Plasma pharmacokinetics of alkylresorcinol metabolites: new candidate biomarkers for whole-grain rye and wheat intake

• Published in: The American journal of clinical nutrition 2009-11, Vol.90 (5), p.1167-1171
• Main Authors: Söderholm, Päivi P, Koskela, Anja H, Lundin, Johan E, Tikkanen, Matti J, Adlercreutz, Herman C
• Format: Article
• Language: English
• Subjects: Adult; alkylresorcinols; Area Under Curve; Biological and medical sciences; Biomarkers; Biomarkers - blood; Biomarkers - metabolism; blood plasma; Body Mass Index; Body Weight; Catechols - blood; Catechols - metabolism; Catechols - pharmacokinetics; Chromatography, High Pressure Liquid; diet; diet-related diseases; Edible Grain; Energy Intake; epidemiological studies; etiology; Feeding. Feeding behavior; Female; food intake; functional foods; Fundamental and applied biological sciences. Psychology; gender differences; Grain; Humans; Male; mathematical models; men; Metabolism; Metabolites; pharmacokinetics; Pharmacology; phenolic compounds; Phenylpyruvic Acids - blood; Phenylpyruvic Acids - metabolism; Phenylpyruvic Acids - pharmacokinetics; Plasma; research methods; Resorcinols - blood; Resorcinols - metabolism; Resorcinols - pharmacokinetics; rye; special diets; Triticum; urine; Vertebrates: anatomy and physiology, studies on body, several organs or systems; Wheat; whole grain foods; women; Young Adult
• ISSN: 0002-9165; 1938-3207
• DOI: 10.3945/ajcn.2009.28290

BACKGROUND: Alkylresorcinols are phenolic compounds that are present almost exclusively in rye and wheat fiber. Alkylresorcinols are absorbed and thereafter metabolized to 3,5-dihydroxybenzoic acid (DHBA) and 3-(3,5-dihydroxyphenyl)-1-propanoic acid (DHPPA), which have been detected in human urine and plasma. OBJECTIVE: The objective was to determine the plasma pharmacokinetics of DHBA and DHPPA in human subjects to estimate whether they show potential as biomarkers for whole-grain rye and/or wheat intake. DESIGN: Fifteen human volunteers followed a low-alkylresorcinol diet for 2 d before ingesting a single dose of high-fiber rye bread containing 45 mg alkylresorcinols. Plasma samples were collected for 25 h, and the alkylresorcinol metabolites were quantified by HPLC with coulometric electrode array detection. RESULTS: Maximum concentrations were reached at [almost equal to]6 h for both metabolites, although interindividual variation was found. The half-life was significantly (P < 0.0002) longer for DHPPA (16.3 h) than for DHBA (10.1 h). No significant differences were discovered between women and men in the half-life of each metabolite, which, from a pharmacokinetic point of view, is the most important parameter. The area under the curve differed significantly between DHBA and DHPPA (P < 0.0001) and between women and men (P = 0.03 for DHBA and P = 0.01 for DHPPA). However, when corrected for body weight, the difference between sexes was no longer significant. CONCLUSIONS: Our results suggest that DHBA and DHPPA are both good candidate biomarkers for whole-grain rye and/or wheat intake; however, DHPPA is the better indicator because of its longer half-life. This could provide a practical tool when investigating the association between diet and diseases.