• BMB Reports
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• 제55권8호
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• pp.401-406
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• 2022

Ahnak, a large protein first identified as an inhibitor of TGF-β signaling in human neuroblastoma, was recently shown to promote TGF-β in some cancers. The TGF-β signaling pathway regulates cell growth, various biological functions, and cancer growth and metastasis. In this study, we used Ahnak knockout (KO) mice that underwent a 70% partial hepatectomy (PH) to investigate the function of Ahnak in TGF-β signaling during liver regeneration. At the indicated time points after PH, we analyzed the mRNA and protein expression of the TGF -β/Smad signaling pathway and cell cycle-related factors, evaluated the cell cycle through proliferating cell nuclear antigen (PCNA) immunostaining, analyzed the mitotic index by hematoxylin and eosin staining. We also measured the ratio of liver tissue weight to body weight. Activation of TGF-β signaling was confirmed by analyzing the levels of phospho-Smad 2 and 3 in the liver at the indicated time points after PH and was lower in Ahnak KO mice than in WT mice. The expression levels of cyclin B1, D1, and E1; proteins in the Rb/E2F transcriptional pathway, which regulates the cell cycle; and the numbers of PCNA-positive cells were increased in Ahnak KO mice and showed tendencies opposite that of TGF-β expression. During postoperative regeneration, the liver weight to body weight ratio tended to increase faster in Ahnak KO mice. However, 7 days after PH, both groups of mice showed similar rates of regeneration, following which their active regeneration stopped. Analysis of hepatocytes undergoing mitosis showed that there were more mitotic cells in Ahnak KO mice, consistent with the weight ratio. Our findings suggest that Ahnak enhances TGF-β signaling during postoperative liver regeneration, resulting in cell cycle disruption; this highlights a novel role of Ahnak in liver regeneration. These results provide new insight into liver regeneration and potential treatment targets for liver diseases that require surgical treatment.

• Molecules and Cells
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• 제40권3호
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• pp.211-221
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• 2017

Transforming growth factor ${\beta}1$ $(TGF{\beta}1)/Smad4$ signaling plays a pivotal role in maintenance of the dynamic balance between bone formation and resorption. The microRNA miR-155 has been reported to exert a significant role in the differentiation of macrophage and dendritic cells. The goal of this study was to determine whether miR-155 regulates osteoclast differentiation through $TGF{\beta}1/Smad4$ signaling. Here, we present that $TGF{\beta}1$ elevated miR-155 levels during osteoclast differentiation through the stimulation of M-CSF and RANKL. Additionally, we found that silencing Smad4 attenuated the upregulation of miR-155 induced by $TGF{\beta}1$. The results of luciferase reporter experiments and ChIP assays demonstrated that $TGF{\beta}1$ promoted the binding of Smad4 to the miR-155 promoter at a site located in 454 bp from the transcription start site in vivo, further verifying that miR-155 is a transcriptional target of the $TGF{\beta}1/Smad4$ pathway. Subsequently, TRAP staining and qRT-PCR analysis revealed that silencing Smad4 impaired the $TGF{\beta}1$-mediated inhibition on osteoclast differentiation. Finally, we found that miR-155 may target SOCS1 and MITF to suppress osteoclast differentiation. Taken together, we provide the first evidence that $TGF{\beta}1/Smad4$ signaling affects osteoclast differentiation by regulation of miR-155 expression and the use of miR-155 as a potential therapeutic target for osteoclast-related diseases shows great promise.

• Molecules and Cells
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• 제40권12호
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• pp.906-915
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• 2017

Impairment of wound healing is a common problem in individuals with diabetes. Adiponectin, an adipocyte-derived cytokine, has many beneficial effects on metabolic disorders such as diabetes, obesity, hypertension, and dyslipidemia. C1q/TNF-Related Protein 9 (CTRP9), the closest paralog of adiponectin, has been reported to have beneficial effects on wound healing. In the current study, we demonstrate that CTRP9 regulates growth, differentiation, and apoptosis of HaCaT human keratinocytes. We found that CTRP9 augmented expression of transforming growth factor beta 1 ($TGF{\beta}1$) by transcription factor activator protein 1 (AP-1) binding activity and phosphorylation of p38 in a dose-dependent manner. Furthermore, siRNA-mediated suppression of $TGF{\beta}1$ reversed the increase in p38 phosphorylation induced by CTRP9. siRNA-mediated suppression of $TGF{\beta}1$ or p38 significantly abrogated the effects of CTRP9 on cell proliferation and differentiation while inducing apoptosis, implying that CTRP9 stimulates wound recovery through a $TGF{\beta}1$-dependent pathway in keratinocytes. Furthermore, intravenous injection of CTRP9 via tail vein suppressed mRNA expression of Ki67 and involucrin whereas it augmented $TGF{\beta}1$ mRNA expression and caspase 3 activity in skin of type 1 diabetes animal models. In conclusion, our results suggest that CTRP9 has suppressive effects on hyperkeratosis, providing a potentially effective therapeutic strategy for diabetic wounds.

