TNF and Insulin resistance: On a biochemical level, the adipose tissue releases inflammatory cytokines (TNFa and IL-6), along with nitric oxide bioavailability, insulin resistance, and oxidized low-density lipoprotein (LDL), which all play a key role in endothelin dysfunction in obese patients [26]. The increased risk of cardiovascular diseases with morbid obesity is evident, but very little evidence exists on vascular health.