title: beta-Carotene effectively scavenges toxic nitrogen oxides: nitrogen dioxide and peroxynitrous acid.
abstract: beta-Carotene absorbed 2 equimolar amounts of NO2 accompanying the complete destruction of beta-carotene. Electron spin resonance study using 2-phenyl-4,4,5,5-tetramethylimidazoline-3-oxide-1-oxyl revealed that no significant amounts of NO were released by the interaction. Nitrogen atoms derived from NO2 were tightly bound to the beta-carotene molecules. Destruction of beta-carotene was inhibited little by alpha-tocopherol and polyunsaturated fatty esters, and slightly by ascorbyl palmitate, indicating that beta-carotene was a more effective scavenger of NO2. ONOOH/ONOO- and 3-morpholinosydononimine similarly destroyed beta-carotene. The results suggest that beta-carotene contributes to the prevention of cytotoxicity and genotoxicity of NO2 and ONOOH/ONOO- derived from NO.
authors.affiliation: School of Pharmacy, Tokyo University of Pharmacy and Life Science, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Kikugawa
authors.forename: K
authors.initials: K
authors.lastname: Hiramoto
authors.forename: S
authors.initials: S
authors.lastname: Tomiyama
authors.forename: Y
authors.initials: Y
authors.lastname: Asano
mesh_terms: D000584:Amiloride / Q000031:analogs & derivatives / Q000737:chemistry; D001205:Ascorbic Acid / Q000031:analogs & derivatives / Q000737:chemistry; D004281:Docosahexaenoic Acids / Q000737:chemistry; D004578:Electron Spin Resonance Spectroscopy; D016166:Free Radical Scavengers / Q000737:chemistry*; D009566:Nitrates / Q000737:chemistry*; D009585:Nitrogen Dioxide / Q000737:chemistry*; D014810:Vitamin E / Q000737:chemistry; D019207:beta Carotene / Q000737:chemistry*
chemical_list: D016166:Free Radical Scavengers; D009566:Nitrates; D019207:beta Carotene; D014810:Vitamin E; D004281:Docosahexaenoic Acids; C039642:peroxynitric acid; D000584:Amiloride; C067518:4,7,10,13,16,19-docosahexaenoic acid ethyl ester; D001205:Ascorbic Acid; C031226:6-O-palmitoylascorbic acid; D009585:Nitrogen Dioxide; C039614:ethylisopropylamiloride