• Molecules and Cells
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• 제24권2호
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• pp.283-287
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• 2007

$TGF-{\beta}1$ induces Ig germ-line ${\alpha}$ ($GL{\alpha}$) transcription and subsequent class switching recombination (CSR) to IgA. In the present study, we investigated the roles of two E3-ubiquitin ligases, Smurfs (HECT type) and Arkadia (RING finger type) on $TGF{\beta}1$-induced IgA CSR. We found that over-expression of Smurf1 and Smurf2 decreased $TGF{\beta}1$-induced $GL{\alpha}$ promoter activity and strengthened the inhibitory effect of Smad7 on the promoter activity. Further, over-expression of Smurf1 and Smurf2 decreased both Smad3/4-mediated and Runx3-mediated $GL{\alpha}$ promoter activities, suggesting that the Smurfs can down-regulate the major $TGF-{\beta}1$ signaling pathway and decrease $GL{\alpha}$ gene expression. In parallel, the over-expressed Smurf1 decreased the expression of endogenous IgA CSR-predictive transcripts ($GLT_{\alpha}$, $PST_{\alpha}$, and $CT_{\alpha}$) and also $TGF{\beta}1$-induced IgA secretion. Conversely over-expression of Arkadia abolished the inhibitory effect of Smad7 on $TGF{\beta}1$-induced $GLT_{\alpha}$ expression and IgA secretion. Similar results were obtained in the presence of over-expressed Smad7 and Smurf1. These results indicate that Arkadia can amplify $TGF{\beta}1$-induced IgA CSR by degrading Smad7, which interacts with Smurf1. We conclude that Smurf and Arkadia have opposite roles in the regulation of $TGF{\beta}1$-induced IgA isotype expression.

• 생약학회지
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• 제48권2호
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• pp.148-154
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• 2017

Crinum asiaticum var. japonicum and its active component, norgalanthamine have been reported to have hair growth-promoting effect via the proliferation of dermal papilla cells. In this study, we investigated the other mechanisms of C. asiaticum extract var. japonicum and norgalanthamine on the hair growth. The C. asiaticum var. japonicum extract inhibited $5{\alpha}$-reductase activity by 16%, which converts testosterone to dihydrotestosterone (DHT), a main cause of androgenetic alopecia, whereas the C. asiaticum var. japonicum extract didn't function as an opener of the $K_{ATP}$ channel. On the other hand, we examined whether norgalanthamine can inhibit transforming growth factor-${\beta}$ (TGF-${\beta}$) signal pathway, which is essential in the regression induction of hair growth. Norgalanthamine inhibited the phosphorylation of Smad2/3 on TGF-${\beta}1$-induced canonical pathway in human keratinocyte HaCaT cells. These results suggested that the C. asiaticum var. japonicum extract and norgalanthamine had the potential to influence hair growth through the inhibition of $5{\alpha}$-reductase activity and TGF-${\beta}1$-induced canonical pathway.

• 생명과학회지
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• 제22권10호
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• pp.1371-1377
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• 2012

