For instance, obesity-related inflammation is associated with systemic gut dysbiosis that might increase blood endotoxin levels and activate toll like receptor (TLR)4 in tissue-resident macrophages, triggering the pro-inflammatory cascade and increasing chemoattractant chemokines and promoting immune-cell migration into specific organs, such as the liver [44]. Here, TLR4 is linked to obesity due to melanocortin 4 receptor deficiency.