• Molecules and Cells
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• 제25권4호
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• pp.559-565
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• 2008

Members of the TGA family of basic domain/leucine zipper transcription factors regulate defense genes through physical interaction with NON-EXPRESSOR OF PR1 (NPR1). Of the seven TGA family members, TGA4/octopine synthase (ocs)-element-binding factor 4 (OBF4) is the least understood. Here we present evidence for a novel function of OBF4 as a regulator of flowering. We identified CONSTANS (CO), a positive regulator of floral induction, as an OBF4-interacting protein, in a yeast two-hybrid library screen. OBF4 interacts with the B-box region of CO. The abundance of OBF4 mRNA cycles with a 24 h rhythm under both long-day (LD) and short-day (SD) conditions, with significantly higher levels during the night than during the day. Electrophoretic mobility shift assays revealed that OBF4 binds to the promoter of the FLOWERING LOCUS T (FT) gene, a direct target of CO. We also found that, like CO and FT, an OBF4:GUS construct was prominently expressed in the vascular tissues of leaf, indicating that OBF4 can regulate FT expression through the formation of a protein complex with CO. Taken together, our results suggest that OBF4 may act as a link between defense responses and flowering.

• 한국식품영양학회지
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• 제26권3호
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• pp.485-491
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• 2013

본 연구에서는 피로 회복 또는 원기 회복에 효능이 있는 것으로 알려진 홍경천과 홍삼을 이용하여 홍경천-홍삼 복합 발효물의 산화적 손상 억제 효과를 평가하고자 $H_2O_2$로 산화적 스트레스를 유도시킨 C2C12 근육세포에 홍경천-홍삼 복합 발효물의 처리한 후, 세포의 morphology, cell viability 및 항산화 효소들의 유전자 발현 양상을 비교, 분석하였다. 홍경천-홍삼 복합 발효물은 C2C12 근육세포의 cell viability를 유의적으로 증가시켰으며, Cu/Zn-SOD, Mn-SOD 및 GPx 등과 같은 세포내 항산화 효소의 발현을 증가시킬 뿐만 아니라, 근육세포 분화의 주요 전사인자인 Myo D의 발현 또한 증가시키는 것으로 나타났다. 이상의 결과로, 홍경천-홍삼 복합 발효물은 세포내 항산화 효소 시스템을 증가시켜 외부로부터의 산화적 손상에 대한 방어효능을 갖는 것으로 나타났으며, 향후 in vivo 시스템 이용한 추가적인 연구가 수행된다면, 홍경천-홍삼 복합 발효물을 이용한 항피로 건강기능식품의 소재개발이 가능할 것으로 판단된다.

• Journal of Plant Biotechnology
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• 제30권4호
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• pp.323-328
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• 2003

토양 내의 고농도의 염은 심각한 환경스트레스 중의 하나로 농작물의 생산을 감소시킨다. 식물은 염 스트레스로부터 벗어나기 위하여 많은 단백질을 합성한다든지 유전자들의 발현을 조절하는 등 여러 가지 생리, 생화학적인 변화를 일으킨다. 퉁퉁마디는 우리나라에 자생하는 염생식물로 갯벌과 염전주위에서 생육한다. 퉁퉁마디의 생화학적, 분자생물학적 내염성 기구를 이해하기 위하여 differential display방법으로 NaCl에 의하여 발현이 증가되는 cDNA들을 분리하였다. 본 연구에서는 그 중 하나인 ShADL의 특성을 조사하였다. ShADL은fructose-1, 6-bisphosphate aldolase와 높은 유사성을 보였다. 이 유전자는 1293bp길이에 359개의 아미노산으로 구성된 open reading frame을 포함하고 있으며, 이로부터 추정되는 분자량은 39 kDa이었다. ShADL단백질은 애기장대의 aldolase와 86％의 높은 유사성을 나타내었으며 같은 염생식물인 com-mon ice plant의 adolase와는 78％의 유사성을 보였다. Northern 분석결과, ShADL 유전자는 NaCl의 농도가 증가함에 따라 발현량이 급격히 증가하는 것으로 나타났다.

