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Pseudomonas aeruginosa Exotoxin A Induces Apoptosis in Chemoresistant YD-9 Human Oral Squamous Carcinoma Cell Line Via Accumulation of p53 and Activation of Caspases (항암제에 저항성을 가지는 YD-9 human oral squamous carcinoma cell line에서 Pseudomonas aeruginosa exotoxin A의 p53 단백질 누적과 caspase를 활성화 경로를 통해 유도된 세포자멸사)

  • Kim, Gyoo-Cheon;Gil, Young-Gi
    • Journal of Life Science
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    • v.19 no.8
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    • pp.1047-1054
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    • 2009
  • Oral squamous carcinoma (OSC) cells present resistance to chemotherapeutic agents-mediated apoptosis in the late stages of malignancy. Advances in the understanding of bacterial toxins have produced new strategies for the treatment of cancers. It was demonstrated here that Pseudomonas aeruginosa exotoxin A (PEA) significantly decreased the viability of chemoresistant YD-9 cells in the apoptosis mechanism. Apoptotic manifestations were evident through changes in nuclear morphology and generation of DNA fragmentation. PEA treatment induced caspase-3, -6 and -9 cleavage, and activation. These events preceded proteolysis of the caspase substrates poly (ADP-ribose) polymerase (PARP), DNA fragmentation factor 45 (DFF45), and lamin A in YD-9 cells. The reduction of mitochondrial membrane potential, release of cytochrome c and SmacjDlABLO from mitochondria to cytosol, andtranslocation of AlF into nucleus were shown. While p53, p21 and $14-3-3{\gamma}$ were upregulated, cyclin Band cdc2 were downregulated by PEA treatment. Taken together, PEA induces apoptosis in chemoresistant YD-9 cells via activation of caspases, mitochondrial events and regulation of cell cycle genes.

Induction of Apoptosis by HDAC Inhibitor Trichostatin A through Activation of Caspases and NF-κB in Human Prostate Epithelial Cells. (인체 전립선 상피세포에서 HDAC 저해제 trichostatin A의 caspase 및 NF-κB의 활성화를 통한 apoptosis 유도)

  • Park, Cheol;Jin, Cheng-Yun;Choi, Byung-Tae;Lee, Won-Ho;Choi, Yung-Hyun
    • Journal of Life Science
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    • v.18 no.3
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    • pp.336-343
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    • 2008
  • Histone deacetylases (HDACs) inhibitors have emerged as the accessory therapeutic agents for various human cancers, since they can block the activity of specific HDACs, restore the expression of some tumor suppressor genes and induce cell differentiation, cell cycle arrest and apoptosis in vitro and in vivo. In the present study, we investigated that the effect of trichostatin A (TSA), an HDAC inhibitor, on the cell growth and apoptosis, and its effect on the nuclear factor-kappaB $(NF-{\kappa}B)$ activity in 267B1 human prostate epithelial cells. Exposure of 267B1 cells to TSA resulted in growth inhibition and apoptosis induction in and dose-dependent manners as measured by fluorescence microscopy, agarose gel electrophoresis and flow cytometry analysis. TSA treatment inhibited the levels of IAP family members such as c-IAP-1 and c-IAP-2 and induced the proteolytic activation of caspase-3, -8 and -9, which were associated with concomitant degradation of poly (ADP-ribose)-polymerase, ${\beta}-catenin$ and laminin B proteins. The increase in apoptosis by TSA was connected with the translocation of $NF-{\kappa}B$ from cytosol to nucleus, increase of the DNA binding as well as promoter activity of $NF-{\kappa}B$, and degradation of cytosolic inhibitor of KappaB $(I{\kappa}B)-{\alpha}$ protein. We therefore concluded that TSA demonstrated anti-proliferative and apoptosis-inducing effects on 267B1 cells in vitro, and that the activation of caspases and $NF-{\kappa}B$ may play important roles in its mechanism of action. Although further studies are needed, these findings provided important insights into the possible molecular mechanisms of the anti-cancer activity of TSA.

Induction of G1 Phase Cell Cycle Arrest and Apoptotic Cell Death by 5-Fluorouracil in Ewing′s Sarcoma CHP-100 Cells (CHP-100 Ewing′s 육종세포에서 5-fluorouracil에 의한 G1 arrest 유도 및 apoptosis 유발에 관한 연구)

