LEP and obesity due to melanocortin 4 receptor deficiency: In obesity, PVAT shifts from a vasoprotective to a pro-inflammatory phenotype, characterized by reduced NO availability, increased oxidative stress, and heightened secretion of pro-inflammatory cytokines, such as leptin, TNF-α, and IL-6, while the secretion of anti-inflammatory adipokines, such as adiponectin, is reduced [10,60,61].