Importance of Plasma Membrane Nanodomains in Skeletal Muscle Regeneration

摘要: Numerous studies showed the importance of skeletal muscle plasma membrane (sarcolemma) in the control of skeletal muscle biology. The emphasis in this review is on the sarcolemmal bioactive lipids decisive for survival, proliferation, differentiation, and function of skeletal muscle cells with the particular concern on muscle stem cells (resident satellite cells, RSC) responsible for muscle regeneration. Nowadays, it is obvious that cholesterol (CHOL), basic component of the lipid rafts (LR) through the control of assembled dystrophin-glycoprotein complexes (DGC), directs muscle fiber contractile properties. Another phospholipid, phosphatidylserine (PS), is a component of the inner plasma membrane leaflet, even though it allows the fusion of myoblasts when exteriorized. Sphingolipids, such as ceramide, sphingosine, sphingosine-1-phosphate, and ganglioside GM3, are important signaling molecules in the charge of RSC activation, their motility, and commitment to particular lineage (myoblasts and myofibroblasts). Phosphoinositides and phosphatidylinositol-4,5-biphosphate (PIP2) specifically establish protoplasmic platforms for protein interactions essential for cell viability and mitochondrial activity. Additionally, both prenylation and palmitoylation of certain proteins (id est, heterotrimeric G proteins) determine their biological activity in signal transduction from G-protein coupled receptors (GPCR). Isoprenoids are therefore crucial for the recruitment and metabolic responses of RSC to physiological and pathological stimuli. Finally, iatrogenic modifications of sarcolemma with hydroxylamines and their derivatives lead to increased resistance of muscle cells to apoptotic stimuli and slow progression of some skeletal muscle dystrophies.