[Show abstract][Hide abstract] ABSTRACT: Problem statement: Diabetes mellitus occurs mainly with chronic polyneuropathy, and oxidative stress plays an important role in emergence of most neurologic and behavioral changes in diabetic patients. Many studies have focused on the beneficial effects of various antioxidants such as melatonin on diabetic neuropathy. The aim of this study is to evaluate the effect of melatonin in prevention of neuropathy in Streptozotocin-induced diabetic rats. After prescribing Streptozotocin (STZ), treatment rats received melatonin (10 mg kg day −1) or DMSO for a period of 6 weeks. Approach: At the end of the sixth week, non diabetic control group, diabetic control group (sham) and treated rats were examined by thermal pain response tests (hot plate and tail flick). The horizontal and vertical activities of rats were measured in an open field test. After that, Motor Nerve Conduction Velocity (MNCV) of sciatic-tibial nerve recorded. Also, to study morphological alterations resulting from diabetic neuropathy of sciatic nerve, Myelinated Fiber Diameter (MFD), Axon Diameter (AD) and Myelin Sheath Diameter (MSD) were evaluated by light microscope. Results: According to hot plate results, response time to thermal pain at the end of sixth week in sham group showed a significant decrease in comparison with the control group (p<0.01). In hot plate test, although melatonin approximated to the response time to control group, the significant difference was not observed among melatonin receivers and other groups. In the open field test, Total Distance Moved (TDM) and mobility duration showed significant decrease in sham and DMSO groups in comparison to the control and melatonin groups. Diabetic rats treated with melatonin showed significant increase in MNCV compared to sham and DMSO groups (p<0.05). In morphological study, pretreatment with Melatonin significantly reversed sciatic nerve diameters (MFD, AD, and MSD) reduction in diabetic rats. Electron microscopy showed myelin splitting and myelin sheath infolding in diabetic control group compare to non diabetic group. Conclusion: This study showed that melatonin can decrease the destructive progress of diabetes and causes neuroprotection against damages resulting from STZ-induced hyperglycemia.
American journal of pharmacology and toxicology 01/2011; 6:59-67.
[Show abstract][Hide abstract] ABSTRACT: To study the effects of an aqueous extract of date fruit (Phoenix dactylifera L. Arecaceae) diet on diabetic polyneuropathy (DPN) in streptozotocin- (STZ-) induced diabetic rats.
The effects of a date fruit extract (DFE) diet on diabetic neuropathy in STZ-induced diabetic rats were evaluated and compared with a nondiabetic control group, diabetic control group (sham), and vehicle group with respect to the following parameters: open field behavioral test, motor nerve conduction velocity (MNCV), and morphological observations.
In the model of STZ-induced of diabetic neuropathy, chronic treatment for 6 weeks with DFE counteracted the impairment of the explorative activity of the rats in an open field behavioral test and of the conduction velocity of the sciatic nerve (MNCV). In addition, pretreatment with DFE significantly reversed each nerve diameter reduction in diabetic rats.
DFE treatment shows efficacy for preventing diabetic deterioration and for improving pathological parameters of diabetic neuropathy in rats, as compared with control groups.
Oxidative Medicine and Cellular Longevity 01/2011; 2011:976948.