scholarly journals Mitigation of H2O2-Induced Mitochondrial-Mediated Apoptosis in NG108-15 Cells by Novel Mesuagenin C fromMesua kunstleri(King) Kosterm

2012 ◽  
Vol 2012 ◽  
pp. 1-18 ◽  
Author(s):  
Gomathi Chan ◽  
Muhamad Noor Alfarizal Kamarudin ◽  
Daniel Zin Hua Wong ◽  
Nor Hadiani Ismail ◽  
Faizuri Abdul Latif ◽  
...  

This study was aimed to isolate and evaluate neuroprotective compounds from the hexane extract of the bark ofMesua kunstleri(Clusiaceae) on H2O2-induced apoptosis in NG108-15 cells. Five 4-phenylcoumarins were isolated by using various chromatographic techniques via neuroprotective activity-guided fractionation and isolation from the active hexane extract. The chemical structures of the isolated compounds were confirmed by NMR spectroscopic data interpretation and comparison with literature values. Cell viability data demonstrated that mesuagenin C3significantly increased cell viability. Hoechst 33342/PI staining illustrated mesuagenin C3was able to abate the nuclear shrinkage, chromatin condensation and formation of apoptotic bodies. Pretreatment with mesuagenin C3reduced total annexin V positive cells and increased the level of intracellular glutathione (GSH). Mesuagenin C3attenuated membrane potential (Δψm), reduced Bax/Bcl-2 ratio and inactivated of caspase-3/7 and -9. These results indicated that mesuagenin C3could protect NG108-15 cells against H2O2-induced apoptosis by increasing intracellular GSH level, aggrandizingΔψm, and modulating apoptotic signalling pathway through Bcl-2 family and caspase-3/7 and -9. These findings confirmed the involvement of intrinsic apoptotic pathway in H2O2-induced apoptosis and suggested that mesuagenin C3may have potential therapeutic properties for neurodegenerative diseases.

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 1872-1872
Author(s):  
Mo Yang ◽  
Shing Chan ◽  
Yiu Fai Cheung ◽  
Shau Yin Ha ◽  
Godfrey ChiFung Chan

Abstract Cardiomyopathy and liver damage due to iron-overload are the major complications in patients with beta-thalassaemia major. Iron-overload may induce apoptosis in cardiomyocytes and hepatic cells, and that TPO may exert protective effect on apoptosis of cardiomyocytes (Circulation, 2006). In this study, we demonstrated firstly that iron induced apoptosis in cardiomyocytes. Using H9C2 cells, we have shown that iron reduced cell viability in a dose-dependent manner (0.003–3 mM) (n=6). By annexin V and PI staining, apoptotic cells were found to be significantly increased after iron treatment (0.3 mM, 72 hrs) (n=6). The expression of active caspase-3 was significantly increased in iron-treated cells. Furthermore, iron treatment increased the proportion of cells containing JC-1 monomers, indicating a trend in the drop of mitochondrial membrane potential (n=6). Secondly, we found that TPO exerted cardio-protective effect on iron-induced apoptosis. H9C2 cells were cultured in the presence of iron (0.3 mM) with or without TPO (5, 10, 20, 50, 100 ng/mL, 72 hrs). The cell viability was significantly increased with the treatment of TPO at 50 ng/mL and 100 ng/mL (n=4). Dot-plot analysis of annexin V/PI staining demonstrated that TPO (50 ng/mL) significantly reduced the population of apoptotic cells (n=6). Incubation with TPO also decreased the iron-induced caspase-3 expression (n=6). Flow cytometric dot-plot analysis of H9C2 cells also showed trends of amelioration of the increase in JC-1 monomers in the iron plus TPO group (n=6). The population of phospho-Akt and Erk1/2 were also significantly increased after treatment by TPO (P<0.05, n=4). Human liver cell line MIHA was also used as a cell model. We showed that iron-overload reduced cell viability in a dose-dependent manner (0.0375–0.6 mM) (n=7). By annexin V and PI staining, apoptotic cells were found to be significantly increased after iron treatment (0.15–0.6 mM) for 72 hrs (n=7). The expression of active caspase-3 was also significantly increased in iron-treated cells (n=5). We also found that TPO exerted proliferation effect on MIHA cell by activation of phospho-Akt. However, MIHA cells were cultured in the presence of iron (0.3 mM) with TPO (50 ng/mL, 72 hrs). The cell viability was not significantly increased with the treatment of TPO (n=5). Dot-plot analysis of annexin V/PI staining did not demonstrated that TPO reduced the population of apoptotic cells induced by iron-overload (n=5). Also, incubation with TPO did not decrease the iron-induced caspase-3 expression in these cells (n=5). Our findings suggest that iron-overload induces apoptosis in cardiomyocytes and hepatocytes via mitochondrial/caspase-3 pathways and that TPO might exert a protective effect on iron-overload induced apoptosis via the activation of Akt and Erk1/2 pathways in cardiomyocytes.


