SOLAMARGINE PURIFIED FROM SOLANUM-INCANUM CHINESE HERB TRIGGERS GENE-EXPRESSION OF HUMAN TNFR-I WHICH MAY LEAD TO CELL APOPTOSIS

Solamargine possessed a potent cytotoxicity to human hepatocyte (Hep3B ) and normal skin fibroblast. The inhibition curves of solamargine to the both cells were essentially overlapped, suggesting a parallel effe ct for the cell death. To define mechanism of cytotoxicity of solamarg ine, the changes of morphology and DNA content in cells were studied. A sub-G(1) cell stage was drastically increased after 3-h incubation w ith solamargine. The results evidence that solamargine arises cell dea th by apoptosis. In addition, the gene expression of TNFR I were up-re gulated within 30 min of solamargine treatment. Since TNF Receptor I h as been involved in apoptosis, the overexpression of TNF receptor I ma y be related with the mechanism of cytotoxicity of solamargine. This c ommunication is the first report that a component of Chinese herbs tri ggers gene expression of human TNFR I which may lead to cell apoptosis . (C) 1996 Academic Press, Inc.