• Animal cells and systems
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• 제8권2호
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• pp.125-133
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• 2004

We have extended our previous work that cross-linking CD4 molecules using specific MAb induced antigen nonspecific, MHC unrestricted killing of virally infected target cells by CD$4^+$We have extended our previous work that cross-linking CD$4^+$ molecules using specific MAb induced antigen nonspecific, MHC unrestricted killing of virally infected target cells by CD$4^+$ T cells. The killing activity of antibody activated CD$4^+$T cells was completely blocked by herbimycin A, a protein tyrosine kinase (PTK) inhibitor, but not by bisindolylamaleimide, a protein kinase C (PKC) inhibitor. Herbimycin A treated human or bovine peripheral blood CD$4^+$T cells lacked PTK activity and failed to kill virally infected target cells even after cross-linking of CD4 molecules. The CD$4^+$cross-linking failed to induce effector cell proliferation or the transcription of TNF${\beta}$ Upregulation of TNF${\beta}$ was induced by incubating the antibody activated effector cells with BHV-1 infected D17 target cells for 10 h. Anti-TNF${\beta}$ antibody partially abolished (13-44%) the direct effector cell-mediated antiviral cytotoxicity. However, this antibody neutralized 70 to 100% of antiviral activity of effector and target cell culture supernatants against BHV-1 infected D17 cells. The inhibition level of the antiviral activity by the antibody was dependent on the effector and target cell ratio. These results support the hypothesis that increased p$56^ICK enzyme activity in effector cells transduces a signal critical for effector cell recognition of viral glycoproteins expressed on the target cells. Following target cell recognition, lytic cytokines known to participate in target cell killing were produced. A better understanding of the killing activity displayed by CD$4^+$T lymphocytes following surface receptor cross-linking will provide insight into the mechanisms of cytotoxic activity directed toward virally-infected cells.T cells. The killing activity of antibody activated CD$4^+$T cells was completely blocked by herbimycin A, a protein tyrosine kinase (PTK) inhibitor, but not by bisindolylamaleimide, a protein kinase C (PKC) inhibitor. Herbimycin A treated human or bovine peripheral blood CD4T cells lacked PTK activity and failed to kill virally infected target cells even after cross-linking of CD4molecules. The CD4 cross-linking failed to induce effector cell proliferation or the transcription of TNF$\beta$. Upregulation of TNF$\beta$ was induced by incubating the antibody activated effector cells with BHV-1 infected D17 target cells for 10 h. Anti-TNF$\beta$ antibody partially abolished (13-44%) the direct effector cell-mediated antiviral cytotoxicity. However, this antibody neutralized 70 to 100% of antiviral activity of effector and target cell culture supernatants against BHV-1 infected D17 cells. The inhibition level of the antiviral activity by the antibody was dependent on the effector and target cell ratio. These results support the hypothesis that increased $56^ICK enzyme activity in effector cells transduces a signal critical for effector cell recognition of viral glycoproteins expressed on the target cells. Following target cell recognition, lytic cytokines known to participate in target cell killing were produced. A better understanding of the killing activity displayed by CD$4^+$T lymphocytes following surface receptor cross-linking will provide insight into the mechanisms of cytotoxic activity directed toward virally-infected cells.

• 동의생리병리학회지
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• 제23권3호
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• pp.619-630
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• 2009

