• Archives of Reconstructive Microsurgery
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• 제14권2호
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• pp.85-94
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• 2005

Purpose: This study was to evaluate the effect of ${\alpha}-lipoic$ acid, a potent free radical scavenger, on the expression of active form of extracellular signal-regulated kinase (pERK1/2) proteins from hindlimb muscles of rats following ischemia-reperfusion injury. Material and methods: 64 health, $280{\sim}350\;g$ weighted Sprague-Dawley male rats were used. In order to make a muscle flap, the gastrocnemius (GC) and soleus (SOL) muscles were dissected and elevated. The popliteal artery was occluded for 4hours and reperfused for 10 minutes, 30 minutes, 1 hour, 2 hours and 4 hours, respectively. Results: The ischemia by occlusion of the popliteal artery itself caused a minimal change in expression of phosphorylated form of proteins observed in hindlimb muscle. In contrast, after 4 hours of ischemia, immunoreactivity for pERK1/2 in the GC muscle showed dual peaks at 10 minutes and 4 hours after reperfusion. In ${\alpha}-lipoic$ acid treated group, the expression of pERK1/2 was increased significantly compared to I/R-only group. Conclusion: These results suggest that ${\alpha}-lipoic$ acid may protect I/R injury of the skeletal muscle through free radical scavening and activation of intracellular pERK1/2 expression.

• 생명과학회지
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• 제25권5호
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• pp.585-593
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• 2015

Stress fiber (SF) 변화는 세포외부의 결합인자와 세포 수용체와 결합후 리모델링을 위해 액틴골격에 신호를 전달하며 일어난다. 이 연관은 결합장소에서 기계적 활동과 신호전달활동을 조절하는 다양한 스케폴드들과 신호 전달자에 의해 매게된다. Heterotrimeric transmembrane lymphotoxin α1β2 (LTα1β2)는 용해성 homotrimeric LT α를 포함하는 tumor necrosis factor (TNF) 계로 림프조직을 구성하는데 중요한 역할을 한다. LTα1β2와 LTβR의 결합은 fibroblastic reticular cell (FRC)에서 신호전달을 촉발한다. Agonistic anti-LTβR antibody 단독 혹은 LTα 그리고 TNFα의 조합으로 LTβR 자극은 세포의 액틴과 형태적 변화를 보았다. Agonistic anti-LTβR antibody의 FRC에서 작용을 통한 세포골격 재배열이 myosin과의 관련성을 확인하기위해 myosin light chain kinase (MLCK)의 저해제인 ML-7과 myosin light chains (MLC)와 myosin phosphatase target subunit 1 (MYPT1)의 인산화에 대한 효과를 확인하였다. MLCK 저해는 액틴 세포골격 재배열과 세포형태 변화를 유도하였다. 또한, MLC와 MYPT1인산화가 LTβR 자극에 의해 줄어드는 것을 확인하였다. DNA chip 분석은 myosin and actin 구성선분이 전사체 수준에서도 줄어드는 것을 보였다. 결론적으로 LTβR 자극은 FRC에서 SF변화는 myosin과 관련되어 있다는 것을 제시한다.

• BMB Reports
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• 제45권11호
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• pp.629-634
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• 2012

The human glycoprotein, stanniocalcin 2 (STC2) plays multiple roles in several tumor types, however, its function and clinical significance in hepatocellular carcinoma (HCC) remain unclear. In this study, we detected STC2 expression by quantitative real-time PCR and found STC2 was upregulated in HCC tissues, correlated with tumor size and multiplicity of HCC. Ectopic expression of STC2 markedly promoted HCC cell proliferation and colony formation, while silencing of endogenous STC2 resulted in a reduced cell growth by cell cycle delay in G0/G1 phase. Western blot analysis demonstrated that STC2 could regulate the expression of cyclin D1 and activate extracellular signal-regulated kinase 1/2 (ERK1/2) in a dominant-positive manner. Transwell chamber assay also indicated altered patterns of STC2 expression had an important effect on cell migration. Our findings suggest that STC2 functions as a potential oncoprotein in the development and progression of HCC as well as a promising molecular target for HCC therapy.

• 한국약용작물학회지
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• 제19권5호
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• pp.373-379
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• 2011

Paeoniae Radix Rubra is a preparation consisting of desiccated roots of Paeonia lactiflora PALL (belonging to Ranunculaceae). Paeoniae Radix Rubra is used as a medicinal herb in Asian countries to treat many diseases. Ethanol- or water-based extracts of Paeoniae Radix Rubra were prepared and tested on RAW 264.7 cells, a murine macrophage cell line. The expression of some pro-inflammatory proteins, including inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), extracellular signal-regulated kinase 1/2 (ERK1/2) and phosphorylated ERK1/2 was detected by Western blot analyses, while PGE2 expression was quantified by ELISA. Both the water and ethanol extracts of Paeoniae Radix Rubra suppressed LPS-induced nitric oxide (NO) production and exhibited cell toxicity in accordance with increased NO production. Also, both extracts reduced the expression of COX-2 and iNOS, and inhibited phosphorylation of ERK1/2 in LPS-stimulated RAW 264.7 cells. Extracts prepared from Paeoniae Radix Rubra contain anti-inflammatory agents that inhibit the iNOS and MAPK pathways.

