Poster abstracts
Poster number 105 submitted by Yuntao Bai
Inflammatory links between air pollution and metabolic syndromes
Cuiqing Liu (Davis Heart and Lung Research Institute), Yuntao Bai (MCDB), Qinghua Sun (Davis Heart and Lung Research Institute), Sanjay Rajagopalan (Davis Heart and Lung Research Institute)
Abstract:
Epidemiological studies have provided a link between air pollution particulate matters (PM) and metabolic disorders. CC-chemokine receptor 2 (CCR2) plays a crucial role in macrophage infiltration into obese adipose tissues. In this study, we aimed to investigate the effects of CCR2 signaling on PM-mediated insulin resistance. C57BL/6 and CCR2-/- mice were fed high-fat diet and exposed to concentrated ambient PM for 17 weeks via Versatile Aerosol Concentrator and Enrichment System. Glucose homeostasis was evaluated via glucose tolerance test and insulin tolerance test; inflammatory cells within visceral adipose tissue were counted using flow cytometry; and insulin signaling was detected via western blot. Our results showed that PM exposure caused insulin resistance, upregulated p38 expression, and recruited more macrophages within adipose tissue in obese wild type mice. These effects were attenuated in CCR2-/- mice. Our date indicate that PM exposure exaggerated the effects of high-fat diet on metabolic disorders; CCR2 may play an important role in PM-mediated insulin resistance through recruiting macrophages into adipose tissues.
References:
Rajagopalan S. Air pollution and type 2 diabetes: mechanistic insights. Diabetes. 2012;61(12):3037-3045.
Shoelson SE. Inflammation and insulin resistance. J Clin Invest. 2006;116(7):1793-1801.
Tsou CL. Critical roles for CCR2 and MCP-3 in monocyte mobilization from bone marrow and recruitment to inflammatory sites. J Clin Invest. 2007;117(4):902-909
Bai Y. Macrophage recruitment in obese adipose tissue. Obes Rev. 2015 Feb;16(2):127-36.
Keywords: Air pollution particulate matters, Insulin resistance, CCR2