title: Characterization of [6]-gingerol metabolism in rat by liquid chromatography electrospray tandem mass spectrometry.
abstract: [6]-Gingerol is a structural analog of capsaicin, an agonist of the transient receptor potential channel vanilloid 1, which is known to have therapeutic properties for the treatment of pain and inflammation. A selective and sensitive quantitative method for the determination of [6]-gingerol by HPLC-ESI/MS/MS was developed. The method consisted of a protein precipitation extraction followed by analysis using liquid chromatography electrospray tandem mass spectrometry. The chromatographic separation was achieved using a Thermo 100 × 2.1 mm C(8) column combined with an isocratic mobile phase composed of acetonitrile, water and formic acid (80:20:0.1) at a flow rate of 250 μL/min. The mass spectrometer was operating in SRM mode and an analytical range set at 20-5000 ng/mL was used to construct a calibration curve in rat plasma. The interbatch precision (%CV) and accuracy (%NOM) observed were 2.9-10.8% and 98.1-102.1% in rat plasma. Similarly, precision and accuracy in rat liver microsomal suspension were also evaluated at nominal concentrations of 1, 25 and 100 μm; the precision (%CV) was <3.4% and the accuracy (%NOM) observed ranged from 89.7 to 109.4%. An in vitro metabolic stability study using rat liver microsomes was performed to determine intrinsic clearance of [6]-gingerol. The results show slow degradation with a T(1/2) of 163 min and relatively low intrinsic clearance suggesting that phase I metabolism may not be a major contributor of the drug clearance. Further analyses were performed to characterize in vitro and in vivo metabolites. Three main phase I metabolites and four phase II metabolites were identified by HPLC-MS/MS and HPLC-MSD TOF. However, the results suggest that glucuronidation of hydroxylated [6]-gingerol is the primary metabolite excreted in rat urine.
authors.affiliation: Département de biomédecine vétérinaire, Faculté de médecine vétérinaire, Université de Montréal, Québec, Canada.
authors.forename: Marie-Lou
authors.initials: ML
authors.lastname: Gauthier
authors.forename: Jennifer
authors.initials: J
authors.lastname: Douat
authors.forename: Pascal
authors.initials: P
authors.lastname: Vachon
authors.forename: Francis
authors.initials: F
authors.lastname: Beaudry
mesh_terms: D000818:Animals; D002138:Calibration; D002211:Capsaicin / Q000032:analysis / Q000737:chemistry / Q000493:pharmacokinetics; D002396:Catechols / Q000032:analysis / Q000737:chemistry* / Q000493:pharmacokinetics*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004285:Dogs; D005233:Fatty Alcohols / Q000032:analysis / Q000737:chemistry* / Q000493:pharmacokinetics*; D006801:Humans; D007700:Kinetics; D008297:Male; D008862:Microsomes, Liver / Q000378:metabolism; D017711:Nonlinear Dynamics; D051381:Rats; D017207:Rats, Sprague-Dawley; D012680:Sensitivity and Specificity; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D002396:Catechols; D005233:Fatty Alcohols; C007845:gingerol; D002211:Capsaicin