• Asian Pacific Journal of Cancer Prevention
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• 제14권11호
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• pp.6305-6309
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• 2013

Background: TIAM2, a Rac guanine nucleotide exchange factor, is closely associated with cell adherence and migration. Here, we aimed to investigate the role of TIAM2 in non-small cell lung cancer (NSCLC) cells. Materials and Methods: A small interference RNA (siRNA) was introduced to silence the expression of TIAM2. Invasion and motility assays were then performed to assess the invasion and motility potential of NSCLC cells. GST-pull down assays were used to detect activation of Rac1. Results: TIAM2 was highly expressed in NSCLC cells. Knockdown of TIAM2 inhibited the invasion and motility, and suppressed activation of Rac1. Further experiments demonstrated that knockdown of TIAM2 could up-regulate the expression of E-cadherin, and down-regulate the expression of MMP-3, Twist and Snail. Conclusions: Our data suggest that TIAM2 can promote invasion and motility of NSCLC cells. Activation of Rac1 and regulation of some EMT/invasion-related genes may be involved in the underlying processes.

• Nutrition Research and Practice
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• 제15권5호
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• pp.579-590
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• 2021

BACKGROUND/OBJECTIVES: Petasites japonicus Maxim (P. japonicus) has been used as an edible and medicinal plant and contains many bioactive compounds. The purpose of this study is to investigate the effect of P. japonicus on osteogenesis. MATERIALS/METHODS: The leaves and stems of P. japonicus were separated and extracted with hot water or ethanol, respectively. The total phenolic compound and total polyphenol contents of each extract were measured, and alkaline phosphatase (ALP) activity of each extract was evaluated to determine their effect on bone metabolism. To investigate the effect on osteoblast differentiation of the aqueous extract of P. japonicus leaves (AL), which produced the highest ALP activity among the tested extracts, collagen content was measured using the Sirius Red staining method, mineralization using the Alizarin Red S staining method, and osteocalcin production through enzyme-linked immunosorbent assay analysis. Also, real-time reverse transcription polymerase chain reaction was performed to investigate the mRNA expression levels of Runt-related transcriptional factor 2 (Runx2) and Osterix. RESULTS: Among the 4 P. japonicus extracts, AL had the highest values in all of the following measures: total phenolic compounds, total polyphenols, and ALP activity, which is a major biomarker of osteoblast differentiation. The AL-treated MC3T3-E1 cells showed significant increases in induced osteoblast differentiation, collagen synthesis, mineralization, and osteocalcin production. In addition, mRNA expressions of Runx2 and Osterix, transcription factors that regulate osteoblast differentiation, were significantly increased. CONCLUSIONS: These results suggest that AL can regulate osteoblasts differentiation, at least in part through Runx2 and Osterix. Therefore, it is highly likely that P. japonicus will be useful as an alternate therapeutic for the prevention and treatment of osteoporosis.

• International Journal of Oral Biology
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• 제32권1호
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• pp.1-5
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• 2007

Receptor activator of nuclear factor ${\kappa}B$ ligand (RANKL) induces osteoclast formation from hematopoietic cells via up-regulation of positive regulators, including $NF-{\kappa}B$, c-Fos, microphthalmia transcription factor (Mitf), PU.1, and nuclear factor of activated T cells (NFAT) c1. In addition to the positive regulation by these transcription factors, RANKL appears to regulate negative regulators such as MafB and inhibitors of differentiation (Ids). Ids and MafB are abundantly expressed in osteoclast precursors, bone marrowderived monocyte/macrophage lineage cells (BMMs). Expression levels of these genes are significantly reduced by RANKL during osteoclastogenesis. Overexpression of these genes in BMMs inhibits the formation of tartarate-resistant acid phosphatase (TRAP)-positive multinuclear osteoclasts by down-regulation of NFATc1 and osteoclast-associated receptor (OSCAR), which are important for osteoclast differentiation. Furthermore, reduced expression of these genes enhances osteoclastogenesis and increases expression of NFATc1 and OSCAR. Taken together, RANKL induces osteoclastogenesis via up-regulation of positive regulators as well as down-regulation of negative regulators.

• 약학회지
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• 제50권3호
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• pp.184-190
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• 2006

We investigated the effect of fresh Rehmanniae radix methanol extracts (RGMeOH) on the in vitro production of cytokines by splenocytes and peritoneal macrophages isolated from C57BL/6 mice. Peritoneal macrophages and splenocytes were incubated with various concentrations of RGMeOH in the presence of $10\;{\mu}g/ml$ of lipopolysaccharide (LPS) $1\;{\mu}g/ml$ of concanavalin A (Con A) for cytokine assay, These results showed that RGMeOH remarkably attenuated LPS-increased production of $TNF-{\alpha}$ but not IL-6 by peritoneal macrophages and enhanced LPS-stimulated production of IL-10 in a dose-dependent manner RGMeOH significantly augmented the LPS- or Con A-stimulated production of IL-2 and $IFN-{\gamma}$ by splenocytes. These findings suggest that RGMeOH may attenuate inflammatory responses through down-regulation of $TNF-{\alpha}$ and up-regulation of IL-10, and that RGMeOH may up-regulate cell-mediated immune responses through increase in IL-2 and $IFN-{\gamma}$ production.

• 전력전자학회논문지
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• 제13권2호
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• pp.79-87
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• 2008

연료전지의 낮고 변동폭이 큰 전압을 안정된 높은 전압으로 승압시키기 위하여 부스트 컨버터가 사용되고 있다. 전기적인 절연이 요구되지 않는 응용에서는 손실, 가격 및 부피 상승의 원인이 되는 고주파 변압기가 없는 무변압기형의 부스트 컨버터가 장점을 갖는다. 본 논문에서는 새로운 무변압기형 부스트 컨버터를 제안한다. 제안한 컨버터는 $6{\sim}8$배의 실제 사용가능 한 승압비를 가지며 입 출력 전류 리플이 매우 작아 연료전지 응용에 적합하다. 이에 대한 이론적 해석과 시뮬레이션 및 실험파형을 통해 타당성을 검증하였다.

