Myostatin Activates the Ubiquitin-Proteasome and Autophagy-Lysosome Systems Contributing to Muscle Wasting in Chronic Kidney Disease

Figure 6

Suppression of myostatin inhibits the ubiquitin-proteasome and autophagy-lysosome systems in myotubes despite the presence of TNF-α. C2C12 cells were transfected with myostatin siRNA (myostatin) versus control scrambled siRNA (Control). After differentiating into myotubes, cells were treated with 100 ng/mL TNF-α for 24 h. (a) Left: representative immunoblotting of Atg3, Atg7, Atg12, Beclin-1, LC3-I/II, and GAPDH. Right: The ratio of Atg3, Atg7, Atg12, Beclin-1, LC3-II, and GAPDH normalized to control. (b) Left: representative immunoblotting of MAFbx, MuRF1, and GAPDH. Right: the ratio of MAFbx, MuRF1 and GAPDH normalized to control. (c) Left: representative immunoblotting of PAMA4, Rpt5, Rpn11, and GAPDH. Right: The ratio of PAMA4, Rpt5, Rpn11 and GAPDH normalized to control. (d) Left: representative immunoblotting of p-PI3K, p-Akt, p-FoxO3a, and GAPDH. Right: The ratio of p-PI3K, p-Akt, p-FoxO3a, and GAPDH normalized to control. Values were described means, with SD represented by vertical bars. Significantly different () from control group, (^†, independent experiments) from TNF-α group.

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