title: Deletion of class A scavenger receptor deteriorates obesity-induced insulin resistance in adipose tissue.
abstract: Chronic low-grade inflammation, particularly in the adipose tissue, orchestrates obesity-induced insulin resistance. In this process, polarized activation of macrophages plays a crucial role. However, how macrophages contribute to insulin resistance remains obscure. Class A scavenger receptor (SR-A) is a pattern recognition receptor primarily expressed in macrophages. Through a combination of in vivo and in vitro studies, we report here that deletion of SR-A resulted in reduced insulin sensitivity in obese mice. The anti-inflammatory virtue of SR-A was accomplished by favoring M2 macrophage polarization in adipose tissue. Moreover, we demonstrate that lysophosphatidylcholine (LPC) served as an obesity-related endogenous ligand for SR-A promoting M2 macrophage polarization by activation of signal transducer and activator of transcription 6 signaling. These data have unraveled a clear mechanistic link between insulin resistance and inflammation mediated by the LPC/SR-A pathway in macrophages.
authors.affiliation: Atherosclerosis Research Center, Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, Key Laboratory of Cardiovascular Disease and Molecular Intervention, Nanjing Medical University, Nanjing, China.
authors.forename: Xudong
authors.initials: X
authors.lastname: Zhu
authors.forename: Guijuan
authors.initials: G
authors.lastname: Zong
authors.forename: Liu
authors.initials: L
authors.lastname: Zhu
authors.forename: Yuchen
authors.initials: Y
authors.lastname: Jiang
authors.forename: Ke
authors.initials: K
authors.lastname: Ma
authors.forename: Hanwen
authors.initials: H
authors.lastname: Zhang
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhang
authors.forename: Hui
authors.initials: H
authors.lastname: Bai
authors.forename: Qing
authors.initials: Q
authors.lastname: Yang
authors.forename: Jingjing
authors.initials: J
authors.lastname: Ben
authors.forename: Xiaoyu
authors.initials: X
authors.lastname: Li
authors.forename: Yong
authors.initials: Y
authors.lastname: Xu
authors.forename: Qi
authors.initials: Q
authors.lastname: Chen
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism*; D000818:Animals; D016026:Bone Marrow Transplantation; D002478:Cells, Cultured; D007333:Insulin Resistance / Q000502:physiology*; D008244:Lysophosphatidylcholines / Q000378:metabolism; D017737:Macrophages, Peritoneal / Q000502:physiology; D051379:Mice; D018345:Mice, Knockout; D009765:Obesity / Q000150:complications*; D051117:Scavenger Receptors, Class A / Q000235:genetics / Q000378:metabolism*
chemical_list: D008244:Lysophosphatidylcholines; D051117:Scavenger Receptors, Class A