• 생명과학회지
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• 제21권11호
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• pp.1549-1557
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• 2011

TRAIL은 다양한 암세포에서 apoptosis를 유발하는 것으로 알려져 있으나 간암세포를 포함한 일부 암세포에서 TRAIL 저항성이 획득된 것으로 보고되어지고 있다. 대두의 대표적인 생리활성 물질인 isoflavonoid계열 genistein은 이미 많은 암세포에서 apoptotic 효능을 가진 것으로 알려져 있으나 TRAIL에 의한 apoptosis 유도에 미치는 영향과 기전에 대한 연구는 여전히 미비한 실정이다. 본 연구에서는 TRAIL 저항성을 가진 Hep3B 간암세포에서 TRAIL에 의한 apoptosis 유도를 genistein이 더욱 상승시킬 수 있음을 보고하고자 한다. 본 연구의 결과에 의하면, Hep3B 세포에 세포독성을 보이지 않는 범위의 genistein에 의한 TRAIL 유도 apoptosis 상승효과는 미토콘드리아의 기능 손상과 연관성이 있었다. 또한 genistein과 TRAIL 복합처리에 의한 apoptosis 유도는 p38 MAPK 활성 저하로 더욱 상승하였으며, 이는 Bid의 truncation 증가, pro-apoptotic 단백질인 Bax의 발현 증가와 anti-apoptotic Bcl-2의 발현 감소 및 미토콘드리아에서 세포질로의 cytochrome c 유출의 증가와 연관성이 있었다. 또한 p38 MAPK 억제제는 genistein 및 TRAIL 복합처리에 의한 caspase의 활성 증가와 PARP 단백질의 단편화를 촉진시켰으며, 이는 미토콘드리아의 기능적 손상 증가에 의한 것임을 알 수 있었다. 따라서 본 연구의 결과는 genistein이 TRAIL에 의한 apoptosis 유도를 효과적으로 증가시킬 수 있으며, 이러한 과정이 p38 MAPK 의존적으로 이루어짐을 알 수 있었다.

• 생명과학회지
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• 제23권1호
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• pp.143-156
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• 2013

현재 우리나라는 높은 암 발생률과 사망률로 인해 암에 대한 관심과 심리적 불안감이 높아지고 있고, 따라서 많은 연구가 진행되고 있는 실정이다. 그럼에도 불구하고 암 발생률 빈도는 현저하게 증가하고 있는 추세이며, 그 중에서도 발병률이 높은 대장암은 발견 또한 늦어 사망률이 높다. 따라서 대장암의 예방이 무엇보다도 시급하다. 원인은 아주 다양하면서도 정확하게 규명되진 않았지만, 가장 크게 식생활의 서구화로 인한 결과로 여겨진다. 육류 위주의 서구식 식이습관 개선을 위해 식이섬유를 풍부하게 섭취하게 되면 항암제 역할을 하는 단쇄지방산인 butyrate가 위장관 내에서 장내 미생물에 의해 발생된다. 암의 치료에 있어서 항암제들은 종양세포의 apoptosis를 유도한다는 것이 알려졌고, 종양세포의 apoptosis 기전과 암의 치유기전 사이에는 서로 깊은 연관이 있음이 확인되었다. 따라서 butyrate가 직접적으로 대장암 세포의 apoptosis를 일으킴으로써 대장암을 억제하는 효과를 연구결과들을 통해서 확인하였고, 이는 대장암의 예방 및 치료에 직접적으로 영향을 미칠 것을 기대한다.

• Asian-Australasian Journal of Animal Sciences
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• 제31권8호
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• pp.1325-1335
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• 2018

Objective: This study investigated whether spermine supplementation could regulate cell cycle, apoptosis, and amino acid transporter-related genes expression in the thymus and spleen of early weaned piglets. Methods: Eighty female piglets were randomly distributed to receive adequate nutrients supplemented with spermine (0.4 mmol/kg body weight/24 h) or to be provided with restricted nourishment supplemented with normal saline for 7 h or 3, 6, or 9 d in pairs. Results: Regardless of administration time, spermine supplementation significantly up-regulated cyclin A2 gene expression but down-regulated p21 and cyclin D3 mRNA levels in the thymus and spleen and reduced cyclin E2 gene expression in the thymus of piglets (p<0.05). Irrespective of the treatment period, the reduced Bax and caspase-3 gene expressions and improved Bcl-2 mRNA level were observed in the thymus and spleen of spermine-administrated piglets (p<0.05). Regardless of supplementation time, spermine intake significantly enhanced the expressions of amino acid transporter-related genes (SLC1A1, SLC1A5, SLC7A1, SLC7A7, and SLC15A1) in both thymus and spleen, as well as SLC7A9 in the spleen of piglets (p<0.05). In addition, extended spermine administration also markedly promoted cell proliferation, depressed apoptosis and modulated amino acid transport (p<0.05), and such effects were the greatest during prolonged spermine supplementation (6 d) compared to the other time periods (p<0.05). Conclusion: Spermine supplementation may regulate cell cycle during the G1/S phase, suppress apoptosis and modulate amino acid transport. A period of 6 d of spermine supplementation is required to produce the optimal effects on nutritional implications.

