• Journal of Ginseng Research
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• 제40권4호
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• pp.325-333
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• 2016

Background: Ginseng extracts are known to have angiogenic effects. However, to date, only limited information is available on the molecular mechanism underlying the angiogenic effects and the main components of ginseng that exert these effects. Human umbilical-vein endothelial cells (HUVECs) are used as an in vitro model for screening therapeutic agents that promote angiogenesis and wound healing. We recently isolated gintonin, a novel ginseng-derived lysophosphatidic acid (LPA) receptor ligand, from ginseng. LPA plays a key role in angiogenesis and wound healing. Methods: In the present study, we investigated the in vitro effects of gintonin on proliferation, migration, and tube formation of HUVECs, which express endogenous LPA1/3 receptors. Results: Gintonin stimulated proliferation and migration of HUVECs. The LPA1/3 receptor antagonist, Ki16425, short interfering RNA against LPA1 or LPA3 receptor, and the Rho kinase inhibitor, Y-27632, significantly decreased the gintonin-induced proliferation, migration, and tube formation of HUVECs, which indicates the involvement of LPA receptors and Rho kinase activation. Further, gintonin increased the release of vascular endothelial growth factors from HUVECs. The cyclooxygenase-2 inhibitor NS-398, nuclear factor kappa B inhibitor BAY11-7085, and c-Jun N-terminal kinase inhibitor SP600125 blocked the gintonin-induced migration, which shows the involvement of cyclooxygenase-2, nuclear factor kappa B, and c-Jun N-terminal kinase signaling. Conclusion: The gintonin-mediated proliferation, migration, and vascular-endothelial-growth-factor release in HUVECs via LPA-receptor activation may be one of in vitro mechanisms underlying ginsenginduced angiogenic and wound-healing effects.

• 한국동물학회지
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• 제32권2호
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• pp.153-162
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• 1989

난자성숙 재개와 1-세포기 배아의 세포주기에서, cAMP-의존성 protein kinase A와 diacylglycerol-의존성 protein kinase C가 핵막붕괴에 미치는 영향을 조사하였다. 난자성숙 재기는 dbcAMP, IBMX, TPA, 또는 diacyllycerol에 의해 억제되었다. 또한 protein kinase A와 protein kinase C 활성제를 같이 처리하면 난자성숙이 더욱 억제되었다. 그러나 1-세포기 배아의 전핵막붕괴에는 아무런 영향도 미치지 못하였으며, 단지 protein kinase C 활성제만이 세포질 분열을 억제하였다. 이상의 결과로부터, protein kinase A와 protein kinase C에 의한 단백질 인산화 양상이 GV난자의 핵막붕괴와 1-세포기 배아의 전핵막붕괴에 미치는 세포내 작용기작은 상이함을 알 수 있었으며, 전기영동 결과, 81 KD 단백질이 난자성숙 재개에 중요한 역할을 하리라 사료되었다.

• 한국미생물·생명공학회지
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• 제32권1호
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• pp.72-77
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• 2004

