients and patients with high cholesterol levels. Collaboration between oncologist and endocrinologist allows for individualized treatment and better control of these adverse events, with few dose interruptions and reductions. Supportive care and close monitoring is needed. Those patients who develop hyperglycemia or hypercholesterolemia may benefit more from the drug.

Topics: Adolescent; Adult; Aged; Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Antineoplastic Combined Chemotherapy Protocols; Female; Humans; Hypercholesterolemia; Hyperglycemia; Hyperlipidemias; Male; Middle Aged; Neoplasms; Receptor, IGF Type 1; Sirolimus; Survival Analysis; TOR Serine-Threonine Kinases; Treatment Outcome; Young Adult

The prognosis for women with recurrent and metastatic endometrial cancer is poor, and improved therapies are needed. The mammalian target of rapamycin (mTOR) pathway is an important target, and mTOR inhibitors show clinical activity in endometrial cancer.. An open-label, multicenter, randomized, phase II trial of oral ridaforolimus compared with progestin or investigator choice chemotherapy (comparator) was undertaken in women with metastatic or recurrent endometrial cancer who had progressive disease following one or two lines of chemotherapy and no hormonal therapy. The primary end point was progression-free survival (PFS) assessed by independent radiologic review.. One hundred thirty patients were enrolled (64 received ridaforolimus and 66 received the comparator), and median age was 66 years. Treatment discontinuation as a result of adverse events was 33% with ridaforolimus versus 6% with the comparator, with common (> 10%) grade 3 toxicities being hyperglycemia, anemia, and diarrhea. Thirty-eight percent (ridaforolimus) versus 71% (comparator) of patients discontinued treatment as a result of disease progression. Median PFS at the protocol prespecified interim analysis with 58 PFS events (primary end point) was 3.6 months (95% CI, 2.7 to 7.3 months) for ridaforolimus and 1.9 months (95% CI, 1.9 to 2.3 months) for the comparator (hazard ratio, 0.53; 95% CI, 0.31 to 0.90; P = .008). PFS rate for ridaforolimus versus comparator was 48% versus 18% at 16 weeks and 38% versus 15% at 24 weeks. Objective response rate for ridaforolimus versus comparator was 0% versus 4% (P = .925), and stable disease was achieved in 35% versus 17% of patients (P = .021).. Oral ridaforolimus shows encouraging activity in advanced endometrial cancer but is associated with significant toxicity. Inhibition of the PI3K/Akt/mTOR pathway may be a viable therapeutic target.

Topics: Administration, Oral; Adult; Aged; Aged, 80 and over; Anemia; Antibiotics, Antineoplastic; Diarrhea; Disease-Free Survival; Endometrial Neoplasms; Female; Humans; Hyperglycemia; Kaplan-Meier Estimate; Middle Aged; Progestins; Prognosis; Proportional Hazards Models; Sirolimus; TOR Serine-Threonine Kinases; Treatment Outcome

To retrospectively analyze the effects of treatment duration on outcomes of everolimus treatment of patients in the RAD001 Expanded-Access Clinical Trial in RCC (REACT) program.. Patients with metastatic renal cell carcinoma refractory to vascular endothelial growth factor receptor-tyrosine kinase inhibitor received everolimus (10 mg once daily), with dosing interruption or modifications allowed for toxicity. All serious and grade 3/4 adverse events and grade 1/2 adverse events leading to a change in drug administration were reported. Tumor response was evaluated using Response Evaluation Criteria In Solid Tumors.. The study stratified 1367 evaluable patients into treatment duration groups of <3 months, ≥3 and <6 months, ≥6 months and <1 year, and ≥1 year. Pneumonia, noninfectious pneumonitis, and hyperglycemia occurred more frequently in patients receiving everolimus for ≥1 year but did not result in treatment discontinuations. First occurrence of adverse events presented early in the treatment course for most patients. Treatment duration of ≥6 months was associated with improved disease control rates.. Everolimus is well tolerated in patients with metastatic renal cell carcinoma for treatment durations≥1 year and not associated with cumulative toxicity.

Topics: Aged; Anemia; Antineoplastic Agents; Carcinoma, Renal Cell; Disease Progression; Dyspnea; Everolimus; Fatigue; Female; Humans; Hyperglycemia; Kidney Neoplasms; Male; Middle Aged; Pneumonia; Sirolimus; Stomatitis; Time Factors; Treatment Outcome

The mammalian target of rapamycin complex 1 (mTORC1) is aberrantly activated in many head and neck squamous cell carcinomas (HNSCCs). This phase I study combines the mTORC1 inhibitor temsirolimus with carboplatin and paclitaxel.. This was a single institution phase I study for patients with R/M HNSCC with a standard 3 + 3 design. Three doses of temsirolimus were planned: 15, 20, and 25 mg. Due to excessive toxicity with the original study regimen, the protocol was amended to carboplatin AUC 1.5, paclitaxel 80 mg/m(2), and temsirolimus (according to dose escalation plan), all on days 1 and 8 of a 21-day cycle.. 18 patients (14 male, 4 female) enrolled, with median age 56 years (range 33-78). The most common toxicities were anemia, leukopenia, thrombocytopenia, and hyperglycemia. Among all patients treated, the confirmed objective partial response (cPR) rate was 22 %. DLT was not exceeded among 6 patients treated at dose level 3 of the revised protocol, and 4 of 6 subjects treated at this dose level had cPRs.. The phase II recommended regimen is temsirolimus 25 mg, carboplatin AUC 1.5, and paclitaxel 80 mg/m(2), all on days 1 and 8 of a 21-day cycle. A phase II study of this regimen in R/M HNSCC is ongoing.

Topics: Adult; Aged; Anemia; Antineoplastic Combined Chemotherapy Protocols; Carboplatin; Carcinoma, Squamous Cell; Dose-Response Relationship, Drug; Drug Administration Schedule; Female; Head and Neck Neoplasms; Humans; Hyperglycemia; Leukopenia; Male; Middle Aged; Neoplasm Metastasis; Neoplasm Recurrence, Local; Paclitaxel; Sirolimus; Thrombocytopenia; Treatment Outcome

Temsirolimus, an inhibitor of the mammalian target of rapamycin, is approved for treatment of patients with advanced renal cell carcinoma in the USA and Europe. Temsirolimus was not yet evaluated in East Asian patients.. This non-randomized Phase II study enrolled 82 patients with advanced renal cell carcinoma [20 (24%) Japanese, 30 (37%) Korean and 32 (39%) Chinese patients; median age (range): 55 (26-83) years]. Most (71%) received prior systemic therapy for metastatic disease; two-thirds were intermediate risk. Six Japanese patients received intravenous temsirolimus 20 mg/m(2) weekly for tolerability assessment (Group A); the remaining 76 received a 25 mg flat dose weekly (Group B). Temsirolimus was dosed once weekly. Primary efficacy end point was the Response Evaluation Criteria in Solid Tumors-defined clinical benefit rate in the intent-to-treat population.. In the entire population, regardless of treatment group, the clinical benefit rate was 48% (95% confidence interval: 36, 59). Objective response rate was 11% (95% confidence interval: 5, 20), median progression-free survival was 7.3 months (95% confidence interval: 4.0, 9.2) and median time to treatment failure was 5.4 months (95% confidence interval: 3.5, 7.4). No patient in Group A demonstrated dose-limiting toxicity. The most frequent Grade 3 or 4 drug-related adverse events were anemia, hyperglycemia, hypophosphatemia and stomatitis (5% each). Serious adverse events reported in ≥ 5% of patients were pneumonia (9%) and interstitial lung disease (7%). Temsirolimus and its major metabolite, sirolimus, were long-lived throughout the dosage interval, with no evidence of accumulation.. Temsirolimus was well tolerated and showed promising activity in Japanese, Korean and Chinese patients with advanced renal cell carcinoma.