신장섬유화는 내 외부적인 요인들에 의해 발생하며, 그 요인들에 의해 염증이 생기고 지속적인 손상이 일어날 경우 신기능의 상실이 유발된다. 또한 신장섬유화는 세포 외 기질의 과다축적, TGF-${\beta}$나, TNF-${\alpha}$, IL-1과 같은 사이 토카인에 의해 발생하며, TGF-${\beta}$는 신장 섬유화의 과정과 Type I collagen과 fibronectin, PAI-1을 포함한 섬유화 관련 인자들의 발현 유도에 중요한 역할을 한다. 본 연구에서는 TGF-${\beta}$를 처리한 신장섬유화 유도 모델에서 Moringa oleifera Lam 추출물에 대한 섬유화 관련 인자들의 영향을 확인하였다. 실험 결과 TGF-${\beta}$로 유도된 신장 섬유화 세포에서 모링가 추출물이 fibronectin, Type I collagen과 PAI-1의 단백질 및 mRNA 발현을 저해하였으며, 모링가 추출물 중 모링가 뿌리추출물이 가장 영향이 있는 것으로 확인 되었다. 모링가 뿌리추출물이 어떠한 기전을 통하여 섬유화 관련 인자들의 발현을 조절하는지 알아보기 위한 TGF-${\beta}$로 유도된 $T{\beta}RII$ 및 그 하위 기전의 인산화 정도를 확인한 실험에서 모링가 뿌리추출물이 TGF-${\beta}$로 유도된 $T{\beta}RII$과 그 하위기전의 Smad4, ERK의 인산화를 저해하였다. 그러나 TGF-${\beta}$에 의해 유도된 JNK와 p38, PI3K/AKT의 인산화에는 영향이 없었다. 따라서 모링가 뿌리추출물이 TGF-${\beta}$로 유도된 신장 섬유아세포에서 $T{\beta}RII$와 그 하위 기전인 Smad4, ERK를 통해서 Type I collagen 과 fibronectin, PAI-1의 발현을 조절하여 섬유화를 저해 한다는 것을 예상할 수 있다. 결론적으로 모링가 뿌리추출물이 섬유화 치료 및 완화에 좋은 물질이 될 수 있을 것으로 생각된다.

• Journal of Oral Medicine and Pain
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• 제26권1호
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• pp.39-50
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• 2001

In order to investigate the effect of Transforming growth factor ${\beta}1$(below TGF-${\beta}1$) and osteogenic protein-1(below Op-1) onto the myogenic differentiation, C2C12 satellite myoblastic cell line was cultured and treated with both growth factors. At first morphological changes with microscopical examination were examined, and isolated total RNA to analyse mRNA expression of bone marker proteins, muscle regulatory proteins, TGF-${\beta}$ receptor and their ligands by Northern blot analysis. And cellular proliferative inducibility of both growth factors was also tested to C2C12 cells. Incubating the cell with $5ng/m{\ell}$ of TGF-${\beta}1$ until 4 days almost inhibited multinucleated myotube formation expressing muscular regulatory proteins, and induced decreasing Id proteins. However, no osteoblastic phenotypes was induced by TGF-${\beta}1$ in C2C12 cells. The mRNA expression of TGF-${\beta}$ receptors with TGF-${\beta}1$ was conversed after 48 hours cultured. Type I TGF-${\beta}$ receptor was seemed to play a role in negative signalling for inhibition of myogenic differentiation. OP-1 dose dependently induced ALP activity, osteopontine production and bone sialoprotein production at concentrations above $100ng/m{\ell}$ and osteocalcin production at concentrations above $300ng/m{\ell}$. The concentration of OP-1 required to induce these osteoblastic phenotypes was the same as that required to almost completely inhibit myotube formation. Incubation with above $100ng/m{\ell}$ OP-1 suppressed the expression of mRNA for muscular egulatory proteins from 2 days after incubation. Expression of Id-1, 2, 3 mRNA were stimulated by OP-1 at concentration above $300ng/m{\ell}$. When C2C12 cells were treated with both growth factors, TGF-${\beta}1$ potentiated the inhibitory effect of OP-1 on myotube formation and expression of mRNA for myogenin at 12 days. And TGF-${\beta}1$ reduced osteocalcin and bone sialoprotein production induced by OP-1 at 12 days in C2C12 cells. Both growth factor had no mitogenic effect. These results indicate that OP-1 converts the differentiation pathway of C2C12 myoblasts into that of osteoblastic lineage cells and it's not heritable, but TGF-${\beta}1$ does not and has reversible inhibitory activity on the myogenic differentiation. TGF-${\beta}1$ and OP-1 play a role in myogenic differentiation via different mechanism between them.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제33권3호
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• pp.199-203
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• 2007

