Potential Role of Antioxidant and Anti-Inflammatory Therapies to Prevent Severe SARS-Cov-2 Complications

The coronavirus disease 2019 (COVID-19) pandemic is caused by a novel severe acute respiratory syndrome (SARS)-like coronavirus (SARS-CoV-2). Here, we review the molecular pathogenesis of SARS-CoV-2 and its relationship with oxidative stress (OS) and inflammation. Furthermore, we analyze the potential role of antioxidant and anti-inflammatory therapies to prevent severe complications. OS has a potential key role in the COVID-19 pathogenesis by triggering the NOD-like receptor family pyrin domain containing 3 inflammasome and nuclear factor-kB (NF-kB). While exposure to many pro-oxidants usually induces nuclear factor erythroid 2 p45-related factor2 (NRF2) activation and upregulation of antioxidant related elements expression, respiratory viral infections often inhibit NRF2 and/or activate NF-kB pathways, resulting in inflammation and oxidative injury. Hence, the use of radical scavengers like N-acetylcysteine and vitamin C, as well as of steroids and inflammasome inhibitors, has been proposed. The NRF2 pathway has been shown to be suppressed in severe SARS-CoV-2 patients. Pharmacological NRF2 inducers have been reported to inhibit SARS-CoV-2 replication, the inflammatory response, and transmembrane protease serine 2 activation, which for the entry of SARS-CoV-2 into the host cells through the angiotensin converting enzyme 2 receptor. Thus, NRF2 activation may represent a potential path out of the woods in COVID-19 pandemic

Is Ferroptosis a Key Component of the Process Leading to Multiorgan Damage in COVID-19?

Even though COVID-19 is mostly well-known for affecting respiratory pathology, it can also result in several extrapulmonary manifestations, leading to multiorgan damage. A recent reported case of SARS-CoV-2 myocarditis with cardiogenic shock showed a signature of myocardial and kidney ferroptosis, a novel, iron-dependent programmed cell death. The term ferroptosis was coined in the last decade to describe the form of cell death induced by the small molecule erastin. As a specific inducer of ferroptosis, erastin inhibits cystine-glutamate antiporter system Xc-, blocking transportation into the cytoplasm of cystine, a precursor of glutathione (GSH) in exchange with glutamate and the consequent malfunction of GPX4. Ferroptosis is also promoted by intracellular iron overload and by the iron-dependent accumulation of polyunsaturated fatty acids (PUFA)- derived lipid peroxides. Since depletion of GSH, inactivation of GPX4, altered iron metabolism, and upregulation of PUFA peroxidation by reactive oxygen species are peculiar signs of COVID-19, there is the possibility that SARS-CoV-2 may trigger ferroptosis in the cells of multiple organs, thus contributing to multiorgan damage. Here, we review the molecular mechanisms of ferroptosis and its possible relationship with SARS-CoV-2 infection and multiorgan damage. Finally, we analyze the potential interventions that may combat ferroptosis and, therefore, reduce multiorgan damage

Intracellular Polyphenol Wine Metabolites Oppose Oxidative Stress and Upregulate Nrf2/ARE Pathway

Moderate wine consumption has been associated with several benefits to human health due to its high polyphenol content. In this study, we investigated whether polyphenols contained in a particular red wine, rich in polyphenols, can pass the cell membrane and switch the oxidant/antioxidant balance toward an antioxidant pattern of THP-1 cells and human cardiomyocytes through a gene regulatory system. First, we identified which metabolite polyphenols present in red wine extract cross cell membranes and may be responsible for antioxidant effects. The results showed that the wine metabolites in treated cells belonged mainly to stilbenes, flavan-3-ols derivatives, and flavonoids. Other metabolites present in cells were not typical wine metabolites. Then, we found that red wine extract dose-dependently lowered reactive oxygen species (ROS) induced by tert-butyl hydroperoxide (TBHP) up to 50 +/- 7% in both cell lines (p < 0.01). Furthermore, wine extract increased nuclear Nrf2 of about 35 +/- 5% in both cell lines (p < 0.01) and counteracted its reduction induced by TBHP (p < 0.01). The rise in Nrf2 was paralleled by the increase in hemeoxygenase-1 and glutamate-cysteine ligase catalytic subunit gene expression (both mRNA and protein) (p < 0.01). These results could help explain the healthful activity of wine polyphenols within cells

Comparison between the diagnostic accuracy of clinico-pathological and molecular tests for feline infectious peritonitis (FIP)

