The serum exosomes of Elafin-overexpressing HFD-treated mice showed an increase in miR-181b-5p and miR-219-5p, which can induce the expression of appetite reducing leptin in mouse mesenteric fat, thereby reducing obesity, hyperglycemia, and hepatic steatosis. The gene discussed is LEP; the disease is obesity due to melanocortin 4 receptor deficiency.