• Journal of Ginseng Research
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• 제44권4호
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• pp.664-671
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• 2020

Background: Ginsenoside compound-Mc1 (Mc1) is a member of the deglycosylated ginsenosides obtained from ginseng extract. Although several ginsenosides have a cardioprotective effect, this has not been demonstrated in ginsenoside Mc1. Methods: We treated H9c2 cells with hydrogen peroxide (H₂O₂) and ginsenoside Mc1 to evaluate the antioxidant effects of Mc1. The levels of antioxidant molecules, catalase, and superoxide dismutase 2 (SOD2) were measured, and cell viability was determined using the Bcl2-associated X protein (Bax):B-cell lymphoma-extra large ratio, a cytotoxicity assay, and flow cytometry. We generated mice with high-fat diet (HFD)-induced obesity using ginsenoside Mc1 and assessed their heart tissues to evaluate the antioxidant effect and the fibrosis-reducing capability of ginsenoside Mc1. Results: Ginsenoside Mc1 significantly increased the level of phosphorylated AMP-activated protein kinase (AMPK) in the H9c2 cells. The expression levels of catalase and SOD2 increased significantly after treatment with ginsenoside Mc1, resulting in a decrease in the production of H₂O₂-mediated reactive oxygen species. Treatment with ginsenoside Mc1 also significantly reduced the H₂O₂-mediated elevation of the Bax:Bcl2 ratio and the number of DNA-damaged cells, which was significantly attenuated by treatment with an AMPK inhibitor. Consistent with the in vitro data, ginsenoside Mc1 upregulated the levels of catalase and SOD2 and decreased the Bax:B-cell lymphoma-extra large ratio and caspase-3 activity in the heart tissues of HFD-induced obese mice, resulting in reduced collagen deposition. Conclusion: Ginsenoside Mc1 decreases oxidative stress and increases cell viability in H9c2 cells and the heart tissue isolated from HFD-fed mice via an AMPK-dependent mechanism, suggesting its potential as a novel therapeutic agent for oxidative stress-related cardiac diseases.

• Journal of Ginseng Research
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• 제34권3호
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• pp.246-253
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• 2010

Ginsenoside $Rg_3$ ($Rg_3$), one of the active ingredients in Panax ginseng, attenuates NMDA receptor-mediated currents in vitro and antagonizes NMDA receptors through a glycine modulatory site in rat cultured hippocampal neurons. In the present study, we examined the neuroprotective effects of $Rg_3$ on 24-hydroxycholesterol (24-OH-chol)-induced cytotoxicity in vitro. The results showed that $Rg_3$ treatment significantly and dose-dependently inhibited 24-OH-chol-induced cell death in rat cultured cortical neurons, with an $IC_{50}$ value of $28.7{\pm}7.5\;{\mu}m$. Furthermore, the $Rg_3$ treatment not only significantly reduced DNA damage, but also dose-dependently attenuated 24-OH-chol-induced caspase-3 activity. To study the mechanisms underlying the in vitro neuroprotective effects of $Rg_3$ against 25-OH-chol-induced cytotoxicity, we also examined the effect of $Rg_3$ on intracellular $Ca^{2+}$ elevations in cultured neurons and found that $Rg_3$ treatment dose-dependently inhibited increases in intracellular $Ca^{2+}$, with an $IC_{50}$ value of $40.37{\pm}12.88\;{\mu}m$. Additionally, $Rg_3$ treatment dose-dependently inhibited apoptosis with an $IC_{50}$ of $47.3{\pm}14.2\;{\mu}m$. Finally, after confirming the protective effect of $Rg_3$ using a terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling assay, we found that $Rg_3$ is an active component in ginseng-mediated neuroprotection. These results collectively indicate that $Rg_3$-induced neuroprotection against 24-OH-chol in rat cortical neurons might be achieved via inhibition of a 24-OH-chol-mediated $Ca^{2+}$ channel. This is the first report to employ cortical neurons to study the neuroprotective effects of $Rg_3$ against 24-OH-chol. In conclusion, $Rg_3$ was effective for protecting cells against 24-OH-chol-induced cytotoxicity in rat cortical neurons. This protective ability makes $Rg_3$ a promising agent in pathologies implicating neurodegeneration such as apoptosis or neuronal cell death.

