Levilactobacillus brevis from carnivores can ameliorate hypercholesterolemia: In vitro and in vivo mechanistic evidence

Aims: The aim was to explore the probiotic and hypocholesterolaemic potential of two Levilactobacillus brevis strains of carnivore origin along with selected underlying mechanisms.

Methods and results: Levilactobacillus brevis MT950194 and L. brevis MW365351 were analysed in vitro for oro-gastro-intestinal stress tolerance, cholesterol reduction, cholesterol adsorption (through scanning electron microscopy) and bile salt hydrolase (BSH) activity. Strains could survive (>80%) in oro-gastro-intestinal conditions and reduce high amount of cholesterol (35% and 54%) from media containing bile salts (0.3%) as compared with Lactobacillus acidophilus ATCC 4356 and presented the least pathogenicity towards mammalian cells. Exopolysaccharide production, cell surface cholesterol adherence and BSH activity were witnessed as possible cholesterol-lowering mechanisms. In in vivo experiment, the treatments of hypercholesterolaemic rats with L. brevis MT950194, L. brevis MW365351 and their mixture led to significant (p < 0.05) reduction in serum and hepatic cholesterol, low-density lipids, cholesterol ratio, liver steatosis and size of adipocytes. It further ameliorated diet-induced changes in hepatic enzymes.

Conclusions: Levilactobacillus brevis MT950194 and L. brevis MW365351 from carnivores have probiotic pharmacological potential and can reduce serum cholesterol through surface adherence and BSH production.

Significance and impact of the study: These strains may be utilized in treating hypercholesterolaemia and production of low-fat functional foods.