• 한국독성학회:학술대회논문집
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• 한국독성학회 2001년도 International Symposium on Signal transduction in Toxicology
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• pp.168-168
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• 2001

The mycotoxin, ochratoxin A (OTA) has been known to induce microcephaly in animals and in vitro whole embryo. Cytotoxic effect and inhibition of cell differentiation were proposed as underlying mechanisms responsible for OTA-induced microcephaly.(omitted)

• 산업기술연구
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• 제40권1호
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• pp.1-6
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• 2020

In the process of protein transcription and translation, various protein complexes bind to DNA, and all processes are precisely controlled. Among the proteins constituting this complex, a peptide derived from eukaryotic initiation factor (eIF) 2 was synthesized. In addition, in order to increase the efficiency of transduction of this peptide into cells, peptides with polyarginine, one of the protein transduction domains (PTD), were synthesized. Cell growth inhibition was confirmed in HER2 positive breast cancer (SK-Br-3) and HER2 negative breast cancer (MDA-MB-231), and cardiomyocytes (H9c2). The peptide with polyarginine had high transduction efficiency in all cells, and had excellent cancer cell growth inhibitory effects. The peptide used in this study might be useful peptide therapeutics for the treatment of cancer through future research.

• Journal of Ginseng Research
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• 제39권1호
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• pp.1-6
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• 2015

Abnormal changes in skin color induce significant cosmetic problems and affect quality of life. There are two groups of abnormal change in skin color; hyperpigmentation and hypopigmentation. Hyperpigmentation, darkening skin color by excessive pigmentation, is a major concern for Asian people with yellowe-brown skin. A variety of hypopigmenting agents have been used, but treating the hyperpigmented condition is still challenging and the results are often discouraging. Panax ginseng has been used traditionally in eastern Asia to treat various diseases, due to its immunomodulatory, neuroprotective, antioxidative, and antitumor activities. Recently, several reports have shown that extract, powder, or some constituents of ginseng could inhibit melanogenesis in vivo or in vitro. The underlying mechanisms of antimelanogenic properties in ginseng or its components include the direct inhibition of key enzymes of melanogenesis, inhibition of transcription factors or signaling pathways involved in melanogenesis, decreasing production of inducers of melanogenesis, and enhancing production of antimelanogenic factor. Although there still remain some controversial issues surrounding the antimelanogenic activity of ginseng, especially in its effect on production of proinflammatory cytokines and nitric oxide, these recent findings suggest that ginseng and its constituents might be potential candidates for novel skin whitening agents.

• Biomolecules & Therapeutics
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• 제14권1호
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• pp.11-18
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• 2006

Certain flavonoids possess anti-inflammatory activity. Besides their antioxidative property, the cellular action mechanisms of flavonoids include an inhibition of arachidonate metabolizing enzymes such as cyclooxygenases and lipoxygenases, and a down-regulation of proinflammatory gene expression such as cyclooxygenase-2, inducible nitric oxide synthase and tumor necrosis factor-$\alpha$. In this review, the recent findings of anti-inflammatory flavonoid research since 2004 were summarized. And the cellular mechanisms on signal transduction pathways were also discussed.

• 생약학회지
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• 제44권2호
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• pp.104-109
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• 2013

Hesperidin (HES), a flavonone glycoside isolated from the citrus fruits such as lemons and oranges, has been reported to have many biological properties including antiinflammatory, antioxidant, and antiallergy activities. In this study, we focused on the action of HES modulating Th2-associated cytokines such as IL-4 and IL-13 expression in PMA/ionomycin (PI)-stimulated rat basophilic leukemia (RBL-2H3) cells. The production of IL-4 and IL-13 was quantified by ELISA and the mRNA expression was detected by using RT-PCR assay. In addition, western blot analysis was performed to determine the transcription factors involved in the cytokine expression. We found that HES significantly decreased PI-induced IL-4 and IL-13 productions and also decreased the level of mRNA in a dose-dependent manner. Furthermore, western blot analysis of the transcription factors implied that HES down-regulated the protein level of c-Jun and c-Fos, which are the activating protein 1 (AP-1) family and nuclear factor-kappaB (NF-${\kappa}B$) characterized as a transcription factors related to the Th2-associated cytokine expression. Taken together, our data showed that the action of HES responsible for antiallergy activities is based on suppression of Th2-associated cytokines through inhibition of AP-1 and NF-${\kappa}B$ transcription factors.

• Asian-Australasian Journal of Animal Sciences
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• 제29권10호
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• pp.1383-1391
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• 2016

Bovine embryonic stem cells have potential for use in research, such as transgenic cattle generation and the study of developmental gene regulation. The Nanog may play a critical role in maintenance of the undifferentiated state of embryonic stem cells in the bovine, as in murine and human. Nevertheless, efforts to study the bovine Nanog for pluripotency-maintaining factors have been insufficient. In this study, in order to understand the mechanisms of transcriptional regulation of the bovine Nanog, the 5'-flanking region of the Nanog was isolated from ear cells of Hanwoo. Results of transient transfection using a luciferase reporter gene under the control of serially deleted 5'-flanking sequences revealed that the -134 to -19 region contained the positive regulatory sequences for the transcription of the bovine Nanog. Results from mutagenesis studies demonstrated that the Sp1-binding site that is located in the proximal promoter region plays an important role in transcriptional activity of the bovine Nanog promoter. The electrophoretic mobility shift assay with the Sp1 specific antibody confirmed the specific binding of Sp1 transcription factor to this site. In addition, significant inhibition of Nanog promoter activity by the Sp1 mutant was observed in murine embryonic stem cells. Furthermore, chromatin-immunoprecipitation assay with the Sp1 specific antibody confirmed the specific binding of Sp1 transcription factor to this site. These results suggest that Sp1 is an essential regulatory factor for bovine Nanog transcriptional activity.

