• 한국어병학회지
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• 제16권1호
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• pp.39-49
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• 2003

Cytosolic oxidation by 4-hydroxy-2-nonenal (4HNE) and tert-butyl hydroperoxide (t-BHP) results in cell death of bovine aortic endothelial cells (BAEC). In this study, we have investigated the roles of antioxidants such as 2,3,6-tribromo-4,5-dihydroxy benzyl methyl ether (TDB) and phloroglucinol in preventing cell death. After treatment with oxidants for 6h, cells became compact and showed nuclear condensation, which were characteristics of early apoptosis. After l2h treatment, morphologic features including severe cytoplasm condensation, membrane blebbing, and apoptotic bodies were prominent and these findings were interpreted as characteristics of late-apoptosis. When the apoptotic cells were treated with antioxidants for 12h, both early and late apoptotic cells did show no significant change. After oxidant treated cells were incubated with antioxidant for 24h, the characteristics of early-apoptosis were eliminated but cells in lateapoptosis could not return to normal cells. These results suggest that TDB and phloroglucinol prevent the cells from dying through apoptosis induced by 4HNE and t-BHP in early stage.

• 생명과학회지
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• 제25권1호
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• pp.93-100
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• 2015

Pachymic acid는 복령에서 분리된 lanostane-type인 triterpenoid의 일종이다. 최근 pachymic acid가 항암 및 항염증 효능과 산화적 스트레스에 대한 항산화 효능 등과 같은 약리적인 효능이 있는 것으로 밝혀지고 있으나, 그에 대한 구체적인 분자생물학적 기전 연구는 매우 미비한 실정이다. 본 연구에서는 pachymic acid의 항암활성 및 관련 기전 조사의 일환으로 T24 인체 방광암세포 모델을 이용하여 pachymic acid에 의한 apoptosis 유발 여부를 검증하였다. 본 연구의 결과에 의하면 pachymic acid는 T24 세포의 증식을 유의적으로 억제시켰으며, 이는 apoptosis 유발과 연관성이 있음을 다양한 방법으로 확인하였다. Pachymic acid에 의한 apoptosis 유도에는 pro-apoptotic 인자들의 발현 증가와 anti-apoptotic 유전자 산물들의 발현 감소가 동반되었으며, MMP의 소실과 tBid의 발현 증가가 관찰되었다. 아울러 pachymic acid는 extrinsic 및 intrinsic apoptosis 경로의 개시에 관여하는 caspase-8 및 -9의 활성뿐 만 아니라, caspase-3의 활성도 증가시킴으로서 PARP와 같은 기질 단백질의 단편화를 초래하였다. 따라서 pachymic acid는 항암활성을 지니는 천연생리활성 물질로서의 잠재력이 매우 높음을 알 수 있었다.

• 생명과학회지
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• 제26권7호
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• pp.847-854
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• 2016

Nucleoside adenosine 유도체의 하나인 cordycepin (3′-deoxyadenosine)은 Cordyceps 속에서 유래된 활성 물질 중의 하나로서 항염증, 항산화 및 항암활성을 포함한 다양한 약리학적 효능이 있는 것으로 잘 알려져 있다. 본 연구에서는 AGS 인체 위암세포의 증식에 미치는 cordycepin의 영향과 관련 기전 연구를 시도하였다. Cordycepin의 처리에 따라 AGS 세포의 생존율이 처리 농도 의존적으로 감소되었으며, DNA 단편화 및 flow cytometery 분석에 따른 apoptosis 유발 또한 유의적으로 증가하였음을 확인하였다. 이러한 cordycepin 처리에 따른 AGS 세포의 apoptosis 유도에는 TRAIL, DR5 및 FasL의 mRNA 및 단백질의 발현 증가가 연관되어 있었다. 아울러 cordycepin은 Bcl-2 family 중 pro-apoptotic 인자인 Bax의 발현은 증가시켰으며, anti-apoptotic 인자인 Bcl-2 및 Bcl-xL의 발현은 전사 및 번역 수준에서 억제시켰다. 이러한 현상들은 extrinsic 및 intrinsic apoptosis의 initiator caspase (caspase-8 및 -9) 뿐만 아니라 effector caspase인 caspase-3의 활성과 PARP 단백질의 절단 증가와 연관성이 있었다. 따라서 AGS 세포에서 cordycepin에 의한 apoptosis의 유발은 death receptor 활성과 mitochondria 기능 손상을 포함한 multiple apoptotic pathway가 관여할 것으로 생각된다. 비록 좀 더 세심한 기전 연구의 결과가 뒤따라야 되겠지만, 본 연구의 결과는 cordycepin의 항암작용을 이해하는데 중요한 자료가 될 것이며 향후 수행될 추가 실험을 위한 기초 자료로서 그 가치가 매우 높을 것으로 생각된다.

