Study on the interaction of Olmesartan with human serum albumin (HSA) by spectroscopic and molecular docking techniques
نویسندگان
1 Department of Chemistry, Faculty of Science, Imam Khomeini International University, Qazvin, Iran
2 Department of Chemistry, Qa.C., Islamic Azad University, Qazvin, Iran
3 Department of Chemistry, Faculty of Science, Imam Khomeini International University, Qazvin, Iran
doi
10.22034/crl.2025.494168.1492چکیده
This study aims to investigate the interaction of olmesartan drug with human serum albumin (HSA) using fluorescence, circular dichroism (CD) spectra and molecular docking techniques under physiological conditions. Fluorescence quenching of HSA by olmesartan indicated that a moderate binding affinity (Ka = 3305 M‒1) and spontaneous reaction between olmesartan and HSA obtained in phosphate buffer (0.05 M) and pH 7.4 at 25° C. The CD results revealed a decrease in the α-helical content of HSA from 61.1% to 59.2% with the addition of olmesartan, indicating that olmesartan binding induces changes in the secondary structure of HSA. The study of molecular docking also indicated that the optimal binding site for olmesartan on HSA is located in the IIA and IIB subdomains. Thermodynamic analysis and molecular docking results suggested that the binding of olmesartan to HSA is dominated by hydrophobic interactions and hydrogen bonds. Also, olmesartan formed hydrophobic interactions with Trp214, Asp451, Tyr452, and Asn295, and established five hydrogen bonds with Lys195, Arg218, and Pro339. However, theoretical and experimental findings demonstrated excellent agreement.
