EFFECTS OF SIMVASTATIN AND ALPHA-TOCOPHEROL ON DISTURBED NERVE CONDUCTION IN OBESE SPRAGUE DAWLEY RATS
AbstractBackground: The incidence of obesity is increasing worldwide. The neuropathy associated withobesity, that is evident from disturbed nerve conduction, is one of the complications for which anumber of treatment options are being considered. In this study, Simvastatin, a hydroxyl methylglutaryl coenzyme A reductase inhibitor and alpha-tocopherol, a dietary antioxidant are comparedfor their effects on sciatic nerve conduction velocity. Objectives: To compare the effects ofSimvastatin and alpha-tocopherol on sciatic nerve conduction velocity in obese rats. Methods:The study was a Randomised control trial conducted from December 2008 to November 2009.One hundred and twenty adult male Sprague Dawley rats were divided into four groups with 30rats in each group. One group of rats was taken as control with normal diet while other threegroups were given high fat diet (HFD) for the whole study period. Along with the high fat diet,group III and group IV were given Simvastatin and alpha-tocopherol supplemented dietrespectively. At the end of study, conduction velocity of sciatic nerve was determined with thehelp of PowerLab® data acquisition system. Results: The three groups with HFD showed morethan 25% increase in weight at the end of study compared to control group. The control groupwith high fat diet (Group II) showed decreased sciatic nerve conduction velocity when comparedwith control (Group I). Both the groups that were given Simvastatin and alpha-tocopherol eachshowed improvement in sciatic nerve conduction velocity (p<0.001) after four weeks whencompared with the group that was given HFD without any supplementation. However with alphatocopherol, the nerve conduction velocity was improved more significantly. Conclusions:Simvastatin and alpha-tocopherol both are effective for improving sciatic nerve conductionvelocity in HFD induced obesity.Keywords: Obesity, Simvastatin, nerve conduction velocity, alpha-tocopherol, High Fat Diet
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