Alkaloid From Kava Leaves, Stems Hepatotoxic

<<< Back to main page

Kava Kava has been reported to be responsible for liver failure and death in human subjects. This report suggests why. From Natural Products Insider
Posted on: 02/16/2004

HONOLULU--A new study reported that kava's reported hepatoxicity may be caused by a compound found in the herb's stems and leaves. Pipermethystine (PM), a major alkaloid found in the stems and leaves of the kava plant, may adversely affect human hepatoma cells, according to researchers at the University of Hawaii at Manoa; the study will be published in a future issue of Toxicological Sciences; ( toxsci.oupjournal.org).

Researchers found 100 micro M of PM administered to human hepatoma cells (HepG2) caused a 90-percent loss in cell viability within 24 hours, while exposure of 50 micro M caused cell death in approximately 65 percent of cells. In comparison, similar concentrations of kavalactones (7, 8-dihydromethysticin, DHM; and desmethoxyyangonin, DMY) did not affect cell viability up to eight days of treatment, according to the study.

"Mechanistic studies indicate that in contrast to kavalactones, PM significantly decreased cellular ATP levels, mitochondrial membrane potential and induced apoptosis . after 24 hours of treatment," wrote the researchers, who concluded PM is capable of causing cell death by possibly disrupting mitochondrial function, while kavalactones do not.

"This has to be replicated in animal studies to see if it really works," said Mark Blumenthal, president of the American Botanical Council (ABC), "and it doesn't really apply to the marketplace because [the study] is not dealing with kava root."

Back to top of document