Exogenous ubiquitin attenuates hypoxia/reoxygenation-induced cardiac myocyte apoptosis via the involvement of CXCR4 and modulation of mitochondrial homeostasis

Exogenous ubiquitin (UB) plays a protective role in β-adrenergic receptor-stimulated and ischemia/reperfusion (I/R)-induced myocardial remodeling. Here, we report that UB treatment inhibits hypoxia/reoxygenation (H/R)-induced apoptosis in adult rat ventricular myocytes (ARVMs). The activation of Akt was elevated, whereas the activation of glycogen synthase kinase-3β was reduced in UB-treated cells post-H/R. The level of oxidative stress was lower, whereas the number of ARVMs with polarized mitochondria was significantly greater in the UB-treated samples. ARVMs express CXCR4 with majority of CXCR4 localized in the membrane fraction. CXCR4 antagonism using AMD3100, and siRNA-mediated knockdown of CXCR4 negated the protective effects of UB. Two mutated UB proteins (unable to bind CXCR4) had no effect on H/R-induced apoptosis, activation of Akt and GSK-3β, or oxidative stress. UB treatment enhanced mitochondrial biogenesis, and inhibition of mitochondrial fission using mdivi1 inhibited H/R-induced apoptosis. Ex vivo, UB treatment significantly decreased infarct size and improved functional recovery of the heart following global I/R. Activation of caspase-9, a key player of the mitochondrial death pathway, was significantly lower in UB-treated hearts post-I/R. UB, most likely acting via CXCR4, plays a protective role in H/R-induced myocyte apoptosis and myocardial I/R injury via modulation of mitochondrial homeostasis and the mitochondrial death pathway of apoptosis.

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The Long Noncoding RNA Hotair Regulates Oxidative Stress and Cardiac Myocyte Apoptosis during Ischemia-Reperfusion Injury

Oxidative Medicine and Cellular Longevity ◽

10.1155/2020/1645249 ◽

2020 ◽

Vol 2020 ◽

pp. 1-19 ◽

Cited By ~ 3

Author(s):

Kai Meng ◽

Jiao Jiao ◽

Rui-Rui Zhu ◽

Bo-Yuan Wang ◽

Xiao-Bo Mao ◽

...

Keyword(s):

Oxidative Stress ◽

Calcium Binding ◽

Cardiac Myocyte ◽

Heart Diseases ◽

Ischemia Reperfusion ◽

Negative Regulator ◽

Dependent Manner ◽

Myocyte Apoptosis ◽

Cardiac Myocyte Apoptosis

Oxidative stress and subsequent cardiac myocyte apoptosis play central roles in the initiation and progression of myocardial ischemia-reperfusion (I/R) injury. Homeobox transcript antisense intergenic RNA (Hotair) was previously implicated in various heart diseases, yet its role in myocardial I/R injury has not been clearly demonstrated. Mice with cardiac-restricted knockdown or overexpression of Hotair were exposed to I/R surgery. H9c2 cells were cultured and subjected to hypoxia/reoxygenation (H/R) stimulation to further verify the role and underlying mechanisms of Hotair in vitro. Histological examination, molecular detection, and functional parameters were determined in vivo and in vitro. In response to I/R or H/R treatment, Hotair expression was increased in a bromodomain-containing protein 4-dependent manner. Cardiac-restricted knockdown of Hotair exacerbated, whereas Hotair overexpression prevented I/R-induced oxidative stress, cardiac myocyte apoptosis, and cardiac dysfunction. Mechanistically, we observed that Hotair exerted its beneficial effects via activating AMP-activated protein kinase alpha (AMPKα). Further detection revealed that Hotair activated AMPKα through regulating the enhancer of zeste homolog 2/microRNA-451/calcium-binding protein 39 (EZH2/miR-451/Cab39) axis. We provide the evidence that endogenous lncRNA Hotair is an essential negative regulator for oxidative stress and cardiac myocyte apoptosis in myocardial I/R injury, which is dependent on AMPKα activation via the EZH2/miR-451/Cab39 axis.

