Evaluation of some thiophene-based sulfonamides as potent inhibitors of carbonic anhydrase I and II isoenzymes isolated from human erythrocytes by kinetic and molecular modelling studies

• Published in: Pharmacological reports Vol. 72; no. 6; pp. 1738 - 1748
• Main Authors: Alım, Zuhal, Köksal, Zeynep, Karaman, Muhammet
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.12.2020
• Subjects: Drug Safety and Pharmacovigilance; Medicine; Pharmacotherapy; Pharmacy; Sulfonamide; Molecular modelling; Thiophene; Inhibition; Carbonic anhydrase
• DOI: 10.1007/s43440-020-00149-4
• ISSN: 1734-1140

Background Thiophene(s) are an important group in therapeutic applications, and sulfonamides are the most important class of carbonic anhydrase (CA) inhibitors. In this study, inhibition effects of some thiophene-based sulfonamides on human erythrocytes carbonic anhydrase I and II isoenzymes (hCA-I and hCA-II) were investigated. Thiophene-based sulfonamides used in this study showed potent inhibition effect on both isoenzymes at very small concentrations. Materials and methods We report on the purification of the carbonic anhydrase I and II isoenzymes (hCA-I and hCA-II) using affinity chromatography method. The inhibition effect of the thiophene-based sulfonamides was determined by IC 50 and K i parameters. A molecular docking study was performed for each molecule. Results Thiophene-based sulfonamides showed IC 50 values of in the range of 69 nM to 70 µM against hCA-I, 23.4 nM to 1.405 µM against hCA-II. K i values were in the range of 66.49 ± 17.15 nM to 234.99 ± 15.44 µM against hCA-I, 74.88 ± 20.65 nM to 38.04 ± 12.97 µM against hCA-II. Thiophene-based sulfonamides studied in this research showed noncompetitive inhibitory properties on both isoenzymes. To elucidate the mechanism of inhibition, a molecular docking study was performed for molecules 1 and 4 exhibiting a strong inhibitory effect on hCA-I and hCA-II. The compounds inhibit the enzymes by interacting out of catalytic active site. The sulfonamide and thiophene moiety played a significant role in the inhibition of the enzymes. Conclusion We hope that this study will contribute to the design of novel thiophene-based sulfonamide derived therapeutic agents that may be carbonic anhydrase inhibitors in inhibitor design studies.