• BMB Reports
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• v.52 no.11
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• pp.665-670
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• 2019

Nucleotide-binding oligomerization domain protein 2 (NOD2), an intracellular pattern recognition receptor, plays important roles in inflammation and cell death. Previously, we have shown that NOD2 is expressed in vascular smooth muscle cells (VSMCs) and that NOD2 deficiency promotes VSMC proliferation, migration, and neointimal formation after vascular injury. However, its role in endoplasmic reticulum (ER) stress-induced cell death in VSMCs remains unclear. Thus, the objective of this study was to evaluate ER stress-induced viability of mouse primary VSMCs. NOD2 deficiency increased ER stress-induced cell death and expression levels of apoptosis mediators (cleaved caspase-3, Bax, and Bak) in VSMCs in the presence of tunicamycin (TM), an ER stress inducer. In contrast, ER stress-induced cell death and expression levels of apoptosis mediators (cleaved caspase-3, Bax, and Bak) were decreased in NOD2-overexpressed VSMCs. We found that the $IRE-1{\alpha}-XBP1$ pathway, one of unfolded protein response branches, was decreased in NOD2-deficient VSMCs and reversed in NOD2-overexpressed VSMCs in the presence of TM. Furthermore, NOD2 deficiency reduced the expression of XBP1 target genes such as GRP78, PDI-1, and Herpud1, thus improving cell survival. Taken together, these data suggest that the induction of ER stress through NOD2 expression can protect against TM-induced cell death in VSMCs. These results may contribute to a new paradigm in vascular homeostasis.

• Journal of Acupuncture Research
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• v.23 no.2
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• pp.21-31
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• 2006

In the present study, We have investigated the bee venom (BV) and melittin (a major component of BV)-mediated anti-proliferative effects, and defined its mechanisms of action in cultured rat aortic vascular smooth muscle cells (VSMCs). BV and melittin $(0.4{\sim}0.8\;{\mu}g/ml)$ effectively inhibited 5% FBS-induced VSMCs proliferations. The regulation of apoptosis has attracted much attention as a possible means of eliminating excessively proliferating VSMCs. In the present study, the treatment of BV and melittin strongly induced apoptosis of VSMCs. These results suggest that the anti-proliferative effects of BV and melittin in VSMCs should be related with induction of apoptosis. Further study about Influence of BV and melittin upon apoptosis mechanism is therefor thought to be necessary to confirm the above results.

• BMB Reports
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• v.55 no.5
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• pp.244-249
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• 2022

Characterized by abnormal proliferation and migration of vascular smooth muscle cells (VSMCs), neointima hyperplasia is a hallmark of vascular restenosis after percutaneous vascular interventions. Vaccinia-related kinase 1 (VRK1) is a stress adaption-associated ser/thr protein kinase that can induce the proliferation of various types of cells. However, the role of VRK1 in the proliferation and migration of VSMCs and neointima hyperplasia after vascular injury remains unknown. We observed increased expression of VRK1 in VSMCs subjected to platelet-derived growth factor (PDGF)-BB by western blotting. Silencing VRK1 by shVrk1 reduced the number of Ki-67-positive VSMCs and attenuated the migration of VSMCs. Mechanistically, we found that relative expression levels of β-catenin and effectors of mTOR complex 1 (mTORC1) such as phospho (p)-mammalian target of rapamycin (mTOR), p-S6, and p-4EBP1 were decreased after silencing VRK1. Restoration of β-catenin expression by SKL2001 and re-activation of mTORC1 by Tuberous sclerosis 1 siRNA (siTsc1) both abolished shVrk1-mediated inhibitory effect on VSMC proliferation and migration. siTsc1 also rescued the reduced expression of β-catenin caused by VRK1 inhibition. Furthermore, mTORC1 re-activation failed to recover the attenuated proliferation and migration of VSMC resulting from shVrk1 after silencing β-catenin. We also found that the vascular expression of VRK1 was increased after injury. VRK1 inactivation in vivo inhibited vascular injury-induced neointima hyperplasia in a β-catenin-dependent manner. These results demonstrate that inhibition of VRK1 can suppress the proliferation and migration of VSMC and neointima hyperplasia after vascular injury via mTORC1/β-catenin pathway.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.2
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• pp.201-207
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• 1998

