Abstract
Palmitoylethanolamide (PEA) and ibuprofen (IBU) exert anti-inflammatory effects that may influence skeletal muscle adaptation; however, their impact on muscle proteome dynamics remains unclear. Dynamic proteome profiling was performed in differentiated C2C12 myotubes treated for 36 h with D(2)O and either vehicle control (VC), PEA (10 μM), or IBU (100 μM). Protein-specific fractional synthesis rates (FSR; 1541 proteins) and relative protein abundances at 36 h (3085 proteins) were quantified and compared between treatments and VC. Relative to VC, PEA increased synthesis rates of 101 proteins (p < 0.05), whereas 2 proteins exhibited reduced synthesis. IBU increased synthesis rates of 165 proteins and reduced 7 proteins relative to VC. Both PEA and IBU increased total ribosomal protein synthesis (~80% relative to VC) and increased the abundance of 40S ribosomal subunit proteins (~18% relative to VC at 36 h). In addition, IBU treatment was associated with greater abundance of proteins involved in muscle contraction and extracellular matrix organization, reduced abundance of proteins associated with carbohydrate metabolism (21 proteins), and increased abundance of proteins linked to lipid metabolic pathways (17 proteins), relative to VC. In contrast, PEA-induced abundance differences were largely restricted to ribosomal proteins. These findings demonstrate that PEA and IBU enhance ribosomal protein turnover relative to control, whereas IBU elicits broader treatment-associated proteome remodeling.