2001 ◽  
Vol 280 (5) ◽  
pp. H2292-H2299 ◽  
Author(s):  
Guang-Wu Wang ◽  
Zhanxiang Zhou ◽  
Jon B. Klein ◽  
Y. James Kang

To study possible mechanisms for metallothionein (MT) inhibition of ischemia-reperfusion-induced myocardial injury, cardiomyocytes isolated from MT-overexpressing transgenic neonatal mouse hearts and nontransgenic controls were subjected to 4 h of hypoxia (5% CO2-95% N2, glucose-free modified Tyrode's solution) followed by 1 h of reoxygenation in MEM + 20% fetal bovine serum (FBS) (5% CO2-95% air), and cytochrome c-mediated caspase-3 activation apoptotic pathway was determined. Hypoxia/reoxygenation-induced apoptosis was significantly suppressed in MT-overexpressing cardiomyocytes, as measured by both terminal deoxynucleotidyl transferase-mediated deoxyuridine 5-triphosphate nick-end labeling and annexin V-FITC binding. In association with apoptosis, mitochondrial cytochrome c release, as determined by Western blot, was observed to occur in nontransgenic cardiomyocytes. Correspondingly, caspase-3 was activated as determined by laser confocal microscopic examination with the use of FITC-conjugated antibody against active caspase-3 and by enzymatic assay. The activation of this apoptotic pathway was significantly inhibited in MT-overexpressing cells, as evidenced by both suppression of cytochrome c release and inhibition of caspase-3 activation. The results demonstrate that MT suppresses hypoxia/reoxygenation-induced cardiomyocyte apoptosis through, at least in part, inhibition of cytochrome c-mediated caspase-3 activation.


Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 4478-4478
Author(s):  
Julia Mazar ◽  
Alexandra Lichtenstein ◽  
Leora Katz ◽  
Ofer Shpilberg ◽  
Itai Levi ◽  
...  

Abstract Many types of antitumor therapy in general and AML in particular exert their effect by activating apoptosis. Apoptosis of AML cells can be induced by cytostatic drugs, corticosteroids, and radiation. Recently, the role of different proteases as possible targets for chemotherapy was described. N-tosyl-L-phenylalanine chloromethyl ketone (TPCK), a chymotrypsin-like protease (CLP) inhibitor was shown to exert a dual effect on leukemic cells: proapoptotic and antiapoptotic. In the present study the mechanism of its proapoptotic effect was addressed. It was found that the CLP inhibitors, TPCK and 3,4 dichloroisicoumarine induced apoptosis in a time- and concentration-dependent manner. Apoptosis was accompanied by a decrease in mitochondrial membrane potential, cytochrome c release, caspase-3 (but not caspase-8) activation, PS flip-flop (measured by Annexin-V staining followed by flow cytometry analysis) and chromatin condensation, but not fragmentation (detected by acridine orange/ethidium bromide staining). All apoptotic processes induced by TPCK were completely inhibited by cycloheximide. The ability of cycloheximide to inhibit TPCK-induced cell death suggests that protein synthesis plays a role in TPCK-induced apoptosis. Additionaly, the proapoptotic effect of TPCK was abolished by elimination of glucose from the medium. The data supports the role of mitochondria in this process. In the present study the apoptotic pathway driven by inhibition of CLP was demonstrated. Moreover, these findings suggest possible ways of preventing the proapoptotic activity of TPCK and thereby enhancimg its antiapoptotic action.


