TNF and obesity due to melanocortin 4 receptor deficiency: It is believed that ω-3 polyunsaturated fatty acids (PUFAs) exhibit significant effects on improved insulin sensitivity and obesity, and early study further revealed the effect of ω-3 PUFAs on metabolic is mainly exerted by activating SIRT1 and ensures inhibition of the release of proinflammatory cytokine including IL-6 and TNF-α (57, 58).