Topics: Adult; Aged; Anemia; Antineoplastic Agents; Asian People; Carcinoma, Renal Cell; Disease-Free Survival; Drug Administration Schedule; Female; Humans; Hyperglycemia; Hypophosphatemia; Kaplan-Meier Estimate; Kidney Neoplasms; Male; Middle Aged; Outpatients; Protein Kinase Inhibitors; Sirolimus; Stomatitis; Treatment Outcome

Sirolimus is the eponymous inhibitor of the mTOR; however, only its analogs have been approved as cancer therapies. Nevertheless, sirolimus is readily available, has been well studied in organ transplant patients, and shows efficacy in several preclinical cancer models.. Three simultaneously conducted phase I studies in advanced cancer patients used an adaptive escalation design to find the dose of oral, weekly sirolimus alone or in combination with either ketoconazole or grapefruit juice that achieves similar blood concentrations as its intravenously administered and approved prodrug, temsirolimus. In addition, the effect of sirolimus on inhibition of p70S6 kinase phosphorylation in peripheral T cells was determined.. Collectively, the three studies enrolled 138 subjects. The most commonly observed toxicities were hyperglycemia, hyperlipidemia, and lymphopenia in 52%, 43%, and 41% of subjects, respectively. The target sirolimus area under the concentration curve (AUC) of 3,810 ng-h/mL was achieved at sirolimus doses of 90, 16, and 25 mg in the sirolimus alone, sirolimus plus ketoconazole, and sirolimus plus grapefruit juice studies, respectively. Ketoconazole and grapefruit juice increased sirolimus AUC approximately 500% and 350%, respectively. Inhibition of p70 S6 kinase phosphorylation was observed at all doses of sirolimus and correlated with blood concentrations. One partial response was observed in a patient with epithelioid hemangioendothelioma.. Sirolimus can be feasibly administered orally, once weekly with a similar toxicity and pharmacokinetic profile compared with other mTOR inhibitors and warrants further evaluation in studies of its comparative effectiveness relative to recently approved sirolimus analogs.

Topics: Adult; Aged; Aged, 80 and over; Antibiotics, Antineoplastic; Antineoplastic Combined Chemotherapy Protocols; Citrus paradisi; Female; Humans; Hyperglycemia; Hyperlipidemias; Ketoconazole; Lymphopenia; Male; Middle Aged; Neoplasm Staging; Neoplasms; Ribosomal Protein S6 Kinases, 70-kDa; Sirolimus; TOR Serine-Threonine Kinases

Temsirolimus (CCI-779) is a novel inhibitor of the mammalian target of rapamycin. This Phase 1 study was aimed at investigating the maximum-tolerated dose, toxicity, pharmacokinetics and antitumor activity in Japanese patients with advanced solid tumors.. Temsirolimus was given as a 30 min intravenous infusion once a week. Patients with solid tumors not amenable to standard forms of treatment were eligible. Dose escalation of temsirolimus was planned from 15, 45, 80 to 165 mg/m(2). The pharmacokinetics of temsirolimus and sirolimus in whole blood were examined for cycles 1, 2, 4 and 5 of treatment.. Ten patients (median age 60.5 years; range 41-69 years) with advanced solid tumors were enrolled. Their primary cancers were renal cell carcinoma (five patients), lung cancer (three patients) and colorectal cancer (two patients). The major toxicities were hypophosphatemia diarrhea, hyperglycemia, stomatitis, pyrexia, elevated aspartate aminotransferase, rash, reduced neutrophil count, elevated alanine aminotransferase, anorexia, hypertriglyceridemia and somnolence. Two of three patients who received temsirolimus 45 mg/m(2) developed dose-limiting toxicities of Grade 3 stomatitis (one patient) and Grade 3 diarrhea (two patients). The maximum-tolerated dose was 15 mg/m(2). The peak blood concentrations of temsirolimus and sirolimus, a major active metabolite, increased in a dose-dependent manner. The area under the concentration-versus-time curve of sirolimus, but not temsirolimus, increased in a dose-dependent manner.. The recommended dose for Phase 2 clinical studies of temsirolimus in Japanese patients with advanced solid tumors is 15 mg/m(2) intravenously once a week.

Topics: Adult; Aged; Anti-Allergic Agents; Antineoplastic Agents; Area Under Curve; Carcinoma, Renal Cell; Colorectal Neoplasms; Diarrhea; Diphenhydramine; Disorders of Excessive Somnolence; Drug Administration Schedule; Drug Eruptions; Fever; Humans; Hyperglycemia; Hypertriglyceridemia; Hypophosphatemia; Infusions, Intravenous; Intestinal Perforation; Kidney Neoplasms; Lung Neoplasms; Maximum Tolerated Dose; Middle Aged; Neoplasms; Neutropenia; Premedication; Sirolimus; Stomatitis; Treatment Outcome

Standard cytotoxic treatments for neuroendocrine tumours have been associated with limited activity and remarkable toxicity. A phase II study was designed to evaluate the efficacy, safety and pharmacodynamics of temsirolimus in patients with advanced neuroendocrine carcinoma (NEC). Thirty-seven patients with advanced progressive NEC received intravenous weekly doses of 25 mg of temsirolimus. Patients were evaluated for tumour response, time to progression (TTP), overall survival (OS) and adverse events (AE). Twenty-two archival specimens, as well as 13 paired tumour biopsies obtained pretreatment and after 2 weeks of temsirolimus were assessed for potential predictive and correlative markers. The intent-to-treat response rate was 5.6% (95% CI 0.6-18.7%), median TTP 6 months and 1-year OS rate 71.5%. The most frequent drug-related AE of all grades as percentage of patients were: fatigue (78%), hyperglycaemia (69%) and rash/desquamation (64%). Temsirolimus effectively inhibited the phosphorylation of S6 (P=0.02). Higher baseline levels of pmTOR (phosphorylated mammalian target of rapamycin) (P=0.01) predicted for a better response. Increases in pAKT (P=0.041) and decreases in pmTOR (P=0.048) after treatment were associated with an increased TTP. Temsirolimus appears to have little activity and does not warrant further single-agent evaluation in advanced NEC. Pharmacodynamic analysis revealed effective mTOR pathway downregulation.

Topics: Adult; Aged; Antineoplastic Agents; Carcinoid Tumor; Carcinoma, Neuroendocrine; Disease Progression; Exanthema; Fatigue; Female; Follow-Up Studies; Humans; Hyperglycemia; Infusions, Intravenous; Male; Middle Aged; Pancreatic Neoplasms; Phosphorylation; Protein Kinases; Proto-Oncogene Proteins c-akt; Ribosomal Protein S6; Sirolimus; Survival Analysis; TOR Serine-Threonine Kinases; Treatment Outcome

Sirolimus (SRL) is widely used as an immunosuppressant to prevent graft rejection, despite the risk of impairing glucose metabolism. Metformin (MET) can reduce the detrimental effects of SRL in many patients, including diabetes and renal transplant recipients. Limited in vivo studies have reported on SRL and MET therapy, particularly in relation to cellular bioenergetics, glucose metabolism, and insulin resistance. Herein, we investigated the efficacy of SRL and MET co-treatment in BALB/c mice over 4 weeks. Balb/c mice (4-6 weeks old) were divided into four groups and injected intraperitoneally (i.p.) with water (control, CTRL), MET (200 µg/g), SRL (5 µg/g), or MET (200 µg/g) +SRL (5 µg/g) over a period of one month. We evaluated the body weight, food consumption rate, random blood glucose (BG), insulin levels, serum biochemistry parameters (ALT, Albumin, BUN, Creatinine), and histomorphology in all groups using standardized techniques and assays. All drug-treated groups showed a statistically significant decrease in weight gain compared to the CTRL group, despite normal food intake. Treatment with SRL caused elevated BG and insulin levels, which were restored with SRL + MET combination. Serum biochemical parameters were within the normal range in all the studied groups. SRL+ MET co-treatment decreased liver cellular respiration and increased cellular ATP levels in the liver. In the pancreas, co-treatment resulted in increased cellular respiration and decreased cellular ATP levels. Liver and pancreatic histology were unchanged in all groups. This study showed that co-treatment of SRL with MET alleviates hyperglycemia induced by SRL without any deleterious effects. These results provide initial insights into the potential use of SRL + MET therapy in various settings.

Topics: Adenosine Triphosphate; Animals; Cell Respiration; Glucose; Graft Rejection; Hyperglycemia; Immunosuppressive Agents; Insulins; Metformin; Mice; Mice, Inbred BALB C; Sirolimus

Hyperglycemia has been widely reported to induce vascular senescence. We have previously demonstrated that angiotensin II (Ang II) could promote brain vascular smooth muscle cell (VSMC) senescence, and its type 2 (AT2) receptor deletion could enhance VSMC senescence. Therefore, we examined the possible cross-talk between Ang II and hyperglycemia on VSMC senescence, and the roles of AT2 receptor agonist, compound 21 (C21) on it.. Aortic VSMCs were prepared from adult male mice and stimulated with Ang II and/or high glucose (Glu) and/or C21 and/or an autophagy inhibitor, 3-methyladenine (3-MA), and/or an autophagy agonist, rapamycin (RAP) for the indicated times. Cellular senescence, oxidative stress, and protein expressions were evaluated.. Combination treatment with Ang II and Glu synergistically increased the proportion of VSMC senescent area compared with control group and each treatment alone, which was almost completely attenuated by C21 treatment. Moreover, combination treatment induced significant changes in the levels of superoxide anion, the expressions of p21 and pRb, and the ratio of LC3B II/I expression, which were also significantly attenuated by C21 treatment. The proportion of VSMC senescent area and the levels of superoxide anion by combination treatment were increased after 3-MA treatment, and the proportion of senescent area and the expressions of p21 and pRb were decreased after RAP treatment, both of which were further attenuated by C21 treatment.. Ang II and hyperglycemia synergistically promoted VSMC senescence, at least partly through the participation by autophagy, oxidative stress, and p21-pRb pathway, which could be inhibited by C21.

