CCL2 and obesity due to melanocortin 4 receptor deficiency: A previous mice study showed an increased expression in proinflammatory genes as obesity progressed, especially genes such as MCP‐1, MIP‐1α, and CD68, which indicate macrophage infiltration (Xu et al., 2003) and progression of obesity (Weisberg et al., 2003; Xu et al., 2003), leading to chronic low‐grade adipose tissue inflammation (Chawla, Nguyen, & Goh, 2011).