• Korean Journal of Microbiology
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• v.42 no.4
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• pp.319-325
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• 2006

[ $\beta$ ]-Glucans (AG) were prepared from Agaricus blazei cultured in the medium fortified with the roots of Pueraria spp. by repeated extraction with hot water, gel filtration chromatography and DEAE ion exchange chromatography. Oligosaccharides (AO) were derived from the hydrolysis of AG by an endo-$\beta$-(1$\rightarrow$6)-glucanase from Bacillus megaterium. The anti-HT-29 human colon cancer activity of AG or AO was investigated using MTT assay, apoptosis assay, cell cycle analysis, and cDNA microairay. AG and AO both inhibited proliferation and growth of HT-29 cells, and stimulated apoptosis of the cells in a dose-dependent manner. In cell cycle analysis, treating HT-29 cells with AG or AO resulted in the increase of cells in the G0 (sub-G1) and G1 phase. Especially, AO was more effective in inducing G0/G1 cell cycle arrest than AG. To screen the genes involved in the increase of apoptosis, the gene expression profile of the HT-29 cells treated with AO was examined by cDNA microarray. While several genes involved in cell cycle progression (CCND2 and CDK2) were down-regulated, many genes involved in apoptosis (TNFSF9, TNFRSF9, FADD, CASP8, BAD, CRADD, CASP9 etc), cell cycle inhibitor (CDKN2A), immune response (IL6, IL18, IL6R etc), and tumor suppressor (CEACAM1, TP53BP2, IRF1, and PHB) were up-regulated. These results suggest that AO could inhibit the proliferation and growth of HT-29 cells by G0/G1 cell cycle arrest and induction of apoptosis.

• Journal of Oral Medicine and Pain
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• v.34 no.3
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• pp.261-276
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• 2009

Lactacystin, a microbial natural product synthesized by Streptomyces, has been commonly used as a selective proteasome inhibitor in many studies. Proteasome inhibitors is known to be preventing the proliferation of cancer cells in vivo as well as in vitro. Furthermore, proteasome inhibitors, as single or combined with other anticancer agents, are suggested as a new class of potential anticancer agents. This study was undertaken to examine in vitro effects of cytotoxicity and growth inhibition, and the molecular mechanism underlying induction of apoptosis in SCC25 human tongue sqaumous cell carcinoma cell line treated with lactacystin. The viability of SCC25 cells, human normal keratinocytes (HaCaT cells) and human gingiva fibroblasts (HGF-1 cells), and the growth inhibition of SCC25 cells were assessed by MTT assay and clonogenic assay respectively. The hoechst staining, hemacolor staining and TUNEL staining were conducted to observe SCC25 cells undergoing apoptosis. SCC25 cells were treated with lactacystin, and Western blotting, immunocytochemistry, confocal microscopy, FAScan flow cytometry, MMP activity, and proteasome activity were performed. Lactacystin treatment of SCC25 cells resulted in a time- and does-dependent decrease of cell viability and a does-dependent inhibition of cell growth, and induced apoptotic cell death. Interestingly, lactacytin remarkably revealed cytotoxicity in SCC25 cells but not normal cells. And tested SCC25 cells showed several lines of apoptotic manifestation such as nuclear condensation, DNA fragmentation, the reduction of MMP and proteasome activity, the decrease of DNA contents, the release of cytochrome c into cytosol, the translocation of AIF and DFF40 (CAD) onto nuclei, the up-regulation of Bax, and the activation of caspase-7, caspase-3, PARP, lamin A/C and DFF45 (ICAD). Flow cytometric analysis revealed that lactacystin resulted in G1 arrest in cell cycle progression which was associated with up-regulation in the protein expression of CDK inhibitors, $p21^{WAF1/CIP1}$ and $p27^{KIP1}$. We presented data indicating that lactacystin induces G1 cell cycle arrest and apoptois via proteasome, mitochondria and caspase pathway in SCC25 cells. Therefore our data provide the possibility that lactacystin could be as a novel therapeutic strategy for human tongue squamous cell carcinoma.

