Oxidized LDL upregulates macrophage DPP4 expression via TLR4/TRIF/CD36 pathways

Rao, Xiaoquan; Zhao, Shi; Braunstein, Zachary; Mao, Hong; Razavi, Michael; Duan, Lihua; Wei, Yingying; Toomey, Amelia C.; Rajagopalan, Sanjay; Zhong, Jixin

Monocytes and macrophages are central effectors of innate immunity and are now recognized as key pathophysiologic players in the development of various chronic conditions such as atherosclerosis [16, 17] . Our recent study indicates that DPP4 expression on circulating monocytes was increased in atherosclerosis and was associated with atherosclerotic burden [14] . Since DPP4 up-regulation has been associated with obesity [8, 9, 11] , we divided patients into two groups: obese (BMI ≥ 30) and non-obese (BMI b 30). The biological characteristics and markers are shown in Table 1 . There were no significant differences in age, SBP, DBP, HR, and biochemical parameters such as aspartate transaminase (AST), alanine transaminase (ALT), creatinine, creatine kinase, alkaline phosphatase, albumin, sodium, potassium, chloride, HDL\ \C, blood urea nitrogen, and total protein. The levels of HOMA-IR, non-HDL cholesterol, uric acid, triglycerides, fasting blood glucose, fasting insulin, and leptin were significantly increased, while adiponectin levels were lower in obese patients with atherosclerosis (Table 1) .