scholarly journals Botanical Alkyl Hydroquinone Derivative HQ17(3) Induces Calcium-Associated Mitochondrial Damage and Mitophagy to Exert Ctotoxicity to Philadelphila Chromosome(+) ALL Cells

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 5800-5800
Author(s):  
Yin-Chen Chou ◽  
Chia-Wei Chen ◽  
Yuan-Yeh Kuo ◽  
Liang-In Lin ◽  
Chung-Yi Hu
Keyword(s):  
Oxidative Stress ◽  
Cell Death ◽  
Membrane Potential ◽  
Er Stress ◽  
Mitochondrial Membrane Potential ◽  
Mitochondrial Membrane ◽  
Nuclear Translocation ◽  
Mitochondrial Superoxide ◽  
Apoptosis Inducing Factor ◽  
Mitotracker Green

Abstract Introduction: Acute lymphoblastic leukemias (ALLs) harboring t(9;22)(Ph+-ALL) are very high risk (VHR) ALL displaying poor clinical outcome irrespective of intensive chemotherapies plus tyrosine kinase inhibitor (TKI) treatment. HQ17(3)[10'(Z),13'(E),15'(E)-heptadecatrienyl hydroquinone] isolated from sap of the lacquer tree showed rapid (within 24hrs) and potent cytotoxic effect at micromolar concentration on several ALL cell lines, including Imatinib-refractory Ph+-ALL SUP-B15 cells, but spared normal PB leukocytes, and showed nontoxic in experimental rats after 28-day injection. Therefore HQ17(3) presents as a potential anti-leukemic agents and provide a platform for exploring anti-leukemic adjuvants. Our previous study showed HQ17(3)-induced rapid cell demise, characterized by oxidative stress, mitochondrial membrane potential disturbance, loss of membrane integrity, and nuclear DNA fragmentation. HQ17(3)-induced cell death is a caspase-independent program, and is different from the RIP1-mediated controlled necroptosis since both pan-caspase inhibitor and RIP-1 inhihitor failed to protect SUP-B15 cells from death. The ER stress markers (chaperon Grp78 and phosphorylated-eIF2α) were up-regulated as early as 5hrs after HQ17(3) treatment. Here we aim to illustrate the characters of the HQ17(3)-induced non-classical death on Ph+-SUP-B15 cells, focus on ER stress-associated mitochondrial Ca2+ homeostasis. Methods: Cell death and changes of mitochondria in response to HQ17(3) w/wo inhibitors were analyzed. Cells were stained by Annexin V/PI and analyzed by flow cytometry for cell death. Mitochondria mass, mitochondrial Ca2+ accumulation was detected by fluorescent Mitotracker Green and Rhod-2 probes, respectively. Mitochondrial superoxide was measured by Mitosox stain. Western blot analysis was used to analyze MFN1/2, OPA1 (mitochondrial markers). Nuclear accumulation of apoptosis inducing factor (AIF), co-localization of mitochondrial COX-IV and LC3-II (mitophagy) were revealed by immunofluorescence stain and confocal microscopy. Results: We showed mitochondrial Ca2+ accumulation at the early time when ER stress occurred (Fig 1), accompanied by mitochondrial superoxide elevation, followed by loss of mitochondrial membrane potential (MMP) and nuclear translocation of apoptosis-inducing factor (AIF). HQ17(3) treatment lead to decreased mitochondrial proteins MFN1/2 and OPA1, while Mitotracker Green stain showed significant loss of mitochondrial mass preceded cell death, indicating damaged mitochondria underwent fission followed by mitophagy. Immunofluorescence stain showed evidence of mitophagy (COX IV and LC3B co-localization). Calpain-1 inhibitor PD150606 blocked AIF nuclear translocation but only slightly reduced the HQ17(3)-induced cell death (Fig 2). Further, Ca2+ chelator Bapta-AM prevented mitochondrial superoxide production, MMP loss, mitophagy (Fig 3), and rescued cell death (Fig 1) more effectively. Conclusion: In Ph+-ALL SUP-B15 cells, HQ17(3) induce ER stress by yet-defined mechanism, this mobilizes Ca2+ to mitochondria and acts in multi-facet: a) results in AIF cleavage and translocation to mediate nuclear chromatin fragmentation, b) Ca2+-overload leads to oxidative stress and perturbs mitochondria integrity, c) damaged mitochondria trigger extensive mitophagy and cell death ensues. Therefore, agents that help elicit similar intricate effector network associated with ER/mitochondria stress will have potential to be adjuvants in aiding control of the Ph+ VHR-ALL cells refractory to conventional chemotherapies and TKI regime. Disclosures No relevant conflicts of interest to declare.

