Discovery of intestinal microorganisms that affect the improvement of muscle strength

Area of Science:

• Microbiology
• Muscle Physiology
• Gut Microbiome Research

Background:

• The gut microbiome's influence on host physiology is increasingly recognized.
• Specific microbial contributions to complex traits like muscle strength remain largely unexplored.

Purpose of the Study:

• To identify specific gut microbial strains associated with muscle strength enhancement.
• To investigate the direct impact of identified bacteria on muscle strength in vivo.

Main Methods:

• Fecal microbiota transplantation from humans to mice.
• Analysis of gut microbial composition correlated with muscle strength phenotypes.
• Supplementation of aged mice with specific bacterial species (Lactobacillus johnsonii, Limosilactobacillus reuteri).
• Measurement of muscle tissue mRNA expression for follistatin (FST) and insulin-like growth factor-1 (IGF1).

Main Results:

• Gut bacteria significantly impact host muscle strength.
• Distinct microbial communities in the gastrointestinal tract correlate with varying muscle strength levels.
• Lactobacillus johnsonii and Limosilactobacillus reuteri supplementation enhanced muscle strength in aged mice.
• Supplementation increased FST and IGF1 mRNA expression in muscle tissue.

Conclusions:

• Specific gut bacteria, including L. johnsonii and L. reuteri, can directly improve muscle strength.
• The gut microbiome represents a novel therapeutic target for enhancing muscle function.
• This study establishes a foundation for understanding the microbiome's role in complex physiological traits.