title: Carbonic anhydrase inhibitors: in vitro inhibition of α isoforms (hCA I, hCA II, bCA III, hCA IV) by flavonoids.
abstract: A series of flavonoids, such as quercetin, catechin, apigenin, luteolin, morin, were investigated for their inhibitory effects against the metalloenzyme carbonic anhydrase (CA). The compounds were tested against four α-CA isozymes purified from human and bovine (hCA I, hCA II, bCA III, hCA IV) tissues. The four isozymes showed quite diverse inhibition profiles with these compounds. The flavonoids inhibited hCA I with K(I)-s in the range of 2.2-12.8 μM, hCA II with K(I)-s in the range of 0.74-6.2 μM, bCA III with K(I)-s in the range of 2.2-21.3 μM, and hCA IV with inhibition constants in the range of 4.4-15.7, with an esterase assay using 4-nitrophenyl acetate as substrate. Some simple phenols/sulfonamides were also investigated as standard inhibitors. The flavonoids incorporate phenol moieties which inhibit these CAs through a diverse, not yet determined inhibition mechanism, compared to classic inhibitors such as the sulfonamide/sulfamate ones.
authors.affiliation: Department of Agricultural Biotechnology, Ondokuz Mayis University, Faculty of Agriculture, Samsun, Turkey.
authors.forename: Derya
authors.initials: D
authors.lastname: Ekinci
authors.forename: Lutfi
authors.initials: L
authors.lastname: Karagoz
authors.forename: Deniz
authors.initials: D
authors.lastname: Ekinci
authors.forename: Murat
authors.initials: M
authors.lastname: Senturk
authors.forename: Claudiu T
authors.initials: CT
authors.lastname: Supuran
mesh_terms: D002257:Carbonic Anhydrase Inhibitors / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D002256:Carbonic Anhydrases / Q000302:isolation & purification / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D005419:Flavonoids / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D006801:Humans; D015394:Molecular Structure; D020033:Protein Isoforms / Q000037:antagonists & inhibitors / Q000302:isolation & purification / Q000378:metabolism; D013329:Structure-Activity Relationship
chemical_list: D002257:Carbonic Anhydrase Inhibitors; D005419:Flavonoids; D020033:Protein Isoforms; D002256:Carbonic Anhydrases