Inhibition of Neuronal Necroptosis Mediated by RIPK1 Provides Neuroprotective Effects on Hypoxia and Ischemia In Vitro and In Vivo

Ischemic brain injury is a widespread pathological condition, the main components of which are a deficiency of oxygen and energy substrates. In recent years, a number of new forms of cell death, including necroptosis, have been described. In necroptosis, a cascade of interactions between the kinases RIPK1 and RIPK3 and the MLKL protein leads to the formation of a specialized death complex called the necrosome, which triggers MLKL-mediated destruction of the cell membrane and necroptotic cell death. Necroptosis probably plays an important role in the development of ischemia/reperfusion injury and can be considered as a potential target for finding methods to correct the disruption of neural networks in ischemic damage. In the present study, we demonstrated that blockade of RIPK1 kinase by Necrostatin-1 preserved the viability of cells in primary hippocampal cultures in an in vitro model of glucose deprivation. The effect of RIPK1 blockade on the bioelectrical and metabolic calcium activity of neuron-glial networks in vitro using calcium imaging and multi-electrode arrays was assessed for the first time. RIPK1 blockade was shown to partially preserve both calcium and bioelectric activity of neuron-glial networks under ischemic factors. However, it should be noted that RIPK1 blockade does not preserve the network parameters of the collective calcium dynamics of neuron-glial networks, despite the maintenance of network bioelectrical activity (the number of bursts and the number of spikes in the bursts). To confirm the data obtained in vitro, we studied the effect of RIPK1 blockade on the resistance of small laboratory animals to in vivo modeling of hypoxia and cerebral ischemia. The use of Necrostatin-1 increases the survival rate of C57BL mice in modeling both acute hypobaric hypoxia and ischemic brain damage.

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Up-regulation of MicroRNA-21 Mediates Isoflurane-induced Protection of Cardiomyocytes

Anesthesiology ◽

10.1097/aln.0000000000000567 ◽

2015 ◽

Vol 122 (4) ◽

pp. 795-805 ◽

Cited By ~ 29

Author(s):

Jessica M. Olson ◽

Yasheng Yan ◽

Xiaowen Bai ◽

Zhi-Dong Ge ◽

Mingyu Liang ◽

...

Keyword(s):

Cell Death ◽

Programmed Cell Death ◽

Messenger Rna ◽

Functional Role ◽

Ischemia Reperfusion Injury ◽

Ischemia Reperfusion ◽

Cell Death Protein

Abstract Background: Anesthetic cardioprotection reduces myocardial infarct size after ischemia–reperfusion injury. Currently, the role of microRNA in this process remains unknown. MicroRNAs are short, noncoding nucleotide sequences that negatively regulate gene expression through degradation or suppression of messenger RNA. In this study, the authors uncovered the functional role of microRNA-21 (miR-21) up-regulation after anesthetic exposure. Methods: MicroRNA and messenger RNA expression changes were analyzed by quantitative real-time polymerase chain reaction in cardiomyocytes after exposure to isoflurane. Lactate dehydrogenase release assay and propidium iodide staining were conducted after inhibition of miR-21. miR-21 target expression was analyzed by Western blot. The functional role of miR-21 was confirmed in vivo in both wild-type and miR-21 knockout mice. Results: Isoflurane induces an acute up-regulation of miR-21 in both in vivo and in vitro rat models (n = 6, 247.8 ± 27.5% and 258.5 ± 9.0%), which mediates protection to cardiomyocytes through down-regulation of programmed cell death protein 4 messenger RNA (n = 3, 82.0 ± 4.9% of control group). This protective effect was confirmed by knockdown of miR-21 and programmed cell death protein 4 in vitro. In addition, the protective effect of isoflurane was abolished in miR-21 knockout mice in vivo, with no significant decrease in infarct size compared with nonexposed controls (n = 8, 62.3 ± 4.6% and 56.2 ± 3.2%). Conclusions: The authors demonstrate for the first time that isoflurane mediates protection of cardiomyocytes against oxidative stress via an miR-21/programmed cell death protein 4 pathway. These results reveal a novel mechanism by which the damage done by ischemia/reperfusion injury may be decreased.

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Critical Roles of Calpastatin in Ischemia/Reperfusion Injury in Aged Livers

Cells ◽

10.3390/cells10081863 ◽

2021 ◽

Vol 10 (8) ◽

pp. 1863

Author(s):

Joseph Flores-Toro ◽

Sung-Kook Chun ◽

Jun-Kyu Shin ◽

Joan Campbell ◽

Melissa Lichtenberger ◽

...

