scholarly journals A Pivotal Role for AP-1-Mediated Osteopontin Expression in the Increased Migration of Vascular Smooth Muscle Cells Stimulated With HMGB1

2021 ◽  
Vol 12 ◽  
Author(s):  
Eun Yeong Jeon ◽  
Seung Eun Baek ◽  
Ji On Kim ◽  
Jong Min Choi ◽  
Eun Jeong Jang ◽  
...  

Migration of vascular smooth muscle cells (VSMCs) plays an essential role in the development of vascular remodeling in the injured vasculatures. Previous studies have identified high-mobility group box 1 (HMGB1) as a principal effector mediating vascular remodeling; however, the mechanisms involved have not been fully elucidated. Thus, this study investigated the role of HMGB1 on VSMC migration and the underlying molecular mechanisms involved. VSMCs were ex plant cultured using rat thoracic aorta, and the cellular migration was measured using wound-healing assay. Osteopontin (OPN) mRNA and protein were determined by reverse transcription polymerase chain reaction (RT-PCR) and Western blot, respectively. The OPN promoter was cloned into pGL3 basic to generate a pLuc-OPN-2284 construct. Migration of VSMCs stimulated with HMGB1 (100ng/ml) was markedly increased, which was significantly attenuated in cells pretreated with MPIIIB10 (100–300ng/ml), a neutralizing monoclonal antibody for OPN as well as in cells deficient of OPN. In VSMCs stimulated with HMGB1, OPN mRNA and protein levels were significantly increased in association with an increased promotor activity of OPN gene. Putative-binding sites for activator protein 1 (AP-1) and CCAAT/enhancer-binding protein beta (C/EBPβ) in the indicated promoter region were suggested by TF Search, and the HMGB1-induced expression of OPN was markedly attenuated in cells transfected with siRNA for AP-1. VSMC stimulated with HMGB1 also showed an increased expression of AP-1. Results of this study suggest a pivotal role for AP-1-induced OPN expression in VSMC migration induced by HMGB1. Thus, the AP-1-OPN signaling axis in VSMC might serve as a potential therapeutic target for vascular remodeling in the injured vasculatures.

Author(s):  
Yeling Ma ◽  
Xin Yu ◽  
Lanmei Zhang ◽  
Juan Liu ◽  
Xuan Shao ◽  
...  

Abstract Uterine spiral artery (SPA) remodeling is a crucial event during pregnancy to provide enough blood supply to maternal–fetal interface and meet the demands of the growing fetus. Along this process, the dynamic change and the fate of spiral artery vascular smooth muscle cells (SPA–VSMCs) have long been debatable. In the present study, we analyzed the cell features of SPA–VSMCs at different stages of vascular remodeling in human early pregnancy, and we demonstrated the progressively morphological change of SPA–VSMCs at un-remodeled (Un-Rem), remodeling, and fully remodeled (Fully-Rem) stages, indicating the extravillous trophoblast (EVT)-independent and EVT-dependent phases of SPA–VSMC dedifferentiation. In vitro experiments in VSMC cell line revealed the efficient roles of decidual stromal cells, decidual natural killer cells (dNK), decidual macrophages, and EVTs in inducing VSMCs dedifferentiation. Importantly, the potential transformation of VSMC toward CD56+ dNKs was displayed by immunofluorescence-DNA in-situ hybridization-proximity ligation and chromatin immunoprecipitation assays for H3K4dime modification in the myosin heavy chain 11 (MYH11) promoter region. The findings clearly illustrate a cascade regulation of the progressive dedifferentiation of SPA–VSMCs by multiple cell types in uterine decidual niche and provide new evidences to reveal the destination of SPA–VSMCs during vascular remodeling.


2015 ◽  
Vol 309 (12) ◽  
pp. E995-E1007 ◽  
Author(s):  
Lisa Rigassi ◽  
Federica Barchiesi Bozzolo ◽  
Eliana Lucchinetti ◽  
Michael Zaugg ◽  
Jürgen Fingerle ◽  
...  

