angiotensinogen and Kidney-Failure--Chronic

Autosomal dominant polycystic kidney disease (ADPKD) is the most common inherited disease of the kidneys and is marked by progressive cyst growth and decline in kidney function, resulting in end-stage renal disease (ESRD). Hypertension is thought to be a significant modifying factor in the progression of renal failure in ADPKD. A number of genetic variations involved in renin-angiotensin-aldosterone system (RAAS) pathway genes have clinical or physiological impacts on pathogenesis of hypertension-induced ESRD in ADPKD. Information on RAAS pathway gene polymorphisms and their association with ESRD and ADPKD, published till March 2013, was collected using MEDLINE search. The present review deals with RAAS gene polymorphisms focused on hypertension-induced ESRD in ADPKD in different populations. The results were inconclusive and limited by heterogeneity in the study designs and the population stratification. In lieu of applying next generation sequencing technologies to study complex diseases, it is also possible to apply the same to unravel the complexity of ESRD in ADPKD.

Topics: Angiotensinogen; Cytochrome P-450 CYP11B2; Humans; Hypertension; Kidney Failure, Chronic; Nitric Oxide Synthase Type III; Peptidyl-Dipeptidase A; Polycystic Kidney, Autosomal Dominant; Polymorphism, Genetic; Receptor, Angiotensin, Type 1; Receptor, Angiotensin, Type 2; Renin; Renin-Angiotensin System

Association between angiotensinogen (AGT) M235T gene polymorphism and end-stage renal disease (ESRD) risk is still controversial. This meta-analysis was performed to evaluate the association of AGT M235T gene polymorphism with ESRD susceptibility. A predefined literature search and selection of eligible relevant studies were performed to collect data from electronic databases of PubMed, Embase and Cochrane Library. Sixteen literatures were identified for the analysis of association of AGT M235T gene polymorphism with ESRD risk. T allele and TT genotype were associated with ESRD susceptibility in Caucasians (T: OR = 1.13, 95 % CI: 1.02-1.25, P = 0.02; TT: OR = 1.22, 95 % CI: 1.03-1.45, P = 0.02). However, MM genotype might not play a protective role against ESRD risk in Caucasians. Furthermore, there was no a markedly positive association between AGT M235T gene polymorphism and ESRD susceptibility in overall populations, Asians and Africans. In conclusion, T allele or TT homozygote is associated with the onset of ESRD in Caucasians. However, more studies should be performed in the future.

Topics: Amino Acid Substitution; Angiotensinogen; Case-Control Studies; Genetic Association Studies; Genetic Predisposition to Disease; Humans; Kidney Failure, Chronic; Polymorphism, Genetic; Publication Bias; Risk

African Americans shoulder a disproportionately high burden of kidney disease when compared with white Americans. While environmental factors such as poverty and poor health habits, and the high prevalence of risk factors such as obesity, contribute to the high rate of kidney disease in this population, genetic factors may also contribute. Studies of polymorphisms in genes encoding the proteins of the renin-angiotensin-aldosterone system have identified alleles that are associated with kidney disease or changes in renal function in some populations. A higher prevalence of such alleles in African Americans may contribute to the increased prevalence of kidney disease. Diabetes mellitus and hypertension, the main causes of end-stage renal disease in the United States, are more prevalent in African Americans. However, no direct links between diabetic or hypertensive kidney disease and any genetic polymorphisms seen in African Americans have been identified. Further research is thus required to elucidate the genetic components that contribute to the high prevalence of kidney disease in African Americans.

Topics: Angiotensinogen; Black or African American; Black People; Diabetic Nephropathies; Humans; Hypertension; Kallikreins; Kidney Failure, Chronic; Peptidyl-Dipeptidase A; Polymorphism, Genetic; Prevalence; Renin-Angiotensin System; United States

Studies on genetic variability in the renin-angiotensin system (RAS) provide intriguing data that support its possible relevance to renal pathophysiology. However, from the discrepancies between different studies it is clear that RAS polymorphisms do not provide simple markers for renal prognosis or therapy response. Rather than attempting to force a conclusion from the available discrepancies, we should attempt to develop strategies from the current state of knowledge to attack this complex issue from different angles. Unraveling their functional impact in renal pathophysiology can provide a framework for understanding that can guide further studies with the eventual purpose of improving the prognosis of renal patients. Clinical association studies should be large and prospective, to obtain the necessary robustness, with proper attention paid to the role of contextual factors. Moreover, studies elucidating the physiologic mechanisms of the genetic determinants of the disease phenotype are of prime importance. Such information is vital, not only to make sense of observed associations, but all the more so if one wants to apply the insights on the role of genetic factors into better strategies for disease intervention.

Topics: Angiotensin Receptor Antagonists; Angiotensin-Converting Enzyme Inhibitors; Angiotensinogen; Diabetic Nephropathies; Genetic Variation; Humans; Kidney Failure, Chronic; Peptidyl-Dipeptidase A; Receptors, Angiotensin; Renin-Angiotensin System

Topics: Adrenergic beta-Antagonists; Adult; Aldosterone; Angiotensinogen; Angiotensins; Animals; Blood Pressure; Female; Humans; Hyperaldosteronism; Hypertension; Hypertension, Malignant; Hypertension, Renovascular; Kidney Failure, Chronic; Male; Molecular Weight; Peptidyl-Dipeptidase A; Radioimmunoassay; Renin

In patients with diabetes, albuminuria is a risk marker of end-stage renal disease and cardiovascular events. An increased renin-angiotensin system activity has been reported to play an important role in the pathological processes in these conditions. We compared the effect of aliskiren, a direct renin inhibitor (DRI), with that of angiotensin receptor blockers (ARBs) on albuminuria and urinary excretion of angiotensinogen, a marker of intrarenal renin-angiotensin system activity.. We randomly assigned 237 type 2 diabetic patients with high-normal albuminuria (10 to <30 mg/g of albumin-to-creatinine ratio) or microalbuminuria (30 to <300 mg/g) to the DRI group or ARB group (any ARB) with a target blood pressure of <130/80 mmHg. The primary endpoint was a reduction in albuminuria.. Twelve patients dropped out during the observation period, and a total of 225 patients were analyzed. During the study period, the systolic and diastolic blood pressures were not different between the groups. The changes in the urinary albumin-to-creatinine ratio from baseline to the end of the treatment period in the DRI and ARB groups were similar (-5.5% and -6.7%, respectively). In contrast, a significant reduction in the urinary excretion of angiotensinogen was observed in the ARB group but not in the DRI group. In the subgroup analysis, a significant reduction in the albuminuria was observed in the ARB group but not in the DRI group among high-normal albuminuria patients.. DRI and ARB reduced albuminuria in hypertensive patients with type 2 diabetes. In addition, ARB, but not DRI, reduced albuminuria even in patients with normal albuminuria. DRI is not superior to ARB in the reduction of urinary excretion of albumin and angiotensinogen.

Topics: Albuminuria; Amides; Angiotensin Receptor Antagonists; Angiotensinogen; Antihypertensive Agents; Blood Pressure; Creatinine; Diabetes Mellitus, Type 2; Diabetic Nephropathies; Fumarates; Humans; Hypertension; Kidney Failure, Chronic; Prospective Studies; Renin; Renin-Angiotensin System; Treatment Outcome

Activation of the rennin-angiotensin system (RAS) is thought to contribute to hypertension and proteinuria, and eventually to the progression of chronic kidney disease (CKD). Recent evidence suggests that urinary angiotensinogen (UAGT) excretion reflects activation of the intrarenal RAS. This study was performed to determine the effect of losartan on proteinuria and UAGT excretion in non-diabetic patients with CKD with non-nephrotic-range proteinuria.. Thirty-two patients with non-nephrotic-range proteinuria (0.045-0.23 g/mmol creatinine) and normal renal function between April 2005 and April 2006 were randomised to a losartan (n=17) or a control (n=15) group. Patients in the losartan group received losartan 50 mg/day, and the doses were titrated up to 100 mg/day after 6 weeks. Serum and urinary angiotensinogen concentrations were measured by sandwich ELISA. The primary end point was the percentage change in proteinuria. The secondary end points were changes in estimated glomerular filtration rate and UAGT excretion. The follow-up period was 24 months.. Baseline characteristics in the two groups were similar. After 24 months, losartan had reduced urinary protein excretion by 43% (from mean±SD 0.13±0.04 to 0.073±0.03 g/mmol, p<0.0001), but proteinuria had not changed in the control group. The percentage change in mean arterial pressure did not differ between the groups. Losartan decreased logarithmically converted UAGT excretion (from 1.58±0.47 to 1.00±0.52, p=0.001). Estimated glomerular filtration rate decreased significantly only in the control group.. Losartan significantly decreased proteinuria and UAGT excretion, and preserved renal function in non-diabetic patients with CKD.

Topics: Adult; Angiotensin II Type 1 Receptor Blockers; Angiotensinogen; Enzyme-Linked Immunosorbent Assay; Female; Follow-Up Studies; Humans; Kidney Failure, Chronic; Losartan; Male; Middle Aged; Proteinuria; Renin-Angiotensin System

Genes of the renin-angiotensin system (RAS) are involved in the progression of renal failure. Among them, the angiotensin-converting enzyme (ACE), angiotensinogen (AGT) and angiotensin II type 1 receptor (AT1R) genes are of particular interest. We examined polymorphisms of these three genes for association with the development of interstitial nephritis and progression to end-stage renal failure. The allele frequency and genotype distribution were compared in 90 patients with interstitial nephritis and 200 healthy controls. DNA samples were genotyped by polymerase chain reaction (PCR). We did not find statistically significant differences between groups in the insertion/deletion polymorphism of the ACE gene. An involvement of M235T polymorphism of the AGT gene in renal disease was observed in our study. The frequency of the T allele was higher in patients than in controls (32% vs. 24%). In the A1166C AT1R polymorphism the homozygous CC genotype was also more frequent in interstitial nephritis patients (7% vs. 3.5%). In patients carrying the C allele, an average time to ESRD was significantly shorter than in subjects with the AA genotype. Our study shows the association of the AGT and AT1R gene polymorphisms with the development and progression of interstitial nephritis. The C allele of the A1166C polymorphism appears to be a risk factor for faster disease progression.

