• Molecules and Cells
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• 제21권1호
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• pp.7-20
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• 2006

The major event in human immunodeficiency virus type 1 (HIV-1) infection is the death of many cells related to host immune response. The demise of these cells is normally explained by cell suicide mechanism, apoptosis. Interestingly, the decrease in the number of immune cells, such as non-CD4+ cells as well as CD4+ T cells, in HIV infection usually occurs in uninfected bystander cells, not in directly infected cells. It has, therefore, been suggested that several soluble factors, including viral protein R (Vpr), are released from the infected cells and induce the death of bystander cells. Some studies show that Vpr interacts directly with adenine nucleotide translocator (ANT) to induce mitochondrial membrane permeabilization (MMP). The MMP results in release of some apoptogenic factors such as cytochrome-c (cyt-c) and apoptosis-inducing factor (AIF). Vpr also has indirect effect on mitochondria through enhancing the level of caspase-9 transcription and suppressing nuclear factor-kappa B (NF-${\kappa}B$). The involvement of p53 in Vpr-induced apoptosis remains to be studied. On the other hand, low level of Vpr expression has anti-apoptotic effect, whereas it's high level of expression induces apoptosis. Extracellular Vpr also exhibits cytotoxicity to uninfected bystander cells through apoptotic or necrotic mechanism. The facts that Vpr has cytotoxic effect on both infected cells and bystander cells, and that it exhibits both proand anti-apoptotic activity may explain its role in viral survival and disease progression.

• 생명과학회지
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• 제27권5호
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• pp.545-552
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• 2017

Julbernardia globiflora는 미옴보 숲에 널리 분포하는 열대 아프리카 나무로, 우울증, 위장장애 등의 치료를 위해 민간요법으로 사용되고 있으나, 항산화능, 항암 활성 등에 대한 연구는 알려진 바가 없다. 따라서 본 연구에서는 J. globiflora 메탄올 추출물(MEJG)을 사용하여 항산화능 및 인체 대장암 세포주인 HT29에 대한 항암 활성에 관하여 분석하였다. 먼저 DPPH radical scavenging activity를 통해 분석한 결과, MEJG의 $IC_{50}$는 $1.23{\mu}g/ml$로 강력한 항산화능을 보유하였음을 확인하였다. 또한 MEJG 농도 의존적으로 HT29 세포의 성장을 억제하였다. MEJG의 HT29 세포 사멸 효과의 기전을 분석하기 위하여 Annexin V 염색과 DAPI 염색을 수행한 결과, 대조군에 비하여 apoptotic 세포 및 apoptotic body가 증가됨을 확인하였다. 또한 apoptosis 관련 단백질들의 발현변화를 분석한 결과, MEJG처리에 의해 사멸수용체인 Fas와 pro-apoptotic 단백질인 Bax의 발현이 증가되었으며, anti-apoptotic 단백질인 Bcl-2의 발현이 감소하였다. 이러한 결과로 cytochrome c가 미토콘드리아에서 세포질로 방출되어 증가되었으며, caspase-3, -8, -9가 활성화되었다. 최종적으로 PARP가 분해되어 apoptosis가 유도되었음을 확인하였다. 이러한 결과들로부터 MEJG는 내인성 및 외인성 경로를 통한 apoptosis 유도에 의하여 HT29 세포의 증식을 억제하는 항암활성을 보유하였음을 확인하였다.

• BMB Reports
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• 제38권6호
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• pp.639-645
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• 2005

Protein kinase C (PKC) isozymes, a family of serine-threonine kinases, are important regulators of cell proliferation and malignant transformation. Phorbol esters, the prototype PKC activators, cause PKC translocation to the plasma membrane in prostate cancer cells, and trigger an apoptotic response. Studies in recent years have determined that each member of the PKC family exerts different effects on apoptotic or survival pathways. $PKC{\delta}$, one of the novel PKCs, is a key player of the apoptotic response via the activation of the p38 MAPK pathway. Studies using RNAi revealed that depletion of $PKC{\delta}$ totally abolishes the apoptotic effect of the phorbol ester PMA. Activation of the classical $PKC{\alpha}$ promotes the dephosphorylation and inactivation of the survival kinase Akt. Studies have assigned a pro-survival role to $PKC{\varepsilon}$, but the function of this PKC isozyme remains controversial. Recently, it has been determined that the PKC apoptotic effect in androgen-dependent prostate cancer cells is mediated by the autocrine secretion of death factors. $PKC{\delta}$ stimulates the release of $TNF{\alpha}$ from the plasma membrane, and blockade of $TNF{\alpha}$ secretion or $TNF{\alpha}$ receptors abrogates the apoptotic response of PMA. Molecular analysis indicates the requirement of the extrinsic apoptotic cascade via the activation of death receptors and caspase-8. Dissecting the pathways downstream of PKC isozymes represents a major challenge to understanding the molecular basis of phorbol ester-induced apoptosis.