Abstract 371: Mitochondrial Antiviral Signaling (MAVS) Protects Cardiomyocytes Under Oxidative Stress by Interfering with Bax-Mediated Cell Death

2012 ◽  
Vol 111 (suppl_1) ◽  
Author(s):  
Toshitaka Yajima ◽  
Stanley Park ◽  
Hanbing Zhou ◽  
Michinari Nakamura ◽  
Mitsuyo Machida ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Cell Death ◽  
Membrane Potential ◽  
Cytochrome C ◽  
Mitochondrial Membrane Potential ◽  
Mitochondrial Membrane ◽  
Cytochrome C Release ◽  
Antiviral Signaling ◽  
Cell Death Pathway ◽  
The Impact

MAVS is a mitochondrial outer membrane protein that activates innate antiviral signaling by recognizing cytosolic viral RNAs and DNAs. While the discovery of MAVS is the first molecular evidence that links mitochondria to innate immune mechanisms, it is still unclear whether MAVS affects mitochondrial cell death as a member of caspase activation and recruitment domain (CARD)-containing proteins. We found that MAVS interacts with Bax through CARD by Yeast two-hybrid and a series of immunoprecipitation (IP) assay, which led us to hypothesize that MAVS functions not only in the innate antiviral mechanisms but also in the mitochondrial cell death pathway. Methods: 1) We examined molecular interaction between MAVS and Bax under oxidative stress by IP using isolated myocytes with H2O2 stimulation and the heart post ischemia-reperfusion (I/R). 2) We evaluated the effect of MAVS on mitochondrial membrane potential and apoptosis under H2O2 stimulation using isolated myocytes with adenoviral MAVS knockdown. 3) We investigated the impact of MAVS on %myocardial infarction (%MI) post I/R using cardiac-specific MAVS knockout (cKO) and transgenic (cTg) mice which we have originally generated. 4) We examined the effect of MAVS on recombinant Bax (rBax)-mediated cytochrome c release using isolated mitochondria from wild type (WT) and MAVS KO mice. Results: 1) The amount of Bax pulled down with MAVS was significantly increased in isolated myocytes with 0.2 mM H2O2 compared to those without stimulation (mean±SD; 1.808±0.14, n=5, p<0.001) and in the heart post I/R compared to sham (2.2±1.19, n=3, p=0.0081). 2) Myocytes with MAVS knockdown showed clear abnormalities in mitochondrial membrane potential and caspace-3 cleavage with 0.2 mM H2O2 compared to control cardiomyocytes. 3) MAVS cKO had significantly larger %MI than WT (81.9 ± 5.8% vs. 42.6 ± 13.6%, n=8, p=0.0008). In contrast, MAVS cTg had significantly smaller %MI that WT (30.0 ± 4.8% vs. 49.2 ± 4.8%, n=10, p=0.0113). 4) Mitochondria from MAVS KO exhibited cytochrome c release after incubation with 2.5 μ g of rBax while those from WT required 10 μ g of rBax. Conclusion: These results demonstrate that MAVS protects cardiomyocyte under oxidative stress by interfering with Bax-mediated cytochrome c release from mitochondria.

scholarly journals Vitamin K2 Modulates Organelle Damage and Tauopathy Induced by Streptozotocin and Menadione in SH-SY5Y Cells

