Protective effect of alpha lipoic acid on rat sciatic nerve ischemia reperfusion damage

Abstract

Background: Alpha lipoic acid is a potent antioxidanthat plays numerous roles in human health. This studyexamined the effect of ALA on rat sciatic nerve isch- emia reperfusion damage. Aims: Protective effect of alpha lipoic acid (ALA) onsciatic nerve following ischemia-reperfusion in ratswas investigated by using light microscopy and bio- chemical methods. Provided that the protective effectof ALA on sciatic nerve is proven, we think the damageo the sciatic nerve that has already occurred or mightoccur in patients for various reasons maybe preventedor stopped by giving ALA in convenient doses. Study Design: Animal experiment. Methods: Forty-two adult male Sprague-Dawley rats250-300 grams) were used in this study. Rats wereandomly divided into six groups including one con- rol (Group 1), one sham (Group 2), two ischemia-re- perfusion (Groups 3 and 4) and two treatment groupsGroups5 and 6). Doses of 60 and 100 mg/kg ALA weregiven (Group 5 and 6) intra peritoneally twice, 1 and24 hours before the ischemia to each treatment group.schemia was carried out the abdominal aorta startingfrom the distal part of the renal vein for two hours fol- owed by reperfusion for three hours. In immunohisto- chemical methods, fibronectin immunoreactivity wasanalyzed. For biochemical analyses, the tissues were taken in eppendorf microtubes and superoxide dis-mutase (SOD) and glutathione peroxidase (GSHPx)enzyme activities as well as malondialdehyde (MDA)and nitricoxide (NO) levels were measured.Results: Fibronectin was observed to have increasedsignificantly in the ischemia group; on the other hand,it was observed to have decreased in parallel to the dos-es in the ALA groups. Biochemical studies showed thatSOD and GSHPx declined with ischemia-reperfusion,but the activities of these enzymes were increased inthe treatment groups in parallel with the dose. It wasfound that increased MDA levels with ischemia-reper-fusion were decreased in parallel with ALA dose. Therewere no statistically significant changes in NO.Conclusion: Increased fibronectin observed after isch-emia/reperfusion of rat sciatic nerve is reduced afterthe administration of ALA. This indicates that the func-tion of fibronectin, to reconnect cut nerve segments andregenerate nerves, is more prominent than its functionin tissue healing after ischemia. ALA administered be-fore ischemia decreases MDA and increases SOD andGSHPx. We think that ALA may protect against thepathological changes in ischemic nerve and may beused to devise more efficient treatments.