Urinary type IV collagen: a specific indicator of incipient diabetic nephropathy / 中华医学杂志(英文版)

<p><b>OBJECTIVE</b>To determine whether urinary type IV collagen can serve as an indicator specific for diabetic nephropathy.</p><p><b>METHODS</b>Using a novel sandwich ABC-ELISA to measure type IV collagen directly, the 24-hour urinary type IV collagen excretion rate was determined in 120 diabetic patients and some groups of controls. Urinary albumin determinations were made with a RIA kit at the same time. A total of 13 diabetic patients with microalbuminuria underwent percutaneous renal biopsy for definitive diagnosis of diabetic nephropathy. Type IV collagen and TGF-beta 1 immunoreactivities were detected with ABC methods in renal biopsies.</p><p><b>RESULTS</b>Urinary type IV collagen excretion was significantly increased in diabetic patients with microalbuminuria, especially those with albumin excretion above 200 mg/24 h. By comparison, collagen excretion was equivalent to that in healthy controls when measured in diabetics with normalbuminuria and in patients with primary glomerular disease, primary hypertension, or coronary heart disease. Urinary type IV collagen excretion in diabetics was negatively correlated with creatinine clearance. In renal biopsies from subjects with elevated collagen excretion, the glomeruli showed pathological changes typical of diabetic nephropathy. Also, excessive type IV collagen and TGF-beta 1 immunoreactivity were detected in the glomeruli, Bowman's capsule and interstitium.</p><p><b>CONCLUSIONS</b>Excretion of type IV collagen, possibly reflecting increased production or decreased degradation of this protein, may be a clinically useful indicator of incipient diabetic nephropathy.</p>

Prevalence of diabetic nephropathy of 1 059 cases with type 2 diabetes and its correlated risk factors / 中国糖尿病杂志

Opjective To study the prevalence of diabetic nephropathy of type 2 diabetes and its correlated risk factors. Methods 1 059 cases with type 2 diabetes in our university hospital during the period of 1997-2000 were screened for diabetic nephropathy,and its correlated risk factors were analysed. Results The prevalence of diabetic nephropathy and end stage of renal disease were 9.73% and 5.47%, respectively. Hypertension and dyslipidemia characterized with hypertriglycemia and low leve1 of HDL were the main risk factors of type 2 diabetic nephropathy. There was no significant relationship between single-determining HbAlc level and UAER. Conclusion The prevalence of diabetic nephropathy of this study was slightly lower than that reported by other authors in western countries,and the risk factors were consistent with those papers.

The role of transcription factor NF-kB in the INS-1 cell impairment induced by IL-1? and other cytokines / 中华内分泌代谢杂志

Objective To investigate the role of NF-kB in cytokines (IL-1?, TNF-? and IFN-r) -induced impairment of INS-1 cell, a pancreatic islet ?-cell line. Methods Retrovirus expressing IkB??N with mutant IkB?(inhibitor of NF-kB ) was constructed. Immunoblot analysis, fluorescence analysis using a kB-1uc reporter gene and thiazolyl blue viability assay were applied in this study. Results IL-1?-induced IkB? degradation and NF-kB activation were found in INS-1 cells but not in INS-1/IkB??N cells infected with IkB??N retrovirus. The viability of INS-1 cells incubated with the combination of IL-1? and IFN-r or TNF-? and IFN-r was decreased but INS-1/IkB??N cells could resist these cytokines-induced decrease of cell viability. Conclusion IL-1?, TNF-?can decrease the viability of? cells, while IFN-r may have some enhancing role. Inhibition of NF-kB activation can protect ? cells from the cytotoxicity of the cytokines.