Protective effect of diosmin against diabetic neuropathy in experimental rats

OBJECTIVE: The present study was undertaken to evaluate the effect of diosmin in diabetic neuropathy in type 2 diabetic rats. METHODS: Type 2 diabetes was induced in male Sprague-Dawley rats by single intraperitoneal injection of streptozotocin (35 mg/kg) and high-fat diet. Four weeks after the confirmation of diabetes, diabetic rats were treated with diosmin (50 and 100 mg/kg, p.o.) for next 4 weeks. Rats were evaluated for biochemical, behavioral and oxidative stress parameters. Eddy's hot plate and tail immersion test were performed on 6th, 7th, 8th, 9th and 10th weeks of experiment to assess thermal hyperalgesia and cold allodynia respectively. Further, the walking function test was performed for assessing the motor responses at the end of the treatment schedule. RESULTS: Rats were fed with high-fat diet throughout the experiment schedule and administration of low-dose streptozotocin induced significant elevation in blood glucose level and insulin resistance which was confirmed by oral glucose tolerance test. Treatment with diosmin at doses of 50 and 100 mg/kg significantly restored the reduced body weight, elevated blood sugar and lipid profiles. Further the dose-dependent improvement was observed in thermal hyperalgesia, cold allodynia and walking function in diabetic rats treated with diosmin. Elevated levels of malondialdehyde, and nitric oxide and decreased glutathione levels and superoxide dismutase activity in diabetic rats were restored significantly after the 4 weeks of diosmin treatment. CONCLUSION: Diosmin has shown beneficial effect in preventing the progression of early diabetic neuropathy in rats.