The microRNA-221/-222 cluster balances the antiviral and inflammatory response in viral myocarditis

Abstract Aims Viral myocarditis (VM) is an important cause of heart failure and sudden cardiac death in young healthy adults; it is also an aetiological precursor of dilated cardiomyopathy. We explored the role of the miR-221/-222 family that is up-regulated in VM. Methods and results Here, we show that microRNA-221 (miR-221) and miR-222 levels are significantly elevated during acute VM caused by Coxsackievirus B3 (CVB3). Both miRs are expressed by different cardiac cells and by infiltrating inflammatory cells, but their up-regulation upon myocarditis is mostly exclusive for the cardiomyocyte. Systemic inhibition of miR-221/-222 in mice increased cardiac viral load, prolonged the viraemic state, and strongly aggravated cardiac injury and inflammation. Similarly, in vitro, overexpression of miR-221 and miR-222 inhibited enteroviral replication, whereas knockdown of this miR-cluster augmented viral replication. We identified and confirmed a number of miR-221/-222 targets that co-orchestrate the increased viral replication and inflammation, including ETS1/2, IRF2, BCL2L11, TOX, BMF, and CXCL12. In vitro inhibition of IRF2, TOX, or CXCL12 in cardiomyocytes significantly dampened their inflammatory response to CVB3 infection, confirming the functionality of these targets in VM and highlighting the importance of miR-221/-222 as regulators of the cardiac response to VM. Conclusions The miR-221/-222 cluster orchestrates the antiviral and inflammatory immune response to viral infection of the heart. Its inhibition increases viral load, inflammation, and overall cardiac injury upon VM.

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Assessment of the biochemical effects of percutaneous exposure of sulphur mustard in an in vitro human skin system

Human & Experimental Toxicology ◽

10.1177/096032719601500309 ◽

1996 ◽

Vol 15 (3) ◽

pp. 237-244 ◽

Cited By ~ 24

Author(s):

CD Lindsay ◽

P. Rice

Keyword(s):

Inflammatory Response ◽

Human Skin ◽

Serine Proteases ◽

Inflammatory Cells ◽

Chemical Warfare Agent ◽

Skin Damage ◽

Sulphur Mustard ◽

Nuclear Pyknosis ◽

Skin Explants

1 Sulphur mustard (HD) is a potent chemical warfare agent which causes incapacitating blisters on human skin. There is no specific pretreatment nor therapy against this agent and the mechanism of dermo-epidermal cleavage is unclear. The aim of this study was to use a human skin explant system to determine the consequences of percuta neous exposure to HD. 2 Increased activities of serine proteases associated with blistering disorders in humans were detected from human skin explants after exposure to HD. The most consistent response and the highest protease activities measured were found for trypsin. This class of enzyme is therefore implicated in the dermo-epidermal separation which is associated with blistering in humans following exposure to HD. 3 An inflammatory response was observed in the skin explants exposed to HD. At low doses of HD it was characterised by the presence of neutrophils in the papillary dermis, culminating in the infiltration of the epidermis by these inflammatory cells at higher concen trations of HD. A variety of other histopathological changes in the explants was found such as focal dermo- epidermal separation, nuclear pyknosis and perinuclear vacuolation. 4 The study indicates that full thickness human skin explants can be used to investigate various aspects of the possible pathogenesis of HD-induced skin damage, in cluding the associated inflammatory response.

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Thyroxine Affects Lipopolysaccharide-Induced Macrophage Differentiation and Myocardial Cell Apoptosis via the NF-κB p65 Pathway Both In Vitro and In Vivo

Mediators of Inflammation ◽

10.1155/2019/2098972 ◽

2019 ◽

Vol 2019 ◽

pp. 1-10 ◽

Cited By ~ 4

Author(s):

Shan Zhu ◽

Yuan Wang ◽

Hongtao Liu ◽

Wen Wei ◽

Yi Tu ◽

...

