title: Interaction of aspirin and vitamin C with bovine serum albumin.
abstract: Vitamin C (L-ascorbic acid) has a major biological role as a natural antioxidant. Aspirin belongs to the nonsteroidal anti-inflammatory drugs and functions as an antioxidant via its ability to scavenge-OH radicals. Bovine serum albumin (BSA) is the major soluble protein constituent of the circulatory system and has many physiological functions including transport of a variety of compounds. In this report, the competitive binding of vitamin C and aspirin to bovine serum albumin has been studied using constant protein concentration and various drug concentrations at pH 7.2. FTIR and UV-Vis spectroscopic methods were used to analyze vitamin C and aspirin binding modes, the binding constants and the effects of drug complexation on BSA stability and conformation. Spectroscopic evidence showed that vitamin C and aspirin bind BSA via hydrophilic interactions (polypeptide and amine polar groups) with overall binding constants of K(vitamin C-BSA)=1.57×10(4)M(-1) and K(aspirin-BSA)=1.15×10(4)M(-1); assuming that there is one drug molecule per protein. The BSA secondary structure was altered with major decrease of α-helix from 64% (free protein) to 57% (BSA-vitamin C) and 54% (BSA-aspirin) and β-sheet from 15% (free protein) to 6-7% upon drug complexation, inducing a partial protein destabilization.
authors: Department of Chemistry, Islamic Azad University, Central Tehran Branch, Tehran, Iran. drsnafisi@yahoo.com
authors: Shohreh
authors: S
authors: Nafisi
authors: Golshan
authors: G
authors: Bagheri Sadeghi
authors: Ataollah
authors: A
authors: PanahYab
mesh_terms: D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000378:metabolism* / Q000494:pharmacology; D000975:Antioxidants / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D001205:Ascorbic Acid / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D001241:Aspirin / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D002417:Cattle; D004305:Dose-Response Relationship, Drug; D011485:Protein Binding; D011487:Protein Conformation / Q000187:drug effects; D055550:Protein Stability / Q000187:drug effects; D012710:Serum Albumin, Bovine / Q000737:chemistry / Q000378:metabolism*; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D000975:Antioxidants; D012710:Serum Albumin, Bovine; D001205:Ascorbic Acid; D001241:Aspirin