THE NEUROPROTECTIVE EFFECT OF BEE VENOM AGAINST DIABETIC NEUROPATHY IN A RAT MODEL: ULTRASTRUCTURE AND MORPHOMETRIC STUDY

Abstract

Context: Diabetes mellitus is a metabolic disorder characterized by hyperglycemia that accompanied by complications such as polyneuropathy. Bee venom (BV) therapy is an old traditional remedy that has been used to treat various diseases safely. Objectives: To evaluate the effect of BV on neuropathy of sciatic nerve in streptozotocin (STZ)-induced diabetes in rats using ultrastructure and morphometric methods. Materials and Methods: Thirty adult male Wister rats were divided randomly into (group I) the negative control group, (group II) the BV control group; rats received intraperitoneal injection (IP) of 0.5 mg/kg BV twice weekly for four consecutive weeks; (group III) the STZ-induced diabetic group and (group IV) was the BV treated group. Blood glucose levels were assessed for all groups twice weekly. At the end of fourth week, animals in all groups were sacrificed and the sciatic nerves of all groups were harvested and processed for semithin sections and ultrastructure study. Total fiber diameter, axon diameter, myelin thickness and the g ratio were measured and were statistically analyzed. Results: Blood glucose level was decreased to normal in BV treated group. Statistical analysis showed that treatment with BV significantly increased (P<0.05) sciatic nerve diameter in normal and diabetic rats and the g ratio was significantly decreased in diabetic rats. The ultrastructural examination revealed that BV reversed the axonal and myelin damage and degenerative changes of axonal mitochondria and Schwann cells that occurred in diabetic rats. Conclusion: BV therapy could protect against peripheral neuropathy resulting from STZ-induced hyperglycemia. KEYWORDS: Diabetic neuropathy, Bee venom, axon diameter, g ratio.