title: Serum beta-glucuronidase activity is inversely associated with plant-food intakes in humans.
abstract: Beta-glucuronidase hydrolyzes glucuronide moieties from steroids and xenobiotics, such that circulating glucuronyl conjugates can interact with target tissues. In animal models, dietary constituents can alter beta-glucuronidase activity. In humans, serum beta-glucuronidase activity reflects liver enzyme loss during cell turnover, and thus is a surrogate for hepatic beta-glucuronidase. We recruited 83 men and 120 women, who were nonsmokers, 20-40 y of age, with self-reported vegetable and fruit (V&F) intakes of < or = 2.5 or > or = 4.5 servings/d. Diet was assessed by 3-d food record and serum carotenoids were measured as biomarkers of V&F intake (e.g., servings V&F vs. alpha-carotene; r = 0.47, P = 0.0001). Serum beta-glucuronidase activity (Modified Sigma Units/L), determined in blood samples collected on two consecutive days from fasting subjects, was higher in men than women (mean +/- SEM: 20.4 x 10(3) +/- 1.0 x10(3) and 17.0 x 10(3) +/- 0.6 x 10(3), P = 0.002). beta-Glucuronidase activity (adjusted for sex) was inversely associated with intakes of plant protein, fruit, dietary fiber (r = -0.24 to -0.30; P < 0.001), botanical groupings Cucurbitaceae, Rosaceae, and Leguminosae (r = -0.16 to -0.19; P < 0.05), and serum alpha- and beta-carotene and beta-cryptoxanthin (r = -0.18 to -0.26; P < or = 0.01). Activity was not associated with overall vegetable intake. Although these associations are modest, the data suggest that plant foods, particularly constituents of fruits and fiber-containing foods, may influence human beta-glucuronidase activity in a potentially favorable direction.
authors.affiliation: Cancer Prevention Research Program, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA. jlampe@fhcrc.org
authors.forename: Johanna W
authors.initials: JW
authors.lastname: Lampe
authors.forename: Shuying S
authors.initials: SS
authors.lastname: Li
authors.forename: John D
authors.initials: JD
authors.lastname: Potter
authors.forename: Irena B
authors.initials: IB
authors.lastname: King
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D002338:Carotenoids / Q000097:blood; D015930:Diet Records; D004034:Diet Surveys; D004043:Dietary Fiber / Q000008:administration & dosage / Q000378:metabolism; D005260:Female; D005638:Fruit / Q000737:chemistry*; D005966:Glucuronidase / Q000097:blood*; D006801:Humans; D008099:Liver / Q000201:enzymology*; D008297:Male; D010940:Plant Proteins / Q000008:administration & dosage* / Q000378:metabolism; D012737:Sex Factors; D014675:Vegetables / Q000737:chemistry*
chemical_list: D015415:Biomarkers; D004043:Dietary Fiber; D010940:Plant Proteins; D002338:Carotenoids; D005966:Glucuronidase