Topics: Angiotensin II; Animals; Carrier Proteins; Cells, Cultured; Cellular Senescence; Glucose; Hyperglycemia; Imidazoles; Male; Mice; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; Receptor, Angiotensin, Type 2; Sirolimus; Sulfonamides; Superoxides; Thiophenes

In this study, atypical choroid plexus papilloma was treated with high-dose rapamycin for 17 days preoperatively in an infant. Rapamycin significantly reduced the blood supply to the tumor while reducing the tumor volume, and most of the tumor was resected successfully. However, the infant developed hyperglycemia related to the rapamycin dose, which was effectively controlled by adjusting the dose and applying insulin.

Topics: Choroid Plexus Neoplasms; Glioma; Humans; Hyperglycemia; Infant; Papilloma, Choroid Plexus; Sirolimus

The innate immune kinase TBK1 (TANK-binding kinase 1) responds to microbial-derived signals to initiate responses against viral and bacterial pathogens. More recent work implicates TBK1 in metabolism and tumorigenesis. The kinase mTOR (mechanistic target of rapamycin) integrates diverse environmental cues to control fundamental cellular processes. Our prior work demonstrated in cells that TBK1 phosphorylates mTOR (on S2159) to increase mTORC1 and mTORC2 catalytic activity and signaling. Here we investigate a role for TBK1-mTOR signaling in control of glucose metabolism in vivo. We find that mice with diet-induced obesity (DIO) but not lean mice bearing a whole-body "TBK1-resistant" Mtor S2159A knock-in allele (MtorA/A) display exacerbated hyperglycemia and systemic insulin resistance with no change in energy balance. Mechanistically, Mtor S2159A knock-in in DIO mice reduces mTORC1 and mTORC2 signaling in response to insulin and innate immune agonists, reduces anti-inflammatory gene expression in adipose tissue, and blunts anti-inflammatory macrophage M2 polarization, phenotypes shared by mice with tissue-specific inactivation of TBK1 or mTOR complexes. Tissues from DIO mice display elevated TBK1 activity and mTOR S2159 phosphorylation relative to lean mice. We propose a model whereby obesity-associated signals increase TBK1 activity and mTOR phosphorylation, which boost mTORC1 and mTORC2 signaling in parallel to the insulin pathway, thereby attenuating insulin resistance to improve glycemic control during diet-induced obesity.

Topics: Animals; Glucose; Hyperglycemia; Insulin; Insulin Resistance; Mechanistic Target of Rapamycin Complex 1; Mechanistic Target of Rapamycin Complex 2; Mice; Mice, Obese; Multiprotein Complexes; Obesity; Protein Serine-Threonine Kinases; Sirolimus; TOR Serine-Threonine Kinases

Rapamycin treatment has positive and negative effects on progression of type 2 diabetes (T2D) in a recombinant inbred polygenic mouse model, male NONcNZO10/LtJ (NcZ10). Here, we show that combination treatment with metformin ameliorates negative effects of rapamycin while maintaining its benefits. From 12 to 30 weeks of age, NcZ10 males were fed a control diet or diets supplemented with rapamycin, metformin, or a combination of both. Rapamycin alone reduced weight gain, adiposity, HOMA-IR, and inflammation, and prevented hyperinsulinemia and pre-steatotic hepatic lipidosis, but exacerbated hyperglycemia, hypertriglyceridemia, and pancreatic islet degranulation. Metformin alone reduced hyperinsulinemia and circulating c-reactive protein, but exacerbated nephropathy. Combination treatment retained the benefits of both while preventing many of the deleterious effects. Importantly, the combination treatment reversed effects of rapamycin on markers of hepatic insulin resistance and normalized systemic insulin sensitivity in this inherently insulin-resistant model. In adipose tissue, rapamycin attenuated the expression of genes associated with adipose tissue expansion (Mest, Gpam), inflammation (Itgam, Itgax, Hmox1, Lbp), and cell senescence (Serpine1). In liver, the addition of metformin counteracted rapamycin-induced alterations of G6pc, Ppara, and Ldlr expressions that promote hyperglycemia and hypertriglyceridemia. Both rapamycin and metformin treatment reduced hepatic Fasn expression, potentially preventing lipidosis. These results delineate a state of "insulin signaling restriction" that withdraws endocrine support for further adipogenesis, progression of the metabolic syndrome, and the development of its comorbidities. Our results are relevant for the treatment of T2D, the optimization of current rapamycin-based treatments for posttransplant rejection and various cancers, and for the development of treatments for healthy aging.

Topics: Animals; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 2; Fatty Liver; Hyperglycemia; Hyperinsulinism; Hypertriglyceridemia; Hypoglycemic Agents; Inflammation; Insulin; Insulin Resistance; Male; Metabolic Syndrome; Metformin; Mice; Sirolimus

The objective of this study was to determine if mechanistic target of rapamycin (mTOR) inhibition with or without AMP-activated protein kinase (AMPK) activation can protect against primary, age-related OA.. Dunkin-Hartley guinea pigs develop mild primary OA pathology by 5 months of age that progresses to moderate OA by 8 months of age. At 5 months, guinea pigs served as young control (n = 3) or were fed either a control diet (n = 8), a diet enriched with the mTOR-inhibitor rapamycin (Rap, 14 ppm, n = 8), or Rap with the AMPK-activator metformin (Rap+Met, 1000 ppm, n = 8) for 12 weeks. Knee joints were evaluated by OARSI scoring, micro-computed tomography, and immunohistochemistry. Glenohumeral articular cartilage was collected for western blotting.. Rap- and Rap+Met-treated guinea pigs displayed lower body weight than control. Rap and Rap+Met inhibited articular cartilage mTORC1 but not mTORC2 signaling. Rap+Met, but not Rap alone, stimulated AMPK. Despite lower body weight and articular cartilage mTORC1 inhibition, Rap- and Rap+Met-treated guinea pigs had greater OA severity in the medial tibial plateau due to articular cartilage structural damage and/or proteoglycan loss. Rap and Rap+Met increased plasma glucose compared to control. Plasma glucose concentration was positively correlated with proteoglycan loss, suggesting hyperglycemic stress after Rap treatment was related to worsened OA.. This is the first study to show that Rap induced increase in plasma glucose was associated with greater OA severity. Further, articular cartilage mTORC1 inhibition and bodyweight reduction by dietary Rap and Rap+Met did not appear to protect against primary OA during the prevailing hyperglycemia.

Topics: Animals; Cartilage, Articular; Guinea Pigs; Hyperglycemia; Osteoarthritis; Sirolimus; X-Ray Microtomography

Determine the impact of the mTOR inhibitor, rapamycin, on the hyperglycemia-induced expression of vascular endothelial growth factor (VEGF) and the production of reactive oxygen species (ROS) in retinal cells. Rats made hyperglycemic for 8 weeks by streptozotocin, as well as control rats, received i.p. rapamycin (1 mg/kg) for 3 days prior to immunostaining of their retinas with anti-VEGF and anti-glial fibrillary acidic protein (GFAP) and measuring retinal protein levels of VEGF and GFAP by Western blotting. In other experiments, flow cytometry analysis of ethidium fluorescence determined intracellular ROS levels in the absence or presence of rapamycin (1 μM) under normoglycemic (5.5 mM) and hyperglycemic (25 mM) conditions in a rat retinal Müller cell line (TR-MUL5) and primary human retinal microvascular endothelial cells (HRMECs). In the diabetic retina, VEGF was elevated and colocalized with the glial marker, GFAP, whose level was also elevated. Treatment with rapamycin inhibited the diabetes-induced VEGF and GFAP increases. We also found that raising extracellular glucose from 5.5 mM to 25 mM resulted in significant rapamycin-sensitive increases in the ROS levels of TR-MUL5 cells and HRMECs. In rat retina, rapamycin attenuates the diabetes-induced VEGF overexpression, and in cultured Müller cells and HRMECs, inhibits the hyperglycemia-induced boost ROS.

