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

We found that peroxisome proliferator-activated receptor-gamma (PPARgamma) mRNA was reduced by 77% in glomeruli of diabetic mice. Because mesangial cells play an important role in diabetic nephropathy, we examined regulation of type I collagen expression by PPARgamma and transforming growth factor-beta(1) (TGF-beta(1)) in mouse mesangial cells in the presence of 6 and 25 mM glucose. Mesangial cells contained functionally active PPARgamma. Exposure to 25 mM glucose resulted in reduced PPARgamma expression and transcriptional activity, accompanied by increased type I collagen expression. Restoration of PPARgamma activity to normal levels in cells cultured in 25 mM glucose, by transfection with a PPARgamma expression construct and treatment with the PPARgamma agonist troglitazone, returned type I collagen levels toward normal values. Activation of PPARgamma by troglitazone also decreased type I collagen mRNA and blocked TGF-beta(1)-mediated upregulation of type I collagen mRNA and protein. Moreover, PPARgamma activation suppressed basal and activated TGF-beta(1) responses in mesangial cells. This action was blocked by transfection of cells with a dominant-negative PPARgamma construct. In summary, PPARgamma suppresses the increased type I collagen mRNA and protein expression mediated by TGF-beta(1) in mesangial cells.
 ...
PMID:Upregulation of type I collagen by TGF-beta in mesangial cells is blocked by PPARgamma activation. 1188 Mar 25

The Pro12Ala polymorphism of the gene encoding the peroxisome proliferator-activated receptor (PPAR)-gamma2 has recently been shown to be associated with type 2 diabetes. In the present analysis, we investigated whether PPAR-gamma2 Pro12Ala was associated with microvascular complications of type 2 diabetes, such as albuminuria, end-stage renal failure (ESRF), or retinopathy. A total of 445 patients with type 2 diabetes who were enrolled in the Berlin Diabetes Mellitus Study and in whom we determined albuminuria and the presence of ESRF and retinopathy were genotyped for the PPAR-gamma2 Pro12Ala polymorphism. We also measured potentially important covariables, such as blood pressure, BMI, duration of diabetes, glycosylated hemoglobin, serum creatinine, and serum lipids. Among 445 patients with type 2 diabetes (mean age 59.3 years), the Pro12Ala genotype distribution was in Hardy-Weinberg equilibrium (P = 0.42). The Ala12 allele frequency was 0.14. With adjustment for covariables, the 118 Ala12 allele carriers had significantly lower urinary albumin excretion (UAE) than the 327 noncarriers (17.1 vs. 25.8 mg/d; P = 0.01). The percentage decrease in UAE observed in PPAR-gamma Ala12 allele carriers relative to noncarriers (P = 0.003) rose from 0.2% (P = 0.99) to 54% (P = 0.008) and to 70% (P = 0.01) when the duration of diabetes increased from <10 years to 10-19 years and to >or=20 years, respectively. Similarly, the odds ratios of having albuminuria decreased from 1.22 (P = 0.54) to 0.61 (P = 0.23) and to 0.11 (P = 0.007), respectively. Among patients with type 2 diabetes, PPAR-gamma2 Ala12 allele carriers had significantly lower UAE and tended to develop overt proteinuria less frequently. These observations suggest a protective effect of the Ala12 allele in relation to diabetic nephropathy.
 ...
PMID:Peroxisome proliferator-activated receptor-gamma2 polymorphism Pro12Ala is associated with nephropathy in type 2 diabetes: The Berlin Diabetes Mellitus (BeDiaM) Study. 1214 84

The peroxisome proliferator-activated receptor gamma2 (PPARgamma2) Pro12Ala polymorphism has been associated with a decreased risk of type 2 diabetes and a lower albumin excretion rate (AER) in patients with established diabetes. We performed a case-control study aiming to evaluate the association between the Pro12Ala polymorphism and diabetic nephropathy. Genomic DNA was obtained from 104 type 2 diabetic patients (case subjects) with chronic renal insufficiency (78 on dialysis and 26 with proteinuria [AER >or=200 microg/min] and serum creatinine >or=2.0 mg/dl) and 212 normoalbuminuric patients (AER <20 microg/min) with known diabetes duration >or=10 years (control subjects). The genotypic distribution of the PPARgamma2 Pro12Ala polymorphism in these diabetic patients was in Hardy-Weinberg equilibrium, and the Ala allele frequency was 9%. The frequency of Ala carriers (Ala/Ala or Ala/Pro) was 20.3% in control subjects and 10.6% in case subjects (P = 0.031). The odds ratio of having diabetic nephropathy for Ala carriers was 0.465 (95% CI 0.229-0.945; P = 0.034). Carriers of the Ala allele were not different from noncarriers (Pro/Pro) regarding sex (38.9 vs. 44.1% males) or ethnicity (77.4 vs. 71.7% white) distribution, age (61 +/- 10 vs. 61 +/- 10 years), known diabetes duration (17 +/- 7 vs. 16 +/- 7 years), BMI (27 +/- 4 vs. 28 +/- 5 kg/m(2)), fasting plasma glucose (184 +/- 81 vs. 176 +/- 72 mg/dl), HbA(1c) (6.7 +/- 2.3 vs. 6.9 +/- 2.4%; high-performance liquid chromatography reference range: 2.7-4.3%), and systolic (145 +/- 27 vs. 0.144 +/- 24 mmHg) or diastolic (87 +/- 14 vs. 85 +/- 14 mmHg) blood pressure, respectively. In conclusion, the presence of the Ala allele may confer protection from diabetic nephropathy in patients with type 2 diabetes.
 ...
PMID:The human peroxisome proliferator-activated receptor gamma2 (PPARgamma2) Pro12Ala polymorphism is associated with decreased risk of diabetic nephropathy in patients with type 2 diabetes. 1463 65

