• 제목/요약/키워드: Transcription inhibition

검색결과 574건 처리시간 0.032초

Activating transcription factor-3 induction is involved in the anti-inflammatory action of berberine in RAW264.7 murine macrophages

  • Bae, Young-An;Cheon, Hyae Gyeong
    • The Korean Journal of Physiology and Pharmacology
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    • 제20권4호
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    • pp.415-424
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    • 2016
  • Berberine is an isoquinoline alkaloid found in Rhizoma coptidis, and elicits anti-inflammatory effects through diverse mechanisms. Based on previous reports that activating transcription factor-3 (ATF-3) acts as a negative regulator of LPS signaling, the authors investigated the possible involvement of ATF-3 in the anti-inflammatory effects of berberine. It was found berberine concentration-dependently induced the expressions of ATF-3 at the mRNA and protein levels and concomitantly suppressed the LPS-induced productions of proinflammatory cytokines ($TNF-{\alpha}$, IL-6, and $IL-1{\beta}$). In addition, ATF-3 knockdown abolished the inhibitory effects of berberine on LPS-induced proinflammatory cytokine production, and prevented the berberine-induced suppression of MAPK phosphorylation, but had little effect on AMPK phosphorylation. On the other hand, the effects of berberine, that is, ATF-3 induction, proinflammatory cytokine inhibition, and MAPK inactivation, were prevented by AMPK knockdown, suggesting ATF-3 induction occurs downstream of AMPK activation. The in vivo administration of berberine to mice with LPS-induced endotoxemia increased ATF-3 expression and AMPK phosphorylation in spleen and lung tissues, and concomitantly reduced the plasma and tissue levels of proinflammatory cytokines. These results suggest berberine has an anti-inflammatory effect on macrophages and that this effect is attributable, at least in part, to pathways involving AMPK activation and ATF-3 induction.

Kahweol from Coffee Induces Apoptosis by Upregulating Activating Transcription Factor 3 in Human Colorectal Cancer Cells

  • Park, Gwang Hun;Song, Hun Min;Jeong, Jin Boo
    • Biomolecules & Therapeutics
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    • 제25권3호
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    • pp.337-343
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    • 2017
  • Kahweol as a coffee-specific diterpene has been reported to induce apoptosis in human cancer cells. Although some molecular targets for kahweol-mediated apoptosis have been elucidated, the further mechanism for apoptotic effect of kahweol is not known. Activating transcription factor 3 (ATF3) has been reported to be associated with apoptosis in colorectal cancer. The present study was performed to investigate the molecular mechanism by which kahweol stimulates ATF3 expression and apoptosis in human colorectal cancer cells. Kahweol increased apoptosis in human colorectal cancer cells. It also increased ATF3 expression through the transcriptional activity. The responsible cis-element for ATF3 transcriptional activation by kahweol was CREB located between -147 to -85 of ATF3 promoter. ATF3 overexpression increased kahweol-mediated cleaved PARP, while ATF3 knockdown attenuated the cleavage of PARP by kahweol. Inhibition of ERK1/2 and $GSK3{\beta}$ blocked kahweol-mediated ATF3 expression. The results suggest that kahweol induces apoptosis through ATF3-mediated pathway in human colorectal cancer cells.

Porphyromonas gingivalis lipopolysaccharide stimulates vascular smooth muscle cell migration through signal transducer and activator of transcription 3-mediated matrix metalloproteinase-9 expression

  • Kim, Yeon;Park, Joo-Yeon;Park, Hyun-Joo;Kim, Mi-Kyoung;Kim, Yong-Il;Bae, Soo-Kyung;Kim, Hyung Joon;Bae, Moon-Kyoung
    • International Journal of Oral Biology
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    • 제44권1호
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    • pp.20-26
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    • 2019
  • Periodontal diseases have been associated with the development of cardiovascular diseases. Accumulating evidences have indicated that Porphyromonas gingivalis, a major periodontopathic pathogen, plays a critical role in the pathogenesis of atherosclerosis. In the present study, we demonstrated that P. gingivalis lipopolysaccharide (LPS) increases the mRNA and protein expression of matrix metalloproteinase-9 (MMP-9) in rat vascular smooth muscle cells. We showed that the MMP-9 expression induced by P. gingivalis LPS is mediated by the activation of signal transducer and activator of transcription 3 (STAT3) in vascular smooth muscle cells. Furthermore, the inhibition of STAT3 activity reduced P. gingivalis LPS-induced migration of vascular smooth muscle cells. Overall, our findings indicate that P. gingivalis LPS stimulates the migration of vascular smooth muscle cells via STAT3-mediated MMP-9 expression.