• Journal of Plant Biotechnology
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• 제37권3호
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• pp.327-336
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• 2010

Cysteine proteases have been known as a critical factor in plant defense mechanisms in pineapple, papaya, or wild fig. Papain or ficin is one kind of cysteine proteases that shows toxic effects to herbivorous insects and pathogenic bacteria. However, resistance to bacterial soft rot of plants genetically engineered with cysteine protease has been little examined thus far. We cloned a cysteine protease cDNA from Ananas comosus and introduced the gene into Chinese cabbage (Brassica rapa) under the control of the cauliflower mosaic virus 35S promoter. The transgene was stably integrated and actively transcribed in transgenic plants. In comparisons with wild-type plants, the $T_2$ and $T_3$ transgenic plants exhibited a significant increase in endo-protease activity in leaves and enhanced resistance to bacterial soft rot. A cDNA microarray analysis revealed that several genes were more abundantly transcribed in the transgenic than in the wild type. These genes encode a glyoxal oxidase, PR-1 protein, PDF1, protein kinase, LTP protein, UBA protein and protease inhibitor. These results suggest an important role for cysteine protease as a signaling regulator in biotic stress signaling pathways, leading to the build-up of defense mechanism to pathogenic bacteria in plants.

• Journal of Microbiology and Biotechnology
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• 제25권11호
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• pp.1787-1795
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• 2015

The transition from primary to secondary metabolism in antibiotic-producing Streptomyces correlates with expression of genes involved in stress responses. Consequently, regulatory pathways that regulate specific stress responses are potential targets to manipulate to increase antibiotic titers. In this study, genes encoding key proteins involved in regulation of the osmotic stress response in Streptomyces avermitilis, the industrial producer of avermectins, are investigated as targets. Disruption of either osaB_Sa, encoding a response regulator protein, or osaC_Sa, encoding a multidomain regulator of the alternative sigma factor SigB, led to increased production of both oligomycin, by up to 200%, and avermectin, by up to 37%. The mutations also conditionally affected morphological development; under osmotic stress, the mutants were unable to erect an aerial mycelium. In addition, we demonstrate the delivery of DNA into a streptomycete using biolistics. The data reveal that information on stress regulatory responses can be integrated in rational strain improvement to improve yields of bioactive secondary metabolites.

• Asian Pacific Journal of Cancer Prevention
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• 제14권2호
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• pp.885-889
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• 2013

microRNAs (miRNAs) are small non-coding RNAs that regulate gene expression through post-transcriptional interactions with mRNA. miRNAs have recently emerged as key regulators of various cancers. Although miR-27a has been implicated in several other cancers, its role in hepatitis B virus-related hepatocellular carcinoma (HCC) is unknown. In this study, we showed miR-27a to be frequently up-regulated in HCC tissues and HCC cell lines (HepG2 and Huh7). Overexpression of miR-27a enhanced cell proliferation, promoted migration and invasion, and activated cell cycling in HepG2 and Huh7 cells. In summary, our results suggest that up-regulation of miR-27a may play an oncogenic role in the development of HCC and might thus be a new therapeutic target in HCC patients.

• ALGAE
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• 제25권1호
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• pp.37-44
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• 2010

A tide-simulating apparatus was developed for culturing marine macroalgae. The objective of this study was to introduce a novel tide-simulating apparatus that can simulate a diurnal or semi-diurnal tidal cycle in the laboratory. In this apparatus, the seaweeds are move up and down and the water level remains the same during the simulated tidal cycle. The apparatus consists of 18 cylindrical culture tanks (3 blocks $\times$ 6 culture tanks) with 12 cm diameter and 24.5 cm long containing up to 2.5 L of seawater. There is a horizontal plate which covered all 18 culture tanks, and it is raised and lowered by a programmable motor that can regulate exposure time. In one application, seaweeds are attached to braided twine hung on Plexiglas air-tubing. The air-tubing is attached to a lid that is set on a horizontal plate. This apparatus is made of colorless Plexiglas to maximize light transmittance. This apparatus is easily disassembled and transportable to any indoor laboratory, wet laboratory, greenhouse, etc. This apparatus also offers considerable flexibility in terms of design. The size of culture tank can be redesigned by either increasing the height of cylinder or/and using a different diameter of cylindrical Plexiglas, therefore, larger/taller thalli can be cultivated. Growth rates of three eulittoral Porphyra species from different tidal elevations have been compared using this device.

• The Korean Journal of Physiology and Pharmacology
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• 제15권2호
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• pp.95-100
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• 2011

DREAM (downstream regulatory element antagonistic modulator) is a calcium-binding protein that regulates dynorphin expression, promotes potassium channel surface expression, and enhances presenilin processing in an expression level-dependent manner. However, no molecular mechanism has yet explained how protein levels of DREAM are regulated. Here we identified group I mGluR (mGluR1/5) as a positive regulator of DREAM protein expression. Overexpression of mGluR1/5 increased the cellular level of DREAM. Up-regulation of DREAM resulted in increased DREAM protein in both the nucleus and cytoplasm, where the protein acts as a transcriptional repressor and a modulator of its interacting proteins, respectively. DHPG (3,5-dihydroxyphenylglycine), a group I mGluR agonist, also up-regulated DREAM expression in cortical neurons. These results suggest that group I mGluR is the first identified receptor that may regulate DREAM activity in neurons.