Topics: Adult; Angiotensin I; Angiotensinogen; Disease Progression; Female; Gene Expression Regulation; Genetic Predisposition to Disease; Genetic Variation; Humans; Kidney Failure, Chronic; Male; Middle Aged; Nephritis, Interstitial; Polymorphism, Genetic; Receptor, Angiotensin, Type 1; Renin-Angiotensin System; Risk Assessment; Statistics as Topic

Type 2 diabetes mellitus (T2DM) and hypertension are common chronic diseases mainly associated with the development and progression of end-stage renal disease (ESRD) leading to morbidity and mortality. Gene polymorphisms linked to the renin-angiotensin (

Topics: Aged; Angiotensinogen; Diabetes Mellitus, Type 2; Egypt; Female; Gene Frequency; Genetic Predisposition to Disease; Humans; Hypertension; Kidney Failure, Chronic; Male; Middle Aged; Mutation, Missense; Polymorphism, Single Nucleotide

Novel potential tubular biomarkers in diabetic nephropathy could improve risk stratification and prediction. The study aimed to evaluate the association of tubular damage markers with rapid renal progression and incidence of end stage renal disease (ESRD) in type 2 diabetes (T2DM).. A prospective cohort study, involving a total of 257 patients with T2DM, was included. The baseline values of urine albumin, cystatin-C, angiotensinogen, kidney injury molecule-1 (KIM-1) and neutrophil-gelatinase associated lipocalin (NGAL) were measured. The composite outcomes included a rapid glomerular filtration rate (GFR) decline or incident of ESRD at 3-year follow-up.. The composite outcomes were noted in 26.1%. Using univariate followed by multivariate COX proportional hazard regression analysis, the patients with highest quartiles of urine cystatin-C (HR 2.96, 95% CI, 1.38-6.35), urine angiotensinogen (HR 2.93, 95% CI, 1.40- 6.13) urine KIM-1 (HR 2.77, 95% CI, 1.27-6.05) and urine NGAL (HR 2.53, 95% CI, 1.11-5.76) were significantly associated with rapid renal progression when compared with the patients with the lowest quartiles of all tubular biomarkers.. Patients with T2DM with high levels of baseline urine tubular biomarkers (cystatin-C, angiotensinogen, KIM-1 and NGAL) had a greater incidence of ESRD and rapid GFR decline.

Topics: Aged; Albuminuria; Angiotensinogen; Biomarkers; Cohort Studies; Cystatin C; Diabetes Mellitus, Type 2; Diabetic Nephropathies; Disease Progression; Female; Glomerular Filtration Rate; Hepatitis A Virus Cellular Receptor 1; Humans; Kidney Failure, Chronic; Kidney Tubules; Lipocalin-2; Male; Middle Aged; Prospective Studies; Sensitivity and Specificity

Hemolytic uremic syndrome (HUS) is a type of thrombotic microangiopathy, in the course of which some patients may develop chronic kidney disease (CKD). It is clinically important to investigate the markers of a poor prognosis. The levels of angiotensinogen (AGT) and interleukin-18 (IL-18) in serum and urine were evaluated. Study was conducted in 29 children with a history of HUS. Serum and urine AGT concentration was significantly higher in children after HUS as compared to the control group. No differences depending on the type of HUS and gender were noted. The serum concentration of IL-18 in children after HUS was significantly lower, whereas in urine did not differ significantly between the sick and healthy children. A negative correlation between the concentration of AGT in serum and albuminuria in patients after HUS was detected. The results indicate that the concentration of AGT in serum and urine in children after HUS increases, which may indicate the activation of the intrarenal renin-angiotensin-aldosterone system. The statement, that AGT may be a good biomarker of CKD after acute kidney injury due to HUS requires prospective studies with follow-up from the acute phase of the disease on a larger group of patients. Reduced IL-18 serum concentration in children after HUS with no difference in its urine concentration may indicate a loss of the protective effects of this cytokine on renal function due to previously occurred HUS.

Topics: Adolescent; Angiotensinogen; Biomarkers; Child; Child, Preschool; Female; Hemolytic-Uremic Syndrome; Humans; Infant; Interleukin-18; Kidney Failure, Chronic; Male; Reproducibility of Results; Sensitivity and Specificity

Topics: Angiotensin II; Angiotensinogen; Humans; Kidney; Kidney Failure, Chronic; Renin; Renin-Angiotensin System

Hemodialysis (HD) is the most commonly-used renal replacement therapy for patients with end-stage renal disease worldwide. Arterio-venous fistula (AVF) is the vascular access of choice for HD patients with lowest risk of infection and thrombosis. In addition to environmental factors, genetic factors may also contribute to malfunction of AVF. Previous studies have demonstrated the effect of genotype polymorphisms of angiotensin converting enzyme on vascular access malfunction. We conducted a multicenter, cross-sectional study to evaluate the association between genetic polymorphisms of renin-angiotensin-aldosterone system and AVF malfunction. Totally, 577 patients were enrolled. Their mean age was 60 years old and 53% were male. HD patients with AVF malfunction had longer duration of HD (92.5 ± 68.1 vs. 61.2 ± 51.9 months, p < 0.001), lower prevalence of hypertension (44.8% vs. 55.3%, p = 0.025), right-sided (31.8% vs. 18.4%, p = 0.002) and upper arm AVF (26.6% vs. 9.7%, p < 0.001), and higher mean dynamic venous pressure (DVP) (147.8 ± 28.3 vs. 139.8 ± 30.0, p = 0.021). In subgroup analysis of different genders, location of AVF and DVP remained significant clinical risk factors of AVF malfunction in univariate and multivariate binary logistic regression in female HD patients. Among male HD patients, univariate binary logistic regression analysis revealed that right-side AVF and upper arm location are two important clinical risk factors. In addition, two single nucleotide polymorphisms (SNPs), rs275653 (Odds ratio 1.90, p = 0.038) and rs1492099 (Odds ratio 2.29, p = 0.017) of angiotensin II receptor 1 (AGTR1), were associated with increased risk of AVF malfunction. After adjustment for age and other clinical factors, minor allele-containing genotype polymorphisms (AA and CA) of rs1492099 still remained to be a significant risk factor of AVF malfunction (Odds ratio 3.63, p = 0.005). In conclusion, we demonstrated that rs1492099, a SNP of AGTR1 gene, could be a potential genetic risk factor of AVF malfunction in male HD patients.

Topics: Aged; Angiotensinogen; Arteriovenous Fistula; Case-Control Studies; Cross-Sectional Studies; Female; Genetic Predisposition to Disease; Humans; Kidney Failure, Chronic; Male; Middle Aged; Peptidyl-Dipeptidase A; Polymorphism, Single Nucleotide; Receptor, Angiotensin, Type 1; Receptor, Angiotensin, Type 2; Renal Dialysis; Sex Factors

The renin-angiotensin system (RAS) is thought to regulate blood pressure and to be an independent risk factor for the development of left ventricular hypertrophy (LVH) and carotid intima-media thickness (CIMT). Locally produced RAS in most tissues has been recently described. It has been reported that urinary angiotensinogen levels provide a specific index of the intrarenal RAS status and is significantly correlated with blood pressure and proteinuria. The aim of this study was to evaluate the relationship of local intrarenal RAS with LVH and CIMT in hypertensive renal transplant recipients (RTRs).. A total of 96 non-diabetic RTRs (50 hypertensive patients, 46 normotensive patients) were included in this study. Urinary angiotensinogen (UAGT)/urinary creatinine (Ucre) was significantly higher in hypertensive patients compared with normotensive patients (p < 0.01). Left ventricular mass (LVM)I and CIMT were significantly higher in hypertensive patients compared with the normotensive patients (p < 0.01). Importantly, a significant positive correlation was found between UAGT/Ucre levels and LVMI (r = 0.724, p = 0.012) and also CIMT (r = 0.452, p = 0.02) in hypertensive RTRs.. These data indicate that UAGT is increased in hypertensive RTRs, and local RAS may play an important role in the development of cardiovascular abnormalities in hypertensive renal transplant recipients.

Topics: Angiotensinogen; Blood Pressure Monitoring, Ambulatory; Carotid Intima-Media Thickness; Case-Control Studies; Creatinine; Female; Follow-Up Studies; Glomerular Filtration Rate; Graft Survival; Humans; Hypertension; Hypertrophy, Left Ventricular; Kidney Failure, Chronic; Kidney Function Tests; Kidney Transplantation; Male; Middle Aged; Postoperative Complications; Prognosis; Proteinuria; Renin-Angiotensin System; Risk Factors; Transplant Recipients

This study aimed at investigating if M235T polymorphism in the AGT gene and A/G(I8-83) polymorphism in the REN gene correlate with end-stage renal disease (ESRD).. We analyzed 173 ESRD patients and 329 individuals with normal kidney function for differences in the genotype distribution of AGT-M235T and REN-A/G(I8-83) polymorphisms between the two groups. The data for cases and controls were compared using the χ(2) test.. We found significantly higher levels of serum creatinine and CRP in cases in comparison to controls (p < 0.0001). Data comparison showed a significant association of AGT M235T substitution with ESRD in the dominant model (p = 0.008) and in the comparison of the heterozygous substitution with the homozygous common genotype (p = 0.005). Similarly, REN A/G(I8-83) polymorphism showed a significant difference in the distribution of genotypes between cases and controls (p < 0.038) such that a heterozygous substitution was significantly more common in the ESRD cases in comparison to the homozygous common genotype (p = 0.023).. We conclude that heterozygous substitutions at the AGT M235T and REN A/G(I8-83) loci correlate significantly with ESRD in a north Indian population.

