Fig. 7
Effect of colchicine (COL) treatment on IM muscle. A Representative visualization of IM and COL treatment protocol. B Body mass of VEH and COL treated mice. C Skeletal muscle mass of TA, GAS, and QUAD normalized to body mass. D Representative immunofluorescent images of muscle from VEH and NAC treated IM mice. Samples were stained to identify myosin heavy chain isoform and fiber membrane: type IIA (green), type IIX (red), type IIB (unstained), and dystrophin (DMD, red). Scale bar indicates 50 μm. Quantification of E mean CSA and F distribution of type IIA, IIX, and IIB fibers. G Representative confocal images of mitophagic flux from muscle of IM mt-Keima reporter mice treated with VEH or NAC. Green fluorescence indicates healthy mitochondria. Red fluorescence indicates degrading mitochondria. Scale bar indicates 50 μm. Quantification of H mitophagic (i.e., red) puncta count per field and I average individual mitophagic puncta size. J Quantification of maximal oxygen consumption rate (i.e., respiration) of permeabilized bundles. Simultaneous quantification of K succinate-stimulated mitochondrial (mH2O2) production, and L succinate + pyruvate/malate-stimulated mH2O2 production in permeabilized muscle bundles. Quantification of (M) mitochondrial fraction of electron leak and N OXPHOS coupling. * p < 0.05 compared to VEH group. n = 4–8 per group