ABSTRACT
Acute and chronic arsenic exposure results in toxicity in humans and causes many neurological and other manifestations. For the first time the present study reports that zinc decreases arsenic-induced apoptosis and also confirms a single report of apoptosis induced by arsenic in a neuronal cell line. Apoptosis measured by DEVD-caspase activity peaked between 10 microM and 20 microM of arsenic trioxide. Higher concentrations of arsenic up to 40 microM caused increasing cell death with diminishing DEVD-caspase activity. The beneficial effect of zinc was proportional to its concentration with a significant decrease in arsenic-induced DEVD-caspase activity at 50 microM and 75 microM zinc (P < 0.05). This finding may be of therapeutic benefit in people suffering from chronic exposure to arsenic from natural sources, a global problem especially relevant to millions of people on the Indian subcontinent.