Diarylpropionitrile inhibits melanogenesis via protein kinase A/cAMP-response element-binding protein/microphthalmiaassociated transcription factor signaling pathway in α-MSH-stimulated B16F10 melanoma cells

  • Lee, Hyun Jeong;An, Sungkwan;Bae, Seunghee;Lee, Jae Ho
    • The Korean Journal of Physiology and Pharmacology
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    • 제26권2호
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    • pp.113-123
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    • 2022
  • Diarylpropionitrile (DPN), a selective agonist for estrogen receptor β (ERβ), has been reported to regulate various hormonal responses through activation of ERβ in tissues including the mammary gland and brain. However, the effect of DPN on melanogenesis independent of ERβ has not been studied. The aim of this study is to examine the possibility of anti-melanogenic effect of DPN and its underlying mechanism. Melanin contents and cellular tyrosinase activity assay indicated that DPN inhibited melanin biosynthesis in alpha-melanocyte stimulating hormone-stimulated B16F10 melanoma cell line. However, DPN had no direct influence on in vitro tyrosinase catalytic activity. On the other hand, 17β-estradiol had no effect on inhibition of melanogenesis, suggesting that the DPN-mediated suppression of melanin production was not related with estrogen signaling pathway. Immunoblotting analysis showed that DPN down-regulated the expression of microphthalmia-associated transcription factor (MITF), a central transcription factor of melanogenesis and its down-stream genes including tyrosinase, tyrosinase-related protein (TRP)-1, and TRP-2. Also, DPN attenuated the phosphorylation of protein kinase A (PKA) and cAMP-response element-binding protein (CREB). Additionally, DPN suppressed the melanin synthesis in UVB-irradiated HaCaT conditioned media culture system suggesting that DPN has potential as an anti-melanogenic activity in physiological conditions. Collectively, our data show that DPN inhibits melanogenesis via downregulation of PKA/CREB/MITF signaling pathway.

Anti-inflammatory Activities of Chopi (Zanthoxylum piperitum A.P. DC) Essential Oil: Suppression of the Inducible Nitric Oxide Synthase and Cellular Adhesion

  • Lee, Je-Hyuk;Chang, Kyung-Mi;Kim, Gun-Hee
    • Food Science and Biotechnology
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    • 제18권6호
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    • pp.1371-1378
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    • 2009
  • The aim of this study is to elucidate the anti-inflammatory activities of chopi (Zanthoxylum piperitum A.P. DC.) essential oil. Essential oil (EO) of chopi was extracted by steam distillation method, and its major constituents were limonene and geranyl acetate. Chopi-EO decreased approximately 38% of nitrite production, as compared to the lipopolysaccharde (LPS)-induced nitrite production. However, chopi-EO and its components did not quench nitric oxide (NO) chemically in cellfree system, and markedly inhibited approximately 40.4% of inducible nitric oxide synthase (iNOS) mRNA transcription. In addition, the inhibition of E-selectin gene transcription by chopi-EO caused the suppression of cellular adhesion. These results suggest that chopi-EO may exert potential anti-immunological inflammatory activity.