To investigate the hair growth activity of fractions and extract of Arisaematis Rhizoma in the hair removed skin of normal and spontaneous alopecia areata model in C57B/6N mice. These experiments were performed with the macroscopic, microscopic, immunohistochemical(VEGF, c-kit, PKC-${\alpha}$, TGF and FGF) and RT-PCR(TGF-${\beta}$, IGF, prolactin and placenta lactogen) methods. The results were as follows: Macroscopic observation after topical application of vehicle, 50% EtOH as control and extract of Arisaematis Rhizoma to the hair removed skin of C57BL/6N mice on the 9th, 11th and 15th day. Extensive hair growth activity was observed in treated group with extract of Arisaematis Rhizoma on the 9th, 11th and 15th day. In Arisaematis Rhizoma extracts treated group, hair follicles of middle stage of anagen was observed and it were grown down to subcutaneous tissue of skin in all the normal mice on 15th day. But in control group, most of hair follicles of telogen phase was observed in skin. The treatment of extract of Arisaematis Rhizoma increased expression of IGF(145%) and placenta lactogen(108%) in the skin of normal C57BL/6N mice on the 11th day compared to control group(100%). But expression of TGF-${\beta}$(90%) and prolactin(91%) decreased in the skin of normal C57B/6N mice on the 11th day compared to control group(100%). After application of fractions(chloroform, ethyl acetate and water fractions) of Arisaematis Rhizoma extract for 9th day, hair growth effect was observed in whole skin area in 50% of normal mice. But in control group, hair growth effect was not observed in whole skin area of normal mice. Immunoreactive density of VEGF, c-kit, PKC-${\alpha$ and FGF in skin of fractions of Arisaematis Rhizoma extracts was strongly stained in epidermis, bulge, secondary hair germ cells, cutaneous trunci m., subcutaneous tissue, root sheath compare to control group on the 9th day. In spontaneous alopecia areata model, The hair growth activity of Arisaematis Rhizoma extrat treated group(75%) was observed to be strong compared to control group(O%) on 7th day. These experiments suggest that fractions and extracts of Arisaematis Rhizoma may stimulate the topical hair growth activity. Thus it can be useful for treatment of alopecia areata.

• 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.

• Molecules and Cells
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• 제42권6호
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• pp.470-479
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• 2019

Interstitial cells of Cajal (ICCs) are pacemaker cells that exhibit periodic spontaneous depolarization in the gastrointestinal (GI) tract and generate pacemaker potentials. In this study, we investigated the effects of ghrelin and motilin on the pacemaker potentials of ICCs isolated from the mouse small intestine. Using the whole-cell patch-clamp configuration, we demonstrated that ghrelin depolarized pacemaker potentials of cultured ICCs in a dose-dependent manner. The ghrelin receptor antagonist [D-Lys] GHRP-6 completely inhibited this ghrelin-induced depolarization. Intracellular guanosine 5'-diphosphate-${\beta}$-S and pre-treatment with $Ca^{2+}$-free solution or thapsigargin also blocked the ghrelin-induced depolarization. To investigate the involvement of inositol triphosphate ($IP_3$), Rho kinase, and protein kinase C (PKC) in ghrelin-mediated pacemaker potential depolarization of ICCs, we used the $IP_3$ receptor inhibitors 2-aminoethoxydiphenyl borate and xestospongin C, the Rho kinase inhibitor Y-27632, and the PKC inhibitors staurosporine, Go6976, and rottlerin. All inhibitors except rottlerin blocked the ghrelin-induced pacemaker potential depolarization of ICCs. In addition, motilin depolarized the pacemaker potentials of ICCs in a similar dose-dependent manner as ghrelin, and this was also completely inhibited by [D-Lys] GHRP-6. These results suggest that ghrelin induced the pacemaker potential depolarization through the ghrelin receptor in a G protein-, $IP_3$-, Rho kinase-, and PKC-dependent manner via intracellular and extracellular $Ca^{2+}$ regulation. In addition, motilin was able to depolarize the pacemaker potentials of ICCs through the ghrelin receptor. Therefore, ghrelin and its receptor may modulate GI motility by acting on ICCs in the murine small intestine.

• 대한한방부인과학회지
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• 제22권3호
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• pp.66-82
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• 2009

