• 대한의생명과학회지
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• 제11권2호
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• pp.175-183
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• 2005

The two major isoflavones in soy, genistein and daidzein, are well known to prevent hormone-dependent cancers by their anti estrogenic activity. The exact molecular mechanisms for the protective action are, however, not provided yet. It has been reported that genistein and daidzein have a potential anticancer activity through their antiproliferative effect in many hormone-dependent cancer cell lines. Transforming growth $factor-\beta1(TGF-\beta1)$ has also been found to have cell growth inhibitory effect, especially in mammary epithelial cells. This knowledge led to a hypothetical mechanism that the soy isoflavones-induced growth inhibitory effect can be derived from the regulation of $TGF-\beta1$ and $TGF-\beta$ receptors. In order to test this hypothesis, the effects of the soy isoflavones at various concentrations and periods on the expression of $TGF-\beta1$and $TGF-\beta$ receptors were investigated by using Northern blot analysis in human breast carcinoma epithelial cell lines, an estrogen receptor positive cell line (MCF-7) and an estrogen receptor negative cell line (MDA-MB-231). As a result, only genistein has shown a profound dose-dependent effect on $TGF-\beta1$ expression in the $ER^+$ cell line within the range of doses tested, and the expression levels are correspondent to their inhibitory activities of cell growth. Moreover, daidzein showed down-regulated $TGF-\beta1$ expression at a low dose, the cell growth proliferation was promoted at the same condition. Therefore, antiproliferative activity of the soy isoflavones can be mediated by $TGF-\beta1$ expression, and the effects are mainly, if not all, occurred by ER dependent pathway. The expression of $TGF-\beta$ receptors was induced at a lower dose than the one for $TGF-{\beta}1$ induction regardless of the presence of ER, and the expression patterns are similar to those of the cell growth inhibition. These results indicated that the regulation of $TGF-\beta$ receptor expression as well, prior to $TGF-\beta1$ expression, may be involved in the antiproliferative activity of soy isoflavones. Little or no expression of $TGF-\beta$ receptors was found in the MCF-7 and MDA-MB-231 cells, suggesting refractory properties of the cells to growth inhibitory effect of the $TGF-\beta$. The soy isoflavones can seemingly restore the sensitivity of growth inhibitory responses to $TGF-\beta1$ by re-inducing $TGF-\beta$ receptors expression. In conclusions, our findings presented in this study show that the antitumorigenic activity of the soy isoflavones could be mediated by not only $TGF-\beta1$induction but $TGF-\beta$ receptor restoration. Thus, soy isoflavones could be good model molecules to develop new nonsteroidal antiestrogenic chemopreventive agents, associated with, regulation of $TGF-\beta$ and its receptors.

• 생명과학회지
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• 제29권2호
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• pp.256-264
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• 2019

Lymphotoxin ${\beta}$ receptor ($LT{\beta}R$)는 TNF 계열로 림프조직의 미세구조와 기관형성에 중요한 역할을 한다. MLCK와 ROCK는 세포의 stress fiber 형성조절에 관여하는 주요 신호전달자이다. Fibroblastic reticular cell (FRC)에서 $LT{\beta}R$ 자극을 통한 이런 신호전달자들의 관련성을 알아보기 위해 ML-7 (MLCK 저해제)이 사용되었다. ML7 처리된 FRC에서 SF가 완전히 파괴되었고 anti-$LT{\beta}R$ antibody 처리 세포와 유사하게 ML7 처리 FRC에서 응축된 세포형태를 관찰 할 수 있었다. Y27632로 ROCK를 저해 했을 때 FRC의 액틴 세포골격과 세포형태 변화가 유도 되었다. FRC에서 p-MLC가 액틴과 함께 SF 구성성분을 이루었다. FRC세포 추출물로 Rho-guanosine diphosphate (GDP)/guanosine triphosphate (GTP) 교환활성을 확인했다. Agonistic anti-$LT{\beta}R$ antibody로 $LT{\beta}R$을 자극 했을 때 Rho-GDP/GTP 교환활성이 크게 감소했다. MLCK 저해처럼 $LT{\beta}R$ 자극은 MLC의 인산화를 감소시켰다. Agonistic anti-$LT{\beta}R$ antibody-treated FRC에서 세포골격 구성요소인 세포막과 세포골격 링커 역할을 하는 p-ezrin의 인산화는 감소 되었고 b- actin, 그리고 tubulin 발현도 줄었다. 이런 결과는 FRC의 $LT{\beta}R$ 신호전달을 통한 SF 조절에는 MLCK와 ROCK가 관여하고 있다는 것을 알 수 있었다.