• 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.

• 동의생리병리학회지
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• 제21권6호
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• pp.1437-1449
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• 2007

In this study, the effect of extract of Corydalis yanhusuo (ECT) used in Oriental medicine therapy was investigated on the cell growth and apoptosis of HepG2 human hepatoma cells. It was found that ECT could inhibit the cell growth effectively in a dose-dependent manner, which was associated with morphological change and apoptotic cell death such as formation of apoptotic bodies, DNA fragmentation and increased populations of apoptotic-sub G1 phase. And we observed the effects of ECT on loss of mitochondrial membrane potential (MMP), using the JC-1 probe by DNA flow cytometric analysis. Apoptosis of HepG2 cells by ECT was associated with a down-regulation of anti apoptotic Bcl-2 expression, inhibitor of apoptosis proteins (IAPs) expression and proteolytic activation of caspase-3 and caspase-9. However, ECT did not affect the pro-apoptotic Bax expression and activity of caspase-8. ECT treatment also concomitant degradation and /or inhibition of poly (ADP-ribose) polymerase (PARP), phospholipase C-1 ($PLC{\gamma}1$). Furthermore, ECT treatment caused a dose-dependent inhibition of iNOS and cyclooxygenase-2 (Cox-2). Additionally ECT have been implicated in the regulation of telomerase expression. ECT treatment induced the down-regulation of telomerase reverse transcriptase mRNA (hTERT) expression of HepG2 cells. Taken together, these findings suggest that ECT may be a potential chemotherapeutic agent for the control of HepG2 human hepatoma cells.

• 대한본초학회지
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• 제27권4호
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• pp.45-51
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• 2012

Objectives : WHW is a polyherbal medicine for the treatment of chronic renal failure (CRF). WHW previously reported various biological property such as anti-inflammation, anti-oxidation and anti-renal fibrosis in CRF. This study aimed to investigate the anti-apoptotic effect of WHW on staurosporin(SSP)-induced apoptosis in canine kidney epithelial cells (MDCK). Methods : MDCK cells were treated with different concentrations of WHW (0.1, 0.2, 0.5 and $1mg/m{\ell}$) for 1 h, and then induced apoptosis by treatment of SSP ($1{\mu}M$) for 24 h. Cell viability was measured by WST-1 assay. The expression of apoptotic proteins such as caspase-3, Bax and Bcl-2 was determined by Western blot. Caspase-3 activity and ROS levels were also measured by their commercial available assay kits. Cell apoptosis was observed by Hoechst and DNA fragmentation. Results : WHW significantly increased the cell viability on SSP-treated MDCK cells. WHW inhibited SSP-induced expression of apoptotic proteins such as caspase-3 and Bax, and significantly decreased caspase-3 activity in MDCK cells. WHW significantly decreased SSP-induced production of ROS, and suppressed SSP-induced chromatin condensation and DNA fragmentation in MDCK cells. Conclusions : These results suggest that WHW has an anti-apoptotic effect in renal cells through suppressing the expression of apoptotic proteins, ROS production and DNA damages.