본 연구진은 토양미생물의 배양액으로부터 cyclin-dependent kinase 저해활성의 Toyocamycin을 분리하였으며 〔16〕, 화학적 전합성을 통하여 활성이 개선된 유도체인 신물질 MCS-5A를 합성하였다〔3〕. 이 MCS-5A를 이용한 항암 기전규명을 위한 연구를 통하여 , human promyelocytic leukemia cell(HL-60)에서 MCS-5A에 의해 cyclin-dependent kinase inhibitor p16$^{INK4A}$ 단백질의 발현증가가 암세포의 세포주기 억제와 동시에 HL-60 cell희 세포사멸을 유도하는 것을 확인하였다(data not shown). 그러나 HL-60 cell의 경우와는 달리 non small cell lung cancer cell(NSCLC)인 A549 cell(p16$^{INK4A}$ 결핍 세포주)에 MCS-5A를 처리할 경우에는 전혀 세포사멸이 유도되지 않았다. 따라서 MCS-5A에 의한 HL-60 cell에서의 세포사멸 유도는 발암억제 유전자인 P16$^{INK4A}$의 세포 내 발현 및 존재 여부에 의해 좌우되는 것으로 판단되었다. 이러한 배경에서 본 연구는 p16$^{INK4A}$.의 기존에 알려진 세포주기 억제를 유발하는 cyclin-dependent kinase inhibitor(CKI)로서의 역할 뿐 아니라, p16$^{INK4A}$ 유전자가 세포사멸을 유도할 수 있다는 새로운 기능을 규명하기 위하여 다음의 연구를 시도하였다. 즉 $p^{INK4A}$ 결핍 세포주인 A549(-p16/+p53)와 H1299(-pl6/-p53) 그리고 p16$^{INK4A}$ 함유 세포주인 HeLa(+p16/+p53)세포에 외부로부터 p16$^{INK4A}$ 유전자를 도입시켜, 각 세포주에서의 세포사멸 유도 여부를 비교하고자 하였다. 우선 wild-type p16$^{INK4A}$ 유전자를 가진 HeLa cell에서 총 RNA를 추출하여, 역전사 반응으로 cDNA를 만들고, PCR을 통해 p16$^{INK4A}$ 유전자를 증폭하였다. pcDNA3.1/His is A vector에 p16$^{INK4A}$ 유전자를 끼워 넣고 competent cell (XL1-Blue)에 형질 전환하여 cloning한 후, p16$^{INK4A}$ clone을 다량으로 추출하였다. 위에 언급한 각각의 cell line에 p16$^{INK4A}$유전자를 농도(0, 1, 5, 10$\mu\textrm{g}$)별로 transfection 시킨 후, p16 단백질을 일정 시간 동안(12시간) 발현시킨 뒤, TUNEL등의 분석을 통해 세포사멸이 유도되는지를 확인하였으며, 또한 Western blot 분석을 통하여 p16단백질과 세포사멸 유도 인자인 caspase 3의 발+현 양상을 확인하였다. 연구 결과, Western blot을 통해 transfection시킨 p16/INK4A/유전자의 농도에 따라 각각의 cell line에서 Pro-caspase 3의 감소함을 관찰할 수 있었고, TUNEL분석을 통해 A549및 HeLa cell에서 세포사멸이 유도됨을 확인할 수 있었다 특히 A549(-p16/+p53)와 HeLa cell(+p16/+p53)에서는 TUNEL 분석 및 Western blot을 통한 pro-caspase 3의 caspase 3로의 전환 등을 통해 세포사멸이 발생하였음을 확연하게 확인할 수 있었으나, 반면 H1299(-pl6/-p53) cell에서는 단지 Western blot을 통한 pro-caspase 3의 활성화만을 통해 간접적으로 세포사멸을 확인 할 수 있었다. 또한 p53이 결핍된 H1299(-pl6/-p53)세포주에서의 $^{INK4A}$ 에 의한 세포사멸 유도는 p53 비의존적으로 작용한다는 사실을 확인할 수 있었다. 결론적으로 발암억제 유전자인 $^{INK4A}$ 는 CKI로서의 기능뿐 아니라, 세포사별 유도와도 밀접하게 관련되어 있으며, 이 기능은 발암 억제 유전자인 p53과는 독립적으로 작용한다는 사실을 확인하였다. 세포사멸 유도 기전연구에서 $p16^{INK4A}$ 가 세포사멸을 유도하는 기전에 대해서는 아직 명확하게 밝혀진 바는 없으며, 현재 본 연구실에서 다양한 실험을 통해 연구가 진행 중이다.

• 통합자연과학논문집
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• 제9권2호
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• pp.113-120
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• 2016

Monopolar spindle 1 (Mps1) is an attractive cancer target due to its high expression levels in a wide range of cancer cells. Mps1 is a dual specificity kinase. It plays an essential role in mitosis. The high expression od Mps1 was observed in various grades of breast cancers. In the current study, we have developed a CoMFA model of pyridazine derivatives as Mps1 kinase inhibitors. The developed CoMFA model ($q^2=0.797$; ONC=6; $r^2=0.992$) exhibited a good predictive ability. The model was then validated by Leave out five, progressive sampling and bootstrapping and found to be robust. The analysis of the CoMFA contour maps depicted favorable and unfavorable regions to enhance the activity. Bulky positive substitution at $R^3$ position and Negative substitution in $R^1$ position is favored could increase the activity. In contrast, bulky substitution in $R^1$ position is not favored. Our results can be used in designing a potent Mps1 (TTK) inhibitor.

• Natural Product Sciences
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• 제15권1호
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• pp.32-36
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• 2009

Glutamate causes neurotoxicity through formation of reactive oxygen species and activation of mitogen-activated protein kinase (MAPK) pathways. MAPK phosphatase-1 (MKP-1) is one of the phosphatases responsible for dephosphorylation/deactivation of three MAPK families: the extracellular signal-regulated kinase-1/2 (ERK-1/2), the c-Jun N-terminal kinase-1/2 (JNK-1/2), and the p38 MAPK. In this report, the potential involvement of MKP-1 in neuroprotective effects of curcumin, the active ingredient of turmeric (Curcuma longa), was examined using HT22 cells. Glutamate caused cell death and activation of ERK-1/2 but not p38 MAPK or JNK-1/2. Blockage of ERK-1/2 by its inhibitor protected HT22 cells against glutamate-induced toxicity. Curcumin attenuated glutamate-induced cell death and ERK-1/2 activation. Interestingly, curcumin induced MKP-1 activation. In HT22 cells transiently transfected with small interfering RNA against MKP-1, curcumin failed to inhibit glutamate-induced ERK-1/2 activation and to protect HT22 cells from glutamate-induced toxicity. These results suggest that curcumin can attenuate glutamate-induced neurotoxicity by activating MKP-1 which acts as the negative regulator of ERK-1/2. This novel pathway may contribute to and explain at least one of the neuroprotective actions of curcumin.

