There are different PAI-1 inducers that can elevate the levels of PAI-1 during obesity such as transforming growth factor (TGF-β), pro-inflammatory mediators like TNF-α, hypoxia-inducible factor (HIF-1α), oxidative stress and dysregulation of the circadian clock [22,23]. This evidence concerns the gene SERPINE1 and obesity due to melanocortin 4 receptor deficiency.