Topics: Animals; Blotting, Western; Cell Line; Cells, Cultured; Diabetes Mellitus, Experimental; Endothelial Cells; Ependymoglial Cells; Glial Fibrillary Acidic Protein; Humans; Hyperglycemia; Injections, Intraperitoneal; Male; Rats, Wistar; Reactive Oxygen Species; Retina; Sirolimus; TOR Serine-Threonine Kinases; Vascular Endothelial Growth Factor A

For patients with pure red cell aplasia (PRCA), cyclosporine (CsA) is the first line therapy. Occasionally, some patients who suffer from renal insufficiency cannot tolerate CsA. To explore the efficacy and tolerance of sirolimus treatment for those patients, twelve PRCA patients with renal insufficiency from May 2014 to May 2018 in Peking Union Medical College Hospital were enrolled, treated with sirolimus, and followed up at the median time of 16 (10-50) months. Eleven patients (91.7%) responded to sirolimus, with 58.3% complete response (CR) and 41.7% partial response (PR). The median time to achieve the optimum effect was 4 (1-7) months. The serum creatinine level remained stable or even reduced during the treatment period for eleven patients. Seven patients (58.3%) reported adverse events during sirolimus therapy, including increased blood glucose, infection, skin rash, elevated triglyceride or total cholesterol, and elevated serum creatinine compared with baseline. No treatment-related death was noticed during the follow-up time. Three patients relapsed with an overall response rate of 75.0% at 1 year. These results suggested that sirolimus was effective and tolerable for patients with PRCA complicated with renal insufficiency.

Topics: Adult; Aged; Aged, 80 and over; Creatinine; Cyclosporine; Drug Eruptions; Drug Evaluation; Drug Substitution; Female; Humans; Hyperglycemia; Hypertriglyceridemia; Immunosuppressive Agents; Male; Middle Aged; Recurrence; Red-Cell Aplasia, Pure; Remission Induction; Renal Insufficiency; Retrospective Studies; Sirolimus; Treatment Outcome

Pre-ischemic hyperglycemia increases the occurrence of post-ischemic seizures both in experimental and clinical settings. The underlying mechanisms are not fully delineated; however, activation of mammalian target of rapamycin (mTOR) has been shown to be engaged in the pathogenesis of epilepsy, in which seizures are a regular occurrence. Therefore, we wanted to explore specifically the capacity of an mTOR inhibitor, rapamycin, in preventing post-ischemic seizures in hyperglycemic rats and to explore the underlying molecular mechanisms. The results showed that none of the rats in the sham control, EG ischemic, or within 3 h of I/R in hyperglycemic ischemic groups experienced seizures. Generalized tonic-clonic seizures were observed in all 8/8 of hyperglycemic ischemic rats at 16 h of I/R. Treatment with rapamycin successfully blocked post-ischemic seizures in 7/8 hyperglycemic ischemic animals. Rapamycin also lessened the neuronal death extraordinarily in hyperglycemic ischemic animals as revealed by histopathological studies. Protein analysis revealed that transient ischemia resulted in increases in p-mTOR and p-S6, especially in the hippocampi of the hyperglycemic ischemic rats. Rapamycin treatment completely blocked mTOR activation. Furthermore, hyperglycemic ischemia induced a much prominent rise of p-ERK1/2 both in the cortex and the hippocampi compared with EG counterparts; whereas rapamycin suppressed it. We conclude that the development of post-ischemic seizures in the hyperglycemic animals may be associated with activations of mTOR and ERK1/2 pathways and that rapamycin treatment inhibited the post-ischemic seizures effectively by suppressing the mTOR and ERK1/2 signaling.

Topics: Animals; Anticonvulsants; Brain Ischemia; Cell Death; Cerebral Cortex; Cytosol; Disease Models, Animal; Hippocampus; Hyperglycemia; Male; MAP Kinase Signaling System; Neurons; Phosphorylation; Rats; Rats, Wistar; Seizures; Signal Transduction; Sirolimus; TOR Serine-Threonine Kinases

Identifying regulatory mechanisms that influence inflammation in metabolic tissues is critical for developing novel metabolic disease treatments. Here, we investigated the role of microRNA-146a (miR-146a) during diet-induced obesity in mice. miR-146a is reduced in obese and type 2 diabetic patients and our results reveal that miR-146a-/- mice fed a high-fat diet (HFD) have exaggerated weight gain, increased adiposity, hepatosteatosis, and dysregulated blood glucose levels compared to wild-type controls. Pro-inflammatory genes and NF-κB activation increase in miR-146a-/- mice, indicating a role for this miRNA in regulating inflammatory pathways. RNA-sequencing of adipose tissue macrophages demonstrated a role for miR-146a in regulating both inflammation and cellular metabolism, including the mTOR pathway, during obesity. Further, we demonstrate that miR-146a regulates inflammation, cellular respiration and glycolysis in macrophages through a mechanism involving its direct target Traf6. Finally, we found that administration of rapamycin, an inhibitor of mTOR, was able to rescue the obesity phenotype in miR-146a-/- mice. Altogether, our study provides evidence that miR-146a represses inflammation and diet-induced obesity and regulates metabolic processes at the cellular and organismal levels, demonstrating how the combination of diet and miRNA genetics influences obesity and diabetic phenotypes.

Topics: Animals; Blood Glucose; Diet, High-Fat; Disease Models, Animal; Female; Gene Expression; Humans; Hyperglycemia; Inflammation; Insulin; Intra-Abdominal Fat; Macrophages; Male; Metabolic Diseases; Mice; Mice, Inbred C57BL; Mice, Knockout; MicroRNAs; NF-kappa B; Obesity; Proto-Oncogene Proteins c-akt; Sirolimus; TOR Serine-Threonine Kinases; Weight Gain

Hyperglycemia is known to exacerbate neuronal death resulted from cerebral ischemia. The mechanisms are not fully understood. The mammalian target of rapamycin (mTOR) pathway regulates cell growth, division and apoptosis. Recent studies suggest that activation of mTOR may mediate ischemic brain damage. The objective of the present experiment is to explore whether mTOR mediates ischemic brain damage in acute hyperglycemic animals. Rats were subjected to 10 min of forebrain ischemia under euglycemic, hyperglycemic and rapamycin-treated hyperglycemic conditions. The rat brain samples were collected from the cortex and hippocampi after 3h and 16h of reperfusion. The results showed that hyperglycemia significantly increased neuronal death in the cortex and hippocampus and the exacerbation effect of hyperglycemia was associated with further activation of mTOR under control and/or ischemic conditions. Inhibition of mTOR with rapamycin ameliorated the damage and suppressed hyperglycemia-elevated p-MTOR, p-P70S6K and p-S6. In addition, hyperglycemia

Topics: Animals; Brain Ischemia; Hyperglycemia; Immunosuppressive Agents; Male; Random Allocation; Rats; Rats, Wistar; Signal Transduction; Sirolimus; TOR Serine-Threonine Kinases

Solid organ transplantation (SOT) outcomes have continued to improve, although long-term use of immunosuppressants can lead to complications such as diabetes, compromising post-transplant outcomes. In this study, we have characterized the intestinal microbiome (IM) composition at the metagenomic level in the context of hyperglycemia induced by immunosuppressants. Sprague-Dawley rats were subjected to doses of tacrolimus and sirolimus that reliably induce hyperglycemia and an insulin-resistant state. Subsequent exposure to probiotics resulted in reversal of hyperglycemia. 16S rRNA and metagenomic sequencing of stool were done to identify the bacterial genes and pathways enriched in immunosuppression. Bacterial diversity was significantly decreased in sirolimus-treated rats, with 9 taxa significantly less present in both immunosuppression groups: Roseburia, Oscillospira, Mollicutes, Rothia, Micrococcaceae, Actinomycetales and Staphylococcus. Following probiotics, these changes were reversed to baseline. At the metagenomic level, the balance of metabolism was shifted towards the catabolic side with an increase of genes involved in sucrose degradation, similar to diabetes. Conversely, the control rats had greater abundance of anabolic processes and genes involved in starch degradation. Immunosuppression leads to a more catabolic microbial profile, which may influence development of diabetes after SOT. Modulation of the microbiome with probiotics may help in minimizing adverse long-term effects of immunosuppression.

