IL6 and obesity due to melanocortin 4 receptor deficiency: On the other hand, activation of TLR-4 in adipose tissues occurs through interactions with gut microbiota LPS or adipocyte lipolysis-released free fatty acids, which can induce the secretion of inflammatory adipocytokines (i.e., IL-6 and TNF) in obesity (Cani et al., 2007; Gross et al., 2017).