Purpose: This study was performed to elucidate the inhibitory effect of Yukmijihwangtang-gagambang (YMG) on melanin synthesis in B16F10 mouse melanoma cell. Methods: To demonstrate the inhibitory effects of YMG on melanin synthesis, we measured the amount of released and produced melanin in B16F10 melanoma cell. Also, we evaluated tyrosinase-activity in vitro as well as in B16F10 melanoma cell. And to investigate the action mechanism we assessed the gene expressions of tyrosinase, TRP-1, TRP-2, MMP-2, PKA, PKC${\beta}$, ERK-1 ERK-2, AKT-1 and MITF in B16F10 melanoma cells. Results: 1. YMG decreased the release and production of melanin in B16F10 melanoma cells. 2. YMG decreased tyrosinase activity in vitro and in B16F10 melanoma cells. 3. YMG decreased the expression of tyrosinase, TRP-1, TRP-2, PKA, PKC${\beta}$ and MMP-2 in B16F10 melanoma cells. 4. YMG increased the expression of ERK-1, ERK-2, and AKT-1 in B16F10 melanoma cells. 5. YMG decreased the expression of MITF in B16F10 melanoma cells. Conclusion: From these results, we suggest that YMG inhibit melanin synthesis via tyrosinase inhibition and regulation of the gene expression in B16F10 melanoma cells.

• BMB Reports
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• 제47권10호
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• pp.552-557
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• 2014

The main purpose of this study was to investigate whether type 3 muscarinic acetylcholine receptor (M3R) dysfunction induced vascular hyperpermeability. Transwell system analysis showed that M3R inhibition by selective antagonist 4-diphenylacetoxy-N-methylpiperidine methiodide (4-DAMP) and small interfering RNA both increased endothelial permeability. Using coimmunoprecipitation and Western blot assay, we found that M3R inhibition increased VE-cadherin and ${\beta}$-catenin tyrosine phosphorylation without affecting their expression. Using PTP1B siRNA, we found that PTP1B was required for maintaining VE-cadherin and ${\beta}$-catenin protein dephosphorylation. In addition, 4-DAMP suppressed PTP1B activity by reducing cyclic adenosine monophosphate (cAMP), but not protein kinase $C{\alpha}$ ($PKC{\alpha}$). These data indicate that M3R preserves the endothelial barrier function through a mechanism potentially maintaining PTP1B activity, keeping the adherens junction proteins (AJPs) dephosphorylation.

• The Korean Journal of Physiology and Pharmacology
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• 제7권6호
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• pp.349-355
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• 2003

We previously shown that LES contraction depends on $M_3$ receptors linked to PTX insensitive $G_q$ protein and activation of PLC. This results in production of $IP_3$, which mediates calcium release, and contraction through a CaM dependent pathway. In the esophagus ACh activates $M_2$ receptors linked to PTX sensitive $G_{i3}$ protein, resulting in activation of PLD, presumably, production of DAG. We investigated the role of PLC isozymes which can be activated by $G_q$ or $G{\beta}$ protein on ACh-induced contraction in LES and esophagus. Immunoblot analysis showed the presence of 3 types of PLC isozymes, $PLC-{\beta}1$, $PLC-{\beta}3$, and $PLC-{\gamma}1$, but not $PLC-{\beta}2$, $PLC-{\beta}4$, $PLC-{\gamma}2$, $PLC-{\delta}1$, and $PLC-{\delta}2$ from both LES and esophageal muscle. ACh produced contraction in a dose dependent manner in LES and esophageal muscle cells obtained by enzymatic digestion with collagenase. $PLC-{\beta}1$ or $PLC-{\beta}3$ antibody incubation reduced contraction in response to ACh in LES but not in esophageal permeabilized cells, but $PLC-{\gamma}1$ antibody incubation did not have an inhibitory effect. The inhibition by $PLC-{\beta}1$ or $PLC-{\beta}3$ antibody on Ach-induced contraction was antibody concentration dependent. The combination with $PLC-{\beta}_1$ and $PLC-{\beta}_3$ antibody completely abolished the contraction, suggesting that $PLC-{\beta}1$ and $PLC-{\beta}3$ have a synergism to inhibit the contraction in LES. $PLC-{\beta}1$, -${\beta}3$ or -${\gamma}1$ antibody did not reduce the contraction of LES cells in response to DAG ($10^{-6}$ M), suggesting that this isozyme of PLC may not activate PKC. When $G_{q/11}$ antibody was incubated, the inhibitory effect of the incubation of PLC ${\beta}3$, but not of PLC ${\beta}_1$ was additive (Fig. 6). In contrast, when $G_{\beta}$ antibody was incubated, the inhibitory effect of the incubation of PLC ${\beta}_1$, but not of PLC ${\beta}_3$ was additive. This data suggest that $G_{q/11}$/11 or $G{\beta}$ may activate cooperatively different PLC isozyme, $PLC{\beta}_1$ or $PLC{\beta}_3$ respectively.

