Microbial-Derived Exerkines Prevent Skeletal Muscle Atrophy.

Area of Science:

• Microbiology
• Exercise Physiology
• Muscle Biology

Background:

• Regular exercise confers numerous systemic health benefits.
• The gut microbiome is increasingly recognized as a mediator of exercise-induced adaptations.
• Skeletal muscle atrophy, often caused by disuse, leads to significant functional decline.

Purpose of the Study:

• To investigate the role of the gut microbiome in mediating exercise benefits on skeletal muscle.
• To determine if cecal microbial transplants (CMTs) from exercise-trained mice can prevent muscle atrophy.
• To identify microbial-derived factors (exerkines) responsible for these effects.

Main Methods:

• Utilized a mouse model of unilateral hindlimb immobilization to induce skeletal muscle atrophy.
• Performed cecal microbial transplants (CMTs) from donor mice (exercise-trained vs. sedentary) into recipient mice.
• Administered purified microbial-derived exerkines identified from the exercise-trained gut microbiome.

Main Results:

• CMTs from exercise-trained donors provided modest protection against skeletal muscle atrophy compared to sedentary donors.
• Direct administration of specific microbial exerkines preserved muscle function in immobilized mice.
• These exerkines effectively prevented skeletal muscle atrophy, independent of the transplant itself.

Conclusions:

• The gut microbiome plays a role in mediating the muscle-protective effects of exercise.
• Microbial exerkines derived from an exercise-trained gut microbiome can directly prevent skeletal muscle atrophy and preserve muscle function.
• Targeting these microbial exerkines represents a potential therapeutic strategy for conditions involving muscle loss.