• International Journal of Oral Biology
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• 제37권1호
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• pp.1-7
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• 2012

Opioid receptors have been pharmacologically classified as ${\mu}$, ${\delta}$, ${\kappa}$ and ${\varepsilon}$. We have recently reported that the antinociceptive effect of morphine (a ${\mu}$-opioid receptor agonist), but not that of ${\beta}$-endorphin (a novel ${\mu}/{\varepsilon}$-opioid receptor agonist), is attenuated by whole body irradiation (WBI). It is unclear at present whether WBI has differential effects on the antinociceptive effects of ${\mu}-$, ${\delta}-$, ${\kappa}-$ and ${\varepsilon}$-opioid receptor agonists. In our current experiments, male ICR mice were exposed to WBI (5Gy) from a $^{60}Co$ gamma-source and the antinociceptive effects of opioid receptor agonists were assessed two hours later using the hot water ($52^{\circ}C$) tail-immersion test. Morphine and $D-Ala^2$, $N-Me-Phe^4$, Gly-olenkephalin (DAMGO), [$D-Pen^2-D-Pen^5$] enkephalin (DPDPE), trans-3,4-Dichloro-N-methyl-N-[2-(1-pyrrolidinyl)-cyclohexyl]-benzeneacetamide (U50,488H), and ${\beta}$-endorphin were tested as agonists for ${\mu}$, ${\delta}$, ${\kappa}$, and ${\varepsilon}$-opioid receptors, respectively. WBI significantly attenuated the antinociceptive effects of morphine and DAMGO, but increased those of ${\beta}$-endorphin. The antinociceptive effects of DPDPE and U50,488H were not affected by WBI. In addition, to more preciously understand the differential effects of WBI on ${\mu}-$ and ${\varepsilon}$-opioid receptor agonists, we assessed pretreatment effects of ${\beta}$-funaltrexamine (${\beta}$-FNA, a ${\mu}$-opioid receptor antagonist) or ${\beta}$-$endorphin_{1-27}$ (${\beta}$-$EP_{1-27}$, an ${\varepsilon}$-opioid receptor antagonist), and found that pretreatment with ${\beta}$-FNA significantly attenuated the antinociceptive effects of morphine and ${\beta}$-endorphin by WBI. ${\beta}$-$EP_{1-27}$ significantly reversed the attenuation of morphine by WBI and significantly attenuated the increased effects of ${\beta}$-endorphin by WBI. The results demonstrate differential sensitivities of opioid receptors to WBI, especially for ${\mu}-$ and ${\varepsilon}$-opioid receptors.

• Biomolecules & Therapeutics
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• 제25권1호
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• pp.44-56
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• 2017

Insulin resistance is characterized by the reduced ability of insulin to stimulate tissue uptake and disposal of glucose including cardiac muscle. These conditions accelerate the progression of heart failure and increase cardiovascular morbidity and mortality in patients with cardiovascular diseases. It is noteworthy that some conditions of insulin resistance are characterized by up-regulation of the sympathetic nervous system, resulting in enhanced stimulation of ${\beta}$-adrenergic receptor (${\beta}$AR). Overstimulation of ${\beta}$ARs leads to the development of heart failure and is associated with the pathogenesis of insulin resistance in the heart. However, pathological consequences of the cross-talk between the ${\beta}$AR and the insulin sensitivity and the mechanism by which ${\beta}$AR overstimulation promotes insulin resistance remain unclear. This review article examines the hypothesis that ${\beta}$ARs overstimulation leads to induction of insulin resistance in the heart.

• Biomolecules & Therapeutics
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• 제24권5호
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• pp.517-522
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• 2016

${\beta}$-Arrestins are one of the protein families that interact with G protein-coupled receptors (GPCRs). The roles of ${\beta}$-arrestins are multifaceted, as they mediate different processes including receptor desensitization, endocytosis, and G protein-independent signaling. Thus, determining the GPCR regions involved in the interactions with ${\beta}$-arrestins would be a preliminary step in understanding the molecular mechanisms involved in the selective direction of each function. In the current study, we determined the roles of the N-terminus, intracellular loops, and C-terminal tail of a representative GPCR in the interaction with ${\beta}$-arrestin2. For this, we employed dopamine $D_2$ and $D_3$ receptors ($D_2R$ and $D_3R$, respectively), since they display distinct agonist-induced interactions with ${\beta}$-arrestins. Our results showed that the second and third intracellular loops of $D_2R$ are involved in the agonist-induced translocation of ${\beta}$-arrestins toward plasma membranes. In contrast, the N- and C-termini of $D_2R$ exerted negative effects on the basal interaction with ${\beta}$-arrestins.

