Cytotoxicity of 7-Ketocholesterol on Cultured Rat Hepatocytes and Cytoprotection by Vitamin E

Abstract

The effects of 7-ketocholesterol on rat hepatocytes prepared by collagenase perfusion were examined. The addition of 7-ketocholesterol to the culture medium increased the relative ratio of total sterol to phospholipid of hepatocytes significantly in a time-dependent manner without changing the phospholipid content. And vitamin E suppressed the incorporation of 7-ketocholesterol into hepatocytes significantly. Although hepatocytes treated with 7-ketocholesterol produced a larger amount of O₂^-at the early stage of incubation than those treated with cholesterol, lipid peroxidation was not observed. When hepatocytes were treated with 7-ketocholesterol, vitamin E might prevent the hepatocytes from cell death not only by suppressing the incorporation of 7-ketocholesterol into hepatocytes but by scavenging O₂^-.