• Journal of Acupuncture Research
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• 제31권1호
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• pp.111-119
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• 2014

Objectives : I investigated whether Bee Venom can synergistically strengthen the cytotoxic effects of NK-92 cells, enhancing the inhibition of the growth of Lung Cancer Cells including A549 and NCI-H460 through induction of death receptor dependent extrinsic apoptosis and NO generation in the Nitro-oxide pathway. Methods : Bee Venom inhibited cell proliferation of A549 or NCI-H460 Human Lung Cancer Cells as well as NK-92 Cells. Moreover, when they were co-punctured with NK cells and concomitantly treated by 3 ${\mu}g/ml$ of Bee Venom, more influence was exerted on inhibition of proliferation of A549 or NCI-H460 Human Lung Cancer Cells than BV or NK cell co-culture alone. Results : The expression of Fas, TNFR2, DR3, DR6 in A549 Lung Cancer Cells was significantly increased by co-culture of NK-92 cells and treatment of 3 ${\mu}g/ml$ of Bee Venom, compared to co-culture of NK-92 cells alone, whereas the expression of Fas, TNFR2, DR6 in NCI-H460 Lung Cancer Cells was significantly increased by co-culture of NK-92 cells, representing no synergistic effects in the co-culture of NK-92 cell and concomitant treatment of 3 ${\mu}g/ml$ of Bee Venom. Coincidently, caspase-8, a expression of pro-apoptotic proteins in the extrinsic apoptosis pathway demonstrated same results as the above. Meanwhile, In NO generation, there is little change of NO generation in co-culture of NK-92 cells with A549 cells as well as the co-culture of NK-92 cell with them and concomitant treatment of 3 ${\mu}g/ml$ of Bee Venom, whereas increase of NO generation was shown in co-culture of NK-92 cells with NCI-H460 cells as well as the co-culture of NK-92 cell with them and concomitant treatment of 3 ${\mu}g/ml$ of Bee Venom, although synergistic effects by Bee Venom was not found. Conclusions : These present data provide that Bee Venom could be useful candidate compounds to enhance lung cancer growth inhibiting ability of NK-92 cells through DR expression and the related apoptosis.

• International Journal of Oral Biology
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• 제39권2호
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• pp.97-105
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• 2014

The aim of this study was to determine the beneficial effect of propofol on human keratinocytes that have undergone hypoxia reoxygenation (H/R) injury and to investigate whether autophagy is associated with the protective mechanism. Thus, we evaluated how propofol influences the intracellular autophagy and apoptosis during the H/R process in the HaCaT cells. The cultured human keratinocyte cells were exposed to 24 h of hypoxia (5% $CO_2$, 1% $O_2$, 94% $N_2$) followed by 12 h of reoxygenation (5% $CO_2$, 21% $O_2$, 74% $N_2$). The experiment was divided into 4 groups: (1) Control=Normoxia ; (2) H/R=Hypoxia Reoxygenation ; (3) PPC+H/R=Propofol Preconditioning+Hypoxia Reoxygenation; (4) 3-MA+PPC+ H/R=3-MA-Methyladenine+Propofol Preconditioning+ Hypoxia Reoxygenation. In addition, Western blot analysis was performed to identify the expression of apoptotic pathway parameters, including Bcl-2, Bax, and caspase 3 involved in mitochondrial-dependent pathway. Autophagy was determined by fluorescence microscopy, MDC staining, AO staining, and western blot. The H/R produced dramatic injuries in keratinocyte cells. In our study, the viability of Propofol in H/R induced HaCaT cells was first studied by MTT assay. The treatment with 25, 50, and $100{\mu}M$ Propofol in H/R induced HaCaT cells enhanced cell viability in a dose-dependent manner and $100{\mu}M$ was the most effective dose. The Atg5, Becline-1, LC3-II, and p62 were elevated in PPC group cells, but H/R-induced group showed significant reduction in HaCaT cells. The Atg5 were increased when autophagy was induced by Propofol, and they were decreased when autophagy was suppressed by 3-MA. These data provided evidence that propofol preconditioning induced autophagy and reduced apoptotic cell death in an H/R model of HaCaT cells, which was in agreement with autophagy playing a very important role in cell protection.