• 대한후두음성언어의학회지
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• 제32권1호
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• pp.15-23
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• 2021

Background and Objectives During speech, the vocal folds oscillate at frequencies ranging from 100-200 Hz with amplitudes of a few millimeters. Mechanical stimulation is an essential factor which affects metabolism of human vocal folds. The effect of mechanical vibration on the cellular response in the human vocal fold fibroblasts cells (hVFFs) was evaluated. Materials and Method We created a culture systemic device capable of generating vibratory stimulations at human phonation frequencies. To establish optimal cell culture condition, cellular proliferation and viability assay was examined. Quantitative real time polymerase chain reaction was used to assess extracellular matrix (ECM) related and growth factors expression on response to changes in vibratory frequency and amplitude. Western blot was used to investigate ECM and inflammation-related transcription factor activation and its related cellular signaling transduction pathway. Results The cell viability was stable with vibratory stimulation within 24 h. A statistically significant increase of ECM genes (collagen type I alpha 1 and collagen type I alpha 2) and growth factor [transforming growth factor β1 (TGF-β1) and fibroblast growth factor 1 (FGF-1)] observe under the experimental conditions. Vibratory stimulation induced transcriptional activation of NF-κB by phosphorylation of p65 subunit through cellular Mitogen-activated protein kinases activation by extracellular signal regulated kinase and p38 mitogen-activated protein kinases (MAPKs) phosphorylation on hVFFs. Conclusion This study confirmed enhancing synthesis of collagen, TGF-β1 and FGF was testified by vibratory stimulation on hVFFs. This mechanism is thought to be due to the activation of NF-κB and MAPKs. Taken together, these results demonstrate that vibratory bioreactor may be a suitable alternative to hVFFs for studying vocal folds cellular response to vibratory vocalization.

• Nutrition Research and Practice
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• 제9권3호
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• pp.256-261
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• 2015

BACKGROUND/OBJECTIVES: Yacon (Samallanthus sonchifolius), a common edible plant grown throughout the world, is well known for its antidiabetic properties. It is also known to have several other pharmacological properties including anti-inflammatory, anti-oxidant, anti-allergic, and anti-cancer effects. To date, the effect of yacon on gliomas has not been studied. In this study, we investigated the effects of yacon on the migration and proliferation of C6 glioma cells stimulated by fetal bovine serum (FBS). MATERIALS/METHODS: Cell growth and proliferation were determined by evaluating cell viability using an EZ-Cytox Cell Viability Assay Kit. FBS-induced migration of C6 glioma cells was evaluated by performing the scratch wound healing assay and the Boyden chamber assay. We also used western blot analysis to determine the expression levels of extracellular signal-regulated kinase 1/2 (ERK1/2), a major regulator of migration and proliferation of glioma cells. Matrix metallopeptidase (MMP) 9 and TIMP-1 levels were measured by performing reverse transcription PCR. RESULTS: Yacon ($300{\mu}g/mL$) reduced both the FBS-induced proliferation of C6 glioma cells and the dose-dependent migration of the FBS-stimulated C6 cells. FBS-stimulated C6 glioma cells treated with yacon (200 and $300{\mu}g/mL$) showed reduced phosphorylation of ERK1/2 and inhibition of MMP 9 expression compared to those shown by the untreated FBS-stimulated C6 cells. In contrast, yacon (200 and $300{\mu}g/mL$) induced TIMP-1 expression. CONCLUSIONS: On the basis of these results, we suggest that yacon may exert an anti-cancer effect on FBS-stimulated C6 glioma cells by inhibiting their proliferation and migration. The most likely mechanism for this is down-regulation of ERK1/2 and MMP9 and up-regulation of TIMP-1 expression levels.

• Journal of Korean Neurosurgical Society
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• 제43권2호
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• pp.97-104
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• 2008

Objective: Transient receptor potential vanilloid subfamily type 1 (TRPV1), a most specific marker of the nociceptive primary afferent, is expressed in peptidergic and non-peptidergic primary afferents innervating skin and viscera. However, its expression in sensory fibers to skeletal muscle is not well known. In this study, we studied the neurochemical characteristics of TRPV1-positive primary afferents to skeletal muscles. Methods: Sprague-Dawley rats were injected with total $20{\mu}l$ of 1% fast blue (FB) into the gastrocnemius and erector spinae muscle and animals were perfused 4 days after injection. FB-positive cells were traced in the L4-L5 (for gastrocnemius muscle) and L2-L4 (for erector spinae muscle) dorsal root ganglia. The neurochemical characteristics of the muscle afferents were studied with multiple immunofluorescence with TRPV1, calcitonin gene-related peptide (CGRP) and $P2X_3$. To identify spinal neurons responding to noxious stimulus to the skeletal muscle, 10% acetic acids were injected into the gastrocnemius and erector spinae muscles and expression of phospho extracellular signal-regulated kinase (pERK) in spinal cords were identified with immunohistochemical method. Results: TRPVl was expressed in about 49% of muscle afferents traced from gastrocnemius and 40% of erector spinae. Sixty-five to 60% of TRPV1-positive muscles afferents also expressed CGRP. In contrast, expression of $P2X_3$ immnoreaction in TRPV1-positive muscle afferents were about 20%. TRPV1-positive primary afferents were contacted with spinal neurons expressing pERK after injection of acetic acid into the muscles. Conclusion: It is consequently suggested that nociception from skeletal muscles are mediated by TRPV1-positive primary afferents and majority of them are also peptidergic.