• Journal of Life Science
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• v.21 no.9
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• pp.1346-1353
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• 2011

Sophora tonkinensis Gapnep has been used as a traditional herbal medicine in oriental regions since ancient times. In this study, the effect and mechanism of the MeOH extract of Sophora tonkinensis Gapnep (STME) on adipocite differentiation and adipogenesis in 3T3-L1 preadipocites were investigated. Treatment with STME in the concentration range of 0-200 ${\mu}g$/ml significantly inhibited the differentiation of 3T3-L1 preadipocites in a dose-dependent manner, as determined by a decrease in intracellular lipid droplets and lipid contents measured by Oil Red O staining. In association with the inhibitory effect of lipid accumulation, the expressions of the proteins concerned with adipogenesis in 3T3-L1 preadipocites were also investigated. Treatment with STME reduced the expressions of peroxisome proliferator-activated receptor ${\gamma}$ (PPAR${\gamma}$), cytidine-cytidine-adenosine-adenosine-thymine (CCAAT)/enhancer-binding proteins ${\alpha}$ and ${\beta}$ (C/EBP${\alpha}$ and C/EBP${\beta}$) and sterol regulatory element binding protein (SREBP), which are adipocyte specific markers. In flow cytometry analysis, the inhibitory effect of differentiation was caused by G1 arrest and following mitotic clonal expansion cease. Therefore, we also investigated the alteration of G1 phase arrest-related proteins. As a result, the expression of p21 protein was significantly increased, while the expressions of Cdk2, E2F-1 and phospho-Rb were reduced in a dose-dependent manner in STME treated 3T3-L1 cells. According to these results, STME might inhibit differentiation through G1 arrest in 3T3-L1 preadipocytes adipogenesis, and further studies, which are in progress, have to be completed to identify the active compounds.

• The Journal of Korean Academy of Prosthodontics
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• v.59 no.4
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• pp.379-394
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• 2021

Purpose. In our previous studies, application of trichloroacetic acid (TCA) to gingival fibroblasts or to canine palatal soft tissue was verified to alter the expression of several genes responsible for cell cycle progression. In order to confirm this effect in a system allowing sequential release of TCA and epidermal growth factor (EGF), expression of various cell cycle genes following the application of the agents, using hydrophobically modified glycol chitosan (HGC)-based nano-controlled release system, was explored in this study. Materials and methods. HGC-based nano-controlled release system was developed followed by loading TCA and EGF. The groups were defined as the control (CON); TCA-loaded nano-controlled release system (EXP1); TCA- and EGF- individually loaded nano-controlled release system (EXP2). At 24- and 48 hr culture, expression of 37 cell cycle genes was analyzed in human gingival fibroblasts. Correlations and the influential genes were also analyzed. Results. Numerous genes such as cyclins (CCNDs), cell division cycles (CDCs), cyclin-dependent kinases (CDKs), E2F transcription factors (E2Fs), extracellular signal-regulated kinases (ERKs) and other cell cycle genes were significantly up-regulated in EXP1 and EXP2. Also, cell cycle arrest genes of E2F4, E2F5, and GADD45G were up-regulated but another cell cycle arrest gene SMAD4 was down-regulated. From the multiple regression analysis, CCNA2, CDK4, and ANAPC4 were determined as the most influential factors on the expression of ERK genes. Conclusion. Application of TCA and EGF, using the HGC-based nano-controlled sequential release system significantly up-regulated various cell cycle progression genes, leading to the possibility of regenerating oral soft tissue via application of the proposed system.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.5
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• pp.1025-1034
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• 2002

The herbal extract (YMT_02) is a modified herbal extracts from Yukmijihwang-tang (YMJ) to promote memory-enhancing. The YMJ extracts has been widely used as an anti-aging herbal medicine for hundred years in Asian countries. The purpose of this study is to; 1) quantitatively evaluate the memory-enhancing effect of YMT_02 by behavior task, 2) identify candidate genes responsible for enhancing memory by cDNA microarray and 3) assess the anti-oxidant effect of YMT_02 on PC12 cell. Memory retention abilities are addressed by passive avoidance task with Sprague-Dawley (SD) male rat. Before the training session, the rats are subdivided into four groups and administrated with YMT_02, Ginkgo biloba, Soya lecithin and normal saline for 10 days. The retention test was performed. 24 hours after the training session. The retention time of the YMT_02 group was significantly (p<0.05) delayed (～100%), whereas Ginkgo biloba and Soya lecithin treatment delayed 20% and 10% respectively. The hippocampi of YMT_02 and control group were dissected and mANA was further purified. After synthesizing cDNA using oligo-dT primer, the cDNA were applied to Incyte rat GEMTM 2 cDNA microarray. The microarray results show that prealbumin(transthyretin), phosphotidylethanolamine N-methyltransferase, and PEP-19 are expressed abundantly in the YMT_02 treated group. Especially, PEP-19 is a neuron-specific protein, which inhibits apoptotic processes in neuronal cell. On the other hand, transcripts of RAB15, glutamate receptor subunit 2 and CDK108 are abundant in control group. Besides, neuronal genes involved in neuronal death or neurodegeneration such as neuronal-pentraxin and spectrin are abundantly expressed in control group. Additionally, the YMT_02 shows an anti oxidative effect in the PC12 cell. The list of differentially expressed genes may implicate further insight on the action and mechanism behind the memory-enhancing effect of herbal extracts YMT_02, for example, anti-apoptotic, anti-oxidative, and neuroprotective effects.

