N-terminal cleavage of Bax by calpain generates a potent proapoptotic 18-kDa fragment that promotes Bcl-2-independent cytochrome C release and apoptotic cell death

Objective: The main aim of the study was to investigate the bioactive compound vanillin extracted from proso millet (compound 1), and barnyard millet (compound 2) induces apoptotic cell death and whether it is mediated through mitochondrial pathway in HT-29 and MCF-7 cell line.Methods: The cells were treated with 250 μg/ml and 1000 μg/ml concentration of extracted vanillin for 48 hrs. Cytochrome c release and expression level of pro-apoptotic protein Bax and caspase-9 were detected by western blot analysis.Results: The results reveal that extracted compounds increased the release of cytochrome c and upregulating the expression of Bax and caspase-9 as concentration increases in a dose-dependent manner.Conclusion: The study suggests that the vanillin compound extracted from these millets induces apoptotic cell death through a mitochondria-dependent pathway.

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Abstract 5520: A novel HDAC inhibitor, N-hydroxy-7-(2-naphthylthio) heptanomide (HNHA), induces apoptotic cell death through mitochondrial cytochrome c release in renal cell carcinoma

10.1158/1538-7445.am2014-5520 ◽

2014 ◽

Author(s):

Kyung Seok Han ◽

Ki Cheong Park ◽

Jeong Yong Jeon ◽

Sang Yong Kim ◽

Dami Song ◽

...

Keyword(s):

Renal Cell Carcinoma ◽

Cell Death ◽

Cytochrome C ◽

Cell Carcinoma ◽

Hdac Inhibitor ◽

Renal Cell ◽

Apoptotic Cell ◽

Apoptotic Cell Death ◽

Mitochondrial Cytochrome ◽

Cytochrome C Release

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UQCRC1 Engages Cytochrome C for Neuronal Apoptotic Cell Death

SSRN Electronic Journal ◽

10.2139/ssrn.3748744 ◽

2020 ◽

Author(s):

Yu-Chien Hung ◽

Kuan-Lin Huang ◽

Po-Lin Chen ◽

Han-Yi Lin ◽

Huei-An Lu ◽

...

Keyword(s):

Cell Death ◽

Cytochrome C ◽

Apoptotic Cell ◽

Apoptotic Cell Death

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Quinacrine-Induced Autophagy in Ovarian Cancer Triggers Cathepsin-L Mediated Lysosomal/Mitochondrial Membrane Permeabilization and Cell Death

Cancers ◽

10.3390/cancers13092004 ◽

2021 ◽

Vol 13 (9) ◽

pp. 2004

Author(s):

Prabhu Thirusangu ◽

Christopher L. Pathoulas ◽

Upasana Ray ◽

Yinan Xiao ◽

Julie Staub ◽

...

Keyword(s):

Ovarian Cancer ◽

Cell Death ◽

Cytochrome C ◽

Cancer Cells ◽

Apoptotic Cell ◽

Cathepsin L ◽

Membrane Permeabilization ◽

Apoptotic Cell Death ◽

Ovarian Cancer Cells ◽

Autophagic Flux

We previously reported that the antimalarial compound quinacrine (QC) induces autophagy in ovarian cancer cells. In the current study, we uncovered that QC significantly upregulates cathepsin L (CTSL) but not cathepsin B and D levels, implicating the specific role of CTSL in promoting QC-induced autophagic flux and apoptotic cell death in OC cells. Using a Magic Red® cathepsin L activity assay and LysoTracker red, we discerned that QC-induced CTSL activation promotes lysosomal membrane permeability (LMP) resulting in the release of active CTSL into the cytosol to promote apoptotic cell death. We found that QC-induced LMP and CTSL activation promotes Bid cleavage, mitochondrial outer membrane permeabilization (MOMP), and mitochondrial cytochrome-c release. Genetic (shRNA) and pharmacological (Z-FY(tBU)-DMK) inhibition of CTSL markedly reduces QC-induced autophagy, LMP, MOMP, apoptosis, and cell death; whereas induced overexpression of CTSL in ovarian cancer cell lines has an opposite effect. Using recombinant CTSL, we identified p62/SQSTM1 as a novel substrate of CTSL, suggesting that CTSL promotes QC-induced autophagic flux. CTSL activation is specific to QC-induced autophagy since no CTSL activation is seen in ATG5 knockout cells or with the anti-malarial autophagy-inhibiting drug chloroquine. Importantly, we showed that upregulation of CTSL in QC-treated HeyA8MDR xenografts corresponds with attenuation of p62, upregulation of LC3BII, cytochrome-c, tBid, cleaved PARP, and caspase3. Taken together, the data suggest that QC-induced autophagy and CTSL upregulation promote a positive feedback loop leading to excessive autophagic flux, LMP, and MOMP to promote QC-induced cell death in ovarian cancer cells.

