EFFECT OF COLCHICINE AND ATORVASTATIN ON CELL DEATH MECHANISMS DURING INFLAMMATORY PROCESSES IN ATHEROSCHLEROSIS

The acute demise of stem cells following transplantation significantly compromises the efficacy of stem cell-based cell therapeutics for infarcted hearts. As the stem cells transplanted into the damaged heart are readily exposed to the hostile environment, it can be assumed that the acute death of the transplanted stem cells is also inflicted by the same environmental cues that caused massive death of the host cardiac cells. Pyroptosis, a highly inflammatory form of programmed cell death, has been added to the list of important cell death mechanisms in the damaged heart. However, unlike the well-established cell death mechanisms such as necrosis or apoptosis, the exact role and significance of pyroptosis in the acute death of transplanted stem cells have not been explored in depth. In the present study, we found that M1 macrophages mediate the pyroptosis in the ischemia/reperfusion (I/R) injured hearts and identified miRNA-762 as an important regulator of interleukin 1b production and subsequent pyroptosis. Delivery of exogenous miRNA-762 prior to transplantation significantly increased the post-transplant survival of stem cells and also significantly ameliorated cardiac fibrosis and heart functions following I/R injury. Our data strongly suggest that suppressing pyroptosis can be an effective adjuvant strategy to enhance the efficacy of stem cell-based therapeutics for diseased hearts.

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Apoptosis and inflammation

Mediators of Inflammation ◽

10.1155/s0962935195000020 ◽

1995 ◽

Vol 4 (1) ◽

pp. 5-15 ◽

Cited By ~ 68

Author(s):

C. Haanen ◽

I. Vermes

Keyword(s):

Cell Death ◽

Inflammatory Reaction ◽

Inflammatory Diseases ◽

Apoptotic Cell ◽

Cell Damage ◽

Target Cells ◽

Apoptotic Bodies ◽

Accidental Injury ◽

Inflammatory Reactions ◽

Inflammatory Processes

During the last few decades it has been recognized that cell death is not the consequence of accidental injury, but is the expression of a cell suicide programme. Kerr et al. (1972) introduced the term apoptosis. This form of cell death is under the influence of hormones, growth factors and cytokines, which depending upon the receptors present on the target cells, may activate a genetically controlled cell elimination process. During apoptosis the cell membrane remains intact and the cell breaks into apoptotic bodies, which are phagocytosed. Apoptosis, in contrast to necrosis, is not harmful to the host and does not induce any inflammatory reaction. The principal event that leads to inflammatory disease is cell damage, induced by chemical/physical injury, anoxia or starvation. Cell damage means leakage of cell contents into the adjacent tissues, resulting in the capillary transmigration of granulocytes to the injured tissue. The accumulation of neutrophils and release of enzymes and oxygen radicals enhances the inflammatory reaction. Until now there has been little research into the factors controlling the accumulation and the tissue load of granulocytes and their histotoxic products in inflammatory processes. Neutrophil apoptosis may represent an important event in the control of intlamtnation. It has been assumed that granulocytes disintegrate to apoptotic bodies before their fragments are removed by local macrophages. Removal of neutrophils from the inflammatory site without release of granule contents is of paramount importance for cessation of inflammation. In conclusion, apoptotic cell death plays an important role in inflammatory processes and in the resolution of inflammatory reactions. The facts known at present should stimulate further research into the role of neutrophil, eosinophil and macrophage apoptosis in inflammatory diseases.

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Mitochondrion-Dependent Cell Death in TDP-43 Proteinopathies

Biomedicines ◽

10.3390/biomedicines9040376 ◽

2021 ◽

Vol 9 (4) ◽

pp. 376

Author(s):

Chantal B. Lucini ◽

Ralf J. Braun

Keyword(s):

Cell Death ◽

Oxygen Species ◽

In Vivo Models ◽

Dependent Cell ◽

Cell Death Mechanisms ◽

Sting Pathway ◽

Mitochondrial Membrane Permeabilization

In the last decade, pieces of evidence for TDP-43-mediated mitochondrial dysfunction in neurodegenerative diseases have accumulated. In patient samples, in vitro and in vivo models have shown mitochondrial accumulation of TDP-43, concomitantly with hallmarks of mitochondrial destabilization, such as increased production of reactive oxygen species (ROS), reduced level of oxidative phosphorylation (OXPHOS), and mitochondrial membrane permeabilization. Incidences of TDP-43-dependent cell death, which depends on mitochondrial DNA (mtDNA) content, is increased upon ageing. However, the molecular pathways behind mitochondrion-dependent cell death in TDP-43 proteinopathies remained unclear. In this review, we discuss the role of TDP-43 in mitochondria, as well as in mitochondrion-dependent cell death. This review includes the recent discovery of the TDP-43-dependent activation of the innate immunity cyclic GMP-AMP synthase/stimulator of interferon genes (cGAS/STING) pathway. Unravelling cell death mechanisms upon TDP-43 accumulation in mitochondria may open up new opportunities in TDP-43 proteinopathy research.

