Lung injury associated with an e-cigarette (vaping) use during the COVID-19 pandemic

In recent years, the excessive use of electronic cigarettes (e-cigarettes), and vaping, as a re-placement for traditional tobacco cigarettes, have highlighted potential health risks for users. One such risk is the development of "electronic cigarette (vaping) product use-associated lung injury" (EVALI). This type of lung injury has an unclear cause that may be related to the various components found in e-cigarette fluids. The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection (coronavirus disease . 2019 or COVID-19) may worsen EVALI symptoms in individuals with both conditions. This could be due to the increased oxidative stress and inflammation caused by e-cigarette use, as re-search shows increased levels of reactive oxygen species (ROS) and decreased glutathione. In this paper, we present two critical cases of COVID-19 patients with a history of chronic e-cigarette smoking and describe their clinical progression during hospitalization. The findings suggest that their prolonged use of e-cigarettes may have sig-nificantly impacted the severity of the disease.Copyright © 2023, The Indonesian Foundation of Critical Care Medicine. All rights reserved.

Functional Role of Natural Antioxidants in Controlling Oxidative Stress Associated with SARS-CoV-2 Infection

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a pathogenic coronavirus that emerged in late 2019, resulting in coronavirus disease (COVID-19). COVID-19 can be potentially fatal among a certain group of patients. Older age and underlying medical illness are the major risk factors for COVID-19-related fatal respiratory dysfunction. The reason for the pathogenicity of COVID-19 in the older age group remains unclear. Factors, such as coagulopathy, cytokine storm, metabolic disrup-tion, and impaired T cell function, may worsen the symptoms of the disease. Recent literature has indicat-ed that viral infections are particularly associated with a high degree of oxidative stress and an imbalance of antioxidant response. Although pharmacological management has taken its place in reducing the severity of COVID-19, the antioxidants can serve as an adjunct therapy to protect an individual from oxidative damage triggered by SARS-CoV-2 infection. In general, antioxidant enzymes counteract free radicals and prevent their formation. The exact functional role of antioxidant supplements in reducing disease symptoms of SARS-CoV-2 infection remains mostly unknown. In this review, the functional role of natural antioxidants in SARS-CoV-2 infection management is discussed in brief.Copyright © 2022 Bentham Science Publishers.

Covid-19 Fatigue: Diagnosis and Treatment for the Osteopathic Physician

The novel coronavirus disease 2019 (COVID-19) has given rise to a global pandemic, as well as a multitude of long-term sequelae that continue to perplex physicians around the world, including in the United States. Among the most common and impactful long-haul symptoms experienced by survivors is COVID-19 fatigue. This review will use long COVID-19, post-acute COVID-19 syndrome (PCS), and PostAcute Sequelae of COVID-19 (PASC) as synonymous terms to refer to the chronic symptomatology;chronic fatigue associated with PASC will be referred to as COVID-19 fatigue. While the knowledge and research on the exact pathophysiological mechanisms involved in the disease is still limited, parallels have been drawn between fatigue as a component of long COVID-19 and myalgic encephalomyelitis/ chronic fatigue syndrome (ME/CFS). Current studies suggest applying principles of pathophysiology, diagnosis, and treatment similar to those for ME/CFS in order to aid in managing chronic fatigue in COVID-19 survivors, particularly in the primary care setting. The osteopathic family physician can use the proposed pharmacologic agents, along with osteopathic manipulative treatment (OMT), as therapeutic modalities that can be tailored to each patient's unique case. Nevertheless, research on proven successful treatments is still scarce. For that reason, it is essential that COVID-19 fatigue is recognized early, especially since its longitudinal impacts may be debilitating for many. This review of the available literature on COVID-19 fatigue aims to help provide quality care and lessen the disease burden experienced by patients.Copyright © 2023 by the American College of Osteopathic Family Physicians. All rights reserved.

A discussion of heat generation during a fever

Fever can be caused by pathogen infection. We analyze the thermogenesis mechanism and reveal that heat is naturally generated during the immune system's fight against pathogen infection. Particularly, the heat production by reactive oxygen species that originates in the respiratory burst significantly contributes to the fever development. This analysis can help address mechanisms of SARS-CoV-2 pathogenesis or provide a foundation for future mechanistic inquiries.Copyright © 2022, Research Trends (P) LTD.. All rights reserved.

