Theophylline Prevents Dexamethasone-Induced Atrophy in C2C12 Myotubes

Area of Science:

• Biochemistry
• Molecular Biology
• Physiology

Background:

• Skeletal muscle mass relies on protein synthesis and degradation balance.
• Muscle wasting, or atrophy, significantly impacts healthspan and quality of life.
• Glucocorticoids are known inducers of skeletal muscle atrophy.

Purpose of the Study:

• To investigate the potential of theophylline in preventing glucocorticoid-induced muscle atrophy.
• To elucidate the molecular mechanisms underlying theophylline's protective effects.

Main Methods:

• Utilized C2C12 myotubes as a model system.
• Assessed myosin heavy chain expression to quantify muscle atrophy.
• Performed pull-down assays to study receptor interactions.
• Measured protein phosphorylation and nuclear translocation.

Main Results:

• Theophylline demonstrated significant preventive activity against dexamethasone-induced muscle atrophy.
• Theophylline inhibited the expression of ubiquitin ligases MuRF1 and Cbl-b.
• Theophylline competitively bound to the glucocorticoid receptor, inhibiting its nuclear translocation.
• Theophylline suppressed dexamethasone-induced phosphorylation of p38 and FoxO3a.

Conclusions:

• Theophylline acts as an antagonist to glucocorticoid receptors.
• Theophylline effectively prevents glucocorticoid-induced muscle atrophy through multiple molecular pathways.
• Theophylline presents a promising natural food ingredient for mitigating skeletal muscle atrophy.