• 동의생리병리학회지
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• 제20권6호
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• pp.1530-1537
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• 2006

Platycodi Radix, the root of Platycodon grandiflorum A. DC (Campanulaceae), commonly known as Doraji in Korea (Chinese name, 'Jiegeng', and Japanese name, 'Kikyo') has been used as an expectorant in traditional Oriental medicine. Extracts from the roots of P. grandiflorum have been reported to have wide ranging health benefits. In Korea, Platycodi Radix is also used as a food and employed as a folk remedy for adult diseases, such as bronchitis, asthma and pulmonary tuberculosis, hyperlipidemia, diabetes, and inflammatory diseases, and as a sedative. Several studies on its chemical and immunopharmacological effects including immunostimulation and antitumor activity have been performed. However, the relevant molecular mechanisms are poorly understood. Platycodi Radix, the root of Platycodon grandiflorum A. DC (Campanulaceae), commonly known as Doraji in Korea (Chinese name, 'Jiegeng', and Japanese name, 'Kikyo') has been used as an expectorant in traditional Oriental medicine. Extracts from the roots of P. grandiflorum have been reported to have wide ranging health bensfits. In Korea, Platycodi Radix is also used as a food and employed as a folk remedy for adult diseases, such as bronchitis, asthma and pulmonary tuberculosis, hyperlipidemia, diabetes, and inflammatory diseases, and as a sedative. Several studies on its chemical and immunopharmacological effects including immunostimulation and antitumor activity have been performed. However, the relevant molecular mechanisms are poorly understood. In the present study, we investigated the effects of an aqueous extract from the roots of P. grandiflorum AEPG) on the cell growth of human lung adenocarcinoma NCI-H460 cells in order to understand its anti-proliferative mechanism. AEPG treatment down-regulated the cyclin D1 expression in both transcriptional and translational levels without alteration of cyclin E. In AEPG-treated cells, the levels of cyclin-dependent kinase (C아) 6 mRNA and protein were significantly inhibited, but the levels of Cdk2 and Cdk4 were slightly inhibited by treatment of AEPG. AEPG treatment induced a marked accumulation of Cdk inhibitors, p16 and p27. However, AEPG treatment did not affect not only retinoblastoma protein (pRB) but also tumor suppressor p53 protein expression. The present results indicated that AEPG-induced inhibition of lung cancer cell proliferation is associated with the blockage of G1 phase progression through induction of Cdk inhibitors such as p16 and p27, and inhibition of cyclin D1 and Cdk6. AEPG exposure, as offered by this study, provides cluse for the mechanism of AEPG action. Taken together, these findings suggest that P. grandiflorum has strong potential for development as an agent for prevention and treatiment against human lung cancer.

• 생명과학회지
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• 제26권7호
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• pp.847-854
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• 2016

Nucleoside adenosine 유도체의 하나인 cordycepin (3′-deoxyadenosine)은 Cordyceps 속에서 유래된 활성 물질 중의 하나로서 항염증, 항산화 및 항암활성을 포함한 다양한 약리학적 효능이 있는 것으로 잘 알려져 있다. 본 연구에서는 AGS 인체 위암세포의 증식에 미치는 cordycepin의 영향과 관련 기전 연구를 시도하였다. Cordycepin의 처리에 따라 AGS 세포의 생존율이 처리 농도 의존적으로 감소되었으며, DNA 단편화 및 flow cytometery 분석에 따른 apoptosis 유발 또한 유의적으로 증가하였음을 확인하였다. 이러한 cordycepin 처리에 따른 AGS 세포의 apoptosis 유도에는 TRAIL, DR5 및 FasL의 mRNA 및 단백질의 발현 증가가 연관되어 있었다. 아울러 cordycepin은 Bcl-2 family 중 pro-apoptotic 인자인 Bax의 발현은 증가시켰으며, anti-apoptotic 인자인 Bcl-2 및 Bcl-xL의 발현은 전사 및 번역 수준에서 억제시켰다. 이러한 현상들은 extrinsic 및 intrinsic apoptosis의 initiator caspase (caspase-8 및 -9) 뿐만 아니라 effector caspase인 caspase-3의 활성과 PARP 단백질의 절단 증가와 연관성이 있었다. 따라서 AGS 세포에서 cordycepin에 의한 apoptosis의 유발은 death receptor 활성과 mitochondria 기능 손상을 포함한 multiple apoptotic pathway가 관여할 것으로 생각된다. 비록 좀 더 세심한 기전 연구의 결과가 뒤따라야 되겠지만, 본 연구의 결과는 cordycepin의 항암작용을 이해하는데 중요한 자료가 될 것이며 향후 수행될 추가 실험을 위한 기초 자료로서 그 가치가 매우 높을 것으로 생각된다.

