ABSTRACT
Hypercholesterolaemia is a major risk factor for cardiovascular disease and it has been found that some probiotic bacteria possess cholesterol-lowering capabilities. In this study, the ability of the Lab4 probiotic consortium to hydrolyse bile salts, assimilate cholesterol and regulate cholesterol transport by polarised Caco-2 enterocytes was demonstrated. Furthermore, in wild-type C57BL/6J mice fed a high fat diet, 2-weeks supplementation with Lab4 probiotic consortium plus Lactobacillus plantarum CUL66 resulted in significant reductions in plasma total cholesterol levels and suppression of diet-induced weight gain. No changes in plasma levels of very low-density lipoprotein/low-density lipoprotein, high-density lipoprotein, triglycerides, cytokines or bile acids were observed. Increased amounts of total and unconjugated bile acids in the faeces of the probiotic-fed mice, together with modulation of hepatic small heterodimer partner and cholesterol-7α-hydroxylase mRNA expression, implicates bile salt hydrolase activity as a potential mechanism of action. In summary, this study demonstrates the cholesterol-lowering efficacy of short-term feeding of the Lab4 probiotic consortium plus L. plantarum CUL66 in wild-type mice and supports further assessment in human trials.
Subject(s)
Anticholesteremic Agents/pharmacology , Microbial Consortia/drug effects , Probiotics , Animals , Bile Acids and Salts/blood , Bile Acids and Salts/metabolism , Body Weight , Caco-2 Cells , Cholesterol/metabolism , Colon/metabolism , Colon/microbiology , Cytokines/blood , Diet, High-Fat , Humans , Lactobacillus plantarum , Lipids/blood , Liver/metabolism , Mice , Mice, Inbred C57BLABSTRACT
AIM: Liver radiofrequency ablation (RFA) has been shown to disrupt the mechanical component of the gut barrier. The aim of the present study was to investigate the consequences of liver RFA on the biological gut barrier in terms of the effects of bile production rate and bowel inflammatory state on intestinal microflora balance. METHOD: A total of 25 New Zealand rabbits were assigned to five groups (n = 5 per group): group CBD: subjected to common bile duct (CBD) extracorporeal bypass; group CBD-RFA: subjected to CBD bypass plus one session of open liver RFA; group RFA: subjected to liver RFA; group sham: subjected to sham operation; and group TBD: subjected to total bile deviation (TBD). In groups CBD and CBD-RFA, bile production rate was assessed for 48 h. In groups sham and RFA, measurement of biliary glycine conjugates of cholic and deoxycholic acid levels, histopathologic examination of the non-ablated liver tissue, morphometric analysis, and histopathologic examination of the terminal ileum and microbiological analysis of fecal and tissue samples collected from the jejunum and the cecum (and in group TBD) were performed at 48 h post-operation. RESULTS: One session of liver RFA resulted in ablation of 18.7 ± 2.7% of liver weight. Following liver RFA, bile production rate was reduced, while the levels of biliary bile salts were not affected. There was mild injury of the non-ablated liver parenchyma, mild intestinal wall inflammation, intestinal mucosa atrophy, and intestinal microbial population overgrowth. CONCLUSION: Reduced in bile production and mild bowel inflammation secondary to liver RFA impaired the biological gut barrier as manifested by intestinal microflora imbalance.