With the PPARγ gene knocked out in obese mice, the expression levels of related genes in M2 type macrophages in adipose tissue decreased by 70% to 80%, while the expression levels of inflammatory genes in M1 type macrophages increased, accompanied by insulin resistance and exacerbated hyperglycemia, suggesting that PPARγ is vital in maintaining M2 macrophage phenotype and recovering insulin sensitivity (86). The gene discussed is PPARG; the disease is Insulin resistance.