Topics: Amino Acid Substitution; Angiotensinogen; DNA; Gene Frequency; Genes, ras; Genotype; Humans; India; Kidney Failure, Chronic; Polymorphism, Genetic; Renin

Recent studies have indicated that angiotensinogen (AGT) is also locally produced in the kidney and that urinary AGT is a marker of local renal renin-angiotensin system activation. Because urinary AGT levels are significantly higher in patients with chronic kidney disease (CKD) than in patients without CKD and correlate with urinary albumin and other levels, urinary AGT is increasingly recognized as a marker for CKD monitoring, prognosis, and treatment. In this study, we investigated urinary AGT levels in renal transplant recipients.. Among the patients who were treated as outpatients at the Department of Urology of Osaka City University Hospital from March 2012 to April 2013, 146 stable renal transplant recipients and 50 donors who gave informed consent were studied. Urinary AGT and creatinine (Cr) levels were measured. The urinary AGT-to-Cr ratio was calculated, and its correlation with clinical parameters was examined.. The urinary AGT-to-Cr ratio of the renal transplant recipients was significantly higher than that of the renal transplant donors (P = .0143). Furthermore, the urinary AGT-to-Cr ratio had a significantly positive correlation with the urinary albumin-to-Cr ratio (ACR; r = 0.39, P < .0001), while on the other hand, it had a significantly negative correlation with estimated glomerular filtration rate (eGFR; r = -0.31, P = .0002). Multiple linear regression analysis of factors associated with eGFR showed that urinary AGT was a significant and independent factor after adjusting for age, sex, and ACR.. Our results indicated that urinary AGT levels were elevated in renal transplant recipients. In addition, urinary AGT significantly correlated with renal function and degree of albuminuria.

Topics: Adult; Aged; Angiotensinogen; Biomarkers; Case-Control Studies; Female; Humans; Kidney Failure, Chronic; Kidney Transplantation; Male; Middle Aged

Familial clustering and presumed genetic risk for type 2 diabetic (T2D) and non-diabetic end-stage kidney disease (ESKD) appear strong in African Americans. Examination of exome sequencing data in African American T2D-ESKD cases and non-diabetic non-nephropathy controls identified two low-frequency variants in the RREB1 gene, a repressor of the angiotensinogen (AGT) gene previously associated with kidney function, as being associated with T2D-ESKD: rs9379084 (P = 0.00087, OR = 0.26; D1171N) and rs41302867 (P = 0.00078, OR = 0.21; splice site variant). Rs41302867 replicated association in an independent sample of African Americans with T2D-ESKD [rs41302867 P = 0.033 (OR = 0.50)], and a trend towards rs9379084 association was observed (P = 0.070). In European Americans with T2D-ESKD compared with European American population based controls, both RREB1 variants replicated association [rs9379084 P = 1.67 × 10(-4) (OR = 0.54) and rs41302867 P = 0.013 (OR = 0.69)]. Rs9379084 was not associated with non-T2D-ESKD or T2D in African Americans (P = 0.55 and P = 0.37, respectively), but was associated with T2D in European Americans (P = 0.014, OR = 0.65). In African Americans, rs41302867 was associated with non-T2D-ESKD [P = 0.036 (OR = 0.54)] and hypertension attributed ESKD [H-ESKD, P = 0.029 (OR = 0.50)]. A meta-analysis combining African American and European American T2D-ESKD data revealed P = 3.52 × 10(-7) and 3.70 × 10(-5) for rs9379084 and rs41302867 association, respectfully. A locus-wide analysis evaluating putatively functional SNPs revealed several nominal associations with T2D-ESKD, non-T2D-ESKD and T2D in African and European Americans. RREB1 is a large, complex gene which codes a multidomain zinc finger binding protein and transcription factor. We posit that variants in RREB1 modulate seemingly disparate phenotypes (i.e. T2D, T2D-ESKD and non-T2D-ESKD) through altered activity resulting from splice site and missense variants.

Topics: Aged; Alternative Splicing; Angiotensinogen; Black or African American; Case-Control Studies; Diabetes Mellitus, Type 2; DNA-Binding Proteins; Female; Genetic Loci; Genetic Predisposition to Disease; Genome-Wide Association Study; Haplotypes; Humans; Kidney Failure, Chronic; Male; Middle Aged; Mutation, Missense; Odds Ratio; Polymorphism, Single Nucleotide; Transcription Factors; White People

End-stage kidney disease patients continue to have markedly increased cardiovascular disease morbidity and mortality. Analysis of genetic factors connected with the renin-angiotensin system that influences the survival of the patients with end-stage kidney disease supports the ongoing search for improved outcomes.. To assess survival and its association with the polymorphism of renin-angiotensin system genes: angiotensin I-converting enzyme insertion/deletion and angiotensinogen M235T in patients undergoing hemodialysis.. Our study was designed to examine the role of renin-angiotensin system genes. It was an observational study. We analyzed 473 chronic hemodialysis patients in four dialysis units in the state of Rio de Janeiro. Survival rates were calculated by the Kaplan-Meier method and the differences between the curves were evaluated by Tarone-Ware, Peto-Prentice, and log rank tests. We also used logistic regression analysis and the multinomial model. A p value ≤ 0.05 was considered to be statistically significant. The local medical ethics committee gave their approval to this study.. The mean age of patients was 45.8 years old. The overall survival rate was 48% at 11 years. The major causes of death were cardiovascular diseases (34%) and infections (15%). Logistic regression analysis found statistical significance for the following variables: age (p = 0.000038), TT angiotensinogen (p = 0.08261), and family income greater than five times the minimum wage (p = 0.03089), the latter being a protective factor.. The survival of hemodialysis patients is likely to be influenced by the TT of the angiotensinogen M235T gene.

Topics: Adult; Angiotensinogen; Cardiovascular Diseases; Diabetes Complications; Female; Humans; Kaplan-Meier Estimate; Kidney Failure, Chronic; Logistic Models; Male; Middle Aged; Peptidyl-Dipeptidase A; Polymorphism, Genetic; Renal Dialysis; Renin-Angiotensin System; Risk Factors; Time Factors

Chronic kidney disease (CKD) is highly prevalent in Taiwan and an increasing number of patients are affected, with a high risk of progression to end-stage renal disease and huge medical expenses. It has been predicted that the presence of hypertension increases with decreasing renal function due to a decrease in sodium excretion and activation of the renin-angiotensin system (RAS). The aim of this study was to investigate the influence of genetic variants of the RAS gene on CKD. We performed a case control association study and genotyped 135 CKD patients and 270 healthy controls among Han Chinese in Taiwan. All subjects were genotyped for angiotensinogen (AGT-M235T, T174M, A-20C), angiotensin-I converting enzyme (ACE-A2350G) and angiotensin II type 1 receptor (AGTR1-A1166C, C573T, C-521T) polymorphisms of RAS genes by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis. Significant associations were observed in ACE-A2350G and AGTR1-C573T polymorphism between CKD patients and controls. In regard to ACE-A2350G, compared with the AA genotype the GG genotype protected against CKD (adjusted odds ratio [OR] = 0.34; p = 0.01). In regard to AGTR1-C573T, the CT genotype was a risk for CKD compared with the CC genotype (adjusted OR = 1.82; p = 0.03). We conclude that ACE-A2350G and AGTR1-C573T polymorphisms are likely candidate determinants of CKD.

Topics: Angiotensinogen; Asian People; Case-Control Studies; China; Gene Frequency; Genetic Predisposition to Disease; Haplotypes; Humans; Kidney Failure, Chronic; Peptidyl-Dipeptidase A; Polymorphism, Single Nucleotide; Receptor, Angiotensin, Type 1; Renin-Angiotensin System

Uremic toxins are considered to have a determinant pathological role in the progression of chronic kidney disease. The aim of this study was to define the putative pathological roles of the renal renin-angiotensin-aldosterone system (RAAS) and renal tubular epithelial-to-mesenchymal transition (EMT) in kidney fibrosis induced by (indoxyl sulfate) IS and (p-cresol sulfate) PCS.. Mouse proximal renal tubular cells (PKSV-PRs) treated with IS or PCS were used. Half-nephrectomized B-6 mice were treated with IS or PCS for 4 weeks. In the losartan treatment study, the study animal was administrated with IS+losartan or PCS+losartan for 4 weeks.. IS and PCS significantly activated the intrarenal RAAS by increasing renin, angiotensinogen, and angiotensin 1 (AT1) receptor expression, and decreasing AT2 receptor expression in vitro and in vivo. IS and PCS significantly increased transforming growth factor-β1 (TGF-β1) expression and activated the TGF-β pathway by increasing Smad2/Smad2-P, Smad3/Smad3-P, and Smad4 expression. The expression of the EMT-associated transcription factor Snail was increased by IS and PCS treatment. IS and PCS induced the phenotype of EMT-like transition in renal tubules by increasing the expression of fibronectin and α-smooth muscle actin and decreasing the expression of E-cadherin. Losartan significantly attenuated the expression of TGF-β1 and Snail, and decreased kidney fibrosis induced by IS and PCS in vivo.. Activating the renal RAAS/TGF-β pathway has an important pathological role in chronic kidney injury caused by IS and PCS. IS and PCS may increase Snail expression and induce EMT-like transition.

