title: Effects of Cassia obtusifolia (sicklepod) extracts and anthraquinones on muscle mitochondrial function.
abstract: Naturally occurring quinones and quinone-containing extracts of seeds of the toxic plant Cassia obtusifolia (sicklepod) affected muscle mitochondrial function. Aqueous suspensions and organic extracts of C. obtusifolia seeds slightly elevated plasma creatine kinase levels of Sprague-Dawley rats. These extracts were analyzed by fused silica capillary gas chromatography and found to contain nine anthraquinones and three anthrones. Urinary metabolites primarily consisted of beta-glucuronide conjugates of the anthraquinones. The three anthrones or conjugate analogues were not present in the urine in detectable amounts. Emodin, doxorubicin and organic extracts of C. obtusifolia inhibited NADH:cytochrome c oxidoreductase activity of bovine heart mitochondrial particles and NADH:CoQ oxidoreductase activity of porcine heart mitochondrial NADH dehydrogenase, whereas juglone was stimulatory. Relative quinone metabolism correlated with semiquinone formation rate and with redox potential. A protective effect of coenzyme Q against enzyme inhibition by anthraquinones was also observed.
authors.affiliation: Department of Environmental Toxicology, University of California, Davis 95616.
authors.forename: D C
authors.initials: DC
authors.lastname: Lewis
authors.forename: T
authors.initials: T
authors.lastname: Shibamoto
mesh_terms: D000818:Animals; D000880:Anthraquinones / Q000494:pharmacology* / Q000652:urine; D001835:Body Weight / Q000187:drug effects; D002366:Cassia; D002849:Chromatography, Gas; D003579:Cytochrome Reductases / Q000378:metabolism; D066298:In Vitro Techniques; D008297:Male; D008931:Mitochondria, Muscle / Q000187:drug effects* / Q000201:enzymology; D010936:Plant Extracts / Q000633:toxicity*; D010946:Plants, Medicinal; D051381:Rats; D011919:Rats, Inbred Strains; D014969:Xanthine Oxidase / Q000378:metabolism
chemical_list: D000880:Anthraquinones; D010936:Plant Extracts; D014969:Xanthine Oxidase; D003579:Cytochrome Reductases