Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011849 (diabetes)
 277,896 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Increasing number of diabetic patients develop different stages of renal failure. However, often an inappropriate parameter, the serum creatinine is measured as a marker of glomerular function. Calculated glomerular filtration rate or endogenous creatinine clearance are suggested to be used for the estimation of the glomerular function. Important structures preventing proteinuria in the kidney are glomerular basement membrane, podocytes and proximal tubular cells. In diabetes mellitus loss of nephrin of podocytes can play a role in the development of microalbuminuria, and podocyte desquamation may result in the progression to proteinuria. In diabetes mellitus there is an increased formation of advanced glycation endproducts (AGE), of which the only elimination organ is the kidney. The AGE induce proteinuria and atherosclerosis. Therefore, in diabetes mellitus a vicious circle develops due to proteinuria, nephron loss and accumulation of AGE, which play a role in the initiation and progression of diabetic nephropathy and atherosclerosis. Angiotensin converting enzyme inhibitors and angiotensin receptor blockers having antiproteinuric effect may decrease the risk of diabetic nephropathy and atherosclerosis. Improvement of carbohydrate metabolism with a consequential decrease in the formation of AGE is an important contributor to the prevention and treatment of diabetic nephropathy and atherosclerosis.
Diabetes Res Clin Pract 2005 Jun
PMID:Prevention and treatment of diabetic nephropathy. 1595 73

Diabetic nephropathy is one of the major microvascular complications in diabetes and is the leading cause of end-stage renal disease worldwide. Among various factors, angiogenesis-associated factors such as vascular endothelial growth factor (VEGF)-A and angiopoietin (Ang)-2 are involved in the development of diabetic nephropathy. We previously reported the therapeutic efficacy of antiangiogenic tumstatin peptide in the early diabetic nephropathy model. Here, we examine the effect of endostatin peptide, a potent inhibitor of angiogenesis derived from type XVIII collagen, in preventing progression in the type 1 diabetic nephropathy mouse model. Endostatin peptide did not affect hyperglycemia induced by streptozotocin (STZ). Glomerular hypertrophy, hyperfiltration, and albuminuria were significantly suppressed by endostatin peptide (5 mg/kg) in STZ-induced diabetic mice. Glomerular mesangial matrix expansion, the increase of glomerular type IV collagen, endothelial area (CD31(+)), and F4/80(+) monocyte/macrophage accumulation were significantly inhibited by endostatin peptide. Increase in the renal expression of VEGF-A, flk-1, Ang-2, an antagonist of angiopoietin-1, transforming growth factor-beta1, interleukin-6, and monocyte chemoattractant protein-1 was inhibited by endostatin peptide in diabetic mice. Decrease of nephrin mRNA and protein in diabetic mice was suppressed by treatment with endostatin peptide. The level of endostatin in the renal cortex and sera was increased in diabetic mice. Endogenous renal levels of endostatin were decreased in endostatin peptide-treated groups in parallel with VEGF-A. Although serum levels of endostatin were decreased in the low-dose endostatin-peptide group, high-dose administration resulted in elevated serum levels of endostatin. These results demonstrate the potential use of antiangiogenic endostatin peptide as a novel therapeutic agent in diabetic nephropathy.
Diabetes 2005 Oct
PMID:Antiangiogenic endostatin peptide ameliorates renal alterations in the early stage of a type 1 diabetic nephropathy model. 1618 90

