Bioconversion-Based Postbiotics Enhance Muscle Strength and Modulate Gut Microbiota in Healthy Individuals: A...

Area of Science:

• Microbiology
• Human Nutrition
• Exercise Physiology

Background:

• Postbiotics from kefir lactic acid bacteria show potential for modulating gut microbiota and muscle health.
• Kefir lactic acid bacteria-derived postbiotics (KP) were prepared using polyphenol-rich extract and whey protein.

Purpose of the Study:

• To investigate the effects of KP on muscle strength and gut microbiota composition in healthy adults.
• To explore the gut-muscle axis connection through biomarker analysis.

Main Methods:

• A 12-week randomized, double-blind, placebo-controlled trial involving KP or placebo consumption.
• Assessment of handgrip strength, circulating biomarkers (e.g., irisin, IL-1β), and fecal microbiota using 16S rRNA sequencing.
• Correlation analysis between microbial taxa and muscle-related biomarkers.

Main Results:

• KP supplementation significantly increased dominant-hand grip strength, plasma irisin, and decreased IL-1β.
• Gut microbiota profiling showed enrichment of specific beneficial bacteria and reduction of others.
• Positive correlation observed between Faecalibacterium prausnitzii abundance and plasma irisin.

Conclusions:

• KP supplementation demonstrated a modest improvement in grip strength within groups.
• Findings suggest KP may influence muscle health via the gut-muscle axis, involving irisin and anti-inflammatory pathways.
• Kefir-derived postbiotics show preliminary potential for supporting muscle health.