The aim of this study was to compare the diagnostic accuracy for feline infectious peritonitis (FIP) of conventional clinic-pathological tests with that of molecular tests such as routine PCR and PCR followed by the sequencing of the Spike (S) gene. Blood, effusion and tissues specimens were collected from 21 FIP suspected cats. In vivo examination consisted of CBC, serum protein electrophoresis, AGP measurement, cytological and biochemical examination and the evaluation of the ΔTNC on effusions, and of molecular tests such the screening PCR (target: 3’UTR region) and the PCR directed towards the S gene followed by the amplification products sequencing in order to detect the aminoacidic substitution recently considered diagnostic for FIP1. These molecular techniques were applied to tissues collected during necropsy, which also allowed forming an FIP group (13 cats) and a non-FIP group (5 cats) based on histology and immunohistochemistry. The best test on tissues was immunohistochemistry (sens: 92.3%; spec: 100%), while the screening PCR suffered of low specificity (spec: 33.3%) and the S gene sequencing showed low sensitivity (sens: 69.2%).On effusions, the best tests resulted screening PCR and cytology (sens and spec: 100%) in comparison with the ΔTNC measurement (sens: 85.7 %; spec: 100%) and the S gene sequencing (sens: 42.8%; spec: 100%).On blood, the best test resulted AGP measurement (sens: 81.8%; spec: 100%), while serum protein electrophoresis showed a surprisingly low sensitivity (sens: 41.7%). Screening PCR (sens: 55.6%; spec: 100%) and S gene sequencing (sens: 33.3%; spec: 100%) proved again low accuracy.

Ezetimibe prevents ischemia/reperfusion-induced oxidative stress and up-regulates Nrf2/ARE and UPR signaling pathways

BACKGROUND: While reperfusion is crucial for survival after an episode of ischemia, it also causes oxidative stress. Nuclear factor-E2-related factor 2 (Nrf2) and unfolded protein response (UPR) are protective against oxidative stress and endoplasmic reticulum (ER) stress. Ezetimibe, a cholesterol absorption inhibitor, has been shown to activate the AMP-activated protein kinase (AMPK)/Nrf2 pathway. In this study we evaluated whether Ezetimibe affects oxidative stress and Nrf2 and UPR gene expression in cellular models of ischemia-reperfusion (IR). METHODS: Cultured cells were subjected to simulated IR with or without Ezetimibe. RESULTS: IR significantly increased reactive oxygen species (ROS) production and the percentage of apoptotic cells without the up-regulation of Nrf2, of the related antioxidant response element (ARE) gene expression or of the pro-survival UPR activating transcription factor 6 (ATF6) gene, whereas it significantly increased the pro-apoptotic CCAAT-enhancer-binding protein homologous protein (CHOP). Ezetimibe significantly decreased the cellular ROS formation and apoptosis induced by IR. These effects were paralleled by the up-regulation of Nrf2/ARE and ATF6 gene expression and by a down-regulation of CHOP. We also found that Nrf2 activation was dependent on AMPK, since Compound C, a pan inhibitor of p-AMPK, blunted the activation of Nrf2. CONCLUSIONS: Ezetimibe counteracts IR-induced oxidative stress and induces Nrf2 and UPR pathway activation

Effects of Nebivolol on Endothelial Gene Expression during Oxidative Stress in Human Umbilical Vein Endothelial Cells

The endothelium plays a key role in the development of atherogenesis and its inflammatory and proliferative status influences the progression of atherosclerosis. The aim of this study is to compare the effects of two beta blockers such as nebivolol and atenolol on gene expression in human umbilical vein endothelial cells (HUVECs) following an oxidant stimulus. HUVECs were incubated with nebivolol or atenolol (10 micromol/L) for 24 hours and oxidative stress was induced by the addition of oxidized (ox)-LDL. Ox-LDL upregulated adhesion molecules (ICAM-1, ICAM-2, ICAM-3, E-selectin, and P-selectin); proteins linked to inflammation (IL-6 and TNFalpha), thrombotic state (tissue factor, PAI-1 and uPA), hypertension such as endothelin-1 (ET-1), and vascular remodeling such as metalloproteinases (MMP-2, MMP-9) and protease inhibitor (TIMP-1). The exposure of HUVECs to nebivolol, but not to atenolol, reduced these genes upregulated by oxidative stress both in terms of protein and RNA expression. The known antioxidant properties of the third generation beta blocker nebivolol seem to account to the observed differences seen when compared to atenolol and support the specific potential protective role of this beta blocker on the expression of a number of genes involved in the initiation and progression of atherosclerosis

