title: Cytotoxicity of lawsone and cytoprotective activity of antioxidants in catalase mutant Escherichia coli.
abstract: Lawsone is an active naphthoquinone derivative isolated from henna (Lawsonia inermis L.), a widely used hair dye. Previous study on the toxicity of lawsone remains unclear since the involvement of oxidative stress and the kind of ROS (reactive oxygen species) involved have not been fully resolved yet. This present study reports the cytotoxic effects of lawsone and henna. We carried out CAT assay (a zone of inhibition test of bacterial growth and colony-forming efficiency test of transformant Escherichia coli strains that express mammalian catalase gene derived from normal catalase mice (Cs(a)) and catalase-deficient mutant mice (Cs(b))), Ames mutagenicity assay and H(2)O(2) generation assay. Lawsone generated H(2)O(2) slightly in phosphate buffer system and was not mutagenic in Ames assay using TA 98, TA 100 and TA 102, both in the absence and presence of metabolic activation. Lawsone exposure inhibited the growth of both Cs(a) and Cs(b) strains in a dose-dependent manner. Mean zone diameter for Cs(a) was 9.75+/-0.96 mm and 12.75+/-1.5 mm for Cs(b). Natural henna leaves did not show toxic effects, whereas two out of four samples of marketed henna products were shown toxicity effects. Catalase abolished zone of inhibition (ZOI) of marketed henna products, eliminated ZOI of lawsone in a dose-dependent manner and low concentration of exogenous MnSOD and Cu/ZnSOD eliminated the toxicity. Histidine and DTPA, the metal chelator; BHA and low concentration of capsaicin, the inducer of NADH-quinone reductase, effectively protected Cs(a) and Cs(b) against lawsone in this study. We suggest that lawsone cytotoxicity is probably mediated, at least in part, by the release of O(2)(-), H(2)O(2) and OH(-).
authors: Department of Public Health, Okayama University, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Okayama 700-8558, Japan.
authors: Rani
authors: R
authors: Sauriasari
authors: Da-Hong
authors: DH
authors: Wang
authors: Yoko
authors: Y
authors: Takemura
authors: Ken
authors: K
authors: Tsutsui
authors: Noriyoshi
authors: N
authors: Masuoka
authors: Kuniaki
authors: K
authors: Sano
authors: Masako
authors: M
authors: Horita
authors: Bing-Ling
authors: BL
authors: Wang
authors: Keiki
authors: K
authors: Ogino
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism / Q000494:pharmacology*; D001205:Ascorbic Acid / Q000494:pharmacology; D002083:Butylated Hydroxyanisole / Q000494:pharmacology; D002211:Capsaicin / Q000494:pharmacology; D002374:Catalase / Q000235:genetics / Q000378:metabolism*; D019610:Cytoprotection / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D004926:Escherichia coli / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics / Q000254:growth & development; D006202:Hair Dyes / Q000302:isolation & purification / Q000633:toxicity*; D006639:Histidine / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000378:metabolism; D017665:Hydroxyl Radical / Q000378:metabolism; D031564:Lawsonia Plant / Q000737:chemistry; D051379:Mice; D008826:Microbial Sensitivity Tests; D009154:Mutation; D009285:Naphthoquinones / Q000302:isolation & purification / Q000633:toxicity*; D018384:Oxidative Stress / Q000187:drug effects; D004369:Pentetic Acid / Q000494:pharmacology; D010936:Plant Extracts / Q000633:toxicity; D017382:Reactive Oxygen Species / Q000378:metabolism*; D013482:Superoxide Dismutase / Q000378:metabolism; D013481:Superoxides / Q000378:metabolism
chemical_list: D000975:Antioxidants; D006202:Hair Dyes; D009285:Naphthoquinones; D010936:Plant Extracts; D017382:Reactive Oxygen Species; D013481:Superoxides; D002083:Butylated Hydroxyanisole; D017665:Hydroxyl Radical; D006639:Histidine; D004369:Pentetic Acid; D006861:Hydrogen Peroxide; D002374:Catalase; D013482:Superoxide Dismutase; D001205:Ascorbic Acid; D002211:Capsaicin; C005090:lawsone