The incubation of 3T3-L1 murine adipocytes in the presence of H2O2 mimics the situation observed during obesity in that it decreases adiponectin and PPARγ expression and increases the expression of pro-inflammatory molecules such as monocyte chemoattractant protein-1 (MCP-1), interleukine-6 (IL-6) and plasminogen activator inhibitor 1 (PAI-I) [200]. Here, CCL2 is linked to obesity due to melanocortin 4 receptor deficiency.