Genomic Characterization, Safety Assessment, and Probiotic Potential of a Novel Human-Derived Enterococcus lactis...

Area of Science:

• Microbiology
• Gastroenterology
• Metabolic Disorders

Background:

• Probiotic strains with bile salt hydrolase (BSH) activity show potential for metabolic disorder treatment.
• Targeting the gut-liver axis is a key strategy for managing metabolic diseases.

Purpose of the Study:

• To characterize a novel human-derived Enterococcus strain for its BSH activity and therapeutic potential.
• To investigate the effects of this probiotic strain on a high-cholesterol diet-induced metabolic disorder mouse model.

Main Methods:

• Genomic analysis for safety assessment and in vitro BSH activity assays.
• Oral administration of the Enterococcus strain to C57BL/6J mice on a high-cholesterol diet for eight weeks.
• Histopathological analysis (H&E, Oil Red O staining) and comprehensive organ examination.

Main Results:

• The Enterococcus strain demonstrated potent BSH activity and an excellent in vivo safety profile.
• No significant reduction in serum cholesterol was observed, but hepatic lipid droplet accumulation was markedly reduced.
• The probiotic's BSH activity was linked to modulation of bile acid metabolism, inhibiting hepatic lipid deposition.

Conclusions:

• Enterococcus lactis IOBRA9746 is a safe, BSH-active probiotic with a specific effect on reducing hepatic lipid accumulation.
• This strain represents a potential liver-targeted intervention for metabolic diseases linked to poor diet.
• The therapeutic benefit is independent of systemic cholesterol reduction, highlighting a novel mechanism via the gut-liver axis.