Irisin Increases Sirtuin 1 to Improve Glucocorticoid-Induced Sarcopenia and Mitochondrial Dysfunction

Area of Science:

• Muscle physiology and metabolic disease research.
• Endocrinology and myokine signaling pathways.

Background:

• Sarcopenia, a global health issue, involves progressive loss of muscle mass, strength, and function.
• Irisin, a myokine from FNDC5, plays a key role in maintaining muscle health.

Purpose of the Study:

• To investigate irisin's efficacy in mitigating glucocorticoid-induced sarcopenia.
• To elucidate the molecular mechanisms underlying irisin's protective effects.

Main Methods:

• Utilized a mouse model and C2C12 myotubes treated with dexamethasone.
• Assessed muscle function, histology, and mitochondrial features post-irisin administration.
• Analyzed protein synthesis/degradation and mitochondrial regulators via Western blot.

Main Results:

• FNDC5/irisin levels were reduced in sarcopenic models.
• Exogenous irisin administration improved muscle mass, strength, and mobility.
• Irisin activated SIRT1, suppressing proteasomal degradation and enhancing protein synthesis.
• Irisin promoted mitochondrial biogenesis via PGC-1α signaling.

Conclusions:

• Irisin effectively alleviates glucocorticoid-induced muscle atrophy through SIRT1-dependent pathways.
• Irisin rebalances muscle physiology and systemic energy homeostasis.
• Irisin represents a potential therapeutic strategy for sarcopenia management.