Total Antioxidant Status and Antioxidant Enzymes in Cyclosporine Treated Rats

Abstract

Oxygen free radicals can be defined as oxygen molecules or molecular fragments that have an unpaired electron.1 and 2 They are formed in all living organisms during physiologic and pathophysiologic metabolism1 and 2 and cause cell and tissue damages due to their high chemical reactivity.1 and 2 These oxygen free radicals contribute to cyclosporine (CsA)-induced toxicity, including nephrotoxicity3, 4, 5 and 6 and hepatotoxicity.6 and 7 Against damage by active oxygens, aerobic cells are protected by several antioxidants,1 and 8 including antioxidant enzymes, vitamin C, vitamin E, ceruloplasmin, and glutathione.1 The decreased efficiency of several antioxidants or the increased production of oxygen free radicals results in damages mediated by oxygen free radicals. There are a lot of antioxidants, and a lot of factors that affect antioxidants, including antioxidant-associated trace metals such as selenium, copper, and zinc.1

To estimate the protecting ability against damage by oxygen free radicals in CsA-treated rats, the antioxidant status and three well-known antioxidant enzymes such as superoxide dismutase, glutathione peroxidase, and catalase were measured in the plasma of CsA-treated rats. The level of malondialdehyde, which gives an indirect index of oxidative injury,9 was also measured.