• Journal of Ginseng Research
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• 제44권1호
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• pp.79-85
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• 2020

Background: Helicobacter pylori increases reactive oxygen species (ROS) and induces oxidative DNA damage and apoptosis in gastric epithelial cells. DNA damage activates DNA damage response (DDR) which includes ataxia-telangiectasia-mutated (ATM) activation. ATM increases alternative reading frame (ARF) but decreases mouse double minute 2 (Mdm2). Because p53 interacts with Mdm2, H. pylori-induced loss of Mdm2 stabilizes p53 and induces apoptosis. Previous study showed that Korean Red Ginseng extract (KRG) reduces ROS and prevents cell death in H. pylori-infected gastric epithelial cells. Methods: We determined whether KRG inhibits apoptosis by suppressing DDRs and apoptotic indices in H. pylori-infected gastric epithelial AGS cells. The infected cells were treated with or without KRG or an ATM kinase inhibitor KU-55933. ROS levels, apoptotic indices (cell death, DNA fragmentation, Bax/Bcl-2 ratio, caspase-3 activity) and DDRs (activation and levels of ATM, checkpoint kinase 2, Mdm2, ARF, and p53) were determined. Results: H. pylori induced apoptosis by increasing apoptotic indices and ROS levels. H. pylori activated DDRs (increased p-ATM, p-checkpoint kinase 2, ARF, p-p53, and p53, but decreased Mdm2) in gastric epithelial cells. KRG reduced ROS and inhibited increase in apoptotic indices and DDRs in H. pylori-infected gastric epithelial cells. KU-55933 suppressed DDRs and apoptosis in H. pylori-infected gastric epithelial cells, similar to KRG. Conclusion: KRG suppressed ATM-mediated DDRs and apoptosis by reducing ROS in H. pylori-infected gastric epithelial cells. Supplementation with KRG may prevent the oxidative stress-mediated gastric impairment associated with H. pylori infection.

• 동의생리병리학회지
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• 제20권6호
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• pp.1664-1671
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• 2006

Cisplatin is a anti-neoplastic agent which is commonly used for the treatment of solid tumor. Cisplatin activates multiple signal transduction pathways involved in the stress-induced apoptosis in a variety of cell types. Cytotoxicity of cisplatin was detected in rat mesangial cells and the value of $IC_{50}$ is about 20 ${\mu}M$. The treatment of cisplatin to rat mesangial cells showed the apoptotic bodies and DNA fragmentation. The activation of caspase-3, -8, and -9 and proteolytic cleavage of PARP were observed in the rat mesangial cells treated time-dependently with cisplatin. The activation of ERK, p38 and JNK was also observed in the apoptosis induced by cisplatin in rat mesangial cells. The ethanol extract of Bojungbangam-tang (EBJT), a new hergal prescription composed of nine crude drugs, inhibited cisplatin-induced apoptosis in rat mesangial cells. EBJT reduced sub-G1 peak (apoptotic peak) in cisplatin-treated rat mesangial cells. The cisplatin-induced ERK and JNK activation in rat mesangial cells were blocked by EBJT, but EBJT had no effect on p38 activation. Taken together, these results con suggest that EBJT prevents cisplatin-induced apoptotic cell death in rat mesangial cells through inhibition of ERK and JNK activation.

• 대한의생명과학회지
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• 제8권3호
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• pp.161-165
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• 2002

Apoptosis can be difficult to detect in routine histological sections. Since extensive DNA fragmentation is an important characteristic of this process, visualization of DNA breaks could greatly facilitate the identification of apoptotic cells. Several techniques for the qualitative and quantitative detection of this process have been established; recently, an in situ nick end-labelling technique based on the detection of DNA fragmentation, which is a molecular characteristic of apoptotic cell death, was described. Applying this method to paraffin sections of rat tissues, sensitivity was observed to be inconsistently low with regard to the expected number of apoptotic cells. I describe a new modified method for formalin-fixed, paraffin-embedded tissue sections, pretense pretreatment to permeate the tissue sections that involves an TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling) is acknowledged as a method of choice in the rapid identification and quantification of the apoptotic cell fraction in paraffin tissue preparations. TUNEL was performed without apoptosis and with apopotosis samples to each of the three concentrations of proteinase K (10, 25, 40 mg/ml) pretreatments. In this study, I show that chemical pretreatments of the tissue sections in proteinase K (25 mg/ml for 15 min at room temperature) considerably enhances the sensitivity of this nick end labelling technique.

• Molecules and Cells
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• 제28권6호
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• pp.509-513
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• 2009

Here, we show that JNK1 and JNK3 have different roles in ${\alpha}-$ or etoposide-induced apoptosis in HeLa cells. Dominant negative JNK1 inhibited $TNF-{\alpha}-$ or etoposide-induced apoptosis, while dominant negative JNK3 promoted $TNF-{\alpha}-$ or etoposide-induced apoptosis. During $TNF-{\alpha}$-induced apoptosis, JNK1 was activated in a biphasic manner, exhibiting both transient and sustained activity, whereas JNK3 was activated early and in a transient manner. The role of JNK3 activation was an anti-apoptotic effect, while the role of JNK1 activation was a pro-apoptotic effect. These results suggest that the anti-apoptotic mechanism of JNK3 in $TNF-{\alpha}$-induced apoptosis originates before the apoptotic machinery is triggered.

