title: Effects of kava alkaloid, pipermethystine, and kavalactones on oxidative stress and cytochrome P450 in F-344 rats.
abstract: Kava-containing products remain popular in the United States and continue to be sold in health food stores and ethnic markets regardless of the fact that it was banned in Western countries such as Germany, France, Switzerland, Australia, and Canada, following reports of alleged hepatotoxicity. It is therefore critical to establish efficacy and verify adverse effects and/or herb-drug interactions for kava-kava (Piper methysticum). We have previously demonstrated that kava alkaloid, pipermethystine (PM), abundant in leaves and stem peelings, induces mitochondrial toxicity in human hepatoma cells, HepG2, as compared with the bioactive components, kavalactones (KL), abundant in the rhizome. The current study compared short-term toxic effects of PM in Fischer-344 (F-344) rats to acetone-water extracts of kava rhizome (KRE). Treatment of F-344 rats with PM (10 mg/kg) and KRE (100 mg/kg) for 2 weeks failed to elicit any significant changes in liver function tests or cause severe hepatic toxicity as measured by lipid peroxidation and apoptosis markers such as malondialdehyde, Bax, and Bcl-2. However, PM-treated rats demonstrated a significant increase in hepatic glutathione, cytosolic superoxide dismutase (Cu/ZnSOD), tumor necrosis factor alpha mRNA expression, and cytochrome P450 (CYP) 2E1 and 1A2, suggesting adaptation to oxidative stress and possible drug-drug interactions.
authors.affiliation: Laboratory of Metabolic Disorders and Alternative Medicine, Department of Molecular Biosciences and Bioengineering, University of Hawaii at Manoa, Honolulu, Hawaii 96822, USA.
authors.forename: Steven T S
authors.initials: ST
authors.lastname: Lim
authors.forename: Klaus
authors.initials: K
authors.lastname: Dragull
authors.forename: Chung-Shih
authors.initials: CS
authors.lastname: Tang
authors.forename: Harry C
authors.initials: HC
authors.lastname: Bittenbender
authors.forename: Jimmy T
authors.initials: JT
authors.lastname: Efird
authors.forename: Pratibha V
authors.initials: PV
authors.lastname: Nerurkar
mesh_terms: D000470:Alkaloids / Q000302:isolation & purification / Q000633:toxicity*; D000818:Animals; D019388:Cytochrome P-450 CYP1A2 / Q000096:biosynthesis; D019389:Cytochrome P-450 CYP2D6 / Q000096:biosynthesis; D019392:Cytochrome P-450 CYP2E1 / Q000096:biosynthesis; D003577:Cytochrome P-450 Enzyme System / Q000096:biosynthesis*; D003580:Cytochromes; D004790:Enzyme Induction / Q000187:drug effects; D005978:Glutathione / Q000235:genetics / Q000378:metabolism; D020901:Kava; D007783:Lactones / Q000302:isolation & purification / Q000633:toxicity*; D008099:Liver / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism*; D008297:Male; D008930:Mitochondria, Liver / Q000187:drug effects / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects*; D010936:Plant Extracts / Q000737:chemistry / Q000633:toxicity; D018515:Plant Leaves; D011728:Pyridones / Q000302:isolation & purification / Q000633:toxicity*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D011916:Rats, Inbred F344; D017382:Reactive Oxygen Species / Q000378:metabolism; D027343:Rhizome; D013482:Superoxide Dismutase / Q000235:genetics / Q000378:metabolism; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000378:metabolism; D015854:Up-Regulation
chemical_list: D000470:Alkaloids; D003580:Cytochromes; D007783:Lactones; D010936:Plant Extracts; D011728:Pyridones; D012333:RNA, Messenger; D017382:Reactive Oxygen Species; D014409:Tumor Necrosis Factor-alpha; C448623:pipermethystine; D003577:Cytochrome P-450 Enzyme System; D019392:Cytochrome P-450 CYP2E1; C017170:Cyp1a2 protein, rat; D019388:Cytochrome P-450 CYP1A2; D019389:Cytochrome P-450 CYP2D6; D013482:Superoxide Dismutase; D005978:Glutathione