• Molecules and Cells
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• 제26권4호
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• pp.338-343
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• 2008

An embryonic stem cell is a powerful tool for investigation of early development in vitro. The study of embryonic stem cell mediated neuronal differentiation allows for improved understanding of the mechanisms involved in embryonic neuronal development. We investigated expression profile changes using time course cDNA microarray to identify clues for the signaling network of neuronal differentiation. For the short time course microarray data, pattern analysis based on the quadratic regression method is an effective approach for identification and classification of a variety of expressed genes that have biological relevance. We studied the expression patterns, at each of 5 stages, after neuronal induction at the mRNA level of embryonic stem cells using the quadratic regression method for pattern analysis. As a result, a total of 316 genes (3.1%) including 166 (1.7%) informative genes in 8 possible expression patterns were identified by pattern analysis. Among the selected genes associated with neurological system, all three genes showing linearly increasing pattern over time, and one gene showing decreasing pattern over time, were verified by RT-PCR. Therefore, an increase in gene expression over time, in a linear pattern, may be associated with embryonic development. The genes: Tcfap2c, Ttr, Wnt3a, Btg2 and Foxk1 detected by pattern analysis, and verified by RT-PCR simultaneously, may be candidate markers associated with the development of the nervous system. Our study shows that pattern analysis, using the quadratic regression method, is very useful for investigation of time course cDNA microarray data. The pattern analysis used in this study has biological significance for the study of embryonic stem cells.

• Molecules and Cells
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• 제45권3호
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• pp.134-147
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• 2022

The anti-oxidant enzyme heme oxygenase-1 (HO-1) is known to exert anti-inflammatory effects. From a library of pyrazolo[3,4-d]pyrimidines, we identified a novel compound KKC080096 that upregulated HO-1 at the mRNA and protein levels in microglial BV-2 cells. KKC080096 exhibited anti-inflammatory effects via suppressing nitric oxide, interleukin1β (IL-1β), and iNOS production in lipopolysaccharide (LPS)-challenged cells. It inhibited the phosphorylation of IKK and MAP kinases (p38, JNK, ERK), which trigger inflammatory signaling, and whose activities are inhibited by HO-1. Further, KKC080096 upregulated anti-inflammatory marker (Arg1, YM1, CD206, IL-10, transforming growth factor-β [TGF-β]) expression. In 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridinetreated mice, KKC080096 lowered microglial activation, protected the nigral dopaminergic neurons, and nigral damage-associated motor deficits. Next, we elucidated the mechanisms by which KKC080096 upregulated HO-1. KKC080096 induced the phosphorylation of AMPK and its known upstream kinases LKB1 and CaMKKbeta, and pharmacological inhibition of AMPK activity reduced the effects of KKC080096 on HO-1 expression and LPS-induced NO generation, suggesting that KKC080096-induced HO-1 upregulation involves LKB1/AMPK and CaMKKbeta/AMPK pathway activation. Further, KKC080096 caused an increase in cellular Nrf2 level, bound to Keap1 (Nrf2 inhibitor protein) with high affinity, and blocked Keap1-Nrf2 interaction. This Nrf2 activation resulted in concurrent induction of HO-1 and other Nrf2-targeted antioxidant enzymes in BV-2 and in dopaminergic CATH.a cells. These results indicate that KKC080096 is a potential therapeutic for oxidative stress-and inflammation-related neurodegenerative disorders such as Parkinson's disease.

