• 대한한의학회지
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• 제23권2호
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• pp.19-27
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• 2002

Objective : This study was designed to investigate the effect of Hyeolbuchukeo-tang (HCT) on NO production and the molecular mechanism of NO production modulated by HCT in the primary VSMC (vascular smooth muscle cells). Method : Primary VSMC was established from aorta and cultured VSMC used in this study. NO production of VSMC was assayed by Griess reagent and the expression of iNOS gene was assayed by Western, RT-PCR. Result : $TNF-{\gamma}$ induced NO production, but $IFN-{\gamma}$ or HCT alone did not induce NO production in cultured VSMC. However, $IFN-{\gamma}$ or HCT potentiated NO production in $TNF-{\gamma}-treated$ VSMC in a time- and dose-dependent manner. $TNF-{\gamma}$ induced the iNOS gene expression corresponding to NO production in $TNF-{\gamma}-treated$ VSMC. HCT potentiated NO production in $TNF-{\gamma}-treated$ VSMC by about 20%, but HCT did not increase the level of iNOS mRNA in $TNF-{\gamma}-treated$ VSMC. HCT slightly increased the level of iNOS protein in $TNF-{\gamma}-treated$ VSMC. Calcium ionophore A23187 decreased NO production in $TNF-{\gamma}-treated$ VSMC, but HCT attenuated the effect of A23187. Conclusion : As NO is deeply involved in the development of arteriosclerosis and dilation of blood vessels, drugs or chemicals modulating NO production in VSMC could be used for preventing and treating arteriosclerosis. Considering the effect of HCT on the modulation of NO production in VSMC, MCT has a potential capacity for preventing and treating diseases of the circulation system including arteriosclerosis.

• The Korean Journal of Physiology and Pharmacology
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• 제13권4호
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• pp.309-313
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• 2009

Spontaneous hypertensive rats (SHR) are an established model of genetic hypertension. Vascular smooth muscle cells (VSMC) from SHR proliferate faster than those of control rats (Wistar-Kyoto rats; WKY). We tested the hypothesis that induction of heme oxygenase (HO)-1 induced by aprotinin inhibits VSMC proliferation through cell cycle arrest in hypertensive rats. Aprotinin treatment inhibited VSMC proliferation in SHR more than in normotensive rats. These inhibitory effects were associated with cell cycle arrest in the G1 phase. Tin protoporphyrin IX (SnPPIX) reversed the anti-proliferative effect of aprotinin in VSMC from SHR. The level of cyclin D was higher in VSMC of SHR than those of WKY. Aprotinin treatment downregulated the cell cycle regulator, cyclin D, but upregulated the cyclin-dependent kinase inhibitor, p21, in VSMC of SHR. Aprotinin induced HO-1 in VSMC of SHR, but not in those of control rats. Furthermore, aprotinin-induced HO-1 inhibited VSMC proliferation of SHR. Consistently, VSMC proliferation in SHR was significantly inhibited by transfection with the HO-1 gene. These results indicate that induction of HO-1 by aprotinin inhibits VSMC proliferation through cell cycle arrest in hypertensive rats.

• Preventive Nutrition and Food Science
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• 제19권4호
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• pp.363-366
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• 2014

Zinc is considered to be involved in maintaining healthy vascular condition. Atherosclerotic calcification of vascular smooth muscle cells (VSMCs) occurs via the mechanism of cell death; therefore, cell viability is a critical factor for preventing VSMC calcification. In this study, we tested whether zinc affected VSMC viability under both normal physiological non-calcifying (0 mM P) and atherosclerotic calcifying conditions (3 and 5 mM P), since VSMC physiological characters change during the VSMC calcification process. The study results showed that an optimal zinc level ($15{\mu}M$) restored the decreased VSMC viability which was induced under low zinc levels (0 and $1{\mu}M$) and calcifying conditions (3 and 5 mM P) at 9 and 15 days culture. This zinc-protecting effect for VSMC viability is more prominent under atherosclerotic calcifying condition (3 and 5 mM P) than normal condition (0 mM P). Also, the increased VSMC viability was consistent with the decreased Ca and P accumulation in VSMC cell layers. The results suggested that zinc could be an effective biomineral for preventing VSMC calcification under atherosclerotic calcifying conditions.