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CEBPA-AS1 knockdown alleviates OGD/R-induced neuron cell damage by the miR-24-3p/BOK axis

Molecular and Cellular Biology ◽

10.1128/mcb.00065-21 ◽

2021 ◽

Author(s):

Guangfu Di ◽

Xinjie Yang ◽

Feng Cheng ◽

Hua Liu ◽

Min Xu

Keyword(s):

Oxidative Stress ◽

Noncoding Rna ◽

Cell Damage ◽

Ischemia Reperfusion ◽

Glucose Deprivation ◽

Protective Role ◽

Luciferase Reporter ◽

Induced Neuron ◽

Induced Apoptosis

Cerebral ischemia/reperfusion (I/R) can lead to serious brain function impairments. Long noncoding RNA (lncRNA) CCAAT enhancer binding protein α antisense RNA 1 (CEBPA-AS1) was shown to be upregulated in human ischemic stroke. This work investigated the function and mechanism of CEBPA-AS1 in I/R. An oxygen-glucose deprivation/reperfusion (OGD/R) model was used to induce I/R injury in SH-SY5Y cells in vitro. RT-qPCR examined the expression of CEBPA-AS1, microRNA-24-3p (miR-24-3p), and Bcl-2-related ovarian killer (Bok). The cell viability, apoptosis, oxidative stress in OGD/R-treated cells were detected using CCK-8, flow cytometry, western blot, ELISA assays. The relationship among genes was tested by RNA pulldown and luciferase reporter assays. We found that OGD/R upregulated CEBPA-AS1 expression in SH-SY5Y cells. Functionally, CEBPA-AS1 depletion ameliorated OGD/R-induced apoptosis and oxidative stress in SH-SY5Y cells by reducing ROS production and superoxide dismutase (SOD) and glutathione (GSH). Mechanistic investigations indicated that CEBPA-AS1 acts as a sponge for miR-24-3p, and miR-24-3p binds to the BOK. Moreover, miR-24-3p upregulation or BOK downregulation antagonized the protective role of CEBPA-AS1 depletion in SH-SY5Y cells exposed to OGD/R. Overall, downregulation of CEBPA-AS1 exerts protective functions against OGD/R-induced injury by targeting the miR-24-3p/BOK axis.

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Dapagliflozin attenuates hypoxia/reoxygenation-caused cardiac dysfunction and oxidative damage through modulation of AMPK

Cell & Bioscience ◽

10.1186/s13578-021-00547-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Kun-Ling Tsai ◽

Pei-Ling Hsieh ◽

Wan-Ching Chou ◽

Hui-Ching Cheng ◽

Yu-Ting Huang ◽

...

Keyword(s):

Oxidative Stress ◽

Nadph Oxidase ◽

Cardiac Dysfunction ◽

Ischemia Reperfusion ◽

H9c2 Cells ◽

Mitochondrial Dna Copy Number ◽

Sodium Glucose Cotransporter ◽

Induced Apoptosis ◽

Hypoxia Reoxygenation

Abstract Background Emerging evidence demonstrated dapagliflozin (DAPA), a sodium-glucose cotransporter 2 inhibitor, prevented various cardiovascular events. However, the detailed mechanisms underlying its cardioprotective properties remained largely unknown. Results In the present study, we sought to investigate the effects of DAPA on the cardiac ischemia/reperfusion (I/R) injury. Results from in vitro experiments showed that DAPA induced the phosphorylation of AMPK, resulting in the downregulation of PKC in the cardiac myoblast H9c2 cells following hypoxia/reoxygenation (H/R) condition. We demonstrated that DAPA treatment diminished the H/R-elicited oxidative stress via the AMPK/ PKC/ NADPH oxidase pathway. In addition, DAPA prevented the H/R-induced abnormality of PGC-1α expression, mitochondrial membrane potential, and mitochondrial DNA copy number through AMPK/ PKC/ NADPH oxidase signaling. Besides, DAPA reversed the H/R-induced apoptosis. Furthermore, we demonstrated that DAPA improved the I/R-induced cardiac dysfunction by echocardiography and abrogated the I/R-elicited apoptosis in the myocardium of rats. Also, the administration of DAPA mitigated the production of myocardial infarction markers. Conclusions In conclusion, our data suggested that DAPA treatment holds the potential to ameliorate the I/R-elicited oxidative stress and the following cardiac apoptosis via modulation of AMPK, which attenuates the cardiac dysfunction caused by I/R injury.