• Molecules and Cells
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• 제38권2호
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• pp.105-111
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• 2015

The beta2-adrenergic receptor (${\beta}2AR$) belongs to the G protein coupled receptor (GPCR) family, which is the largest family of cell surface receptors in humans. Extra attention has been focused on the human GPCRs because they have been studied as important protein targets for pharmaceutical drug development. In fact, approximately 40% of marketed drugs directly work on GPCRs. GPCRs respond to various extracellular stimuli, such as sensory signals, neurotransmitters, chemokines, and hormones, to induce structural changes at the cytoplasmic surface, activating downstream signaling pathways, primarily through interactions with heterotrimeric G proteins or through G-protein independent pathways, such as arrestin. Most GPCRs, except for rhodhopsin, which contains covalently linked 11 cis-retinal, bind to diffusible ligands, having various conformational states between inactive and active structures. The first human GPCR structure was determined using an inverse agonist bound ${\beta}2AR$ in 2007 and since then, more than 20 distinct GPCR structures have been solved. However, most GPCR structures were solved as inactive forms, and an agonist bound fully active structure is still hard to obtain. In a structural point of view, ${\beta}2AR$ is relatively well studied since its fully active structure as a complex with G protein as well as several inactive structures are available. The structural comparison of inactive and active states gives an important clue in understanding the activation mechanism of ${\beta}2AR$. In this review, structural features of inactive and active states of ${\beta}2AR$, the interaction of ${\beta}2AR$ with heterotrimeric G protein, and the comparison with ${\beta}1AR$ will be discussed.

• Journal of Yeungnam Medical Science
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• 제28권2호
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• pp.153-164
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• 2011

Background: It has been reported that estrogen receptor beta ($ER{\beta}$) mRNA expression was down-regulated during carcinogenesis and was inversely related to estrogen receptor alpha ($ER{\alpha}$) expression in breast cancer. The association of $ER{\beta}$ mRNA expression to tamoxifen resistance has also been reported. In this study, the expression of $ER{\alpha}$ and $ER{\beta}$ via immunohistochemistry (IHC) and reverse transcription-polymerase chain reaction (RT-PCR) was prompted, and an attempt was made to find out the relationship between $ER{\beta}$ expression and recurrence in the hormonal therapy group, and between $ER{\beta}$ expression and known prognostic factors. Methods: Tumor specimens were obtained at surgery from 67 female breast cancer patients during the period of September 1995 to December 2000. All the specimens were frozen in liquid nitrogen and kept at $-70^{\circ}C$ until they were used. The medical records were analyzed retrospectively. The expressions of ER were analyzed using IHC and RT-PCR methods. Results: The median follow-up was at 93.0 months (range: 14-157 months). The percentage of $ER{\alpha}+/ER{\beta}+$, $ER{\alpha}+/ER{\beta}-$, $ER{\alpha}-/ER{\beta}+$, and $ER{\alpha}-/ER{\beta}$ group were 35.9% 9.4%, 47.2%, and 7.5%, respectively, in 53 patients with hormonal therapy. $ER{\beta}$ was positive in 42 (82.3%) of 51 ER-positive patients. In the hormonal therapy group, the recurrence rates of each group was 15.8%, 0%, 40.0%, and 0%, respectively. In this group, the $ER{\beta}$ expression tended to recur, but there was no clinical significance (p=0.084). Conclusion: The $ER{\beta}$ expression may be a predictive marker of a poor response to endocrine therapy in breast cancer patients, although this needs to be confirmed in additional studies.

• Journal of Microbiology and Biotechnology
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• 제12권1호
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• pp.65-70
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• 2002

A TGF-${\beta}1$/GFP monomeric fusion protein was cloned from pPK9A and pGFP-Cl plasmid by PCR amplification. The fusion protein was expressed in a $Bac-To-Bac^{TM}$ baculovirus expression system. A 45 kDa fusion protein was purified using an Ni-NTA column with 300 mM imidazol from a cell lysate infected with recombinant viruses for 72 h post-infection. The fusion protein cross-reacted with the commercial $TGF-{\beta}1$ polyclonal Ab as well as Ab raised against a precursor, monomeric $TGF-{\beta}1$, and GFP. The binding activity of the fusion protein with a $TGF-{\beta}1$ receptor was examined. Fluorescence was observed in Mv1Lu cells, yet not in insect cells treated with the fusion protein. No fluorescence was detected in Mv1Lu cells incubated with the fusion protein treated with Ab prior to the binding reaction, or with GFP alone, thereby indicating that the binding of the fusion protein was specific to $TGF-{\beta}1$ with a receptor.