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Calcineurin-mediated Bad translocation regulates cyanide-induced neuronal apoptosis

Biochemical Journal ◽

10.1042/bj20031107 ◽

2004 ◽

Vol 379 (3) ◽

pp. 805-813 ◽

Cited By ~ 25

Author(s):

Yan SHOU ◽

Li LI ◽

Krishnan PRABHAKARAN ◽

Joseph L. BOROWITZ ◽

Gary E. ISOM

Keyword(s):

Cell Death ◽

Cytochrome C ◽

Cyclosporin A ◽

Apoptotic Cell ◽

Calcineurin Inhibitors ◽

Apoptotic Response ◽

Cytochrome C Release ◽

Cortical Cells ◽

Subsequent Activation ◽

Induced Apoptosis

In cyanide-induced apoptosis, an increase in cytosolic free Ca2+ and generation of reactive oxygen species are initiation stimuli for apoptotic cell death. Previous studies have shown that cyanide-stimulated translocation of Bax (Bcl-associated X protein) to mitochondria is linked with release of cytochrome c and subsequent activation of a caspase cascade [Shou, Li, Prabhakaran, Borowitz and Isom (2003) Toxicol. Sci. 75, 99–107]. In the present study, the relationship of the cyanide-induced increase in cytosolic free Ca2+ to activation of Bad (Bcl-2/Bcl-XL-antagonist, causing cell death) was determined in cortical cells. Bad is a Ca2+-sensitive pro-apoptotic Bcl-2 protein, which on activation translocates from cytosol to mitochondria to initiate cytochrome c release. In cultured primary cortical cells, cyanide produced a concentration- and time-dependent translocation of Bad from cytosol to mitochondria. Translocation occurred early in the apoptotic response, since mitochondrial Bad was detected within 1 h of cyanide treatment. Mitochondrial levels of the protein continued to increase up to 12 h post-cyanide exposure. Concurrent with Bad translocation, a Ca2+-sensitive increase in cellular calcineurin activity was observed. Increased cytosolic Ca2+ and calcineurin activation stimulated Bad translocation since BAPTA [bis-(o-aminophenoxy)ethane-N,N,N´,N´-tetra-acetic acid], an intracellular Ca2+ chelator, and cyclosporin A, a calcineurin inhibitor, significantly reduced translocation. BAPTA also blocked release of cytochrome c from mitochondria as well as apoptosis. Furthermore, treatment of cells with the calcineurin inhibitors cyclosporin A or FK506 blocked the apoptotic response, linking calcineurin activation and the subsequent translocation of Bad to cell death. These observations show that by inducing a rapid increase in cytosolic free Ca2+, cyanide can partially initiate the apoptotic cascade through a calcineurin-mediated translocation of Bad to mitochondria.

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Alternating metabolic pathways in NGF-deprived sympathetic neurons affect caspase-independent death

The Journal of Cell Biology ◽

10.1083/jcb.200302109 ◽

2003 ◽

Vol 162 (2) ◽

pp. 245-256 ◽

Cited By ~ 23

Author(s):

Louis K. Chang ◽

Robert E. Schmidt ◽

Eugene M. Johnson

Keyword(s):

Cell Death ◽

Cytochrome C ◽

Apoptotic Cell ◽

Sympathetic Neurons ◽

Permeability Transition Pore ◽

Permeability Transition ◽

Minor Role ◽

Caspase Inhibitor ◽

Cytochrome C Release ◽

Independent Manner

Mitochondrial release of cytochrome c in apoptotic cells activates caspases, which execute apoptotic cell death. However, the events themselves that culminate in caspase activation can have deleterious effects because caspase inhibitor–saved cells ultimately die in a caspase-independent manner. To determine what events may underlie this form of cell death, we examined bioenergetic changes in sympathetic neurons deprived of NGF in the presence of a broad-spectrum caspase inhibitor, boc-aspartyl-(OMe)-fluoromethylketone. Here, we report that NGF-deprived, boc-aspartyl-(OMe)-fluoromethylketone–saved neurons rely heavily on glycolysis for ATP generation and for survival. Second, the activity of F0F1 contributes to caspase-independent death, but has only a minor role in the maintenance of mitochondrial membrane potential, which is maintained primarily by electron transport. Third, permeability transition pore inhibition by cyclosporin A attenuates NGF deprivation–induced loss of mitochondrial proteins, suggesting that permeability transition pore opening may have a function in regulating the degradation of mitochondria after cytochrome c release. Identification of changes in caspase inhibitor–saved cells may provide the basis for rational strategies to augment the effectiveness of the therapeutic use of postmitochondrial interventions.