• Biomolecules & Therapeutics
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• 제20권6호
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• pp.499-505
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• 2012

Chemoprevention represents a strategy designed to protect cells or tissues against various carcinogens and carcinogenic metabolites derived from exogenous or endogenous sources. Recent studies indicate that plant-derived triterpenoids, like oleanolic acid, may exert cytoprotective functions via regulation of the activity of different transcription factors. The chemopreventive effects may be mediated through induction of the nuclear factor erythroid 2-related factor 2 (Nrf2) transcription factor. Activation of Nrf2 by triterpenoids induces the expression of phase 2 detoxifying and antioxidant enzymes such as NAD(P)H quinone oxidoreductase 1 (NQO1) and heme oxygenase-1 (HO-1) - proteins which can protect cells or tissues against various toxic metabolites. On the other hand, inhibition of other transcription factors, like NF-${\kappa}B$ leads to the decrease in the pro-inflammatory gene expression. Moreover, the modulation of microRNAs activity may constitute a new mechanism responsible for valuable effects of triterpenoids. Recently, based on the structure of naturally occurring triterpenoids and with involvement of bioinformatics and computational chemistry, many synthetic analogs with improved biological properties have been obtained. Data from in vitro and in vivo experiments strongly suggest synthetic derivatives as promising candidates in the chemopreventive and chemotherapeutic strategies.

• 대한화장품학회지
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• 제35권2호
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• pp.117-123
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• 2009

후박추출물은 중국 원산인 당후박에서 제조되며, 항산화 및 항염증 효과로 알려져 있다. 후박의 성분으로는 폴레페놀인 honokiol 및 magnolol 등이 알려져 있다. 이 연구에서, 우리는 후박추출물이 triglyceride (TG)의 축척을 감소시킴으로써 지방세포 분화를 억제한다는 표면적인 결과를 얻었다. 또한, 후박 추출물이 hormone sensitive lipase (HSL) 단백질 수준을 증가시키고 adipocyte에 specific한 transcription factors로 peroxisome proliferator activated receptor (PPAR)-${\gamma}$의 단백질과 mRNA 수준을 억제하였다. 결과적으로, 후박추출물이 항비만제로서 adipogenic transcription factor와 그들의 특이적인 유전자의 발현을 억제함으로써 지방세포 분화를 억제한다고 사료된다.

• 생명과학회지
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• 제23권11호
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• pp.1336-1341
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• 2013

아시아에서 한방약초로 널리 알려진 당귀 추출물의 미백활성을 알아보기 위하여 tyrosinase 저해활성을 측정한 결과 1,000 ${\mu}g/ml$의 농도에서 70% 이상의 활성을 나타내었다. 또한 당귀 추출물에 대한 멜라노마 세포(B16F10)의 세포생존율을 확인한 결과 500 ${\mu}g/ml$의 농도에서 99% 이상의 세포생존율을 확인할 수 있었다. 미백 관련 인자인 MITF, TRP-1, TRP-2 및 tyrosinase의 mRNA 발현량을 측정한 결과 50 ${\mu}g/ml$의 농도에서 각각 85.7%, 123.9%, 68.8%, 208%로 당귀 추출물을 처리하지 않은 군보다 감소하였음을 확인할 수 있었다. 이러한 연구 결과에 따라 당귀 추출물이 melanin 합성과 관련이 있는 유전자 발현의 억제효과가 있음을 확인할 수 있었으며, 미백 화장품 소재로서의 가능성을 확인하였다.

• The Korean Journal of Physiology and Pharmacology
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• 제26권5호
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• pp.347-355
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• 2022

Abdominal aortic aneurysm (AAA) is a life-threatening disorder worldwide. Fibroblast growth factor 21 (FGF21) was shown to display a high level in the plasma of patients with AAA; however, its detailed functions underlying AAA pathogenesis are unclear. An in vitro AAA model was established in human aortic vascular smooth muscle cells (HASMCs) by angiotensin II (Ang-II) stimulation. Cell counting kit-8, wound healing, and Transwell assays were utilized for measuring cell proliferation and migration. RT-qPCR was used for detecting mRNA expression of FGF21 and activating transcription factor 4 (ATF4). Western blotting was utilized for assessing protein levels of FGF21, ATF4, and markers for the contractile phenotype of HASMCs. ChIP and luciferase reporter assays were implemented for identifying the binding relation between AFT4 and FGF21 promoters. FGF21 and ATF4 were both upregulated in Ang-II-treated HASMCs. Knocking down FGF21 attenuated Ang-II-induced proliferation, migration, and phenotype switch of HASMCs. ATF4 activated FGF21 transcription by binding to its promoter. FGF21 overexpression reversed AFT4 silencing-mediated inhibition of cell proliferation, migration, and phenotype switch. ATF4 transcriptionally upregulates FGF21 to promote the proliferation, migration, and phenotype switch of Ang-II-treated HASMCs.