• 대한한방부인과학회지
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• 제28권2호
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• pp.40-54
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• 2015

Objectives : In the theory of Korean medicine, Citri Reticulatae Viride Pericarpium (CRVP) can soothe the liver to break qi stagnation, eliminate mass and relieve dyspepsia. This study was carried out to investigate the effects of CRVP on the apoptotic cell death in breast cancer cells. Methods : In the present experiment, the effects of CRVP on proliferation rates, type of cell death, cell cycle distribution, and intracellular oxidative stress were investigated using MDA-MB-231 cells in vitro. In addition, the effects on expression levels of caspase 3, caspase 9, Bax and Bcl-2 were also investigated. Results : Treatment with CRVP decreased proliferation rates in a dose dependent manner. ID50 (50% inhibitory dosage) was 175.4 μg/ml. In the CRVP treated group, cell volumes showed smaller than non-treated normal. In addition, CRVP increased percentage of apoptotic and sub G1 arrested cells respectively. 200 μg/ml of CRVP treatment increased intracellular ROS level significantly. Finaly the expression level of caspase 3 and Bax/Bcl-2 ratio were elevated by treatment with CRVP respectively. Conclusions : These results suggest that CRVP can trigger intrinsic apoptotic pathway in MDA-MB-231 cells.

• International Journal of Oral Biology
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• 제37권3호
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• pp.91-102
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• 2012

Bcl-2 protects tumor cells from the apoptotic effects of various anti-neoplastic agents. Increased expression of Bcl-2 has been associated with a poor response to chemotherapy in various malignancies, including leukemia. Hence, bypassing the resistance conferred by anti-apoptotic factors such as Bcl-2 represents an attractive therapeutic strategy against cancer cells, including leukemic cells. This study was undertaken to examine whether the anticancer drug, cisplatin and the synthetic chenodeoxycholic acid (CDCA) derivative, HS-1200 show anti-tumor activity in U937 and U937/Bcl-2 cells. Viability assays revealed that HS-1200 overcomes the resistance conferred by Bcl-2 in human leukemic U937 cells. Various apoptosis assessment assays further demonstrated that HS-1200 overcomes the resistance conferred by Bcl-2 in human leukemic U937 cells by inducing apoptosis. In addition HS-1200, but not cisplatin, overcomes the anti-apoptotic effects of Bcl-2 in Bcl-2 over-expressing human leukemic cells (U937/Bcl-2 cells). Notably, we observed that the HS-1200-induced formation of mature promyelocytic leukemia (PML) nuclear bodies (NBs) correlates with a suppression of the anti-apoptotic effects of Bcl-2 in human leukemic cells over-expressing this protein (U937/Bcl-2 cells). Furthermore, HS-1200 was found to induce the association between PML and SUMO-1, Daxx, Sp100, p53 or CBP in the aggregated PML-NBs of U937/Bcl-2 cells. Thus, PML protein and the formation of mature PML-NBs could be considered as therapeutic targets that may help to bypass the resistance to apoptosis conferred by Bcl-2. Elucidating the exact mechanism by which PML regulates Bcl-2 will require further work.

• 한방안이비인후피부과학회지
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• 제22권2호
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• pp.50-59
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• 2009

Objectives : The aim of this study was conducted that CRE (Coptidis Rhizoma Extract) induces apoptosis in YD-10B cells, human oral squamous carcinoma cell line. Methods : In this study, YD-10B cells were exposed to CRE (0.03-0.30 mg/ml), for 6-24 hours. We measured the effects of CRE on the changes of cell viability and cell membrane, TUNEL assay of CRE-treated YD-10B cell. Results : In this study, CRE caused a decrease of viability in YD-10B cells, human oral squamous carcinoma cell line. When YD-10B cells were treated with CRE, cells showed dose-dependent manner apoptotic cell death. Conclusions : These results suggest that CRE may be potential therapeutic approach in the clinical management of oral squamous cell carcinoma.

• 대한의생명과학회지
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• 제29권3호
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• pp.201-205
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• 2023

Free adenine is mainly made during the polyamine synthesis in proliferating cells. Adenine molecule itself acts biological modulator in inflammation and cell death. In the previous report, we showed that adenine induces apoptotic cell death of B16-F10 mouse melanoma cells by eliciting of PARP and caspase 3 cleavages. In this study, we examined the adenine effect on other apoptotic molecules affecting caspase activation in B16-F10 melanoma cells. Adenine treatment make pro-apoptotic molecules active states. Bax/Bcl-2 ratio was increased and phosphorylation of mTOR and Akt was decreased in a dose dependent manner. These results showed the possibility that Bax/Bcl-2, Akt and mTOR are engaged in adenine induced apoptosis of melanoma cells.