Topics: Angiotensinogen; Animals; Cresols; Epithelial-Mesenchymal Transition; Fibrosis; Gene Expression Regulation; Indican; Kidney; Kidney Failure, Chronic; Kidney Tubules; Losartan; Male; Mice; Models, Biological; Receptor, Angiotensin, Type 1; Renin; Renin-Angiotensin System; Snail Family Transcription Factors; Sulfuric Acid Esters; Transcription Factors; Transforming Growth Factor beta1; Uremia

Biomarkers for early detection of chronic kidney disease are needed, as millions of patients suffer from chronic diseases predisposing them to kidney failure. Protein microarrays may also hold utility in the discovery of auto-antibodies in other conditions not commonly considered auto-immune diseases. We hypothesized that proteins are released as a consequence of damage at a cellular level during end-organ damage from renal injury, not otherwise recognized as self-antigens, and an adaptive humoral immune response to these proteins might be detected in the blood, as a noninvasive tracker of this injury. The resultant antibodies (Ab) detected in the blood would serve as effective biomarkers for occult renal injury, enabling earlier clinical detection of chronic kidney disease than currently possible, because of the redundancy of the serum creatinine as a biomarker for early kidney injury. To screen for novel autoantibodies in chronic kidney disease, 24 protein microarrays were used to compare serum Ab from patients with chronic kidney disease against matched controls. From a panel of 38 antigens with increased Ab binding, four were validated in 71 individuals, with (n=50) and without (n=21) renal insufficiency. Significant elevations in the titer of novel auto-Ab were noted against angiotensinogen and PRKRIP1 in renal insufficiency. Current validation is underway to evaluate if these auto-Ab can provide means to follow the evolution of chronic kidney disease in patients with early stages of renal insufficiency, and if these rising titers of these auto-Ab correlate with the rate of progression of chronic kidney disease.

Topics: Amino Acid Motifs; Amino Acid Sequence; Angiotensinogen; Animals; Autoantibodies; Cell Differentiation; Embryonic Stem Cells; Humans; Kidney Failure, Chronic; Mice; Molecular Sequence Data; Phosphopeptides; Phosphoproteins; Phosphorylation; Protein Array Analysis; Proteome; RNA-Binding Proteins

Genetic polymorphisms of the renin-angiotensin system (RAS) have been reported to play an important role in the pathogenesis of diabetes mellitus and hypertension. In addition, a close association has been reported between RAS and the progression of both diabetes and hypertension. But the role of RAS on the development of posttransplantation diabetes mellitus (PTDM) is not known. For this purpose we investigated the association of polymorphisms in the genes for angiotensin-converting enzyme (ACE) and angiotensinogen (AGT) with the development of PTDM.. Genotyping for ACE insertion/deletion (I/D) and AGT M235T polymorphisms was performed in 50 patients who underwent renal transplantation during a 5-year period. Group 1 consisted of 23 recipients who developed PTDM and group 2 consisted of 27 recipients that did not have PTDM.. Of 50 patients, 13 (26%) showed the ACE DD, 21 (42%) the ACE ID, and 16 the ACE II genotype. The frequencies of AGT MM, AGT MT, and AGT TT were 0, 54%, and 46%, respectively. Compared with group 2, there were high frequencies of the AGT TT genotype in group 1 recipients (P<.001). In addition the ACE DD genotype was found significantly higher in group 1 patients compared with group 2 patients (P=.001).. The high frequencies of the AGT TT genotype and ACE DD genotype in recipients may contribute to the high prevalence of PTDM. Our data suggest a synergistic effect between the ACE and AGT polymorphism in the risk of PTDM, but to support this theory a larger patient group must be studied.

Topics: Adult; Angiotensinogen; Diabetes Complications; Diabetes Mellitus; Disease Progression; Female; Gene Deletion; Genotype; Humans; Hypertension; Immunosuppressive Agents; Kidney Failure, Chronic; Kidney Transplantation; Male; Middle Aged; Peptidyl-Dipeptidase A; Polymorphism, Genetic; Transplantation, Homologous

Genetic variability in the renin-angiotensin-aldosterone system may modify renal responses to injury and disease progression. The angiotensin I-converting enzyme (ACE) gene insertion/deletion (I/D), the angiotensinogen (AGT) gene, M235T, the aldosterone synthase (CYP11B2) gene, C-344T, and the angiotensin II type 1 receptor (AT1R) gene, A1166C, have been shown to be associated with IgA nephropathy (IgAN) and its progression. We determined the presence of these polymorphisms in 130 Chinese patients with IgAN, including 47 patients with end-stage renal disease (ESRD) and 120 healthy Chinese subjects, to assess their impact on the susceptibility to disease and the liability of progression to ESRD.. Genotyping was performed with DNA isolated from peripheral leucocytes using polymerase chain reaction amplification of the polymorphic sequence, restriction enzyme digestion, and separation and identification of DNA fragments. Clinical data from renal biopsies were collected.. ACE, AGT, CYP and AT1R genotype distributions were similar in patients with IgAN and in controls. Comparing patients with ESRD (IgAN-ESRD) and those without ESRD (IgAN-non ESRD), there was a significant increase only in the ACE DD genotype (P < 0.05) among the four gene polymorphisms. There was significant dominance of the male (P < 0.05), more marked hypertension (P < 0.01), proteinuria (P < 0.01) and increased serum creatinine during renal biopsy (P < 0.01) in the IgAN-ESRD group.. Among the ACE, AGT, AT1R and CYP gene polymorphisms, only the DD genotype may predispose the individual to increased risk of progression to ESRD in the Chinese population.

Topics: Adult; Angiotensinogen; Asian People; Cytochrome P-450 CYP11B2; Female; Genetic Predisposition to Disease; Genotype; Glomerulonephritis, IGA; Humans; Kidney Failure, Chronic; Male; Middle Aged; Peptidyl-Dipeptidase A; Polymorphism, Genetic; Receptor, Angiotensin, Type 1; Renin-Angiotensin System

Aim. Renin-angiotensin system (RAS) gene mutations have been implicated as a risk factor for the presence and progression of renal disease in vesicoureteral reflux (VUR). However, the results are contradictory, and the effects of RAS polymorphisms in VUR patients with end-stage renal disease (ESRD) have not been defined yet. This study was designed to evaluate the angiotensin-converting enzyme insertion/deletion (ACE-I/D), angiotensinogen (AGT) M235T, and angiotensin II receptor type 1 (ATR1) A1166C and type 2 (ATR2) C3123A gene polymorphisms as risk factors for progression to ESRD in patients with VUR. Methods. ACE-I/D, AGT-M235T, ATR1-A1166C, and ATR2-C3123A were identified in 161 ESRD patients (52 female, 109 male; 77 renal transplant, 84 dialysis; age: 34.4 +/- 11.2 years). VUR was the ESRD etiology in 40 patients. Genetic polymorphisms of the ACE gene I/D, AGT gene M235T, ATR1 gene A1166C, and ATR2 gene C3123A were identified in all of the patients. Results. We detected no linkage between genetic polymorphisms of ATR1-, ATR2-, AGT-, and VUR-related ESRD. When ACE gene was considered, VUR(+) patients had 63.6% DD, 36.4% ID, and no II alleles, whereas VUR(-) patients had 48.6% DD, 43.2% ID, and 8.1% II alleles. Conclusion. A striking feature of VUR-related ESRD patients was the absence of II alleles, so the DD genotype may be accepted as a genetic susceptibility factor for progression to ESRD in VUR patients.

Topics: Adult; Angiotensinogen; Ataxia Telangiectasia Mutated Proteins; Cell Cycle Proteins; Disease Progression; Female; Gene Deletion; Gene Frequency; Genetic Predisposition to Disease; Humans; Kidney Failure, Chronic; Male; Middle Aged; Mutagenesis, Insertional; Peptidyl-Dipeptidase A; Polymorphism, Genetic; Protein Serine-Threonine Kinases; Renin-Angiotensin System; Risk Assessment; Risk Factors; Vesico-Ureteral Reflux

End-stage renal disease (ESRD) is a complex phenotype resulting from underlying kidney diseases of different etiologies as well as from environmental and genetic factors. The responsible genes influencing the development and rate of progression to ESRD have yet to be defined. We examined an association of the three renin-angiotensin system (RAS) gene polymorphisms with renal disease and progression to ESRD in dialyzed patients.. Genotyping was performed in 745 ESRD patients and 520 control subjects for the angiotensin-converting enzyme (ACE) I/D, angiotensinogen (AGT) M235T and angiotensin II type 1 receptor (AT1R) A1166C gene polymorphisms using polymerase chain reaction and gel analysis.. Allele and genotype frequencies of the ACE polymorphism did not differ significantly between ESRD patients and controls. The patient group showed an increased frequency of the T allele of the AGT polymorphism (P = 0.02) and the C allele and CC genotype of the AT1R polymorphism (P<0.01). There was an association of the AT1R gene polymorphism with the progression of renal disease to end-stage failure. The time from diagnosis to the onset of ESRD was significantly shorter in patients carrying the C allele than in subjects with the homozygous AA genotype (4.7 years vs 12.6 years, P<0.001). The observed effect was not associated with hypertension in studied subjects.. The results of our study demonstrate the association between the AT1R A/C polymorphism and renal disease progression. The CC/AC genotype of this polymorphism might serve as a predictor for early ESRD and might be useful in planning therapeutic strategies for individual patients.

Topics: Angiotensinogen; Case-Control Studies; Disease Progression; Female; Genetic Predisposition to Disease; Genotype; Humans; Kidney Failure, Chronic; Male; Middle Aged; Peptidyl-Dipeptidase A; Polymorphism, Genetic; Receptor, Angiotensin, Type 1; Renin-Angiotensin System

Chronic renal failure (CRF) is a major cause of morbidity and mortality after orthotopic liver transplantation (OLTX) and is predominantly caused by calcineurin inhibitors (CI)-induced nephrotoxicity. The activation of the renin angiotensin system (RAS) has been implicated in the pathogenesis of chronic nephrotoxicity from CI.. We retrospectively investigated the genes coding for components of the RAS (ACE gene, Angiotensin II receptor 1 gene, Angiotensinogen gene) in 233 liver transplant recipients receiving Cyclosporine (CsA) or Tacrolimus (Tac) as maintenance immunosuppressant. All patients with serum creatinine (sCr) <1.0 mg/dL (n=143) before orthotopic liver transplantation (OLTX) were included in the final analysis. Patients were than categorized into two groups based upon their most recent postliver transplant sCr level: Group 1 (n=83) with sCr <1.5 mg/dL (mean 1.1+/-0.2) and group 2 (n=60) with sCr > or =1.5 mg/dL (mean 2.5+/-1.3). ACE D/D genotype was found in 57% of patients with sCr > or =1.5 mg/dL compared to 20% of patients with sCr <1.5 mg/dL (P<0.0001). Our analysis strongly suggests that liver transplant patients with ACE gene D/D genotype are at a significant higher risk of developing CI-induced chronic nephrotoxicity.

