Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0730345 (microalbuminuria)
 4,018 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A 2-year randomized placebo-controlled double-blind trial of 250 mg day-1 of the aldose reductase inhibitor Sorbinil in severe symptomatic chronic peripheral neuropathy was performed in 21 diabetic patients. Due to adverse reactions 8 patients completed the trial on Sorbinil and 6 patients on placebo. Despite differences in baseline neurophysiological parameters, duration of diabetes, and presence of retinopathy between the placebo and treatment groups, there were no initial differences in in vitro platelet aggregation, albumin excretion rate (AER) or muscle capillary basement membrane thickness. After 2 years the median deterioration in AER in the placebo group was 18.4 micrograms min-1 (range 2.6-64.8 micrograms min-1). This deterioration was significant (p less than 0.03). The change in AER in the Sorbinil group was +1.25 (-10.7 to +20.4) micrograms min-1, an insignificant change. In vitro platelet responsiveness to collagen and adenosine diphosphate (ADP) increased in the placebo group (median change max% collagen + 8 (+2 to +30)%; ADP +4.5 (0 to +20)% compared with a fall in the Sorbinil treated patients (median change; collagen -17.5 (-2 to -40)%, p less than 0.05; ADP, -4 (0 to -25)%, p less than 0.05). Muscle capillary basement membrane thickness was measured in only 3 patients in each group and did not alter significantly during the trial. All 12 neurophysiological measurements showed no significant changes between the treatment and placebo groups. The data suggest that aldose reductase inhibition has effects on platelet reactivity and microalbuminuria.
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PMID:Prolonged aldose reductase inhibition in chronic peripheral diabetic neuropathy: effects on microangiopathy. 213 66

Fig. 5 provides a summary of the natural history of diabetic nephropathy in IDDM patients. The figure also includes the possibilities of intervention in the various stages of diabetic nephropathy. GFR values in normals are shown by the hatched area in the upper part of the figure. The lower part shows development of albuminuria. The level 20-200 micrograms/min is the microalbuminuric range. At present it is not possible to predict a malignant course either from the parental history (1), or from the prediabetic course (2). Neither at clinical diagnosis of diabetes, can complications be predicted (3). The figure shows a typical course in a patient developing diabetes at the age of 14 years. The patient showed poor metabolic control as indicated by the high level of GFR (greater than 150 ml/min) (4) and the increasing albumin excretion rate (4). At the age of 22 years the patient developed microalbuminuria (5) and later clinical nephropathy at age 30 years, typically after 16 years of diabetes. Blood pressure rises, and GFR starts to decline during incipient diabetic nephropathy with increasing microalbuminuria (greater than 70 micrograms/min) (5) (6), and end-stage renal failure reached at the age of 40 years,--if intervention is not undertaken. Intervention is possible as follows: A) hyperfiltration may be reduced by non-glycemic intervention such as a moderate reduction of protein intake, treatment with aldose reductase inhibitors (work in progress) or acute administration of a somatostatin analogue.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:The effect of blood pressure intervention on renal function in insulin-dependent diabetes. 261 18