• The Korean Journal of Physiology and Pharmacology
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• 제7권2호
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• pp.103-109
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• 2003

The cellular mechanisms that contribute to the acceleration of atherosclerosis in diabetes are poorly understood. Therefore, the potential mechanisms involved in the diabetes-dependent increase in vascular smooth muscle cell (VSMC) proliferation was investigated. Using primary culture of VSMC from streptozotocin-induced diabetic rat aorta, cell proliferation assay showed two-fold increase in cell number accompanied with enhanced superoxide generation compared to normal VSMC, 2 days after plating. Both the increased superoxide production and cell proliferation in diabetic VSMC were significantly attenuated by not only tiron (1 mM), a superoxide scavenger, but also by diphenyleneiodonium (DPI; $10{\mu}M$), an NAD(P)H oxidase inhibitor. NAD(P)H oxidase activity in diabetic VSMC was significantly higher than that in control cell, accompanied with increased mRNA expression of p22phox, a membrane subunit of oxidase. Furthermore, inhibition of p22phox expression by transfection of antisense p22phox oligonucleotides into diabetic VSMC resulted in a decrease in superoxide production, which was accompanied by a significant inhibition of cell proliferation. Based on these results, it is suggested that diabetes-associated increase in NAD(P)H oxidase activity via enhanced expression of p22phox contributes to augmented VSMC proliferation in diabetic rats.

• The Korean Journal of Physiology and Pharmacology
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• 제11권1호
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• pp.31-36
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• 2007

To elucidate a potential molecular link between diabetes and atherosclerosis, we investigated the role of Janus tyrosine kinase(JAK) for NAD(P)H oxidase-derived superoxide generation in the enhanced proliferative capacity of vascular smooth muscle cells(VSMC) of Otsuka Long-Evans Tokushima Fatty(OLETF) rat, an animal model of type 2 diabetes. An enhanced proliferative response to 10% fetal bovine serum(FBS) and superoxide generation with an increased NAD(P)H oxidase activity were observed in diabetic(OLETF) VSMC. Both the enhanced proliferation and superoxide generation in diabetic VSMC were significantly attenuated by AG490, JAK2 inhibitor, and PP2, Src kinase inhibitor. Tyrosine phosphorylation of proteins in diabetic VSMC, especially JAK2, was increased compared to control VSMC. Furthermore, the enhanced NAD(P)H oxidase activity in diabetic VSMC was significantly attenuated by AG490 in a dose-dependent manner. Together, these results indicate that the signal pathway which leads to diabetes-associated activation of Src kinase/JAK is critically involved in the diabetic VSMC proliferation through NAD(P)H oxidase activation and superoxide generation.

• 한국식물생명공학회:학술대회논문집
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• 한국식물생명공학회 2004년도 생명공학 실용화를 위한 비젼
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• pp.81-90
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• 2004

Sialic acid containing glycosphingolipids (gangliosides) have been implicated in the regulation of various biological phenomena such as atherosclerosis. Recent report suggeststhat exogenously supplied disialoganglioside (GD3) serves a dual role in vascular smooth muscle cells (VSMC) proliferation and apoptosis. However, the role of the GD3 synthase gene in VSMC responses has not yet been elucidated. To determine whether a ganglioside is able to modulate VSMC growth. the effect of overexpression of the GD3 synthase gene on DNA synthesis was examined. The results show that the overexpression of this gene has a potent inhibitory effect on DNA synthesis and ERK phosphorylation in cultured VSMC in the presence of PDGF. The suppression of the GD3 synthase gene was correlated with the down-regulation of cyclinE/CDK2. the up-regulation of the CDK inhibitor p21 and blocking of the p27 inhibition,whereas up-regulation of p53 as the result of GD3 synthase gene expression was not observed. Consistently, blockade of GD3 function with anti-GD3 antibody reversed VSMC proliferation and cell cycle proteins. The expression of the CD3 synthase gene also led to the inhibition of TNF--induced matrix metalloproteinase-9 (MMP-9) expression in VSMC as determined by zymography and immunoblot. Furthermore, GD3 synthase gene expression strongly decreased MMP-9 promoteractivlty in response to TNF-. This inhibition was characterized by the down-regulation of MMP-9,which was Iranscriptionally regulated at NF-B and activation protein-1 (AP-1) sites in the MMP-9promoter Finally, the overexpression of MMP-9 in GD3 synthase transfectant cells rescued VSMC proliferation. However MMP-2 overexpression was not affected the cell proliferation. These findings suggest that the fl13 synthase gene represents a physiological modulator of VSMC responses that may contribute to plaque instability in atherosclerosis.

• Preventive Nutrition and Food Science
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• 제18권2호
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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.

• 대한한의학회지
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• 제24권2호
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• pp.166-178
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• 2003

