FNDC5 and metabolic disease: Li et al. (2017) reported that an injection of irisin reduces ischemia-induced neuronal injury. Lu et al. (2015) demonstrated that systemic administration of irisin has a therapeutic effect against atherosclerotic vascular diseases in diabetics. Park et al. (2015) suggested that irisin facilitates the prevention of hepatic steatosis by attenuating oxidative stress. Batirel et al. (2014) also reported that irisin is a potential target in metabolic diseases such as non-alcoholic fatty liver disease.