title: Study on the metabolic mechanism of chiral inversion of S-mandelic acid in vitro.
abstract: Mandelic acid (MA) is generally used as a biological indicator of occupational exposure to styrene, which is classified as a class of hazardous environmental pollutants. It was found to undergo one-directional chiral inversion (S-MA to R-MA) in Wistar and Sprague-Dawley rats in vivo. This study was aimed to explore the metabolic mechanism of chiral inversion of S-MA in vitro. S-MA was converted to R-MA in rat hepatocytes, whereas MA enantiomers remained unchanged in acidic and neutral phosphate buffers, HepG2 cells, and intestinal flora. In addition, the synthesized S-MA-CoA thioester was rapidly racemized and hydrolyzed to R-MA by rat liver homogenate and S9, cytosolic and mitochondrial fractions. The data suggest that chiral inversion of S-MA may involve the hydrolysis of S-MA-CoA, and its metabolic mechanism could be the same as that of 2-arylpropionic acid (2-APA) drugs.
authors.affiliation: Department of Pharmaceutical Analysis and Drug Metabolism, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China.
authors.forename: Ling-Bo
authors.initials: LB
authors.lastname: Gao
authors.forename: Jin-Zhao
authors.initials: JZ
authors.lastname: Wang
authors.forename: Tong-Wei
authors.initials: TW
authors.lastname: Yao
authors.forename: Su
authors.initials: S
authors.lastname: Zeng
mesh_terms: D000818:Animals; D002460:Cell Line; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D066298:In Vitro Techniques; D008099:Liver / Q000378:metabolism; D008333:Mandelic Acids / Q000737:chemistry / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D017208:Rats, Wistar; D013237:Stereoisomerism; D013347:Subcellular Fractions / Q000378:metabolism
chemical_list: D008333:Mandelic Acids; C037938:mandelic acid