Topics: Angiotensinogen; Calcineurin Inhibitors; Cyclosporine; Female; Genotype; Graft Rejection; Humans; Immunosuppressive Agents; Kidney Failure, Chronic; Liver Transplantation; Male; Middle Aged; Peptidyl-Dipeptidase A; Receptor, Angiotensin, Type 1; Receptor, Angiotensin, Type 2; Risk Factors; Tacrolimus

Chronic allograft dysfunction (CAD) is the most common cause of allograft failure in the long-term, and current immunologic strategies have little effect on this condition. The renin-angiotensin system (RAS) plays important roles progression of chronic renal disease. It is thought that plasminogen activator inhibitor-1 (PAI-1) functions in the RAS, in addition to involvement in thrombotic risk and fibrosis. This study investigated possible links between angiotensinogen (AGT) genotypes (M235T/MM, MT, TT) and PAI-1 genotypes (4G4G, 4G5G, 5G5G) and CAD assessments of both types of polymorphism were performed in 82 renal allograft recipients. One hundred healthy subjects were also investigated for AGT polymorphism, and 80 healthy subjects for PAI-1 polymorphism. Genotypes were determined using polymerase chain reaction (PCR) sequence-specific primers, and PCR followed by restriction fragment length polymorphism analysis. Kidney recipients with CAD had significantly lower frequencies of the MM genotype and the M allele than the recipients without CAD (p < 0.05 and <0.001). The transplant recipients with CAD also had significantly lower frequencies of the 5G5G genotype and the 5G allele than those without CAD (p < 0.001 and <0.05). Determination of AGT M235T and PAI-1 genotypes prior to transplantation may help identify patients who at risk for chronic renal transplant dysfunction.

Topics: Adult; Angiotensinogen; Female; Genetic Predisposition to Disease; Humans; Kidney Failure, Chronic; Kidney Transplantation; Male; Middle Aged; Plasminogen Activator Inhibitor 1; Polymorphism, Genetic; Renin-Angiotensin System

Genetic polymorphisms of the renin-angiotensin system (RAS) has been associated with cardiovascular events and the progression of nephropathy in several diseases. The objective of this study was to evaluate a possible association of the genetic polymorphisms of RAS with the development and/or progression of lupus nephritis in a Brazilian population. Seventy-five SLE patients with lupus nephropathy (LN group) were compared to 72 SLE patients without LN (SLE group) and 65 healthy individuals (CONTROL group), of sex and ethnic matched, in a Brazilian population sample. Mean global follow-up was 9 +/- 6 years for lupus without nephropathy and 11 +/- 7 years for lupus nephropathy. Following the extraction of genomic DNA from the leukocytes in the peripheral blood, angiotensin converting enzyme (ACE I/D), angiotensinogen (AGT M(235)T) and angiotensin II type 1 receptor (AGTR1 A(1166)C) genotypes were determined by the polymerase chain reaction. No significant difference of ACE, AGT and AGTR1 genotypes distribution between groups was observed in this study. There was no significant association between the variables of the RAS genotypes and the presence of hypertension in SLE. However, an increased frequency ofDD genotype (ACE I/D) was observed in SLE patients with LN who progressed to CRF compared to healthy controls (DD 60%, DI 26.7%, II 13.3% versus 27.7%, 60% and 12.3%, respectively; chi2 = 6.299, P = 0.0429). In the population studied, there was no influence of the RAS genetic polymorphisms in the development of lupus nephropathy, but the progression to CRF was associated with ACE DD polymorphism.

Topics: Adult; Angiotensinogen; Brazil; Case-Control Studies; Disease Progression; Female; Gene Frequency; Genetic Predisposition to Disease; Genotype; Humans; Hypertension; Kidney Failure, Chronic; Lupus Erythematosus, Systemic; Lupus Nephritis; Male; Middle Aged; Peptidyl-Dipeptidase A; Polymorphism, Genetic; Receptor, Angiotensin, Type 1; Renin-Angiotensin System

Obstructive uropathies, including posterior urethral valves (PUVs) and kidney hypodysplasia, are the most frequent cause of renal failure in children. The role of renin-angiotensin system genes in renal and urinary tract development has been observed in experimental models. The aim of this study was to investigate the distribution of angiotensin converting enzyme (ACE), angiotensinogen (AGT) and angiotensin receptor type 1 (ATR1) genetic polymorphisms in children affected by chronic renal failure due to renal hypodysplasia associated with posterior urethral valves or without urethral abnormalities.. The study included 50 children (21 with hypodysplasia associated with PUVs, 7 with obstructive uropathy and 22 with pure hypodysplasia) and 50 healthy subjects matched for sex and geographic origin. ACE ID, AGT TC and ATR1 AC gene polymorphisms were assayed in all patients with standard polymerase chain reaction techniques.. ACE II was expressed more in patients with PUVs compared to those with other dysplasias and controls (43% vs 7% and 10%, respectively, chi-square test p <0.05), while ATR1 AA was significantly less represented in patients with hypodysplasia compared to controls (38% vs 56%, chi-square test p <0.05). ACE DD and AGT genotypes were not distributed differently in patients with PUVs compared to those with other dysplasias and controls.. To our knowledge this is the first report associating severe congenital uropathies and renal hypodysplasia with decreased renin-angiotensin system activity associated with the ACE II genotype and a possible functional imbalance among ATR1 receptors.

Topics: Angiotensin II; Angiotensinogen; Child; Chromosome Deletion; Female; Genetic Variation; Genotype; Humans; Kidney Failure, Chronic; Male; Odds Ratio; Peptidyl-Dipeptidase A; Polymorphism, Genetic; Receptor, Angiotensin, Type 1; Renin-Angiotensin System; Urethra

Polymorphisms of renin-angiotensin system (RAS) genes in patients with end-stage renal disease (ESRD) on chronic hemodialysis may be associated with QTc interval prolongation, leading to fatal arrhythmias. The objective of this study was to determine (1) the prevalence of QTc prolongation in hemodialysis patients, and (2) the association of a prolonged QTc in these patients with RAS polymorphisms [angiotensin-converting enzyme-insertion/deletion (ACE-I/D), angiotensin type 1 receptor-A1166C (AT1R-A1166C), and angiotensinogen-M235T (AGT-M235T)].. Twelve-lead electrocardiograms (ECGs), serum electrolytes (sodium, potassium, and calcium), and ACE and angiotensin II levels were obtained 10 to 12 hours after a hemodialysis session in 43 patients with ESRD on chronic hemodialysis [mean age (+/-SD), 55 +/- 14 years]. Using polymerase chain reaction (PCR), the presence of polymorphisms of the ACE-I/D, AT1R-A1166C, and AGT-M235T genes was determined from the buccal cells. A maximum QT interval in patients with sinus rhythm and normal QRS duration was corrected for heart rate using Hodges' formula.. Fifty-eight percent of the patients had QTc interval prolongation (>440 msec). The ACE-DD genotype (P = 0.002) and the C allele of the AT1R-A1166C gene (P = 0.004), but not the AGT-M235T gene, contributed to QTc prolongation.. Polymorphisms of ACE and AT1R genes additively contribute to QTc prolongation found in a great majority of ESRD patients. Therefore, ESRD patients with both or one of these polymorphisms may be at a higher risk for sudden cardiac death.

Topics: Adult; Aged; Angiotensinogen; Death, Sudden, Cardiac; Female; Genetic Predisposition to Disease; Humans; Kidney Failure, Chronic; Long QT Syndrome; Male; Middle Aged; Peptidyl-Dipeptidase A; Polymorphism, Genetic; Prevalence; Receptor, Angiotensin, Type 1; Renal Dialysis; Renin-Angiotensin System; Risk Factors

We studied the angiotensin-converting enzyme (ACE), angiotensinogen (AGT), and angiotensin II type 1 receptor (AT1R) gene polymorphisms for association with susceptibility to primary vesicoureteral reflux (VUR) and disease progression in 74 Taiwanese children, including 16 with end-stage renal disease (ESRD), and 117 normal controls. Polymerase chain reaction-amplified products containing the ACE gene T-5491C, A-5466C, T-3892C, A-3692C, A-240T, Alu I/D, the AGT gene C-532T, G-217A, G-152A, A-20C, A-6G, T174M, T235M, and the AT1R gene A-1138T, T-810A, T-713G, C-521T, AG-214CC, A-153G, A1166C polymorphisms were analyzed by restriction enzyme digestion, gel electrophoresis, or single-strand conformation polymorphism analysis. All the polymorphisms examined were in Hardy-Weinberg equilibrium. The strong non-random association within the ACE, AGT, and AT1R genes suggests low levels of intragenic recombination. None of these polymorphisms showed association with VUR susceptibility. However, the allele frequency distribution of the six ACE polymorphisms among primary VUR patients with or without ESRD was statistically different. The linked ACE T-A-T-A-A-I allele was observed significantly more frequently in VUR children with ESRD (P<0.001). A significant increase of left ventricular mass index was also found in the linked ACE T-A-T-A-A-I allele group compared with the non-ACE T-A-T-A-A-I allele group of patients aged 18 years with renal progression. The AGT A-6G genotype frequencies were significantly different when the analysis was stratified by genotype of the ACE polymorphisms. The data showed that ACE gene polymorphisms were associated with progressive renal deterioration in Taiwanese children with VUR and might act synergistically with the -6 G allele of the AGT gene.

