CCL2 and obesity due to melanocortin 4 receptor deficiency: There is evidence that the release of proinflammatory cytokines, such as Tumor Necrosis Factor α (TNFα) and Monocyte chemoattractant protein 1 (MCP-1) that can occur in obesity is driven by stress responses related to WAT expansion, although specific mechanisms involved remain to be elucidated (7).