Thus, lower adiponectin levels [124] and elevated leptin levels [81, 127], proinflammatory cytokines and chemokines [128–130], and reactive oxygen species (ROS) [44, 131] and esterified fatty acids [104] have been described in PVAT from both obese patients and animal models of obesity (Figure 3). This evidence concerns the gene LEP and obesity due to melanocortin 4 receptor deficiency.