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Protective Role of Glutathione in the Hippocampus after Brain Ischemia

International Journal of Molecular Sciences ◽

10.3390/ijms22157765 ◽

2021 ◽

Vol 22 (15) ◽

pp. 7765

Author(s):

Youichirou Higashi ◽

Takaaki Aratake ◽

Takahiro Shimizu ◽

Shogo Shimizu ◽

Motoaki Saito

Keyword(s):

Oxidative Stress ◽

Neuronal Death ◽

Excitatory Amino Acid ◽

Ischemia Reperfusion ◽

Thiol Group ◽

Protective Role ◽

Key Factor ◽

Rate Limiting ◽

Cysteine Uptake

Stroke is a major cause of death worldwide, leading to serious disability. Post-ischemic injury, especially in the cerebral ischemia-prone hippocampus, is a serious problem, as it contributes to vascular dementia. Many studies have shown that in the hippocampus, ischemia/reperfusion induces neuronal death through oxidative stress and neuronal zinc (Zn2+) dyshomeostasis. Glutathione (GSH) plays an important role in protecting neurons against oxidative stress as a major intracellular antioxidant. In addition, the thiol group of GSH can function as a principal Zn2+ chelator for the maintenance of Zn2+ homeostasis in neurons. These lines of evidence suggest that neuronal GSH levels could be a key factor in post-stroke neuronal survival. In neurons, excitatory amino acid carrier 1 (EAAC1) is involved in the influx of cysteine, and intracellular cysteine is the rate-limiting substrate for the synthesis of GSH. Recently, several studies have indicated that cysteine uptake through EAAC1 suppresses ischemia-induced neuronal death via the promotion of hippocampal GSH synthesis in ischemic animal models. In this article, we aimed to review and describe the role of GSH in hippocampal neuroprotection after ischemia/reperfusion, focusing on EAAC1.

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Interleukin 35 protects cardiomyocytes following ischemia/reperfusion-induced apoptosis via activation of mitochondrial STAT3

Acta Biochimica et Biophysica Sinica ◽

10.1093/abbs/gmab007 ◽

2021 ◽

Author(s):

Fengyun Zhou ◽

Ting Feng ◽

Xiangqi Lu ◽

Huicheng Wang ◽

Yangping Chen ◽

...

Keyword(s):

Ischemia Reperfusion Injury ◽

Ischemia Reperfusion ◽

Protective Role ◽

Cytochrome C Release ◽

Neonatal Cardiomyocytes ◽

Myocardial Ischemia Reperfusion Injury ◽

Myocardial Ischemia Reperfusion ◽

Underlying Mechanisms ◽

Induced Apoptosis

Abstract Mitochondrial reactive oxygen species (mtROS)-induced apoptosis has been suggested to contribute to myocardial ischemia/reperfusion injury. Interleukin 35 (IL-35), a novel anti-inflammatory cytokine, has been shown to protect the myocardium and inhibit mtROS production. However, its effect on cardiomyocytes upon exposure to hypoxia/reoxygenation (H/R) damage has not yet been elucidated. The present study aimed to investigate the potential protective role and underlying mechanisms of IL-35 in H/R-induced mouse neonatal cardiomyocyte injury. Mouse neonatal cardiomyocytes were challenged to H/R in the presence of IL-35, and we found that IL-35 dose dependently promotes cell viability, diminishes mtROS, maintains mitochondrial membrane potential, and decreases the number of apoptotic cardiomyocytes. Meanwhile, IL-35 remarkably activates mitochondrial STAT3 (mitoSTAT3) signaling, inhibits cytochrome c release, and reduces apoptosis signaling. Furthermore, co-treatment of the cardiomyocytes with the STAT3 inhibitor AG490 abrogates the IL-35-induced cardioprotective effects. Our study identified the protective role of IL-35 in cardiomyocytes following H/R damage and revealed that IL-35 protects cardiomyocytes against mtROS-induced apoptosis through the mitoSTAT3 signaling pathway during H/R.

