• Nutrition Research and Practice
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• 제4권4호
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• pp.276-282
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• 2010

The principal objective of this study was to evaluate the chemopreventive and therapeutic effects of a combination of all-trans-retinoic acid (RA) and knockdown of delta-like 1 homologue (Drosophila) (DLK1) on neuroblastoma, the most common malignant disease in children. As unfavorable neuroblastoma is poorly differentiated, neuroblastoma cell was induced differentiation by RA or DLK1 knockdown. Neuroblastoma cells showed elongated neurite growth, a hallmark of neuronal differentiation at various doses of RA, as well as by DLK1 knockdown. In order to determine whether or not a combination of RA and DLK1 knockdown exerts a greater chemotherapeutic effect on neuroblastoma, cells were incubated at 10 nM RA after being transfected with SiRNA-DLK1. Neuronal differentiation was increased more by a combination of RA and DLK1 knockdown than by single treatment. Additionally, in order to assess the signal pathway of neuroblastoma differentiation induced by RA and DLK1 knockdown, treatment with the specific MEK/ERK inhibitors, U0126 and PD 98059, was applied to differentiated neuroblastoma cells. Differentiation induced by RA and DLK1 knockdown increased ERK phosphorylation. The MEK/ERK inhibitor U0126 completely inhibited neuronal differentiation induced by both RA and DLK1 knockdown, whereas PD98059 partially blocked neuronal differentiation. After the withdrawal of inhibitors, cellular differentiation was fully recovered. This study is, to the best of our knowledge, the first to demonstrate that the specific inhibitors of the MEK/ERK pathway, U0126 and PD98059, exert differential effects on the ERK phosphorylation induced by RA or DLK1 knockdown. Based on the observations of this study, it can be concluded that a combination of RA and DLK1 knockdown increases neuronal differentiation for the control of the malignant growth of human neuroblastomas, and also that both MEK1 and MEK2 are required for the differentiation induced by RA and DLK1 knockdown.

• 한국발생생물학회지:발생과생식
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• 제4권2호
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• pp.137-145
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• 2000

포유류 원시난포의 분화에는 뇌하수체에서 분비되는 gonadotropins 외에도 다양한 성장인자들 뿐 아니라 스테로이드호르몬 등이 관여하며, 난황낭에서 기원된 생식세포들과 중신에서부터 유입되는 기질세포들의 복잡한 상호작용에 의해 이루어진다. 특히 사람의 경우 태아기에 분화가 시작된 원시난포들은 성장을 개시한 후 배란이 되거나 혹은 폐쇄되어 난소에서 제거되는데, 일부 원시난포는 성장이 개시되기까지 50년 이상 원시난포의 상태로 유지된다. 그러나 원시난포의 분화 및 성장정지, 성장개시의 기전에 관하여는 현재까지 정확하게 밝혀져 있지 않다. 본 논문에서는 태아 및 신생아의 난소에서 gonadotrorin의 수용체, 성장인자와 성장인자 수용체, 그리고 스테로이드호르몬 수용체의 발현을 조사하였다. 이 결과들을 바탕으로 사람 원시난포의 형성, 성장정지를 조절하는 기전 그리고 원시난포의 성장개시에 영향을 미치는 요인을 알아보았다.

• Journal of Animal Science and Technology
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• 제50권4호
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• pp.475-484
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• 2008

본 연구는 retinoic acid(RA)가 돼지지방전구세포의 분화와 유전자 발현에 미치는 영향을 구명하기 위해서 수행하였다. 지방전구세포는 갓난 돼지의 등지방에서 분리했으며 RA는 배양중인 세포에 4일 동안 처리하였다. 배양중인 세포에서 RNA를 추출한 후 14,688개의 유전자가 부착되어 있는 cDNA microarray와 혼성화 하여 유전자 발현 양상을 분석하였다. 지방전구세포의 분화는 GPDH의 활성도에 의해 측정했다. RA는 돼지지방전구세포의 분화를 78% 억제했다. Retinoic acid 처리에 의해 지질 대사에 관계된 유전자를 포함하여 특히 sphin- gomyelin phosphodiesterase, apolipoprotein R precursor, growth factor receptor-bound protein 14, retinoic receptor RXR gamma의 발현이 증가 되었다. 그리고 세포 성장에 중요 역할을 하는 vascular endothelial growth factor D precursor, growth hormone receptor precursor의 유전자의 발현이 감소되었다. 이러한 결과는, RA가 성장촉진인자 또는 성장호르몬 수용체의 조절을 통해서 돼지 지방전구세포의 분화를 억제함을 나타낸다.