Keyword(s):

Inflammatory Response ◽

Cardiac Dysfunction ◽

Cell Apoptosis ◽

Cardiac Injury ◽

Myocardial Cell ◽

M2 Macrophage ◽

Mrna Levels ◽

Cytokine Mrna ◽

M1 Macrophage

Background. Numerous studies have demonstrated that the inflammatory response is involved in the progression of lipopolysaccharide- (LPS-) induced myocardial cell apoptosis. Accumulating evidence has shown that thyroxine participates in diseases by downregulating the inflammatory response. This study aimed at investigating whether thyroxine alleviates LPS-induced myocardial cell apoptosis. Methods. Bone marrow-derived macrophages (Mø) were treated with LPS and thyroxine, and Mø differentiation and Mø-related cytokine expression were measured. The effect of Mø differentiation on mouse cardiomyocyte (MCM) apoptosis was also detected in vitro. In addition, C57BL/6 mice underwent thyroidectomy and were treated with LPS 35 days later; subsequently, Mø differentiation and myocardial cell apoptosis in hearts were analyzed. To determine whether the nuclear factor-kappa B (NF-κB) p65 pathway mediates the effect of thyroxine on Mø differentiation and myocardial cell apoptosis, the specific NF-κB p65 pathway inhibitor JSH-23 was administered to mice that underwent a thyroidectomy. Results. Levothyroxine treatment significantly reduced the activation of the NF-κB p65 pathway, decreased M1 macrophage (Mø1) differentiation and Mø1-related cytokine mRNA levels in LPS-treated Mø, and increased M2 macrophage (Mø2) differentiation and Mø2-related cytokine mRNA expression. The protective effects of levothyroxine on MCM apoptosis mediated by LPS-treated Mø were alleviated by JSH-23. In mice, thyroidectomy aggravated LPS-induced cardiac injury and cardiac dysfunction, further promoted NF-κB p65 activation, and increased cardiac Mø1 expression and myocardial cell apoptosis but decreased cardiac Mø2 expression. JSH-23 treatment significantly ameliorated the thyroidectomy-induced increases in myocardial cell apoptosis and Mø differentiation. Conclusions. Thyroxine alleviated the Mø1/Mø2 imbalance, reduced the inflammatory response, decreased myocardial cell apoptosis, and protected against cardiac injury and cardiac dysfunction in LPS-treated mice. Thyroxine may be a novel therapeutic strategy to prevent and treat LPS-induced cardiac injury.

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In Vitro Model Systems of Coxsackievirus B3-Induced Myocarditis: Comparison of Commonly Used Cell Lines and Characterization of CVB3-Infected iCell® Cardiomyocytes

Viruses ◽

10.3390/v13091835 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1835

Author(s):

Lisa Kraft ◽

Martina Sauter ◽

Guiscard Seebohm ◽

Karin Klingel

Keyword(s):

Cell Death ◽

Viral Load ◽

Cell Lines ◽

Hela Cells ◽

Coxsackievirus B3 ◽

Model System ◽

Model Systems ◽

H9c2 Cells ◽

Cvb3 Infection

Coxsackievirus B3 (CVB3) belongs to the enteroviruses, which are a well-known cause of acute and chronic myocarditis, primarily infecting cardiac myocytes. As primary human cardiomyocytes are difficult to obtain, viral myocarditis is quite frequently studied in vitro in different non-cardiac and cardiac-like cell lines. Recently, cardiomyocytes that have been differentiated from human-induced pluripotent stem cells have been described as a new model system to study CVB3 infection. Here, we compared iCell® Cardiomyocytes with other cell lines that are commonly used to study CVB3 infection regarding their susceptibility and patterns of infection and the mode of cell death. iCell® Cardiomyocytes, HeLa cells, HL-1 cells and H9c2 cells were infected with CVB3 (Nancy strain). The viral load, CVB3 RNA genome localization, VP1 expression (including the intracellular localization), cellular morphology and the expression of cell death markers were compared. The various cell lines clearly differed in their permissiveness to CVB3 infection, patterns of infection, viral load, and mode of cell death. When studying the mode of cell death of CVB3-infected iCell® Cardiomyocytes in more detail, especially regarding the necroptosis key players RIPK1 and RIPK3, we found that RIPK1 is cleaved during CVB3 infection. iCell® Cardiomyocytes represent well the natural host of CVB3 in the heart and are thus the most appropriate model system to study molecular mechanisms of CVB3-induced myocarditis in vitro. Doubts are raised about the suitability of commonly used cell lines such as HeLa cells, HL-1 cells and H9c2 cells to evaluate molecular pathways and processes occurring in vivo in enteroviral myocarditis.