• 동의생리병리학회지
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• 제22권2호
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• pp.403-409
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• 2008

In Oriental medicine daeseungki-tang is one of the prescription that is used clinically for constipation of paralytics. The objective of the study was to observe the effect of daeseungki-tang on apoptotic neuronal cell death. In the present study, middle cerebral artery occlusion(MCAO) rats were treated with daeseungi-tang for 5 days and the edema percentage of cerebral hemisphere of MCAO rats were investigated primary. Secondary, appearances of Bax, Bcl-2,-factors that is related to apoptotic neuronal cell death - and HSP72 in the brain of MCAO rats were investigated via immunohistochemistry. Daeseungki-tang significantly decreased edema percentage of the cerebral hemisphere of MCAO rats. Daeseungki-tang significantly decreased Bax positive cells, but did not change the apperances of Bcl-2 positive cells in the penumbra of the cerebral cortex and the caudoputamen of MCAO rats. Daeseungki-tang significantly decreased HSP72 positive cells in the penumbra of the cerebral cortex, but not in the caudoputamen of MCAO rats. Based on the present results, it can be suggested that treatment with daeseungki-tang may decrease edema of the cerebral hemisphere and restrain apoptotic neuronal cell death in the penumbra of the cerebral cortex.

• 대한약침학회지
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• 제18권2호
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• pp.26-32
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• 2015

Objectives: Rheum undulatum L. has traditionally been used for the treatment of many diseases in Asia. However, its anti-proliferative activity in cancer has still not been studied. In the present study, we investigated the anti-cancer effects of methanol extract of Rheum undulatum L. (MERL) on human adenocarcinoma gastric cell lines (AGS). Methods: To investigate the anti-cancer effect of MERL on AGS cells, we treated the AGS cells with varying concentrations of MERL and performed 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assays. Cell cycle analyses, measurements of the mitochondrial membrane potential (MMP), caspase activity assays and Western blots were conducted to determine whether AGS cell death occurred by apoptosis. Results: Treatment with MERL significantly inhibited growth of AGS cells in a concentration dependent manner. MERL treatment in AGS cells leaded to increased accumulation of apoptotic sub G1 phase cells in a concentration dependent manner. In control cultures, 5.38% of the cells were in the sub G1 phase. In MERL treated cells, however, this percentage was significantly increased (9.95% at $70{\mu}g/mL$, 15.94% at $140{\mu}g/mL$, 26.56% at $210{\mu}g/mL$ and 38.08% at $280{\mu}g/mL$). MERL treatment induced the decreased expression of pro-caspase-8 and -9 in a concentration dependent manner, whereas the expression of the active form of caspase-3 was increased. A subsequent Western blot analysis revealed increased cleaved levels of poly (ADP-ribose) polymerase (PARP) protein. Also, treatment with MERL increased the activities of caspase-3 and -9 compared with the control. MERL treatment increased the levels of the pro-apoptotic truncated Bid (tBid) and Bcl2 Antagonist X (Bax) proteins and decreased the levels of the anti-apoptotic B-cell lymphoma 2 (Bcl-2) protein, whose is the stabilization of mitochondria. However, inhibitions of p38, extracellular signal regulated kinases (ERKs) and C-Jun N-terminal kinases (JNK) by MERL treatment did not affect cell death. Conclusion: These results suggest that MERL mediated cell death is associated with an intrinsic apoptotic pathway in AGS cells.

• Toxicological Research
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• 제16권2호
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• pp.133-139
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• 2000

This study was designed to evaluate the mechanism by which reactive nitrogen intermediates (RNI) induced the cytotoxicity of human doparminergic neuroblastoma SH-SY5Y cells. 3-Morpholino-sydnonimine (SIN-l), a donor of peroxynitrite (ONOO) and sodium nitroprusside (SNP), a donor of nitric oxide (NO) induced cell detachment and apoptotic death, as characterized by chromatin condensation, the ladder pattern fragmentation of genomic DNA and morphological nuclear changes. SIN-l also induced the activation of caspase 3-like protease in a time-dependent manner. Exogenous antioxidants, such as reduced glutathione (GSH), N-acetylcysteine (NAC), and selenium protected the cells from apoptotic death and reduced the activation of caspase 3-like protease by SIN-1. Furthermore, SIN-l directly reduced the intracellular levels of glutathione. Taken together, these data suggested that RNI including NO and peroxynitrite decrease the concentration of intracellular antioxidant such as GSH, which lead to the apoptotic death of human neuroblastoma SH-SY5Y cells.