• Journal of Life Science
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• v.28 no.7
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• pp.765-771
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• 2018

Peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$) is a key transcription factor that regulates adipogenesis, and epigenetic control of $PPAR{\gamma}$ is of great interest in obesity-inhibition research. Our previous study showed that CACUL1 (CDK2-associated cullin domain 1) acts as a corepressor that inhibits $PPAR{\gamma}$ transcriptional activity and adipocyte differentiation. Here, we investigated the roles of protein arginine methyltransferase 5 (PRMT5), a novel binding partner of CACUL1, in regulating $PPAR{\gamma}$. The interaction between PRMT5 and CACUL1 was shown by immunoprecipitation assay in vivo and GST pulldown assay in vitro. As shown by luciferase reporter assay, PRMT5 and CACUL1 cooperated to inhibit the transcriptional activity of $PPAR{\gamma}$. The suppressive role of PRMT5 in adipogenesis was examined by Oil Red O staining using 3T3-L1 cells, which stably overexpress or deplete PRMT5. Overexpression of PRMT5 suppresses $PPAR{\gamma}$-mediated adipogenesis, whereas PRMT5 knockdown increases lipid accumulation in 3T3-L1 cells. Consistently, PRMT5 attenuates the expression of Lpl and aP2, the target genes of $PPAR{\gamma}$, as demonstrated by RT-qPCR analysis. Overall, these results suggest that PRMT5 interacts with CACUL1 to impair the transcriptional activity of $PPAR{\gamma}$, leading to the inhibition of adipocyte differentiation. Therefore, the regulation of PRMT5 enzymatic activity may provide a clue to develop an anti-obesity drug.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.5
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• pp.1226-1232
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• 2007

Phellinus linteus is a well-known Oriental medicinal fungus that has various biological activities, including immunomodulatory and anti-tumor activities, the mechanisms of which are poorly understood. In the present study, we investigated the anti-proliferative activity of the methanol extract of P. linteus-Barley corn (MEPLB) in human lekemic U937 cells. It was found that exposure of U937 cells to MEPLB resulted morphological change and growth inhibition in a dose-dependent manner as measured by trypan blue count and MTT assay. Upon treatment with MEPLB, U937 cells developed many of the hallmark features of apoptosis, including condensation of chromatin and an increase in the sub-G1 population suggesting that the anti-proliferative effect of MEPLB is associated with the induction of apoptosis. The anti-proliferative and apoptotic effects of MEPLB were connected with a marked induction of the pro-apoptotic Bax and cyclin-dependent kinase (Cdk) inhibitor p21 in a p53-independent manner. Additionally, MEPLB treatment significantly induced the caspase-3 activity in U937 cells. Taken together, the present results suggest that apoptotic signals evoked by MEPLB in human leukemic U937 cells may converge caspase-3 activation through an up-regulation of Bax rather than a down-regulation of Bcl-2 or Bel-xL.

• Biomolecules & Therapeutics
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• v.24 no.4
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• pp.363-370
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• 2016

Cardiovascular disease is the most common cause of death in diabetic patients. Hyperglycemia is the primary characteristic of diabetes and is associated with many complications. The role of hyperglycemia in the dysfunction of human cardiac progenitor cells that can regenerate damaged cardiac tissue has been investigated, but the exact mechanism underlying this association is not clear. Thus, we examined whether hyperglycemia could regulate mitochondrial dynamics and lead to cardiac progenitor cell dysfunction, and whether blocking glucose uptake could rescue this dysfunction. High glucose in cardiac progenitor cells results in reduced cell viability and decreased expression of cell cycle-related molecules, including CDK2 and cyclin E. A tube formation assay revealed that hyperglycemia led to a significant decrease in the tube-forming ability of cardiac progenitor cells. Fluorescent labeling of cardiac progenitor cell mitochondria revealed that hyperglycemia alters mitochondrial dynamics and increases expression of fission-related proteins, including Fis1 and Drp1. Moreover, we showed that specific blockage of GLUT1 improved cell viability, tube formation, and regulation of mitochondrial dynamics in cardiac progenitor cells. To our knowledge, this study is the first to demonstrate that high glucose leads to cardiac progenitor cell dysfunction through an increase in mitochondrial fission, and that a GLUT1 blocker can rescue cardiac progenitor cell dysfunction and downregulation of mitochondrial fission. Combined therapy with cardiac progenitor cells and a GLUT1 blocker may provide a novel strategy for cardiac progenitor cell therapy in cardiovascular disease patients with diabetes.

