Abstract 417: Adenosine Diphosphate Ribosyl Cyclase via PI3K-Akt and FOXO3a Up-regulating MMP-9 to Enhance Vascular Smooth Muscle Cell Proliferation and Migration in Mice

2015 ◽  
Vol 117 (suppl_1) ◽  
Author(s):  
Yuming Li ◽  
Haitao Li ◽  
Xinfang Wang ◽  
Junya Wang ◽  
Zhongqiu Li

The current study was designed to explore the mechanisms of vascular smooth muscle cell (VSMC) proliferation and migration induced by adenosine diphosphate ribosyl cyclase(ADPRC). In this study, 32 Male ApoE-/- mice(6 weeks old, 18-22g)on a C57BL/6J background were divided into four groups, which received normal chow (n=8, NC group), high-fat Western-type diet (n=8, 0.25% cholesterol, 21% fat,HFD group), high-fat Western-type diet,infusion of 2,2′-dihydroxyazobenzene(DHAB, a ADPRC inhibitor, 2mg/kg/day, n=8, HFD-DHAB group) intraperitoneally or high-fat Western-type diet,infusion of LY294002(a Inhibitor of Akt, 5mg/kg/d, n=8, HFD-LY group) intraperitoneally, for 10 weeks. 8 male C57BL/6J mice served as control. After 10 weeks, mice were anesthetized with chloral hydrate, aorta was removed and immediately frozen in liquid nitrogen. Aortic atherosclerotic lesions, VSMC proliferation and migration were assessed by histomorphological observation, smooth muscle actin-α(α-SMA)and proliferating cell nuclear antigen (PCNA) examination. ADPRC expression and alterations of Akt, FOXO3a, phospho-FOXO3a and MMP-9 were determined by RT-PCR, Western Blot, Immunohistochemistry or Immunofluorescence. The results showed that, in aortic atherosclerotic lesions derived from atherosclerotic mice of HFD group, an increased VSMC proliferation and migration, reflected by the up-regulation of α-SMA and PCNA expression, were observed followed by increased expression of ADPRC, Akt, FOXO3a, phospho-FOXO3a and MMP-9. The enhanced expression of ADPRC and followed alterations of FOXO3a, phospho-FOXO3a, MMP-9 as well as α-SMA, PCNA, VSMC proliferation and migration were absent in NC group and C57BL/6J control mice. Treatment with DHAB or LY294002 reversed VSMC proliferation, migration and expression of Akt, FOXO3a, phospho-FOXO3a and MMP-9 in HFD-DHAB and HFD-LY group. These data shows that high-fat Western-type diet induced ADPRC may via PI3K-Akt to phosphorylate FOXO3a up-regulating MMP-9 to enhance vascular smooth muscle cell proliferation and migration in mice.

Author(s):  
Mei Li ◽  
Hongmei Zhu ◽  
Xiaoyan Hu ◽  
Fuhua Gao ◽  
Xinxin Hu ◽  
...  

Transmembrane protein 98 (TMEM98) is a novel gene. In a prior study, we have shown that siRNA-mediated knockdown of TMEM98 inhibited interleukin (IL)-8-promoted endothelial cell (EC) adhesion as well as vascular smooth muscle cell (VSMC) proliferation and migration in the vascular endothelial and smooth muscle cells dysfunction. Herein, we used gain- and loss-of-function approaches combined with biochemical techniques to further explore the role of TMEM98 in the vascular wall cell. The expression and secretion of TMEM98 was increased in cultured human umbilical vein endothelial cells (HUVECs) and VSMCs treated with IL-8 and platelet-derived growth factor (PDGF)-BB. Also, PDGF-BB secretion was increased in TMEM98-treated HUVECs and VSMCs. Thus, it appears that TMEM98 and PDGF-BB form a positive feedback loop in potentiation of EC adhesion as well as VSMC proliferation and migration. Knockdown of TMEM98 mediated by siRNA inhibited PDGF-BB-promoted EC adhesion by downregulating the expression of ICAM-1 and VCAM-1 as well as impaired the proliferation and migration of VSMCs through suppressing the AKT/GSK3β/cyclin D1 signaling pathway and reducing the expression of β-catenin. Hence, TMEM98 promoted EC adhesion through inducing the expression of ICAM-1/VCAM-1 and triggered VSMC proliferation and migration through activating the ERK and AKT/GSK3β signaling pathways. Taken together, TMEM98 may serve as a potential therapeutic target for the clinical treatment.