• The Korean Journal of Physiology and Pharmacology
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• 제21권1호
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• pp.117-124
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• 2017

The present study aimed to show that pro-inflammatory cytokines [tumor necrosis factor (TNF)-${\alpha}$, interferon (IFN)-${\gamma}$, and interleukin (IL)-$1{\beta}$] synergistically induce the production of nitric oxide (NO) production in mouse mesangial cells, which play an important role in inflammatory glomerular injury. We also found that co-treatment with cytokines at low doses (TNF-${\alpha}$; 5 ng/ml, IFN-${\gamma}$; 5 ng/ml, and IL-$1{\beta}$; 1.25 U/ml) synergistically induced NO production, whereas treatment with each cytokine alone did not increase NO production at doses up to 100 ng/ml or 50 U/ml. Silymarin, a polyphenolic flavonoid isolated from milk thistle (Silybum marianum), attenuates cytokine mixture (TNF-${\alpha}$, IFN-${\gamma}$, and IL-$1{\beta}$)-induced NO production. Western blot and RT-PCR analyses showed that silymarin inhibits inducible nitric oxide synthase (iNOS) expression in a dose-dependent manner. Silymarin also inhibited extracellular signal-regulated protein kinase-1 and -2 (ERK1/2) phosphorylation. Collectively, we have demonstrated that silymarin inhibits NO production in mouse mesangial cells, and may act as a useful anti-inflammatory agent.

• KSBB Journal
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• 제28권2호
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• pp.137-145
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• 2013

In order to develop new skin whitening agents, we prepared the $CH_2Cl_2$ layer (NGC) and BuOH layer (NGB) of 75% EtOH extract of the Nelumbinis nucifera Gaertner. We measured their tyrosinase inhibitory activity in vitro and melanin synthesis inhibitory activity in B16-F1 melanoma cells. They did not show inhibitory activity against mushroom tyrosinase but showed melanin synthesis inhibitory activity in a dose-dependent manner. In a melanin synthesis inhibition assay, NGC and NGB suppressed melanin production up to 52% and 46% at a concentration of $100{\mu}g/mL$, respectively. To elucidate the mechanism of the inhibitory effects of NGC and NGB on melanogenesis, we measured the expression of melanogenesis-related proteins by western blot assay. As a result, NGC suppressed the expression of tyrosinase, tyrosinase related protein 1 (TRP-1), tyrosinase related protein 2 (TRP-2), phosphorylated cAMP responsive element binding (p-CREB) protein, and microphthalmia associated transcription factor (MITF). And NGB inhibited the protein expression of tyrosinase and MITF, but had no significant effect on TRP-1, TRP-2, and p-CREB expression. Moreover, NGB increased the expression of phosphorylated extracellular signal-regulated kinase (p-ERK). In addition, we examined the inhibitory effect on the glycosylation of tyrosinase. As a result, NGC and NGB inhibited the activity of ${\alpha}$-glucosidase in vitro and the glycosylation of tyrosinase in B16-F1 melanoma cells. From these results, we concluded that NGC and NGB could be used as active ingredients for skin whitening.

• The Korean Journal of Physiology and Pharmacology
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• 제17권4호
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• pp.315-320
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• 2013

Here, we show that radicicol, a fungal antibiotic, resulted in marked inhibition of inducible nitric oxide synthase (iNOS) transcription by the pancreatic beta cell line MIN6N8a in response to cytokine mixture (CM: TNF-${\alpha}$, IFN-${\gamma}$, and IL-$1{\beta}$). Treatment of MIN6N8a cells with radicicol inhibited CM-stimulated activation of NF-${\kappa}B$/Rel, which plays a critical role in iNOS transcription, in a dose-related manner. Nitrite production in the presence of PD98059, a specific inhibitor of the extracellular signal-regulated protein kinase-1 and 2 (ERK1/2) pathway, was dramatically diminished, suggesting that the ERK1/2 pathway is involved in CM-induced iNOS expression. In contrast, SB203580, a specific inhibitor of p38, had no effect on nitrite generation. Collectively, this series of experiments indicates that radicicol inhibits iNOS gene expression by blocking ERK1/2 signaling. Due to the critical role that NO release plays in mediating destruction of pancreatic beta cells, the inhibitory effects of radicicol on iNOS expression suggest that radicicol may represent a useful anti-diabetic activity.