Abstract
The cytotoxicity of rubratoxin B was studied in human hepatoma cell HepG2, human uterine tumor cell HeLa and mouse ascites tumor cell Ehrlich. Exposure to rubratoxin B resulted in the cultured cells to be shrunk, and their volumes reduced. The inhibitory dose 50% (ID50) of the water soluble tetrazolium-1 assay (Wst-1; measurement of the activity of mitochondrial enzyme) were 2-to 3.6-fold of those of bromo-deoxyuridine incorporation (BrdU ; measurement of the activity of replication). Rubratoxin B did not affect the cell cycle, but brought about a dose-dependent increase of degraded chromosomal DNA. The reduction of cell volume and the degradation of chromosomal DNA may indicate that the toxicity of rubratoxin B is the consequence of apoptosis.
