TLR4 and Insulin resistance: Interestingly, mice lacking TLR4 are protected against high-fat diet-induced insulin resistance, suggesting that TLR4 is a molecular link between nutrition and inflammation.29 The interaction between LPS and TLR4 induces the synthesis of proinflammatory cytokines, such as TNFα, which in turn work as endogenous inflammatory mediators by interacting with receptors found in different target cells.