Activating Transcription Factor 3 is a Molecular Target for Apoptotic Effect of Silymarin in Human Colorectal Cancer Cells

  • Eo, Hyun Ji;Park, Gwang Hun;Jeong, Jin Boo
    • 한국자원식물학회지
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    • 제29권3호
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    • pp.281-288
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    • 2016
  • Apoptosis has been regarded as a therapeutic target because apoptosis is typically disturbed in human cancer. Silymarin found in the seeds of the milk thistle (Silybum marianum) has been reported to exert anti-cancer properties through apoptosis. This study was performed to investigate the molecular target for silymarin-mediated apoptosis in human colorectal cancer cells. Silymarin reduced the cell viability and induced an apoptosis in human colorectal cancer cells. ATF3 overexpression increased PARP cleavage by silymarin. Increased ATF3 expression in both protein and mRNA was observed in silymarin-treated cells. In addition, silymarin increased the luciferase activity of ATF3 promoter. Inhibition of JNK and IκK-α blocked silymarin-mediated ATF3 expression. The results suggest that silymarin induces apoptosis through JNK and IκKα-dependent ATF3 expression in human colorectal cancer cells.

Suppression of AP-1 Activity by Tanshinone and Cancer Cell Growth Inhibition

  • 박세연;송지성;이덕근;양철학
    • Bulletin of the Korean Chemical Society
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    • 제20권8호
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    • pp.925-928
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    • 1999
  • The process of transcription is the major point at which gene expression is regulated. The jun and fos families of eukaryotic transcription factor heterodimerize to form complexes capable of binding 5'-TGAGTCA-3'DNA elements (AP-1 binding site). To search for the inhibitors of the jun-fos-DNA complex formation, several natural products extracts were screened and methanol extract of tanshen (the dried roots of Salvia miltiorrhiza Bunge) showed remarkable inhibitory activity. The active compounds of the extracts were purified using re-peated column chromatography and recrystallization. Their structures were identified as tanshinone I and tanshinone IIA. Through the electrophoresis mobility shift assay and cell cytotoxicity test, tanshinone I and tanshinone IIA were identified as inhibitors that suppress not only AP-1 function but also the cell proliferation. Tanshinone I also suppressed the jun-fos-DNA complex formation in TPA-induced NIH 3T3 cells.

연잎 추출물의 항산화 활성 및 멜라노마 세포(B16F10)에서 MITF, TRP-1, TRP-2, tyrosinase의 발현 저해 효과 (Antioxidant Effect of Nelumbo nucifera G. Leaf Extract and Inhibition of MITF, TRP-1, TRP-2, and Tyrosinase Expression in a B16F10 Melanoma Cell Line)

  • 유단희;주다혜;이수연;이진영
    • 생명과학회지
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    • 제25권10호
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    • pp.1115-1123
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    • 2015
  • 본 연구는 연잎 추출물의 미백 화장품 첨가물로서 사용이 가능한지를 연구하였다. 연잎 추출물의 항산화 활성을 측정하게 위해 전자공여능 측정, xanthine oxidase 억제 효과 실험을 실시하였고, 미백활성을 알아보기 위하여 tyrosinase 저해활성을 측정하여 1,000 μg/ml의 농도에서 42.7%의 효과를 나타내었다. 또한 연잎 추출물에 대한 세포생존율을 MTT assay로 측정한 결과 1,000 μg/ml 농도에서 81.61%를 이상의 세포생존율을 확인할 수 있었다. 미백 관련 인자인 MITF, TRP-1, TRP-2 및 tyrosinase의 단백질 발현과 mRNA 발현 억제를 25, 50, 100 μg/ml 농도에서 측정하였다. MITF, TRP-1, TRP-2 및 tyrosinase의 단백질 발현은 100 μg/ml 농도에서 각각 69.6%, 27.7%, 67.3%, 67.8%의 저해 효과를 나타내었고, MITF, TRP-1, TRP-2 및 tyrosinase의 mRNA발현은 100 μg/ml 농도에서 각각 67.5%, 71.4%, 85.7%, 83.6%의 억제를 나타내었다. 이러한 연구결과를 보았을 때, 연잎 추출물이 항산화 및 미백활성에 효과를 나타내었고, 화장품 첨가물로서의 가능성을 확인할 수 있었다.