2013 ◽  
Vol 33 (suppl_1) ◽  
Author(s):  
Pan Li ◽  
Bing Yi ◽  
Qing Qin ◽  
Ming Chen ◽  
Xiaohua You ◽  
...  

Background Abnormal phenotypic switch of vascular smooth muscle cell (VSMC) is a hallmark of vascular disorders such as atherosclerosis and restenosis after angioplasty. Recently, microRNAs (miRNAs) emerge as critical regulators for vascular smooth muscle cell (VSMC) function. Our initial study identified miR-663 as one of the most sharply downregulated miRNAs in human proliferative aortic smooth muscle cells. Hypothesis MiR-663 is implicated in human VSMC phenotypic switch and the development of neointima formation. Methods and Results By using quantitative real-time PCR (qRT-PCR), we found that microRNA-663 (miR-663) was significantly downregulated in cultured human aortic VSMCs upon platelet-derived growth factor (PDGF) treatment, whereas its expression was markedly increased during VSMC differentiation as induced by either retinoid acid or SMC differentiation medium, a condition which induces SMC differentiation and inhibits cell proliferation. Furthermore, we demonstrated that overexpression of miR-663 significantly increased the expression of VSMC differentiation marker genes, such as SM22α, SM α-action, calponin, and SM myosin heavy chain, suggesting that miR-663 is a novel modulator implicated in human VSMC phenotypic switch. Moreover, miR-663 potently inhibited PDGF induced VSMC proliferation and migration. Mechanistically, we identified JunB as a downstream target of miR-663 in human VSMCs. Indeed, overexpression of miR-663 markedly inhibited the expression of the transcription factor JunB as well as its downstream molecules including matrix metallopeptidase-9 (MMP-9) and myosin light chain-9 (Myl9), thus inhibiting VSMC proliferation and migration. Finally, we showed that adeno-miR-663 markedly suppressed the neointimal lesion formation by approximately 50% in mice after vascular injury induced by carotid artery ligation, specifically via decreased JunB expression. Conclusion These results indicate that miR-663 is a novel modulator implicated in human VSMC phenotypic switch through targeting JunB expression and suggest that specific modulation of miR-663 in human VSMCs may represent a novel and attractive approach for the treatment of vascular proliferative diseases.


2020 ◽  
Vol 40 (6) ◽  
Author(s):  
Haijun Wang ◽  
Zheng Wei ◽  
Hulun Li ◽  
Yinghui Guan ◽  
Zhiyang Han ◽  
...  

Abstract Vascular smooth muscle cell (VSMC) proliferation and migration are vital to atherosclerosis (AS) development and plaque rupture. MicroRNA-377-3p (miR-377-3p) has been reported to inhibit AS in apolipoprotein E knockout (ApoE−/−) mice. Herein, the mechanism underlying the effect of miR-377-3p on alleviating AS is explored. In vivo experiments, ApoE−/− mice were fed with high-fat diet (HFD) to induce AS and treated with miR-377-3p agomir or negative control agomir (agomir-NC) on week 0, 2, 4, 6, 8, 10 after HFD feeding. MiR-377-3p was found to restore HFD-induced AS lesions and expressions of matrix metalloproteinase (MMP)-2, MMP-9, α-smooth muscle actin (α-actin) and calponin. In in vitro experiments, human VSMCs were tranfected with miR-377-3p agomir or agomir-NC, followed by treatment with oxidized low-density lipoprotein (ox-LDL). MiR-377-3p was observed to significantly inhibit ox-LDL-induced VSMC proliferation characterized by inhibited cell viability, expressions of proliferating cell nuclear antigen (PCNA), cyclin D1 and cyclin E and cell cycle transition from G1 to S phase accompanied with less 5-Ethynyl-2′-deoxyuridine (EdU)-positive cells. Furthermore, MiR-377-3p significantly inhibited ox-LDL-induced VSMC migration characterized by inhibited wound closure and decreased relative VSMC migration. Besides, neuropilin2 (NRP2) was verified as a target of miR-377-3p. MiR-377-3p was observed to inhibit NRP2 expressions in vivo and in vitro. Moreover, miR-377-3p significantly inhibited MMP-2 and MMP-9 expressions in human VSMCs. Additionally, miR-377-3p-induced inhibition of VSMC proliferation and migration could be attenuated by NRP2 overexpression. These results indicated that miR-377-3p inhibited VSMC proliferation and migration via targeting NRP2. The present study provides an underlying mechanism for miR-377-3p-based AS therapy.


