• 동의생리병리학회지
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• 제19권1호
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• pp.124-129
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• 2005

Resveratrol, a phytoalexin found at high levels in grapes and in grape products such as red wine, has been reported to possess a wide range of biological and pharmacological activities including anti-oxident, anti-inflammatory, anti-mutagenic, and anti-carcinogenic effects, but its molecular mechanism is poorly understood. In this study, we examined the effects of resveratrol on lipopolysaccharide (LPS)-induced growth inhibitory activity and cell growth-regulatory gene products in astroglioma C6 cells to elucidate its possible mechanism for anti-cytotoxicity. It is shown that LPS induced time-dependent growth inhibition and morphological changes of C6 cells, which were recovered by pre-treatment with resveratrol. The anti-proliferative effect of LPS was associated with the induction of tumor suppressor p53 and cyclin-dependent kinase (Cdk) inhibitor p21 (WAF1/CIP1) expression assessed by RT-PCR and Western blot analysis in time-dependent manner in C6 cells. In addition, the pro-apoptotic Bax expression was also up-regulated in LPS-treated C6 cells without alteration of anti-apoptotic Bcl-2 and Bcl-XL expression. However, resveratrol significantly inhibited LPS-induced p53, p21 and Bax levels, suggesting that the modulation of p53, p21 and Bax levels could be one of the possible pathways by which resveratrol functions as anti-cytotoxic agent.

• Archives of Pharmacal Research
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• 제27권8호
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• pp.834-839
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• 2004

In human neuroblastoma SK-N-BE(2) cells undergoing apoptotic death induced by ginsenos-ide Rh2, a dammarane glycoside that was isolated from Panax ginseng C. A. Meyer, caspase-1 and caspase-3 were activated. The expression of Bax was increased in the cells treated with ginsenoside Rh2, whereas Bcl-2 expression was not altered. Treatment with caspase-1 inhibi-tor, Ac-YVAD-CMK, or caspase-3 inhibitor, Z-DEVD-FMK, partially inhibited ginsenoside Rh2-induced cell death but almost suppressed the cleavage of the 116 kDa PARP into a 85 kDa fragment. When the levels of p53 were examined in this process, p53 accumulated rapidly in the cells treated early with ginsenoside Rh2. These results suggest that activation of caspase-1 and -3 and the up-regulation of Bax are required in order for apoptotic death of SK-N-BE(2) cells to be induced by ginsenoside Rh2, and p53 plays an important role in the pathways to promote apoptosis.

• Radiation Oncology Journal
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• 제19권2호
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• pp.153-162
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• 2001

목적 : 방사선 조사에 의하여 유발되는 세포고사의 신호전달기전, 특히 caspase계 cysteine protease의 활성화, Bcl2 및 Bax 단백질, cytochrome c의 세포질내로의 방출, Fas 와 Fas-L 단백질의 발현양상 등의 조사를 통하여 방사선 조사에 의하여 유발되는 세포고사기전을 규명하고자 하였다. 대상 및 방법 : HL-60 세포주에 6 MV의 X-선을 조사하고 세포생존율, Caspase의 활성도, $Bcl_2$ 및 Bax 단백질, cytochrome c의 세포질내로의 방출여부, 및 Fas 와 Fas-L 단백질의 발현양상을 조사하였다. 결과 : 방사선조사 후 세포의 생존율은 조사선량과 조사 후 시간경과에 따라 감소되었다. 세포고사의 특징인 사다리형 DNA 분절은 방사선조사 4시간 후부터 시간경과에 따라 증가하였으며, 조사선량이 증가할수록 더욱 현저하였다. 방사선조사 후 caspase계 cysteine proteases 중 caspase-2, 3, 6, 8 및 9의 활성화가 시간경과에 따라 증가하였으며, 16 Gy의 방사선량조사 4시간 후에 poly (ADP-ribosyl) polymerase (PARP)의 분절과 Western blot을 이용한 procaspase-3의 분절을 확인함으로서 caspase-3의 활성을 간접적으로 증명할 수 있었다. $Bcl_2$ 단백질은 방사선조사 후 시간경과에 따라 감소하였으며, Bax 단백질은 시간경과에 따라 발현이 증가하는 양상을 관찰할 수 있었다. 방사선조사 후 cytochrome c의 세포질내로의 방출을 확인하였다. 또한 Fas 및 Fas-L 단백질 모두 방사선조사 후 발현이 증가하는 양상을 관찰할 수 있었다. 결론 : HL-60 세포주에서 방사선 조사에 의해 유발되는 세포사멸이 세포고사기전에 의해서 매개됨을 확인하였으며, 이는 세포내 caspase계 cysteine proteases, $Bcl_2$, Bax, 세포질내로의 cytochrome c 방출 그리고 Fas, Fas-L가 관여하는 신호전달경로의 활성화에 의한 것임을 의미하였다.

