TY - JOUR
T1 - Caveolin-1 Regulates Atherogenesis by Attenuating Low-Density Lipoprotein Transcytosis and Vascular Inflammation Independently of Endothelial Nitric Oxide Synthase Activation
AU - Ramírez, Cristina M.
AU - Zhang, Xinbo
AU - Bandyopadhyay, Chirosree
AU - Rotllan, Noemi
AU - Sugiyama, Michael G.
AU - Aryal, Binod
AU - Liu, Xinran
AU - He, Shun
AU - Kraehling, Jan R.
AU - Ulrich, Victoria
AU - Lin, Chin Sheng
AU - Velazquez, Heino
AU - Lasunción, Miguel A.
AU - Li, Guangxin
AU - Suárez, Yajaira
AU - Tellides, George
AU - Swirski, Filip K.
AU - Lee, Warren L.
AU - Schwartz, Martin A.
AU - Sessa, William C.
AU - Fernández-Hernando, Carlos
PY - 2019/7/16
Y1 - 2019/7/16
N2 - BACKGROUND: Atherosclerosis is driven by synergistic interactions between pathological, biomechanical, inflammatory, and lipid metabolic factors. Our previous studies demonstrated that absence of caveolin-1 (Cav1)/caveolae in hyperlipidemic mice strongly inhibits atherosclerosis, which was attributed to activation of endothelial nitric oxide (NO) synthase (eNOS) and increased production of NO and reduced inflammation and low-density lipoprotein trafficking. However, the contribution of eNOS activation and NO production in the athero-protection of Cav1 and the exact mechanisms by which Cav1/caveolae control the pathogenesis of diet-induced atherosclerosis are still not clear. METHODS: Triple-knockout mouse lacking expression of eNOS, Cav1, and Ldlr were generated to explore the role of NO production in Cav1-dependent athero-protective function. The effects of Cav1 on lipid trafficking, extracellular matrix remodeling, and vascular inflammation were studied both in vitro and in vivo with a mouse model of diet-induced atherosclerosis. The expression of Cav1 and distribution of caveolae regulated by flow were analyzed by immunofluorescence staining and transmission electron microscopy. RESULTS: We found that absence of Cav1 significantly suppressed atherogenesis in Ldlr-/-eNOS-/- mice, demonstrating that athero-suppression is independent of increased NO production. Instead, we find that the absence of Cav1/caveolae inhibited low-density lipoprotein transport across the endothelium and proatherogenic fibronectin deposition and disturbed flow-mediated endothelial cell inflammation. Consistent with the idea that Cav1/caveolae may play a role in early flow-dependent inflammatory priming, distinct patterns of Cav1 expression and caveolae distribution were observed in athero-prone and athero-resistant areas of the aortic arch even in wild-type mice. CONCLUSIONS: These findings support a role for Cav1/caveolae as a central regulator of atherosclerosis that links biomechanical, metabolic, and inflammatory pathways independently of endothelial eNOS activation and NO production.
AB - BACKGROUND: Atherosclerosis is driven by synergistic interactions between pathological, biomechanical, inflammatory, and lipid metabolic factors. Our previous studies demonstrated that absence of caveolin-1 (Cav1)/caveolae in hyperlipidemic mice strongly inhibits atherosclerosis, which was attributed to activation of endothelial nitric oxide (NO) synthase (eNOS) and increased production of NO and reduced inflammation and low-density lipoprotein trafficking. However, the contribution of eNOS activation and NO production in the athero-protection of Cav1 and the exact mechanisms by which Cav1/caveolae control the pathogenesis of diet-induced atherosclerosis are still not clear. METHODS: Triple-knockout mouse lacking expression of eNOS, Cav1, and Ldlr were generated to explore the role of NO production in Cav1-dependent athero-protective function. The effects of Cav1 on lipid trafficking, extracellular matrix remodeling, and vascular inflammation were studied both in vitro and in vivo with a mouse model of diet-induced atherosclerosis. The expression of Cav1 and distribution of caveolae regulated by flow were analyzed by immunofluorescence staining and transmission electron microscopy. RESULTS: We found that absence of Cav1 significantly suppressed atherogenesis in Ldlr-/-eNOS-/- mice, demonstrating that athero-suppression is independent of increased NO production. Instead, we find that the absence of Cav1/caveolae inhibited low-density lipoprotein transport across the endothelium and proatherogenic fibronectin deposition and disturbed flow-mediated endothelial cell inflammation. Consistent with the idea that Cav1/caveolae may play a role in early flow-dependent inflammatory priming, distinct patterns of Cav1 expression and caveolae distribution were observed in athero-prone and athero-resistant areas of the aortic arch even in wild-type mice. CONCLUSIONS: These findings support a role for Cav1/caveolae as a central regulator of atherosclerosis that links biomechanical, metabolic, and inflammatory pathways independently of endothelial eNOS activation and NO production.
KW - atherosclerosis
KW - caveolae
KW - extracellular matrix
KW - fibronectins
KW - inflammation
KW - nitric oxide synthase type III
KW - transcytosis
UR - https://www.scopus.com/pages/publications/85069949156
U2 - 10.1161/CIRCULATIONAHA.118.038571
DO - 10.1161/CIRCULATIONAHA.118.038571
M3 - Article
C2 - 31154825
AN - SCOPUS:85069949156
SN - 0009-7322
VL - 140
SP - 225
EP - 239
JO - Circulation
JF - Circulation
IS - 3
ER -