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S100A6 Promotes Inflammation and Infiltration of Mononuclear/Macrophages via the p-P38 and p-JNK Pathways in Acute Liver Injury

10.21203/rs.3.rs-1161048/v1 ◽

2021 ◽

Author(s):

He Tong ◽

Li Wang ◽

Kefan Zhang ◽

Jing Shi ◽

yongshuai Wu ◽

...

Keyword(s):

Liver Injury ◽

Inflammatory Response ◽

Inflammatory Responses ◽

Acute Liver Injury ◽

S100 Protein ◽

Inflammatory Cells ◽

Liver Cells ◽

Danger Signal ◽

Tnf Α

Abstract BackgroundThe phagocytic S100 protein, which mediates inflammatory responses and recruits inflammatory cells to sites of tissue damage, has long been known to be expressed in cells of myeloid origin. S100A6 belongs to the A group of the S100 protein family of Ca2+-binding proteins. Currently, the mechanism by which S100A6 mediates the inflammatory response and recruits inflammatory cells to the tissue injury site is unknown.MethodsA mouse model of carbon tetrachloride (CCl4)-induced acute liver injury (ALI) was established, and the transcriptomes of postinjury 2d and 5d liver tissues were sequenced. Enzyme-linked immunosorbent assay was used to determine the expression of inflammatory factors (TNF-α, IL-1β, IL-6, and IL-8) in the supernatant of the liver. Immunohistochemical analysis confirmed the expression of S100A6 in the liver cells. In vitro experiments proved the pro-inflammatory function of S100A6, and western blotting (WB) showed that the pathways were activated. The transwell experiment showed the infiltration of mononuclear/macrophages.ResultsWe found that S100A6 is highly expressed in liver cells during the most severe period of ALI, suggesting that it acts as an endogenous danger signal and has a pro-inflammatory function. In vitro, the mouse S100A6 recombinant protein was used to stimulate liver Kupffer cells to promote the secretion of TNF-α, IL-1β, IL-6, and IL-8. Further mechanistic experiments revealed that S100A6 acts as an endogenous danger signal to activate p-P38 and p-JNK downstream of the TLR4 and P65 pathways. Similarly, transcriptome data showed that S100A6 can activate the inflammatory response in Kuffer cells. WB revealed that S100A6 had no significant effect on cell apoptosis. To continue to explore the mechanism of monocyte/macrophage infiltration, we found that TNF-α stimulates liver cells as the main source of CCL2. TNF-α can initiate the p-P38 and p-JNK pathways of liver cells to produce CCL2, thereby recruiting the infiltration of mononuclear/macrophages. ConclusionsTaken together, S100A6 is an endogenous danger signal that mediates inflammatory responses and recruits inflammatory cells to sites of tissue damage.

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Review of the use of nasal and oral antiseptics during a global pandemic

Future Microbiology ◽

10.2217/fmb-2020-0286 ◽

2021 ◽

Vol 16 (2) ◽

pp. 119-130

Author(s):

Christopher Stathis ◽

Nikolas Victoria ◽

Kristin Loomis ◽

Shaun A Nguyen ◽

Maren Eggers ◽

...