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Neuroprotective Effect of Tricyclic Pyridine Alkaloids from Fusarium lateritium SSF2, against Glutamate-Induced Oxidative Stress and Apoptosis in the HT22 Hippocampal Neuronal Cell Line

Antioxidants ◽

10.3390/antiox9111115 ◽

2020 ◽

Vol 9 (11) ◽

pp. 1115

Author(s):

Dahae Lee ◽

Hyun Gyu Choi ◽

Ji Hye Hwang ◽

Sang Hee Shim ◽

Ki Sung Kang

Keyword(s):

Cell Death ◽

Membrane Potential ◽

Mitochondrial Membrane Potential ◽

Mitochondrial Membrane ◽

Apoptotic Cell ◽

Apoptotic Cell Death ◽

Cytochrome C Release ◽

Ht22 Cells ◽

Superoxide Anion Production ◽

Fusarium Lateritium

Excessive glutamate damages neuronal cells via the accumulation of intracellular reactive oxygen species (ROS), calcium ion (Ca2+) influx, depolarization of mitochondrial membrane potential, and apoptosis, which may result in the development of chronic neurodegenerative diseases. In this study, we evaluated the effects of 4,6′-anhydrooxysporidinone isolated from endophytic fungus Fusarium lateritium SSF2 on glutamate-induced cytotoxicity, accumulation of intracellular ROS, increases in superoxide anion production, Ca2+, depolarization of mitochondrial membrane potential, and apoptotic cell death in hippocampal HT22 cells. 2′,7′-Dichlorofluorescin diacetate (H2DCFDA) staining was used to determine the intracellular reactive oxygen species concentration and dihydroethidine (DHE) staining was used to determine the superoxide radical. Expression of the nuclear factor-erythroid-2–related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) was analyzed by Western blot. Fluo-4 staining was used to determine the intracellular Ca2+ levels. In order to explore mitochondrial membrane potential, tetramethylrhodamine methyl ester (TMRM) staining was used. Apoptotic cell death was evaluated using Annexin-V/propidium iodide (PI) staining and TUNEL staining. Expression of the cytochrome c release and cleaved caspase-9, -3 was analyzed by Western blot. Here, we were able to isolate 4,6′-anhydrooxysporidinone from endophytic fungus, Fusarium lateritium SSF2, which was shown to protect HT22 cells from glutamate-induced cytotoxicity, accumulation of intracellular ROS, increases in superoxide anion production, Ca2+, and depolarization of mitochondrial membrane potential. In addition, 4,6′-anhydrooxysporidinone enhanced the expressions of Nrf2 and HO-1. It also inhibited the apoptotic cell death through the inhibition of cytochrome c release and cleaved caspase-9, -3 in glutamate-treated HT22 cells. Therefore, our results provide ample evidence of the neuroprotective properties of 4,6′-anhydrooxysporidinone.

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Greensporone A, a Fungal Secondary Metabolite Suppressed Constitutively Activated AKT via ROS Generation and Induced Apoptosis in Leukemic Cell Lines

Biomolecules ◽

10.3390/biom9040126 ◽

2019 ◽

Vol 9 (4) ◽

pp. 126 ◽

Cited By ~ 1

Author(s):

Kirti Prabhu ◽

Kodappully Siveen ◽

Shilpa Kuttikrishnan ◽

Anh Jochebeth ◽

Tayyiba Ali ◽

...

Keyword(s):

Cell Death ◽

Cytochrome C ◽

Cell Lines ◽

Apoptotic Cell ◽

Leukemic Cell ◽

Apoptotic Cell Death ◽

Leukemic Cells ◽

Leukemic Cell Lines ◽

Fungal Secondary Metabolite

Greensporone A is a fungal secondary metabolite that has exhibited potential in vitro for anti-proliferative activity in vitro. We studied the anticancer activity of greensporone A in a panel of leukemic cell lines. Greensporone A-mediated inhibition of proliferation is found to be associated with the induction of apoptotic cell death. Greensporone A treatment of leukemic cells causes inactivation of constitutively activated AKT and its downstream targets, including members GSK3 and FOXO1, and causes downregulation of antiapoptotic genes such as Inhibitor of Apoptosis (IAPs) and Bcl-2. Furthermore, Bax, a proapoptotic member of the Bcl-2 family, was found to be upregulated in leukemic cell lines treated with greensporone A. Interestingly, gene silencing of AKT using AKT specific siRNA suppressed the expression of Bcl-2 with enhanced expression of Bax. Greensporone A-mediated increase in Bax/Bcl-2 ratio causes permeabilization of the mitochondrial membrane leading to the accumulation of cytochrome c in the cytoplasm. Greensporone A-induced cytochrome c accumulation causes the activation of caspase cascade and cleavage of its effector, poly(ADP-ribose) polymerase (PARP), leading to apoptosis. Greensporone A-mediated apoptosis in leukemic cells occurs through the generation of reactive oxygen species (ROS) due to depletion of glutathione (GSH) levels. Finally, greensporone A potentiated the anticancer activity of imatinib in leukemic cells. In summary, our study showed that greensporone A suppressed the growth of leukemic cells via induction of apoptotic cell death. The apoptotic cell death occurs by inhibition of AKT signaling and activation of the intrinsic apoptotic/caspase pathways. These results raise the possibility that greensporone A could be developed as a therapeutic agent for the treatment of leukemia and other hematological malignancies.

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