Several redox modifications have been described during viral infection, including influenza virus infection, but little is known about glutathionylation and this respiratory virus. Glutathionylation is a reversible, post-translational modification, in which protein cysteine forms transient disulfides with glutathione (GSH), catalyzed by cellular oxidoreductases and in particular by glutaredoxin (Grx). We show here that (i) influenza virus infection induces protein glutathionylation, including that of viral proteins such as hemagglutinin (HA); (ii) Grx1-mediated deglutathionylation is important for the viral life cycle, as its inhibition, either with an inhibitor of its enzymatic activity or by siRNA, decreases viral replication.
View Article and Find Full Text PDFObjective: There is an association between frailty and arterial stiffness. However, arterial stiffness does not uniformly correlate with the spectrum of frailty states. Both oxidative stress and inflammaging contribute to vascular ageing.
View Article and Find Full Text PDFBackground/aims: Community-based assessment and management of chronic liver disease (CLD) in people who are homeless (PWAH) remain poorly described. We aimed to determine prevalence/predictors of CLD in PWAH and assess the performance of non-invasive liver fibrosis and injury markers.
Methods: The Vulnerable Adult LIver Disease (VALID) study provided a "one-stop" liver service based at homeless hostels.
Patients who have experienced a first cerebral ischemic event are at increased risk of recurrent stroke. There is strong evidence that low-level inflammation as measured by high sensitivity C-reactive protein (hs-CRP) is a predictor of further ischemic events. Other mechanisms implicated in the pathogenesis of stroke may play a role in determining the risk of secondary events, including oxidative stress and the adaptive response to it and activation of neuroprotective pathways by hypoxia, for instance through induction of erythropoietin (EPO).
View Article and Find Full Text PDFAn amendment to this paper has been published and can be accessed via the original article.
View Article and Find Full Text PDFAn amendment to this paper has been published and can be accessed via the original article.
View Article and Find Full Text PDFBackground: Vitamin D deficiency increases the risk of developing multiple sclerosis (MS) but it is unclear whether vitamin D supplementation improves the clinical course of MS, and there is uncertainty about the dose and form of vitamin D (D2 or D3) to be used. The mechanisms underlying the effects of vitamin D in MS are not clear. Vitamin D3 increases the rate of differentiation of primary oligodendrocyte precursor cells (OPCs), suggesting that it might help remyelination in addition to modulating the immune response.
View Article and Find Full Text PDFOxidative stress is defined as an imbalance between the levels of reactive oxygen species (ROS) and antioxidant defences. The view of oxidative stress as a cause of cell damage has evolved over the past few decades to a much more nuanced view of the role of oxidative changes in cell physiology. This is no more evident than in the field of immunity, where oxidative changes are now known to regulate many aspects of the immune response, and inflammatory pathways in particular.
View Article and Find Full Text PDFPeroxiredoxin 1 (PRDX1) is an antioxidant enzyme that, when secreted, can act as a proinflammatory signal. Here we studied the regulation of intracellular PRDX1 by lipopolysaccharide (LPS) and interferon-gamma (IFN-γ) in the RAW 264.7 mouse macrophage cell line.
View Article and Find Full Text PDFInflammation is associated with production of reactive oxygen species (ROS) and results in the induction of thioredoxin (TXN) and peroxiredoxins (PRDXs) and activation of nuclear factor-like 2 (Nrf2). In this study we have used the mouse RAW 264.7 macrophage and the human THP-1 monocyte cell line to investigate the pattern of expression of three Nrf2 target genes, PRDX1, TXN reductase (TXNRD1) and heme oxygenase (HMOX1), by activation of different Toll-like receptors (TLRs).
View Article and Find Full Text PDFIntroduction: The ABSORB bioresorbable vascular scaffold (BVS) is associated with greater neointimal proliferation and thrombotic rate than metal stent. The role of inflammatory biomarkers on neointimal proliferation has not been studied in the setting of BVS implantation.
Patients And Methods: Thirty patients had arterial blood sampling before elective percutaneous coronary intervention with the ABSORB BVS and at 9-months follow-up.
Background: The pro-myelinating effects of leukemia inhibitory factor (LIF) and other cytokines of the gp130 family, including oncostatin M (OSM) and ciliary neurotrophic factor (CNTF), have long been known, but controversial results have also been reported. We recently overexpressed erythropoietin receptor (EPOR) in rat central glia-4 (CG4) oligodendrocyte progenitor cells (OPCs) to study the mechanisms mediating the pro-myelinating effects of erythropoietin (EPO). In this study, we investigated the effect of co-treatment with EPO and LIF.
