Hydrogen sulfide alleviates neural degeneration in streptozotocin-induced diabetic rats probably through reducing oxidative stress and aldose reductase expression

Abstract

Background Diabetic peripheral neuropathy(DPN) is one of the most common complications of diabetes. In this study, we investigated the potential role of H2S as a novel therapy for DPN in diabetic rats. Method All the rats were divided into non-diabetic control group(n = 10), diabetic control group (n = 10) and H2S treated diabetic group (n = 10). A single dose of streptozotocin (60mg/kg) was applied to the rats for the diabetic models. Sodium bisulfide (50µmol/kg/d) was intraperitoneally injected daily for 2 weeks as H2S treatment. Biochemical assay, electromyogram, hematoxylin eosin (HE) staining, transmission electron microscopy, western blot and enzyme linked immunosorbent assay (ELISA) were then performed. Results H2S treatment did not affect the body weight, blood glucose levels or liver and kidney function in diabetic rats. Cell atrophy and axon degeneration of sciatic nerve and dorsal root ganglion (DRG) in diabetic rats were relieved after H2S treatment through observation of light microscopy and transmission electron microscopy. Furthermore, superoxide dismutase levels in serum and superoxide dismutase2 in sciatic nerve of diabetic rats were lower than non-diabetic rats, but restored obviously after H2S treatment. Serum and sciatic nerve homogenate malondialdehyde and aldose reductase expression were obviously higher in diabetic rats, but decreased significantly after H2S treatment. Finally, the sciatic nerve conduction velocity of diabetic rats improved after H2S treatment compared with diabetic control group, however without statistical significance. Conclusions Our study revealed that H2S alleviates neural degeneration in diabetic rats probably through reducing oxidative stress and downregulating aldose reductase expression.