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Fetuin-A exerts a protective effect against experimentally induced intestinal ischemia/reperfusion by suppressing autophagic cell death

Experimental Biology and Medicine ◽

10.1177/1535370221995207 ◽

2021 ◽

pp. 153537022199520

Author(s):

Nanees F El-Malkey ◽

Amira E Alsemeh ◽

Wesam MR Ashour ◽

Nancy H Hassan ◽

Husam M Edrees

Keyword(s):

Oxidative Stress ◽

Rat Model ◽

Intestinal Ischemia ◽

Ischemia Reperfusion ◽

Protective Role ◽

Beclin 1 ◽

Male Rats ◽

Fetuin A ◽

Intestinal Ischemia Reperfusion ◽

And Oxidative Stress

Intestinal tissue is highly susceptible to ischemia/reperfusion injury in many hazardous health conditions. The anti-inflammatory and antioxidant glycoprotein fetuin-A showed efficacy in cerebral ischemic injury; however, its protective role against intestinal ischemia/reperfusion remains elusive. Therefore, this study investigated the protective role of fetuin-A supplementation against intestinal structural changes and dysfunction in a rat model of intestinal ischemia/reperfusion. We equally divided 72 male rats into control, sham, ischemia/reperfusion, and fetuin-A-pretreated ischemia/reperfusion (100 mg/kg/day fetuin-A intraperitoneally for three days prior to surgery and a third dose 1 h prior to the experiment) groups. After 2 h of reperfusion, the jejunum was dissected and examined for spontaneous contractility. A jejunal homogenate was used to assess inflammatory and oxidative stress enzymes. Staining of histological sections was carried out with hematoxylin, eosin and Masson’s trichrome stain for evaluation. Immunohistochemistry was performed to detect autophagy proteins beclin-1, LC3, and p62. This study found that fetuin-A significantly improved ischemia/reperfusion-induced mucosal injury by reducing the percentage of areas of collagen deposition, increasing the amplitude of spontaneous contraction, decreasing inflammation and oxidative stress, and upregulating p62 expression, which was accompanied by beclin-1 and LC3 downregulation. Our findings suggest that fetuin-A treatment can prevent ischemia/reperfusion-induced jejunal structural and functional changes by increasing antioxidant activity and regulating autophagy disturbances observed in the ischemia/reperfusion rat model. Furthermore, fetuin-A may provide a protective influence against intestinal ischemia/reperfusion complications.

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Overexpression of miR-431 attenuates hypoxia/reoxygenation-induced myocardial damage via autophagy-related 3

Acta Biochimica et Biophysica Sinica ◽

10.1093/abbs/gmaa154 ◽

2020 ◽

Author(s):

Kang Zhou ◽

Yan Xu ◽

Qiong Wang ◽

Lini Dong

Keyword(s):

