Wogonin reduces cardiomyocyte apoptosis from mitochondrial release of cytochrome c to improve doxorubicin‑induced cardiotoxicity

Abstract Background Tumor necrosis factor receptor-associated protein 1 (TRAP1) plays a protective effect in hypoxic cardiomyocytes, but the precise mechanisms are not well clarified. The study is aimed to identify the mechanism of TRAP1 on hypoxic damage in cardiomyocytes. Methods In this study, the effects of TRAP1 and cytochrome c oxidase subunit II (COXII) on apoptosis in hypoxia-induced cardiomyocytes were explored using overexpression and knockdown methods separately. Results Hypoxia induced cardiomyocyte apoptosis, and TRAP1 overexpression notably inhibited apoptosis induced by hypoxia. Conversely, TRAP1 silencing promoted apoptosis in hypoxic cardiomyocytes. Further investigation revealed that the proapoptotic effects caused by the silencing of TRAP1 were prevented by COXII overexpression, whereas COXII knockdown reduced the antiapoptotic function induced by TRAP1 overexpression. Additionally, changes in the release of cytochrome c from mitochondria into the cytosol and the caspase-3 activity in the cytoplasm, as well as reactive oxygen species production, were found to be correlated with the changes in apoptosis. Conclusions The current study uncovered that TRAP1 regulates hypoxia-induced cardiomyocyte apoptosis through a mitochondria-dependent apoptotic pathway mediated by COXII, in which reactive oxygen species presents as an important component.

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Prostaglandin E1 Attenuates Post-Cardiac Arrest Myocardial Dysfunction via Inhibiting Mitochondria-Mediated Cardiomyocyte Apoptosis

10.21203/rs.3.rs-21943/v1 ◽

2020 ◽

Author(s):

Chenglei Su ◽

Xinhui Fan ◽

Feng Xu ◽

Jiali Wang ◽

Yuguo Chen

Keyword(s):

Cardiac Arrest ◽

Cytochrome C ◽

Rat Model ◽

Prostaglandin E1 ◽

Caspase 3 ◽

Myocardial Dysfunction ◽

Cardiomyocyte Apoptosis ◽

H9c2 Cells ◽

Protein Levels ◽

Mptp Opening

Abstract Background: Post-cardiac arrest myocardial dysfunction (PAMD) is a leading cause of death in resuscitated patients after cardiac arrest (CA). Prostaglandin E1 (PGE1) is a clinical drug used to mitigate ischemia injury. However, its effect on PAMD remains unknown. Methods: We investigated the protective effects of PGE1 on PAMD in a rat model of cardiac arrest and a hypoxia-reoxygenation (H/R) H9c2 cell model. Forty-two male Wistar rats were randomly assigned to CA, CA+PGE1, and sham groups. Asphyxia for 8 min followed by cardiopulmonary resuscitation was performed in the CA and CA+PGE1 groups. PGE1 (1 μg/kg) was intravenously administered at the onset of return of spontaneous circulation (ROSC). Ejection fraction (EF) and cardiac output (CO) were measured at baseline, 1, 2, 3, and 4 h after ROSC; survival was monitored for 72 h. Cardiomyocyte apoptosis, mitochondrial permeability transition pore (mPTP) opening, and protein levels of glycogen synthase kinase 3β (GSK3β), cytochrome c, and cleaved caspase-3 were measured 4 h after ROSC. H9c2 cells were treated with PGE1(0.5 μM) at the start of reoxygenation. Apoptosis, mPTP opening, and protein levels of GSK3β, cytochrome c, and cleaved caspase-3 of H9c2 cells were detected. Results: Compared to the CA group, PGE1 treatment significantly increased the EF and CO within 4 h after ROSC and improved the survival rate. It activated GSK3β, prevented mPTP opening, suppressed cytochrome c and cleaved caspase-3 expression, and reduced cardiomyocyte apoptosis in the rat model. In vitro, Changes in GSK3β, mPTP opening, cytochrome c and cleaved caspase-3 expression, and apoptosis in H9c2 cells were consistent with those in the rat model. Conclusions: Our results indicate that PGE1 attenuates PAMD via inhibiting mitochondria-mediated cardiomyocyte apoptosis.

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GW25-e3224 Omi/HtrA2 Cause Cardiomyocyte Apoptosis via Release of Cytochrome C in Aging Rats

Journal of the American College of Cardiology ◽

10.1016/j.jacc.2014.06.108 ◽

2014 ◽

Vol 64 (16) ◽

pp. C22

Author(s):

Liu Xin ◽

Wang Ke ◽

Liu Huirong

Keyword(s):

Cytochrome C ◽

Cardiomyocyte Apoptosis ◽

Aging Rats

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IL-22 ameliorated cardiomyocyte apoptosis in cardiac ischemia/reperfusion injury by blocking mitochondrial membrane potential decrease, inhibiting ROS and cytochrome C

Biochimica et Biophysica Acta (BBA) - Molecular Basis of Disease ◽

10.1016/j.bbadis.2021.166171 ◽

2021 ◽

pp. 166171

Author(s):

Yang Che ◽

Yu Tian ◽

Rong Chen ◽

Lin Xia ◽

Fang Liu ◽

...