PLASMA FROM SARS-COV-2 PATIENTS INDUCES OXIDATIVE STRESS AND ENDOTHELIAL DYSFUNCTION VIA ANGIOTENSIN II TYPE 1 RECEPTOR (AT1R)/P38 MAPK PATHWAY

Background: Acute respiratory distress syndrome (ARDS) is a distinctive feature of severe COVID-19 infections that occurs mainly in patients with coexisting health problems, such as hypertension, atherosclerosis, and diabetes. Endothelial dysfunction is a major contributing factor during ARDS development in COVID- 19 patients with pre-existing comorbidities. Objective: Studying the mechanism by which endothelial activation and dysfunction could provide a therapeutic target for COVID-19 treatment. Design and method: The current study measured endothelial dysfunction and oxidative stress by incubating human umbilical vein endothelial cells (HUVECs) with plasma from patients with mild, moderate, severe and extremely severe COVID- 19. Using flow cytometry, wound-healing assays and phosphokinase arrays, Results: We detected increases in cell apoptosis;reactive oxygen species (ROS) formation;hypoxia-inducible factor-1 alpha (HIF-1 alpha), vascular cell adhesion molecule-1 (VCAM-1), and vascular endothelial growth factor receptor-1 (VEGFR-1) expression;viral entry;and inflammatory-related protein activity. We also found an impairment in the wound-healing process. Moreover, we found that AT1R blockade and P38 MAPK inhibition reversed all of these effects, especially in the severe group. Conclusions: These findings indicate that AT1R/P38 MAPK-mediated oxidative stress and endothelial dysfunction occur during COVID-19 infection.

Magnetic mitohormesis: A non-invasive therapy for inflammatory disorders?

An organism's survival depends on its ability to adapt to stress. Mitochondria are the cellular integrators of environmental stressors that ultimately translate their responses at the organismal level, and are thus central to the process whereby organisms adapt to their respective environments. Mitochondria produce molecular energy via oxidative phosphorylation that then allows cells to biosynthetically respond and adapt to changes in their environment. Reactive oxygen species (ROS) are by-products of oxidative phosphorylation that can be either beneficial or damaging, depending on the context;ROS are hence both the conveyors of environmental stress as well as cellular "adaptogens”. Mitohormesis refers to the process whereby low levels of oxidative stress spur survival adaptations, whereas excessive levels stymie survival. Low energy and frequency pulsing electromagnetic fields have been recently shown capable of stimulating mitochondrial respiration and ROS production and instilling mitohormetic survival adaptations, similarly to, yet independently of, exercise, opening avenues for the future development of Magnetic Mitohormetic interventions for the improvement of human health. This viewpoint explores the possibilities and nuances of magnetic-based therapies as a form of clinical intervention to non-invasively activate magnetic mitohormesis for the management of chronic diseases. © 2023 Centro Regional de Invest. Cientif. y Tecn.. All rights reserved.

Promoting improved healing: Lessons learned from the fetus

Background: It has long been known that the fetal response to skin injury is regenerative, with a lack of abnormal collagen deposition or scar, and restoration of normal dermal architecture. This response is associated with minimal inflammation.We have shown that the decreased inflammation is due to decreased production of pro-inflammatory cytokine production compared to the adult response. In addition, we have shown fetal tendon and the fetal heart can heal by regeneration, with restoration of structure and function, and is also associated with decreased proinflammatory cytokine production and decreased inflammation. We hypothesized that strategies targeting inflammation and associated oxidative stress could be used in adult diseases. We have identified diabetic wounds, acute lung injury, and colitis where inflammation and oxidative stress plays a central role in the pathogenesis the disease. Material(s) and Method(s): We have developed a novel strategy using nanotechnology to target inflammation and oxidative stress. We have conjugated novel cerium oxide nanoparticles, which act as potent scavengers of reactive oxygen species, to the anti-inflammatory microRNA miR146a, which suppresses the NFkB pathway and the production of the pro-inflammatory cytokines IL-6 and IL-8. Result(s): In diabetic wounds, impaired healing is associated with chronic inflammation and oxidative stress. We have demonstrated, in both small and large diabetic animals models, that CNP-miR146a can decrease inflammation and oxidative stress and correct the diabetic wound healing impairment and promote regeneration, similar to rates of healing in non-diabetic animals. We have also examined other disease states where inflammation and oxidative stress is pathogenic. Following acute lung injury, inflammation and oxidative stress leads to the development of adult respiratory distress syndrome or ARDS, the number one cause of mortality with COVID-19, and is associated with a 30-50% mortality. Inflammation and oxidative stress play a central role in the pathogenesis of ARDS. We have shown in models of acute lung injury, including bleomycin, LPS, MRSA, ventilator induced lung injury (VILI) and mustard gas, that CNP-miR146a decreases inflammation and oxidative stress, promotes regeneration and restoration of function, and decreased mortality. Finally, pathogenic inflammation plays a central role in the development of colitis or inflammatory bowel disease. We have shown that CNP-miR146a enemas can prevent progression of disease, restore weight gain, and lacks the adverse effects of systemic immunosuppression. Conclusion(s): We have used our understanding of the mechanisms of fetal regeneration following injury, which progresses with minimal inflammation and oxidative stress, to develop strategies targeting these processes to promote regeneration in adult disease.

