Obesity may affect the liver, at least partly, through the secretion of adipokines (e.g., leptin, adiponectin, resistin, visfatin), which are produced mainly but not exclusively by the adipocytes, and cytokines (e.g., TNF-α, IL-1, IL-6), which are produced mainly by the immune cells infiltrating the adipose tissue when it expands; there is an ever continuing and dynamic interplay among various adipokines and cytokines, exhibiting synergistic or antagonistic action [6, 8]. Here, TNF is linked to obesity due to melanocortin 4 receptor deficiency.