Osteoprotegerin promotes intimal hyperplasia and contributes to in-stent restenosis: Role of an αVβ3/FAK dependent YAP pathway.

Abnormal proliferation and migration of vascular smooth muscle cells (VSMCs) are related to in-stent-restenosis (ISR) following percutaneous coronary intervention (PCI). Osteoprotegerin (OPG) has been implicated in various vascular diseases. However, the effects of OPG on ISR and the underlying mechanism remained elusive. We here investigated the association between OPG and ISR, and to demonstrate the role and potential mechanisms of OPG in neointimal hyperplasia. From 2962 patients who received coronary angiography and follow-up coronary angiography at approximately one year, 291 patients were diagnosed with ISR, and another 291 gender- and age- matched patients without ISR were selected as controls. Serum OPG levels were significantly increased in patients with ISR. Multivariable logistic regression analysis indicated that OPG level was independently associated with the increased risk of ISR. In a mouse femoral artery wire injury model, upregulated OPG was evidenced in vascular tissue after injury. OPG deletion attenuated the vascular injury-induced neointimal hyperplasia and related gene expression in mice. OPG promoted neointimal hyperplasia and human aortic smooth muscle cell (hASMC) proliferation and migration through activation of yes-associated protein (YAP), a major downstream effector of the Hippo signaling pathway, whereas knockdown or inhibition of YAP in hASMCs blunted OPG-induced above effects. Moreover, we found that OPG, as a ligand for integrin αVβ3, mediated phosphorylation of focal adhesion kinase (FAK) and actin cytoskeleton reorganization, resulting in YAP dephosphorylation in hASMCs. OPG-dependent YAP and VSMC activation was prevented by treatment with αVβ3-blocking antibodies and inhibitors of FAK and actin stress fibers. Increased serum OPG levels are associated with increased risk of ISR following PCI and OPG could promote neointimal hyperplasia in response to injury through integrin αVβ3 mediated FAK and YAP activation, indicating OPG/YAP inhibition might serve as an attractive novel target for the prevention of ISR after PCI.

He Y ，Zou P ，Lu Y ，Jia D ，Li X ，Yang H ，Tang L ，Zhu Z ，Tu T ，Tai S ，Xiao Y ，Chen M ，Lu L ，Zhou S ... -  《-》

Association of Serum HMGB2 Levels With In-Stent Restenosis: HMGB2 Promotes Neointimal Hyperplasia in Mice With Femoral Artery Injury and Proliferation and Migration of VSMCs.

In a previous study, we established diabetic and nondiabetic minipig models with coronary artery in-stent restenosis (ISR). Mass spectrometry showed that high-mobility group box (HMGB) 2 level was higher in ISR than in non-ISR tissue from diabetic minipigs. We here investigated whether serum HMGB2 levels were related to ISR in coronary artery disease patients. The effect of HMGB2 was evaluated in mice with femoral artery wire injury and in human aortic smooth muscle cells. From 2513 patients undergoing coronary artery intervention and follow-up angiography at ≈1 year, 262 patients were diagnosed with ISR, and 298 patients with no ISR were randomly included as controls. Serum HMGB2 levels were significantly higher in patients with ISR than in those without ISR and were associated with ISR severity. Multivariable logistic regression analysis showed that HMGB2 level was independently associated with ISR. In experiments, HMGB2 expression was increased in vascular tissue after injury. Perivascular HMGB2 administration promoted injury-induced neointimal hyperplasia in C57Bl/6 mice compared with in the control, whereas such pathophysiological features were attenuated in Hmgb2-/- mice. Mechanistically, HMGB2 enhanced neointimal hyperplasia in mice and proliferation and migration in human aortic smooth muscle cells by inducing reactive oxygen species through increased p47phox phosphorylation. Knocking down p47phox, however, inhibited HMGB2-induced effects in human aortic smooth muscle cells. Finally, HMGB2-induced effects were significantly declined in receptor of advanced glycation end products knockdown or deficient cells, but not in Toll-like receptor 4 knockdown or deficient cells. Serum HMGB2 levels were associated with ISR in patients. HMGB2 promoted neointimal hyperplasia in mice with arterial wire injury through reactive oxygen species activation.

He YH ，Wang XQ ，Zhang J ，Liu ZH ，Pan WQ ，Shen Y ，Zhu ZB ，Wang LJ ，Yan XX ，Yang K ，Zhang RY ，Shen WF ，Ding FH ，Lu L ... -  《-》

Increased serum TREM-1 level is associated with in-stent restenosis, and activation of TREM-1 promotes inflammation, proliferation and migration in vascular smooth muscle cells.