• The Journal of Internal Korean Medicine
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• v.22 no.4
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• pp.579-587
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• 2001

The efficacy of Sagunja-tang and Sagunja-tang plus Mylabris phalerata against the human stomach cancer was examined and molecular biological fight of its actions was studied. In the efficacy test of anti-stomach cancer cells growth using the MTT assay, administration of Sagunja-tang resulted in no significant change of stomach cancer cells growth, with the control group. Administration of Sagunja-tang plus Mylabris phalerata resulted in a decrease of stomach cancer cells growth in proportion to the concentration of mylabris phalerata and time, which was significantly different from the control group(significance recognized when p<0.05). In the test using the apoptosis assay, administration of Sagunja-tang showed an increase in apoptosis of human stomach cancer cells, with no significant difference from the control group. Administrating Sagunja-tang plus Mylabris phalerata showed an increase in apoptosis of stomach cancer cells in proportion to the concentration of mylabris phalerata and time, which was significantly different from the control group(significance recognized when p<0.05). In the test using the quantitative RT-PCR to examine stomach cancer cells growth and revelation of apoptosis related genes, administrating Sagunja-tang plus Mylabris phalerata resulted in a decrease of Bcl-2, an anti-apoptosis gene, in proportiong to concentration. No significant change was examined in the revelation of CDK1, Cdc2, Cyclin D1, PCNA, c-myc, which are genes related to the stomach cancer cells growth, and Bax, Bel-XL, the genes related to apoptosis, and p53. Referring to the results above, Sagunja-tang plus Mylabris phalerata may be considered to have an anti-growth efficacy against human stomach cancer cells, and an inducement efficacy. Therefore, it can be clinically implemented in the human stomach cancer.

• Journal of Microbiology and Biotechnology
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• v.10 no.1
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• pp.27-34
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• 2000

The chloroform and methanol (2;1, v/v) extract from an edible plant, Actinidia arguta Planchon, appeared to possess antitumor activity against human leukemias Jurkat T and U937 cells through inducing apoptosis. The substance in the solvent extract was purified by silica gel column chromatography, preparative TLC, and Sephadex LH-20 column chromatography. Characteristics of the substance analyzed by UV scanning analysis, $^1H$ and $^{13}C$ NMR spectra suggested that the substance belongs to the chlorophyll derivatives-like group. The $IC_{50}$ value of the chlorophyll derivative (Cp-D) determined by MTT assay was $15\mu\textrm{g}/ml$ for Jurkat, $10\mu\textrm{g}/ml$ for U937, and $11.4\mu\textrm{g}/ml$ for HL-60m and was more toxic to these leukemias than to solid tumors or normal fibroblast. In order to elucidate cellular mechanisms underlying the cytotoxicity, the effect of the Cp-D on Jurkat T cells was investigated. When cells were treated with the Cp-D at a concentration of $15\mu\textrm{g}/ml$, [3H]thymidine incorporation declined rapidly and wa undetectable in 1h. However, no significant changes were made in the cell cycle distribution of the cells by 24h. The sub-Gl peak representing apoptotic cells began to be detectable in 36h, at which time apoptotic DNA fragmentation was also detected on agarose gel electrophoresis, demonstrating that the cytotoxic effect of the Cp-D is attributable to the induced apoptosis. Under the same conditions, although the protein level of cyclin-dependent kinases such as cdc4, csk6, cdk2, and cdc2 was not significantly changed until 24h, the kinase activity of all c안 rapidly declined and reached a minimum level within 1-6h and then recovered to the initial level by 12h and sustained until 24h. These results suggest that inactivation of cdks at an inappropriate time during the cell cycle progression in jurkat T cells following a treatment with the Cp-D leads to induction of apoptotic cell death.