Antioxidants ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 983
Author(s):  
Shruti Shandilya ◽  
Kavindra Kumar Kesari ◽  
Janne Ruokolainen
Keyword(s):  
Cell Death ◽  
Membrane Potential ◽  
Er Stress ◽  
Mitochondrial Membrane Potential ◽  
Tau Protein ◽  
Mitochondrial Membrane ◽  
Neuronal Cell Death ◽  
Neuronal Cell ◽  
Vitamin K2 ◽  
Total Tau

Vitamin K2, known for its antioxidative and anti-inflammatory properties, can act as a potent neuroprotective molecule. Despite its action against mitochondrial dysfunction, the mechanism underlying the links between the protective effects of vitamin K2 and endoplasmic reticulum (ER) stress along with basal levels of total tau protein and amyloid-beta 42 (Aβ42) has not been elucidated yet. To understand the neuroprotective effect of vitamin K2 during metabolic complications, SH-SY5Y cells were treated with streptozotocin for 24 h and menadione for 2 h in a dose-dependent manner, followed by post-treatment of vitamin K2 for 5 h. The modulating effects of vitamin K2 on cell viability, lactate dehydrogenase release, reactive oxygen species (ROS), mitochondrial membrane potential, ER stress marker (CHOP), an indicator of unfolded protein response (UPR), inositol requiring enzyme 1 (p-IRE1α), glycogen synthase kinase 3 (GSK3α/β), total tau and Aβ42 were studied. Results showed that vitamin K2 significantly reduces neuronal cell death by inhibiting cytotoxicity and ROS levels and helps in the retainment of mitochondrial membrane potential. Moreover, vitamin K2 significantly decreased the expression of CHOP protein along with the levels and the nuclear localization of p-IRE1 α, thus showing its significant role in inhibiting chronic ER stress-mediated UPR and eventually cell death. In addition, vitamin K2 significantly down-regulated the expression of GSK3 α/β together with the levels of total tau protein, with a petite effect on secreted Aβ42 levels. These results suggested that vitamin K2 alleviated mitochondrial damage, ER stress and tauopathy-mediated neuronal cell death, which highlights its role as new antioxidative therapeutics targeting related cellular processes.

scholarly journals Geranylgeranyl Acetone Prevents Glutamate-induced Cell Death in HT-22 Cells by Increasing Mitochondrial Membrane Potential

2020 ◽  
Author(s):  
Eriko Sugano ◽  
Yuka Endo ◽  
Akihisa Sugai ◽  
Yuki Kikuchi ◽  
Kitako Tabata ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Cell Death ◽  
Membrane Potential ◽  
Mitochondrial Membrane Potential ◽  
Mitochondrial Membrane ◽  
Oxygen Species ◽  
Mouse Hippocampus ◽  
Calcium Buffering ◽  
Shock Proteins

Geranylgeranyl acetone (GGA) protects against various types of cell damages by upregulating heat shock proteins. We investigated whether GGA protect neuronal cells from cell death induced by oxidative stress. Glutamate exposure was lethal to HT-22 cells which comprise a neuronal line derived from mouse hippocampus. This configuration is often used as a model for hippocampus neurodegeneration in vitro. In the present study, GGA protected HT-22 cells from glutamate-induced oxidative stress. GGA pretreatment did not induce Hsps. Moreover, reactive oxygen species increased to the same extent in both GGA-pretreated and untreated cells exposed to glutamate. In contrast, glutamate exposure and GGA pretreatment increased mitochondrial membrane potential. However, increases in intracellular Ca2+ concentration were inhibited by GGA pretreatment. In addition, the increase of phosphorylated ERKs by the glutamate exposure was inhibited by GGA pretreatment. These findings suggest that GGA protects HT-22 cells from glutamate-provoked cell death without Hsp induction and that the mitochondrial calcium buffering capacity plays an important role in this protective effect.