2-Methoxyestradiol (2-ME), a metabolite of estradiol with little affinity for estrogen receptors, inhibits proliferation of vascular smooth muscle cells; however, the molecular mechanisms underlying this effect are incompletely understood. Our previous work shows that 2-ME inhibits initiation (blocks phosphorylation of ERK and Akt) and progression (reduces cyclin expression and increases expression of cyclin inhibitors) of the mitogenic pathway and interferes with mitosis (disrupts tubulin organization). Because the RhoA/ROCK1 pathway (RhoA → ROCK1 → myosin phosphatase targeting subunit → myosin light chain) is involved in cytokinesis, herein we tested the concept that 2-ME also blocks the RhoA/ROCK1 pathway. Because of the potential importance of 2-ME for preventing/treating vascular diseases, experiments were conducted in female human aortic vascular smooth muscle cells. Microarray transcriptional profiling suggested an effect of 2-ME on the RhoA/ROCK1 pathway. Indeed, 2-ME blocked mitogen-induced GTP-bound RhoABC expression and membrane-bound RhoA, suggesting interference with the activation of RhoA. 2-ME also reduced ROCK1 expression, suggesting reduced production of the primary downstream signaling kinase of the RhoA pathway. Moreover, 2-ME inhibited RhoA/ROCK1 pathway downstream signaling, including phosphorylated myosin phosphatase targeting subunit and myosin light chain; the ROCK1 inhibitor H-1152 mimicked these effects of 2-ME; both 2-ME and H-1152 blocked cytokinesis. 2-ME also reduced the expression of tissue factor, yet another downstream signaling component of the RhoA/ROCK1 pathway. We conclude that 2-ME inhibits the pathway RhoA → ROCK1 → myosin phosphatase targeting subunit → myosin light chain, and this likely contributes to the reduced cytokinesis in 2-ME treated HASMCs.


2006 ◽  
Vol 291 (1) ◽  
pp. C50-C58 ◽  
Author(s):  
Mei Han ◽  
Jin-Kun Wen ◽  
Bin Zheng ◽  
Yunhui Cheng ◽  
Chunxiang Zhang

Phenotypic change of vascular smooth muscle cells (VSMCs) from a differentiated to a dedifferentiated state accompanies the early stage of atherosclerosis and restenosis. Although much progress has been made in determining the molecular mechanisms involved in VSMC dedifferentiation, research on VSMC redifferentiation is hindered by the lack of an appropriate complete redifferentiation model. We established an in vitro model of redifferentiation by using postconfluent VSMCs from human umbilical artery. We demonstrated that serum-deprived VSMCs are capable of complete redifferentiation. After serum deprivation, postconfluent cultured human umbilical VSMCs became elongated and spindle shaped, with elevation of myofilament density, and reacquired contraction. Expressions of VSMC-specific contractile proteins, such as smooth muscle (SM) α-actin, SM-myosin heavy chain, calponin, and SM 22α, were increased and reached the levels in differentiated cells after serum deprivation. To determine the molecular mechanism of the phenotypic reversion, the levels of expression, phosphorylation, and binding activity of serum response factor (SRF), a key phenotypic modulator for VSMCs, were measured. The results showed that SRF binding activity with CArG motif was significantly increased after serum deprivation, whereas no changes were found in SRF expression and phosphorylation. The increased SRF binding activity was accompanied by an increase in expression of its coactivators such as myocardin. Furthermore, the phenotypic reversion was markedly inhibited by decoy double-strand oligodeoxynucleotides containing SM α-actin CArG motif, which was able to competitively bind to SRF. The results suggested that serum deprivation results in redifferentiation of human umbilical VSMCs. This novel model of VSMC phenotypic reversion should be valuable for research on vascular disease.


2004 ◽  
Vol 287 (3) ◽  
pp. C807-C813 ◽  
Author(s):  
Mizuo Mifune ◽  
Haruhiko Ohtsu ◽  
Hiroyuki Suzuki ◽  
Gerald D. Frank ◽  
Tadashi Inagami ◽  
...  

Epidermal growth factor (EGF) family ligands have been implicated in cardiovascular diseases because of their enhanced expression in vascular lesions and their promoting effects on growth and migration of vascular smooth muscle cells (VSMCs). Betacellulin (BTC), a novel EGF family ligand, has been shown to be expressed in atherosclerotic lesions and to be a potent growth factor of VSMCs. However, the molecular mechanisms downstream of BTC involved in mediating vascular remodeling remain largely unknown. Therefore, the aim of this study was to examine the effects of BTC on signal transduction, growth, and migration in VSMCs. We found that BTC stimulated phosphorylation of EGF receptor (EGFR) at Tyr1068, which was completely blocked by an EGFR kinase inhibitor, AG-1478. BTC also phosphorylated ErbB2 at Tyr877, Tyr1112, and Tyr1248 and induced association of ErbB2 with EGFR, suggesting their heterodimerization in VSMCs. In postreceptor signal transduction, BTC stimulated phosphorylation of extracellular signal-regulated kinase (ERK)1/2, Akt, and p38 mitogen-activated protein kinase (MAPK). Moreover, BTC stimulated proliferation and migration of VSMCs. ERK and Akt inhibitors suppressed migration markedly and proliferation partially, whereas the p38 inhibitor suppressed migration partially but not proliferation. In addition, we found the presence of endogenous BTC in conditioned medium of VSMCs and an increase of BTC on angiotensin II stimulation. In summary, BTC promotes growth and migration of VSMCs through activation of EGFR, ErbB2, and downstream serine/threonine kinases. Together with the expression and processing of endogenous BTC in VSMCs, our results suggest a critical involvement of BTC in vascular remodeling.


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