RTN4 and Decreased liver function: In the present study, muscles under pathological conditions including DMD and mouse myopathy models, such as mdx, acute damage induced by myotoxic notexin injection, and chronic muscle damage from liver dysfunction, not only showed altered expression of myogenic factors but also consistently displayed upregulated Nogo-A and downregulated Nogo-C (Figs. 1B and 2A, E, G).