• 한국환경독성학회:학술대회논문집
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• 한국환경독성학회 2002년도 추계국제학술대회
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• pp.164-164
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• 2002

에스트로젠을 처리한 송사리의 간으로부터 choriogenin vitellogenin estrogen receptor의 발현량을 전사수준에서 Real-time을 사용하여 정량.비교하였다. 시험어종으로는 부화 후 5개월 이상된 성숙한 수컷 송사리(Oryzias latipes)를(체중 약 250mg/마리)를 사용하여 17$\beta$-estradiol(25ppt, 50ppt, 100ppt)에 24시간 노출시켰다. Fluorescence dye는 choriogenin vitellogenin estrogen receptor의 경우 FAM (6-carboxyfluorescein)을 사용하였으며, $\beta$-actin의 경우는 VIC를 사용하였다. 프로브에 사용하는 quencher dye는 TAMRA(6-carboxy-N',N',N',N'-tetramethyl rhodamine)을 사용하였다. Internal control로 사용된 $\beta$-actin은 17$\beta$-estradiol의 농도에 상관 없이 0~10pM 범위에서 일정하게 발현됨을 보여주었다. vitellogenin choriogenin L 및 choriogenin H는 17$\beta$-estradiol의 농도에 의존하여 발현이 증가되는 용량-반응양상(Dose-dependent)을 나타내었다. 반면, estrogen receptor는 모든 처리군에서 $10^{-2}$pM 정도로 발혐됨에 따라 본 시험농도의 17$\beta$-estradiol에 의해서는 거의 유도발현이 되지 않음을 보여주었다. choriogenin L, choriogenin H, vitellogenin I 및 estrogen receptor 발현감수성을 비교한 결과, 25ppt 및 50ppt의 17$\beta$-esoadiol 농도에서는 ChgL > ChgH > VTG I >ER의 순으로 감수성이 높았으며, 100ppt 노출에서는 ChgL > VTG I > Chg H > ER의 순으로 감수성이 높게 나타났다. 결론적으로 choriogenin이 에스트로젠물질에 의한 가장 민감한 생체지표임을 알 수 있었다.

• 생명과학회지
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• 제28권3호
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• pp.307-313
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• 2018

탈모증상은 겉으로 보이는 모습으로 인해 정신적인 스트레스로 작용한다. 그래서 탈모 방지관련 제품의 글로벌 시장 규모는 지속적으로 성장하고 있다. Timosaponin A III는 지모 추출물에서 발견되는 대표적인 saponin 계열의 생리 활성 효능 성분이다. 본 연구에서는 5-beta reductase 단백질 길항제(antagonist) finasteride, androgen receptor 단백질 길항제 minoxidil, 그리고 지모 추출물의 효능 성분 timosaponin A III의 각각의 타깃 단백질 활성 부위에 대한 친화도 분석 실험을 in silico 컴퓨터 분자결합 분석 방법을 통해 비교하였다. 5-beta reductase 및 androgen receptor 의 3차원 구조 정보는 PDB database (5-beta reductase PDB ID: 3G1R / androgen receptor PDB ID:4K7A)를 활용하였다. In silico 결합 분석을 수행하기 위해 PyRx, Autodock Vina, Discovery Studio Version 4.5, and NX-QuickPharm 프로그램을 각 분석 조건에 따라 활용하였다. 5-beta reductase 활성 부위에 대한 timosaponin A III의 최대 결합친화도는 -12.20 kcal/mol으로 나왔으며 이는 -11.70 kcal/mol으로 분석된 finasteride의 5-beta reductase 활성부위에 대한 결합 친화도 보다 훨씬 더 높고 효율적인 것으로 분석되었다. Androgen receptor 활성 부위에 대한 timosaponin A III의 최대결합친화도 또한 -9.00 kcal/mol으로 -7.40 kcal/mol의 minoxidil에 비하여 훨씬 우수한 결합친화도 값을 나타내었다. Finasteride와 timosaponin A III의 5-beta reductase 단백질 활성 부위에 대한 X,Y,Z Grid 값은 유사한 좌표로 분석되었으나 minoxidil과 timosaponin A III의 androgen receptor 활성 부위에 대한 X,Y,Z centroid grid 좌표는 상당한 거리를 두고 떨어져 있음이 확인 되었다. 즉, timosaponin A III는 minoxidil이 androgen receptor에 결합하는 부위와는 다른 부위에 결합하여 단백질 활성에 영향을 주는 것으로 사료되었다. 이상의 연구 결과들을 바탕으로 분석해 볼 때, 5-beta reductase 길항제 finasteride와 androgen receptor 길항제 minoxidil보다 지모 추출물 생리 활성 물질인 timosaponin A III가 보다 더 효율적인 길항제로 작용할 수 있음을 확인하였다. 결론적으로 지모 추출물 또는 timosaponin 계열이 함유된 효능 성분은 탈모 방지 효능 및 모발 건강 개선을 위한 의약품, 의약외품 및 신물질 연구 개발 분야에 효율적으로 활용할 수 있을 것으로 사료된다.