• The Korean Journal of Physiology
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• 제23권1호
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• pp.1-12
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• 1989

• 대한동의생리학회:학술대회논문집
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• 대한동의생리학회 2004년도 하계학술대회 및 임시정기총회
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• pp.6-6
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• 2004

• 대한약학회:학술대회논문집
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• 대한약학회 2001년도 Proceedings of International Convention of the Pharmaceutical Society of Korea
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• pp.142.1-142.1
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• 2001

• The Korean Journal of Physiology and Pharmacology
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• 제24권1호
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• pp.69-79
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• 2020

Aging is one of the risk factors for the development of cardiovascular diseases. During the progression of cellular senescence, cells enter a state of irreversible growth arrest and display resistance to apoptosis. As a flavonoid, quercetin induces apoptosis in various cells. Accordingly, we investigated the relationship between quercetin-induced apoptosis and the inhibition of cellular senescence, and determined the mechanism of oxidative stress-induced vascular smooth muscle cell (VSMC) senescence. In cultured VSMCs, hydrogen peroxide (H₂O₂) dose-dependently induced senescence, which was associated with increased numbers of senescence-associated β-galactosidase-positive cells, decreased expression of SMP30, and activation of p53-p21 and p16 pathways. Along with senescence, expression of the anti-apoptotic protein Bcl-2 was observed to increase and the levels of proteins related to the apoptosis pathway were observed to decrease. Quercetin induced apoptosis through the activation of AMP-activated protein kinase. This action led to the alleviation of oxidative stress-induced VSMC senescence. Furthermore, the inhibition of AMPK activation with compound C and siRNA inhibited apoptosis and aggravated VSMC senescence by reversing p53-p21 and p16 pathways. These results suggest that senescent VSMCs are resistant to apoptosis and quercetin-induced apoptosis attenuated the oxidative stress-induced senescence through activation of AMPK. Therefore, induction of apoptosis by polyphenols such as quercetin may be worthy of attention for its anti-aging effects.

• BMB Reports
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• 제53권4호
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• pp.206-211
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• 2020

Vascular smooth muscle cells (VSMCs) are a unique cell type that has unusual plasticity controlled by environmental stimuli. As an abnormal increase of VSMC proliferation is associated with various vascular diseases, tight regulation of VSMC phenotypes is essential for maintaining vascular homeostasis. Hypoxia is one environmental stress that stimulates VSMC proliferation. Emerging evidence has indicated that microRNAs (miRNAs) are critical regulators in the hypoxic responses of VSMCs. Therefore, we previously investigated miRNAs modulated by hypoxia in VSMCs and found that miR-1260b is one of the most upregulated miRNAs under hypoxia. However, the mechanism that underlies the regulation of VSMCs via miR-1260b in response to hypoxia has not been explored. Here we demonstrated that hypoxia-induced miR-1260b promotes VSMC proliferation. We also identified growth differentiation factor 11 (GDF11), a member of the TGF-β superfamily, as a novel target of miR-1260b. miR-1260b directly targets the 3'UTR of GDF11. Downregulation of GDF11 inhibited Smad signaling and consequently enhanced the proliferation of VSMCs. Our findings suggest that miR-1260b-mediated GDF11-Smad-dependent signaling is an essential regulatory mechanism in the proliferation of VSMCs, and this axis is modulated by hypoxia to promote abnormal VSMC proliferation. Therefore, our study unveils a novel function of miR-1260b in the pathological proliferation of VSMCs under hypoxia.

• 생명과학회지
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• 제17권1호
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• pp.45-50
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• 2007

세포 배양액에 tetracycline이 없는 경우 FADD를 발현하면서 사멸하는 평활근세포 (FADD-SMC)에서 분비하는 $TNF-\alpha$의 활성을 조사하였다. 배양액에 tetracycline이 없는 경우 FADD-SMC는 약 1000 pg/ml의 $TNF-\alpha$를 분비하였다. $TNF-\alpha$를 포함하는 배양액을 분리하고, 이 배양액을 정상세포에 처리한 결과 인산화한 p38 MAPK와 nuclear, factor, kappa B (NF-kB)의 활성이 증가하였다. 또한 이 배양액을 L929 세포에 처리하는 경우 세포독성이 발생하였다. NF-kB, p38 MAPK 그리고 L929 세포에 대찬 효과는 배양액에서 suluble TNF receptor를 이용하여 $TNF-\alpha$를 제거하는 경우 감소하였다.

• Molecules and Cells
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• 제19권1호
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• pp.60-66
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• 2005

Low density lipoproteins (LDL) play important roles in the pathogenesis of atherosclerosis. Diabetes is associated with accelerated atherosclerosis leading to cardiovascular disease in diabetic patients. Although LDL stimulates the proliferation of arterial smooth muscle cells (SMC), the mechanisms are not fully understood. We examined the effects of native LDL and glycated LDL on the extracellular signal-regulated kinase (ERK) pathway. Addition of native and glycated LDL to rat aorta SMCs (RASMCs) stimulated ERK phosphorylation. ERK phosphorylation was not affected by exposure to the $Ca^{2+}$ chelator BAPTA-AM but inhibition of protein kinase C (PKC) with GF109203X, inhibition of Src kinase with PP1 ($5{\mu}M$) and inhibition of phospholipase C (PLC) with U73122/U73343 ($5{\mu}M$) all reduced ERK phosphorylation in response to glycated LDL. In addition, pretreatment of the RASMCs with a cell-permeable mitogen-activated protein kinase kinase (MEK) inhibitor (PD98059, $5{\mu}M$) markedly decreased ERK phosphorylation in response to native and glycated LDL. These findings indicate that ERK phosphorylation in response to glycated LDL involves the activation of PKC, PLC, and MEK, but is independent of intracellular $Ca^{2+}$.