Alterations in zinc homeostasis underlie endothelial cell death induced by oxidative stress from acute exposure to hydrogen peroxide

2007 ◽  
Vol 292 (1) ◽  
pp. L165-L177 ◽  
Author(s):  
Dean A. Wiseman ◽  
Sandra M. Wells ◽  
Maryann Hubbard ◽  
Jonathan E. Welker ◽  
Stephen M. Black
Keyword(s):  
Oxidative Stress ◽  
Cell Death ◽  
Membrane Potential ◽  
Endothelial Cell ◽  
Mitochondrial Membrane Potential ◽  
Mitochondrial Membrane ◽  
Binding Protein ◽  
Zinc Homeostasis ◽  
Acute Exposure ◽  
Disease States

Oxidative stress has been associated with multiple pathologies and disease states, including those involving the cardiovascular system. Previously, we showed that pulmonary artery endothelial cells (PAECs) undergo apoptosis after acute exposure to H2O2. However, the underlying mechanisms regulating this process remain unclear. Because of the prevalence of H2O2 in normal physiological processes and apparent loss of regulation in disease states, the purpose of this study was to develop a more complete understanding of H2O2-mediated adverse effects on endothelial cell survival. Acute exposure of PAECs to H2O2 caused a dose-dependent increase in cellular release of lactate dehydrogenase and a significant increase in production of superoxide ions, which appear to be generated within the mitochondria, as well as a significant loss of mitochondrial membrane potential and activity. Subsequent to the loss of mitochondrial membrane potential, PAECs exhibited significant caspase activation and apoptotic nuclei. We also observed a significant increase in intracellular free Zn2+ after bolus exposure to H2O2. To determine whether this increase in Zn2+ was involved in the apoptotic pathway induced by acute H2O2 exposure, we developed an adenoviral construct for overexpression of the Zn2+-binding protein metallothionein-1. Our data indicate that chelating Zn2+, either pharmacologically with N,N,N′, N-tetrakis(2-pyridylmethyl)ethylene diamine or by overexpression of the Zn2+-binding protein metallothionein-1, in PAECs conferred significant protection from induction of apoptosis and cell death associated with the effects of acute H2O2 exposure. Our results show that the acute toxicity profile of H2O2 can be attributed, at least in part, to liberation of Zn2+ within PAECs. We speculate that regulation of Zn2+ levels may represent a potential therapeutic target for cardiovascular disease associated with acute oxidative stress.

scholarly journals Relationship between ROS production, MnSOD activation and periods of fasting and re-feeding in freshwater shrimp Neocaridina davidi (Crustacea, Malacostraca)

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e7399 ◽  
Author(s):  
Agnieszka Włodarczyk ◽  
Grażyna Wilczek ◽  
Piotr Wilczek ◽  
Sebastian Student ◽  
Anna Ostróżka ◽  
...  
Keyword(s):  
Cell Death ◽  
Membrane Potential ◽  
Mitochondrial Membrane Potential ◽  
Mitochondrial Membrane ◽  
Freshwater Shrimp ◽  
Mitochondrial Superoxide ◽  
Freshwater Shrimps ◽  
F Cells ◽  
D Cells ◽  
Storage Cells

The middle region of the digestive system, the midgut of freshwater shrimp Neocaridina davidi is composed of a tube-shaped intestine and the hepatopancreas formed by numerous caeca. Two types of cells have been distinguished in the intestine, the digestive cells (D-cells) and regenerative cells (R-cells). The hepatopancreatic tubules have three distinct zones distinguished along the length of each tubule—the distal zone with R-cells, the medial zone with differentiating cells, and the proximal zone with F-cells (fibrillar cells) and B-cells (storage cells). Fasting causes activation of cell death, a reduction in the amount of reserve material, and changes in the mitochondrial membrane potential. However, here we present how the concentration of ROS changes according to different periods of fasting and whether re-feeding causes their decrease. In addition, the activation/deactivation of mitochondrial superoxide dismutase (MnSOD) was analyzed. The freshwater shrimps Neocaridina davidi (Crustacea, Malacostraca, Decapoda) were divided into experimental groups: animals starved for 14 days, animals re-fed for 4, 7, and 14 days. The material was examined using the confocal microscope and the flow cytometry. Our studies have shown that long-term starvation increases the concentration of free radicals and MnSOD concentration in the intestine and hepatopancreas, while return to feeding causes their decrease in both organs examined. Therefore, we concluded that a distinct relationship between MnSOD concentration, ROS activation, cell death activation and changes in the mitochondrial membrane potential occurred.

