Carotenoids protect cultured rat hepatocytes from injury caused by carbon tetrachloride

Carotenoids are proposed to have antioxidant activities. The present study was therefore designed to determine whether carotenoids have a protective effect on CCl₄-induced hepatocyte injury in vitro. Primarily cultured rat hepatocytes were exposed to medium containing the carotenoids (α-carotene, β-carotene, lycopene and lutein) (10^-7-10^-5 M) with or without CCl₄ (1.5 mM). The release of glutamic pyruvic transaminase and lactic dehydrogenase into medium and the formation of malondialdehyde were examined as indices of cell injury. CCl₄ induced the release of glutamic pyruvic transaminase and lactic dehydrogenase into the medium in a dose-dependent fashion. All the carotenoids studied protected cultured rat hepatocytes from CCl₄-induced injury based on a reduction of glutamic pyruvic transaminase and lactic dehydrogenase release into the medium and suppression of lipid peroxidation. They also improved the survival of hepatocytes. This study suggests that α-carotene, β-carotene, lycopene and lutein have protective effects on oxidant-induced injury of hepatocytes.