Melanocortin 4 receptor stimulation improves social deficits in mice through oxytocin pathway.

Several studies on humans and mice support oxytocin's role in improving social behaviour, but its use in pharmacotherapy presents some important limiting factors. To date, it is emerging a pharmacological potential for melanocortin 4 receptor (MC4R) agonism in social deficits treatment. Recently, we demonstrated that the deletion of the NFKB1 gene, which encodes the p50 NF-κB subunit, causes impairment in social behaviours, with reductions in social interactions in mice. In this work, we tested the acute effects of THIQ, a selective melanocortin 4 receptor (MC4R) agonist. THIQ treatment increased social interactions both in wild type and p50-/- mice. In particular, after treatment with THIQ, p50-/- mice showed a prosocial behaviour analogous to that of basal WT mice. Moreover, intranasal treatment with an oxytocin antagonist blocked social interactions induced by THIQ, demonstrating that its prosocial effects are mediated by the oxytocin pathway. The data obtained reinforce using MC4R agonists to ameliorate social impairment in NDDs.