Abstract:

Objective To discuss the protective effect of ginsenoside Rh1 （G-Rh1） on kidney injury in the diabetic mellitus（DM） mice， and to clarify its mechanism. Methods The diabetic kidney disease （DKD） model was prepared by using the high-fat， high-sugar diet combined with intraperitoneal injection of streptozotocin （STZ）. A total of 48 C57/BL6 model mice were randomly divided into model group， nuclear factor erythroid 2-related factor 2 （Nrf2） inhibitor ML385 group （ML385 group） （30 mg·kg^-1）， G-Rh1 group （30 mg·kg^-1）， and G-Rh1+ML385 group （30 mg·kg^-1 G-Rh1+30 mg·kg^-1 ML385）， and there were 12 mice in each group. Additionally， 12 C57/BL6 mice were selected as control group. After treated for 8 weeks， automatic analyzer was used to detect the levels of fasting blood glucose （FBG）， blood urea nitrogen （BUN）， and serum creatinine （Scr） in serum of the mice in various groups， as well as 24 h urinary protein （24 h UP） levels in urine， and the kidney index was calculated； kits were used to detect the activities of superoxide dismutase （SOD） and lactate dehydrogenase （LDH）， and the levels of malondialdehyde （MDA） in kidney tissue of the mice in various groups； Western blotting method was used to detect the expression levels of Nrf2 and heme oxygenase-1 （HO-1） proteins in kidney tissue of the mice in various groups. Results Compared with control group， the levels of FBG and kidney indexes in serum of the mice in model group， ML385 group， and G-Rh1+ML385 group were significantly increased （P<0.01）， and the level of FBG in serum of the mice in G-Rh1 group was significantly increased（P<0.01）； compared with model group， the kidney index of the mice in ML385 group was significantly increased （P<0.05）， while the levels of FBG and kidney index of the mice in G-Rh1 group were significantly decreased （P<0.05 or P<0.01）； compared with G-Rh1 group， the level of FBG and kidney index of the mice in G-Rh1+ML385 group were significantly increased （P<0.01）. Compared with control group， the levels of BUN and Scr in serum， and 24 h UP in urine of the mice in model group， ML385 group， G-Rh1 group， and G-Rh1+ML385 group were significantly increased （P<0.01）； compared with model group， the level of BUN in serum and 24 h UP in urine of the mice in ML385 group were significantly increased （P<0.05）， while the levels of BUN and Scr in serum， and 24 h UP in urine of the mice in G-Rh1 group were significantly decreased （P<0.01）； compared with G-Rh1 group， the levels of BUN and Scr in serum， and 24 h UP in urine of the mice in G-Rh1+ML385 group were significantly increased （P<0.01）. Compared with control group， the activities of SOD in kidney tissue of the mice in model group， ML385 group， G-Rh1 group， and G-Rh1+ML385 group were significantly decreased （P<0.01）， while the levels of MDA and LDH activities were significantly increased （P<0.01）； compared with model group， the activity of SOD in kidney tissue of the mice in ML385 group was significantly decreased （P<0.05）， and the level of MDA was significantly increased （P<0.05）； the activity of SOD in kidney tissue of the mice in of G-Rh1 group was significantly increased （P<0.01）， and the level of MDA and activity of LDH were significantly decreased （P<0.01）； compared with G-Rh1 group， the activity of SOD in kidney tissue of the mice in G-Rh1+ML385 group was significantly decreased （P<0.01）， and the level of MDA and activity of LDH were significantly increased （P<0.01）. Compared with control group， the expression levels of Nrf2 and HO-1 proteins in kidney tissue of the mice in model group， ML385 group， G-Rh1 group， and G-Rh1+ML385 group were significantly decreased （P<0.05 or P<0.01）； compared with model group， the expression levels of Nrf2 and HO-1 proteins in kidney tissue of the mice in ML385 group and G-Rh1+ML385 group were significantly decreased （P<0.05）， while the expression levels of Nrf2 and HO-1 proteins in kidney tissue of the mice in G-Rh1 group were significantly increased （P<0.01）； compared with G-Rh1 group， the expression levels of Nrf2 and HO-1 proteins in kidney tissue of the mice in G-Rh1+ML385 group were significantly decreased （P<0.01）. Conclusion Ginsenoside Rh1 reduces the oxidative stress and improves the kidney function， providing protective effects on kidney injury in the DM mice， and its mechanism may be related to the activation of the Nrf2/HO-1 signaling pathway.

Key words: Ginsenoside Rh1, Diabetes, Kidney injury, Nuclear factor erythroid 2-related factor 2, Oxidative stress