TLR4 and obesity due to melanocortin 4 receptor deficiency: Resistin is an adipokine produced in the vascular stroma of human white adipose tissue and has been described as a biological marker for chronic diseases, playing a crucial role in the initiation and progression of obesity, insulin resistance, cardiovascular diseases and cancer through mechanisms that involve the strong activation of inflammatory pathways dependent on Toll-like receptor 4 [4,14].