Keyword(s):

Membrane Potential ◽

Cytochrome C ◽

Reperfusion Injury ◽

Mitochondrial Membrane Potential ◽

Mitochondrial Membrane ◽

Ischemia Reperfusion Injury ◽

Ischemia Reperfusion ◽

Cardiac Ischemia ◽

Cardiomyocyte Apoptosis

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miRNA-19b-3p Stimulates Cardiomyocyte Apoptosis Induced by Myocardial Ischemia Reperfusion via Downregulating PTEN

Disease Markers ◽

10.1155/2021/9956666 ◽

2021 ◽

Vol 2021 ◽

pp. 1-7

Author(s):

Ke Li ◽

Xujie Ya ◽

Xiujuan Duan ◽

Yang Li ◽

Xuefeng Lin

Keyword(s):

Cytochrome C ◽

Myocardial Ischemia ◽

Ischemia Reperfusion ◽

Malonic Dialdehyde ◽

B Cell Lymphoma ◽

Cardiomyocyte Apoptosis ◽

Luciferase Reporter ◽

Gene Expressions ◽

Gene Assay ◽

Myocardial Ischemia Reperfusion

Objective. To clarify the function of miRNA-19b-3p in accelerating myocardial ischemia-reperfusion injury- (MIRI-) induced cardiomyocyte apoptosis by downregulating gene of phosphate and tension homology deleted on chromsome ten (PTEN), thus influencing the progression of acute myocardial infarction. Materials and Methods. miRNA-19b-3p and PTEN levels in HCM cells undergoing hypoxia/reoxygenation (H/R) were determined. Meanwhile, activities of myocardium injury markers [lactate dehydrogenase (LDH), malondialdehyde; malonic dialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GSH-PX)] in H/R-induced HCM cells were tested. Through dual-luciferase reporter gene assay, the binding between miRNA-19b-3p and PTEN was verified. Regulatory effects of miRNA-19b-3p and PTEN on apoptotic rate and apoptosis-associated gene expressions (proapoptotic protein Bcl-2 associated X protein (Bax), antiapoptotic protein B-cell lymphoma-2 (Bcl-2), and cytochrome C) in H/R-induced human cardiac myocytes (HCM) cells were examined. Results. miRNA-19b-3p was upregulated, while PTEN was downregulated in H/R-induced HCM cells. Knockdown of miRNA-19b-3p decreased activities of LDH, MDA, and GSH-PX, but increased SOD level in H/R-induced HCM cells. The binding between miRNA-19b-3p and PTEN was confirmed. More importantly, knockdown of miRNA-19b-3p reduced apoptotic rate, downregulated proapoptosis gene expressions (Bax and cytochrome C), and upregulated antiapoptosis gene expression (Bcl-2), which were reversed by silence of PTEN. Conclusions. miRNA-19b-3p is upregulated in HCM cells undergoing hypoxia and reoxygenation, which accelerates MIRI-induced cardiomyocyte apoptosis through downregulating PTEN.

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Nucleic Acid Molecules Prepared by Monolayer Techniques

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100094140 ◽

1972 ◽

Vol 30 ◽

pp. 178-179

Author(s):

Dimitrij Lang

Keyword(s):

Electron Microscopy ◽

Standard Deviation ◽

Nucleic Acid ◽

Cytochrome C ◽

Nucleic Acids ◽

Contour Length ◽

Sample Standard Deviation ◽

Molecular Weights ◽

Length Measurements ◽

Protein Monolayer

The success of the protein monolayer technique for electron microscopy of individual DNA molecules is based on the prevention of aggregation and orientation of the molecules during drying on specimen grids. DNA adsorbs first to a surface-denatured, insoluble cytochrome c monolayer which is then transferred to grids, without major distortion, by touching. Fig. 1 shows three basic procedures which, modified or not, permit the study of various important properties of nucleic acids, either in concert with other methods or exclusively:1) Molecular weights relative to DNA standards as well as number distributions of molecular weights can be obtained from contour length measurements with a sample standard deviation between 1 and 4%.

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Activation of cytochrome c to a peroxidase compound I-type intermediate by H2O2: relevance to redox signalling in apoptosis

Biochemical Society Symposium ◽

10.1042/bss0710097 ◽

2004 ◽

Vol 71 ◽

pp. 97-106 ◽

Cited By ~ 10

Author(s):

Mark Burkitt ◽

Clare Jones ◽

Andrew Lawrence ◽

Peter Wardman

Keyword(s):

Cytochrome C ◽

Hydroxyl Radical ◽

Redox Regulation ◽

Chemotherapeutic Agents ◽

Tyrosyl Radical ◽

Compound I ◽

Definitive Evidence ◽

Enhanced Production ◽

Physico Chemical

The release of cytochrome c from mitochondria during apoptosis results in the enhanced production of superoxide radicals, which are converted to H2O2 by Mn-superoxide dismutase. We have been concerned with the role of cytochrome c/H2O2 in the induction of oxidative stress during apoptosis. Our initial studies showed that cytochrome c is a potent catalyst of 2′,7′-dichlorofluorescin oxidation, thereby explaining the increased rate of production of the fluorophore 2′,7′-dichlorofluorescein in apoptotic cells. Although it has been speculated that the oxidizing species may be a ferryl-haem intermediate, no definitive evidence for the formation of such a species has been reported. Alternatively, it is possible that the hydroxyl radical may be generated, as seen in the reaction of certain iron chelates with H2O2. By examining the effects of radical scavengers on 2′,7′-dichlorofluorescin oxidation by cytochrome c/H2O2, together with complementary EPR studies, we have demonstrated that the hydroxyl radical is not generated. Our findings point, instead, to the formation of a peroxidase compound I species, with one oxidizing equivalent present as an oxo-ferryl haem intermediate and the other as the tyrosyl radical identified by Barr and colleagues [Barr, Gunther, Deterding, Tomer and Mason (1996) J. Biol. Chem. 271, 15498-15503]. Studies with spin traps indicated that the oxo-ferryl haem is the active oxidant. These findings provide a physico-chemical basis for the redox changes that occur during apoptosis. Excessive changes (possibly catalysed by cytochrome c) may have implications for the redox regulation of cell death, including the sensitivity of tumour cells to chemotherapeutic agents.

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