Abstract 4362: Antibodies against KChIP2 Induce Ionic Imbalance and Cell Death in Isolated Rat Cardiomyocytes

Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Sangita Choudhury ◽  
Michael Schnell ◽  
Jan Lüdemann ◽  
Alexander Staudt ◽  
Heyo K Kroemer ◽  
...  
Keyword(s):  
Cell Death ◽  
Membrane Potential ◽  
Dilated Cardiomyopathy ◽  
Mitochondrial Membrane Potential ◽  
Mitochondrial Membrane ◽  
Caspase 3 ◽  
Nuclear Translocation ◽  
Rat Cardiomyocytes ◽  
Ionic Imbalance ◽  
Isolated Rat

Disturbances of humoral immunity have been described in patients with dilated cardiomyopathy (DCM). Antibodies against Kv channel-interacting proteins (KChIPs) may be associated with heart failure. Isolated rat cardiomyocytes were treated with antibodies against rat KChIP2 (80 pmol/ml) up to 24 hours. RNA and proteins were isolated after two hours by standard procedures and mRNA (TaqMan®) and protein (Western blot) expression was quantified. Translocations of NF-κB subunits p50, p65, c-Rel, and Rel-B were measured in nuclear protein extracts by ELISA after 60 minutes. Mitochondrial membrane potential ΔΨm and caspase-3 and -9 activities were determined by flow cytometry. Necrotic and apoptotic cells were distinguished by staining with Hoechst 33258 and propidium iodide. Total Ca 2+ and K + concentrations were quantified by a colorimetric assay and atomic absorption spectrometry, respectively, and normalized to the protein content of the cells. Antibodies against KChIP2 induced nuclear translocation of all NF-κB subunits analyzed. Pre-incubation with a blocking peptide or an NF-κB inhibitor, CAPE, prevented nuclear translocation. Anti-KChIP2-treatment for two hours significantly reduced KChIP2 mRNA (55±10%; n=4) and protein (73 ±5%, n =4) expression compared to cells treated with experimental buffer (100%). Treatment for 24 hours did not induce changes in mitochondrial membrane potential, ΔΨm. Caspase-3 and -9 activities were not altered as well. The anti-KChIP2-treated cell population consisted of 75±3% necrotic, 2±1% apoptotic, and 13±2% viable cells. In contrast, cells treated with experimental buffer were viable to 86±1%. After five minutes, anti-KChIP2 induced significant increases in total intracellular Ca 2+ (plus 11±2%) and K + (plus 18±2%) concentrations. These antibody-mediated effects were prevented in the presence of a blocking peptide. Antibodies against KChIP2 induce ionic imbalance, activate the transcription factor NF-κB, down-regulate KChIP2 expression and enhance cell death rate probably due to necrosis. Antibodies against KChIP2 may contribute to the development and progression of dilated cardiomyopathy.

scholarly journals Genomic instability induced by radiation-mimicking chemicals is not associated with persistent mitochondrial degeneration

2021 ◽  
Author(s):  
Luukkonen Jukka ◽  
Höytö Anne ◽  
Sokka Miiko ◽  
Syväoja Juhani ◽  
Juutilainen Jukka ◽  
...  
Keyword(s):  
Membrane Potential ◽  
Ionizing Radiation ◽  
Genomic Instability ◽  
Mitochondrial Membrane Potential ◽  
Mitochondrial Function ◽  
Mitochondrial Membrane ◽  
Neuroblastoma Cells ◽  
Superoxide Production ◽  
Mitochondrial Activity ◽  
Mitochondrial Superoxide