• Radiation Oncology Journal
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• 제17권4호
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• pp.299-306
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• 1999

목 적 : Ataxia-Telangiectasia (AT) 증은 여러 가지 유전적 결함을 갖는 질병으로 방사선 민감도가 비정상적으로 상승되어 있는 것이 특징이다 AT 환자에서 공통적으로 존재하는 ATM 유전자는 현재까지 방사선 신호전달에 관여하는 것으로 알려진 Pl-3 kinase와 유사한 구조임이 알려져 ATM이 방사선 신호전달경로에 중요한 작용을 할 것으로 추정하게 되었다. 본 연구에서는 AT 세포와 정상세포에 PKCI를 과발현 시킴으로써 방사선 신호전달에 관여하는 PKC를 억제하여 이것이 방사선 민감도에 미치는 영향을 관찰하고, 방사선에 의해 유도되는 early response gene인 c-fos transcription의 차이를 측정하여 ATM과 PKCI에 의한 신호전달이 c-fos 유전자 전사에 미치는 영향을 분석하고자 하였다. 대상 및 방법 : PKCI expression vector를 작제한 후 정상세포인 LM217과 AT세포인 AT5BIVA에 transfection 시킨 후 plasmid의 genomic DNA에 결합된 것은 polymerase chain reaction (PCR) 방법으로 확인하였고 PKCI의 mRNA 발현 여부는 northern blotting으로 확인하였다. 방사선 민감도는 아포토시스로 측정하였으며 PKCI가 과발현된 각 세포주에 5 Gy의 방사선을 조사한 후 48시간에 세포를 모아 TUNEL방법으로 아포토시스 세포의 수를 측정하였다. c-fos 유전자의 전사는 reporter 유전자로 c-fos CAT plsmid를 $\beta$-gal expression vector와 같이 각 세포주에 transfection 시키고 36시간이 지난 후 CAT assay를 하여 activity를 측정하고 동시에 $\beta$-gal assay를 시행하여 transfection 효율을 보정해 주었다. PKCI, Ras의 영향을 보기 위하여는 PKCI, Ras expression vector와 c-fos CAT plasmid를 cotransfection하고 CAT activity로 측정 하였다. 결 과 : 이 실험의 결과 LM과 AT 세포에서 PKCI가 방사선 민감도에 미치는 영향과 c-fos 전사에 미치는 영향을 처음으로 보여주었다. PKCI의 과발현이 LM 세포에서는 방사선 민감도를 증가시켰지만 AT세포에서는 오히려 약간 감소시키는 작용을 나타내었다. c-fos 전사는 AT 세포에서 LM 세포에 비하여 70배 낮게 나타났는데 PKCI가 과발현 됨으로써 LM 에서는 c-fos의 전사가 감소되었지만 AT 세포에서는 영향이 없었다. Ras 단백으로 c-fos를 유도시키고 여기에 PKCI 발현 백터를 contransfection 하면 LM세포에서는 induction 이 감소되었지만 AT 세포에서는 영향이 없었다. 즉 LM과 AT 세포에서의 PKCI에 의한 반응의 차이는 Ras와 관련된 signal transduction pathway라는 것을 알 수 있었다. 결 론 : PKCI는 정상세포에서는 방사선에 의한 세포 손상을 증가시키지만 AT 세포에서는 별 영향을 보이지 않는 것을 알 수 있었으며, 두 세포간의 이러한 차이는 c-fos proto-oncogene의 전사차이로 설명할 수 있겠다. 이러한 차이가 AT 세포의 방사선 민감도의 한 원인일 것으로 생각된다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권23호
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• pp.10407-10412
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• 2015

