title: Improvement of liver function by the administration of oyster extract as a dietary supplement to habitual alcohol drinkers: A pilot study.
abstract: Alcoholic liver disease (ALD) is characterized by elevated serum γ-glutamyltransferase (GGT) activity with hepatic steatosis, hepatitis or occasionally fibrosis that may progress to cirrhosis. The potential therapeutic role of oyster extract (OE) or OE-containing dietary supplements (OE supplement) in ALD has seldom been evaluated. In the present study, 84 adults who had an alcohol-drinking habit and marginally high serum GGT levels were enrolled in a randomized, double-blind, placebo-controlled feeding trial to study the effect on alcohol-impaired liver function as reflected by an increased serum level of GGT, as well as the safety, of an OE supplement. The subjects were randomized to receive either an OE supplement (OE group) or placebo (placebo group). There were 42 subjects (31 males and 11 females) in each group, and all the enrolled subjects entered the study. Four individuals (5%) dropped out for reasons unassociated with the study and 6 other subjects were excluded from the efficacy analysis because they did not maintain the required frequency of alcohol intake. As a result, 38 subjects in the placebo group and 36 in the OE group underwent efficacy assessment. Assays of GGT and other liver enzymes were performed at baseline (week 0) and at weeks 4, 8 and 12 of the intervention period. The mean serum levels of GGT in the placebo group gradually increased, while those in the OE group tended to decrease, although no significant within-group differences were observed for either group. A significant between-group difference in the change of mean GGT from baseline was, however, found at week 12 (P=0.049). No OE supplement-associated untoward side-effects nor any abnormal changes in routine laboratory tests and anthropometric parameters were observed throughout the 12-week intervention. An OE supplement shows promise in reducing risk factors associated with ALD in adults with an alcohol intake habit.
authors.affiliation: Tokyo Branch, Bizen Chemical Co. Ltd., Tokyo 103-0023, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Osaki
authors.affiliation: Okayama Head Office, Bizen Chemical Co. Ltd., Okayama 709-0716, Japan.
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Shimizu
authors.affiliation: Research Center, TTC Co. Ltd., Tokyo 113-0021, Japan.
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Yamamoto
authors.affiliation: Product Formulation Division, Bizen Chemical Co. Ltd., Okayama 709-0716, Japan.
authors.forename: Fumiharu
authors.initials: F
authors.lastname: Miyake
authors.affiliation: Medical Corporation Kenshokai, Fukushima Healthcare Center, Osaka 553-0004, Japan.
authors.forename: Sumio
authors.initials: S
authors.lastname: Kondo
authors.affiliation: Research Center, TTC Co. Ltd., Tokyo 113-0021, Japan.
authors.forename: Hideyo
authors.initials: H
authors.lastname: Yamaguchi
keywords: feeding trial; habitual alcohol drinking; liver function; oyster extract; taurine; γ-glutamyltransferase