title: A simple and sensitive method for the determination of fibric acids in the liver by liquid chromatography.
abstract: Fibrates are used in biochemical and pharmacological studies as bioactive tools. Nevertheless, most studies have lacked information concerning the concentrations of fibric acids working inside tissues because a simple and sensitive method is not available for their quantitation. This study aimed to develop a simple and sensitive bioanalytical method for the quantitation of clofibric, bezafibric and fenofibric acids in samples of very small portions of tissues. Fibric acids were extracted into n-hexane-ethyl acetate from tissue homogenates (10 mg of liver, kidney or muscle) or serum (100 µL) and were derivatized with 4-bromomethyl-6,7-dimethoxycoumarin, followed by HPLC with fluorescence detection. These compounds were separated isocratically on a reversed phase with acetonitrile-water. Standard analytical curves were linear over the concentration range of 0.2-20 nmol/10 mg of liver. Precision and accuracy were within acceptable limits. Recovery from liver homogenates ranged from 93.03 to 112.29%. This method enabled the quantitation of fibric acids in 10 mg of liver from rats treated with clofibric acid, bezafibric acid or fenofibrate. From these analytical data, it became clear that there was no large difference in ratio of acyl-CoA oxidase 1 (Acox1) mRNA level to fibric acid content in the liver among the three fibric acids, suggesting that these three fibric acids have similar potency to increase expression of the Acox1 gene, which is a target of peroxisome proliferator-activated receptor α. Thus, the proposed method is a simple, sensitive and reliable tool for the quantitation of fibric acids working in vivo inside livers.
authors.affiliation: Faculty of Pharmaceutical Sciences, Josai University.
authors.forename: Minako
authors.initials: M
authors.lastname: Karahashi
authors.forename: Hiroto
authors.initials: H
authors.lastname: Fukuhara
authors.forename: Miki
authors.initials: M
authors.lastname: Hoshina
authors.forename: Takeshi
authors.initials: T
authors.lastname: Sakamoto
authors.forename: Tohru
authors.initials: T
authors.lastname: Yamazaki
authors.forename: Atsushi
authors.initials: A
authors.lastname: Mitsumoto
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Kawashima
authors.forename: Naomi
authors.initials: N
authors.lastname: Kudo
mesh_terms: D042962:Acyl-CoA Oxidase / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D001629:Bezafibrate / Q000378:metabolism* / Q000494:pharmacology; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D002995:Clofibric Acid / Q000378:metabolism* / Q000493:pharmacokinetics / Q000494:pharmacology; D011345:Fenofibrate / Q000031:analogs & derivatives* / Q000378:metabolism / Q000493:pharmacokinetics / Q000494:pharmacology; D058607:Fibric Acids / Q000378:metabolism* / Q000493:pharmacokinetics / Q000494:pharmacology; D008099:Liver / Q000378:metabolism*; D008297:Male; D047493:PPAR alpha / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D015203:Reproducibility of Results
chemical_list: D058607:Fibric Acids; D047493:PPAR alpha; D012333:RNA, Messenger; D002995:Clofibric Acid; C010285:fibric acid; C006012:fenofibric acid; D042962:Acyl-CoA Oxidase; D011345:Fenofibrate; D001629:Bezafibrate