Keyword(s):

Cell Death ◽

Mitochondrial Permeability Transition ◽

Ischemia Reperfusion Injury ◽

Ischemia Reperfusion ◽

Age Groups ◽

Permeability Transition ◽

Mitochondrial Morphology ◽

Human And Mouse

Ischemia/reperfusion (I/R) injury unavoidably occurs during hepatic resection and transplantation. Aged livers poorly tolerate I/R during surgical treatment. Although livers have a powerful endogenous inhibitor of calpains, calpastatin (CAST), I/R activates calpains, leading to impaired autophagy, mitochondrial dysfunction, and hepatocyte death. It is unknown how I/R in aged livers affects CAST. Human and mouse liver biopsies at different ages were collected during in vivo I/R. Hepatocytes were isolated from 3-month- (young) and 26-month-old (aged) mice, and challenged with short in vitro simulated I/R. Cell death, protein expression, autophagy, and mitochondrial permeability transition (MPT) between the two age groups were compared. Adenoviral vector was used to overexpress CAST. Significant cell death was observed only in reperfused aged hepatocytes. Before the commencement of ischemia, CAST expression in aged human and mouse livers and mouse hepatocytes was markedly greater than that in young counterparts. However, reperfusion substantially decreased CAST in aged human and mouse livers. In hepatocytes, reperfusion rapidly depleted aged cells of CAST, cleaved autophagy-related protein 5 (ATG5), and induced defective autophagy and MPT onset, all of which were blocked by CAST overexpression. Furthermore, mitochondrial morphology was shifted toward an elongated shape with CAST overexpression. In conclusion, CAST in aged livers is intrinsically short-lived and lost after short I/R. CAST depletion contributes to age-dependent liver injury after I/R.

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Signal Transduction of Opioid-induced Cardioprotection in Ischemia-Reperfusion

Anesthesiology ◽

10.1097/00000542-200106000-00024 ◽

2001 ◽

Vol 94 (6) ◽

pp. 1082-1088 ◽

Cited By ~ 34

Author(s):

Bradley C. McPherson ◽

Zhenhai Yao

Keyword(s):

Cell Death ◽

Opioid Receptor ◽

Oxygen Radicals ◽

Ischemia Reperfusion Injury ◽

Ischemia Reperfusion ◽

Oxidant Stress ◽

Katp Channels ◽

Molecular Probe

Background Morphine reduces myocardial ischemia-reperfusion injury in vivo and in vitro. The authors tried to determine the role of opioid delta1 receptors, oxygen radicals, and adenosine triphosphate-sensitive potassium (KATP) channels in mediating this effect. Methods Chick cardiomyocytes were studied in a flow-through chamber while pH, flow rate, oxygen, and carbon dioxide tension were controlled. Cell viability was quantified by nuclear stain propidium iodide, and oxygen radicals were quantified using molecular probe 2',7'-dichlorofluorescin diacetate. Results Morphine (1 microM) or the selective delta-opioid receptor agonist BW373U86 (10 pM) given for 10 min before 1 h of ischemia and 3 h of reoxygenation reduced cell death (31 +/- 5%, n = 6, and 28 +/- 5%, n = 6 [P < 0.05], respectively, 53 +/- 6%, n = 6, in controls) and generated oxygen radicals before ischemia (724 +/- 53, n = 8, and 742 +/- 75, n = 8 [P < 0.05], respectively, vs. 384 +/- 42, n = 6, in controls, arbitrary units). The protection of morphine was abolished by naloxone, or the selective delta1-opioid receptor antagonist 7-benzylidenenaltrexone. Reduction in cell death and increase in oxygen radicals with BW373U86 were blocked by the selective mitochondrial KATP channel antagonist 5-hydroxydecanoate or diethyldithiocarbamic acid (1,000 microM), which inhibited conversion of O2- to H2O2. The increase in oxygen radicals was abolished by the mitochondrial electron transport inhibitor myxothiazoL Reduction in cell death was associated with attenuated oxidant stress at reperfusion. Conclusion Stimulation of delta1-opioid receptors generates oxygen radicals via mitochondrial KATP channels. This signaling pathway attenuates oxidant stress and cell death in cardiomyocytes.