Topics: Animals; Computational Biology; Diabetes Mellitus; Gastrointestinal Microbiome; Gene Ontology; Humans; Hyperglycemia; Immunosuppression Therapy; Immunosuppressive Agents; Insulin Resistance; Male; Metagenome; Metagenomics; Rats; RNA, Ribosomal, 16S; Sirolimus; Systems Biology; Tacrolimus; Transplantation

The guideline for the management of new-onset diabetes after transplantation recommends metformin (MET) as a first-line drug, and addition of a second-line drug is needed to better control of hyperglycemia. We tested the effect of addition of a dipeptidyl peptidase IV (DPP IV) inhibitor to MET on sirolimus (SRL)-induced diabetes mellitus (DM). In animal model of SRL-induced DM, MET treatment improved pancreatic islet function (blood glucose level and insulin secretion) and attenuated oxidative stress and apoptotic cell death. Addition of a DPP IV inhibitor to MET improved these parameters more than MET alone. An in vitro study showed that SRL treatment increased pancreas beta cell death and production of reactive oxygen species (ROS), and pretreatment of ROS inhibitor, or p38MAPK inhibitor effectively decreased SRL-induced islet cell death. Exendin-4 (EXD), a substrate of DPP IV or MET significantly improved cell viability and decreased ROS production compared with SRL treatment, and combined treatment with the 2 drugs improved both parameters. At the subcellular level, impaired mitochondrial respiration by SRL were partially improved by MET or EXD and much improved further after addition of EXD to MET. Our data suggest that addition of a DPP IV inhibitor to MET decreases SRL-induced oxidative stress and improves mitochondrial respiration. This finding provides a rationale for the combined use of a DPP IV inhibitor and MET in treating SRL-induced DM.

Topics: Animals; Apoptosis; Cell Survival; Diabetes Mellitus, Experimental; Dipeptidyl-Peptidase IV Inhibitors; Disease Models, Animal; Drug Therapy, Combination; Exenatide; Hyperglycemia; Islets of Langerhans; Male; Metformin; Mitochondria; Oxidative Stress; Peptides; Piperidones; Pyrimidines; Rats, Sprague-Dawley; Reactive Oxygen Species; Sirolimus; Venoms

Hyperglycemia following solid organ transplant is common among patients without pre-existing diabetes mellitus (DM). Post-transplant hyperglycemia can occur once or multiple times, which if continued, causes new-onset diabetes after transplantation (NODAT).. To study if the first and recurrent incidence of hyperglycemia are affected differently by immunosuppressive regimens, demographic and medical-related risk factors, and inpatient hyperglycemic conditions (i.e., an emphasis on the time course of post-transplant complications).. We conducted a retrospective analysis of 407 patients who underwent kidney transplantation at Mayo Clinic Arizona. Among these, there were 292 patients with no signs of DM prior to transplant. For this category of patients, we evaluated the impact of (1) immunosuppressive drugs (e.g., tacrolimus, sirolimus, and steroid), (2) demographic and medical-related risk factors, and (3) inpatient hyperglycemic conditions on the first and recurrent incidence of hyperglycemia in one year post-transplant. We employed two versions of Cox regression analyses: (1) a time-dependent model to analyze the recurrent cases of hyperglycemia and (2) a time-independent model to analyze the first incidence of hyperglycemia.. Age (P = 0.018), HDL cholesterol (P = 0.010), and the average trough level of tacrolimus (P<0.0001) are significant risk factors associated with the first incidence of hyperglycemia, while age (P<0.0001), non-White race (P = 0.002), BMI (P = 0.002), HDL cholesterol (P = 0.003), uric acid (P = 0.012), and using steroid (P = 0.007) are the significant risk factors for the recurrent cases of hyperglycemia.. This study draws attention to the importance of analyzing the risk factors associated with a disease (specially a chronic one) with respect to both its first and recurrent incidence, as well as carefully differentiating these two perspectives: a fact that is currently overlooked in the literature.

Topics: Cohort Studies; Female; Humans; Hyperglycemia; Immunosuppressive Agents; Kidney Transplantation; Male; Middle Aged; Recurrence; Risk Factors; Sirolimus; Steroids; Tacrolimus; Transplant Recipients

Although the contribution of the immunosuppressants tacrolimus (TAC) and sirolimus (SIR) to the development of posttransplant diabetes mellitus (PTDM) are being increasingly recognized, the mechanisms of immunosuppressant-induced hyperglycemia are unclear. SIR induces insulin resistance predominantly, but is associated with β-cell dysfunction in rodents. TAC affects islet function but is associated with worsening insulin sensitivity in a few, and improvement in some, clinical studies. We sought to clarify the contributions of TAC and SIR to insulin resistance and islet function. Four groups of male and female Sprague-Dawley rats received TAC, SIR, TAC and SIR, or control for 2 weeks. All rats were administered an oral glucose challenge at the end of treatment. Half the groups were sacrificed 10 minutes after administration of regular insulin whereas the other half did not receive insulin before sacrifice. Liver, pancreas, fat, and muscle were harvested subsequently. Quantification of Western blots revealed that SIR and TAC plus SIR suppressed the phospho-Akt (pAkt)-to-Akt ratios in liver, muscle, and fat compared with control, regardless of sex. TAC alone did not impair the pAkt-to-Akt ratios in any of the tissues in male and female rats. β-Cell mass was reduced significantly after TAC treatment in male rats. SIR did not affect β-cell mass, regardless of sex. Our study demonstrated very clearly that SIR impairs insulin signaling, without any effect on β-cell mass, and TAC does not impair insulin signaling but reduces β-cell mass. Our efforts are key to understanding the mechanisms of immunosuppressant-induced hyperglycemia and to tailoring treatments for PTDM.

Topics: Adipose Tissue; Animals; Female; Hyperglycemia; Immunosuppressive Agents; Insulin; Liver; Male; Mice; Mice, Inbred C57BL; Pancreas; Rats; Rats, Sprague-Dawley; Sex Factors; Signal Transduction; Sirolimus; Tacrolimus; Transplants

Mammalian target of rapamycin (mTOR) is involved in insulin resistance (IR) and diabetic retinopathy. In retinal pigment epithelial (RPE) cells, insulin activates the mTOR pathway, inducing hypoxia-inducible factor-1α (HIF-1α) and HIF-dependent transcription in serum-free minimum essential medium Eagle (MEM). Serendipitously, we found that insulin failed to induce the HIF-1α-dependent response, when RPE cells were cultured in Dulbecco's modification of Eagle's medium (DMEM). Whereas concentration of glucose in MEM corresponds to normal glucose levels in blood (5.5 mM), its concentration in DMEM corresponds to severe diabetic hyperglycemia (25 mM). Addition of glucose to MEM also caused IR. Glucose-mediated IR was characterized by basal activation of mTORC1 and its poor inducibility by insulin. Basal levels of phosphorylated S6 kinase (S6K), S6 and insulin receptor substrate 1 (IRS1) S635/639 were high, whereas their inducibilities were decreased. Insulin-induced Akt phosphorylation was decreased and restored by rapamycin and an inhibitor of S6K. IR was associated with de-phosphorylation of IRS1 at S1011, which was reversed by rapamycin. Both short (16-40 h) and chronic (2 weeks) treatment with rapamycin reversed IR. Furthermore, rapamycin did not impair Akt activation in RPE cells cultured in normoglycemic media. In contrast, Torin 1 blocked Akt activation by insulin. We conclude that by activating mTOR/S6K glucose causes feedback IR, preventable by rapamycin. Rapamycin does not cause IR in RPE cells regardless of the duration of treatment. We confirmed that rapamycin also did not impair phosphorylation of Akt at T308 and S473 in normal myoblast C2C12 cells. Our work provides insights in glucose-induced IR and suggests therapeutic approaches to treat patients with IR and severe hyperglycemia and to prevent diabetic complications such as retinopathy. Also our results prompt to reconsider physiological relevance of numerous data and paradigms on IR given that most cell lines are cultured with grossly super-physiological levels of glucose.