To evaluate the possibility that the ginseng saponins could be developed as an anti-arteriosclerotic agent, we examined the inhibitory effects of ginseng saponins (total saponin[TS], panaxatriol[PT], panaxadiol[PD]) on the expression of c-fos mRNA and the proliferation of cultured rat aortic vascular smooth muscle cells (VSMCs) stimulated by angiotensin II (Ang II). TS and PT (1.0 mg/ml) suppressed c-fos mRNA induction in VSMCs stimulated by $10^{-5}$ M Ang II. The order of inhibitory potency was PT>TS. Ginseng saponins ($0.01{\sim}1.0$ mg/ml) inhibited the proliferation of VSMCs stimulated by Ang II in a concentration dependent manner, the inhibitory potency was TS＞PT＞PD at $0.1{\sim}1.0$ mg/ml. These results suggest that ginseng saponins may suppress Ang II-stimulated proliferation of aortic VSMCs which can be seen in atherosclerosis, hypertension and restenosis.

• The Korean Journal of Physiology and Pharmacology
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• v.28 no.5
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• pp.449-456
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• 2024

Vascular smooth muscle cells (VSMCs) under biophysical stress play an active role in the progression of vascular inflammation, but the precise mechanisms are unclear. This study examined the cellular expression of monocyte chemoattractant protein 1 (MCP-1) and its related mechanisms using cultured rat aortic VSMCs stimulated with mechanical stretch (MS, equibiaxial cyclic stretch, 60 cycles/min). When the cells were stimulated with 10% MS, MCP-1 expression was markedly increased compared to those in the cells stimulated with low MS intensity (3% or 5%). An enzyme-linked immunosorbent assay revealed an increase in HMGB1 released into culture media from the cells stimulated with 10% MS compared to those stimulated with 3% MS. A pretreatment with glycyrrhizin, a HMGB1 inhibitor, resulted in the marked attenuation of MCP-1 expression in the cells stimulated with 10% MS, suggesting a key role of HMGB1 on MCP-1 expression. Western blot analysis revealed higher PDGFR-α and PDGFR-β expression in the cells stimulated with 10% MS than 3% MS-stimulated cells. In the cells deficient of PDGFR-β using siRNA, but not PDGFR-α, HMGB1 released into culture media was significantly attenuated in the 10% MS-stimulated cells. Similarly, MCP-1 expression induced in 10% MS-stimulated cells was also attenuated in cells deficient of PDGFR-β. Overall, the PDGFR-β signaling plays a pivotal role in the increased expression of MCP-1 in VSMCs stressed with 10% MS. Therefore, targeting PDGFR-β signaling in VSMCs might be a promising therapeutic strategy for vascular complications in the vasculatures under excessive biophysical stress.

• Food Science of Animal Resources
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• v.40 no.1
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• pp.106-117
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• 2020

Cellular senescence is associated with age-related vascular disorders and has been implicated in vascular dysfunctions. Here, we show that duck oil-loaded nanoemulsion (DO-NE) attenuates premature senescence of vascular smooth muscle cells (VSMCs) triggered by angiotensin II (Ang II). Compared with control nanoemulsion (NE), DO-NE significantly inhibited the activity of senescence-associated β-galactosidase, which is a biomarker of cellular senescence, in Ang II-treated VSMCs. SIRT1 protein expression was dose- and time-dependently induced in VSMCs exposed to DO-NE, but not in those exposed to NE, and SIRT1 promoter activity was also elevated. Consistently, DO-NE also dose-dependently rescued Ang II-induced repression of SIRT1 expression, indicating that SIRT1 is linked to the anti-senescence action of DO-NE in VSMCs treated with Ang II. Furthermore, the SIRT1 agonist resveratrol potentiated the effects of DO-NE on VSMCs exposed to Ang II, whereas the SIRT1 inhibitor sirtinol elicited the opposite effect. These findings indicate that DO-NE inhibits senescence by upregulating SIRT1 and thereby impedes vascular aging triggered by Ang II.

• Preventive Nutrition and Food Science
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• v.18 no.2
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• pp.92-97
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• 2013

The calcification of vascular smooth muscle cells (VSMCs) is considered one of the major contributors for vascular disease. Phosphate is known as the inducer for VSMC calcification. In this study, we assessed whether phosphate affected cell viability and fetuin-A, a calcification inhibitor protein, both which are related to VSMC calcification. Also, VSMC viability by zinc level was assessed. The results showed that phosphate increased Ca and P deposition in VSMCs (A7r5 cell line, rat aorta origin). This phosphate-induced Ca and P deposition was consistent with the decreased A7r5 cell viability (P<0.05), which implies phosphate-induced calcification in A7r5 cells might be due to the decreased VSMC cell viability. As phosphate increased, the protein expression of fetuin-A protein was up-regulated. A7r5 cell viability decreased as the addition of cellular zinc level was decreased (P<0.05). The results suggested that zinc deficiency causes the decreased cell viability and it would be the future study to clarify how zinc does act for VSMC cell viability. The results suggest that the decreased VSMC viability by high P or low Zn in VSMCs may be the risk factor for vascular disease.