Background: ${\beta}$-elemene, extracted from herb medicine Curcuma wenyujin has potent anti-tumor effects in various cancer cell lines. However, the activity of ${\beta}$-elemene against glioma cells remains unclear. In the present study, we assessed effects of ${\beta}$-elemene on human glioma cells and explored the underlying mechanism. Materials and Methods: Human glioma U87 cells were used. Cell proliferation was determined with MTT assay and colony formation assay to detect the effect of ${\beta}$-elemene at different doses and times. Fluorescence microscopy was used to observe cell apoptosis with Hoechst 33258 staining and change of glioma apoptosis and cell cycling were analyzed by flow cytometry. Real-time quantitative PCR and Western-blotting assay were performed to investigated the influence of ${\beta}$-elemene on expression levels of Fas/FasL, caspase-3, Bcl-2 and Bax. The experiment was divided into two groups: the blank control group and ${\beta}$-elemne treatment group. Results: With increase in the concentration of ${\beta}$-elemene, cytotoxic effects were enhanced in the glioma cell line and the concentration of inhibited cell viability ($IC_{50}$) was $48.5{\mu}g/mL$ for 24h. ${\beta}$-elemene could induce cell cycle arrest in the G0/G1 phase. With Hoechst 33258 staining, apoptotic nuclear morphological changes were observed. Activation of caspase-3,-8 and -9 was increased and the pro-apoptotic factors Fas/FasL and Bax were upregulated, while the anti-apoptotic Bcl-2 was downregulated after treatment with ${\beta}$-elemene at both mRNA and protein levels. Furthermore, proliferation and colony formation by U87 cells were inhibited by ${\beta}$-elemene in a time and does-dependent manner. Conclusions: Our results indicate that ${\beta}$-elemene inhibits growth and induces apoptosis of human glioma cells in vitro. The induction of apoptosis appears to be related with the upregulation of Fas/FasL and Bax, activation of caspase-3,-8 and -9 and downregulation of Bcl-2, which then trigger major apoptotic cascades.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제32권3호
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• pp.199-206
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• 2010

This study investigated the effects of strontium on osteoblastic phenotypes of cultured human periostealderived cells. Periosteal tissues were harvested from mandible during surgical extraction of lower impacted third molar. Periosteal-derived cells were introduced into cell culture. After passage 3, the periostealderived cells were further cultured for 28 days in an osteogenic induction DMEM medium supplemented with fetal bovine serum, ascorbic acid 2-phosphate, dexamethasone and at a density of $3{\times}10^4$ cells/well in a 6-well plate. In this culture medium, strontium at different concentrations (1, 5, 10, and 100 ${\mu}g$/mL) was added. The medium was changed every 3 days during the incubation period. We examined the cellular proliferation, histochemical detection and biochemical measurements of alkaline phosphatase (ALP), the RT-PCR analysis for ALP and osteocalcin, and von Kossa staining and calcium contents in the periostealderived cells. Cell proliferation was not associated with the addition of strontium in periosteal-derived cells. The ALP activity in the periosteal-derived cells was higher in 5, 10, and 100 ${\mu}g$/ml strontium-treated cells than in untreated cells at day 14 of culture. Among the strontium-treated cells, the ALP activity was appreciably higher in 100 ${\mu}g$/ml strontium-treated cells than in 5 and 10 ${\mu}g$/ml strontium-treated cells. The levels of ALP and osteocalcin mRNA in the periosteal-derived cells was also higher in strontium-treated cells than in untreated cells at day 14 of culture. Their levels were increased in a dose-dependent manner. Von Kossa-positive mineralization nodules were strongly observed in the 1 ${\mu}g$/ml strontium-treated cells at day 21 and 28 of culture. The calcium content in the periosteal-derived cells was also higher in 1 ${\mu}g$/ml strontium-treated cells at day 28 of culture. These results suggest that low concentration of strontium stimulates the osteoblastic phenotypes of more differentiated periosteal-derived cells, whereas high concentration of strontium stimulates the osteoblastic phenotypes of less differentiated periosteal-derived cells. The effects of strontium on osteoblastic phenotypes of periosteal-derived cells appear to be associated with differentiation-extent.