• BMB Reports
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• v.41 no.2
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• pp.164-169
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• 2008

The tumor suppressor gene p53 regulates apoptotic cell death and the cell cycle. In this study, we investigated the role of p53 in nitric oxide (NO)-induced apoptosis in vascular smooth muscle cells (VSMCs). We found that the NO donor S-nitroso-N-acetyl-penicillamine (SNAP) increased apoptotic cell death in p53-deficient VSMCs compared with wild-type cells. The heme oxygen-ase (HO) inhibitor tin protoporphyrin IX reduced the resistance of wild-type VSMCs to SNAP-induced cell death. SNAP promoted HO-1 expression in both cell types. HO-2 protein was increased only in wild-type VSMCs following SNAP treatment; however, similar levels of HO-2 mRNA were detected in both cell types. SNAP significantly increased the levels of non-heme-iron and dinitrosyl iron-sulfur clusters in wild-type VSMCs compared with p53-deficient VSMCs. Moreover, pretreatment with FeSO4 and the carbon monoxide donor CORM-2, but not biliverdin, significantly protected p53-deficient cells from SNAP-induced cell death compared with normal cells. These results suggest that wild-type VSMCs are more resistant to NO-mediated apoptosis than p53-deficient VSMCs through p53-dependent up-regulation of HO-2.

• The Korean Journal of Physiology and Pharmacology
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• v.19 no.5
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• pp.421-426
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• 2015

The increased potential for vascular smooth muscle cell (VSMC) growth is a key abnormality in the development of atherosclerosis and post-angioplasty restenosis. Abnormally high activity of platelet-derived growth factor (PDGF) is believed to play a central role in the etiology of these pathophysiological situations. Here, we investigated the anti-proliferative effects and possible mechanism(s) of murrayafoline A, a carbazole alkaloid isolated from Glycosmis stenocarpa Guillamin (Rutaceae), on PDGF-BB-stimulated VSMCs. Murrayafoline A inhibited the PDGF-BB-stimulated proliferation of VSMCs in a concentration-dependent manner, as measured using a non-radioactive colorimetric WST-1 assay and direct cell counting. Furthermore, murrayafoline A suppressed the PDGF-BB-stimulated progression through $G_0/G_1$ to S phase of the cell cycle, as measured by [$^3H$]-thymidine incorporation assay and cell cycle progression analysis. This anti-proliferative action of murrayafoline A, arresting cell cycle progression at $G_0/G_1$ phase in PDGF-BB-stimulated VSMCs, was mediated via down-regulation of the expression of cyclin D1, cyclin E, cyclin-dependent kinase (CDK)2, CDK4, and proliferating cell nuclear antigen (PCNA), and the phosphorylation of retinoblastoma protein (pRb). These results indicate that murrayafoline A may be useful in preventing the progression of vascular complications such as restenosis after percutaneous transluminal coronary angioplasty and atherosclerosis.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.5
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• pp.1060-1065
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• 2002

LC20 phosphorylation and PKC α play an important role in modulation of contractile activity of smooth muscle. Besides, myosin phosphatase is also related with smooth muscle contraction in signaling pathways. We previously demonstrated that Crataegi Fructus inhibited phenylephrine-induced contraction and which might be implicated in nitrite formation(Son et al., 2002). In this study, we investigated the effects of butanol fraction of Crataegi Fructus(BFFC) on the localization of α-protein kinease C(PKC α) and myosin phosphatase subnits(MPs) in freshly isolated single ferret potal vein cells, and phosphorylation of LC20 during phenylephrine stimulation. In PKC α and MPs localization, BFFC blocked its translocation from the cytosol to the cell membrane by treatment of phenylephrine. BFFC have also dephosphorylated LC20 phosphorylation by phenylephrine stimulation under basal level, but no significant. These results indicate that the relaxation effect of BFFC is associated with inhibition of PKC α activation and MPs dissociation, and thus myosin phosphatase activity may be increased.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.6
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• pp.1629-1635
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• 2006

The migration of vascular smooth muscle cells (VSMC) and the production of matrix metallopreteinases-9 (MMP-9) may play a key role in the development of atherosclerosis. In this study, we have more extensively investigated the inhibitory effect of UR on MMP-9 activity and TNF-${\alpha}$ induced human aortic smooth muscle cells (HASMC) migration. The result from gelatin zymography showed that UR inhibited MMP-9 activity in a dose-dependent manner (IC50 = 55 g/ml). In addition, UR strongly inhibited the migration of HASMC induced by TNF-treatment (IC50 = 125 g/ml), although it has very low cytotoxic effect on HASMC (IC50 > 500 g/ml). These results suggest that UR is a potential anti-atherosclerotic agent through inhibition of MMP-9 activity and VSMC migration.