Topics: Animals; Cell Line; Enzyme Activation; Glucose; Hyperglycemia; Hypoglycemic Agents; Insulin; Insulin Receptor Substrate Proteins; Insulin Resistance; Mechanistic Target of Rapamycin Complex 1; Mice; Multiprotein Complexes; Myoblasts, Skeletal; Oligonucleotides; Phosphorylation; Protein Kinase Inhibitors; Proto-Oncogene Proteins c-akt; Retinal Pigment Epithelium; Ribosomal Protein S6 Kinases; Signal Transduction; Sirolimus; Time Factors; TOR Serine-Threonine Kinases; Transfection

Preclinical evaluation of the vascular response of drug-eluting stents is limited especially in the setting of diabetes mellitus preventing the evaluation of changes in drug-eluting stent design and eluted drugs after clinical use.. Cultured human aortic endothelial cells were used to assess the differences between sirolimus and its analog, everolimus, in the setting of hyperglycemia on various cellular functions necessary for endothelial recovery. A diabetic rabbit model of iliac artery stenting was used to compare histological and morphometric characteristics of the vascular response to everolimus-eluting, sirolimus-eluting, and bare metal stent placement. Under hyperglycemic conditions, sirolimus impaired human aortic endothelial cell barrier function, migration, and proliferation to a greater degree compared with everolimus. In our in vivo model of diabetes mellitus, endothelialization at 28 days was significantly lower and endothelial integrity was impaired in sirolimus-eluting stent compared with both everolimus-eluting and bare metal stents. Neointimal area, uncovered struts, and fibrin deposition were significantly higher in sirolimus-eluting compared with everolimus-eluting and bare metal stents.. Use of everolimus-eluting stent results in improved vascular response in our preclinical models of diabetes mellitus.

Topics: Animals; Aorta; Cell Movement; Cells, Cultured; Diabetes Mellitus; Disease Models, Animal; Drug-Eluting Stents; Endothelial Cells; Everolimus; Fibrin; Humans; Hyperglycemia; Iliac Artery; Male; Neointima; Rabbits; Sirolimus

Everolimus is an orally administered anti-cancer drug that inhibits the mammalian target of rapamycin (mTOR) signal transduction route. Use of everolimus may be associated with insulin resistance, manifesting in impaired glucose tolerance or hyperglycaemia.. A 74-year-old female patient with a locally recurrent breast cancer developed hyperglycaemia, which started 2 weeks after the initiation of treatment with everolimus 10 mg once daily. Metformin and insulin were administered to restore normoglycaemia.. At the initiation of treatment with an mTOR inhibitor such as everolimus the treating physician should be aware of the occurrence of hyperglycaemia. Metformin is then the medicine of first choice.

Topics: Aged; Antineoplastic Agents; Breast Neoplasms; Everolimus; Female; Humans; Hyperglycemia; Hypoglycemic Agents; Metformin; Neoplasm Recurrence, Local; Sirolimus; TOR Serine-Threonine Kinases

Our aim was to investigate the potential role of TOR (target of rapamycin) signaling pathway in the regulation of hepatic glucose metabolism in rainbow trout. Fasted fish were first treated with a single intraperitoneal injection of rapamycin or vehicle and then submitted to a second intraperitoneal administration of glucose 4 h later. Our results revealed that intraperitoneal administration of glucose induced hyperglycemia for both vehicle and rapamycin treatments, which peaked at 2 h. Plasma glucose level in vehicle-treated fish was significantly higher than in rapamycin-treated fish at 8 and 17 h, whereas it remained at the basal level in rapamycin-treated fish. Glucose administration significantly enhanced the phosphorylation of Akt and ribosomal protein S6 kinase (S6K1) in vehicle-treated fish, while rapamycin completely abolished the activation of S6K1 in rapamycin-treated fish, without inhibiting the phosphorylation of Akt on Thr-308 or Ser-473. Despite the lack of significant variation in phosphoenolpyruvate carboxykinase mRNA abundance, mRNA abundance for glucokinase (GK), glucose 6-phosphatase (G6Pase) I and II, and fructose 1,6-bisphosphatase (FBPase) was reduced by rapamycin 17 h after glucose administration. The inhibition effect of rapamycin on GK and FBPase was further substantiated at the activity level. The suppression of GK gene expression and activity by rapamycin provided the first in vivo evidence in fish that glucose regulates hepatic GK gene expression and activity through a TORC1-dependent manner. Unlike in mammals, we observed that acute rapamycin treatment improved glucose tolerance through the inhibition of hepatic gluconeogenesis in rainbow trout.

Topics: Animals; Blood Glucose; Disease Models, Animal; Fish Proteins; Fructose-Bisphosphatase; Glucokinase; Gluconeogenesis; Hyperglycemia; Liver; Mechanistic Target of Rapamycin Complex 1; Multiprotein Complexes; Oncorhynchus mykiss; Phosphorylation; Proto-Oncogene Proteins c-akt; Ribosomal Protein S6 Kinases, 70-kDa; RNA, Messenger; Signal Transduction; Sirolimus; Time Factors; TOR Serine-Threonine Kinases

While rapamycin treatment has been reported to have a putatively negative effect on glucose homeostasis in mammals, it has not been tested in polygenic models of type 2 diabetes. One such mouse model, NONcNZO10/LtJ, was treated chronically with rapamycin (14 ppm encapsulated in diet) and monitored for the development of diabetes. As expected, rapamycin treatment accelerated the onset and severity of hyperglycemia. However, development of nephropathy was ameliorated, as both glomerulonephritis and IgG deposition in the subendothelial tuft were markedly reduced. Insulin production and secretion appeared to be inhibited, suppressing the developing hyperinsulinemia present in untreated controls. Rapamycin treatment also reduced body weight gain. Thus, rapamycin reduced some of the complications of diabetes despite elevating hyperglycemia. These results suggest that multiple factors must be evaluated when assessing the benefit vs. hazard of rapamycin treatment in patients that have overt, or are at risk for, type 2 diabetes. Testing of rapamycin in combination with insulin sensitizers is warranted, as such compounds may ameliorate the putative negative effects of rapamycin in the type 2 diabetes environment.

Topics: Animals; Blood Glucose; Diabetes Mellitus, Type 2; Diabetic Nephropathies; Disease Models, Animal; Female; Humans; Hyperglycemia; Hyperinsulinism; Insulin; Insulin Secretion; Male; Mice; Sirolimus

Non-Fc-binding Anti CD3 antibody has proven successful in reverting diabetes in the non-obese diabetes mouse model of type 1 diabetes and limited efficacy has been observed in human clinical trials. We hypothesized that addition of rapamycin, an mTOR inhibitor capable of inducing operational tolerance in allogeneic bone marrow transplantation, would result in improved diabetes reversal rates and overall glycemia.. Seventy hyperglycemic non-obese diabetic mice were randomized to either a single injection of anti CD3 alone or a single injection of anti CD3 followed by 14 days of intra-peritoneal rapamycin. Mice were monitored for hyperglycemia and metabolic control.. Mice treated with the combination of anti CD3 and rapamycin had similar rates of diabetes reversal compared to anti CD3 alone (25/35 vs. 22/35). Mice treated with anti CD3 plus rapamycin had a significant improvement in glycemia control as exhibited by lower blood glucose levels in response to an intra-peritoneal glucose challenge; average peak blood glucose levels 30 min post intra-peritoneal injection of 2 gr/kg glucose were 6.9 mmol/L in the anti CD3 plus rapamycin group vs. 10 mmo/L in the anti CD3 alone (P<0.05).. The addition of rapamycin to anti CD3 results in significant improvement in glycaemia control in diabetic NOD mice.

Topics: Animals; Antibodies; CD3 Complex; Diabetes Mellitus, Experimental; Female; Humans; Hyperglycemia; Mice; Mice, Inbred NOD; Sirolimus

The aim of the study was to assess the safety and efficacy of everolimus therapy for advanced renal cell carcinoma in Japanese patients receiving real-world care.. Patients who had been treated with everolimus for advanced renal cell carcinoma at 39 Japanese medical centers between January 2010 and November 2011 were retrospectively investigated to assess adverse events and the time to treatment failure.. A total of 180 patients were identified. Their median age was 65 years (range 23-93). The median time to treatment failure was 2.9 months (95% confidence interval 2.4-3.4). The median time to treatment failure was significantly longer in patients with dose modification (4.2 months; 95% confidence interval 3.4-5.0) than in patients without dose modification (1.7 months; 95% confidence interval 1.0-2.3; P < 0.01) after experiencing adverse events. Stomatitis (44%) was the most frequent adverse event, followed by thrombocytopenia (31%), anemia (22%), interstitial pneumonia (22%) and hyperglycemia (17%). Interstitial pneumonia was the most frequent cause of discontinuation in patients who discontinued everolimus due to intolerability regardless of the dose modification status. None of the patients with dose modification of everolimus discontinued everolimus due to thrombocytopenia or leukopenia.. The adverse event profile of everolimus may differ between Japanese and Caucasian patients. Dose modification of everolimus might be associated with longer treatment duration in patients with advanced renal cell carcinoma. Further studies are required to clarify this association. Interstitial pneumonia may be difficult to overcome by dose modification.