View Article and Find Full Text PDFBackground: Endothelial injury is an early and enduring feature of cardiovascular disease. Inflammation and hypoxia may be responsible for this, and are often associated with the up-regulation of several transcriptional factors that include Hypoxia Inducible Factor-1 (HIF-1). Although it has been reported that HIF-1α is detectable in plasma, it is known to be unstable.
View Article and Find Full Text PDFThe 1998 paper by Wakefield et al., despite subsequent retraction and evidence indicating no causal link between vaccinations and autism, triggered significant parental concern. The aim of this study was to analyze the online information available on this topic.
View Article and Find Full Text PDFThe systemic inflammatory response syndrome (SIRS) is a potentially lethal response triggered by diverse forms of tissue injury and infection. When systemic inflammation is triggered by infection, the term sepsis is used. Understanding how inflammation is mediated and regulated is of enormous medical importance.
View Article and Find Full Text PDFSeveral studies have shown that erythropoietin (EPO) has neuroprotective or neuroreparative actions on diseases of the nervous system and that improves oligodendrocyte (OL) differentiation and myelination and . This study aims at investigating the early molecular mechanisms for the pro-myelinating action of EPO at the gene expression level. For this purpose, we used a differentiating OL precursor cell line, rat central glia-4 cells.
View Article and Find Full Text PDFThe management of hemothorax (spontaneous or, more often, due to thoracic trauma lesions), follows basic tenets well-respected by cardiothoracic surgeons. In most, a non-operative approach is adequate and safe, with a defined group of patients requiring only tube thoracostomy. Only a minority of patients need a surgical intervention due to retained hemothorax, persistent bleeding or incoming complications, as pleural empyema or entrapped lung.
View Article and Find Full Text PDFExtensive chest wall resection and reconstruction are a challenging procedure that requires a multidisciplinary approach, including input from thoracic surgeon, plastic surgeon and oncologist. In particular chest wall neoplastic pathology is associated with high surgical morbidity and can result in full thickness defects hard to reconstruct. The goals of a successful chest wall reconstruction are to restore the chest wall rigidity, preserve pulmonary mechanic and protect the intrathoracic organs minimizing the thoracic deformity.
View Article and Find Full Text PDFGlutathione (GSH), a major cellular antioxidant, is considered an inhibitor of the inflammatory response involving reactive oxygen species (ROS). However, evidence is largely based on experiments with exogenously added antioxidants/reducing agents or pro-oxidants. We show that depleting macrophages of 99% of GSH does not exacerbate the inflammatory gene expression profile in the RAW264 macrophage cell line or increase expression of inflammatory cytokines in response to the toll-like receptor 4 (TLR4) agonist lipopolysaccharide (LPS); only two small patterns of LPS-induced genes were sensitive to GSH depletion.
View Article and Find Full Text PDFThe cytoprotective effects of erythropoietin (EPO) and an EPO-related nonerythropoietic analog, pyroglutamate helix B surface peptide (pHBSP), were investigated in an in vitro model of bovine aortic endothelial cell injury under normoxic (21% O) and hypoxic (1% O) conditions. The potential molecular mechanisms of these effects were also explored. Using a model of endothelial injury (the scratch assay), we found that, under hypoxic conditions, EPO and pHBSP enhanced scratch closure by promoting cell migration and proliferation, but did not show any effect under normoxic conditions.
View Article and Find Full Text PDFErythropoietin (EPO) has both erythropoietic and tissue-protective properties. The EPO analogues carbamylated EPO (CEPO) and pyroglutamate helix B surface peptide (pHBSP) lack the erythropoietic activity of EPO but retain the tissue-protective properties that are mediated by a heterocomplex of EPO receptor (EPOR) and the β common receptor (βCR). We studied the action of EPO and its analogues in a model of wound healing where a bovine aortic endothelial cells (BAECs) monolayer was scratched and the scratch closure was assessed over 24 h under different oxygen concentrations.
View Article and Find Full Text PDFProtein cysteines can form transient disulfides with glutathione (GSH), resulting in the production of glutathionylated proteins, and this process is regarded as a mechanism by which the redox state of the cell can regulate protein function. Most studies on redox regulation of immunity have focused on intracellular proteins. In this study we have used redox proteomics to identify those proteins released in glutathionylated form by macrophages stimulated with lipopolysaccharide (LPS) after pre-loading the cells with biotinylated GSH.
View Article and Find Full Text PDFThe mechanism by which oxidative stress induces inflammation and vice versa is unclear but is of great importance, being apparently linked to many chronic inflammatory diseases. We show here that inflammatory stimuli induce release of oxidized peroxiredoxin-2 (PRDX2), a ubiquitous redox-active intracellular enzyme. Once released, the extracellular PRDX2 acts as a redox-dependent inflammatory mediator, triggering macrophages to produce and release TNF-α.
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