Inhibition of Mammalian Carbonic Anhydrase Isoforms I, II and VI with Thiamine and Thiamine-Like Molecules

Abstract

Here we determined the in vitro inhibitory effects of 5-(2-hydroxyethyl)-3,4-dimethylthiazolium iodide (1), 3-Benzyl-5-(2-hydroxyethyl)-4-methylthiazolium chloride (2) and thiamine (3) on human erythrocyte carbonic anhydrase I, II isozymes (hCA i and hCA II) and secreted isoenzyme CA Vi. K<inf>i</inf> values ranged from 0.38 to 2.27 μM for hCA I, 0.085 to 0.784 μM for hCA II and 0.062 to 0.593 μM for hCA VI, respectively. The compounds displayed relatively strong actions on hCA II, in the same range as the clinically used sulfonamidesethoxzolamide, zonisamide and acetazolamide. © 2013 informa UK, Ltd.