Topics: Adolescent; Adult; Angiotensinogen; Child; Disease Progression; DNA Primers; Female; Gene Frequency; Genetic Predisposition to Disease; Humans; Kidney Failure, Chronic; Linkage Disequilibrium; Male; Peptidyl-Dipeptidase A; Polymerase Chain Reaction; Polymorphism, Genetic; Polymorphism, Single-Stranded Conformational; Receptor, Angiotensin, Type 1; Renin-Angiotensin System; Taiwan; Uremia; Vesico-Ureteral Reflux

Gene polymorphisms in angiotensin-converting enzyme (ACE), angiotensinogen (AGT) and angiotensin II type 1 receptor (ATR) had been associated with IgA nephropathy (IgAN) and its progression. Several studies on Caucasian and Japanese had reported contradicting results. We determined these polymorphisms in 118 Chinese patients with IgAN and 94 healthy Chinese to assess their clinical impact.. Genotyping was performed with DNA from peripheral leukocytes, PCR amplification of the polymorphic sequence, restriction enzymes digestion, separation and identification of DNA fragments. Clinical data at renal biopsy and final status on renal function were determined from patients' records.. Among controls, genotype distributions were in Hardy-Weinberg equilibrium. Comparing all IgAN patients with controls, AGT and ATR genotype distributions were similar whereas there was significant increase in the ACE DD genotype (p < 0.05). Comparing patients with end-stage renal failure (IgAN-ESRF) and without (IgAN-nonESRF), there was no difference in any of the three gene polymorphisms. But in contrast, there were significant differences in higher male prevalence (p < 0.05), increased serum creatinine at presentation (p < 0.05), more sclerosis (p < 0.01) and higher tubulointerstitial lesion score (p < 0.001) in the IgAN-ESRF group.. Among the ACE, AGT and ATR gene polymorphisms, only the DD genotype may predispose the individual to IgAN in our Chinese population. In contrast to clinical and histological risk factors, these genetic variations showed no impact on disease progression to ESRF. It is unlikely that genotyping more patients will prove these genes useful. Nevertheless, preclinically determined genetic markers are very useful as risk factors for disease occurrence and as prognostic indices for disease progression. Therefore, continuing efforts should be made to look at other genes to find those with significance.

Topics: Adult; Angiotensinogen; China; Disease Progression; Female; Genetic Predisposition to Disease; Glomerulonephritis, IGA; Humans; Kidney Failure, Chronic; Male; Middle Aged; Peptidyl-Dipeptidase A; Polymorphism, Genetic; Receptor, Angiotensin, Type 1; Renin-Angiotensin System; Singapore

Glomerular filtration rate decline (GFRd) is variable in autosomic dominant polycystic kidney disease (ADPKD). In 88 ADPKD patients, GFRd was assessed by 1/S(Cr) and compared with the association to AT1A1166C (AT1R), AGTM235T (angiotensinogen) and ecNOSGlu298Asp (NO endothelial synthase) polymorphisms. Age at S(Cr) values of 2 and 6 mg/dl were assumed as beginning of progressive phase (A2) and end-stage-renal disease (A6), respectively. Polymorphisms were studied by PCR-RFLP. The group as a whole showed GFRd (ml/min/year) of 6.9+/-0.5; A2 and A6 of 48.9+/-1.3 and 55.0+/-1.4 years and mean arterial pressure of 111.2+/-1.2 mmHg. When A6 was considered, two populations were defined (< or = and > 55 years). In < or = 55 (assumed as PKD1 phenotype) (n=42), A2 and A6 of the AT1 1166CC genotype were 36.0+/-1.2 and 41.4+/-0.9 years vs AA-AC (42.8+/-1.0 and 47.5+/-0.8, p<0.001). A2 and A6 of the ecNOS298Asp/Asp genotype were 34.8+/-1.5 and 41.1+/-0.6 years vs. Glu/Glu-Glu/Asp (42.4+/-0.9 and 47.1+/-0.8, p<0.02). In AGT235TT genotype, GFRd was 12.4+/-2.2 ml/min/year vs MM-MT (7.9+/-0.7, p<0.03). This difference was also observed when all ADPKD patients were considered (TT: 11.02+/-1.5 vs. MM-MT: 6.44+/-0.5 ml/ min/year, p<0.003). AT1 1166CC and ecNOS 298Asp/Asp are associated with earlier A2 and A6 whereas AGT 235TT induce twofold increase in GFRd, suggesting that RAS and ecNOS are involved in ADPKD progression.

Topics: Adult; Angiotensinogen; Animals; Disease Progression; Genotype; Glomerular Filtration Rate; Humans; Kidney Failure, Chronic; Mice; Middle Aged; Nitric Oxide; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Nitric Oxide Synthase Type III; Phenotype; Polycystic Kidney, Autosomal Dominant; Polymorphism, Genetic; Regression Analysis; Renin-Angiotensin System

Genetic polymorphisms of the angiotensinogen (AGT) and angiotensin-converting enzyme (ACE) genes are associated with increased risk of hypertension and left ventricular hypertrophy (LVH) in hypertensive subjects. However, the extent to which these polymorphisms are related to LVH and remodeling in dialysis patients remains unknown.. Two hundred and forty-six end-stage renal disease (ESRD) patients on peritoneal dialysis and 183 control subjects, all of Chinese origin, were genotyped for the ACE insertion/deletion (I/D) and the AGT M235T gene polymorphisms. Left ventricular mass index (LVMi) and relative wall thickness were measured using echocardiography.. Prevalence of ACE DD and AGT TT genotype was 14% and 83%, respectively, in ESRD patients and did not differ significantly from controls. A total percentage of 95% of our patients had LVH (171 with concentric and 63 with eccentric hypertrophy). Adjusting for age, gender, body mass index, duration of dialysis, diabetes, renal diagnosis, hematocrit, systolic and diastolic blood pressure, dialysis urea clearance, residual glomerular filtration rate, and use of converting enzyme inhibitors or angiotensin receptor blockers, AGT TT genotype remained independently associated with greater LVMi (coefficient = 28.73; 95% CI, 5.72 to 51.75; P = 0.015) and relative wall thickness (coefficient = 0.072; 95% CI, 0.022 to 0.122; P = 0.005) than MT/MM genotypes. LVMi and relative wall thickness did not differ significantly among patients with DD, DI, and II genotypes. No statistical significant interaction was noted between ACE and AGT gene polymorphism in relation to LVMi and relative wall thickness.. Polymorphism of the AGT M235T gene but not ACE I/D gene is associated with greater LVMi and relative wall thickness, indicating more concentric LVH, in Chinese peritoneal dialysis patients. Possible synergistic effects between AGT and ACE gene polymorphism require further evaluation in a larger population.

Topics: Adult; Angiotensinogen; Asian People; Echocardiography; Female; Genotype; Heart Ventricles; Humans; Hypertrophy, Left Ventricular; Kidney Failure, Chronic; Male; Middle Aged; Myocardium; Peptidyl-Dipeptidase A; Peritoneal Dialysis; Polymorphism, Genetic; Prevalence; Ventricular Remodeling

This study compared the polymorphisms of angiotensin-converting enzyme (ACE), angiotensinogen (AGT) and angiotensin II type 1 receptor (AT1R) gene between type II diabetes with diabetic nephropathy (DN) in end-stage renal disease (ESRD) and those of the normal individuals in Taiwan.. 129 patients with type II diabetes in ESRD from three dialysis centers were compared to 116 age and blood pressure-matched normal individuals. Polymerase chain reaction (PCR) specific for ACE gene was tested for insertion/deletion polymorphism. M235T and T174M variant polymorphisms of the AGT gene and the AT1R A1166C polymorphism were also tested according to previously described protocols.. Between the two groups, frequencies of the alleles and the genotypes in ACE gene polymorphism were comparable. There was no significant difference of the ACE insertion and deletion polymorphism and AT1R gene polymorphism between the two groups. The allele frequencies of AGT point mutation at 235 (M235T) was significantly higher in DM nephropathy but the genotypic frequencies were not. In the AGT point mutation at 174 (T174M), the frequencies of both of alleles and genotypes were significantly higher in the DM nephropathy patients.. In conclusion, there were significantly higher frequencies of alleles and genotypes in AGT point mutation at 174, which had never been reported before. In AGT point mutation at 235, there were significantly higher frequencies of alleles, but not genotypes in diabetic nephropathy. Our study suggested that the AGT gene plays an important role in diabetic nephropathy.

Topics: Adult; Aged; Angiotensinogen; Diabetes Mellitus, Type 2; Diabetic Nephropathies; Female; Humans; Kidney Failure, Chronic; Male; Middle Aged; Peptidyl-Dipeptidase A; Polymorphism, Genetic; Receptor, Angiotensin, Type 1; Receptors, Angiotensin

Autosomal dominant polycystic kidney disease (ADPKD), a common genetic disease, is characterized by the development of hypertension and end stage renal disease. An increase in the activity of the renin-angiotensin system, due to a renal ischemia caused by cyst expansion, contributes to the development of hypertension and renal failure in ADPKD. Recently, the angiotensinogen (AGT) gene, M235T, and angiotensin II type 1 receptor (ATR) gene, A1166C, polymorphisms have been associated with the susceptibility to develop hypertension and renal disease. We hypothesized that the AGT M235T and ATR A1166C polymorphisms could account for some of the variability in the progression of ADPKD. Genotyping was performed in 108 adult patients with ADPKD, and 105 normotensive healthy controls, using PCR and restriction digestion. We analyzed the effects of the AGT M235T and ATR A1166C polymorphisms on hypertension and age at the end stage renal disease (ESRD). Of the 108 patients with ADPKD, 64 (59%) had hypertension and 24 (22%) reached the ESRD. The prevalence of hypertension were; [MM+MT], [TT] genotypes, 60%, 59% (p=1.00); [AA], [AC+CC] genotypes, 60%, 50% respectively (p=0.54). The ages at the onset of ESRD were; [MM+MT], [TT] genotypes, 50 +/- 9 years, 56 +/- 8 years (p=0.07); [AA], [AC+CC] genotypes, 54 +/- 8 years, 52 +/- 14 years, respectively (p=0.07). There were no differences in the prevalence of hypertension and the ages at the ESRD in relation to the AGT M235T and ATR A1166C polymorphisms. We suggest that the AGT and ATR gene polymorphisms would not have an effect on hypertension or the ESRD in ADPKD.