• BMB Reports
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• v.50 no.12
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• pp.628-633
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• 2017

Gastrin-releasing peptide (GRP) has been reported to be implicated in the pathogenesis of inflammatory disorders. The migration and proliferation of vascular smooth muscle cells (VSMCs) are key components of vascular inflammation that leads to the development of atherosclerosis. The present study aimed to investigate the molecular effect of GRP on VSMC proliferation and migration. We report that GRP significantly enhanced the proliferation and migration of rat VSMCs. GRP increased mRNA and protein expression of matrix metalloproteinase-2 and -9 (MMP-2/9) in VSMCs. The induction of MMP-2/9 by GRP was regulated by the activation of the signal transducer and activator of transcription-3 (STAT3). In addition, STAT3-knockdown of VSMCs by siRNA or blockade of the GRP receptor inhibited GRP-induced migration of VSMCs. Taken together, our findings indicate that GRP promotes the migration of VSMCs through upregulation of MMP-2/9 via STAT3 activation.

• The Korean Journal of Physiology and Pharmacology
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• v.22 no.3
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• pp.349-360
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• 2018

Autophagy has been studied as a therapeutic strategy for cardiovascular diseases. However, insufficient studies have been reported concerning the influence of vascular smooth muscle cells (VSMCs) through autophagy regulation. The aim of the present study was to determine the effects of VSMCs on the regulation of autophagy under in vitro conditions similar to vascular status of the equipped micro-tubule target agent-eluting stent and increased release of platelet-derived growth factor-BB (PDGF-BB). Cell viability and proliferation were measured using MTT and cell counting assays. Immunofluorescence using an $anti-{\alpha}-tubulin$ antibody was performed to determine microtubule dynamic formation. Cell apoptosis was measured by cleavage of caspase-3 using western blot analysis, and by nuclear fragmentation using a fluorescence assay. Autophagy activity was assessed by microtubule-associated protein light chain 3-II (LC-II) using western blot analysis. Levels of intracellular reactive oxygen species (ROS) were measured using $H_2DCFDA$. The proliferation and viability of VSMCs were inhibited by microtubule regulation. Additionally, microtubule-regulated and PDGF-BB-stimulated VSMCs increased the cleavage of caspase-3 more than only the microtubule-regulated condition, similar to that of LC3-II, implying autophagy. Inhibitory autophagy of microtubule-regulated and PDGF-BB-stimulated VSMCs resulted in low viability. However, enhancement of autophagy maintained survival through the reduction of ROS. These results suggest that the apoptosis of conditioned VSMCs is decreased by the blocking generation of ROS via the promotion of autophagy, and proliferation is also inhibited. Thus, promoting autophagy as a therapeutic target for vascular restenosis and atherosclerosis may be a good strategy.

• Archives of Pharmacal Research
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• v.29 no.1
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• pp.67-72
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• 2006

The abnormal proliferation of aortic vascular smooth muscle cells (VSMCs) plays a central role in the pathogenesis of atherosclerosis and restenosis after angioplasty and possibly also in the development of hypertension. The present study was designed to examine the inhibitory effects and the mechanism of luteolin 7-glucoside (L7G) on the platelet-derived growth factor (PDGF)-BB-induced proliferation of VSMCs. L7G significantly inhibited the PDGF-BB-induced proliferation and the DNA synthesis of the VSMCs in a concentration-dependent manner. Pre-incubation of the VSMCs with L7G significantly inhibited the PDGF-BB-induced extracellular signal-regulated kinase 1/2 (ERK1/2), Akt and the phospholipase C $(PLC)-{\gamma}1$ activation. However, L7G had almost no affect on the phosphorylation of $PDGF-{\beta}$ receptor tyrosine kinase, which was induced by PDGF-BB. These results suggest that L7G inhibits the PDGF-BB-induced proliferation of VSMCs via the blocking of $(PLC)-{\gamma}1$, Akt, and ERK1/2 phosphorylation.