  • Kim, Sung Ok;Choi, Yung Hyun
    • Journal of Life Science
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    • v.26 no.9
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    • pp.1015-1021
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    • 2016
  • 5-fluorouracil (5-FU), a pyrimidine analog, is a widely used anticancer drug, which works through irreversible inhibition of thymidylate synthase. In the present study, it was investigated the anti-proliferative effects and molecular mechanisms of 5-FU using Ewing's Sarcoma CHP-100 Cells. The present data indicated that treatment of 5-FU to CHP-100 cells induced a G1 phase arrest of the cell cycle in a time-dependent manner. 5-FU-induced G1 arrest was correlated with the accumulation of the hypophosphorylated form of the retinoblastoma protein (pRB) and association of pRB with the transcription factors E2F-1 and E2F-4. Although 5-FU treatment did affect the levels of cyclin-dependent kinases, the levels of cyclin A and B were markedly down-regulated as compared with the untreated control group. In addition, 5-FU-induced G1 arrest of CHP-100 cells was also associated with the induction of apoptosis, as determined by apoptotic cell morphologies, degradation of poly(ADP-ribose) polymerase and Annexin V staining. Furthermore, 5-FU induced the loss of mitochondrial membrane potential with up-regulated pro-apoptotic Bax expression, down-regulated anti-apoptotic Bcl-2 expression and cytochrome c release from mitochondria to cytosol. Collectively, the data suggest that 5-FU is effective in inducing cell growth reduction and apoptosis, in part, by reducing phosphorylation of pRB and activating mitochondrial dysfunction in CHP-100 cells.

Anti-inflammatory Activities of Methanolic Extracts from Different Rose Cultivars (품종별 장미꽃 메탄올 추출물의 항염증 효과)

  • Lee, Seon-Mi;Li, Lin;Sung, Jeehye;Yang, Jinwoo;Kim, Younghwa;Jeong, Heon Sang;Lee, Junsoo
    • The Korean Journal of Food And Nutrition
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    • v.28 no.4
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    • pp.551-557
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    • 2015
  • The genus Rosa (Rosaceae) is an abundant source of phenolics and is traditionally used as a food supplement and as herbal medicine. Various plant phenolics are known to have anticancer, antioxidant, and anti-inflammatory properties. In this study, we investigated the anti-inflammatory effects of rose methanolic extracts (RMEs) from four different rose cultivars (Macarena, Onnuri, Oklahoma, and Colorado) in lipopolysaccharide (LPS)-activated RAW 264.7 cells. Our results demonstrated that pretreatment of REMs ($500{\mu}g/mL$) significantly reduced NO production by suppressing iNOS protein expression in LPS-stimulated cells. Anti-inflammatory effects by RMEs were observed in the following order: Oklahoma > Colorado > Onnuri > Macarena. Consistent with this finding, RMEs inhibited the translocation of $NF-{\kappa}B$ from the cytosol to the nucleus via the suppression of $I{\kappa}B{\alpha}$ phosphorylation and also inhibited LPS-stimulated $NF-{\kappa}B$ transcriptional activity. These findings suggest that RMEs exert anti-inflammatory actions and help to elucidate the mechanisms underlying the potential therapeutic values of RMEs. Therefore, RMEs could be regarded as a potential source of natural anti-inflammatory agents.

Effect of Plant Extracts on the Activity of Alcohol Dehydrogenase and the Antioxidation in Alcohol-treated Rat Hepatocyte (알코올 투여한 흰쥐 간세포내 알코올 탈수소효소의 활성과 항산화에 미치는 식물추출물들의 영향)

  • 조성환;김지철;김성완
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.30 no.4
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    • pp.679-683
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    • 2001
  • This study was purposed to compare the activity of alcohol dehydrogenase and antioxidative effects of several plant extracts in the alcohol-treated rat liver. Sprague-Dawley rat weighing about 200 g were divided into the following 6 groups : normal, alcohol group and 4 different plant extracts administrated groups(Soybean sprout, Pine needle, Lentinus edodes, acanthopanacis cortex). Each plant extract was administrated orally by 200mg/kg b.w./day for 8 days before the alcohol treatment (5 g of 30% alcohol /kg b.w. by i.p.injection). All rats were sacrificed at 90 min after the alcohol treatment. The alcohol concentrations in serum of Soybean sprout and pine needle group were significantly lower than the Lentinus edodes and Acanthopanacis cortex group. The activity of alcohol dehydrogenase in the hepatic cytosol of Soybean sprout and Pine needle group was also significantly higher than the alcohol and the other groups However, the activity of catalase seemed not to be affected, although the extract groups showed slightly higher activities of catalase than the alcohol group. These results may indicate that the extracts of Soybean sprout and Pine needle were relatvely effective on the alcohol degradation. the activity of blutathione-peroxidase and lipid peroxidaton of all of the extract groups were significantly lower than the activity of alcohol group. These results can suggest that all of the use plant extracts more or less have an antioxidative effect on the alcohol-induced oxidation and especially, extracts of Soybean sprout and Pine needle have an stimulating effect on the alcohol absorption and degradation.