2003 ◽  
Vol 77 (1) ◽  
pp. 45-56 ◽  
Author(s):  
George A. Belov ◽  
Lyudmila I. Romanova ◽  
Elena A. Tolskaya ◽  
Marina S. Kolesnikova ◽  
Yuri A. Lazebnik ◽  
...  

ABSTRACT Cells respond to poliovirus infection by switching on the apoptotic program, implementation of which is usually suppressed by viral antiapoptotic functions. We show here that poliovirus infection of HeLa cells or derivatives of MCF-7 cells was accompanied by the efflux of cytochrome c from mitochondria. This efflux occurred during both abortive infection (e.g., interrupted by guanidine-HCl and ending with apoptosis) and productive infection (leading to cytopathic effect). The former type of infection, but not the latter, was accompanied by truncation of the proapoptotic protein Bid. The virus-triggered cytochrome c efflux was suppressed by overexpression of Bcl-2. Both abortive and productive infections also resulted in a decreased level of procaspase-9, as revealed by Western blotting. In the former case, this decrease was accompanied by the accumulation of a protein with the electrophoretic mobility of active caspase-9. In contrast, in the productively infected cells, the latter protein was absent but caspase-9-related polypeptides with altered mobility could be detected. Both caspase-9 and caspase-3 were shown to be essential for the development of such hallmarks of virus-induced apoptosis as chromatin condensation, DNA degradation, and nuclear fragmentation. These and some other results suggest the following scenario. Poliovirus infection activates the apoptotic pathway, involving mitochondrial damage, cytochrome c efflux, and consecutive activation of caspase-9 and caspase-3. The apoptotic signal appears to be amplified by a loop which includes secondary processing of Bid. The implementation of the apoptotic program in productively infected cells may be suppressed, however, by the viral antiapoptotic functions, which act at a step(s) downstream of the cytochrome c efflux. The suppression appears to be caused, at least in part, by aberrant processing and degradation of procaspase-9.


2019 ◽  
Vol 19 (4) ◽  
pp. 439-452 ◽  
Author(s):  
Mohamed R. Selim ◽  
Medhat A. Zahran ◽  
Amany Belal ◽  
Moustafa S. Abusaif ◽  
Said A. Shedid ◽  
...  

Objective: Conjugating quinolones with different bioactive pharmacophores to obtain potent anticancer active agents. Methods: Fused pyrazolopyrimidoquinolines 3a-d, Schiff bases 5, 6a-e, two hybridized systems: pyrazolochromenquinoline 7 and pyrazolothiazolidinquinoline 8, different substituted thiazoloquinolines 13-15 and thiazolo[3,2-a]pyridine derivatives 16a-c were synthesized. Their chemical structures were characterized through spectral and elemental analysis, cytotoxic activity on five cancer cell lines, caspase-3 activation, tubulin polymerization inhibition and cell cycle analysis were evaluated. Results: Four compounds 3b, 3d, 8 and 13 showed potent activity than doxorubicin on HCT116 and three compounds 3b, 3d and 8 on HEPG2. These promising derivatives showed increase in the level of caspase-3. The trifloromethylphenyl derivatives of pyrazolopyrimidoquinolines 3b and 3d showed considerable tubulin polymerization inhibitory activity. Both compounds arrested cell cycle at G2/M phase and induced apoptosis. Conclusion: Compounds 3b and 3d can be considered as promising anticancer active agents with 70% of colchicine activity on tubulin polymerization inhibition and represent hopeful leads that deserve further investigation and optimization.