In previous studies in the Sprague-Dawley rat, Williams and coworkers reported the phenomenon of selective urinary excretion of glucosylated albumin (editing, i.e., the percent glucosylation of urinary albumin is more than that of plasma albumin) by the mammalian kidney. Ghiggeri and coworkers subsequently found that the extent of editing is reduced in human diabetics. Moreover, the reduction in editing in diabetes correlates inversely with levels of microalbuminuria. We also find reduction in the extent of editing in diabetic humans. We find a striking inverse correlation not only with the magnitude of microalbuminuria but also with the extent of plasma albumin glucosylation. In contrast, we found little correlation between the reduction in editing and the duration of diabetes in human subjects. Stz induced diabetes in the Sprague-Dawley rat is associated with a striking and rapid reduction in editing which develops virtually with the same kinetics exhibited by the appearance of hyperglycemia. This loss of editing is rapidly reversed by daily administration of insulin but not by aldose reductase inhibitors. Mannitol infusion in anesthetized Wistar rats resulted in an increase in urine volume, GFR, and microalbuminuria, and was also accompanied by a marked reduction in editing. This reduction was rapidly reversed by a cessation of mannitol infusion. We propose here that glucosylated albumin (in contrast to unmodified albumin) is not reabsorbed by the proximal tubule, and thus, is preferentially excreted in the urine. We postulate that the increase in GFR which emerges as a consequence of increased plasma osmolality in diabetes mellitus delivers more albumin to the proximal tubule than can be reabsorbed. This results in a dilution of excreted glucosylated albumin molecules by excreted unmodified albumin, which appears as the early microscopic albuminuria of diabetes. Paradoxically, the fall in apparent editing is accompanied by an absolute increase in the total quantity of glucosylated albumin excreted. In contrast, we found that editing of glucosylated albumin by the normal kidney is found to gradually decline as a function of age without the appearance of microalbuminuria. This suggests that a different mechanism operates to produce the loss of editing seen with aging in man, and as clearly (but in a shorter absolute time intervals) in the Fischer-344 rat.
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PMID:Suggested mechanism for the selective excretion of glucosylated albumin. The effects of diabetes mellitus and aging on this process and the origins of diabetic microalbuminuria. 311 57

Diabetic nephropathy is the single most common cause of end-stage renal disease in the United States. Recently, several major therapeutic interventions have been developed and demonstrated to slow or halt the progression of renal failure in patients with diabetes and diabetic kidney disease. The Diabetes Control and Complications Trial demonstrated that microalbuminuria developed in fewer patients in the intensive blood sugar control group than in the conventional therapy group. Similarly, the risk of developing proteinuria was reduced by intensive blood sugar control. Multiple studies have demonstrated that in patients with insulin-dependent diabetes and proteinuria, lowering the systemic blood pressure slows the rate of decline in renal function and improves patients' survival. In the recently completed trial of ACE inhibition in diabetic nephropathy, ACE inhibitors were specifically shown to decrease dramatically the risk of doubling of serum creatinine or reaching a combined outcome of end-stage renal disease or death. In studies in small numbers of patients with insulin-dependent diabetes and established diabetic nephropathy, dietary protein restriction has also been demonstrated to slow the rate of decline of renal function. New potential interventions currently undergoing study include the use of aldose reductase inhibitors, the use of drugs that prevent the formation of advanced glycosylation end-products, and the use of angiotensin II receptor antagonists. Thus, several established benefits have recently been demonstrated to help prevent the development of or slow the progression of diabetic nephropathy, including blood pressure control, blood sugar control, and treatment with ACE inhibitors. Dietary protein restriction may also be of benefit. Multiple new interventions are undergoing clinical trials currently.
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PMID:Medical management of nephropathy in type I diabetes mellitus: current recommendations. 874 76

The dinucleotide repeat polymorphism (5'-ALR2) in the promoter region of the aldose reductase gene on chromosome 7q35 has been implicated in the development of diabetic nephropathy in Type I (insulin-dependent) diabetes mellitus, and markers flanking the aldose reductase locus have given evidence suggestive of a linkage between diabetic nephropathy and Type II (non-insulin-dependent) diabetes mellitus in Pima Indians. To examine whether the 5'-ALR2 polymorphism in the aldose reductase gene is involved in the development of diabetic nephropathy in Caucasians with Type II diabetes, we carried out a large association study. Patients with Type II diabetes from one outpatient clinic were screened for diabetic nephropathy and divided into three groups according to the degree of this disease: 179 patients with normoalbuminuria, 225 patients with microalbuminuria and 70 patients with proteinuria. Patients with normoalbuminuria were included in the study only if they had had Type II diabetes for 10 or more years. DNA from all patients was genotyped for the 5'-ALR2 polymorphism using a previously established polymerase chain reaction protocol. The frequency of the putative risk allele Z-2 was 34.6%, 34.2% and 33.6% in the normoalbuminuria, microalbuminuria and proteinuria groups, respectively. Similarly no difference among groups was found for the frequency of the putative protective allele Z + 2. In conclusion, the results of our association study in Caucasian patients with Type II diabetes do not support the hypothesis that the 5'-ALR2 polymorphism in the aldose reductase gene contributes to susceptibility to diabetic nephropathy.
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PMID:The role of aldose reductase gene in the susceptibility to diabetic nephropathy in Type II (non-insulin-dependent) diabetes mellitus. 1002 85

