title: Probiotics modify tight-junction proteins in an animal model of nonalcoholic fatty liver disease.
abstract: BACKGROUND
  We have investigated the effects of a multispecies probiotic preparation containing a combination of probiotic bacterial genera that included Bifidobacteria, Lactobacilli and a Streptococcus in a mouse model of high-fat diet or obesity-induced liver steatosis.
  
  
  METHODS
  Three groups of C57B1/6J mice were fed either a standard chow or a high-fat diet for 20 weeks, while a third group was fed a high-fat diet for 10 weeks and then concomitantly administered probiotics for a further 10 weeks. Serum, liver and large bowel samples were collected for analysis.
  
  
  RESULTS
  The expression of the tight-junction proteins ZO-1 and ZO-2 was reduced (p < 0.05) in high-fat diet-fed mice compared to chow-fed mice. Probiotic supplementation helped to maintain tight ZO-1 and ZO-2 expression compared with the high-fat diet group (p < 0.05), but did not restore ZO-1 or ZO-2 expression compared with chow-fed mice. Mice fed a high-fat diet ± probiotics had significant steatosis development compared with chow-fed mice (p < 0.05); steatosis was less severe in the probiotics group compared with the high-fat diet group. Hepatic triglyceride concentration was higher in mice fed a high-fat diet ± probiotics compared with the chow group (p < 0.05), and was lower in the probiotics group compared with the high-fat diet group (p < 0.05). Compared with chow-fed mice, serum glucose, cholesterol concentration and the activity of alanine transaminase were higher (p < 0.05), whereas serum triglyceride concentration was lower (p < 0.05) in mice fed a high-fat diet ± probiotics.
  
  
  CONCLUSIONS
  Supplementation with a multispecies probiotic formulation helped to maintain tight-junction proteins ZO-1 and ZO-2, and reduced hepatic triglyceride concentration compared with a high-fat diet alone.
authors.affiliation: School of Human Movement and Nutrition Sciences, The University of Queensland, Brisbane, Queensland, Australia.
authors.forename: David
authors.initials: D
authors.lastname: Briskey
authors.affiliation: Gallipoli Medical Research Centre, Greenslopes Hospital, Brisbane, Australia School of Medicine, The University of Queensland, Brisbane, Australia.
authors.forename: Mandy
authors.initials: M
authors.lastname: Heritage
authors.affiliation: Gallipoli Medical Research Centre, Greenslopes Hospital, Brisbane, Australia School of Medicine, The University of Queensland, Brisbane, Australia.
authors.forename: Lesley-Anne
authors.initials: LA
authors.lastname: Jaskowski
authors.affiliation: School of Biomedical Sciences and Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Australia.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Peake
authors.affiliation: Centre for Kidney Disease Research, School of Medicine, The University of Queensland, Translational Research Institute, Queensland, Australia.
authors.forename: Glenda
authors.initials: G
authors.lastname: Gobe
authors.affiliation: Gallipoli Medical Research Centre, Greenslopes Hospital, Brisbane, Australia Queensland Institute of Medical Research Berghofer Medical Research Institute, Brisbane, Australia Envoi Specialist Pathologists, Brisbane, Australia.
authors.forename: V Nathan
authors.initials: VN
authors.lastname: Subramaniam
authors.affiliation: Gallipoli Medical Research Centre, Greenslopes Hospital, Brisbane, Australia School of Medicine, The University of Queensland, Brisbane, Australia.
authors.forename: Darrell
authors.initials: D
authors.lastname: Crawford
authors.affiliation: Envoi Specialist Pathologists, Brisbane, Australia.
authors.forename: Catherine
authors.initials: C
authors.lastname: Campbell
authors.affiliation: Sydney Medical School, University of Sydney, Medlab Clinical Ltd., Sydney, New South Wales, 2006, Australia.
authors.forename: Luis
authors.initials: L
authors.lastname: Vitetta
keywords: dysbiosis; nonalcoholic fatty liver disease; probiotics; steatosis; tight-junction proteins