OXT and obesity due to melanocortin 4 receptor deficiency: It is particularly worth mentioning that although the metabolic benefits of OXT is significantly attributed to the central action of this peptide [14], our studies and others showed that peripheral OXT delivery can work to exert anti-obesity effects [15], [16], and we further revealed that the underlying mechanism is related to the mechanism that peripherally delivered OXT can promote the intra-brain release of OXT to induce the metabolic actions [15].