Several matrix metalloproteinases (MMPs) have been shown to play an important role in the invasion and metastasis of oral squamous cell carcinoma (OSCC). The members of the TGF-$\beta$ signaling pathway are being considered as predictive biomarkers for progressive tumorigenesis and molecular targets for the prevention and the treatment of cancer and metastasis. The aim of the present study was to find the clinical significance of the expression of TGF-${\beta}1$ and MMP-2 related to the regional lymph node metastasis in OSCC. This study included 76 cases of primary OSCC, of which 42 cases showed regional lymph node metastases. Immunohistochemistry was used for the localization of protein. The relation between the expression of each protein and clinical variables was statistically evaluated. In results, the expression of TGF-${\beta}1$ both main mass with lymph node metastasis and without lymph node metastasis was found not to be statistically significant (p>0.05). The expression of MMP-2 was found to be statistically significant related to regional lymph node metastasis (p<0.05). When compared the expression in the metastatic lymph node, TGF-${\beta}1$ was significantly highly expressed than MMP-2 (p<0.05). In conclusion, the expression of MMP-2 was significantly elevated in patients with lymph node metastasis as compared to the patients without lymph node metastasis, which could be useful in predicting the risk of lymph node metastasis in OSCC.

• BMB Reports
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• 제50권8호
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• pp.429-434
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• 2017

Endometriosis is the abnormal growth of endometrial cells outside the uterus, causing pelvic pain and infertility. Furthermore, adhesion of endometrial tissue fragments to pelvic mesothelium is required for the initial step of endometriosis formation outside uterus. $TGF-{\beta}1$ and adhesion molecules importantly function for adhesion of endometrial tissue fragments to mesothelium outside uterus. However, the function of $TGF-{\beta}1$ on the regulation of adhesion molecule expression for adhesion of endometrial tissue fragments to mesothelium has not been fully elucidated. Interestingly, transforming growth factor ${\beta}1$ ($TGF-{\beta}1$) expression was higher in endometriotic epithelial cells than in normal endometrial cells. The adhesion efficiency of endometriotic epithelial cells to mesothelial cells was also higher than that of normal endometrial cells. Moreover, $TGF-{\beta}1$ directly induced the adhesion of endometrial cells to mesothelial cells through the regulation of integrin of ${\alpha}V$, ${\alpha}6$, ${\beta}1$, and ${\beta}4$ via the activation of the $TGF-{\beta}1/TGF-{\beta}RI/Smad2$ signaling pathway. Conversely, the adhesion of $TGF-{\beta}1-stimulated$ endometrial cells to mesothelial cells was clearly reduced following treatment with neutralizing antibodies against specific $TGF-{\beta}1-mediated$ integrins ${\alpha}V$, ${\beta}1$, and ${\beta}4$ on the endometrial cell membrane. Taken together, these results suggest that $TGF-{\beta}1$ may act to promote the initiation of endometriosis by enhancing integrin-mediated cell-cell adhesion.

• Tuberculosis and Respiratory Diseases
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• 제45권4호
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• pp.846-860
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• 1998