Cell Viability ◽

Cell Apoptosis ◽

Myocardial Injury ◽

Ischemia Reperfusion Injury ◽

Ischemia Reperfusion ◽

Myocardial Damage ◽

Protective Role ◽

Human Cardiomyocytes ◽

Hypoxia Reoxygenation

Abstract Myocardial injury is still a serious condition damaging the public health. Clinically, myocardial injury often leads to cardiac dysfunction and, in severe cases, death. Reperfusion of the ischemic myocardial tissues can minimize acute myocardial infarction (AMI)-induced damage. MicroRNAs are commonly recognized in diverse diseases and are often involved in the development of myocardial ischemia/reperfusion injury. However, the role of miR-431 remains unclear in myocardial injury. In this study, we investigated the underlying mechanisms of miR-431 in the cell apoptosis and autophagy of human cardiomyocytes in hypoxia/reoxygenation (H/R). H/R treatment reduced cell viability, promoted cell apoptotic rate, and down-regulated the expression of miR-431 in human cardiomyocytes. The down-regulation of miR-431 by its inhibitor reduced cell viability and induced cell apoptosis in the human cardiomyocytes. Moreover, miR-431 down-regulated the expression of autophagy-related 3 (ATG3) via targeting the 3ʹ-untranslated region of ATG3. Up-regulated expression of ATG3 by pcDNA3.1-ATG3 reversed the protective role of the overexpression of miR-431 on cell viability and cell apoptosis in H/R-treated human cardiomyocytes. More importantly, H/R treatments promoted autophagy in the human cardiomyocytes, and this effect was greatly alleviated via miR-431-mimic transfection. Our results suggested that miR-431 overexpression attenuated the H/R-induced myocardial damage at least partly through regulating the expression of ATG3.

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Abstract 172: Thrombopoietin Receptor Agonists Protect Human Cardiac Myocytes from Injury by Activation of Cell Survival Pathways

Circulation ◽

10.1161/circ.130.suppl_2.172 ◽

2014 ◽

Vol 130 (suppl_2) ◽

Author(s):

John E Baker ◽

Jidong Su ◽

Stacy Koprowski ◽

Anuradha Dhanasekaran ◽

Tom P Aufderheide ◽

...

Keyword(s):

Cardiac Myocytes ◽

Cardiac Myocyte ◽

Apoptotic Cell ◽

Ischemia Reperfusion ◽

Dependent Manner ◽

Concentration Dependent Manner ◽

Survival Pathways ◽

Thrombopoietin Receptor ◽

Reoxygenation Injury ◽

Hypoxia Reoxygenation

Thrombopoietin confers immediate protection against injury caused by ischemia/reperfusion in the rat heart at a dose that does not increase platelet levels. Eltrombopag is a small molecule agonist of the thrombopoietin receptor; the physiological target of thrombopoietin. Administration of thrombopoietin and eltrombopag result in a dose- and time-dependent increase in platelet counts in patients with thrombocytopenia. However, the ability of eltrombopag and thrombopoietin to immediately protect human cardiac myocytes against injury and the mechanisms underlying myocyte protection are not known. Human cardiac myocytes (7500 cells, n=10/group) were treated with eltrombopag (0.1- 30.0 μM) or thrombopoietin ( 0.1 - 30.0 ng/ml) and then subjected to 5 hours of hypoxia (95% N 2 /5%CO 2 ) and 16 hours of reoxygenation to determine their ability to confer resistance to necrotic and apoptotic myocardial injury . The thrombopoietin receptor (c-Mpl) was detected in unstimulated human cardiac myocytes by western blotting. Eltrombopag and thrombopoietin confer immediate protection to human cardiac myocytes against injury from hypoxia/reoxygenation by decreasing necrotic and apoptotic cell death in a concentration-dependent manner with an optimal concentration of 3 μM for eltrombopag and 1.0 ng/ml for thrombopoietin. The extent of protection conferred to cardiac myocytes with eltrombopag is equivalent to that of thrombopoietin. Eltrombopag and thrombopoietin activate multiple pro-survival pathways; inhibition of JAK-2 (AG-490, 10 μM), p38 MAPK (SB203580, 10 μM), p44/42 MAPK (PD98059, 10 μM), Akt/PI 3 kinase (Wortmannin, 100 nM), and src kinase (PP1, 20 μM) prior to and during hypoxia abolished cardiac myocyte protection by eltrombopag and thrombopoietin. These inhibitors had no effect on hypoxia/reoxygenation injury in myocytes when used alone. Eltrombopag and thrombopoietin may represent important and potent agents for immediately and substantially increasing protection of human cardiac myocytes, and may offer long-lasting benefit through activation of pro-survival pathways during ischemia.

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