• BMB Reports
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• 제30권4호
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• pp.285-291
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• 1997

It is becoming increasingly evident that significant changes in gene expression occur during the course of neuronal differentiation. Thus, it should be possible to gain information about the biochemical events by identifying differentially expressed genes in neuronal differentiation The PC12 cell line is a useful model system to investigate the molecular mechanism underlying neuronal differentiation and has been used extensively for the study of the molecular events that underlie the biological actions of nerve growth factor (NGF). In this study, we report an application of the recently described mRNA differential display method to analyze differential gene expression during neuronal differentiation. Using this technique, we have identified several cDNA tags expressed differentially during neuronal differentiation. Interestingly, one of these clones was cytochrome c oxidase subunit I (COX I) gene. The differential expression of COX I gene was confirmed by Northern blot analysis as well as RT-PCR. Southern blot analysis of the genomic DNA of PC12 cells revealed that COX I is a single gene. Induction of the oxidative enzyme might reflect the energy requirement in neuronal differentiation.

• 대한화장품학회지
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• 제49권1호
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• pp.75-85
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• 2023

본 연구에서는 7 개의 아미노산으로 이루어진 헵타펩타이드의 Lgr5 binding에 따른 인체 모낭 구성 세포의 활성에 대한 영향을 확인하였다. 표면 플라즈몬 공명(surface plasmon resonance, SPR) 시스템을 이용하여 헵타펩타이드가 Lgr5에 결합하는 것을 확인하였다. 인체 모유두세포(human hair follicle dermal papilla cell, HHFDPC)에 헵타펩타이드를 처리한 결과, 농도 의존적인 세포 증식이 나타났으며 β-catenin의 세포 내핵 이동 및 하위 유전자인 LEF1, Cyclin-D1, c-Myc의 발현 증가가 관찰되었다. 그리고 세포 증식 기전 관련 인자인 Akt와 ERK의 인산화 수준이 증가되었으며, 성장인자인 hepatocyte growth factor (HGF), keratinocyte growth factor (KGF), vascular endothelial growth factor (VEGF) 발현이 유도되었다. 또한 인체 모모세포(human hair germinal matrix cell, HHGMC)의 분화 관련 전사 인자와 인체 외모근초세포(human hair outer root sheath cell, HHORSC)의 분화 표지 인자들도 헵타펩타이드 처리 시 높은 발현율을 보였다. 추가적으로 우리는 헵타펩타이드의 인체 모낭줄기세포(human hair follicle stem cell, HHFSC) 분화에 대한 영향을 조사하였다. 그 결과, HHFSC 표지인자들의 mRNA와 단백질 수준이 감소하였고 반면에 분화 표지인자들은 증가하였다. 상기의 결과들은 헵타펩타이드가 인체 모낭 구성 세포에서 Wnt/β-catenin 경로를 촉진시켜 증식 또는 분화를 유도할 수 있음을 보여준다. 이를 토대로 종합해 볼 때, 본 연구의 헵타펩타이드는 모발 성장을 유도하고 탈모 개선에 도움을 줄 수 있는 기능성 원료로 사용될 수 있을 것으로 보인다.

• 대한의생명과학회지
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• 제29권1호
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• pp.26-33
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• 2023

Ziziphus jujuba Mill. (ZJM), a traditional folk medicine and functional food in South Korea and China, has been reported to having pharmacological activities against anti-cancer, anti-oxidative, and anti-obesity. However, the effect of ZJM related to myoblast differentiation has not been known. In this study, we investigated the effects and mechanism of ZJM on myogenic differentiation of C2C12 cells. ZJM promotes myogenic differentiation and elevates the formation of multinucleated myotube compared to the control group. ZJM significantly increased the mRNA and protein expression of MyHC1, myogenin and MyoD in dose- and time-dependent manner. Interestingly, ZJM significantly inhibited the mRNA and protein expression of protein degradation markers, atrogin-1 and MuRF-1, in dose- and time-dependent manner. Taken together, our data suggest that ZJM is a potential functional candidate for muscle growth and strength by promoting myogenic differentiation.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1996년도 춘계학술대회
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• pp.80-104
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• 1996

