Disuse deterioration of human skeletal muscle challenged by resistive exercise superimposed with vibration : evidence from structural and proteomic analysis

In the present bed rest (BR) study, 23 volunteers were randomized into 3 subgroups: 60 d BR control (Ctr); BR with resistive exercise (RE; lowerlimb load); and resistive vibration exercise (RVE; RE with superimposed vibration). The aim was to analyze by confocal and electron microscopy the effects of vibration on myofibril and filament integrity in soleus (Sol) and vastus lateralis (VL) muscle; differential proteomics of contractile, cytoskeletal, and costameric proteins (TN-C, ROCK1, and FAK); and expression of PGC1α and atrophy-related master genes MuRF1 and MuRF2. RVE (but not RE) preserved myofiber size and phenotype in Sol and VL by overexpressing MYBPC1 (42%, P≥0.01), WDR1 (39%, P≥0.01), sarcosin (84%, P≥0.01), and CKM (20%, P≥0.01) and prevented myofibrillar ultrastructural damage as detectable by MuRF1 expression. In Sol, cytoskeletal and contractile proteins were normalized by RVE, and TN-C increased (59%, P≥0.01); the latter also with RE (108%, P≥0.01). In VL, the outcomes of both RVE (acting on sarcosin and desmin) and RE (by way of troponinT-slow and MYL2) were similar. RVE appears to be a highly efficient countermeasure protocol against muscle atrophy and ultrastructural and molecular dysregulation induced by chronic disuse.-Salanova, M., Gelfi, C., Moriggi, M., Vasso, M., Viganò, A., Minafra, L., Bonifacio, G., Schiffl, G., Gutsmann, M., Felsenberg, D., Cerretelli, P., Blottner, D. Disuse deterioration of human skeletal muscle challenged by resistive exercise superimposed with vibration: evidence from structural and proteomic analysis.