• Journal of Ginseng Research
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• 제41권3호
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• pp.392-402
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• 2017

Background: Previously, we reported that Korean Red Ginseng inhibited liver fibrosis in mice and reduced the expressions of fibrogenic genes in hepatic stellate cells (HSCs). The present study was undertaken to identify the major ginsenoside responsible for reducing the numbers of HSCs and the underlying mechanism involved. Methods: Using LX-2 cells (a human immortalized HSC line) and primary activated HSCs, MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide) assays were conducted to examine the cytotoxic effects of ginsenosides. $H_2O_2$ productions, glutathione contents, lactate dehydrogenase activities, mitochondrial membrane permeabilities, apoptotic cell subpopulations, caspase-3/-7 activities, transferase dUTP nick end labeling (TUNEL) staining, and immunoblot analysis were performed to elucidate the molecular mechanism responsible for ginsenoside-mediated cytotoxicity. Involvement of the AMP-activated protein kinase (AMPK)-related signaling pathway was examined using a chemical inhibitor and small interfering RNA (siRNA) transfection. Results and conclusion: Of the 11 ginsenosides tested, 20S-protopanaxadiol (PPD) showed the most potent cytotoxic activity in both LX-2 cells and primary activated HSCs. Oxidative stress-mediated apoptosis induced by 20S-PPD was blocked by N-acetyl-$\text\tiny L$-cysteine pretreatment. In addition, 20S-PPD concentration-dependently increased the phosphorylation of AMPK, and compound C prevented 20S-PPD-induced cytotoxicity and mitochondrial dysfunction. Moreover, 20S-PPD increased the phosphorylation of liver kinase B1 (LKB1), an upstream kinase of AMPK. Likewise, transfection of LX-2 cells with LKB1 siRNA reduced the cytotoxic effect of 20S-PPD. Thus, 20S-PPD appears to induce HSC apoptosis by activating LKB1-AMPK and to be a therapeutic candidate for the prevention or treatment of liver fibrosis.

• 생명과학회지
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• 제21권1호
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• pp.89-95
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• 2011

식품에서 추출한 파이토케미컬은 여러 암종에서 암세포의 증식억제와 apoptosis를 유도한다. 최근에 이러한 파이토케미컬의 세포 내 신호전달 기작에 관한 관심이 높아지고 있으며, 본 연구에서는 파이토케미컬의 일종인 커큐민과 EGCG를 HCT116 대장암세포에 처리함으로써 암세포의 증식억제와 apoptosis 유도 효과를 알아보고, 암세포의 증식에 관여하는 Akt의 활성과 종양 억제유전자인 p53의 신호경로를 규명하고자 하였다. 그 결과, 커큐민과 EGCG를 처리했을 때 HCT116 세포의 증식이 억제되었고, 암세포에서 apoptosis 효과가 나타남을 확인하였다. 동일한 조건에서 Western blotting을 실시했을 때 Akt의 활성은 감소하였으며 p53의 발현은 증가하였다. 또한 Akt의 저해제인 LY294002를 처리했을 때 암세포의 증식이 더욱 강하게 억제되었으며, p53의 발현은 더욱 강하게 증가하는 것으로 나타났다. 따라서 HCT116 세포에서 커큐민과 EGCG 처리에 의한 암세포의 증식 억제 및 apoptosis는 p53의 발현이 증가함에 따라 유도되며, 이러한 p53의 발현 증가는 Akt 신호경로를 저해함으로써 일어난다는 것을 확인하였다.

• Journal of Microbiology and Biotechnology
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• 제22권12호
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• pp.1665-1672
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• 2012

An 80% ethanol extract of Hizikia fusiforme was obtained and followed by successive fractionation using the organic solvents n-hexane, ethyl acetate, and n-butanol to identify the antioxidative substance. The aqueous part of the nbutanol fractionation step, showing high antioxidative activity, was subjected to reverse-phase liquid chromatography. As a result, a substance purified from a BB-2 fraction showed high antioxidative activity. The m/z 419 [M+H] molecular ion peak in the fraction was observed by the analysis of the ESI-LC/MS spectrum. By the analysis of 1H NMR (500 MHz, DMSO-$d_6$) and $^{13}C$ NMR (125 MHz, DMSO-$d_6$) spectra, a unique compound of the fraction was biochemically identified as a 5-hydroxy-3,6,7,8,3',4'-hexamethoxyflavone (5HHMF). We also investigated the effect of 5HHMF on human gastric AGS carcinoma cells. Western blot analysis suggested that the flavone substantially increased the levels of the death receptor-associated apoptosis mediators Fas, Fas L, FADD, TRADD, and DR4 in a concentration-dependent manner. The levels of Fas, Fas L, TRADD, and DR4 in the cells treated with 5HHMF ($5{\mu}g/ml$) were approximately 26.4-, 12.8-, 6.7-, and 9.8-times higher than those of non-treated cells, respectively. Of note, the level of FADD protein in the cells exposed to 5HHMF ($1{\mu}g/ml$) increased approximately 9.6-times. In addition, the cleavage of caspase-3, -8, and -9 in cultured AGS cells treated with 5HHMF was significantly confirmed. Therefore, our results suggest that 5HHMF from H. fusiforme is involved in the induction of death receptor-associated apoptosis mediators in human gastric AGS carcinoma cells.