title: High serum carotenoids are inversely associated with serum gamma-glutamyltransferase in alcohol drinkers within normal liver function.
abstract: BACKGROUND
  Many studies have reported that the consumption of alcohol induces the generation of free radicals. Moreover, recent studies suggest that serum gamma-glutamyltransferase (gamma-GTP) within its normal range might be an early marker of oxidative stress. In this study, we tested the hypothesis that serum antioxidant carotenoids would be inversely associated with serum gamma-GTP in alcohol drinkers within normal liver function.
  
  
  METHODS
  A total of 266 Japanese men who had received health examination in 2003 participated in the study. The associations of serum gamma-GTP and serum-carotenoid concentrations stratified by alcohol intake levels were evaluated cross-sectionally. The participants were divided into three groups according to their ethanol intake level (non-drinker, less than 1 g/day; light drinker, 1-25 g/day; and moderate and heavy drinkers, 25+ g/day). The multivariate-adjusted geometric means of the serum gamma-GTP concentrations in each tertile of the serum-carotenoid concentrations were calculated after adjustment for ethanol intake, age, body mass index, total cholesterol, triacylglycerols, current tobacco use, and habitual exercise.
  
  
  RESULTS
  The serum gamma-GTP concentrations were significantly high in accordance with the ethanol intake level. In moderate and heavy drinkers, the multivariate-adjusted geometric means of serum gamma-GTP concentrations were significantly low in accordance with the tertiles of the serum lycopene, alpha-carotene, beta-carotene, and beta-cryptoxanthin concentrations.
  
  
  CONCLUSIONS
  The serum antioxidant carotenoids were inversely associated with alcohol-induced increases of serum gamma-GTP in moderate and heavy drinkers within normal liver function.
authors.affiliation: Department of Citrus Research, National Institute of Fruit Tree Science, 485-6 Shimizu-Okitsu-nakachou, Shizuoka-shi, Shizuoka 424-0292, Japan. msugiura@affrc.go.jp
authors.forename: Minoru
authors.initials: M
authors.lastname: Sugiura
authors.forename: Mieko
authors.initials: M
authors.lastname: Nakamura
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Ikoma
authors.forename: Masamichi
authors.initials: M
authors.lastname: Yano
authors.forename: Kazunori
authors.initials: K
authors.lastname: Ogawa
authors.forename: Hikaru
authors.initials: H
authors.lastname: Matsumoto
authors.forename: Masaya
authors.initials: M
authors.lastname: Kato
authors.forename: Makoto
authors.initials: M
authors.lastname: Ohshima
authors.forename: Akihiko
authors.initials: A
authors.lastname: Nagao
mesh_terms: D000328:Adult; D000368:Aged; D000428:Alcohol Drinking / Q000097:blood*; D002338:Carotenoids / Q000097:blood*; D003430:Cross-Sectional Studies; D006801:Humans; D007564:Japan; D016014:Linear Models; D008111:Liver Function Tests; D008297:Male; D008875:Middle Aged; D018384:Oxidative Stress; D012307:Risk Factors; D011795:Surveys and Questionnaires; D005723:gamma-Glutamyltransferase / Q000097:blood*
chemical_list: D002338:Carotenoids; D005723:gamma-Glutamyltransferase