Receptor activator of nuclear factor (NF)-kappaB ligand (RANKL) increases vascular permeability: impaired permeability and angiogenesis in eNOS-deficient mice.
Receptor activator of nuclear factor (NF)-kappaB ligand (RANKL) is emerging as an important regulator of vascular pathophysiology. Here, we demonstrate a novel role of RANKL as a vascular permeability factor and a critical role of endothelial nitric oxide synthase (eNOS) in RANKL-induced endothelial function. RANKL increased the vascular permeability and leukocyte infiltration in vivo and caused the breakdown of the blood-retinal barrier in wild-type mice but not in eNOS-deficient mice. In vitro, it increased endothelial permeability and reduced VE-cadherin-facilitated endothelial cell-cell junctions in a NO-dependent manner. RANKL also led to the activation of Akt and eNOS and to NO production in endothelial cells (ECs). These effects were suppressed by the inhibition of TRAF6, phosphoinositide 3'-kinase (PI3K), Akt, or NOS by genetic or pharmacologic means. Inhibition of the TRAF6-mediated NO pathway reduced EC migration and capillary-like tube formation in response to RANKL. Moreover, the effects of RANKL on ECs sprouting from the aorta, and neovessel formation in both the mouse Matrigel plug assay and corneal micropocket assay, were impaired in eNOS-deficient mice. These results demonstrate that RANKL promotes vascular permeability and angiogenesis by stimulating eNOS by a TRAF6-PI3K-Akt-dependent mechanism. These properties may be relevant to the pathogenesis of angiogenesis-dependent and inflammatory vascular diseases.
Min
Jeong-Ki
JK
Department of Biochemistry, College of Sciences, Yonsei University, and Department of Ophthalmology, Seoul National University Hospital, Republic of Korea.
Cho
Young-Lai
YL
Choi
Jae-Hoon
JH
Kim
Yonghak
Y
Kim
Jeong Hun
JH
Yu
Young Suk
YS
Rho
Jaerang
J
Mochizuki
Naoki
N
Kim
Young-Myeong
YM
Oh
Goo Taeg
GT
Kwon
Young-Guen
YG
D000818:Animals; D002199:Capillary Permeability; D007365:Intercellular Junctions / Q000502:physiology; D051379:Mice; D018345:Mice, Knockout; D009389:Neovascularization, Pathologic; D052247:Nitric Oxide Synthase Type II / Q000172:deficiency / Q000502:physiology*; D052250:Nitric Oxide Synthase Type III; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D053245:RANK Ligand / Q000502:physiology*; D048029:TNF Receptor-Associated Factor 6 / Q000378:metabolism
D053245:RANK Ligand; D048029:TNF Receptor-Associated Factor 6; C505688:TNFSF11 protein, human; D052247:Nitric Oxide Synthase Type II; D052250:Nitric Oxide Synthase Type III; C496315:Nos3 protein, mouse; D019869:Phosphatidylinositol 3-Kinases; D051057:Proto-Oncogene Proteins c-akt