• 한국생명과학회:학술대회논문집
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• 한국생명과학회 2005년도 국제학술심포지움 The 44th Annual Meeting of Korean Society for Life Science
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• pp.23-36
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• 2005

Bax, a mammalian pro-apoptotic member of the Bcl-2 family, induces cell death when expressed In yeast. To investigate whether .Bax expression can induce cell death in plant, we produced transgenic Arabidopsis plants that contained murine Bax cDNA under control of a glucocorticoid-inducible promoter. Transgenic plants treated with dexamethasone, a strong synthetic glucocorticoid, induced Bax accumulation and cell death, suggesting that some elements of cell death mechanism by Bax may be conserved among various orgarusms. Therefore, we developed novel yeast genetic system, and cloned several Plant Bax Inhibitors (PBIs). Here, we report the function of two PBIs In detail. PBIl is ascorbate peroxidase (sAPX). Fluorescence method of dihydrorhodamine123 oxidation revealed that expression of Bax in yeast cells generated reactive oxygen species (ROS), and which was greatly reduced by co-expression with sAPX. These results suggest that sAPX inhibits the generation of ROS by Bax, which in turn suppresses Bax-induced cell death in yeast. PBI2 encodes nucleoside diphosphate kinase (NDPK). ROS stress strongly induces the expression of the NDPK2 gene in Arabidopsis thaliana (AtNDPK2). Transgenic plants overexpressing AtNDPK2 have lower lovels of ROS than wildtype plants. Mutants lacking AtNDPK2 had higher levels of ROS than wildtype. H$_{2O2}$ treatment induced the phosphorylation of two endogenous proteins whose molecular weights suggested they are AtMPK3 and AtMPK6. In the absence of H2O2 treatment, phosphorylation of these proteins was slightly elevated in plants overexpressing AtNDPK2 but markedly decreased In the AtNDPK2 deletion mutant. Yeast two-hybrid and in vitro protein pull-down assays revealed that AtNDPK2 specifically interacts with AtMPK3 and AtMPK6. Furthermore, AtNDPK2 also enhances the MBP phosphorylation activity of AtMPK3 i'n vitro. Finally, constitutive overexpression of AtNDPK2 in Arabidopsis plants conferred an enhanced tolerance to multiple environmental stresses that elicit ROS accumulation In situ. Thus, AtNDPK2 appears to play a novel regulatory role in H2O2-mediated MAPK signaling in plants.

• 대한한의학회지
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• 제20권1호
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• pp.91-105
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• 1999

