Regulation of C-type natriuretic peptides and natriuretic peptide receptor-B expression in diabetic rats renal treated by Tongluo Recipe / 中国结合医学杂志

<p><b>OBJECTIVE</b>To investigate the expression of C-type natriuretic peptides (CNP) and natriuretic peptide receptor-B (NPR-B) receptor in diabetic rats renal cortex, and the regulation by Tongluo Recipe (TLR).</p><p><b>METHODS</b>Sixty male SD rats were divided into 3 groups: the normal control group, diabetic model group and diabetic TLR group. Each group was further divided into two subgroups of ten in each, according to 4-week or 12-week observation period. Streptozotocin (STZ)-induced diabetic rats were treated with TLR (1.0 g·kg(-1)·d(-1)) for 4 and 12 weeks, respectively. (1) The essential information was collected for comparing renal mass, serum creatinine and 24 h urine albumen on each group was calculated. (2) CNP mRNA and NPR-B mRNA were detected by realtime-polymerase chain reaction (PCR) on rats renal cortex. (3) Concentration of CNP on renal cortex or serum were analyzed by enzyme-linked immunosorbent assay (ELISA). (4) Pathological evaluation and NPR-B immunostaining for renal tissue were also performed.</p><p><b>RESULTS</b>(1) CNP and NPR-B mRNA levels were detected in each treated or untreated group, with slight elevated in untreated diabetes rats administrated with STZ after 4-week and CNP mRNA level remarkable elevated at 39.21 times higher than normal control group after 12 weeks, but NPR-B mRNA level showed a remarkably down-regulation at 98.07% after 12 weeks. CNP mRNA of TLR-treated group was also elevated after 12-week treatment, but less than untreated group. (2) Concentrations of CNP in renal cortex were obviously increased in treated or untreated diabetes rats, within these groups the treatment of TLR was found more significantly on prompting CNP concentration. Comparing to normal group, serum concentrations of CNP were also increased in treated or untreated diabetic groups, but there was no difference between these diabetic groups. (3) Renal lesions like glomerular volume increased are observed mostly in the relative early stage after 4 weeks. Although TLR treated group had no significant difference in their glomerular volume, the degrees of injury of glomerulus were ameliorated, as well as the NPR-B immunostaining enhanced in glomerulus. Weakly positive immunostaining of NPR-B are observed in glomerulus of normal control, and negative in glomerulus of untreated diabetes rats administrated with STZ after 12 weeks, whereas TLR-treatment groups showed a little enhancement.</p><p><b>CONCLUSION</b>CNP and NPR-B showed different characteristic on renal cortex at different pathological period in diabetes rats, and TLR regulated their expression.</p>

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

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.

Effects of Tongluo recipe on injury of glomerular visceral epithelial cells in streptozotocin-induced diabetic rats / 第二军医大学学报

Objective To investigate the therapeutic effects and the possible mechanisms of Tongluo reiipe (TLR) on podocyte injury in streptozotocin-induced diabetic rats. Methods Diabetes was induced by a ingle intraperitoneal injection of streptozotocin (60 mg/kg) dissolved in citrate buffer. The diabetic model rats were randomly divided into two groups (n=12): diabetic mellitus (DM) group and DM+TLR group. Rats in the DM+TLR group received 0. 4 g/(kg · d) TLR throughout the experiment. Rats in the DM group and CON group (n=8) were given celiac perfusion of distilled water once at the same time and dose. After 12-week treatment, 24 h urinary protein of rats was determined; the cellular ultrastructures of podocytes were observed by transmission electronic microscope; 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 superoxíde dismutase (SOD), glutathione peroxidase (GSH-Px) and the content of malondialdehyde (MDA) were measured in the plasma and renal cortical tissue. Resulls Compared with CON group, DM group and DM+TLR group had significantly increased ratio of kidney mass to body mass, blood glucose, and 24-h proteinuria (all P<0.01); at the 12th week, the glomerular basement membrane in DM group became conspicuously thick, foot process fusion and microvilli of podocytes were observed, and nephrin expression, podocyte number and podocyte density in the glomerulis were all significantly decreased (P<0.01). The morphology of the foot process was almost normal in DM+TLR group, with the basement membrane thickened, but was slighter than that in the DM group; and nephrin expression, podocyte number and podocyte density in DM+TLR group were significantly higher than those in the DM group (P<0.01). Compared with CON group, DM group and DM+TLR group had significantly increased MDA content, and significantly decreased SOD and GSH-Px activities in the plasma and renal cortical tissue (P<0.01, P<0.05). Compared with DM group, DM+TLR group had significantly increased SOD and GSH-Px activities and significantly decreased MDA content in plasma and renal cortical lissue(P<0.01, P< 0.05). Conclusion TLR can ameliorate podocyte injury probably through depleting free radical production and increasing activities of anfioxidatant.

Effects of tongluo recipe on injury of glomerular visceral epithelial cells in streptozotocin-induced diabetic rats / 第二军医大学学报

Objective To investigate the therapeutic effects and the possible mechanisms of Tongluo recipe(TLR) on podocyte injury in streptozotocin-induced diabetic rats. Methods Diabetes was induced by a single intraperitoneal injection of streptozotocin(60 mg/kg) dissolved in citrate buffer. The diabetic model rats were randomly divided into two groups(n=12): diabetic mellitus(DM) group and DM+TLR group. Rats in the DM+TLR group received 0. 4 g/(kg • d) TLR throughout the experiment. Rats in the DM group and CON group (n = 8) were given celiac perfusion of distilled water once at the same time and dose. After 12-week treatment, 24 h urinary protein of rats was determined; the cellular ultrastructures of podocytes were observed by transmission electronic microscope; the number and the density of podocytes in glomerulis were measured by stereo logical dissector/fractionatormethods; the expression of nephrin in renal cortical tissuewas 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 tissue. Results Compared with CON group, DM group and DM+TLR group had significantly increased ratio of kidney mass to body mass, blood glucose, and 24-h proteinuria(all P<0. 01); at the 12th week, the glomerular basement membrane in DM group became conspicuously thick, foot process fusion and microvilii of podocytes were observed, and nephrin expression, podocyte number and podocyte density in the glomerulis were all significantly decreased(P < 0. 01). The morphology of the foot process was almost normal in DM+TLR group, with the basement membrane thickened, but was slighter than that in the DM group; and nephrin expression, podocyte number and podocyte density in DM+TLR group were significantly higher than those in the DM group(P<0. 01). Compared with CON group, DM group and DM+TLR group had significantly increased MDA content, and significantly decreased SOD and GSH-Px activities in the plasma and renal cortical tissue (P<0. 01, P<0. 05). Compared with DM group, DM+TLR group hadsignificantly increased SOD and GSH-Px activities and significantly decreased MDA content in plasma and renal cortical tissue(P<0. 01, P< 0.05). Conclusion TLR can ameliorate podocyte injury probably through depleting free radical production and increasing activities of antioxidatant.