title: Simple measurement of gluconeogenesis by direct 2H NMR analysis of menthol glucuronide enrichment from 2H2O.
abstract: The contribution of gluconeogenesis to fasting glucose production was determined by a simple measurement of urinary menthol glucuronide (MG) 2H enrichment from 2H2O. Following ingestion of 2H2O (0.5% body water) during an overnight fast and a pharmacological dose (400 mg) of a commercial peppermint oil preparation the next morning, 364 micromol MG was quantitatively recovered from a 2-h urine collection by ether extraction and a 125 micromol portion was directly analyzed by 2H NMR. The glucuronide 2H-signals were fully resolved and their relative intensities matched those of the monoacetone glucose derivative. The pharmacokinetics and yields of urinary MG after ingestion of 400 mg peppermint oil as either gelatin or enteric-coated capsules 1 h before breakfast were quantified in five healthy subjects. Gelatin capsules yielded 197 +/- 81 micromol of MG from the initial 2-h urine collection while enteric-coated capsules gave 238 +/- 84 micromol MG from the 2- to 4-h urine collection.
authors: Department of Chemistry, University of Coimbra, Coimbra, Portugal.
authors: Angela
authors: A
authors: Ribeiro
authors: M Madalena
authors: MM
authors: Caldeira
authors: Manuela
authors: M
authors: Carvalheiro
authors: Margarida
authors: M
authors: Bastos
authors: Carla
authors: C
authors: Baptista
authors: Ana
authors: A
authors: Fagulha
authors: Luisa
authors: L
authors: Barros
authors: Cristina
authors: C
authors: Barosa
authors: John G
authors: JG
authors: Jones
mesh_terms: D000328:Adult; D003903:Deuterium; D005260:Female; D005943:Gluconeogenesis; D005965:Glucuronates / Q000652:urine*; D006801:Humans; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008297:Male; D036142:Mentha piperita; D008610:Menthol / Q000031:analogs & derivatives* / Q000652:urine; D010938:Plant Oils / Q000008:administration & dosage / Q000494:pharmacology*
chemical_list: D005965:Glucuronates; D010938:Plant Oils; D008610:Menthol; C044963:menthol glucuronide; D003903:Deuterium; C015424:peppermint oil