Topics: Adult; Age of Onset; Angiotensinogen; Disease Progression; Female; Humans; Hypertension; Kidney Failure, Chronic; Male; Middle Aged; Polycystic Kidney, Autosomal Dominant; Polymorphism, Genetic; Prevalence; Receptor, Angiotensin, Type 1; Receptors, Angiotensin

The impact of polymorphisms in the genes coding for angiotensinogen (M235T), ACE (ID), and angiotensin II type 1 receptor (A(1166)-->C) on decline in GFR and doubling of s-creatinine or development of ESRD in patients with type 1 diabetes and diabetic nephropathy (DN) was tested. From 1985, all patients (n = 169) who had established diabetic nephropathy and were treated with angiotensin-converting enzyme inhibition (ACE-I) were identified consecutively at Steno Diabetes Center. Patients were followed for a median of 6 yr (range, 3 to 15 yr), with nine (range, three to 29) measurements of GFR ((51)Cr-EDTA). In a Cox proportional hazards model corrected for other risk factors, the D allele (ACE/ID) was associated with time to doubling of s-creatinine/ESRD (rate ratio, 1.81 per allele; 95% confidence interval, 1.09 to 3.03; P = 0.02). A new interaction hypothesis was generated demonstrating that the following variables were associated with accelerated decline in GFR: albuminuria (estimate, 2.12 ml/min per yr per 10-fold increase in albuminuria; P < 0.001), mean BP (estimate, 0.88 ml/min per yr per 10 mmHg; P = 0.02), hemoglobin A(1c) (estimate, 0.54 min/min per yr per 1%; P = 0.02), and number of M (M235T)/D (ID)/A (A(1166)-->C) alleles (estimate, 0.45 ml/min per yr per allele; P = 0.049). Number of M/D/A alleles also influenced time to doubling of s-creatinine or ESRD. In this study of patients with type 1 diabetes, the D allele of the ACE/ID polymorphism in addition to nongenetic risk factors independently accelerated progression of DN during ACE-I. Interaction between polymorphisms in the renin-angiotensin system also influenced the loss of kidney function. This new genetic interaction model needs to be confirmed in future studies.

Topics: Adult; Angiotensin-Converting Enzyme Inhibitors; Angiotensinogen; Creatinine; Diabetes Mellitus, Type 1; Diabetic Nephropathies; Female; Follow-Up Studies; Glomerular Filtration Rate; Humans; Kidney Failure, Chronic; Male; Middle Aged; Peptidyl-Dipeptidase A; Polymorphism, Genetic; Receptor, Angiotensin, Type 1; Renin-Angiotensin System; Time Factors

A genetic susceptibility to hypertension may predispose to the development of end-stage renal disease (ESRD) and promote a more rapid loss of renal function in patients with renal diseases. The alpha-adducin (ADD) gene, alone or in combination with the angiotensinogen (AGT) and the angiotensin-converting enzyme (ACE), is a candidate for abnormal blood pressure regulation and thus for increased susceptibility or faster progression to ESRD.. Genotyping for the G460W-ADD, M235T-AGT and the insertion/deletion (I/D)-ACE gene polymorphisms was performed in 260 control subjects and 260 ESRD patients using polymerase chain reaction, gel analysis and appropriate restriction digest.. The frequencies of the ADD, AGT and ACE genotypes in ESRD patients did not differ from observed frequencies in control subjects. The average (+/-SE) time from diagnosis to the onset of ESRD tended to be shorter in the presence of the ADD-460WW (5.1 +/- 1.1 years, N = 10) than with the GW (9.9 +/- 0.7 years, N = 81) and GG (11.3 +/- 1.0 years, N = 164) genotypes (F-ratio=2.71, P = 0.068; WW vs. GW P < 0.06 and vs. GG <0.03). In the 167 patients homozygous for the ADD-G allele, a more rapid progression with the ACE-DD genotype as compared to ACE-DI and II was found (P < 0.02).. The ADD genotype is predictive of the course of renal function loss in an unselected renal population and influences the effect of the ACE genotype to modulate the rate of progression to ESRD. Thus, the ADD genotype may play a role for the understanding of interindividual differences in the course of renal diseases.

Topics: Adult; Aged; Angiotensinogen; Calmodulin-Binding Proteins; Disease Progression; Female; Gene Frequency; Genotype; Homozygote; Humans; Kidney Failure, Chronic; Male; Middle Aged; Peptidyl-Dipeptidase A; Prognosis; Reference Values; Time Factors

Hypertension contributes to the progression to renal failure. A genetic susceptibility to hypertension may predispose to the development of end-stage renal disease (ESRD) and promote a more rapid progression to ESRD in patients with renal diseases. Genes encoding for angiotensinogen (AGT), angiotensin-converting enzyme (ACE), and aldosterone synthase (CYP11B2) are candidates for abnormal blood pressure regulation.. Genotyping was performed in 327 control subjects and 260 ESRD patients for the M235T-AGT, the insertion/deletion (I/D)-ACE, and the -344T/C-CYP11B2 gene polymorphisms using polymerase chain reaction, gel analysis, and appropriate restriction digest when required.. Genotype frequencies did not differ significantly between ESRD patients and controls. When ESRD diabetic subjects were compared with diabetic patients without nephropathy, the prevalence of the AGT-MM genotype was lower (28.1 vs. 52.8%, P < 0.01), while the AGT-TT genotype was higher (15.6 vs. 2.7%, P < 0.05). The AGT-TT genotype was associated with a faster progression to ESRD in patients with glomerulonephritis (P < 0.05). In the total ESRD population, progression of renal disease was faster with the ACE-DD than with the DI and II alleles (P < 0.05). This association was particularly strong when the interaction with the AGT genotype was analyzed, with a rapid progression in ACE-DD as compared with ACE-DI and II in patients with the AGT-MM genotype (P < 0.01).. Susceptibility for ESRD and faster progression to ESRD are linked with the AGT genotype in diabetic patients. Faster progression to ESRD is associated with the ACE genotype when the total population with ESRD and with the AGT genotype when patients with glomerulonephritis are considered. Thus, genes of the renin-angiotensin-aldosterone system are candidate genes for further understanding of the interindividual differences in the development and course of ESRD.

Topics: Adult; Aged; Angiotensinogen; Cytochrome P-450 CYP11B2; Diabetes Mellitus; Diabetic Nephropathies; Disease Progression; Female; Gene Frequency; Genetic Predisposition to Disease; Genotype; Glomerulonephritis; Humans; Kidney Failure, Chronic; Male; Middle Aged; Peptidyl-Dipeptidase A; Polymorphism, Genetic; Reference Values; Renin-Angiotensin System; Time Factors

Glomerulonephritis is a group of diseases with complex etiology, pathogenesis, morphological features and clinical course. The renin-angiotensin system genes are important group of candidate genes involved in pathogenesis of chronic renal diseases. The purpose of our study was to analyze the association of genetic polymorphisms of these genes with glomerular kidney diseases. The study population consisted of 52 patients with immunological glomerular kidney diseases and 50 hemodialyzed patients with end-stage renal failure with glomerulonephritis as primary disease. The control group consisted of 200 healthy subjects. By means of the polymerase chain reaction (PCR) the following polymorphisms were evaluated: insertion/deletion (I/D) polymorphism in intron 16 of the angiotensin-converting enzyme gene (ACE), M235T polymorphism of the angiotensinogen gene (AGT) and A1166C polymorphism of the angiotensin II type 1 receptor gene (AT1R). No significant association was found between the ACE allele and genotype frequencies and the disease. The allele frequency of the M235T polymorphism was different from that observed in the control group, but differences in the genotype distribution were not statistically significant. The CC genotype of the AT1R gene polymorphism was significantly more frequent in patients than controls. This suggests an increased susceptibility to renal diseases in individuals carrying the CC genotype. This relationship is not associated with hypertension. Our results suggest that in the Polish population the AT1R gene polymorphism might be associated with increased susceptibility to chronic renal diseases.

Topics: Adult; Angiotensinogen; Case-Control Studies; Female; Glomerulonephritis; Humans; Kidney Failure, Chronic; Male; Middle Aged; Peptidyl-Dipeptidase A; Polymerase Chain Reaction; Polymorphism, Genetic; Receptor, Angiotensin, Type 1; Receptors, Angiotensin; Renin-Angiotensin System

Chronic renal failure (CRF) is a complex phenotype that results from an underlying kidney disease and superimposing environmental and genetic factors. The aim of our study was to evaluate the role of polymorphisms in the genes encoding for components of the renin-angiotensin system (RAS) in the development and/or progression of CRF.. Two hundred forty-seven family trios (patients with CRF and both parents; 120 with primary chronic glomerulonephritis, 80 with interstitial nephritis, and 47 with type 1 diabetes with nephropathy) were examined, and transmission/disequilibrium test (TDT) was used to evaluate allele transmission from heterozygous parents to affected offspring.. The D allele of the angiotensin I-converting enzyme (ACE) gene insertion/deletion polymorphism was transmitted significantly more frequently than expected for no association among all examined trios and in the subgroup of patients with interstitial nephritis. The angiotensinogen 235T allele was transmitted significantly more frequently to patients with CRF than expected for no association, but the effect was seen only in patients with interstitial nephritis. The presence of the DD or ID genotype was associated with a faster rate of decline of renal function, which was not observed for the angiotensinogen M235T polymorphism. For chymase gene and angiotensin II receptor type 1 gene, allele transmission did not deviate significantly from a random proportion of 50:50%.. The results of this study suggest that ACE gene insertion/deletion and angiotensinogen M235T polymorphisms contribute to the increased risk for the development of CRF, but the magnitude of the effect within subsets of patients with specific etiologies of CRF must be evaluated further.

