Purification of antioxidant protein isolated from Peganum harmala and its protective effect against CCl4 toxicity in rats

Abstract

The present study was conducted to determine the protective effect of the purified protein from seeds of Peganum harmala against carbon tetrachloride (CCl_{4})-induced toxicity in male albino rats. The purification steps included ammonium sulfate fractionation and chromatography on DEAE-cellulose, CM-Sepharose, and Superdex 75 columns. The molecular mass of the purified protein was 132 kDa by gel filtration technique; it consisted of 2 subunits with molecular masses of 30.199 kDa and 38.018 kDa by SDS-PAGE. Results of the dose-dependent experiment with purified protein prior to CCl_4 administration were higher at 4 mg/kg body weight. The antioxidant activity of the purified protein was determined in vitro by DPPH radical scavenging test. Administration of CCl_4 significantly increased the activities of alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase in serum. However, a significant decrease in the level of total serum protein as well as the activities of superoxide dismutase, catalase, and reduced glutathione in liver tissues, and a significant increase in malondialdehyde level, were recorded. Pretreatment with 4 mg/kg body weight of the purified protein significantly altered the deteriorating damage induced by CCl_4 toxicity to a near normal range, which was similar to treatment with vitamin C. These results suggest that the purified protein possesses a protective effect against CCl_4-induced toxicity and probably acts as an antioxidative defense through free radical scavenging activity.