Role of arginine, a component of aqueous garlic extract, in remediation of sodium arsenite induced toxicity in A375 cells

Arsenic contamination of ground water is emerging as a potential threat to human health. A report from our laboratory showed that aqueous garlic extract (AGE) had an extensive modulatory effect on arsenic toxicity. Moreover AGE formed a precipitate when incubated with NaAsO2 overnight. Mass spectral analysis showed arginine to be one component of AGE responsible for forming the precipitate with NaAsO2. We further confirmed the role of arginine in mitigation of arsenic toxicity in A375 cells. Incubation of A375 cells with NaAsO2 (10 mu M) for 24 h caused a reduction in cell viability, enhanced reactive oxygen species (ROS) production, a reduction of the activities of the intracellular enzymatic as well as non-enzymatic antioxidants and also an enhancement of lipid peroxidation. Arginine (60 mu M) along with NaAsO2 almost normalized the altered cell viability, modulated ROS level and activities of antioxidant indices. Arginine also blunted arsenic induced genotoxicity and elevated the expression of poly-ADP ribose polymerase.