Keyword(s):

Clinical Trials ◽

Viral Load ◽

Viral Replication ◽

Hypertonic Saline ◽

Hypochlorous Acid ◽

Povidone Iodine ◽

Nasal Sprays ◽

Early Stages ◽

Global Pandemic

A review of nasal sprays and gargles with antiviral properties suggests that a number of commonly used antiseptics including povidone-iodine, Listerine®, iota-carrageenan and chlorhexidine should be studied in clinical trials to mitigate both the progression and transmission of SARS-CoV-2. Several of these antiseptics have demonstrated the ability to cut the viral load of SARS-CoV-2 by 3–4 log10 in 15–30 s in vitro. In addition, hypertonic saline targets viral replication by increasing hypochlorous acid inside the cell. A number of clinical trials are in process to study these interventions both for prevention of transmission, prophylaxis after exposure, and to diminish progression by reduction of viral load in the early stages of infection.

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Intrinsic Abnormalities of Cystic Fibrosis Airway Connective Tissue Revealed by an In Vitro 3D Stromal Model

Cells ◽

10.3390/cells9061371 ◽

2020 ◽

Vol 9 (6) ◽

pp. 1371

Author(s):

Claudia Mazio ◽

Laura S. Scognamiglio ◽

Rossella De Cegli ◽

Luis J. V. Galietta ◽

Diego Di Bernardo ◽

...

Keyword(s):

Cystic Fibrosis ◽

Inflammatory Response ◽

Bacterial Infections ◽

Inflammatory Cells ◽

Lung Model ◽

Lung Dysfunction ◽

Novel Therapeutic Strategies ◽

And Function

Cystic fibrosis is characterized by lung dysfunction involving mucus hypersecretion, bacterial infections, and inflammatory response. Inflammation triggers pro-fibrotic signals that compromise lung structure and function. At present, several in vitro cystic fibrosis models have been developed to study epithelial dysfunction but none of these focuses on stromal alterations. Here we show a new cystic fibrosis 3D stromal lung model made up of primary fibroblasts embedded in their own extracellular matrix and investigate its morphological and transcriptomic features. Cystic fibrosis fibroblasts showed a high proliferation rate and produced an abundant and chaotic matrix with increased protein content and elastic modulus. More interesting, they had enhanced pro-fibrotic markers and genes involved in epithelial function and inflammatory response. In conclusion, our study reveals that cystic fibrosis fibroblasts maintain in vitro an activated pro-fibrotic state. This abnormality may play in vivo a role in the modulation of epithelial and inflammatory cell behavior and lung remodeling. We argue that the proposed bioengineered model may provide new insights on epithelial/stromal/inflammatory cells crosstalk in cystic fibrosis, paving the way for novel therapeutic strategies.

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Rosuvastatin corrects oxidative stress and inflammation induced by LPS to attenuate cardiac injury by inhibiting the NLRP3/TLR4 pathway

Canadian Journal of Physiology and Pharmacology ◽

10.1139/cjpp-2020-0321 ◽

2021 ◽

Author(s):

Guocheng Ren ◽

Qiujie Zhou ◽

Meili Lu ◽

Hongxin Wang

Keyword(s):