We previously demonstrated the anti-inflammatory effects and renal tissue protection in response to adenosine A(2A)-receptor (A(2A)R) activation in acute renal injury. We sought to extend these studies and determine the efficacy of A(2A)R agonists in a chronic model of renal injury. We hypothesized that A(2A) agonists mediate renal tissue protection in diabetic nephropathy by reducing glomerular inflammation. Diabetes was induced with single intravenous injection of streptozotocin in Sprague-Dawley rats (50 mg/kg). Increases in urinary albumin excretion (UAE) and plasma creatinine at week 6 in the diabetes group (26- and 6-fold over control, respectively) were markedly reduced by continuous subcutaneous administration of ATL146e (10 ng x kg(-1) x min(-1)), a selective A(2A) agonist. The increase in UAE in the diabetes group was associated with a significant reduction in the expression of slit diaphragm-associated molecules compared with control (nephrin; P < 0.05 and podocin; P < 0.005) that was reversed by ATL146e treatment. Diabetes led to an increase in urinary excretion of monocyte chemoattractant protein-1 (705% of control), TNF-alpha (1,586% of control), IFN-gamma (298% of control), kidney fibronectin mRNA (457% of control), and glomerular infiltration of macrophages (764% of control), effects significantly reduced by ATL146e treatment. Mesangial expansion and basement membrane thickness were reduced with ATL146e. To further confirm the selectivity of ATL146e, we used wild-type (WT) or A(2A)knockout (A(2A)-KO) mice. Four weeks after diabetes, UAE increased significantly in both WT and A(2A)-KO diabetic mice (3.0- and 3.3-fold over control). A(2A) agonist treatment blocked the increase in UAE in WT diabetic mice (P < 0.001), whereas it had no effect on the A(2A)-KO diabetic mice. These results demonstrate that chronic A(2A)R activation in diabetic rats 1) ameliorates histological and functional changes in kidneys induced by diabetes and 2) causes reduced inflammation associated with diabetic nephropathy.
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PMID:Adenosine A2A receptor activation attenuates inflammation and injury in diabetic nephropathy. 1633 31

One of the mechanisms involved in the progression of diabetic nephropathy, the most common cause of end-stage renal failure, is angiogenic phenomenon associated with the increase of angiogenic factors such as vascular endothelial growth factor (VEGF)-A and angiopoietin (Ang)-2, an antagonist of Ang-1. In the present study, we examined the therapeutic efficacy of 2-(8-hydroxy-6-methoxy-1-oxo-1H-2-benzopyran-3-yl) propionic acid (NM-3), a small molecule isocoumarin with antiangiogenic activity, using diabetic db/db mice, a model of obese type 2 diabetes. Increases in kidney weight, glomerular volume, creatinine clearance, urinary albumin excretion, total mesangial fraction, glomerular type IV collagen, glomerular endothelial area (CD31(+)), and monocyte/macrophage accumulation (F4/80(+)) observed in control db/db mice were significantly suppressed by daily intraperitoneal injection of NM-3 (100 mg/kg, for 8 weeks). Increases in renal expression of VEGF-A, Ang-2, fibrogenic factor transforming growth factor (TGF)-beta1, and chemokine monocyte chemoattractant protein-1 but not tumor necrosis factor-alpha were also inhibited by NM-3 in db/db mice. Furthermore, decreases of nephrin mRNA and protein levels in db/db mice were recovered by NM-3. In addition, treatment of db/db mice with NM-3 did not affect body weight, blood glucose, serum insulin, or food consumption. NM-3 significantly suppressed the increase of VEGF induced by high glucose in cultured podocytes and also suppressed the increase of VEGF and TGF-beta induced by high glucose in cultured mesangial cells. Taken together, these results demonstrate the potential use of NM-3 as a novel therapeutic agent for renal alterations in type 2 diabetes.
Diabetes 2006 May
PMID:2-(8-hydroxy-6-methoxy-1-oxo-1h-2-benzopyran-3-yl) propionic acid, an inhibitor of angiogenesis, ameliorates renal alterations in obese type 2 diabetic mice. 1664 77

Longstanding diabetes causes renal injury with early dropout of podocytes, albuminuria, glomerular and tubulointerstitial fibrosis, and progressive renal failure. The renal pathology seems to be driven, in part, by TGF-beta and is associated with a loss of renal bone morphogenic protein-7 (BMP-7) expression. Here, the hypothesis that maintenance of renal (especially podocyte) BMP-7 by transgenic expression reduces diabetic renal injury was tested. Diabetic mice that expressed the phosphoenolpyruvate carboxykinase promoter-driven BMP-7 transgene and nondiabetic, transgenic mice as well as diabetic and nondiabetic wild-type controls were studied for up to 1 yr. Transgenic expression of BMP-7 in glomerular podocytes and proximal tubules prevents podocyte dropout and reductions in nephrin levels in diabetic mice. Maintenance of BMP-7 also reduces glomerular fibrosis and interstitial collagen accumulation as well as collagen I and fibronectin expression. Diabetic wild-type mice develop progressive albuminuria, which is substantially reduced in transgenic mice. These effects of the BMP-7 transgene occur without changing renal TGF-beta levels. It is concluded that maintenance of renal BMP-7 during the evolution of diabetic nephropathy reduces diabetic renal injury, especially podocyte dropout. The findings also establish a role for endogenous glomerular BMP-7 as an autocrine regulator of podocyte integrity in vivo.
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PMID:Renal bone morphogenetic protein-7 protects against diabetic nephropathy. 1689 16