연구배경: 내독소는 생체 내에서 단구와 내피세포에 강한 자극을 주나 호중구, 림프구, 호염기구, 섬유모세포 등 여러 세포에도 자극효과가 있어 염증반응이 시작된다. 그중 대식세포는 내독소의 자극을 받아 활성화되면 interleukin-1 (IL-1), IL-6, tumor necrosis factor-alpha (TNF-$\alpha$)를 분비하여 조직손상을 일으킨다. 내독소의 작용기전은 CD14 의존성 경로와 비의존성 경로의 두 개로 나뉘어진다. 체내로 들어온 내독소는 혈청 내에서 내독소 운반에 관여하는 LPS-binding protein(LBP)과 결합하여 혈중내에서 세포와 결합되거나 조직으로 이동되어 조직내 세포와 결합하게 된다. 그러나 고농도의 LPS는 CD14항원에 비의존적으로 대식세포를 자극 할 수 있는 것으로 알려져 있다. 현재까지 LPS자극에 의한 대식세포의 CD14 항원 의존성 IL-1, IL-6, TNF-$\alpha$의 형성과정은 많이 밝혀져 있으나, 내독소에 의한 TGF-$\beta$의 형성 여부는 밝혀져 있지 않으며, CD14 항원 비의존성으로 IL-1, IL-6, TNF-$\alpha$ TGF-$\beta$가 형성되는 과정도 별로 밝혀져 있지 않다. 본 연구에서는 혈청이 없는 상태 (LBP가 없는 상태)에서, 즉 LPS 자극시 LBP-CD14 비의존성으로 말초혈액단핵구에서 형성된 proinflammatory cytokines인 IL-1, IL-6, TNF-$\alpha$과 섬유화 cytokine인 TGF-$\beta$의 생성유무를 규명하고자 하였다. 방 법: 정상인의 헤파린 처리된 말초혈액정맥혈을 비중 1.077의 Ficoll-Hypaque 용액 위에 중첩시킨 후 500g에서 30분간 원심분리하여 말초혈액단핵구를 얻었다. 분리된 말초혈액단핵구를 우태아혈청이 없는 RPMI에 부유시킨 후 $37^{\circ}C$, 5% $CO_2$ 보온기에서 0.1 ${\mu}g$, 1 ${\mu}g$, 10 ${\mu}g$, 100 ${\mu}g/ML$의 LPS와 1, 2, 4, 8, 12, 24, 48 시간 혼합 배양 후 상층액을 분리하여 IL-6, TNF-$\alpha$, TGF-$\beta$의 측정 cytokines의 양을 bioassay로 측정하였다. 세포층은 slide에 고정시킨 후 단 클론 항체를 이용한 이중 면역조직화학염색법과 RNA probe를 이용한 in situ hybridization에 이용하였다. 결 과: 실험사약내 내독소 존재 여부에 대한 검증결과 내독소 함유량은 10 ng/mL 이하로 되어 있어 본 실험에서는 10 ng/mL 이상의 농도로 실험을 하였기 때문에 오염된 내독소는 실험에 영향이 없었을 것으로 사료되었다. 말초혈액단핵구에서 LPS 자극에 의하여 IL-6는 1시간째부터 형성되기 시작하였으며 96 시간까지 지속적으로 상승하였고 LPS용량의존성으로 형성됨을 알 수 있었다. TNF-$\alpha$는 LPS 자극 4시간째부터 상승하기 시작하여 시간이 갈수록 생성양은 증가하며 72 시간째까지 지속적으로 형성되었다. TGF-$\beta$형성도 LPS 용량에 의존성을 보이며 8시간째 일차로 TGF-$\beta$의 형성이 증가 한 후 12 시간째는 오히려 감소하였다가 시간이 지남에 따라 다시 증가하여 2차로 96 시간에 최대 형성을 보였다. 각각 cytokine의 24시간째 생성양은 IL-6의 경우 $1{\times}10^5/mL$의 말초혈액단핵구에서 10 ${\mu}g/mL$의 LPS에 의해서 19.8 ng 이 생성되었고 LPS 자극이 없는 상태의 자연생성능도 3.2 ng이었으며, $1{\times}10^6/mL$의 말초혈액단핵구에 의해서 자연 생성양은 증가하여 24시간째에 0.38 ng/mL, 10명/mL의 농도에서 24시간째 4.1 ng/mL의 TNF-$\alpha$의 생성능을 보였다. TGF-$\beta$의 경우 $2{\times}10^6/mL$의 말초혈액단핵구에 의하여 34.4 pg/mL가 생성되었고 자연생성능은 5.2 pg/mL의 생성농을 보였다. 말초혈액단핵구의 IL-1$\beta$, IL-6, TNF-$\alpha$, TGF-$\beta$ 단백과 m-RNA 발현 IL-1$\beta$, IL-6, TNF-$\alpha$단백은 주로 단구세포에서, TGF-$\beta$ 단백은 단구세포와 림프구에서 발현되었으며, CD14항원 발현과는 상관이 없었다. TNF-$\alpha$, IL-1$\beta$, IL-6, TGF-$\beta$ m-RNA 양성세포는 주로 세포질이 풍부한 것으로 보아 단구세포로 사료되었다. TGF-$\beta$의 경우 단구세포외에도 세포질이 적은 림프구에서도 약하게 양성반응을 보여 링프구에서도 분비될 가능성을 보여 주었다. 결 론: 내독소로 말초혈액 단핵구를 자극시 IL-6, TNF-$\alpha$는 조기에 분비되기 시작하며 TGF-$\beta$는 후기에 분비되기 시작하여 96시간까지 지속적으로 분비된다. 주 분비세포는 IL-1$\beta$, IL-6, TNF-$\alpha$의 경우 단구세포가 되며 TGF-$\beta$도 단구세포가 주세포가 되나 림프구도 분비에 관여한다.