TNF and obesity due to melanocortin 4 receptor deficiency: In addition to their impact on lipolysis, NPs are able, via the cGMP/cGK-I pathway, to modulate and inhibit the secretion of adipokines and cytokines, such as interleukin-6, interleukin-8 (IL-6, IL-8) and TNF-α, by adipose tissue, whose increased secretion has been suggested to play a role in the etiology of the chronic state of low-grade inflammation and insulin resistance associated with obesity [25].