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TRAP1 Provides Protection Against Myocardial Ischemia-Reperfusion Injury by Ameliorating Mitochondrial Dysfunction

Cellular Physiology and Biochemistry ◽

10.1159/000430174 ◽

2015 ◽

Vol 36 (5) ◽

pp. 2072-2082 ◽

Cited By ~ 21

Author(s):

Peng Zhang ◽

Yong Lu ◽

Dong Yu ◽

Dadong Zhang ◽

Wei Hu

Keyword(s):

Cell Death ◽

Mitochondrial Dysfunction ◽

Mitochondrial Function ◽

Ischemia Reperfusion Injury ◽

Ischemia Reperfusion ◽

Ros Generation ◽

Complex Activity ◽

Atp Production

Background: Tumor necrosis factor receptor-associated protein 1 (TRAP1), an essential mitochondrial chaperone is induced in rat hearts following ischemia/reperfusion (I/R), but its role in myocardial I/R injury is unclear. The present study examined the function of TRAP1 in cardiomyocyte hypoxia/reoxygenation injury in vitro and myocardial I/R injury in vivo. Methods: HL-1 cardiomyocytes transfected with TRAP1 or vector were subjected to simulated I/R (SI/R) in vitro. Cell death and mitochondrial function were assessed. Wild type (WT) and TRAP1 knockout (TRAP1 KO) mice were subjected to cardiac I/R in vivo. The infarct size and myocardial apoptosis were determined. WT and TRAP1 KO cardiomyocytes were subjected to SI/R in vitro. Mitochondrial function was assessed. Results: TRAP1 overexpression protects HL-1 cardiomyocytes from SI/R-induced cell death in vitro. The reduced cell death was associated with decreased ROS generation, better-preserved mitochondrial ETC complex activity, membrane potential, and ATP production, as well as delayed mPTP opening. Loss of TRAP1 aggravates SI/R-induced mitochondrial damage in cardiomyocytes in vitro and myocardial I/R injury and apoptosis in vivo. Conclusion: The results of the present study show that TRAP1 provides cardioprotection against myocardial I/R by ameliorating mitochondrial dysfunction.

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Regulatory T cells are strong promoters of acute ischemic stroke in mice by inducing dysfunction of the cerebral microvasculature

Blood ◽

10.1182/blood-2012-04-426734 ◽

2013 ◽

Vol 121 (4) ◽

pp. 679-691 ◽

Cited By ~ 192

Author(s):

Christoph Kleinschnitz ◽

Peter Kraft ◽

Angela Dreykluft ◽

Ina Hagedorn ◽

Kerstin Göbel ◽

...

Keyword(s):

T Cells ◽

Regulatory T Cells ◽

Ischemia Reperfusion Injury ◽

Thrombus Formation ◽

Ischemia Reperfusion ◽

T Cell Subsets ◽

Ischemic Brain

Abstract We have recently identified T cells as important mediators of ischemic brain damage, but the contribution of the different T-cell subsets is unclear. Forkhead box P3 (FoxP3)–positive regulatory T cells (Tregs) are generally regarded as prototypic anti-inflammatory cells that maintain immune tolerance and counteract tissue damage in a variety of immune-mediated disorders. In the present study, we examined the role of Tregs after experimental brain ischemia/reperfusion injury. Selective depletion of Tregs in the DEREG mouse model dramatically reduced infarct size and improved neurologic function 24 hours after stroke and this protective effect was preserved at later stages of infarct development. The specificity of this detrimental Treg effect was confirmed by adoptive transfer experiments in wild-type mice and in Rag1−/− mice lacking lymphocytes. Mechanistically, Tregs induced microvascular dysfunction in vivo by increased interaction with the ischemic brain endothelium via the LFA-1/ICAM-1 pathway and platelets and these findings were confirmed in vitro. Ablation of Tregs reduced microvascular thrombus formation and improved cerebral reperfusion on stroke, as revealed by ultra-high-field magnetic resonance imaging at 17.6 Tesla. In contrast, established immunoregulatory characteristics of Tregs had no functional relevance. We define herein a novel and unexpected role of Tregs in a primary nonimmunologic disease state.

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microRNA-377 Signaling Modulates Anticancer Drug-Induced Cardiotoxicity in Mice

Frontiers in Cardiovascular Medicine ◽

10.3389/fcvm.2021.737826 ◽

2021 ◽

Vol 8 ◽

Author(s):

John Henderson ◽

Praveen K. Dubey ◽

Mallikarjun Patil ◽

Sarojini Singh ◽

Shubham Dubey ◽

...

