CCL2 and obesity due to melanocortin 4 receptor deficiency: Other studies have also demonstrated that the development of obesity increases the secretions of various pro-inflammatory chemokines and cytokines from adipose tissues, such as tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1β), IL-6 and monocyte chemoattractant protein-1 (MCP-1) [10,11,12].