Spectroscopic investigations of the interaction of the anti-hypertension drug valsartan with human serum albumin

Abstract

The aim of the present study was to investigate the interaction between valsartan, an anti-hypertension drug, and human serum albumin (HSA) using spectroscopic techniques, including fluorescence, ultraviolet-visible absorption, synchronous fluorescence and circular dichroism (CD). The results demonstrated that valsartan and HSA form a complex and that a static quenching mechanism occurs. In addition, the binding constant and the number of binding sites for valsartan on HSA were analyzed. Hydrophobic interactions and hydrogen bonds were the predominant forces in the association reaction based on thermodynamic parameters. The distance between the donor (HSA) and the acceptor (valsartan) was 1.994 nm as derived from Forster's theory. Alterations in the secondary structure of HSA in the presence of valsartan were assessed using synchronous fluorescence and CD. This study provides an enhanced understanding of the pharmacodynamic effects of valsartan on the physiologically important protein HSA.

Inhibitory Mechanism of Taxifolin against α-Glucosidase Based on Spectrofluorimetry and Molecular Docking

“…Table 3. The negative ΔG indicated that the formation of complex of taxifolin and αglucosidase was spontaneous while the negative ΔH and ΔS suggested that the conformation of the complex was maintained by van der Waals and hydrogen bonds according to the previous studies [16,17]. The molecular docking method is widely used to study the binding modes of enzymes and inhibitors.…”

Interaction mechanism of aloe-emodin with trypsin: molecular structure–affinity relationship and effect on biological activities

“…The interaction between the emission peak of trypsin and AE showed a red shi of 1 nm (from 277 nm to 278 nm), which indicated that hydrophobicity decreased and polarity increased in the Trp microenvironment due to AE insertion. 25 In addition, with the increase of AE concentration, the uorescence intensity at Dl ¼ 60 nm decreased steadily, which supported the uorescence quenching when AE interacts with trypsin. For Tyr residue with Dl ¼ 15 nm, the emission peak decreased with the increase of AE concentration, but the maximum emission wavelength did not change signicantly, indicating that the microenvironment around Tyr residue was less disturbed.…”

A Cole‐Cole Dielectric Relaxation Analysis of Albumin and γ‐Globulins for Protein Quantification by Electrical Impedance Spectroscopy

“…Other than albumin and globulin, body fluids such as serum are also rich in mineral ions hence the need for experimental cases E and F which elucidated additional synergism due to presence of the mineral ions. At normal body pH, albumin in serum binds cations such as sodium, copper and zinc as well as other exogenous ligands like drugs which synergistically alter the dielectric properties of serum. The strong binding is supported by improved hyponatremia following albumin infusion .…”

“…Serum albumin contains 585 amino acids which includes a single tryptophan Trp‐214 residue in its hydrophobic cavity among other large aromatic amino acids like tyrosine (Figure c), and phenyl alanine . When albumin is subjected to electric current, re‐orientation of its amino acids occurs.…”