title: Low serum enterolactone concentration is associated with low colonic Lactobacillus-Enterococcus counts in men but is not affected by a synbiotic mixture in a randomised, placebo-controlled, double-blind, cross-over intervention study.
abstract: The aims of the present study were to assess the possible differences in faecal microbiota between men with a low serum enterolactone concentration and those with a high concentration, and to investigate the impact of a synbiotic mixture on serum enterolactone concentration in men with a low concentration. We compared faecal microbiota between ten men with the lowest serum enterolactone concentration and ten men with the highest concentration at recruitment (n 84). Furthermore, we carried out a randomised, double-blind, placebo-controlled, cross-over intervention study (6-week intervention periods and 4-week washout period) to investigate the impact of a synbiotic mixture (two Lactobacillus strains, one Bifidobacterium strain, one Propionibacterium strain and galacto-oligosaccharides (32 g/l)) on serum enterolactone concentration in fifty-two men who had a concentration < 20 nmol/l. Serum sensitive C-reactive protein (CRP) concentration was measured at the end of the first intervention period. Men with a low serum enterolactone concentration when compared with those with a high concentration had less faecal bacteria, especially those belonging to the Lactobacillus-Enterococcus group (median 8·2 (interquartile range 7·8-8·4) log10 colony-forming units/g v. median 8·8 (interquartile range 8·5-8·9) log10 colony-forming units/g, P= 0·009). The synbiotic mixture that was used did not have a significant effect on serum enterolactone (synbiotic v. placebo ratio 0·96 (95 % CI 0·76, 1·22), P= 0·724) or serum sensitive CRP (synbiotic v. placebo ratio 0·99 (95 % CI 0·74, 1·33), P= 0·954) concentration. Men with a low serum enterolactone concentration harbour less colonic bacteria, especially those belonging to the Lactobacillus-Enterococcus group. A synbiotic mixture does not increase serum enterolactone concentration.
authors.affiliation: Institute of Biomedicine, Pharmacology, PO Box 63, FIN-00014 University of Helsinki, Finland.
authors.forename: Reetta
authors.initials: R
authors.lastname: Holma
authors.affiliation: Valio Limited, R&D, PO Box 30, FIN-00039 Helsinki, Finland.
authors.forename: Riina A
authors.initials: RA
authors.lastname: Kekkonen
authors.affiliation: Valio Limited, R&D, PO Box 30, FIN-00039 Helsinki, Finland.
authors.forename: Katja
authors.initials: K
authors.lastname: Hatakka
authors.affiliation: STAT-Consulting, Vahverokatu 6, FIN-37130 Nokia, Finland.
authors.forename: Tuija
authors.initials: T
authors.lastname: Poussa
authors.affiliation: Institute of Biomedicine, Pharmacology, PO Box 63, FIN-00014 University of Helsinki, Finland.
authors.forename: Heikki
authors.initials: H
authors.lastname: Vapaatalo
authors.affiliation: Institute for Preventive Medicine, Nutrition and Cancer, Folkhälsan Research Center, and Division of Clinical Chemistry, Biomedicum, FIN-00014 University of Helsinki, Finland.
authors.forename: Herman
authors.initials: H
authors.lastname: Adlercreutz
authors.affiliation: Institute of Biomedicine, Pharmacology, PO Box 63, FIN-00014 University of Helsinki, Finland.
authors.forename: Riitta
authors.initials: R
authors.lastname: Korpela
mesh_terms: D015107:4-Butyrolactone / Q000031:analogs & derivatives* / Q000097:blood; D000328:Adult; D003106:Colon / Q000382:microbiology*; D018592:Cross-Over Studies; D003625:Data Collection; D004311:Double-Blind Method; D016983:Enterococcus / Q000502:physiology*; D005243:Feces / Q000382:microbiology; D005247:Feeding Behavior; D006801:Humans; D007778:Lactobacillus / Q000502:physiology*; D017705:Lignans / Q000097:blood*; D008297:Male; D008875:Middle Aged; D058616:Synbiotics; D055815:Young Adult
chemical_list: D017705:Lignans; D015107:4-Butyrolactone; C029497:2,3-bis(3'-hydroxybenzyl)butyrolactone