Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011881 (diabetic nephropathy)
 10,836 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Increased activity of the renin-angiotensin system has been implicated in decreased, long-term survival of renal allografts. Recent studies suggest that a deletion variant of the angiotensin-converting enzyme, associated with increased humoral and tissue activity of this enzyme, is a risk factor for the development of diabetic nephropathy and the progression of IgA nephropathy. To determine whether the deletion variant of the angiotensin-converting enzyme gene influences the long-term outcome in renal transplant recipients, the relationship between donor and recipient angiotensin-converting enzyme genotype and clinical outcome were examined over a follow-up period up to 30 mo in a cohort of 269 Caucasian patients undergoing kidney transplantation between 1988 and 1993. In a subsequent case control study, the frequencies of the angiotensin-converting enzyme genotype were compared in a group of Caucasian patients with a graft survival of less than 3 yr (mean survival, 11 mo; n = 328) with the frequencies in patients with a graft survival of at least 3 yr (mean survival, 65 mo, n = 461). Neither in the cohort nor in the case control study was there a significant effect of recipient or donor angiotensin-converting enzyme genotype on transplant survival. Furthermore, the frequency of the angiotensin-converting enzyme deletion allele both in recipients and donors was similar to that reported in Caucasian controls. This study, therefore, does not support the hypothesis that the recipient or donor angiotensin-converting enzyme insertion/deletion polymorphism is an important determinant of transplant survival in Caucasian patients undergoing renal transplantation.
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PMID:Angiotensin-converting enzyme genotype and renal allograft survival. 925 61

Classically, the renin-angiotensin system (RAS) in diabetes was thought to be suppressed, and relatively unimportant in the regulation of hemodynamics and the development of complications. However, recent developments have caused reconsideration of this notion. Studies of pharmacological interruption of the RAS with angiotensin converting enzyme (ACE) inhibition have implicated this hormonal system in the progression of diabetic nephropathy, both experimentally and clinically. Preliminary evidence also suggests a beneficial effect of angiotensin II (ANG II) receptor antagonists. The relative roles of the systemic versus intrarenal RAS in the pathogenesis of diabetic nephropathy have recently been evaluated. Although plasma renin level is generally low, it is not yet clear whether RAS component processing is normal in diabetes; there may be subtle changes in ANG II metabolism that sustain relatively higher plasma ANG II levels. Furthermore, the intrarenal RAS may not be suppressed. Renal renin levels tend to be disproportionately elevated, as compared with plasma renin values. Renal ANG II levels are normal, and renal mRNAs for RAS components have been variable. In general, lack of RAS suppression (despite plasma volume and increased exchangeable sodium) may indicate inappropriate activity of the RAS in diabetes. RAS-mediated injury may occur via stimulation of a number of sclerosing mediators, and there is evidence that hyperglycemia acts synergistically with ANG II to promote cellular injury. Finally, various RAS candidate genes for development of diabetic nephropathy have been examined and, although controversy remains, ACE gene polymorphisms may be involved. Together, these recent investigations lend further support to the notion that the RAS plays an important role in diabetic nephropathy, and are beginning to shed light on the mechanisms of progressive renal injury.
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PMID:Role of angiotensin II in diabetic nephropathy. 931 12

Several observations suggest that inherited factors are influential in the development of nephropathy in patients with insulin-dependent diabetes mellitus (IDDM). Genetic components of the renin angiotensin system are possible candidate genes. The aim of this study was to determine the role of the hypertension associated angiotensin II type 1 receptor (AT1R) gene A1166C polymorphism in susceptibility to nephropathy in IDDM. We examined 264 Caucasoid patients with IDDM and overt nephropathy (as defined by persistent proteinuria in the absence of other causes, hypertension and retinopathy), 136 IDDM patients with long duration of diabetes and no nephropathy (LDNN group), 200 recently diagnosed IDDM patients (Sporadic Diabetic group), and 212 non-diabetic subjects. The AT1R gene polymorphism was assessed using the polymerase chain reaction and restriction isotyping. Genotype frequencies did not differ significantly between the sporadic diabetic group and the nephropathy group (p = 0.245), nor between the long duration non-nephropathy group and the nephropathy group (p = 0.250). Allele frequencies were not significantly different between the three groups (p = 0.753). We conclude that there is no significant association between the hypertension associated AT1R gene polymorphism and diabetic nephropathy in patients with IDDM in the UK.
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PMID:Lack of association of angiotensin II type 1 receptor gene polymorphism with diabetic nephropathy in insulin-dependent diabetes mellitus. 937 75

