CCL2 and obesity due to melanocortin 4 receptor deficiency: Exercise treatment improved the obesity-associated impairment of chemokine production at d3 p.i. The chemokine concentration for CCL2, CCL3, CCL4, CCL5, CCL11, CCL12, CCL19, CCL20, CXCL1, CXCL9, and CXCL10, was ~ 2–3 fold greater in Ob EX mice compared to Ob NO-EX (Fig 6 and S1 Table).