Diabetes mellitus causes profound alterations in many body tissues. Microvascular diabetic complications include diabetic neuropathy, nephropathy and retinopathy. Nephropathy first becomes manifest with hyperfiltration and microalbuminuria. These functional changes evolve over several years to a stage of marked deterioration of renal function. The possible preventive measures are metabolic control, reduction of dietary protein intake and use of ACE-inhibitors. Metabolic control is also important for the prevention of diabetic retinopathy. In fact, patients with HbA1c higher than 10% have an increased risk of progression of retinopathy. Moreover, an accelerated progression of retinopathy has been observed in patients with systemic hypertension following the onset of microalbuminuria. It has been demonstrated that diabetic neuropathy can also be present during childhood; therefore, it is possible to detect electrophysiological abnormalities in children and adolescents with IDDM. Glycaemic and blood pressure control are, so far, the main means for possible prevention or modification of the natural history of diabetic microvascular complications. Tight glycaemic control may have beneficial effects for diabetic neuropathy. In addition, other preventive measures, such as aldose reductase inhibitors, gangliosides, neurotrophic vitamins, etc., have been studied in the last years. However, no conclusive results have been obtained so far.
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PMID:Prevention of microvascular complications in diabetic children and adolescents. 1019 52

Diabetic Nephropathy (DN) is the commonest cause of end-stage renal failure (ESRF) in the Western world. Diabetic nephropathy follows a well outline clinical course, starting with microalbuminuria through proteinuria, azotaemia and culminating in ESRF. Before the onset of overt proteinuria, there are various renal functional changes including renal hyperfiltration, hyperperfusion, and increasing capillary permeability to macromolecules. Basement-membrane thickening and mesangial expansion have long been recognized as pathological hallmark of diabetes. It has been postulated that DN occurs as a result of the interplay of metabolic and hemodynamic factors in the renal microcirculation. There is no doubt that there is a positive relationship between hyperglycaemia, which is necessary but not sufficient, and microvascular complications. The accumulation of advanced glycosylated end-products (AGEs), the activation of isoform(s) of protein kinase C (PKC) and the acceleration of the aldose reductase pathway may explain how hyperglycemia damages tissue. PKC is one of the key signaling molecules in the induction of the vascular pathology of diabetes. The balance between extracellular matrix production and degradation is important in this context. Transforming growth factor-beta (TGF-beta) appears to play a pivotal role in accumulation in the diabetic kidney. Hemodynamic disturbances are believed to be directly responsible for the development of glomerulosclerosis and its attendant proteinuria. There is familial clustering of diabetic kidney disease. A number of gene loci have been investigated to try to explain the genetic susceptibility to diabetic nephropathy. The genes coding for components of renin-angiotensin system have drawn special attention, due to the central role that this system plays in the regulation of blood pressure, sodium metabolism, and renal hemodynamics. Endothelial dysfunction is closely associated with the development of diabetic retinopathy, nephropathy and atherosclerosis, both in IDDM and in NIDDM. The pathogenesis of diabetic nephropathy is not clarified completely yet.
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PMID:Pathogenesis of diabetic nephropathy. 1146 May 89

