Open AccessVitamin D Receptor Signaling Inhibits Atherosclerosis in Mice
Author(s) -
Frances L. Szeto,
Catherine A. Reardon,
David Yoon,
Youli Wang,
Kari E. Wong,
Yunzi Chen,
Juan Kong,
Shu Q. Liu,
Ravi Thadhani,
Godfrey S. Getz,
Yan Chun Li
Publication year - 2012
Publication title -
molecular endocrinology
Language(s) - English
Resource type - Journals
eISSN - 1944-9917
pISSN - 0888-8809
DOI - 10.1210/me.2011-1329
Subject(s) - calcitriol receptor , ldl receptor , endocrinology , medicine , biology , receptor , macrophage , vitamin d and neurology , proinflammatory cytokine , cholesterol , lipoprotein , inflammation , immunology , biochemistry , in vitro
Although vitamin D has been implicated in cardiovascular protection, few studies have addressed the role of vitamin D receptor (VDR) in atherosclerosis. Here we investigate the effect of inactivation of the VDR signaling on atherogenesis and the antiatherosclerotic mechanism of vitamin D. Low density lipoprotein receptor (LDLR)(-/-)/VDR(-/-) mice exhibited site-specific accelerated atherogenesis, accompanied by increases in adhesion molecules and proinflammatory cytokines in the aorta and cholesterol influx in macrophages. Macrophages showed marked renin up-regulation in the absence of VDR, and inhibition of renin by aliskiren reduced atherosclerosis in LDLR(-/-)/VDR(-/-) mice, suggesting that the renin-angiotensin system (RAS) promotes atherosclerosis in the absence of VDR. LDLR(-/-) mice receiving LDLR(-/-)/VDR(-/-) BMT developed larger lesions than LDLR(-/-) BMT controls. Moreover, LDLR(-/-) mice receiving Rag-1(-/-)/VDR(-/-) BMT, which were unable to generate functional T and B lymphocytes, still had more severe atherosclerosis than Rag-1(-/-) BMT controls, suggesting a critical role of macrophage VDR signaling in atherosclerotic suppression. Aliskiren treatment eliminated the difference in lesions between Rag-1(-/-)/VDR(-/-) BMT and Rag-1(-/-) BMT recipients, indicating that local RAS activation in macrophages contributes to the enhanced atherogenesis seen in Rag-1(-/-)/VDR(-/-) BMT mice. Taken together, these observations provide evidence that macrophage VDR signaling, in part by suppressing the local RAS, inhibits atherosclerosis in mice.