Natural compounds modulating human carbonic anhydrase activity and oxidative stress: a biochemical and molecular study

Abstract

In this study, the inhibitory effects of two natural compounds, hordenine and alpinetin, on human carbonic anhydrase isoforms hCA I and hCA II were investigated, together with their antioxidant properties. Carbonic anhydrase isoenzymes and oxidative stress are closely associated with metabolic, neurological, and inflammatory disorders, making multifunctional natural compounds attractive therapeutic candidates. Enzyme inhibition was evaluated using kinetic assays, and binding interactions were examined by molecular docking analyses. Antioxidant activities were determined through DMPD & centerdot;(+) radical scavenging and metal chelating assays. Hordenine showed moderate but significant inhibition, particularly against hCA II (IC50 = 54.09 & micro;M, Ki = 48.12 & micro;M), whereas alpinetin exhibited weaker inhibition toward both isoforms. Docking results were consistent with the experimental findings and provided supportive insights into the possible binding modes of the compounds, with hordenine displaying stronger binding affinities (- 8.31 and - 8.51 kcal/mol for hCA I and hCA II, respectively) through hydrogen bonding and hydrophobic interactions within the active site. In antioxidant assays, hordenine demonstrated superior metal chelating activity (IC50 = 11.08 & micro;g/mL), while alpinetin showed notable DMPD & centerdot;(+) radical scavenging capacity (IC50 = 23.05 & micro;g/mL). In conclusion, hordenine emerges as a promising natural scaffold for developing carbonic anhydrase inhibitors with additional antioxidant properties, whereas alpinetin provides complementary radical scavenging activity.