AbstractIonizing radiation has been shown to cause induced genomic instability (IGI), which is defined as a persistently increased rate of genomic damage in the progeny of the exposed cells. In this study, IGI was investigated by exposing human SH-SY5Y neuroblastoma cells to hydroxyurea and zeocin, two chemicals mimicking different DNA-damaging effects of ionizing radiation. The aim was to explore whether IGI was associated with persistent mitochondrial dysfunction. Changes to mitochondrial function were assessed by analyzing mitochondrial superoxide production, mitochondrial membrane potential, and mitochondrial activity. The formation of micronuclei was used to determine immediate genetic damage and IGI. Measurements were performed either immediately, 8 days, or 15 days following exposure. Both hydroxyurea and zeocin increased mitochondrial superoxide production and affected mitochondrial activity immediately after exposure, and mitochondrial membrane potential was affected by zeocin, but no persistent changes in mitochondrial function were observed. IGI became manifested 15 days after exposure in hydroxyurea-exposed cells. In conclusion, immediate responses in mitochondrial function did not cause persistent dysfunction of mitochondria, and this dysfunction was not required for IGI in human neuroblastoma cells.

scholarly journals Artemisinin attenuated oxidative stress and apoptosis by inhibiting autophagy in MPP+-treated SH-SY5Y cells

2021 ◽  
Vol 28 (1) ◽  
Author(s):  
Junqiang Yan ◽  
Hongxia Ma ◽  
Xiaoyi Lai ◽  
Jiannan Wu ◽  
Anran Liu ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Membrane Potential ◽  
Protein Expression ◽  
Mitochondrial Membrane Potential ◽  
Western Blotting ◽  
Cell Apoptosis ◽  
Mitochondrial Membrane ◽  
Caspase 3 ◽  
Neuroprotective Effect ◽  
Neuroprotective Effects

Abstract Background Parkinson’s disease (PD) is the second most common neurodegenerative disease after Alzheimer's disease. The oxidative stress is an important component of the pathogenesis of PD. Artemisinin (ART) has antioxidant and neuroprotective effects. The purpose of this study is to explore the neuroprotective effect of ART on 1-methyl-4-phenyliodine iodide (MPP +)-treated SH-SY5Y cells and underlying mechanism. Methods We used MPP+-treated SH-SY5Y cells to study the neuroprotective effect of ART. Cell viability was measured by MTT assay after incubating the cells with MPP+ and/or ART for 24 h. DCFH-DA was used to detect the level of intracellular reactive oxygen species (ROS), and WST-8 was used to detect the level of superoxide dismutase (SOD). The level of intracellular reduced glutathione (GSH) was detected with 5,5΄-dithiobis-(2-nitrobenzoic acid), and the level of malondialdehyde (MDA) was assessed based on the reaction of MDA and thiobarbituric acid. A mitochondrial membrane potential detection kit (JC-1) was used to detect changes in the mitochondrial membrane potential (MMP), and an Annexin V-FITC cell apoptosis kit was used to detect cell apoptosis. The expression levels of caspase-3, cleaved caspase-3 and the autophagy-related proteins LC3, beclin-1, and p62 were detected by Western blotting. In addition, to verify the change in autophagy, we used immunofluorescence to detect the expression of LC3 and p62. Results No significant cytotoxicity was observed at ART concentrations up to 40 μM. ART could significantly increase the viability of SH-SY5Y cells treated with MPP+ and reduce oxidative stress damage and apoptosis. In addition, the Western blotting and immunofluorescence results showed that MPP+ treatment could increase the protein expression of beclin1 and LC3II/LC3I and decrease the protein expression of p62, indicating that MPP+ treatment could induce autophagy. Simultaneous treatment with ART and MPP+ could decrease the protein expression of beclin1 and LC3II/LC3I and increase the protein expression of p62, indicating that ART could decrease the level of autophagy induced by MPP+. Conclusion Our results indicate that ART has a protective effect on MPP+-treated SH-SY5Y cells by the antioxidant, antiapoptotic activities and inhibition of autophagy. Our findings may provide new hope for the prevention and treatment of PD.

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