Protective effects of Tongluo recipe against injury of glomerular visceral epithelial cells in diabetic rats / 第二军医大学学报

ABSTRACT

Objective: To observe the protective effect of α-lipoic acid (ALA) and Tongluo recipe(TLR) against injury of glomerular visceral epithelial cells in diabetic rats, so as to discuss the possible mechanism for injury of glomerular visceral epithelial cells in diabetes. Methods: Rat diabetes model was induced by high-fat diet and a single intraperitoneal injection of streptozotocin (35 mg/kg). The diabetic model rats were randomly divided into three groups (n = 8) diabetes mellitus (DM) group, DM+TLR and DM+ALA group; another 8 rats served as normal controls (CON group). Rats in the DM+TLR group received 0.4 g • kg-1 • d-1 TLR and DM+ALA group received 0. 1 g • kg-1 • d-1 ALA throughout the experiment. Rats in the DM group and control (CON) group were given celiac perfusion of distilled water once at the same time and volume. After 12 weeks of treatment, kidney mass/body mass index, 24 h urinary protein, blood urea nitrogen, and urinary albumin/Cr were determined in each group. The number and the density of podocytes in glomerulis were measured by stereological dissector/ fractionator methods. The expression of nephrin in renal cortical tissue was detected by Western blotting analysis. The activity of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and the content of malondialdehyde (MDA)were measured in the plasma and renal cortical tissues. Results: After 12 weeks, the kidney mass/body mass index, 24 h urinary protein and urinary albumin/Cr in DM group were significantly increased compared to control group (P<0. 01); the number and density of podocytes in the glomerulis and nephrin expression in DM group were significantly decreased (P<0. 01). The kidney mass/ body mass index, 24 h urinary protein and urinary albumin/Cr in DM+TLR and DM+ALA groups were significantly decreased compared to DM group (P<0. 01); the number and density of podocytes and nephrin expression in DM+TLR and DM+ALA groups were significantly increased compared to DM group (P<0. 01, P<0. 05). GSH-Px and SOD activities were significantly decreased in the plasma (P<0. 01) and renal cortical tissue (P<0. 01) in DM, DM+ALA and DM+TLR groups compared to those in the CON group, and the content of MDA was significantly increased (P<0. 01, P<0. 05). GSH-Px and SOD activities were significantly increased in the plasma and renal cortical tissue (P both<0. 01) and MDA content was significantly decreased in DM+TLR and DM+ALA groups (P<0. 01, P<0. 05)compared to those in the DM group. No significant differences were found between DM + ALA group and DM + TLR group concerning the above parameters. Conclusion: TLR can ameliorate podocyte injury in diabetic rats, which might be associated with its anti-oxidative effect.