Topics: Adult; Aged; Aged, 80 and over; Antineoplastic Agents; Carcinoma, Renal Cell; Drug Administration Schedule; Everolimus; Female; Humans; Hyperglycemia; Japan; Kaplan-Meier Estimate; Kidney Neoplasms; Lung Diseases, Interstitial; Male; Middle Aged; Retrospective Studies; Sirolimus; Stomatitis; Thrombocytopenia; Treatment Outcome

Increasing evidence implicates mitochondrial dysfunction as an early, important event in the pathogenesis of critical illness-induced multiple organ failure. We previously demonstrated that prevention of hyperglycemia limits damage to mitochondria in vital organs, thereby reducing morbidity and mortality. We now hypothesize that inadequate activation of mitochondrial repair processes (clearance of damaged mitochondria by autophagy, mitochondrial fusion/fission, and biogenesis) may contribute to accumulation of mitochondrial damage, persistence of organ failure, and adverse outcome of critical illness.. Prospective, randomized studies in a critically ill rabbit model.. University laboratory.. Three-month-old male rabbits.. We studied whether vital organ mitochondrial repair pathways are differentially affected in surviving and nonsurviving hyperglycemic critically ill animals in relation to mitochondrial and organ damage. Next, we investigated the impact of preventing hyperglycemia over time and of administering rapamycin as an autophagy activator.. In both liver and kidney of hyperglycemic critically ill rabbits, we observed signs of insufficient autophagy, including accumulation of p62 and a concomitant decrease in the microtubule-associated protein light-chain-3-II/microtubule-associated protein light-chain-3-I ratio. The phenotype of insufficient autophagy was more pronounced in nonsurviving than in surviving animals. Molecular markers of insufficient autophagy correlated with impaired mitochondrial function and more severe organ damage. In contrast, key players in mitochondrial fusion/fission or biogenesis were not significantly different regarding survival status. Therefore, we focused on autophagy to study the impact of preventing hyperglycemia. Both after 3 and 7 days of illness, autophagy was better preserved in normoglycemic than in hyperglycemic rabbits, which correlated with improved mitochondrial function and less organ damage. Stimulation of autophagy in kidney with rapamycin correlated with protection of renal function.. Our findings put forward insufficient autophagy as a potentially important contributor to mitochondrial and organ damage in critical illness and open perspectives for therapies that activate autophagy during critical illness.

Topics: Animals; Autophagy; Biomarkers; Critical Illness; Hyperglycemia; Immunosuppressive Agents; Kidney; Male; Microtubule-Associated Proteins; Mitochondria, Liver; Mitochondrial Diseases; Mitochondrial Dynamics; Mitophagy; Multiple Organ Failure; Prospective Studies; Rabbits; Random Allocation; Sirolimus; Survival Analysis

Immunosuppressants are an important cause of posttransplantation diabetes mellitus. We have shown that tacrolimus and sirolimus induce hyperglycemia and hyperinsulinemia in normal rats. We hypothesized that metformin, given concurrently with tacrolimus and/or sirolimus, prevents disturbances in glucose and insulin metabolism.. Eight groups (n=6) of normal Sprague-Dawley rats were studied: four groups received tacrolimus, sirolimus, tacrolimus/sirolimus, or control for 14 days, and four more groups received similar treatments along with metformin. Daily glucoses were measured. All rats were administered an oral glucose challenge before sacrifice. Pancreata were analyzed by terminal deoxynucleotide tranferase-mediated dUTP nick-end labeling staining and immunohistochemistry.. Tacrolimus, sirolimus, and tacrolimus/sirolimus impaired glucose tolerance compared to control. Sirolimus and tacrolimus/sirolimus also increased random blood glucose levels. Sirolimus alone resulted in hyperinsulinemia after oral glucose challenge compared to control. In the sirolimus/metformin and tacrolimus/sirolimus/metformin groups, mean daily random glucose was no longer increased, although the response to glucose challenge was still impaired. Metformin decreased pancreatic exocrine and trended to decrease endocrine apoptosis in tacrolimus/sirolimus group and reduced islet insulin content in sirolimus group.. This is the first study to show that metformin can improve immunosuppressant-induced hyperglycemia, when administered concurrently, and reduces exocrine apoptosis (reducing the impact on potential islet progenitor cells).

Topics: Animals; Apoptosis; Biomarkers; Blood Glucose; Disease Models, Animal; Glucose Tolerance Test; Hyperglycemia; Hyperinsulinism; Hypoglycemic Agents; Immunohistochemistry; Immunosuppressive Agents; In Situ Nick-End Labeling; Insulin; Male; Metformin; Pancreas, Exocrine; Rats; Rats, Sprague-Dawley; Sirolimus; Tacrolimus; Time Factors

Rapamycin, a specific inhibitor for mTOR complex 1, is an FDA-approved immunosuppressant for organ transplant. Recent developments have raised the prospect of using rapamycin to treat cancer or diabetes and to delay aging. It is therefore important to assess how rapamycin treatment affects glucose homeostasis. Here, we show that the same rapamycin treatment reported to extend mouse life span significantly impaired glucose homeostasis of aged mice. Moreover, rapamycin treatment of lean C57B/L6 mice reduced glucose-stimulated insulin secretion in vivo and ex vivo as well as the insulin content and beta cell mass of pancreatic islets. Confounding the diminished capacity for insulin release, rapamycin decreased insulin sensitivity. The multitude of rapamycin effects thus all lead to glucose intolerance. As our findings reveal that chronic rapamycin treatment could be diabetogenic, monitoring glucose homeostasis is crucial when using rapamycin as a therapeutic as well as experimental reagent.

Topics: Aging; Animals; Cell Proliferation; Dose-Response Relationship, Drug; Glucose; Glucose Intolerance; Homeostasis; Hyperglycemia; Injections, Intraperitoneal; Insulin; Insulin Resistance; Insulin Secretion; Insulin-Secreting Cells; Islets of Langerhans; Male; Mice; Mice, Inbred C57BL; Organ Size; Signal Transduction; Sirolimus

The mTOR deregulation has a role in chronic kidney disease including diabetic nephropathy. SIRT1 is an important participant in renal cytoprotective responses to aging and stress. However, whether both mTOR and SIRT1 are involved in high glucose-inducing mesangial cells (MCs) senescence still remains to be explored. Hence we investigate the potential functional interrelationship between these two proteins in high glucose-inducing MCs senescence. High glucose increased mTOR expression and activity, but decreased SIRT1 expression and activity. The level of mTOR was increased significantly, while the SIRT1 expression and activity was declined significantly with serial cell culture passage. The siRNA-SIRT1 and nicotinamide promoted MCs senescence. NAD or resveratrol arrested high glucose-inducing MCs senescence. Meanwhile, the effects of NAD or resveratrol on high glucose-inducing MCs senescence were also completely blocked by SiRNA-SIRT1. Rapamycin arrested MCs senescence induced by high glucose and prevented MCs senescence with serial cell culture passage, and meanwhile increased the SIRT1 expression and activity. Moreover, the effects of rapamycin on MCs senescence induced by high glucose were also completely blocked by treating cells with niacinamide or siRNA-SIRT1. These findings provide support for the hypothesis that SIRT1 is required for the effects of rapamycin on high glucose-inducing MCs senescence.

Topics: Animals; Cells, Cultured; Cellular Senescence; Enzyme Inhibitors; Gene Silencing; Hyperglycemia; Male; Mesangial Cells; Niacinamide; Rats; Rats, Wistar; Resveratrol; Sirolimus; Sirtuin 1; Stilbenes; TOR Serine-Threonine Kinases; Vitamin B Complex

In type II diabetes (T2DM), there is a deficit in β-cells, increased β-cell apoptosis and formation of intracellular membrane-permeant oligomers of islet amyloid polypeptide (IAPP). Human-IAPP (h-IAPP) is an amyloidogenic protein co-expressed with insulin by β-cells. IAPP expression is increased with obesity, the major risk factor for T2DM. In this study we report that increased expression of human-IAPP led to impaired autophagy, due at least in part to the disruption of lysosome-dependent degradation. This action of IAPP to alter lysosomal clearance in vivo depends on its propensity to form toxic oligomers and is independent of the confounding effect of hyperglycemia. We report that the scaffold protein p62 that delivers polyubiquitinated proteins to autophagy may have a protective role against human-IAPP-induced apoptosis, apparently by sequestrating protein targets for degradation. Finally, we found that inhibition of lysosomal degradation increases vulnerability of β-cells to h-IAPP-induced toxicity and, conversely, stimulation of autophagy protects β-cells from h-IAPP-induced apoptosis. Collectively, these data imply an important role for the p62/autophagy/lysosomal degradation system in protection against toxic oligomer-induced apoptosis.

