Hepatoprotective and antioxidant activity of Amaranthus spinosus against CCl4 induced toxicity

Aim: 50% ethanolic extract (ASE) of Amaranth us spinosus (whole plant) was evaluated for in vitro antioxidant and hepato protective activity. Methods: The total phenolics and reducing capacity of ASE was determined using standard curve of gallic acid (0-1.0 mg/ml) and butylated hydroxy anisole. In vitro antioxidant activity was determined by DPPH, superoxide, hydroxyl radicals, hydrogen peroxide and nitric oxide scavenging methods. The hepatoprotective activity of ASE was evaluated at 6, 7, 8, 9 and 10 mu g/ml concentration against CCl4 (1%) induced toxicity in freshly isolated rat hepatocytes and HepG2 cells. Results: ASE was found to contain 336 +/- 14.3 mg/g total polyphenolics expressed as gallic acid equivalent while the reducing capacity was 2.26 times of BHA. ASE showed significant antioxidant activity in DPPH assay (IC50 29 mu g/ml), scavenges superoxide (IC50 similar to 66-70 mu g/ml). hydrogen peroxide (IC50 similar to 120-125 mu g/ml), hydroxyl radicals (IC50 similar to 140-145 mu g/ml) and nitric oxide (IC50 similar to 135-140 mu g/ml). ASE (6, 7, 8, 9 and 10 mu g/ml) was able to normalise the levels of biochemical parameters in isolated rat hepatocytes intoxicated with CC14. A dose dependent increase in percentage viability was observed in CCl4 intoxicated HepG2 cells. Conclusions: ASE possesses significant hepatoprotective activity which might be due to antioxidant defence factors and phenolics might be the main constituents responsible for activity. (C) 2009 Elsevier Ireland Ltd. All rights reserved.