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Cell Death in Coronavirus Infections: Uncovering Its Role during COVID-19

Cells ◽

10.3390/cells10071585 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1585

Author(s):

Annamaria Paolini ◽

Rebecca Borella ◽

Sara De Biasi ◽

Anita Neroni ◽

Marco Mattioli ◽

...

Keyword(s):

Cell Death ◽

Immune Cells ◽

Viral Infections ◽

Virus Entry ◽

Therapeutic Strategies ◽

The Other ◽

Cytokine Storm ◽

Cytokines And Chemokines ◽

Cell Death Mechanisms ◽

The One

Cell death mechanisms are crucial to maintain an appropriate environment for the functionality of healthy cells. However, during viral infections, dysregulation of these processes can be present and can participate in the pathogenetic mechanisms of the disease. In this review, we describe some features of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and some immunopathogenic mechanisms characterizing the present coronavirus disease (COVID-19). Lymphopenia and monocytopenia are important contributors to COVID-19 immunopathogenesis. The fine mechanisms underlying these phenomena are still unknown, and several hypotheses have been raised, some of which assign a role to cell death as far as the reduction of specific types of immune cells is concerned. Thus, we discuss three major pathways such as apoptosis, necroptosis, and pyroptosis, and suggest that all of them likely occur simultaneously in COVID-19 patients. We describe that SARS-CoV-2 can have both a direct and an indirect role in inducing cell death. Indeed, on the one hand, cell death can be caused by the virus entry into cells, on the other, the excessive concentration of cytokines and chemokines, a process that is known as a COVID-19-related cytokine storm, exerts deleterious effects on circulating immune cells. However, the overall knowledge of these mechanisms is still scarce and further studies are needed to delineate new therapeutic strategies.

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Targeting of cancer cell death mechanisms by curcumin; implications to cancer therapy

Basic & Clinical Pharmacology & Toxicology ◽

10.1111/bcpt.13648 ◽

2021 ◽

Author(s):

Chong Yu ◽

Bo Yang ◽

Masoud Najafi

Keyword(s):

Cell Death ◽

Cancer Therapy ◽

Cancer Cell ◽

Cancer Cell Death ◽

Cell Death Mechanisms

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Abstract P419: A Systematic Characterization of Brain Endothelial Cell Death in Intracerebral Hemorrhage

Stroke ◽

10.1161/str.52.suppl_1.p419 ◽

2021 ◽

Vol 52 (Suppl_1) ◽

Author(s):

Maulana Ikhsan ◽

Marietta Zille

Keyword(s):

Cell Death ◽

Intracerebral Hemorrhage ◽

Brain Tissue ◽

Vascular Integrity ◽

Regulated Cell Death ◽

Injury Mechanisms ◽

Endothelial Cell Death ◽

Cell Death Mechanisms ◽

Underlying Mechanisms

Introduction: Intracerebral hemorrhage (ICH) is a type of stroke caused by the loss of vascular integrity leading to bleeding within the brain tissue. Hematoma-derived factors cause secondary injury mechanisms such as cell death days to weeks after the event and in regions distant from the primary insult. Increasing evidence suggests that hemoglobin released by the hematoma is one of the major contributors to neuronal injury in ICH. To date, it is unclear whether brain endothelial cells (EC) are similarly vulnerable to hemolysis products and undergo regulated cell death. Hypothesis: We hypothesized that brain EC undergo multiple, different modes of cell death after ICH and that the underlying mechanisms are different compared to neurons. Methods: We systematically investigated cell death mechanisms in brain EC after exposure to the hemolysis product hemin. We used chemical inhibitors of apoptosis, autophagy, ferroptosis, necroptosis, and parthanatos and assessed biochemical markers of these cell death modes. Results: Brain EC viability was concentration-dependently decreased, starting at higher hemin concentrations than neurons. Treatment of EC with ferroptosis inhibitors protective against hemin toxicity in neurons and against ICH in vivo showed that only N-acetylcysteine and deferoxamine protected brain EC, while ferrostatin-1 and U0126 did not abrogate EC death. The autophagy inhibitor bafilomycin A1 also reduced EC death and hemin increased the expression of the autophagy marker LC3. While inhibitors against apoptosis and parthanatos were not effective, the necroptosis inhibitor GSK872 demonstrated a partial protective effect. Conclusions: Our data suggest that ICH induces different mechanisms of death in EC (ferroptosis and autophagy) compared to neurons (ferroptosis and necroptosis) and may thus warrant a combinatorial therapeutic approach. Further investigations in human and ovine ICH brain tissue are ongoing.

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