Topics: Adaptor Proteins, Signal Transducing; Animals; Apoptosis; Autophagy; Cell Line; Heat-Shock Proteins; Hyperglycemia; Inclusion Bodies; Insulin-Secreting Cells; Islet Amyloid Polypeptide; Lysosomes; Mice; Obesity; Phagosomes; Protective Agents; Protein Processing, Post-Translational; Protein Structure, Quaternary; Rats; RNA, Small Interfering; Sequestosome-1 Protein; Signal Transduction; Sirolimus

Immunosuppression medications contribute to posttransplant diabetes mellitus in patients and can cause insulin resistance in male rats. Tacrolimus (TAC)-sirolimus (SIR) immunosuppression is also associated with appearance of ovarian cysts in transplant patients. Because insulin resistance is observed in patients with polycystic ovary syndrome, we hypothesized that TAC or SIR may induce reproductive abnormalities.. We monitored estrus cycles of adult female rats treated daily with TAC, SIR, and combination of TAC-SIR, or diluent (control) for 4 weeks. Animals were then challenged with oral glucose to determine their glucose and insulin responses, killed, and their blood and tissues, including ovaries and uteri harvested.. TAC and TAC-SIR treatments increased mean random glucose concentrations (P<0.05). TAC, SIR, and TAC-SIR treatments also increased the glucose response to oral glucose challenge (P<0.05). The insulin response to glucose was significantly higher in rats treated with SIR compared with TAC (P<0.05). TAC, SIR and TAC-SIR treatments reduced number of estrus cycles (P<0.05). The ovaries were smaller after SIR and TAC-SIR treatment compared with controls. The TAC and TAC-SIR treatment groups had fewer preovulatory follicles. Corpora lutea were present in all groups. Ovarian aromatase expression was reduced in the SIR and TAC-SIR treatment groups. A significant (P<0.05) reduction in uterine size was observed in all treatment groups when compared with controls.. In a model of immunosuppressant-induced hyperglycemia, both TAC and SIR induced reproductive abnormalities in adult female rats, likely through different mechanisms.

Topics: Animals; Aromatase; Blood Glucose; Estrus; Female; Gene Expression Regulation, Enzymologic; Glucose; Hyperglycemia; Immunosuppressive Agents; Insulin Resistance; Ovary; Phenotype; Polycystic Ovary Syndrome; Rats; Rats, Sprague-Dawley; Sirolimus; Tacrolimus; Uterus

The cellular and molecular mechanisms and safety after drug-eluting stent (DES) implantation in diabetic patients are still poorly understood; therefore, in this study, we evaluated the pathologic responses of the sirolimus-eluting stent (SES) or paclitaxel-eluting stent (PES) in a type I diabetes mellitus (DM) rat model.. The type I DM rat model was manipulated by intra-peritoneal streptozotocin injection. Two weeks later, DES was implanted in the aorta of rats with hyperglycemia or not as a control. Four weeks after DES implantation, the stented aorta was isolated and histomorphometric analysis was performed.. On histomorphometric analysis, increased thrombus, inflammatory cell infiltration, and neointimal hyperplasia (NIH) without change of the smooth muscle cell number after DES implantation were observed in DM rats compared with non-DM (NDM) rats. Furthermore, delayed coverage of mature endothelial cells defined as a von Willebrand factor expression and increased immature endothelial cells as a c-kit expression after DES implantation were observed in DM rats compared with NDM rats. Increased fibrin deposition and decreased hyaluronic acid accumulation at NIH after DES implantation were also observed in DM rats compared with NDM rats.. In conclusion, the main mechanism of restenosis after DES implantation under hyperglycemic conditions was initial thrombus with changes of the extracellular matrix rather than SMC proliferation. These results provided a therapeutic clue for the selection of DES and application of combination therapy using anti-thrombotic and anti-inflammatory drugs in diabetic patients.

Topics: Animals; Anti-Inflammatory Agents; Aorta; Body Weight; Coronary Restenosis; Diabetes Mellitus, Type 1; Disease Models, Animal; Drug-Eluting Stents; Fibrin; Humans; Hyaluronic Acid; Hyperglycemia; Inflammation; Male; Paclitaxel; Rats; Rats, Sprague-Dawley; Sirolimus; Thrombosis

The ability of supplemental islet infusions (SII) to restore insulin independence in islet transplant recipients with graft dysfunction has been attributed to the coadministration of exenatide. However, improving islet transplant outcomes could explain the success of SII. We aimed to determine the effect on islet graft function and insulin independence of SII using these new protocols, without the use of exenatide.. Seventeen islet transplant recipients underwent SIIs after developing graft dysfunction requiring insulin use. For induction therapy, four subjects received daclizumab induction therapy, whereas 13 subjects received thymoglobulin and etanercept. Maintenance immunosuppression consisted of sirolimus+tacrolimus or tacrolimus+cellcept.. SII was performed 49.3+/-4.8 months (mean+/-SEM) after the preceding islet transplant. Subjects received significantly lower islet mass with their SII compared with initial transplant(s) (6076+/-492 vs. 9071+/-796 IEQ/kg; P=0.003). Fifteen of the 17 subjects (88.2%) became insulin independent 2.4+/-0.5 months after SII. Insulin-independent duration after SII exceeded that of the initial transplant(s) (24.8+/-2.2 vs. 14.2+/-2.6 months by Kaplan-Meier analysis, P=0.009). Subjects show improved glycemic control after SII (HbA1c 7.0%+/-0.2% pre-SII vs. 6.1%+/-0.2% post-SII, P=0.005) and did not become immunosensitized.. Using current protocols, SII in the absence of exenatide results in impressive insulin-independence rates and the durability of insulin independence seems to be promising. However, a beneficial effect of exenatide should not be discounted until tested in randomized controlled studies.

Topics: Antilymphocyte Serum; Blood Glucose; C-Peptide; Drug Therapy, Combination; Etanercept; Female; Glycated Hemoglobin; Humans; Hyperglycemia; Hypoglycemic Agents; Immunoglobulin G; Immunosuppressive Agents; Insulin; Islets of Langerhans Transplantation; Male; Postoperative Complications; Receptors, Tumor Necrosis Factor; Sirolimus; Tacrolimus

Reports on the use of sirolimus (SRL) in pancreas transplantation are still limited. The aim of this study was to evaluate the outcome of SRL conversion in pancreas transplant patients. Among 247 patients undergoing simultaneous kidney-pancreas or solitary pancreas transplantation, 33 (13%) were converted to SRL. The reasons for conversion were calcineurin inhibitors (CNI) nephrotoxicity (n = 24; 73%), severe neurotoxicity owing to CNI (n = 1; 3%), severe and/or recurrent acute rejection episodes (n = 7; 21%), gastrointestinal (GI) side effects of mycophenolate mofetil (MMF; n = 5; 15%), and hyperglycemia (n = 4; 12%). Before conversion, all patients were maintained on a CNI, MMF, and low-dose steroids. They were gradually converted to SRL associated with either CNI or MMF withdrawal. Sixty-three percent (n = 15) of patients who were converted owing to CNI nephrotoxicity, showed stable or improved renal function. At 12 months after conversion, serum creatinine levels were significantly decreased in this group (2.2 +/- 0.5 vs 1.6 +/- 0.3 mg/dL; P = .001) and C-peptide values increased (2.9 +/- 1.1.1 vs 3.1 +/- 1.3 nmol/L; P = .018). The only patient with leucoencephalopathy showed improved neurologic status after SRL conversion. All patients converted to SRL because of GI side effects of MMF showed improvements, and none of those converted because of hyperglycemia experienced improvement. There were no episodes of acute rejection after conversion. We concluded that conversion to SRL in pancreas transplantation should be considered an important alternative strategy, particularly for CNI nephrotoxicity and neurotoxicity, and in cases of severe diarrhea due to MMF.

Topics: Adult; Calcineurin Inhibitors; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Female; Humans; Hyperglycemia; Immunosuppressive Agents; Kidney Transplantation; Male; Middle Aged; Mycophenolic Acid; Pancreas Transplantation; Retrospective Studies; Sirolimus; Young Adult