2015 ◽  
Vol 112 (16) ◽  
pp. 5153-5158 ◽  
Author(s):  
Umit A. Kayisli ◽  
Murat Basar ◽  
Ozlem Guzeloglu-Kayisli ◽  
Nihan Semerci ◽  
Helen C. Atkinson ◽  
...  

Molecular mechanisms responsible for abnormal endometrial vasculature in women receiving long-acting progestin-only contraceptives (LAPCs) are unknown. We hypothesize that LAPCs impair vascular smooth muscle cell (VSMC) and pericyte proliferation and migration producing thin-walled hyperdilated fragile microvessels prone to bleeding. Proliferating cell nuclear antigen (PCNA) and α-smooth muscle actin (αSMA) double-immunostaining assessed VSMC differentiation and proliferation in endometria from women before and after DepoProvera (Depo) treatment and from oophorectomized guinea pigs (OVX-GPs) treated with vehicle, estradiol (E2), medroxyprogesterone acetate (MPA), or E2+MPA. Whole-genome profiling, proliferation, and migration assays were performed on cultured VSMCs treated with MPA or etonogestrel (ETO). Endometrial vessels of Depo-administered women displayed reduced αSMA immunoreactivity and fewer PCNA (+) nuclei among αSMA (+) cells (P < 0.008). Microarray analysis of VSMCs identified several MPA- and ETO-altered transcripts regulated by STAT1 signaling (P < 2.22 × 10−6), including chemokine (C-C motif) ligand 2 (CCL2). Both MPA and ETO reduce VSMC proliferation and migration (P < 0.001). Recombinant CCL2 reversed this progestin-mediated inhibition, whereas a STAT1 inhibitor abolished the CCL2 effect. Similarly, the endometria of MPA treated OVX-GPs displayed decreased αSMA staining and fewer PCNA (+) nuclei in VSMC (P < 0.005). In conclusion, LAPCs promote abnormal endometrial vessel formation by inhibiting VSMC proliferation and migration.


2015 ◽  
Vol 35 (suppl_1) ◽  
Author(s):  
Ning Shi ◽  
Xiao-Bing Cui ◽  
Shi-You Chen

Olfactomedin 2 (Olfm2) is a novel regulator for vascular smooth muscle cell (SMC) differentiation, but it is unclear whether Olfm2 is also involved in SMC phenotypic modulation, an important process associated with vascular injury. In this study, we found that Olfm2 was induced during PDGF-BB-induced SMC phenotypic modulation. Olfm2 knockdown attenuated PDGF-BB-induced suppression of SM marker genes including SM myosin heavy chain and SM22α, and also inhibited PDGF-BB-stimulated SMC proliferation and migration. On the other hand, Olfm2 overexpression down-regulated SM markers gene expression, and promoted SMC proliferation marker PCNA expression. Moreover, PDGF-BB slightly induced expression of Runx2, which interfered with the formation of SRF/myocardin ternary complex, but dramatically enhanced SRF-Runx2 interaction, suggesting that certain factors mediate SRF-Runx2 interaction. Indeed, Olfm2 physically interacted with both SRF and Runx2. Blockade of Olfm2 inhibited SRF association with Runx2, leading to increased association between SRF and myocardin, which in turn activated the transcription of SM markers, whereas overexpression of Olfm2 promoted SRF binding to Runx2. These results demonstrated that Olfm2 mediates the interaction between SRF and Runx2, contributing to SMC phenotypic modulation.


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