LEP and Insulin resistance: Some of the most important elements of this association are, among others, insulin resistance; overexpression of leptin, inflammatory cytokines, sex hormones, transcriptions factors like NF-κB, AP-1, STAT3, and oxidative stress; and downregulation of the expression of anti-inflammatory factors like adiponectin and PPARγ, which disrupt the balance between cell proliferation and apoptosis.