Notably, the CSA of myofibers was significantly lower only in control mice treated with STZ, whereas mice with myofibers deficient in Cx43 and Cx45 showed similar CSA to that of control mice (Figure 5) and a reduced permeabilization of myofibers (Figure 6), highlighting the role of functional Cx43 and Cx45 HCs in skeletal muscle atrophy induced by diabetes. This evidence concerns the gene GJA1 and diabetes mellitus.