Author(s):  
Amber M. Tavener ◽  
Megan C. Phelps ◽  
Richard L. Daniels

AbstractGlioblastoma (GBM) is a lethal astrocyte-derived tumor that is currently treated with a multi-modal approach of surgical resection, radiotherapy, and temozolomide-based chemotherapy. Alternatives to current therapies are urgently needed as its prognosis remains poor. Anthracyclines are a class of compounds that show great potential as GBM chemotherapeutic agents and are widely used to treat solid tumors outside the central nervous system. Here we investigate the cytotoxic effects of doxorubicin and other anthracyclines on GL261 glioma tumor cells in anticipation of novel anthracycline-based CNS therapies. Three methods were used to quantify dose-dependent effects of anthracyclines on adherent GL261 tumor cells, a murine cell-based model of GBM. MTT assays quantified anthracycline effects on cell viability, comet assays examined doxorubicin genotoxicity, and flow cytometry with Annexin V/PI staining characterized doxorubicin-induced apoptosis and necrosis. Dose-dependent reductions in GL261 cell viability were found in cells treated with doxorubicin (EC50 = 4.9 μM), epirubicin (EC50 = 5.9 μM), and idarubicin (EC50 = 4.4 μM). Comet assays showed DNA damage following doxorubicin treatments, peaking at concentrations of 1.0 μM and declining after 25 μM. Lastly, flow cytometric analysis of doxorubicin-treated cells showed dose-dependent induction of apoptosis (EC50 = 5.2 μM). Together, these results characterized the cytotoxic effects of anthracyclines on GL261 glioma cells. We found dose-dependent apoptotic induction; however at high concentrations we find that cell death is likely necrotic. Our results support the continued exploration of anthracyclines as compounds with significant potential for improved GBM treatments.


2017 ◽  
Vol 37 (7) ◽  
pp. 762-771 ◽  
Author(s):  
RB Khan ◽  
A Phulukdaree ◽  
AA Chuturgoon

The geographical distribution of oesophageal cancer is linked to the exposure of fumonisin B1 (FB1), a mycotoxin produced by fungi that contaminates staple food worldwide. Non-genotoxic carcinogens like FB1 disturb homeostasis through increased cell proliferation or suppression of apoptosis. This study investigated the involvement of FB1 (0–20 μM) in spindle-shaped N-cadherin (+) CD45 (−) osteoblastic (SNO) cell death. Cell viability and death were assessed using the MTS and Annexin V-Fluos assays, respectively. Caspase activities were determined luminometrically and the comet assay assessed DNA damage. Induction of oxoguanine glycosylase 1 (OGG1) was measured using quantitative Polymerase Chain Reaction (qPCR), while cleaved poly (ADP-ribose) polymerase 1 (PARP-1) and Bax were determined by western blotting. Cell viability and PARP-1 cleavage were not affected by 1.25 μM FB1, but phosphatidylserine externalization, Bax protein expression, caspase activity, comet tail length and OGG1 transcripts were increased. The reduced cell viability in 10 μM FB1-treated cells was accompanied by corresponding increases in externalized phosphatidylserine, Bax, caspase-3/7 activity and cleaved PARP-1. The OGG1 transcripts were not significantly increased, but comet tails were increased. Bax, caspase-3/7 activities and cleaved PARP-1 were inhibited at 20 μM FB1. In addition, the OGG1 transcript levels were decreased ( p < 0.0001) along with comet lengths ( p < 0.0001). This study showed that FB1-induced apoptosis in SNO cells may be caspase-dependent or caspase-independent; the pathway used depends on the exposure concentration.


2019 ◽  
Vol 39 (5) ◽  
Author(s):  
Dongxu Zhang ◽  
Houxian Liu ◽  
Binbin Yang ◽  
Jiasheng Hu ◽  
Yue Cheng