3T3-L1 전지방세포에서 발효 삼정환의 지방 분화 억제 효과 (Effect of Probiotics-Fermented Samjunghwan on Differentiation in 3T3-L1 Preadipocytes)

  • 송미영;;김호준
    • 한국식품영양과학회지
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    • 제42권1호
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    • pp.1-7
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    • 2013
  • 본 연구에서는 3T3-L1 전지방세포를 이용하여 발효 삼정환의 지방 분화 억제 효과를 확인하고자 하였다. 삼정환을 5가지 주요 유산균으로 각각 발효시킨 후, Oil Red O 염색법으로 지방세포 분화 억제 여부를 알아보고, 이의 기전을 알기 위해서 지방생성에 핵심적인 역할을 하는 transcription factor 및 지질 조절 효소의 유전자 발현량을 비교하여 보았다. Oil Red O 염색 분석에서는 Lactobacillus plantarum, Enterococcus faecium으로 발효한 삼정환에서 지방구 수의 감소를 확인할 수 있었다. 또한 transcription factor로 $C/EPB{\alpha}$, $PPAR{\gamma}$, UCP-2 및 콜레스테롤 조절과 관련된 효소인 HMG-CoA reductase의 4가지 유전자 발현 정도를 분석하였는데, 발효시키지 않은 삼정환의 경우 농도가 $100{\mu}L/mL$ 이상일 때 네 가지 항목에서 억제 효과를 나타냈으며, 발효시켰을 때는 유산균의 종류에 따라 효과 억제효과가 있었는데, Lactobacillus plantarum으로 발효한 삼정환이 효과가 가장 좋은 것으로 나타났다. Lactobacillus plantarum으로 발효한 삼정환은 동일 농도의 발효하지 않은 삼정환과 비교했을 때, Oil Red O 실험에서 염색된 지방구 수가 더욱 감소하였으며, $PPAR{\gamma}$, UCP-2, HMG-CoA reductase의 경우 농도가 $200{\mu}L/mL$일 때 각각 35%, 57%, 54%로 5가지 발효 삼정환 중 가장 높은 억제율을 나타내었다. 이에 지방분화 억제 효과를 가진 삼정환을 발효시키면 그 효과가 더욱 증가하는 것으로 나타났는데, 특히 Lactobacillus plantarum으로 발효한 삼정환은 $PPAR{\gamma}$, UCP-2, HMG-CoA reductase의 유전자 발현조절을 통해 지방 분화를 억제시키는 것으로 밝혀져 발효 삼정환은 항비만 혹은 항고지혈증 약물로 개발 가능성이 있는 것으로 사료된다.

청미래덩굴 잎 물추출물이 처리된 HepG2 세포에서의 포도당흡수기전 연구 (Study of the mechanisms underlying increased glucose absorption in Smilax china L. leaf extract-treated HepG2 cells)

  • 강윤환;김대중;김경곤;이성미;최면
    • Journal of Nutrition and Health
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    • 제47권3호
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    • pp.167-175
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    • 2014
  • 본 연구에는 SCLE를 이용하여 시도된 바가 없는 glucose uptake 유도 실험을 수행하여 HepG2 세포에서 포도당흡수가 증가함을 확인하였다. 또한 이런 포도당의 흡수는 HNF-$1{\alpha}$라는 transcription factor의 활성화를 통해 GLUT-2의 발현을 증가시키기 때문인 것을 실험적으로 증명하였다. 뿐만 아니라 Bacillus stearothermophilus 유래의 GK를 이용하여 활성을 측정한 결과 SCLE가 직접적으로 GK를 활성화하여 포도당의 인산화에 영향을 주는 것을 확인할 수 있었으며 그 실험결과들은 Fig. 8에서 도식화 하였다. 본 연구를 통해 SCLE가 ${\alpha}$-glucosidase inhibition 활성에 의한 혈당의 개선과 당뇨예방 효과뿐만 아니라 다양한 세포내 기전을 통해 혈당 및 당뇨의 개선을 유도할 수 있음을 확인하였고, 이는 SCLE가 neutraceuticals 소재로서의 개발가치가 높음을 시사한다.