In addition to the improvement of systemic metabolic alterations including glucose metabolism, previous reports demonstrated that FGF21 protected against diabetes-induced renal injuries through anti-fibrotic, anti-inflammatory and anti-oxidative stress effects in db/db mice and in mice with diet-induced obesity and type 2 diabetes [43, 44]. Here, FGF21 is linked to obesity due to melanocortin 4 receptor deficiency.