The renal kallikrein-kinin system and the renin-angiotensin system are implicated in the pathogenesis of diabetic nephropathy. We have shown that renal kallikrein and renin gene expression are altered by diabetes. To investigate the cellular mechanisms responsible for these changes, we examined the effects of acute insulin and insulin-like growth factor I (IGF-I) treatment on renal kallikrein-kinin and renin-angiotensin system components. Three weeks after induction of diabetes, we measured renal kallikrein and renin mRNA levels, renal kallikrein and renal renin activity, and plasma renin activity in control and diabetic rats and diabetic rats treated with insulin or IGF-I for 2 or 5 h. In diabetic rats, kallikrein and renin mRNA levels were reduced >50% compared with control rats. Renal tissue kallikrein levels and plasma renin activity were decreased, whereas renal renin content was unchanged. Insulin increased kallikrein and renin mRNA levels after 2 h. IGF-I, at a dosage that stimulated kallikrein mRNA levels in control rats, had no effect on renal kallikrein and renin content or mRNA levels in diabetic rats. However, infusion of a fivefold higher IGF-I dosage resulted in a two- to threefold increase in kallikrein and renin mRNA levels in 2 h. These data suggest that 1) diabetes suppresses kallikrein and renin gene expression, and these abnormalities are reversed by insulin or IGF-I; and 2) the diabetic state produces resistance to IGF-I induction of kallikrein and renin gene expression. These changes in regulated synthesis of kallikrein and renin in the kidney may underlie renal vascular changes that develop in diabetes.
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PMID:Induction of renal kallikrein and renin gene expression by insulin and IGF-I in the diabetic rat. 939 95

Approximately 30% of patients with type 1 and type 2 diabetes develop diabetic nephropathy. Apart from metabolic control, genetic predisposition plays an important role in its genesis. Analysis of intermediate phenotypic markers showed that the activity of Na/Li- and Na+/H(+)-countertransport is increased in patients with diabetic nephropathy. The renin-angiotensin system is of crucial importance as a system for therapeutic intervention and as genetic marker for susceptibility to renal disease. Consequently, the analysis of molecular genetic markers has focused on a polymorphism in the gene for the angiotensin II converting enzyme (ACE). However, the analysis of the I/D-polymorphism with respect to development of diabetic nephropathy in type 1 and type 2 diabetes has yielded conflicting results, at least in type 1 diabetes. These discrepant results may be due to differences in definition, sample size and ethnic background of the patients. In IgA glomerulonephritis it has been shown that the DD genotype (which is correlated with higher serum and tissue ACE activity compared to II genotype) is associated with a more rapid deterioration of renal function. The same adverse effect of the DD genotype could also be demonstrated in patients with diabetic nephropathy. Two studies examined the response to treatment according to the different genotypes, with contradictory results. A Japanese study showed a more pronounced reduction in proteinuria under ACE inhibitor treatment in patients with DD genotype, whereas a Danish study showed that patients with the DD genotype exhibited a steeper decline in renal function despite ACE inhibitor treatment. The data available for other candidate genes are fragmentary and negative throughout.
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PMID:Genetic determinants of diabetic renal disease and their impact on therapeutic interventions. 940 16

Classically, the renin-angiotensin system (RAS) in diabetes was thought to be suppressed, and relatively unimportant in the regulation of hemodynamics and the development of complications. However, studies of pharmacologic interruption of the RAS with angiotensin converting enzyme (ACE) inhibition have implicated the RAS in the progression of diabetic nephropathy. Preliminary evidence also suggests a beneficial effect of angiotensin II receptor antagonists. The relative roles of the systemic versus intrarenal RAS in this process are under active investigation. Though plasma renin is generally low, there may be subtle changes in angiotensin (Ang) II metabolism that sustain relatively higher plasma Ang II levels. Furthermore, the intrarenal RAS may not be suppressed. Renal renin levels tend to be disproportionately elevated, as compared to plasma values. Renal Ang II levels are normal, and renal mRNAs for RAS components have been variable. In general, lack of intrarenal RAS suppression (despite plasma volume and increased exchangeable sodium) may indicate inappropriate activity of the local tissue RAS, and act as a proximate cause of the systemic RAS suppression. Ang II-mediated injury may occur via stimulation of sclerosing mediators, and there is evidence that hyperglycemia acts synergistically with Ang II to promote cellular injury. Together, these recent investigations lend further support to the notion that the RAS plays an important role in diabetic nephropathy, and are helping to shed light on the mechanisms of progressive renal injury.
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PMID:Role of local and systemic angiotensin in diabetic renal disease. 940 35

Diabetic nephropathy is the most common cause of end-stage renal disease (ESRD) in the United States, and accounts for 35% of all the patients with ESRD entering a dialysis program; 63% of patients with diabetic nephropathy have type II diabetes mellitus. Hypertension is a major risk factor for renal disease and is common in people with diabetes mellitus. Strategies for preventing the progression of renal failure in patients with diabetes mellitus include glycemic control, and control of blood pressure. Blocking the renin-angiotensin system (RAS) slows the progression of established diabetic nephropathy in type I diabetes mellitus, and inhibiting angiotensin II formation retards or impedes the progression from microalbuminuria to established diabetic nephropathy (macroproteinuria) in people with type I diabetes mellitus. The situation could be the same for people with type II diabetes mellitus. The ability of RAS blockade using irbesartan, an AT1 angiotensin II receptor antagonist, to slow the progression in renal failure has been compared with that of the calcium channel blocker amlodipine and placebo in a pilot study. The results suggest that blockade of the RAS, in this case with irbesartan, is at least equivalent to calcium channel blockers with respect to antihypertensive efficacy, but provides better renoprotective benefits.
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PMID:Renoprotection and renin-angiotensin system blockade in diabetes mellitus. 943 77

