Figure 2. Inflammation in obesity.

Rapid growth of adipose tissue leads to quick expansion of adipose tissue. When angiogenesis or vessel dilation can not meet the demand for blood supply, there will be an adipose tissue hypoxia (ATH) from lack of blood supply. ATH will induce angiogenesis and trigger inflammation. Inflammation will promote angiogenesis and vasodilation locally in the tissue for extracellular remodeling. When inflammatory cytokines and fatty acids are elevated in the circulation, they will promote energy expenditure systemically. The inflammatory response may also induce hyperglycemia and energy disposal through glucose excretion in urine. In this way, inflammation acts through insulin resistance and hyperglycemia.