The effects of Yinjin and Yinjinsaryongsangagambang on a DNA damaging agent, etoposide-induced apoptosis, cell viability, cell cycle progression, and mRNA expression of apoptosis-related genes of human hepatocyte cell line HepG2 were investigated using tryphan blue exclusion assay, MTT assay, flow cytometry, immunocytometric analysis of PCNA, and quantitative RT-PCR analysis. MTT assay showed that Yinjin and Yinjinsaryongsangagambang increases cellular viability of HepG2 cells in a dosage-dependent manner. Stimulation of cell cycle progression by Yinjin or Yinjinsaryongsangagambang was detected by flow cytometric analysis of the DNA content and immunocytometric analysis of PCNA expression. A significant reduction of a DNA-damaging agent, etoposide-induced apoptosis were found in both Yinjin and Yinjinsaryongsangagambang-treated cells in dosage-dependent manner. In overall, 3-fold reduction of apoptosis was recognized in $10.0\;{\mu}g/ml$ of Yinjin or Yinjinsaryongsangagambang-treated cells compared to untreated cells. Although the difference is not significant, Yinjinsaryongsangagambang showed slightly higher effect on the inhibition of apoptosis than Yinjin. From flow cytometric analysis of apoptosis, while 39.9% of untreated cells showed etoposide-induced apoptotic cell death, only 19.6% or 17.4% of Yinjin or Yinjinsaryongsangagambang-treated cells were fond at apoptotic sub G1 phase, respectively. Interestingly, strong induction of Gadd45-mRNA was observed from Yinjin or Yinjinsaryongsangagambang-treated cells. However, no changes in expression levels of p53 and Waf1 were detected, demonstrating that induction of Gadd45 mRNA expression by Yinjin or Yinjinsaryongsangagambang occurs by p53-independent mechanism. Marked mRNA inductions of two apoptosis-inhibiting genes, Bcl-2 and Bcl- XL, were found in both Yinjin or Yinjinsaryongsangagambang-treated HepG2 cells while no changes was detected in expression levels of an apoptosis-promoting gene, Bax.

• Journal of Ginseng Research
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• 제43권4호
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• pp.618-624
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• 2019

Background: Ginsenoside Re (Re) is one of the major components of Panax ginseng Meyer. Ginsenoside $Rk_3$ ($Rk_3$) is a secondary metabolite of Re. The aim of this study was to investigate and compare the effects and underlying mechanisms of Re and $Rk_3$ on cyclophosphamide-induced myelosuppression. Methods: The mice myelosuppression model was established by intraperitoneal (i.p.) injection of cyclophosphamide. Peripheral blood cells, bone marrow nucleated cells, and colony yield of hematopoietic progenitor cells in vitro were counted. The levels of erythropoietin, thrombopoietin, and granulocyte macrophage colony-stimulating factor in plasma were measured by enzyme-linked immunosorbent assay. Bone marrow cell cycle was performed by flow cytometry. The expression of apoptotic protein bcl-2, bax, and caspase-3 was detected by Western blotting. Results: Both Re and $Rk_3$ could improve peripheral blood cells, bone marrow nucleated cell counts, thymus index, and spleen index. Furthermore, they could enhance the yield of colonies cultured in vitro and make the levels of granulocyte macrophage colony-stimulating factor, erythropoietin, and thrombopoietin normal, reduce the ratio of $G_0/G_1$ phase cells, and increase the proliferation index. Finally, Re and $Rk_3$ could upregulate the expression of bcl-2, whereas they could downregulate the expression of bax and caspase-3. Conclusion: Re and $Rk_3$ could improve the hematopoietic function of myelosuppressed mice. The effect of $Rk_3$ was superior to that of Re at any dose. Regulating the levels of cytokines, promoting cells enter the normal cell cycle, regulating the balance of bcl-2/bax, and inhibiting the expression of caspase-3 may be the effects of Re and $Rk_3$ on myelosuppression.

• Asian Pacific Journal of Cancer Prevention
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• 제13권8호
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• pp.3803-3807
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• 2012

Prohibitin (PHB), an evolutionarily-conserved protein, has been found to be over-expressed in gastric cancer and be closely related with tumor malignancy. In this study, to investigate the relationship between PHB expression and cell apoptosis in the BGC823 gastric cancer cell line, low and high expression PHB in BGC823 cells was accomplished using RNA interference technology and gene transfer techniques. Cell proliferation, cell cycling, apoptosis, Bax, Bcl-2 and Cyt.c protein expression and the activation of Caspase-3,9 were assessed after 48h. Over-expression of PHB gene in BGC823 cells resulted in slow cell growth, cell arrest in G2 phase, and an increased apoptosis ratio while the opposite was found for PHB under-expressing cells. In PHB over-expressing cells, the expression of Bax gene was increased, the expression of Bcl-2 was decreased, the activation level of Caspase-3, 9 was increased, but the activation level of Caspase-8 demonstrated no change. These results indicate that PHB induced apoptosis through the mitochondrial pathway.