New Insights into the Role of Ferroptosis in Cardiovascular Diseases

Cardiovascular diseases (CVDs) are the principal cause of disease burden and death worldwide. Ferroptosis is a new formof regulated cell deathmainly characterized by altered ironmetabolism, increased polyunsaturated fatty acid peroxidation by reactive oxygen species, depletion of glutathione and inactivation of glutathione peroxidase 4. Recently, a series of studies have indicated that ferroptosis is involved in the death of cardiac and vascular cells and has a key impact on the mechanisms leading to CVDs such as ischemic heart disease, ischemia/reperfusion injury, cardiomyopathies, and heart failure. In this article, we reviewed the molecular mechanism of ferroptosis and the current understanding of the pathophysiological role of ferroptosis in ischemic heart disease and in some cardiomyopathies. Moreover, the comprehension of the machinery governing ferroptosis in vascular cells and cardiomyocytes may provide new insights into preventive and therapeutic strategies in CVDs

Nuclear factor kappa B in patients with a history of unstable angina: case re-opened

This study aims at assessing NF-kB activity in unstable angina (UA) patients free of symptoms after a 1 year follow-u

Fast method for skeletal tissue gene expression analysis

open9Several chronic diseases have been associated with bone alteration in the last few years. Despite the wealth of information provided by the analysis of the transcriptome in affected tissues, only a limited number of studies evaluated gene expression in bone tissue due to the difficulty to obtain high quality RNA. Therefore, skeletal pathologies have been often associated to a defective maturation process that occurs during recruitment of progenitor stem cells. In order to explore the possibility of analysing the gene expression during osteogenic differentiation in skeletal tissue, a single-step method to extract well-preserved RNA from bone specimens was performed. A comparison between this technique and a traditional method was made by analysing the quality and yield of RNA obtained. In addition, RNAs were assayed by reverse transcription-quantitative polymerase chain reaction to analyse the expression levels of the bone genes associated with the differentiation process in a mouse model. The present data showed that good quality RNA can be obtained from bone tissue by a simple single-step method allowing the expression analysis of the genes encoded by skeletal tissue. In conclusion, the present study allows the possibility to easily obtain good quality RNA from bone tissue that is suitable for gene expression studies of bone diseases.openDalle Carbonare, Luca; Vilei, Maria Teresa; Stranieri, Chiara; Innamorati, Giulio; Rosato, Antonio; Boldrin, Elisa; Sella, Stefania; Giannini, Sandro; Valenti, Maria TeresaDALLE CARBONARE, LUCA GIUSEPPE; Vilei, MARIA TERESA; Stranieri, Chiara; Innamorati, Giulio; Rosato, Antonio; Boldrin, Elisa; Sella, Stefania; Giannini, Sandro; Valenti, Maria Teres

Nrf2 expression is increased in peripheral blood mononuclear cells derived from mild\u2013moderate ex-smoker COPD patients with persistent oxidative stress

Inadequacy of antioxidant nuclear factor-E2-related factor 2 (Nrf2) and endoplasmic reticulum stress-mediated unfolded protein response has been implicated in severe chronic obstructive pulmonary disease (COPD) and cigarette smoking-induced emphysema. As evidence suggests that the ability to upregulate Nrf2 expression may influence the progression of COPD and no data exist up to now in ex-smokers with mild\u2013moderate COPD, this study was first aimed to evaluate Nrf2 and unfolded protein response expression in peripheral blood mononuclear cells (PBMC) of mild\u2013moderate ex-smokers with COPD compared to smoking habit-matched non-COPD subjects. Then, we tested whether oxidative stress persists after cigarette smoking cessation and whether the concentrations of oxidized phospholipids (oxidation products of the phospholipid 1-palmitoyl-2-arachidonyl-sn-glycero-3-phosphorylcholine [oxPAPC]) in the PBMC of the same subjects may have a causative role in determining the upregulation of Nrf2. The expression (mRNA and protein) of Nrf2 and of its related gene heme oxygenase-1 was significantly increased in COPD group without differences in the unfolded protein response. Plasma malondialdehyde, the circulating marker of oxidative stress, and oxPAPC in PBMC were significantly higher in COPD than in non-COPD subjects. The fact that the expression of p47phox, a subunit of NADPH oxidase, was increased in PBMC of COPD patients and that it was directly correlated with oxPAPC may indicate that oxPAPC may be one of the determinants of oxidative stress-induced Nrf2 upregulation. Finally, we also demonstrated that lung function inversely correlated with plasma malondialdehyde and with Nrf2 and heme oxygenase-1 mRNA expression in all subjects. Our results indicate that mild\u2013moderate ex-smokers with COPD may be able to counteract oxidative stress by increasing the expression of Nrf2/antioxidant-response elements. Because Nrf2 failure significantly contributes to the development of COPD, our findings suggest that the possibility to prevent Nrf2 reduction may open a new scenario in helping to prevent the oxidative stress-associated lung function decline