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The Effects of Anti-Inflammatory Activities and Active Fractions Analysis of Ethanol Extract from Red Rose Petals (붉은 장미꽃잎 에탄올 추출물의 활성 분획물 분석 및 항염증 활성 효과)

  • Kim, Hyun Kyoung
    • The Journal of the Convergence on Culture Technology
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    • v.6 no.2
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    • pp.543-551
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    • 2020
  • Red rose petals are usually disposed but they are an abundant source of phenolics and traditionally used as food supplement and as herbal medicine. Of the Various phenolics, they are known to have anticancer, antioxidant, and anti-inflammatory properties. In this study, we investigated the anti-inflammatory effects of red rose ethanolic extracts(GRP) on lipopolysaccharide (LPS)-activated RAW 264.7 cells. The results demonstrated that pretreatment of GRP(500㎍/mL) significantly reduced NO production by suppressing iNOS protein expression in LPS-stimulated cells. Anti-inflammatory effects byred rose petal were observed in the following. Red rose petal inhibited the translocation of NF-κB from the cytosol to the nucleus via the suppression of IκB-α phosphorylation and also inhibited LPS-stimulated NF-κB transcriptional activity. These findings suggest that red rose petal exert anti-inflammatory actions and help to elucidate the mechanisms underlying the potential therapeutic values of red rose petal. Therefore, red rose petal could be regarded as a potential source of natural anti-inflammatory agents.

Dietary Aloe Reduces Adipogenesis via the Activation of AMPK and Suppresses Obesity-related Inflammation in Obese Mice

  • Shin, Eun-Ju;Shin, Seul-Mee;Kong, Hyun-Seok;Lee, Sung-Won;Do, Seon-Gil;Jo, Tae-Hyung;Park, Young-In;Lee, Chong-Kil;Hwang, In-Kyeong;Kim, Kyung-Jae
    • IMMUNE NETWORK
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    • v.11 no.2
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    • pp.107-113
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    • 2011
  • Background: Metabolic disorders, including type II diabetes and obesity, present major health risks in industrialized countries. AMP-activated protein kinase (AMPK) has become the focus of a great deal of attention as a novel therapeutic target for the treatment of metabolic syndromes. In this study, we evaluated whether dietary aloe could reduce obesity-induced inflammation and adipogenesis. Methods: Male C57BL/6 obese mice fed a high-fat diet for 54 days received a supplement of aloe formula (PAG, ALS, Aloe QDM, and Aloe QDM complex) or pioglitazone (PGZ) and were compared with unsupplemented controls (high-fat diet; HFD) or mice fed a regular diet (RD). RT-PCR and western blot analysis were used to quantify the expression of obesity-induced inflammation. Results: Aloe QDM complex downregulated fat size through suppressed expression of scavenger receptors on adipose tissue macrophages (ATMs) compared with HFD. Both white adipose tissue (WATs) and muscle exhibited increased AMPK activation through aloe supplementation, and in particular, the Aloe QDM complex. Obesity-induced inflammatory cytokines (IL-$1{\beta}$ and -6) and $HIF1{\alpha}$ mRNA and protein were decreased markedly, as was macrophage infiltration by the Aloe QDM complex. Further, the Aloe QDM complex decreased the translocation of NF-${\kappa}B$ p65 from the cytosol in the WAT. Conclusion: Dietary aloe formula reduced obesity-induced inflammatory responses by activation of AMPK in muscle and suppression of proinflammatory cytokines in the WAT. Additionally, the expression of scavenger receptors in the ATM and activation of AMPK in WAT led to reduction in the percent of body fat. Thus, we suggest that the effect of the Aloe QDM complex in the WAT and muscle are related to activation of AMPK and its use as a nutritional intervention against T2D and obesity-related inflammation.