• 생명과학회지
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• 제22권12호
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• pp.1595-1599
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• 2012

혈관 증식 질환에서 세포주기 활성화와 진행은 중요한 치료 목적으로 사용된다. Luteolin는 glycosylated 형태로 샐러리, 후추, 들깨 잎 그리고 카밀레 차에 존재하며 항돌연변이, 항종양, 항산화 그리고 항염증을 나타낸다. 본 연구에서는 흰쥐 동맥으로부터 분리한 혈관평활근세포를 배양하여 소태아혈청으로 유도된 증식에서 luteolin 효과에 대해 조사했다. Luteolin이 5% 소태아혈청으로 유도된 흰쥐의 혈관평활근세포 증식과 DNA 합성을 5, 20 그리고 $50{\mu}M$에서 억제했다. 혈관평활근세포 증식을 각각 29.6, 50.8 그리고 83.1% 억제했고 DNA 합성은 각각 25.8, 57.6 그리고 81.0% 억제했다. 게다가, 유세포분석 결과 소태아혈청으로 유도된 혈관평활근세포의 세포주기는 luteolin에 의해 차단되었다. 이러한 결과는 세포독성에 의해서도 나타날 수 있기 때문에 WST-1 분석으로 세포독성을 확인한 결과 세포독성 없이 세포주기를 차단하는 효과임을 확인했다. 이상의 결과들은 luteolin이 혈관스텐트와 동맥경화의 치료를 위한 의미있는 항증식 물질임을 보여준다.

• 대한의용생체공학회:의공학회지
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• 제29권1호
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• pp.52-58
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• 2008

The object of this study is to investigate the effects of intermittent cyclic stretching on the smooth muscle cells (SMCs) seeded onto aligned multi-layered fibrous scaffold. To make multi-layered fibrous scaffold, polyurethane (PU) and poly(ethylene oxide) (PEO) were electrospun alternatively, then were immersed into distilled water to extract PEO. Various types of scaffolds were fabricated depending on fiber directions, i.e., aligned or randomly oriented. The direction of stretching was either parallel or vertical to the fiber direction for the aligned scaffolds. The stretching was also applied to the randomly aligned scaffolds. The duration of stretching was 2 min with 15 min resting period. During the stretching, the maximum and minimum strain was adjusted to be 10 and 7%, respectively with the frequency of 1 Hz. The bioactivities of cells on the scaffolds were assessed by quantifying DNA, collagen, and glycosaminoglycan (GAG) levels. And the cell morphology was observed by staining F-actin. SMCs under parallel stretching to the fiber direction responded more positively than those in other conditions. From the results, we could explain the morphological effect of a substrate on cellular activities. In addition the synergistic effects of substrate and mechanical stimuli effects were confirmed.

• The Journal of Korean Physical Therapy
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• 제21권2호
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• pp.109-116
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• 2009

Purpose: $17\beta$-estradiol is the most active endogenous estrogen, which is related to favorable changes in the plasma lipid profile, to relaxation of the coronary vessels, and to a decrease in platelet aggregation and vascular smooth muscle cell migration. However, although the beneficial effect of estrogens on plasma lipoproteins (ie, lowering low-density lipoprotein and increasing high-density lipoprotein cholesterol) contributes to cardiovascular protection, it does not fully account for the protective effect, particularly in the application of physical therapy, including low frequency electrical stimulation. Methods: The aim of this study was to demonstrate the inhibition of stressors, such as endothelin-1 (ET-1), serotonin (5-hydroxytryptamine, 5-HT), prostaglandin $F2\alpha$ ($PGF2\alpha$), and a protein kinase C (PKC) activator 12-deoxyphorbol 13-isobutyrate (DPB), induced isometric tension by $17\beta$-estradiol in vascular smooth muscle strips, respectively. In addition, the effects of low frequency electrical stimulation at the meridian points (CV-3, -4, Ki-12, SP-6, LR-3, BL-25, -28, -32, -52) on the indirect antihypertensive effect were examined by monitoring the changes in the serum $17\beta$-estradiol concentration in healthy volunteers. Results: Isometric tension analysis showed that the responses of inhibited tension by $17\beta$-estradiol were similar to the same stressors in rat aortic smooth muscle strips. Furthermore, although the continued amplitude modulation (AM) type of electrical stimulation was not increased significantly by electrical stimulation, the current of the frequency modulation (FM) type of low frequency electrical stimulation increased the serum $17\beta$-estradiol concentration in normal volunteers. Conclusion: These results, in part, suggest that $17\beta$-estradiol has the capacity to supress stressor-induced muscle tension, and electrical stimulation, particularly current of the FM type, has a modulatory effect on the sex steroid hormones, particularly $17\beta$-estradiol, in healthy volunteers.