In-stent restenosis (ISR) remains a major limitation of percutaneous coronary intervention despite improvements in stent design and pharmacological agents, whereas the mechanism of ISR has not been fully clarified. In the present study, we sought to investigate the potential association of serum soluble TREM-1 (sTREM-1) levels with the incidence of ISR. The role of TREM-1 was evaluated in cultured vascular smooth muscle cells (VSMCs). Out of 1683 patients undergoing coronary intervention and follow-up coronary angiography after approximately one year, 130 patients were diagnosed with ISR, and 150 gender- and age-matched patients with no ISR were randomly included as controls. Levels of sTREM-1 were determined by ELISA. The role of TREM-1 signaling in the activation of VSMCs was tested. Serum sTREM-1 concentrations were significantly elevated in patients with than without ISR. Multivariable logistic regression analysis showed that sTREM-1, besides conventional factors, was independently associated with the incidence of ISR. Evident expression of TREM-1 in VSMCs was detected in the neointimal and medial layers of stenotic lesions of mouse carotid ligation models. In cultured VSMCs, expression of TREM-1 was significantly induced upon exposure to lipopolysaccharide. Blocking of TREM-1 with a synthetic inhibitory peptide LP17 dramatically inhibited, whereas TREM-1-activating antibody promoted cellular inflammation, proliferation and migration in VSMCs. These data suggest that TREM-1 is a predictive biomarker of ISR and an important mediator of cellular inflammation, migration, and proliferation in VSMCs. Pharmacological inhibition of TREM-1 may serve as a promising approach to attenuate the progression of ISR.

Wang F ，Li C ，Ding FH ，Shen Y ，Gao J ，Liu ZH ，Chen JW ，Zhang RY ，Shen WF ，Wang XQ ，Lu L ... -  《-》

MFAP4 Promotes Vascular Smooth Muscle Migration, Proliferation and Accelerates Neointima Formation.

Arterial injury stimulates remodeling responses that, when excessive, lead to stenosis. These responses are influenced by integrin signaling in vascular smooth muscle cells (VSMCs). Microfibrillar-associated protein 4 (MFAP4) is an integrin ligand localized to extracellular matrix fibers in the vascular wall. The role of MFAP4 in vascular biology is unknown. We aimed to test the hypothesis that MFAP4 would enhance integrin-dependent VSMC activation. We produced Mfap4-deficient (Mfap4(-/-)) mice and performed carotid artery ligation to explore the role of MFAP4 in vascular biology in vivo. Furthermore, we investigated the effects of MFAP4 in neointimal formation ex vivo and in primary VSMC and monocyte cultures in vitro. When challenged with carotid artery ligation, Mfap4(-/-) mice exhibited delayed neointimal formation, accompanied by early reduction in the number of proliferating medial and neointimal cells, as well as infiltrating leukocytes. Delayed neointimal formation was associated with decreased cross-sectional area of ligated Mfap4(-/-) carotid arteries resulting in lumen narrowing 28 days after ligation. MFAP4 blockade prohibited the formation of neointimal hyperplasia ex vivo. Moreover, we demonstrated that MFAP4 is a ligand for integrin αVβ3 and mediates VSMC phosphorylation of focal adhesion kinase, migration, and proliferation in vitro. MFAP4-dependent VSMC activation was reversible by treatment with MFAP4-blocking antibodies and inhibitors of focal adhesion kinase and downstream kinases. In addition, we showed that MFAP4 promotes monocyte chemotaxis in integrin αVβ3-dependent manner. MFAP4 regulates integrin αVβ3-induced VSMC proliferation and migration, as well as monocyte chemotaxis, and accelerates neointimal hyperplasia after vascular injury.

Schlosser A ，Pilecki B ，Hemstra LE ，Kejling K ，Kristmannsdottir GB ，Wulf-Johansson H ，Moeller JB ，Füchtbauer EM ，Nielsen O ，Kirketerp-Møller K ，Dubey LK ，Hansen PB ，Stubbe J ，Wrede C ，Hegermann J ，Ochs M ，Rathkolb B ，Schrewe A ，Bekeredjian R ，Wolf E ，Gailus-Durner V ，Fuchs H ，Hrabě de Angelis M ，Lindholt JS ，Holmskov U ，Sorensen GL ... -  《-》

Essential role of Pin1 via STAT3 signalling and mitochondria-dependent pathways in restenosis in type 2 diabetes.

Type 2 diabetes (T2D) is associated with accelerated restenosis rates after angioplasty. We have previously proved that Pin1 played an important role in vascular smooth muscle cell (VSMC) cycle and apoptosis. But neither the role of Pin1 in restenosis by T2D, nor the molecular mechanism of Pin1 in these processes has been elucidated. A mouse model of T2D was generated by the combination of high-fat diet (HFD) and streptozotocin (STZ) injections. Both Immunohistochemistry and Western blot revealed that Pin1 expression was up-regulated in the arterial wall in T2D mice and in VSMCs in culture conditions mimicking T2D. Next, increased activity of Pin1 was observed in neointimal hyperplasia after arterial injury in T2D mice. Further analysis confirmed that 10% serum of T2D mice and Pin1-forced expression stimulated proliferation, inhibited apoptosis, enhanced cell cycle progression and migration of VSMCs, whereas Pin1 knockdown resulted in the converse effects. We demonstrated that STAT3 signalling and mitochondria-dependent pathways played critical roles in the involvement of Pin1 in cell cycle regulation and apoptosis of VSMCs in T2D. In addition, VEGF expression was stimulated by Pin1, which unveiled part of the mechanism of Pin1 in regulating VSMC migration in T2D. Finally, the administration of juglone via pluronic gel onto injured common femoral artery resulted in a significant inhibition of the neointima/media ratio. Our findings demonstrated the vital effect of Pin1 on the VSMC proliferation, cell cycle progression, apoptosis and migration that underlie neointima formation in T2D and implicated Pin1 as a potential therapeutic target to prevent restenosis in T2D.

Lv L ，Zhang J ，Zhang L ，Xue G ，Wang P ，Meng Q ，Liang W ... -  《-》