Another study by this group also that showed exogenous irisin administration for 8 weeks improved the anti-contractile properties of PVAT in thoracic aortas from high-fat diet induced obese mice, suggesting irisin may exert a vasorelaxant effect on obesity-induced increased vasoconstriction [49]. The gene discussed is FNDC5; the disease is obesity due to melanocortin 4 receptor deficiency.