Keyword(s):

Cell Death ◽

Rna Sequencing ◽

Molecular Mechanisms ◽

Ischemia Reperfusion Injury ◽

Ischemia Reperfusion ◽

Drug Induced ◽

Chemotherapy Agent

Doxorubicin (DOX, an anthracycline) is a widely used chemotherapy agent against various forms of cancer; however, it is also known to induce dose-dependent cardiotoxicity leading to adverse complications. Investigating the underlying molecular mechanisms and strategies to limit DOX-induced cardiotoxicity might have potential clinical implications. Our previous study has shown that expression of microRNA-377 (miR-377) increases in cardiomyocytes (CMs) after cardiac ischemia-reperfusion injury in mice, but its specific role in DOX-induced cardiotoxicity has not been elucidated. In the present study, we investigated the effect of anti-miR-377 on DOX-induced cardiac cell death, remodeling, and dysfunction. We evaluated the role of miR-377 in CM apoptosis, its target analysis by RNA sequencing, and we tested the effect of AAV9-anti-miR-377 on DOX-induced cardiotoxicity and mortality. DOX administration in mice increases miR-377 expression in the myocardium. miR-377 inhibition in cardiomyocyte cell line protects against DOX-induced cell death and oxidative stress. Furthermore, RNA sequencing and Gene Ontology (GO) analysis revealed alterations in a number of cell death/survival genes. Intriguingly, we observed accelerated mortality and enhanced myocardial remodeling in the mice pretreated with AAV9-anti-miR-377 followed by DOX administration as compared to the AAV9-scrambled-control-pretreated mice. Taken together, our data suggest that in vitro miR-377 inhibition protects against DOX-induced cardiomyocyte cell death. On the contrary, in vivo administration of AAV9-anti-miR-377 increases mortality in DOX-treated mice.

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iPLA2β Contributes to ER Stress-Induced Apoptosis during Myocardial Ischemia/Reperfusion Injury

Cells ◽

10.3390/cells10061446 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1446

Author(s):

Tingting Jin ◽

Jun Lin ◽

Yingchao Gong ◽

Xukun Bi ◽

Shasha Hu ◽

...

Keyword(s):

Cell Death ◽

Heart Disease ◽

Myocardial Ischemia ◽

Ischemic Heart Disease ◽

Er Stress ◽

Ischemia Reperfusion ◽

Myocardial Ischemia Reperfusion ◽

Induced Apoptosis

Both calcium-independent phospholipase A2 beta (iPLA2β) and endoplasmic reticulum (ER) stress regulate important pathophysiological processes including inflammation, calcium homeostasis and apoptosis. However, their roles in ischemic heart disease are poorly understood. Here, we show that the expression of iPLA2β is increased during myocardial ischemia/reperfusion (I/R) injury, concomitant with the induction of ER stress and the upregulation of cell death. We further show that the levels of iPLA2β in serum collected from acute myocardial infarction (AMI) patients and in samples collected from both in vivo and in vitro I/R injury models are significantly elevated. Further, iPLA2β knockout mice and siRNA mediated iPLA2β knockdown are employed to evaluate the ER stress and cell apoptosis during I/R injury. Additionally, cell surface protein biotinylation and immunofluorescence assays are used to trace and locate iPLA2β. Our data demonstrate the increase of iPLA2β augments ER stress and enhances cardiomyocyte apoptosis during I/R injury in vitro and in vivo. Inhibition of iPLA2β ameliorates ER stress and decreases cell death. Mechanistically, iPLA2β promotes ER stress and apoptosis by translocating to ER upon myocardial I/R injury. Together, our study suggests iPLA2β contributes to ER stress-induced apoptosis during myocardial I/R injury, which may serve as a potential therapeutic target against ischemic heart disease.

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N6-methyladenosine demethylase FTO impairs hepatic ischemia–reperfusion injury via inhibiting Drp1-mediated mitochondrial fragmentation

Cell Death and Disease ◽

10.1038/s41419-021-03622-x ◽

2021 ◽

Vol 12 (5) ◽

Author(s):

Ying Dong Du ◽

Wen Yuan Guo ◽

Cong Hui Han ◽

Ying Wang ◽

Xiao Song Chen ◽

...

Keyword(s):

Reperfusion Injury ◽

Ischemia Reperfusion Injury ◽

Ischemia Reperfusion ◽

Mitochondrial Fragmentation ◽

Hepatic Ischemia ◽

Adeno Associated Virus ◽

Downstream Target ◽

Hepatic Ischemia Reperfusion

AbstractDespite N6-methyladenosine (m6A) is functionally important in various biological processes, its role and the underlying regulatory mechanism in the liver remain largely unexplored. In the present study, we showed that fat mass and obesity-associated protein (FTO, an m6A demethylase) was involved in mitochondrial function during hepatic ischemia–reperfusion injury (HIRI). We found that the expression of m6A demethylase FTO was decreased during HIRI. In contrast, the level of m6A methylated RNA was enhanced. Adeno-associated virus-mediated liver-specific overexpression of FTO (AAV8-TBG-FTO) ameliorated the HIRI, repressed the elevated level of m6A methylated RNA, and alleviated liver oxidative stress and mitochondrial fragmentation in vivo and in vitro. Moreover, dynamin-related protein 1 (Drp1) was a downstream target of FTO in the progression of HIRI. FTO contributed to the hepatic protective effect via demethylating the mRNA of Drp1 and impairing the Drp1-mediated mitochondrial fragmentation. Collectively, our findings demonstrated the functional importance of FTO-dependent hepatic m6A methylation during HIRI and provided valuable insights into the therapeutic mechanisms of FTO.