• YAKHAK HOEJI
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• v.51 no.2
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• pp.150-156
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• 2007

Some flavonoids have spasmolytic activities in various smooth muscles, but structure-activity relationships on their spasmolytic activity and its mechanism are unclear. In this study, effects of flavones (flavone and apigenin) and flavonols (quercetin and rutin) on the rat ileal smooth muscle contraction were studied in vitro and in vitro. In the electric stimulation-induced contraction, all of four flavonoids inhibited concentration-dependently the rat ileal smooth muscle contraction induced by electric stimulation (10 mV, 0.1 cps, 0.1 msec duration), IC$_{50}$ of quercetin, apigenin, flavone and rutin were 0.98${\times}$10$^{-5}$, 1.20${\times}$10$^{-5}$, 1.55${\times}$10$^{-5}$ and 1.85${\times}$10$^{-5}$ M, respectively. Flavonoids at a concentration of 2${\times}$10$^{-5}$ M also significantly inhibited the anaphylactic contraction and decreased concentration-dependently the mast cell degranulation by anaphylactic reaction, IC$_{50}$ of quercetin, apigenin, flavone and rutin were 4.0${\times}$10$^{-5}$, 7.5${\times}$10$^{-5}$, 8.0${\times}$10$^{-5}$ and 9.5${\times}$10$^{-5}$ M, respectively. These results indicated that flavones and flavonols inhibited the rat ileal smooth muscle contraction induced by electric stimulation because of their antagonism against acetylcholine and have spasmolytic activities on anaphylactic contraction which may be due to their mast cell-stabilizing activities. Furthermore, double bond of C$_{2,3}$ in benzene ring of flavonoids may be important in the their antispasmodic activities on the rat ileal smooth muscle contraction induced by electric stimulation and anaphylactic reaction.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.5
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• pp.974-979
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• 2009

Proliferation of vascular smooth muscle cell(VSMC) is one of the key features in onset of atherosclerosis and restenosis after vascular surgery such as stent implant. Atherosclerotic plaques are usually composed of collagen, elatsin and smooth muscle cells. Release of matrix metalloproteinases(MMPs) is considered to have correlation with development of atherosclerotic plaques. Based on the hypothesis that MMP inhibition would be helpful in the treatment of atherosclerosis, we investigated inhibition of MMP activity and migration of TNF-$\alpha$-induced human aortic smooth muscle cell(HASMC) by Cinnamomi Ramulus(CC). The result from gelatin zymography showed that CC inhibited MMP-9 activity in a dose-dependent manner. In addition, CC considerably inhibited the migration of HASMC induced by TNF-$\alpha$, while it showed little cytotoxic effect on HASMC. These results suggest that CC can be a potential anti-atherosclerotic agent through inhibition of MMP-9 activity and SMC migration.

• Journal of Physiology & Pathology in Korean Medicine
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• v.29 no.6
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• pp.485-491
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• 2015

This study was aimed to investigate the relaxation effects of Eucomiae Cortex (EC) extract in isolated rabbit corpus cavernosum smooth muscle and its mechanism. To evaluate the relaxation of EC extract in rabbit corpus cavernosum, EC extract was treated in corporal strips which were precontracted with phenylephrine(PE). To study its mechanism, Nω-nitro-L-arginine (L-NNA) was pretreated after infuse of EC extract and compared with non-treated. In calcium chloride (Ca²⁺) -free krebs solution, EC extract and Ca²⁺ 1 mM were infused by turns after Ca²⁺ 1 mM was treated into corporal strips contracted by PE. Cell ability, nitric oxide (NO) and epithelial nitric oxide synthase (eNOS) on human umbilical vein endothelial cell (HUVEC) were measured by MTT assay, Griess reagent system and histochemical, immunohistochemical methods. EC extract showed a significant relaxation effects on the corporal strips, this effects were inhibited by pretreatment of L-NNA. EC extract inhibited the increase of contraction by Ca²⁺ influx in Ca²⁺-free krebs solution, and eNOS positive reaction in corpus cavernosum, NO production in HUVEC increased by treatment of EC extract. These result suggest that the relaxation effects of EC extract in isolated corpus cavernosum smooth muscle are involved in increase of eNOS and NO production, blocking of extracellular Ca²⁺ influx.

• 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.

• Journal of Marine Bioscience and Biotechnology
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• v.10 no.2
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• pp.53-61
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• 2018

Sargassum fulvellum (gulfweed) is a widespread seaweed in the coastal areas of northeast Asia. In the present study, we identified the phenolic compounds present in aqueous and ethanolic extracts of S. fulvellum and evaluated their antioxidative properties and their abilities to block cell proliferation using in vitro assays: antioxidant activity was assessed by using a DPPH assay and superoxide anion scavenging activity, anti-tyrosinase activity, and anti-proliferative activity were assessed using MTT and lactate dehydrogenase [LDH] assays in vascular smooth muscle cells. The hot-water ($65^{\circ}C$) extract had a higher phenol content than the ethanolic extract. The hot-water extract showed a statistically significant increase in free radical scavenging activity and a greater ability to reduce proliferation of vascular smooth muscle cells stimulated with platelet-derived growth factor-BB. Taken together, hot-water extracts of S. fulvellum may be an important source of antioxidative and antiproliferative agents.

• 대한약리학회:학술대회논문집
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• 2006.10a
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• pp.72-72
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• 2006