Oxidative Stress ◽

Inflammatory Response ◽

Cardiac Injury ◽

H9c2 Cells ◽

Sod Activity ◽

Lps Challenge ◽

Pathway Activation ◽

Underlying Mechanisms

The aim of the current study was to evaluate whether rosuvastatin was effective in attenuating cardiac injury in lipopolysaccharide(LPS)-challenged mice and H9C2 cells and identify the underlying mechanisms, focusing on the NLRP3/TLR4 pathway. Cardiac injury, cardiac function, apoptosis, oxidative stress, inflammatory response and the NLRP3/TLR4 pathway were evaluated in both in vivo and in vitro studies. LPS-induced cardiomyocytes injury was markedly attenuated by rosuvastatin treatment. Apoptosis was clearly ameliorated in myocardial tissue and H9C2 cells cotreated with rosuvastatin. In addition, excessive oxidative stress was present, as indicated by increases in MDA content, NADPH activity and ROS production and decreased SOD activity after LPS challenge. Rosuvastatin improved all the indicators of oxidative stress, with a similar effect to NAC(ROS scavenger). Notably, LPS-exposed H9C2 cells and mice showed significant NLRP3 and TLR4/NF-κB pathway activation. Administration of rosuvastatin reduced the increases in expression of NLRP3, ASC, pro-caspase-1, TLR4, and p65 and decreased the contents of TNF-α, IL-1β, IL-18 and IL-6, with a similar effect as MCC950 (NLRP3 inhibitor). In conclusion, inhibition of the inflammatory response and oxidative stress contributes to cardioprotection of rosuvastatin on cardiac injury induced by LPS, and the effect of rosuvastatin was achieved by inactivation of the NF-κB/NLRP3 pathway

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Abstract 509: Oxytocin Mediates Neuroendocrine Reprogramming of the Epicardium in Heart Regeneration

Circulation Research ◽

10.1161/res.127.suppl_1.509 ◽

2020 ◽

Vol 127 (Suppl_1) ◽

Author(s):

Aaron H Wasserman ◽

Amanda R Huang ◽

Aitor Aguirre

Keyword(s):

Stem Cell ◽

Epithelial Mesenchymal Transition ◽

Cardiac Injury ◽

The United States ◽

Cardiac Cells ◽

Heart Regeneration ◽

Mesenchymal Transition ◽

Epicardial Cells ◽

Cell Counts

Cardiovascular disease (CVD) is the leading cause of mortality both in the United States and worldwide. CVD often results in the massive loss of contractile cardiac cells and tissue. Critical work in the last two decades demonstrates that lost cells can be partially replenished by the epicardium, the outermost mesothelial layer of the heart. Upon cardiac injury, mature epicardial cells activate and undergo epithelial-mesenchymal transition (EMT) to form epicardium-derived progenitor cells (EPDCs), which are a type of multipotent stem cell that can differentiate into several important cardiac lineages, including cardiomyocytes and vascular cells. This process alone is insufficient for significant regeneration, but its efficiency can be improved by priming with specific factors (e.g., thymosin beta-4). Our group has recently discovered evidence that oxytocin (OT), a hypothalamic neuroendocrine peptide, induces a pro-regenerative phenotype in vitro in human induced pluripotent stem cell (iPSC) derived epicardial cells. We hypothesize that upon cardiac injury, oxytocin is released into the bloodstream, causing activation of the epicardium and mobilization of EPDCs to elicit regeneration of damaged tissue and restoration of function. Here, we show that we can differentiate mature, high-quality epicardial cells from iPSCs and that Ki67 levels and cell counts increase after three days of OT exposure. In addition, the peptide alters gene expression levels of several epithelial, mesenchymal, and EMT markers, indicating a transition to a dedifferentiated gene profile characteristic of EPDCs. Finally, when OT is administered intravenously to mice, it accelerates healing from cardiac injury by inducing epicardial activation. Future studies will aim to further reveal the physiological contribution of OT to heart regeneration in vivo and determine its molecular mechanism of action. Our findings have the potential to uncover a novel mechanism of neuroendocrine reprogramming of the injured heart and yield significant translational advances in the treatment of CVD.

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Effect of Prolonged Fluconazole Treatment on Candida albicans in Diffusion Chambers Implanted into Mice

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.46.10.3175-3179.2002 ◽

2002 ◽

Vol 46 (10) ◽

pp. 3175-3179

Author(s):

Peter G. Sohnle ◽

Beth L. Hahn

Keyword(s):