• Molecules and Cells
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• 제38권7호
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• pp.616-623
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• 2015

P2 receptors are membrane-bound receptors for extracellular nucleotides such as ATP and UTP. P2 receptors have been classified as ligand-gated ion channels or P2X receptors and G protein-coupled P2Y receptors. Recently, purinergic signaling has begun to attract attention as a potential therapeutic target for a variety of diseases especially associated with gastroenterology. This study determined the ATP and UTP-induced receptor signaling mechanism in feline esophageal contraction. Contraction of dispersed feline esophageal smooth muscle cells was measured by scanning micrometry. Phosphorylation of $MLC_{20}$ was determined by western blot analysis. ATP and UTP elicited maximum esophageal contraction at 30 s and $10{\mu}M$ concentration. Contraction of dispersed cells treated with $10{\mu}M$ ATP was inhibited by nifedipine. However, contraction induced by $0.1{\mu}M$ ATP, $0.1{\mu}M$ UTP and $10{\mu}M$ UTP was decreased by U73122, chelerythrine, ML-9, PTX and $GDP{\beta}S$. Contraction induced by $0.1{\mu}M$ ATP and UTP was inhibited by $G{\alpha}i_3$ or $G{\alpha}q$ antibodies and by $PLC{\beta}_1$ or $PLC{\beta}_3$ antibodies. Phosphorylated $MLC_{20}$ was increased by ATP and UTP treatment. In conclusion, esophageal contraction induced by ATP and UTP was preferentially mediated by P2Y receptors coupled to $G{\alpha}i_3$ and $G{\alpha}q$ proteins, which activate $PLC{\beta}_1$ and $PLC{\beta}_3$. Subsequently, increased intracellular $Ca^{2+}$ and activated PKC triggered stimulation of MLC kinase and inhibition of MLC phosphatase. Finally, increased $pMLC_{20}$ generated esophageal contraction.

• 고려인삼학회:학술대회논문집
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• 고려인삼학회 2002년도 학술대회지
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• pp.66-83
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• 2002

Recently, we have provided evidence that ginsenosides, the active components of Panax ginseng, utilize pertussis toxin (PTX)-insensitive $G{\alpha}_{q/11}-phospholipase\;C-{\beta}3(PLC-{\beta}3)$ signal transduction pathway for the enhancement of $Ca^{2+}-activated\;Cl^{-}$ current in the Xenopus oocyte (British J. Pharmacol. 132, 641-647, 2001; JBC 276, 48797-48802, 2001). Other investigators have shown that stimulation of receptors linked to $G{\alpha}-PLC$ pathway inhibits the activity of G proteincoupled inwardly rectifying $K^+$ (GIRK) channel. In the present study, we sought to determine whether ginsenosides influenced the activity of GIRK 1 and GIRK 4 (GIRK 1/4) channels expressed in the Xenopus oocyte, and if so, the underlying signal transduction mechanism. In oocyte injected with GIRK 1/4 channel cRNAs, bath-applied ginsenosides inhibited high potassium (HK) solution-elicited GIRK current $(EC_{50}:4.9{\pm}4.3\;{\mu}g/ml).$ Pretreatment of the oocyte with PTX reduced the HK solution-elicited GIRK current by $49\%,$ but it did not alter the inhibitory ginsenoside effect on GIRK current. Prior intraoocyte injection of cRNA(s) coding $G{\alpha}_q,\;G{\alpha}_{11}\;or\;G{\alpha}_q/G{\alpha}_{11},\;but\;not\;G{\alpha}_{i2}\;or\;G{\alpha}_{oA}$ attenuated the inhibitory ginsenoside effect. Injection of cRNAs coding $G{\beta}_{1{\gamma}2}$ also attenuated the ginsenoside effect. Similarly, injection of the cRNAs coding regulators of G protein signaling 1, 2 and 4 (RGS1, RGS2 and RGS4), which interact with $G{\alpha}_i\;and/or\;G{\alpha}_{q/11}$ and stimulates the hydrolysis of GTP to GDP in active GTP-bound $G{\alpha}$ subunit, resulted in a significant reduction of ginsenoside effect on GIRK current. Preincubation of GIRK channel-expressing oocyte in PLC inhibitor (U73122) or protein kinase C (PKC) inhibitor (staurosporine or chelerythrine) blocked the inhibitory ginsenoside effect on GIRK current. On the other hand, intraoocyte injection of BAPTA, a free $Ca^{2+}$ chelator, had no significant effect on the ginsenoside action. Taken together, these results suggest that ginsenosides inhibit the activity of GIRK 1/4 channel expressed in the Xenopus oocyte through a PTX-insensitive and $G{\alpha}_{q/11}$-,PLC-and PKC-mediated signal transduction pathway.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제32권3호
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• pp.218-228
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• 2010