Topics: Adolescent; Adult; Alleles; Angiotensinogen; Creatinine; Family Health; Female; Gene Deletion; Genetic Predisposition to Disease; Genotype; Humans; Kidney Failure, Chronic; Male; Nephritis, Interstitial; Peptidyl-Dipeptidase A; Polymorphism, Single Nucleotide; Risk Factors

Statins are effective in prevention of end-organ damage; however, the benefits cannot be fully explained on the basis of cholesterol reduction. We used an angiotensin II (Ang II)-dependent model to test the hypothesis that cerivastatin prevents leukocyte adhesion and infiltration, induction of inducible nitric oxide synthase (iNOS), and ameliorates end-organ damage.. We analyzed intracellular targets, such as mitogen-activated protein kinase and transcription factor (nuclear factor-kappaB and activator protein-1) activation. We used immunohistochemistry, immunocytochemistry, electrophoretic mobility shift assays, and enzyme-linked immunosorbent assay techniques. We treated rats transgenic for human renin and angiotensinogen (dTGR) chronically from week 4 to 7 with cerivastatin (0.5 mg/kg by gavage).. Untreated dTGR developed hypertension, cardiac hypertrophy, and renal damage, with a 100-fold increased albuminuria and focal cortical necrosis. dTGR mortality at the age of seven weeks was 45%. Immunohistochemistry showed increased iNOS expression in the endothelium and media of small vessels, infiltrating cells, afferent arterioles, and glomeruli of dTGR, which was greater in cortex than medulla. Phosphorylated extracellular signal regulated kinase (p-ERK) was increased in dTGR; nuclear factor-kappaB and activator protein-1 were both activated. Cerivastatin decreased systolic blood pressure compared with untreated dTGR (147 +/- 14 vs. 201 +/- 6 mm Hg, P < 0.001). Albuminuria was reduced by 60% (P = 0.001), and creatinine was lowered (0.45 +/- 0.01 vs. 0.68 +/- 0.05 mg/dL, P = 0. 003); however, cholesterol was not reduced. Intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 expression was diminished, while neutrophil and monocyte infiltration in the kidney was markedly reduced. ERK phosphorylation and transcription factor activation were reduced. In addition, in vitro incubation of vascular smooth muscle cells with cerivastatin (0.5 micromol/L) almost completely prevented the Ang II-induced ERK phosphorylation.. Cerivastatin reduced inflammation, cell proliferation, and iNOS induction, which led to a reduction in cellular damage. Our findings suggest that 3-hydroxy-3-methylglutaryl coenzyme (HMG-CoA) reductase inhibition ameliorates Ang II-induced end-organ damage. We suggest that these effects were independent of cholesterol.

Topics: Albuminuria; Angiotensin II; Angiotensinogen; Animals; Animals, Genetically Modified; Blood Pressure; Cell Division; Cholesterol; Creatinine; Disease Models, Animal; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Intercellular Adhesion Molecule-1; Kidney; Kidney Failure, Chronic; Leukocytes; Male; Mitogen-Activated Protein Kinases; NF-kappa B; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Organ Size; Phosphorylation; Plasminogen Activators; Pyridines; Rats; Rats, Sprague-Dawley; Renin; Thromboplastin; Transcription Factor AP-1; Urea; Vascular Cell Adhesion Molecule-1; Vasoconstrictor Agents

The impact of renin-angiotensin system (RAS) gene polymorphism on the prognosis of IgA nephropathy (IgAN) is still debated. A longitudinal study of renal prognosis in patients with IgAN was conducted to search retrospectively for a genotype-phenotype association between RAS polymorphisms and end-stage renal failure (ESRF). A classification based on serum creatinine (S(cr)) and 24-h proteinuria (24-P) measured at the time of renal biopsy was used to estimate the risk of ESRF in IgAN: stage 1 (S(cr) 150 micromol/L and 24-P < 1 g or S(cr) < or = 150 micromol/L and 24-P > or = 1 g), stage 3 (S(cr) > 150 micromol/L and 24-P > or = 1 g). Deletion/insertion polymorphism (D/I) of the angiotensin I converting enzyme gene, M235T polymorphism (T/M) of the angiotensinogen gene and A1166C polymorphism (C/A) of the angiotensin II type 1 receptor gene were determined in 274 Caucasian men with biopsy-proven IgAN (n = 86, 112, and 76 in stages 1, 2, and 3, respectively). Mean global follow-up was 6 +/- 5 yr after renal biopsy. For stages 1, 2, and 3, ESRF developed in 7 (8. 1%), 39 (34.8%), and 49 (64.4%) cases (P: < 0.0001), 11.7 +/- 4, 5.4 +/- 4, and 2 +/- 2 yr, respectively, after renal biopsy (P: < 0.001). The distributions of the three genotypes into the three stages were similar. Different distributions were observed when patients were grouped by stage and genotype: ID+DD: 72% in stage 1 versus 84.6% in stages 2 + 3 (P: = 0.02; kappa = 0.14); MT+TT: 66.2% in stages 1 + 2 versus 78.9% in stage 3 (P: = 0.04; kappa = 0.09); and AA+AC: 89.9% in stages 1 + 2 versus 97.4% in stage 3 (P: = 0.04; kappa = -0.1). However, with the use of the Cox proportional hazard model, none of the three genotypes was found to have predictive value for renal survival. Compared with S(cr) and 24-P, genotypes DD, TT, and AA are unlikely to serve as clinically useful predictors of ESRF in IgAN.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Angiotensinogen; Child; Genotype; Glomerulonephritis, IGA; Humans; Kidney Failure, Chronic; Longitudinal Studies; Male; Middle Aged; Peptidyl-Dipeptidase A; Polymorphism, Genetic; Predictive Value of Tests; Receptor, Angiotensin, Type 1; Receptor, Angiotensin, Type 2; Receptors, Angiotensin; Retrospective Studies; Survival Analysis

The factors that initiate chronic renal failure in patients with hypertension, diabetes mellitus, and chronic glomerular disease are largely unknown. The likely genetic contribution to ESRD, particularly in African Americans, suggests that linkage analysis may be useful to evaluate the role of candidate genes in the pathogenesis of chronic renal failure. The renin-angiotensin-aldosterone (RAA) axis has been intensively evaluated for its contribution to cardiovascular disease and nephropathy. This study tested for linkage between candidate genes in the RAA axis and chronic renal failure, using 85 African-American sibling pairs (from 65 families) concordant for ESRD. Angiotensinogen was selected because of the putative link between it and mild to moderate essential hypertension and nephrosclerosis; angiotensin-converting enzyme because of its possible contribution to diabetic nephropathy; and renin, the angiotensin II receptor, and kallikrein because of their roles in hypertension and renal perfusion. These candidate loci did not demonstrate linkage to either diabetic or nondiabetic renal disease in this study's collection of sibling pairs. These results suggest that polymorphisms at these RAA axis loci do not make major contributions to the pathogenesis of renal disease in African Americans.

Topics: Angiotensinogen; Black People; Diabetes Complications; Family; Female; Genetic Linkage; Humans; Hypertension; Kidney Failure, Chronic; Male; Peptidyl-Dipeptidase A; Polymorphism, Genetic; Receptors, Angiotensin; Renin; Renin-Angiotensin System

Renin activity appears to be present in low concentrations in the plasma of anephric humans but could be artifactual secondary to inadvertent activation of prorenin during specimen collection and handling or from a renin-like enzyme. We studied the effects of specimen collection, storage, different assay conditions, trypsin activation, and the renin inhibitor EMD 56133 (E Merck, Darmstadt) on plasma renin activity (PRA) in anephric man. PRA was detectable in all seven bilaterally nephrectomized (BNX) patients (0.2 +/- 0.1 ng AI/ml/hr, range 0.1-0.7) but was significantly lower than normals (2.4 +/- 0.3 ng AI/ml/hr, range 1.5-3.1, p = 0.001). PRA was not different in BNX whether blood samples were collected on ice or at room temperature and assayed immediately or whether samples were frozen and assayed several days later. Prolonged cold storage of samples and five freeze-thaw cycles over six to seven months did not significantly increase PRA in normals or anephrics. However, deliberate repeated freezing and thawing over the period of a single day increased PRA 4.1-fold in BNX and 1.6-fold in normals. Renin-like activity was also detected in BNX individuals using renin concentration determinations with either excess human or sheep angiotensinogen. The inhibition of renin activity (IC-50% = 3.16 x 10(-9) molar) by EMD 56133 was not different between BNX and normals. Thus, active renin is present in the plasma of anephric humans and does not result from the inadvertent activation of prorenin due to sample handling. Although the source of PRA in BNX is unknown, the enzyme appears functionally normal as evidenced by the dose-response to a single renin inhibitor.

Topics: Adult; Angiotensin I; Angiotensinogen; Enzyme Activation; Enzyme Precursors; Female; Humans; Kidney Failure, Chronic; Male; Middle Aged; Nephrectomy; Oligopeptides; Renal Dialysis; Renin; Trypsin

Most of the 52 patients on maintenance dialysis investigated in this study suffered from arterial hypertension in spite of efforts to reduce 'dry weight'. In this situation we found that the majority of patients were underweight and that total body water, extracellular volume and blood volume were close to normal when related to reference systems consisting of height and age. Hypertensive patients were not volume expanded as compared to normotensive patients and controls. Plasma renin activity and angiotensin II were elevated in a few patients, with a trend to higher levels in the more hypertensive patients. Various approaches attempting to correlate blood pressure and the respective volume-renin factors did not prove to be conclusive in explaining the maintenance of hypertension in chronic renal failure on the basis of the sodium-renin feedback.

Topics: Adult; Aged; Angiotensin II; Angiotensinogen; Blood Pressure; Body Fluid Compartments; Body Water; Body Weight; Extracellular Space; Female; Humans; Kidney Failure, Chronic; Male; Middle Aged; Renin