Candida Albicans ◽

Inflammatory Response ◽

Inflammatory Cells ◽

Model System ◽

Antifungal Drugs ◽

Yeast Cells ◽

In Vitro Susceptibility ◽

Bonferroni Test

ABSTRACT Fluconazole is an azole agent with primarily fungistatic activity in standard in vitro susceptibility tests. The present study was undertaken to develop a diffusion chamber model system in mice in order to study the in vivo effects of prolonged fluconazole treatment on Candida albicans. Chambers containing 100 C. albicans yeast cells were implanted subcutaneously on the flanks of C57BL/6 mice and were then retrieved 6 or 14 weeks later (after fluconazole treatment for 4 or 12 weeks, respectively). Leukocyte counts demonstrated that implantation of the chambers did elicit an inflammatory response but that only small numbers of inflammatory cells were able to enter the chamber interior. Treatment with fluconazole at 10 mg/kg of body weight/day for 12 weeks not only reduced the numbers of viable organisms within the chambers compared to those in untreated mice (mean ± standard deviation of log10 CFU of 0.7 ± 1.2 versus 2.3 ± 2.0; P < 0.001 by the Bonferroni test) but also increased the numbers of chambers that became sterile over the treatment period (14 of 16 versus 6 of 19; P = 0.0009 by the chi-square test). However, treatment for only 4 weeks had minimal effects on the numbers of chamber CFU, and none of the chambers became sterile during this period. Distribution of retrieved organisms between interior fluid and the chamber filters was approximately equal in all the treatment groups. This model system appears to be useful for evaluating the effects of antifungal drugs over prolonged periods in vivo. Its use in the present study demonstrates that fluconazole can increase the rate of sterilization of C. albicans foci that are protected from the host's inflammatory response.

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Modulation of Immune Complex–induced Inflammation In Vivo by the Coordinate Expression of Activation and Inhibitory Fc Receptors

Journal of Experimental Medicine ◽

10.1084/jem.189.1.179 ◽

1999 ◽

Vol 189 (1) ◽

pp. 179-186 ◽

Cited By ~ 295

Author(s):

Raphael Clynes ◽

Jay S. Maizes ◽

Rodolphe Guinamard ◽

Masao Ono ◽

Toshiyuki Takai ◽

...

Keyword(s):

Inflammatory Response ◽

Immune Complexes ◽

Inflammatory Responses ◽

Fc Receptors ◽

Inflammatory Cells ◽

Neutrophil Infiltration ◽

Calcium Flux ◽

Deficient Mice

Autoantibodies and immune complexes are major pathogenic factors in autoimmune injury, responsible for initiation of the inflammatory cascade and its resulting tissue damage. This activation results from the interaction of immunoglobulin (Ig)G Fc receptors containing an activation motif (ITAM) with immune complexes (ICs) and cytotoxic autoantibodies which initiates and propagates an inflammatory response. In vitro, this pathway can be interrupted by coligation to FcγRIIB, an IgG Fc receptor containing an inhibitory motif (ITIM). In this report, we describe the in vivo consequences of FcγRII deficiency in the inflammatory response using a mouse model of IC alveolitis. At subthreshold concentrations of ICs that fail to elicit inflammatory responses in wild-type mice, FcγRII-deficient mice developed robust inflammatory responses characterized by increased hemorrhage, edema, and neutrophil infiltration. Bronchoalveolar fluids from FcγRII−/− stimulated mice contain higher levels of tumor necrosis factor and chemotactic activity, suggesting that FcγRII deficiency lowers the threshold of IC stimulation of resident cells such as the alveolar macrophage. In contrast, complement- and complement receptor–deficient mice develop normal inflammatory responses to suprathreshold levels of ICs, while FcRγ−/− mice are completely protected from inflammatory injury. An inhibitory role for FcγRII on macrophages is demonstrated by analysis of FcγRII−/− macrophages which show greater phagocytic and calcium flux responses upon FcγRIII engagement. These data reveal contrasting roles for the cellular receptors for IgG on inflammatory cells, providing a regulatory mechanism for setting thresholds for IC sensitivity based on the ratio of ITIM to ITAM FcγR expression. Exploiting the FcγRII inhibitory pathway could thus provide a new therapeutic approach for modulating antibody-triggered inflammation.

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