• 대한한방부인과학회지
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• 제15권4호
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• pp.1-16
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• 2002

This work examines the effect of treatment with Gyukhachukeotang on the growth of uterine myomal cells. Comparisons of cell growth, MAP kinase activity and expression of bcl-2 (apoptosis-related gene) were made between the control and experimental samples. The results as fallows; 1. Any concentration of Gyukhachukeotang above 0.01% yielded growth inhibition. Concentrations of 5% and 10% stopped all cell growth, demonstrating the effectiveness of Gyukhachukeotang as a growth inhibitor on uterine myomal cells. 2. The MAP kinase activity in uterine myomal cells treated with Gyukhachukeotang was decreased to a high degree at the concentration of 10%, and some inhibition of activity was detected at a concentration of 5%. 3. The expression of bcl-2, a Cell Apoptosis-related gene, in uterine myoma cells treated with Gyukhachukeotang was gradually increased with increasing concentration of Gyukhachukeotang. These results indicate the ability of Gyukhachukeotang to control uterine myomal cell growth, with concurrent reduction of MAP kinase activity. Treatment with Gyukhachukeotang appears to trigger a normal apoptosis response, as indicated by increased bcl-2 expression. This observed increase in apoptosis indicates that Gyukhachukeotang is an appropriate prescription to treat uterine myomal cells.

• Molecules and Cells
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• 제26권1호
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• pp.48-52
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• 2008

We here demonstrate an anti-inflammatory action of raloxifene, a selective estrogen receptor modulator, in lipopolysaccharide (LPS)-induced murine macrophage RAW264.7 cells. Treatment with raloxifene at micromolar concentrations suppressed the production of nitric oxide (NO) by down-regulating expression of the inducible nitric oxide synthase (iNOS) gene in LPS-activated cells. The decreased expression of iNOS and subsequent reduction of NO were due to inhibition of nuclear translocation of transcription factor NF-${\kappa}B$. These effects were significantly inhibited by exposure to the phosphatidylinositol 3-kinase (PI 3-kinase) inhibitor, LY294002, or by expression of a dominant negative mutant of PI 3-kinase. In addition, pretreatment with raloxifene reduced LPS-induced Akt phosphorylation as well as NF-${\kappa}B$ DNA binding activity and NF-${\kappa}B$-dependent reporter gene activity. Thus our findings indicate that raloxifene exerts its anti-inflammatory action in LPS-stimulated macrophages by blocking the PI 3-kinase-Akt-NF-${\kappa}B$ signaling cascade, and eventually reduces expression of pro-inflammatory genes such as iNOS.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2001년도 International Symposium on Signal transduction in Toxicology
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• pp.9-13
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• 2001

Genistein, a natural isoflavonoid phytoestrogen, is a strong inhibitor of protein tyrosine kinase and DNA topoisomerase II activities. Genistein has been shown to have anticancer proliferation, differentiation and chemopreventive effects. In the present study, we have addressed the mechanism of action by which genistein suppressed the proliferation of p53-null human prostate carcinoma cells.(omitted)

• Bulletin of the Korean Chemical Society
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• 제32권3호
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• pp.1077-1079
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• 2011

• Asian-Australasian Journal of Animal Sciences
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• 제16권8호
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• pp.1199-1204
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• 2003

The aim of this study was to investigate the role of phosphatidylinositol 3-kinase (PI3 kinase) and the mitogenactivating protein (MAP) kinase pathway on the differentiation of ovine preadipocytes. In order to investigate this issue, we monitored glycerol 3-phosphate dehydrogenase (GPDH) activity during differentiation with specific inhibitors of PI3 kinase and MAP kinase-Erk kinase, LY294002 and PD098059, respectively. The preadipocytes, which were obtained from ovine subcutaneous adipose tissues, were proliferated to confluence and then differentiated to adipocytes in differentiation medium with each inhibitor for 10 days. The confluent preadipocytes and differentiated adipocytes at days 3, 7 and 10 were harvested for assay of GPDH activity. LY294002 inhibited the differentiation program in dose- and day-dependent manners during 10 days of differentiation. PD098059 did not affect GPDH activity during differentiation. Furthermore, the expression of peroxisome proliferator-activated receptor ${\gamma}2$ (PPAR-${\gamma}2$), the representative early gene of differentiation, was markedly reduced by LY294002 treatment, although PD098059 did not change it. Our results demonstrated that the activation of PI3 kinase contributes to the differentiation process of ovine preadipocytes.