• Asian-Australasian Journal of Animal Sciences
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• 제20권2호
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• pp.153-159
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• 2007

In our previous study, overexpression of extracellular proteinase inhibitor (Expi) gene accelerated apoptosis of mammary epithelial cells, and induced expression of B cell activating factor (BAFF) gene. In this study, we found induction of BAFF-receptor (BAFF-R) gene expression in the Expi-transfected cells. A proliferation-inducing ligand (APRIL) gene is another TNF family member and the closest known relative of BAFF. We found induction of APRIL gene expression in the Expi-overexpressed apoptotic cells. NF-${\kappa}$B gene was also induced in the Expi-overexpressed cells. Expression patterns of BAFF and APRIL pathway-related genes were examined in in vivo mouse mammary gland at various reproductive stages. Expression levels of BAFF gene were very low at early pregnancy, increased from mid-pregnancy, and peaked at lactation, and thereafter decreased at involution stages of mammary gland. Expression of BAFF-R gene was highly induced in involution stages compared to lactation stages. Thus, expression patterns of BAFF-R gene were correlated to apoptotic status of mammary gland: active apoptosis of mammary epithelial cells occurs at involution stage of mammary gland. Expression levels of NF-${\kappa}$B gene were higher in involution stages compared to lactation stages. We analyzed mRNA levels of bcl-2 family genes from different stages of mammary development. Bcl-2 gene expression was relatively constant during lactation and involution stages. There was a slight increase in bcl-xL gene expression in involution stages compared to lactation state. Bax gene expression was highly induced in involution stage. Our results suggest that signaling pathways activated by both BAFF and ARRIL in mammary gland point towards NF-${\kappa}$B activation which causes upregulation of bax.

• Asian Pacific Journal of Cancer Prevention
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• 제15권24호
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• pp.10825-10830
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• 2015

The present study was conducted to investigate effects and mechanisms of action of phenolic alkaloids of Menispermum dauricum (PAMD) on gastric cancer in vivo. In vitro, cell apoptosis of human gastric cancer cell line SGC-7901 was observed using fluorescence staining. In vivo, a mice model was constructed to observe tumor growth with different doses. Cell apoptosis was examined using flow cytometry and K-RAS protein expression using Western blotting. The mRNA expression of P53, BCL-2, BAX, CASPASE-3, K-RAS was examined by real-time PCR. PAMD significantly suppressed tumor growth in the xenograft model of gastric cancer in a dose-dependent manner (p<0.01). Functionally, PAMD promoted cell apoptosis of the SGC-7901 cells and significantly increased the rate of cell apoptosis of gastric tumor cells (p<0.05). Mechanically, PAMD inhibited the expression of oncogenic K-RAS both at the mRNA and protein levels. In addition, PAMD affected the mRNA expression of the cell apoptosis-related genes (P53, BCL-2, BAX, CASPASE-3). PAMD could suppress gastric tumor growth in vivo, possibly through inhibiting oncogenic K-RAS, and induce cell apoptosis possibly by targeting the cell apoptosis-related genes of P53, BCL-2, BAX, CASPASE-3.

• Asian Pacific Journal of Cancer Prevention
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• 제14권11호
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• pp.6791-6795
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• 2013

Apoptotic and cytotoxic activity of plant extracts obtaining from naturally growing Cynara syriaca in Turkey and cultivated C cardunculus against DLD1 colorectal cancer cells was determined. Extracts from wild and cultivated Cynara species were obtained from their vegetative parts and receptacles using hexane and applied with five different dose (0.1-1 mg/ml) as well as apigenin for MTT tests for three time periods (24, 48 and 72 hours). After cells were treated with $IC_{50}$ doses for each extract total DNA and RNA were isolated for determination of the cause of cell death. From isolated RNAs, cDNA were synthesized and amplification of p21, BCL-2 and BAX gene regions was carried out. Consequently, we found that pro-apoptotic (BAX) gene expression and a cell cycle inhibitor (p21) were induced in the presence of our artichoke extracts. In contrast, anti-apoptotic BCL-2 gene expression was reduced compared to the control group. In addition DNA fragmentation results demonstrated DLD1 cell death via apoptosis.