발암물질로 알려진 Hydroquinone (HQ)은 치과용 합성수지를 구성하는 중요한 성분으로서 지금까지 치과용 재료영역에서 널리 사용되고 있으며 구강 내에서 HQ의 유출이 일어나는 것으로 확인 되었다. 따라서 구강암의 기원이 되는 인체상피세포의 발암화에 HQ가 미치는 영향을 평가하였다. HQ에 의한 인체세포 독성을 평가하기위해 LDH assay를 실시하고 세포 독성이 높지 않은 용량을 실험 용량으로 설정하였다. 인체 세포의 발암화를 평가하기 위해 세포 발암화 지표로서 cell saturation density, soft-agar colony formation 및 cell aggregation의 분석을 사용한 결과 고용량인 50 ${\mu}M$을 제외한 모든 용량에서 발암화 지표의 변화를 나타내지 않아 HQ의 발암력은 매우 낮은 것으로 추정된다. 그러나 발암촉진제인 TPA와 함께 투여 시 발암력의 증가를 보여 주변 환경의 여건에 따라 발암력이 증가할 수 있음을 입증하였다. HQ를 노출 후 세포사멸화를 측정하기 위해 DNA fragmentation변화를 분석한 결과 10 ${\mu}M$부터 50 ${\mu}M$까지 노출 시간 의존형의 증가를 나타내었으며 50 ${\mu}M$과 같은 고용량 농도에서는 노출시간 의존적 세포사멸 효과를 보였다. 따라서 세포 발암화를 일으킨 용량에서 세포사멸도 함께 일어나 HQ에 의한 발암화에 세포사멸이 관여함을 보였다. HQ는 ROS를 생성하였으며 Trolox, NAC와 같은 항산화물에 의한 ROS의 차단 효과와 BSO와 같은 GSH 고갈 유발 물질에 따른 ROS의 급격한 증가는 HQ가 인체세포에서 ROS를 효율적으로 생성함을 입증하는 결과이다. 세포간의 신호전달기작 조절에 중요한 역할을 하는 효소인 protein kinase C (PKC)를 immunoblot으로 분석한 결과 PKC-${\alpha}$의 활성이 증가 된 반면 PKC-${\beta}II$의 영향은 나타나지 않았다. 따라서 특정 이성질체에 대한 특이적인 효소반응이 발암화에 관여할 것으로 추정된다. 본 연구결과 치과용 합성수지 구성성분인 HQ 유출에 따른 인체상피세포의 발암성은 매우 낮은 것으로 추정되나 발암촉진제 등과의 상호작용에 의한 발암성 증가는 HQ의 구강암 발생 평가에 고려되어야 할 사항이다. 따라서 본 연구는 구강암의 예방을 위한 과학적인 접근 방법 및 기반 자료를 제시하였고 치과용 합성수지사용의 적정성에 대한 과학적인 판단을 할 수 있는 근거를 제공 하였다. 또한 본 연구 결과는 새로운 치과용 합성수지 개발의 필요성 및 개선방향을 제시 할 수 있는 근거로 활용될 수 있을 것으로 사료된다.