TNF and obesity due to melanocortin 4 receptor deficiency: Interestingly, the assessment of circulating inflammatory parameters showed that PAI-1, which is upregulated by pro-inflammatory cytokines such as TNF-α (55) and increased in obesity and in diabetes and is involved in thrombosis, atherosclerosis as well as ischemic cardiovascular events (56, 57), was significantly higher in the Lin and HFHS groups, but not in the Hemp group, versus the LFLS group.