Urolithin A improves muscle function by inducing mitophagy in muscular dystrophy

Area of Science:

• Biochemistry
• Cell Biology
• Genetics

Background:

• Duchenne muscular dystrophy (DMD) is a common genetic disorder characterized by progressive muscle degeneration.
• Mitochondrial dysfunction is implicated in DMD pathogenesis, but the underlying mechanisms are not fully understood.
• Reduced mitophagy, the selective degradation of damaged mitochondria, is a potential contributor to mitochondrial dysfunction in DMD.

Purpose of the Study:

• To investigate the role of mitophagy in DMD.
• To evaluate the therapeutic potential of the mitophagy activator urolithin A (UA) in DMD models.

Main Methods:

• Assessed mitophagy markers in skeletal muscle and muscle stem cells (MuSCs) from DMD mouse models and DMD patient myoblasts.
• Administered UA to DMD worms, mice, and primary myoblasts.
• Measured skeletal muscle respiratory capacity, MuSC regenerative ability, muscle function, and survival rates in treated DMD models.

Main Results:

• DMD models exhibited reduced mitophagy markers in skeletal muscle and MuSCs.
• UA administration restored mitophagy in DMD worms, mice, and patient-derived myoblasts.
• UA treatment improved skeletal muscle respiration, enhanced MuSC regeneration, and recovered muscle function.
• UA significantly increased survival rates in DMD mouse models.

Conclusions:

• Reduced mitophagy contributes to mitochondrial dysfunction and disease progression in Duchenne muscular dystrophy.
• Restoration of mitophagy via UA administration alleviates DMD symptoms and improves muscle health.
• Urolithin A shows therapeutic potential for treating Duchenne muscular dystrophy and potentially other muscular dystrophies.