NIP-222 is a novel peroxisome proliferator-activated receptor (PPAR)gamma agonist. This study provides evidence that NIP-222 decreases urinary albumin excretion (UAE) in diabetic mice independent of its PPARgamma activation. We compared the effect of NIP-222 and another PPARgamma agonist, troglitazone, on UAE, plasma glucose level, blood pressure, and creatinine clearance (C(cr)) in streptozotocin (STZ)-induced diabetic mice. Treatment for 3 weeks with NIP-222 (30 mg/kg) was associated with a significant decrease in UAE without any change in blood pressure, creatinine clearance, or plasma glucose level. In contrast, UAE did not decrease in mice treated with troglitazone (300 mg/kg). These results indicate that NIP-222 has PPARgamma independent effects on UAE in diabetic mice and suggest that this agent may have potential to minimize the development and progression of diabetic nephropathy.
 ...
PMID:A novel peroxisome proliferator-activated receptor (PPAR)gamma agonist, NIP-222, reduces urinary albumin excretion in streptozotocin-diabetic mice independent of PPARgamma activation. 1466 69

It is generally considered that genetic factors may contribute to the susceptibility of type 2 diabetic nephropathy. The purpose of the present study is to identify molecules that contribute to the development and/or progression of this disease. Differential display was performed to isolate genes in the kidney using the KK/Ta mouse model of type 2 diabetes. The differential expression of 8 randomly chosen candidate genes (DN1-8) were verified by reverse-transcriptase polymerase chain reaction (RT-PCR) or Northern blot analysis. DN1-3 (Zn-alpha2-glycoprotein, vascular endothelial growth factor receptor [VEGFR]-2, and lactate dehydrogenase [LDH]) were overexpressed and DN7-8 (peroxisome proliferator-activated receptor [PPAR]-interacting protein [PRIP], unknown) were underexpressed in the KK/Ta mouse kidney. DN4-6 (Ezrin, transcobalamin 2, aldo-ketoreductase) did not differ between KK/Ta and control (BALB/c) mice. DN8 only showed no significant sequence similarity to previously reported genes. Molecular cloning revealed that full-length DN8 shares 89% identity with human cholinephosphotransferase 1 (hCHPT1), and we designated it as "putative" mouse cholinephosphotransferase 1 (mCHPT1). The putative mCHPT1 gene was most closely mapped to the D10Mit94 locus with the highest logarithm of odds (lod) score. In situ hybridization revealed the levels of glomerular putative mCHPT1 in BALB/c mice tended to be slightly higher than those in KK/Ta mice. The altered renal mRNA expression of these genes may be involved in the development and/or progression of diabetic nephropathy.
 ...
PMID:Altered mouse cholinephosphotransferase gene expression in kidneys of type 2 diabetic KK/TA mouse. 1525 74

Lipid-mediated injury plays an important role in the pathogenesis of many renal diseases including diabetic nephropathy. Liver X receptor-alpha (LXRalpha) is an intracellular sterol sensor that regulates expression of genes controlling cholesterol absorption, excretion, catabolism, and cellular efflux. The present study was aimed at examining the role of LXRalpha in cholesterol metabolism in glomerular mesangial cells. A 1,561-bp fragment of full-length rabbit LXR cDNA was cloned. The deduced protein sequence exhibited 92.4 and 89.2% identity to human and mouse LXRalpha, respectively. Tissue distribution studies showed that rabbit LXRalpha was expressed in the liver, spleen, and kidney. In situ hybridization and RT-PCR assays further indicated that LXRalpha mRNA was widely expressed in the kidney and present in every nephron segment including the glomeruli. To determine intrarenal regulation of LXRalpha, rabbits were treated with thiazolidinedione (TZD) peroxisome proliferator-activated receptor-gamma (PPARgamma) agonists, which have been previously shown to enhance LXRalpha expression via PPARgamma and increase cholesterol efflux in macrophages. The results showed that glomerular LXRalpha expression was markedly induced by TZDs. In cultured rabbit mesangial cells, LXRalpha mRNA and protein were detected by RT-PCR and immunoblotting. Treatment of mesangial cells with a specific LXRalpha agonist, TO-901317, significantly increased basal and apolipoprotein AI-mediated cholesterol efflux and markedly enhanced the promoter activity of an LXRalpha target gene, ATP-binding cassette transporter A1 (ABCA1). In conclusion, LXRalpha is expressed in renal glomeruli and functionally present in mesangial cells where its activation mediates cholesterol efflux via ABCA1. These data suggest that LXRalpha may be a potential therapeutic target for treating lipid-related renal glomerular disease.
 ...
PMID:Liver X receptor-alpha mediates cholesterol efflux in glomerular mesangial cells. 1528 Jan 60