Overproduction of transforming growth factor-beta clearly underlies tissue fibrosis in numerous experimental and human diseases. Transforming growth factor-beta's powerful fibrogenic action results from simultaneous stimulation of matrix protein synthesis, inhibition of matrix degradation, and enhanced integrin expression that facilitates matrix assembly. In animals, overexpression of transforming growth factor-beta by intravenous injection, transient gene transfer, or transgene insertion has shown that the kidney is highly susceptible to rapid fibrosis. The same seems true in human disease, where excessive transforming growth factor-beta has been demonstrated in glomerulonephritis, diabetic nephropathy, and hypertensive glomerular injury. A possible explanation for the kidney's particular susceptibility to fibrosis may be the recent discovery of biologically complex interactions between the renin-angiotensin system and transforming growth factor-beta. Alterations in glomerular hemodynamics can activate both the renin-angiotensin system and transforming growth factor-beta. Components of the renin-angiotensin system act to further stimulate production of transforming growth factor-beta and plasminogen activator inhibitor leading to rapid matrix accumulation. In volume depletion, transforming growth factor-beta is released from juxtaglomerular cells and may act synergistically with angiotensin II to accentuate vasoconstriction and acute renal failure. Interaction of the renin-angiotensin system and transforming growth factor-beta has important clinical implications. The protective effect of inhibition of the renin-angiotensin system in experimental and human kidney diseases correlates closely with the suppression of transforming growth factor-beta production. This suggests that transforming growth factor-beta, in addition to blood pressure, should be a therapeutic target. Higher doses or different combinations of drugs that block the renin-angiotensin system or entirely new drug strategies may be needed to achieve a greater antifibrotic effect.
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PMID:Interactions of transforming growth factor-beta and angiotensin II in renal fibrosis. 945

A role of renal angiotensin-converting enzyme (ACE) in diabetic nephropathy has been suggested. Immunohistochemical localization of ACE was studied in 20 non-insulin-dependent diabetes mellitus patients with diabetic nephropathy and 17 healthy kidney transplant donors, with ACE gene insertion/deletion (I/D) polymorphism also examined in the latter. Immunohistochemical studies indicated that ACE staining was significantly (P < 0.01) enhanced in glomeruli and slightly decreased in proximal tubules in diabetic patients. Glomeruli positive for ACE immunostaining were observed in 23.5% of the healthy subjects and in 80% of the diabetic patients. All patients with nodular lesions had ACE-positive glomeruli and showed significantly (P < 0.01) more intense glomerular ACE immunostaining than patients without nodular lesions. Among healthy controls, subjects with the DD genotype had ACE-positive glomeruli more frequently and tended to show slightly increased intensity on proximal tubule ACE immunostaining compared with subjects with other genotypes. These observations suggest that increased ACE localization in glomeruli is likely to be one of the factors in the increased renin-angiotensin system activity in glomeruli in patients with diabetic nephropathy. There is a possibility that ACE gene I/D polymorphism may be related to renal ACE immunohistochemical localization.
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PMID:Renal ACE immunohistochemical localization in NIDDM patients with nephropathy. 946 1

Nephropathy is a frequent complication of long term diabetes. Diabetic nephropathy is the major determinant of premature morbidity and mortality both in insulin-dependent (IDDM) and in non-insulin dependent-diabetes mellitus (NIDDM). There is good evidence that genetic predisposition plays a major role in development of diabetic nephropathy. This hypothesis is based on the observation that diabetic nephropathy clusters within families, both in IDDM and NIDDM. Components of the renin-angiotensin system (RAS) are plausible candidate genes to examine for a association with microalbuminuria and diabetic nephropathy. In this study we compared the distribution of PstI melting polymorphism at the ACE locus among NIDDM patients with diabetic nephropathy and in patients who, despite long duration of NIDDM, remain without this complication. The 220 NIDDM patients for whom DNA was available were classified into two groups according to their renal status: normoalbuminuric control subjects (n = 80) who are NIDDM patients with an A/C ratio < 2.5 and nephropathy cases (n = 140) who are NIDDM patients with A/C ratio > 2.5. Albumin excretion rate was assayed by radioimmunoassay. HbA1c was assayed using HPLC methods, creatinine--using Jaffe methods and DNA analysis using PCR reaction, and then after the amplification product was digested with PstI enzyme. The study revealed that PstI sequence differences ("+/= and -") in the ACE gene do not contribute to genetic susceptibility to diabetic nephropathy in NIDDM.
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PMID:[Is PstI polymorphism of the angiotensin I converting enzyme gene associated with nephropathy development in non-insulin-dependent diabetes mellitus (preliminary study)]. 949 4


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