For investigation of how the vascular endothelial growth factor (VEGF) system participates in the pathogenesis of diabetic kidney disease, type 2 diabetic db/db and control db/m mice were treated intraperitoneally with vehicle or 2 mg/kg of a pan-VEGF receptor tyrosine kinase inhibitor, SU5416, twice a week for 8 wk. Efficacy of SU5416 treatment in the kidney was verified by the inhibition of VEGF receptor-1 phosphorylation. Glomerular VEGF immunostaining, normally increased in diabetes, was unaffected by SU5416. Plasma creatinine did not change with diabetes or SU5416 treatment. The primary end point of albuminuria increased approximately four-fold in the diabetic db/db mice but was significantly ameliorated by SU5416. Correlates of albuminuria were investigated. Diabetic glomerular basement membrane thickening was prevented in the SU5416-treated db/db mice, whereas mesangial matrix expansion remained unchanged by treatment. The density of open slit pores between podocyte foot processes was decreased in db/db diabetes but was partly increased toward normal by SU5416. Finally, nephrin protein by immunofluorescence was decreased in the db/db mice but was significantly restored by SU5416. Paradoxically, total nephrin protein by immunoblotting was increased in diabetes, pointing toward a possible dysregulation of nephrin trafficking. Diabetic albuminuria is partially a function of VEGF receptor signaling overactivity. VEGF signaling was found to affect a number of podocyte-driven manifestations such as GBM thickening, slit pore density, and nephrin quantity, all of which are associated with the extent of diabetic albuminuria. By impeding these pathophysiologic processes, VEGF receptor inhibition by SU5416 might become a useful adjunct to anti-albuminuria therapy in diabetic nephropathy.
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PMID:Blockade of vascular endothelial growth factor signaling ameliorates diabetic albuminuria in mice. 1698 63

Metabolic syndrome is an important risk factor for proteinuria and chronic kidney disease independent of diabetes and hypertension; however, the underlying mechanisms have not been elucidated. Aldosterone is implicated in target organ injury of obesity-related disorders. This study investigated the role of aldosterone in the early nephropathy of 17-wk-old SHR/NDmcr-cp, a rat model of metabolic syndrome. Proteinuria was prominent in SHR/NDmcr-cp compared with nonobese SHR, which was accompanied by podocyte injury as evidenced by foot process effacement, induction of desmin and attenuation of nephrin. Serum aldosterone level, renal and glomerular expressions of aldosterone effector kinase Sgk1, and oxidative stress markers all were elevated in SHR/NDmcr-cp. Mineralocorticoid receptors were expressed in glomerular podocytes. Eplerenone, a selective aldosterone blocker, effectively improved podocyte damage, proteinuria, Sgk1, and oxidant stress. An antioxidant tempol also alleviated podocyte impairment and proteinuria, along with inhibition of Sgk1. As for the mechanisms of aldosterone excess, visceral adipocytes that were isolated from SHR/NDmcr-cp secreted substances that stimulate aldosterone production in adrenocortical cells. The aldosterone-releasing activity of adipocytes was not inhibited by candesartan. Adipocytes from nonobese SHR did not show such activity. In conclusion, SHR/NDmcr-cp exhibit enhanced aldosterone signaling, podocyte injury, and proteinuria, which are ameliorated by eplerenone or tempol. The data also suggest that adipocyte-derived factors other than angiotensin II might contribute to the aldosterone excess of this model.
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PMID:Enhanced aldosterone signaling in the early nephropathy of rats with metabolic syndrome: possible contribution of fat-derived factors. 1708 36