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Propofol attenuates lung ischemia/reperfusion injury though the involvement of the MALAT1/microRNA-144/GSK3β axis

Molecular Medicine ◽

10.1186/s10020-021-00332-0 ◽

2021 ◽

Vol 27 (1) ◽

Author(s):

Jian-Ping Zhang ◽

Wei-Jing Zhang ◽

Miao Yang ◽

Hua Fang

Keyword(s):

Cell Apoptosis ◽

Ischemia Reperfusion Injury ◽

Glycogen Synthase ◽

Ischemia Reperfusion ◽

Inflammatory Factors ◽

Therapeutic Effects ◽

Protective Effects ◽

Loss Of Function

Abstract Background Propofol, an intravenous anesthetic, was proven to protect against lung ischemia/reperfusion (I/R) injury. However, the detailed mechanism of Propofol in lung I/R injury is still elusive. This study was designed to explore the therapeutic effects of Propofol, both in vivo and in vitro, on lung I/R injury and the underlying mechanisms related to metastasis-associated lung adenocarcinoma transcript 1 (MALAT1)/microRNA-144 (miR-144)/glycogen synthase kinase-3β (GSK3β). Methods C57BL/6 mice were used to establish a lung I/R injury model while pulmonary microvascular endothelial cells (PMVECs) were constructed as hypoxia/reperfusion (H/R) cellular model, both of which were performed with Propofol treatment. Gain- or loss-of-function approaches were subsequently employed, followed by observation of cell apoptosis in lung tissues and evaluation of proliferative and apoptotic capabilities in H/R cells. Meanwhile, the inflammatory factors, autophagosomes, and autophagy-related proteins were measured. Results Our experimental data revealed that Propofol treatment could decrease the elevated expression of MALAT1 following I/R injury or H/R induction, indicating its protection against lung I/R injury. Additionally, overexpressing MALAT1 or GSK3β promoted the activation of autophagosomes, proinflammatory factor release, and cell apoptosis, suggesting that overexpressing MALAT1 or GSK3β may reverse the protective effects of Propofol against lung I/R injury. MALAT1 was identified to negatively regulate miR-144 to upregulate the GSK3β expression. Conclusion Overall, our study demonstrated that Propofol played a protective role in lung I/R injury by suppressing autophagy and decreasing release of inflammatory factors, with the possible involvement of the MALAT1/miR-144/GSK3β axis.

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LINGO-1 shRNA protects the brain against ischemia/reperfusion injury by inhibiting the activation of NF-κB and JAK2/STAT3

Human Cell ◽

10.1007/s13577-021-00527-x ◽

2021 ◽

Author(s):

Jiaying Zhu ◽

Zhu Zhu ◽

Yipin Ren ◽

Yukang Dong ◽

Yaqi Li ◽

...

Keyword(s):

Cerebral Ischemia ◽

Nuclear Translocation ◽

Ischemia Reperfusion Injury ◽

Ischemia Reperfusion ◽

Glucose Deprivation ◽

Artery Occlusion ◽

Mice Model ◽

Down Regulation

AbstractLINGO-1 may be involved in the pathogenesis of cerebral ischemia. However, its biological function and underlying molecular mechanism in cerebral ischemia remain to be further defined. In our study, middle cerebral artery occlusion/reperfusion (MACO/R) mice model and HT22 cell oxygen–glucose deprivation/reperfusion (OGD/R) were established to simulate the pathological process of cerebral ischemia in vivo and in vitro and to detect the relevant mechanism. We found that LINGO-1 mRNA and protein were upregulated in mice and cell models. Down-regulation LINGO-1 improved the neurological symptoms and reduced pathological changes and the infarct size of the mice after MACO/R. In addition, LINGO-1 interference alleviated apoptosis and promoted cell proliferation in HT22 of OGD/R. Moreover, down-regulation of LINGO-1 proved to inhibit nuclear translocation of p-NF-κB and reduce the expression level of p-JAK2 and p-STAT3. In conclusion, our data suggest that shLINGO-1 attenuated ischemic injury by negatively regulating NF-KB and JAK2/STAT3 pathways, highlighting a novel therapeutic target for ischemic stroke.

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