FNDC5 and obesity due to melanocortin 4 receptor deficiency: Literature on anti-inflammatory, anti-oxidative and anti-apoptotic effects of irisin in various pathological conditions such as obesity, type 2 diabetes, non-alcoholic fatty liver disease, chronic liver disease, osteoporosis, hypertension, atherosclerosis, Alzheimer, and cancer, shows promising results [10,11,12,13,14,15,16,17,18].