Mechanism underlying NO-induced apoptosis in human gingival fibroblasts

  • Hwang, In-Nam;Jeong, Yeon-Jin;Jung, Ji-Yeon;Lee, Jin-Ha;Kim, Kang-Moon;Kim, Won-Jae
    • International Journal of Oral Biology
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    • v.34 no.1
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    • pp.7-14
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    • 2009
  • Nitric oxide (NO) acts as an intracellular messenger at the physiological level but can be cytotoxic at high concentrations. The cells within periodontal tissues, such as gingival and periodontal fibroblasts, contain nitric oxide syntheses and produce high concentrations of NO when exposed to bacterial lipopolysaccharides and cytokines. However, the cellular mechanisms underlying NO-induced cytotoxicity in periodontal tissues are unclear at present. In our current study, we examined the NO-induced cytotoxic mechanisms in human gingival fibroblasts (HGF). Cell viability and the levels of reactive oxygen species (ROS) were determined using a MTT assay and a fluorescent spectrometer, respectively. The morphological changes in the cells were examined by Diff-Quick staining. Expression of the Bcl-2 family and Fas was determined by RT-PCR or western blotting. The activity of caspase-3, -8 and -9 was assessed using a spectrophotometer. Sodium nitroprusside (SNP), a NO donor, decreased the cell viability of the HGF cells in a dose- and time-dependent manner. SNP enhanced the production of ROS, which was ameliorated by NAC, a free radical scavenger. ODQ, a soluble guanylate cyclase inhibitor, did not block the SNP-induced decrease in cell viability. SNP also caused apoptotic morphological changes, including cell shrinkage, chromatin condensation, and DNA fragmentation. The expression of Bax, a member of the proapoptotic Bcl-2 family, was upregulated in the SNP-treated HGF cells, whereas the expression of Bcl-2, a member of the anti-apoptotic Bcl-2 family, was downregulated. SNP augmented the release of cytochrome c from the mitochondria into the cytosol and enhanced the activity of caspase-8, -9, and -3. SNP also upregulated Fas, a component of the death receptor assembly. These results suggest that NO induces apoptosis in human gingival fibroblast via ROS and the Bcl-2 family through both mitochondrial- and death receptor-mediated pathways. Our data also indicate that the cyclic GMP pathway is not involved in NO-induced apoptosis.

Anti-Inflammatory Effects of 1,2,3,4,6-Penta-O-Galloyl-β-D-Glucose in LPS-Stimulated Macrophages (LPS로 자극한 대식세포에서 1,2,3,4,6-Penta-O-Galloyl-β-D-Glucose의 염증 억제 효과)

  • Lee, Hee Won;Kang, Ye Rim;Bae, Min Seo;Kim, Yoon Hee
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.46 no.4
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    • pp.409-416
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    • 2017
  • 1,2,3,4,6-Penta-O-galloyl-${\beta}$-D-glucose (PGG) is a gallotannin isolated from Galla Rhois. In a previous study, PGG was shown to suppress the allergic response by attenuating immunoglobulin E production both in vitro and in vivo. However, the effect of PGG on bacteria-induced inflammation at physiological concentration remains unclear. Therefore, the aim of this study was to investigate the effect of PGG on lipopolysaccharide (LPS)-stimulated macrophages. PGG inhibited release of nitric oxide (NO) and prostaglandin $E_2$ by alleviating protein expression of inducible NO synthase and cyclooxygenase-2 in LPS-treated RAW264.7 cells. Furthermore, PGG suppressed the release of interleukin-6 and tumor necrosis factor-${\alpha}$ induced by LPS. Further study indicated that PGG blocked translocation of the p65 subunit of nuclear factor-${\kappa}B$ from the cytosol into the nucleus, which is one of the underlying mechanisms of the anti-inflammatory action of PGG. Collectively, these data suggest that PGG might be useful for the treatment of inflammatory disease.

Characterization of Sporulation-Specific Glucoamylase of Saccharomyces diastaticus (Saccharomyces diastaticus의 포자형성 특이 글루코아밀라제의 특성)

  • Kim, Eun-Ju;Ahn, Jong-Seog;Kang, Dae-Ook
    • Journal of Life Science
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    • v.20 no.5
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    • pp.683-690
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    • 2010
  • The yeast strains of Saccharomyces diastaticus produce one of three isozymes of an extracellular glucoamylase I, II or III, a type of exo-enzyme which can hydrolyse starch to generate glucose molecules from non-reducing ends. These enzymes are encoded by the STA1, STA2 and STA3 genes. Another gene, sporulation-specific glucoamylase (SGA), also exists in the genus Saccharomyces which is very homologous to the STA genes. The SGA has been known to be produced in the cytosol during sporulation. However, we hypothesized that the SGA is capable of being secreted to the extracellular region because of about 20 hydrophobic amino acid residues at the N-terminus which can function as a signal peptide. We expressed the cloned SGA gene in S. diastaticus YIY345. In order to compare the biochemical properties of the extracellular glucoamylase and the SGA, the SGA was purified from the culture supernatant through ammonium sulfate precipitation, DEAE-Sephadex A-50, CM-Sephadex C-50 and Sephadex G-200 chromatography. The molecular weight of the intact SGA was estimated to be about 130 kDa by gel filtration chromatography with high performance liquid chromatography (HPLC) column. Sodium dedecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis showed it was composed of two heterogeneous subunits, 63 kDa and 68 kDa. The deglycosylation of the SGA generated a new 59 kDa band on the SDS-PAGE analysis, indicating that two subunits are glycosylated but the extent of glycosylation is different between them. The optimum pH and temperature of the SGA were 5.5 and $45^{\circ}C$, respectively, whereas those for the extracellular glucoamylase were 5.0 and $50^{\circ}C$. The SGA were more sensitive to heat and SDS than the extracellular glucoamylase.