title: Inhibition of topoisomerases by fatty acids.
abstract: The inhibitory effects of various fatty acids on topoisomerases were examined, and their structure activity relationships and mechanism of action were studied. Saturated fatty acids (C6:0 to C22:0) did not inhibit topoisomerase I, but cis-unsaturated fatty acids (C16:1 to C22:1) with one double bond showed strong inhibition of the enzyme. The inhibitory potency depended on the carbon chain length and the position of the double bond in the fatty acid molecule. The trans-isomer, methyl ester and hydroxyl derivative of oleic acid had no or little inhibitory effect on topoisomerases I and II. Among the compounds studied petroselinic acid and vaccenic acid (C18:1) with a cis-double bond were the potent inhibitors. Petroselinic acid was a topoisomerase inhibitor of the cleavable complex-nonforming type and acted directly on the enzyme molecule in a noncompetitive manner without DNA intercalation.
authors.affiliation: Faculty of Pharmaceutical Sciences, Kumamoto University, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Suzuki
authors.forename: F
authors.initials: F
authors.lastname: Shono
authors.forename: H
authors.initials: H
authors.lastname: Kai
authors.forename: T
authors.initials: T
authors.lastname: Uno
authors.forename: M
authors.initials: M
authors.lastname: Uyeda
mesh_terms: D000818:Animals; D000951:Antigens, Neoplasm; D002417:Cattle; D004264:DNA Topoisomerases, Type I / Q000378:metabolism; D004250:DNA Topoisomerases, Type II / Q000378:metabolism; D004268:DNA-Binding Proteins; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D005227:Fatty Acids / Q000494:pharmacology*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007527:Isoenzymes / Q000037:antagonists & inhibitors* / Q000378:metabolism; D007700:Kinetics; D010920:Placenta / Q000201:enzymology; D013329:Structure-Activity Relationship; D013950:Thymus Gland / Q000201:enzymology; D059004:Topoisomerase I Inhibitors; D059005:Topoisomerase II Inhibitors
chemical_list: D000951:Antigens, Neoplasm; D004268:DNA-Binding Proteins; D004791:Enzyme Inhibitors; D005227:Fatty Acids; D007527:Isoenzymes; D059004:Topoisomerase I Inhibitors; D059005:Topoisomerase II Inhibitors; D004264:DNA Topoisomerases, Type I; D004250:DNA Topoisomerases, Type II