Diabetic nephropathy is a clinical syndrome of albuminuria, declining glomerular filtration rate, and increased risk of cardiovascular disease. Multiple mechanisms have been implicated in its pathogenesis. Although current therapies appear to be effective, treatment of diabetic nephropathy remains suboptimal. This review summarizes the recently emerging evidence suggesting that peroxisome proliferator-activated receptor-gamma agonists may prove to be effective therapeutic agents in the treatment of diabetic renal complications.
 ...
PMID:PPAR-gamma agonists and diabetic nephropathy. 1631

Fibrate peroxisome proliferator-activated receptor (PPAR)-alpha ligands are mainly used as hypolipidemic drugs. But this commentary highlights their potential in treating insulin resistance, dyslipidemia, and hypertension and in preventing diabetic nephropathy, inflammation, and cardiovascular disease. Because diabetes is a major contributor to chronic kidney disease and cardiovascular disease, PPAR-alpha agonists may provide greater opportunities for hitting multiple targets in this complex metabolic disease.
 ...
PMID:The PPARalpha ligand fenofibrate: meeting multiple targets in diabetic nephropathy. 1667 21

Thiazolidinediones are ligands for peroxisome proliferator-activated receptor (PPAR)-gamma, widely used as insulin sensitizer in type 2 diabetic patients and implicated in apoptosis, cell proliferation, and cell cycle regulation. Here, the effect of thiazolidinediones on G1-phase cell cycle arrest, the hallmark in diabetic nephropathy, was investigated. Eight-week-old male Otsuka Long-Evans Tokushima fatty rats were treated with pioglitazone (1 mg x kg body wt(-1) x day(-1)) until 50 weeks of age and compared with insulin treatment. Although similar HbA(1c) levels were observed in both groups, pioglitazone significantly inhibited glomerular hypertrophy and mesangial matrix expansion and reduced urinary albumin excretion compared with the insulin-treated group. In addition, pioglitazone significantly reduced the number of glomerular p27(Kip1)-positive cells. Because prominent expression of PPAR-gamma was observed in podocytes in glomeruli and cultured cells, conditionally immortalized mouse podocyte cells were cultured under 5.5 and 25 mmol/l D-glucose supplemented with pioglitazone. Pioglitazone inhibited cell hypertrophy revealed by [(3)H]thymidine and [(3)H]proline incorporation, and pioglitazone reversed high glucose-induced G1-phase cell cycle arrest, i.e., an increase in G0/G1 phase and decrease in S and G2 phases. Pioglitazone suppressed high glucose-induced phosphorylation of p44/42 mitogen-activated protein kinase and reduced Bcl-2 and p27(Kip1) protein levels. Besides glucose-lowering action, pioglitazone ameliorates diabetic nephropathy via cell cycle-dependent mechanisms.
 ...
PMID:Thiazolidinediones ameliorate diabetic nephropathy via cell cycle-dependent mechanisms. 1673 29

In Akita and OVE26 mice, two genetic models of type 1 diabetes, diabetic nephropathy is characterized by mesangial expansion and loss of podocytes, resulting in glomerulosclerosis and proteinuria, and is associated with increased expression of profibrotic growth factors, proinflammatory cytokines, and increased oxidative stress. We have also found significant increases in renal triglyceride and cholesterol content. The increase in renal triglyceride content is associated with 1) increased expression of sterol regulatory element-binding protein (SREBP)-1c and carbohydrate response element-binding protein (ChREBP), which collectively results in increased fatty acid synthesis, 2) decreased expression of peroxisome proliferator-activated receptor (PPAR)-alpha and -delta, which results in decreased fatty acid oxidation, and 3) decreased expression of farnesoid X receptor (FXR) and small heterodimer partner (SHP). The increase in cholesterol content is associated with 1) increased expression of SREBP-2 and 3-hydroxy-3-methylglutaryl (HMG)-CoA reductase, which results in increased cholesterol synthesis, and 2) decreased expression of liver X receptor (LXR)-alpha, LXR-beta, and ATP-binding cassette transporter-1, which results in decreased cholesterol efflux. Our results indicate that in type 1 diabetes, there is altered renal lipid metabolism favoring net accumulation of triglycerides and cholesterol, which are driven by increases in SREBP-1, ChREBP, and SREBP-2 and decreases in FXR, LXR-alpha, and LXR-beta, which may also play a role in the increased expression of profibrotic growth hormones, proinflammatory cytokines, and oxidative stress.
 ...
PMID:Regulation of renal fatty acid and cholesterol metabolism, inflammation, and fibrosis in Akita and OVE26 mice with type 1 diabetes. 1693 98


1 2 3 4 5 6 Next >>