Comparison of the hepatotoxicity of toxin T-514 of Karwinskia humboldtiana and its diastereoisomer in primary liver cell cultures.

Toxin T-514 of Karwinskia humboldtiana has been demonstrated to be hepatotoxic in vivo and in vitro. Recently a diastereoisomer of T-514 has been isolated. In the present study we have evaluated and compared the in vitro hepatoxicity of the diastereoisomer of T-514 using primary cultures of rat hepatocytes. Cytotoxicity was evaluated by release of cytoplasmic enzyme lactate dehydrogenase (LDH), and mitochondrial metabolic function (MTT reduction). The diastereoisomer was shown to be almost as hepatoxic in vitro as toxin T-514.