Diabetes mellitus is a major health problem across the world. Diabetic retinopathy (DR) and nephropathy are two of the major complications of diabetes. DR is the leading cause of blindness and diabetic nephropathy is the leading cause of end-stage renal failure. We have examined the potential value of circulating nucleic acids in the detection and monitoring of these two complications of diabetes. mRNA for nephrin was significantly higher in all diabetics compared to healthy controls and it was significantly higher in normoalbuminuric patients compared to healthy controls. This may indicate progression to microalbuminuric stage. Circulating rhodopsin mRNA was detectable in healthy subjects and in diabetic patients. It was significantly raised in diabetic patients with retinopathy. Higher rhodopsin mRNA in diabetic patients without retinopathy suggests that some of them may go on to develop it or already have it subclinically. Circulating nucleic acids have the potential to be noninvasive molecular tests for diabetic complications.
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PMID:Circulating nucleic acids and diabetic complications. 1710 19

The protein kinase C (PKC)-beta isoform has been implicated to play a pivotal role in the development of diabetic kidney disease. We tested this hypothesis by inducing diabetic nephropathy in PKC-beta-deficient (PKC-beta(-/-)) mice. We studied nondiabetic and streptozotocin-induced diabetic PKC-beta(-/-) mice compared with appropriate 129/SV wild-type mice. After 8 weeks of diabetes, the high-glucose-induced renal and glomerular hypertrophy, as well as the increased expression of extracellular matrix proteins such as collagen and fibronectin, was reduced in PKC-beta(-/-) mice. Furthermore, the high-glucose-induced expression of the profibrotic cytokine transforming growth factor (TGF)-beta1 and connective tissue growth factor were significantly diminished in the diabetic PKC-beta(-/-) mice compared with diabetic wild-type mice, suggesting a role of the PKC-beta isoform in the regulation of renal hypertrophy. Notably, increased urinary albumin-to-creatinine ratio persisted in the diabetic PKC-beta(-/-) mice. The loss of the basement membrane proteoglycan perlecan and the podocyte protein nephrin in the diabetic state was not prevented in the PKC-beta(-/-) mice as previously demonstrated in the nonalbuminuric diabetic PKC-alpha(-/-) mice. In summary, the differential effects of PKC-beta deficiency on diabetes-induced renal hypertrophy and albuminuria suggest that PKC-beta contributes to high-glucose-induced TGF-beta1 expression and renal fibrosis, whereas perlecan, as well as nephrin, expression and albuminuria is regulated by other signaling pathways.
Diabetes 2007 Feb
PMID:Deletion of protein kinase C-beta isoform in vivo reduces renal hypertrophy but not albuminuria in the streptozotocin-induced diabetic mouse model. 1725 78

The leading causes of albuminuria and end-stage renal failure are secondary to abnormalities in the production or cellular action of insulin, including diabetes and hyperinsulinemic metabolic syndrome. The human glomerular podocyte is a critical cell for maintaining the filtration barrier of the kidney and preventing albuminuria. We have recently shown this cell to be insulin sensitive with respect to glucose uptake, with kinetics similar to muscle cells. We now show that the podocyte protein nephrin is essential for this process. Conditionally immortalized podocytes from two different patients with nephrin mutations (natural human nephrin mutant models) were unresponsive to insulin. Knocking nephrin down with siRNA in wild-type podocytes abrogated the insulin response, and stable nephrin transfection of nephrin-deficient podocytes rescued their insulin response. Mechanistically, we show that nephrin allows the GLUT1- and GLUT4-rich vesicles to fuse with the membrane of this cell. Furthermore, we show that the COOH of nephrin interacts with the vesicular SNARE protein VAMP2 in vitro and ex vivo (using yeast-2 hybrid and coimmunoprecipitation studies). This work demonstrates a previously unsuspected role of nephrin in vesicular docking and insulin responsiveness of podocytes.
Diabetes 2007 Apr
PMID:Nephrin is critical for the action of insulin on human glomerular podocytes. 1739 51


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