Objectives : Nitric oxide (NO) plays an important role in normal and pathophysiological cells as a messenger molecule, neurotransmitter, microbiological agent, or dilator of blood vessels and arteriosclerosis, respectively. This study was undertaken to understand the mechanism of NO production and effect of Hyeolbuchukeo-tang (Xiefuzhuyu-tang) on NO production in cultured vascular smooth muscle cell (VSMC). Methods and Results : VSMC was isolated from aorta and cultured. Cultured primary cells were identified as VSMC with anti--smooth muscle actin antibody. A large amount of NO was produced in cultured VSMC treated with $IFN-{\gamma}$ plus TNF in a time- and dose-dependent manner. $TNF-{\alpha}$ was a more efficient stimulator than $IFN-{\gamma}$ in NO production of cultured VSMC. iNOS protein wasdetected within 3 hrs and it increased up to 12 hrs in a time-dependent manner. However, accumulated NO in cytokine-treated VSMC was not detected within 3 hrs. NO production in cytokine-treated VSMC showed the dose- and time-dependent manner, and increased up to 48 hrs. The activated VSMC produced a large amount of NO (about 60 uM). Hyeolbuchukeo-tang (Xiefuzhuyu-tang) alone did not induceNO production, but it potentiated the effect of $TNF-{\alpha}$ on NO production and increased NO production by about 20%. Hyeolbuchukeo-tang (Xiefuzhuyu-tang) did not affect the transcriptional activity of iNOS gene, but increased the accumulation of iNOS. These results indicate that Hyeolbuchukeo-tang (Xiefuzhuyu-tang) could modulate the translational level of iNOS. PKC did not modulate NO production, but calcium ionophore A23187 decreased NO production. However, Hyeolbuchukeo-tang (Xiefuzhuyu-tang) elevated the decreased NO production in A23187-treated VSMC by modulating the stability of iNOS transcripts. Half-life of the synthesized transcripts appeared to have about 6 hrs. PDTC, an $NF-{\kappa}B$ inhibitor, blocked the accumulation of iNOS mRNA, indicating that $NF-{\kappa}B$ served as an important modulator in the transcriptional regulation of iNOS. As Hyeolbuchukeo-tang (Xiefuzhuyu-tang) potentiated the effect of the $TNF-{\alpha}$ on NO production but had no additional effect on PDTC-modulated NO production, it is suggested that Hyeolbuchukeo-tang (Xiefuzhuyu-tang) enhances the $TNF-{\alpha}-mediated$ NO production of VSMC by modulating the iNOS activity and the stability of iNOS transcripts in activated VSMC having the elevated intracellular calcium ion. Conclusions : This study suggests that Hyeolbuchukeo-tang (Xiefuzhuyu-tang) has a potential capacity for preventing and treating diseases of the circulation system, including arteriosclerosis.

• The Korean Journal of Physiology and Pharmacology
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• 제26권6호
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• pp.519-530
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• 2022

Recent research indicates that lactate promotes the switching of vascular smooth muscle cells (VSMCs) to a synthetic phenotype, which has been implicated in various vascular diseases. This study aimed to investigate the effects of lactate on the VSMC phenotype switch and the underlying mechanism. The CCK-8 method was used to assess cell viability. The microRNAs and mRNAs levels were evaluated using quantitative PCR. Targets of microRNA were predicted using online tools and confirmed using a luciferase reporter assay. We found that lactate promoted the switch of VSMCs to a synthetic phenotype, as evidenced by an increase in VSMC proliferation, mitochondrial activity, migration, and synthesis but a decrease in VSMC apoptosis. Lactate inhibited miR-23b expression in VSMCs, and miR-23b inhibited VSMC's switch to the synthetic phenotype. Lactate modulated the VSMC phenotype through downregulation of miR-23b expression, suggesting that overexpression of miR-23b using a miR-23b mimic attenuated the effects of lactate on VSMC phenotype modulation. Moreover, we discovered that SMAD family member 3 (SMAD3) was the target of miR-23b in regulating VSMC phenotype. Further findings suggested that lactate promotes VSMC switch to synthetic phenotype by targeting SMAD3 and downregulating miR-23b. These findings suggest that correcting the dysregulation of miR-23b/SMAD3 or lactate metabolism is a potential treatment for vascular diseases.

• The Korean Journal of Physiology and Pharmacology
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• 제10권3호
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• pp.161-165
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• 2006

NO and cyclooxygenase-2 (COX-2) are contributes to vascular inflammation induced by various stimulation. The mechanism, which explains a linkage between NO and COX-2, could be of importance in promoting pathophysiological conditions of vessel. We investigated the effects of NO donors on the COX-l and COX-2 mRNA/protein expression, as well as the nitrite production in culture medium of vascular smooth muscle cell (VSMC). VSMC was primarily cultured from thoracic aorta of rat. In this experiments, COX-l and COX-2 mRNA/protein expressions were analysed and nitrite productions were investigated using Griess reagent. VSMC did not express COX-2 protein in basal condition (Nonlipopolysaccharide (LPS) stimulated). In LPS-stimulated experiments, after 3 hours of NO donor pretreatment, LPS $10{\mu}g/ml$ was treated for 24 hours. COX-l protein expressions were unchanged by SNP and NOR-3. NOR-3 significantly increased COX-2 mRNA/protein expression under LPS stimulation. In contrast, SNP did not increase COX-2 mRNA/protein expression under LPS stimulation. Nitrite production was higher in NOR-3 treatment than SNP treatment under LPS stimulation. These results suggest that the expression of COX-2 in VSMC is regulated by NOR-3, COX-2 expressions were depending on the types of NO donor and LPS stimulation in VSMC.