Abstract The present study aims to evaluate the anticancer effect of L-securinine on androgen-independent prostate cancer (AIPC) DU145 cells. L-securinine (2.5, 5, and 10 μM) treatment for 24, 48 and 72 h displayed strong growth inhibitory effect on DU145 cells in a concentration and time-dependent fashion but has less toxicity toward normal androgen-dependent LNCaP cells. Hoechst 332582 staining of DU145 cells and Annexin V-FITC/ PI dual-labeling followed by flow cytometry assay identified that this growth inhibition by L-securinine would be due to the induction of apoptosis. Moreover Transwell assay revealed that L-securinine significantly inhibited the cell migration/invasion ability of DU145 cells. Furthermore, results of western blotting showed that the involvement of mitochondrial apoptotic pathway in the L-securinine-induced apoptosis of DU145 cell, as evidenced by an increase in the protein expression of Bax, cleaved caspase-9, cleaved caspase-3, cytosolic cytochrome c, and cleaved PARP, together with a unchanged cleaved caspase-8 and decreased Bcl-2 protein expression. Also, L-securinine-induced antimetastatic activity in DU145 cells was associated with decreased protein expression of MMP-2 and MMP-9 and concurrent reduction of VEGF. In addition, further studies revealed that L-securinine may inhibit the protein expression of AGTR1, p-MEK1/2, p-ERK1/2, p-STAT3, PAX2, and p-PAX2, while the expression of ERK1/2, MEK1/2, and STAT3 protein retains intact. These findings suggest that L-securinine may be a promising chemopreventive agent against AIPC.


2007 ◽  
Vol 292 (1) ◽  
pp. G28-G38 ◽  
Author(s):  
Yanna Cao ◽  
Lu Chen ◽  
Weili Zhang ◽  
Yan Liu ◽  
Harry T. Papaconstantinou ◽  
...  

Transforming growth factor (TGF)-β-dependent apoptosis is important in the elimination of damaged or abnormal cells from normal tissues in vivo. Previously, we have shown that TGF-β inhibits the growth of rat intestinal epithelial (RIE)-1 cells. However, RIE-1 cells are relatively resistant to TGF-β-induced apoptosis due to a low endogenous Smad3-to-Akt ratio. Overexpression of Smad3 sensitizes RIE-1 cells (RIE-1/Smad3) to TGF-β-induced apoptosis by altering the Smad3-to-Akt ratio in favor of apoptosis. In this study, we utilized a genomic approach to identify potential downstream target genes that are regulated by TGF-β/Smad3. Total RNA samples were analyzed using Affymetrix oligonucleotide microarrays. We found that TGF-β regulated 518 probe sets corresponding to its target genes. Interestingly, among the known apoptotic genes included in the microarray analyses, only caspase-3 was induced, which was confirmed by real-time RT-PCR. Furthermore, TGF-β activated caspase-3 through protein cleavage. Upstream of caspase-3, TGF-β induced mitochondrial depolarization, cytochrome c release, and cleavage of caspase-9, which suggests that the intrinsic apoptotic pathway mediates TGF-β-induced apoptosis in RIE-1/Smad3 cells.


2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Prachya Janhom ◽  
Permphan Dharmasaroja

In vitrostudies have shown that extracts from mangosteen (Garcinia mangostanaLinn.) act as antioxidants and cytoprotective agents against oxidative damage. The protective effect of alpha-mangostin, the major xanthone found in the pericarp of the mangosteen, in cellular models of Parkinson’s disease (PD), has not been investigated. This study aims to investigate whether alpha-mangostin could protect SH-SY5Y neuroblastoma cells from MPP+-induced apoptosis. The effects of alpha-mangostin on MPP+-induced cell death were evaluated with a cell viability assay, staining for nuclear DNA morphology, flow cytometry for apoptotic cells and reactive oxygen species (ROS) production, quantitative real-time PCR for the expression of p53, Bax, and Bcl-2, and western blot analysis for cleaved caspase-3. Concomitant treatment with alpha-mangostin attenuated the effect of MPP+on cell viability and apoptotic cell death. Alpha-mangostin reduced ROS formation induced by MPP+. Bax/Bcl-2 expression ratio and expression of p53 were significantly lower in cells cocultured with alpha-mangostin and MPP+. The cotreated cells showed a significant decrease in activated caspase-3 compared with MPP+treatment alone. Our data suggest that cytoprotection of alpha-mangostin against MPP+-induced apoptosis may be associated with the reduction of ROS production, modulating the balance of pro- and antiapoptotic genes, and suppression of caspase-3 activation.


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