TLR-4 activation further stimulates the IKB kinase/nuclear factor kB (NF-kB) pathway, causing the production of proinflammatory cytokines, such as IL-6, IL-8, TNF, and IL1 (Hypothalamic Inflammation and Obesity: A Mechanistic Review). Here, IL6 is linked to obesity due to melanocortin 4 receptor deficiency.