[Mechanisms of prevention of progression of diabetic nephropathy by dietary protein restriction].
This study was designed to clarify the mechanisms by which the progression of diabetic nephropathy is inhibited by low-protein diet. Six control and twenty-five streptozotocin-induced diabetic rats were divided into 4 group: Group I consisted of non-diabetic control rats administered a 40% protein diet (n = 6); Group II, diabetic rats administered a 40% protein diet (n = 8); Group III, diabetic rats treated with a 10% protein diet (n = 8), and Group IV, diabetic rats treated together with a 10% protein diet and ad lib, drinking water containing 0.75 mg/l of angiotensin-converting enzyme inhibitor (ACEI) (n = 9). The follow-up period was 24 weeks. Urinary albumin excretion rate (AER), glomerular filtration rate (GFR) and morphometric measurement of renal biopsy specimens obtained at 12 and 24 weeks were evaluated. AER was significantly increased in the untreated diabetic Group II compared with the control Group I. However, AER was significantly decreased in the treated Group III and IV compared with the untreated diabetic Group II. There was no significant difference in AER between Group III and IV. Compared with Group II, the increase in GFR was significantly inhibited in Group IV but not in Group III. The increase in mesangial matrix and GBM thickening were both prominent in the untreated diabetic Group II, and significantly inhibited in the treated Group III and IV.(ABSTRACT TRUNCATED AT 250 WORDS)
Kobayashi
M
M
Department of Nephrology, Toho University School of Medicine.
D000418:Albumins / Q000378:metabolism; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000627:therapeutic use; D000818:Animals; D003921:Diabetes Mellitus, Experimental; D003928:Diabetic Nephropathies / Q000178:diet therapy* / Q000473:pathology / Q000503:physiopathology; D004044:Dietary Proteins / Q000627:therapeutic use*; D005500:Follow-Up Studies; D005919:Glomerular Filtration Rate; D007668:Kidney / Q000378:metabolism / Q000473:pathology; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D013311:Streptozocin
D000418:Albumins; D000806:Angiotensin-Converting Enzyme Inhibitors; D004044:Dietary Proteins; D013311:Streptozocin