First Author | Grimm M | Year | 2016 |
Journal | Arterioscler Thromb Vasc Biol | Volume | 36 |
Issue | 1 | Pages | 37-48 |
PubMed ID | 26603156 | Mgi Jnum | J:242376 |
Mgi Id | MGI:5905101 | Doi | 10.1161/ATVBAHA.115.306066 |
Citation | Grimm M, et al. (2016) S1P2/G12/13 Signaling Negatively Regulates Macrophage Activation and Indirectly Shapes the Atheroprotective B1-Cell Population. Arterioscler Thromb Vasc Biol 36(1):37-48 |
abstractText | OBJECTIVES: Monocyte/macrophage recruitment and activation at vascular predilection sites plays a central role in the pathogenesis of atherosclerosis. Heterotrimeric G proteins of the G12/13 family have been implicated in the control of migration and inflammatory gene expression, but their function in myeloid cells, especially during atherogenesis, is unknown. APPROACH AND RESULTS: Mice with myeloid-specific deficiency for G12/13 show reduced atherosclerosis with a clear shift to anti-inflammatory gene expression in aortal macrophages. These changes are because of neither altered monocyte/macrophage migration nor reduced activation of inflammatory gene expression; on the contrary, G12/13-deficient macrophages show an increased nuclear factor-kappaB-dependent gene expression in the resting state. Chronically increased inflammatory gene expression in resident peritoneal macrophages results in myeloid-specific G12/13-deficient mice in an altered peritoneal micromilieu with secondary expansion of peritoneal B1 cells. Titers of B1-derived atheroprotective antibodies are increased, and adoptive transfer of peritoneal cells from mutant mice conveys atheroprotection to wild-type mice. With respect to the mechanism of G12/13-mediated transcriptional control, we identify an autocrine feedback loop that suppresses nuclear factor-kappaB-dependent gene expression through a signaling cascade involving sphingosine 1-phosphate receptor subtype 2, G12/13, and RhoA. CONCLUSIONS: Together, these data show that selective inhibition of G12/13 signaling in macrophages can augment atheroprotective B-cell populations and ameliorate atherosclerosis. |