The development of routine techniques for the isolation and in vitro maintenance of conducting airway epithelial cells in a differentiated state provides an ideal model to study the factors involved in the regulation of the expression of mucocilicary differentiation. Several key factors and conditions have been identified. These factors and conditions include the use of biphasic culture technique to achieve mucociliary differentiation and the use of such stimulators, the thickness of collagen gel substratum, the calcium level, and vitamin A, and such inhibitors, the growth factors EGF and insulin, and steroid hormones, for mucous cell differentiation. Using the defined culture medium, the life cycle of the mucous cell population in vitro was investigated. It was demonstrated that the majority of the mucous cell population in primary cultures is not involved in DNA replication. However, the mucous cell type is capable of self-renewal in culture and this reproduction is vitamin A dependent. furthermore, differentiation from non-mucous cell type to mucous cell type can be demonstrated by adding back a positive regulator such as vitamin A to the “starved” culture. Cell kinetics data suggest that vitamin A-dependent mucous cell differentiation in culture is a DNA replication-independent process and the process is inhibited by TGF-${\beta}$1.

• 미생물학회지
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• 제20권4호
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• pp.173-182
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• 1982

From FGSC 159 strain of Aspergillus nidulans, temperature sensitive mutants that are defective in growth and differentiation have been isolated by N-methyl-N'-nitroN-nitrosoguanidine (NTG) treatment. The optimum concentration of NTG and incubation time to get the highest mutation frequency was $100{\mu}g$ per ml and 1 hour, respectively. The survival frequency was 1%. Among the isolated mutants, five strains that were affected in early steps of differentiation were selected for further studies and named smK, smY, smB, smF, and smZ. The execution point of each mutant was determined and the growing pattern of each mutant at the restrictive temperature was observed under the microscope. Growth of mutant was arrested near at the execution point. From genetic analysis, each temperature-sensitive mutants was thought to have a single recessive gene. The genes of smK, smY, smB, smF, and smZ are linked to the chromosome VII, IV, VIII, I, and VI, respectively. It can be concluded that the genes controlling the differentiation are widely dispersed in the genome. From the results of mutant, smK, it is considered that a single gene can affect a function (functions) which act(s) at two different steps during differentiation.

• Biomolecules & Therapeutics
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• 제8권4호
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• pp.285-292
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• 2000

The effects of the members of the same nuclear receptor superfamily (all-trans retinoic acid (RA), thyroid hormone(T3) or hydrocortisone) on proliferation and differentiation in the SK-N-SH neuroblastoma (NB) cell lines were studied. NB cells were treated with RA, T3, or hydrocortisone at concentration of 10$^{-6}$ M or 10$^{-8}$ M for 3 days or 7 days. RA induced concentration- and time-dependent morphologic differentiation(neurite outgrowth and microtubule-associated protein expression) and growth inhibition in NB cells. Treatment of 10$^{-7}$ M T3 for 7 days increased viability and differentiation of NB cells. Treatment of 10$^{-6}$ M hydrocortisone for 7 days increased viability of NB cells. Although these three effectors are members of the same receptor superfamily, the regulation of brain development may be carried out in a different manner.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2020년도 춘계학술대회
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• pp.90-90
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• 2020

Panax ginseng C.A. Meyer (P. ginseng) is known to exert a wide range of pharmacological effects both in vitro and in vivo. Although studies on ginsenoside, antioxidant activity, and anticancer effect of wild simulated ginseng (WSG) have been conducted, there is little research on the effect of WSG on bone metabolism. In this study, we investigated the potential anti-osteoporotic properties of WSG on the growth and differentiation of MC3T3-E1 cells. WSG significantly increased the viability and proliferation of MC3T3-E1 cells. WSG activated intracellular alkaline phosphatase (ALP) activity in MC3T3-E1 cells. In addition, WSG increased the mineralized nodules in MC3T3-E1 cells. Furthermore, WSG increased the expression of genes such as Runx2, ALP, OPN and OCN associated with osteoblast growth and differentiation in a dose-dependent manner.