The aim of the present study was to elucidate the long-term effect of epalrestat, an aldose reductase inhibitor (ARI), on renal function in patients with type 2 diabetes mellitus showing microalbuminuria. Patients were allocated to two groups (cases and controls) matched for age, BMI, and the extent of urinary albumin excretion (UAE). Thirty-five type 2 diabetic patients presenting microalbuminuria were included in this study: cases were treated with epalrestat (150 mg/day) for 5 years. No significant changes were found in blood pressure, HbA1c, and total cholesterol in either group during the observation period. In the control group, UAE increased significantly (P<.01) from 82+/-12 mg/g Cr at the baseline to 301+/-111 mg/g Cr at the end of the study, while UAE remained unchanged, 81+/-15 mg/g Cr at the baseline and 87+/-19 mg/g Cr at the end of the study, in the epalrestat-treated group. Reciprocal creatinine measured by an enzyme assay decreased significantly (P<.01) in both groups; however, the reduction rate in the epalrestat-treated group was significantly (P<.05) smaller than that in the control group. These results suggest the potential usefulness of ARIs in preventing the progression of incipient diabetic nephropathy in patients with type 2 diabetes mellitus.
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PMID:Long-term effect of epalrestat, an aldose reductase inhibitor, on the development of incipient diabetic nephropathy in Type 2 diabetic patients. 1152 97

Diabetic nephropathy (DN) has become the leading cause of end stage failure, but no renoprotective treatment has been very available for use in DN. Astragalus saponin I (AS I), a component extracted from Astragalus membranaceus BUNGE, was studied in experimental DN induced by administration of streptozotocin in male rats. The early DN rats were treated with 3 doses of AS I for 8 weeks to analyze its efficacy with different parameters. By comparison with vehicle-treated DN rats, the renal hypertrophy, the oxidative stress intensity, and the blood glucose level of DN rats were ameliorated by AS I. Also, the microalbuminuria level, advanced glycated end-products either in serum or in kidney cortex, and the aldose reductase activity were significantly reduced. Furthermore, the expression of transforming growth factor beta1 mRNA in kidney cortex by RT-PCR analysis was markedly declined. Both the relative grade of mesangium hyperplasia by microscopical observation and the thickness of glomerular base membrane by electron microscope measurement were decreased significantly. Therefore, the results suggest that AS I has therapeutic effects on several pharmacological targets in the progress of DN and is a potential drug for prevention of early stage DN.
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PMID:Protective effects of Astragalus saponin I on early stage of diabetic nephropathy in rats. 1521 51

Diabetes is currently one of the leading causes of end-stage renal failure requiring renal replacement therapy in the Western World. About 15% to 20% of type 1 diabetic patients and 30% to 40% of type 2 diabetic patients will eventually develop end-stage renal failure. To prevent the development or progression of diabetic kidney disease, good glycaemic control remains the cornerstone in the management of diabetic patients. Beyond glycaemic control, other metabolic factors have been shown to be involved in the development of diabetic kidney disease, i.e. advanced glycation endproducts (AGEs) and the aldose reductase pathway. Furthermore, an adequate control of high blood pressure and treatment of microalbuminuria are major therapeutic targes. To achieve adequate blood pressure control, a combination therapy with different classes of antihypertensive agents is often necessary, especially including angiotensin-converting enzyme inhibitors and angiotensin receptor blockers. Other vasoactive factors involved in diabetic nephropathy such as endothelin and nitric oxide will be covered briefly. Besides hyperglycaemia and high blood pressure, other risk factors have been identified in the development or progression of diabetic kidney disease: smoking, hyperlipidaemia, obesity and high protein intake. Their impact on renal function will be highlighted. Finally, recent research has also identified intracellular pathways such as the diacylglycerol-protein kinase C pathway and several growth factors, such as growth hormone, insulin-like growth factor, transforming growth factor-beta, vascular endothelial growth factor, and platelet derived growth factor as players in diabetic kidney disease.
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PMID:Novel insights in the treatment of diabetic nephropathy. 1822 60


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