The central role of neutrophil extracellular traps in SARS-CoV-2-induced thrombogenesis and vasculitis

Objective: Severe acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) seen in SARs-CoV-2 infection has been attributed to the disruption of the immune response in COVID-19 patients. Neutrophilia and marked lymphocyte reductions are associated with disease severity and seem predictive of disease outcome in moderate and severe COVID-19 patients. Herein, we aim to decipher possible mechanisms involved in extensive tissue injury observed in COVID-19 patients, accompanied by vasculopathy, coagulopathy, and a high incidence of thrombotic complications in severe patients. Method(s): We searched PubMED for keywords including COVID-19 pathogenesis, thrombosis, and vasculities. Result(s): Neutrophils can undergo a specialized form of apoptosis to yield thread-like extracellular structures termed neutrophil extracellular traps (NETs), termed NETosis, which form web-like scaffolds of DNA, histones, and toxic protein granules and enzymes, whose primary function is to trap and eliminate microbes. However, uncontrolled NET production can lead to ALI and ARDS, coagulopathy, multiple organ failure, and autoimmune disease. Dysregulation of NETs promotes production of anti-neutrophil cytoplasmic antibodies (ANCA) which affects small vessels through ANCA-associated vasculitis (AAV). Furthermore, NETs can also induce thrombosis via formation of scaffolds that trap platelets, RBCs, fibronectin, and other proteins, which can also induce coagulation. Conclusion(s): We suggest that NET production is central during SARS-CoV-2 infection and COVID-19 pathogenesis, associated with alveolar damage accumulation of edema, endothelial injury and coagulopathy, elevated platelet activation and thrombogenesis forming a NET production feed-forward loop, causing diffuse small vessel vasculitis in the lungs and other organs. Copyright © 2020 FSG Communications Ltd. All rights reserved.

Bortezomib- and carfilzomib-resistant myeloma cells show increased activity of all three arms of the unfolded protein response

Proteasome inhibitors are among the most potent classes of drugs in multiple myeloma treatment. One of the main challenges in myeloma therapy is acquired resistance to drugs. Several theories have been proposed to describe the mechanisms responsible for resistance to the most commonly used proteasome inhibitors bortezomib and carfilzomib. This study aimed to describe functional differences between sensitive myeloma cells (MM1S WT) and their daughter cell lines resistant to either bortezomib (MM1S/R BTZ) or carfilzomib (MM1S/R CFZ), as well as between both resistant cell lines. Bortezomib- and carfilzomib-resistant cell lines were successfully generated by continuous exposure to the drugs. When exposed to different drugs than during the resistance generation period, MM1S/R BTZ cells showed cross-resistance to carfilzomib, whereas MM1S/R CFZ cells were similarly sensitive to bortezomib as MM1S WT cells. Following proteomic profiling, unsupervised principal component analysis revealed that the MM1S/R BTZ and MM1S/R CFZ cell lines differed significantly from the MM1S WT cell line and from each other. Canonical pathway analysis showed similar pathways enriched in both comparisons - MM1S WT vs. MM1S/R CFZ and MM1S WT vs. MM1S/R BTZ. However, important differences were present in the statistical significance of particular pathways. Key alterations included the ubiquitin-proteasome system, metabolic pathways responsible for redox homeostasis and the unfolded protein response. In functional studies, both drugs continued to reduce chymotrypsin-like proteasome activity in resistant cells. However, the baseline activity of all three catalytic domains of the proteasome was higher in the resistant cells. Differences in generation of reactive oxygen species were identified in MM1S/R BTZ (decreased) and MM1S/CFZ cells (increased) in comparison to MM1S WT cells. Both baseline and drug-induced activity of the unfolded protein response were higher in resistant cells than in MM1S WT cells and included all three arms of this pathway: IRE1α/XBP1s, ATF6 and EIF2α/ATF4 (downstream effectors of PERK). In conclusion, contrary to some previous reports, resistant MM1S cells show upregulation of unfolded protein response activity, reflecting the heterogeneity of multiple myeloma and prompting further studies on the role of this pathway in resistance to proteasome inhibitors.

EFFECTIVENESS OF ZINC AND ROS ON TESTOSTERONE HORMONE LEVELS FOR RECOVERING COVID-19 PATIENTS

COVID-19 (coronavirus disease 2019), cause severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) across all age groups, it’s a positive-sense single-stranded RNA virus, and a member of the Betacoronavirus genus taxonomically (Jiang et al, 2020). Given the importance roles of zinc in combating oxidative damage and viral infections, Zinc also has confirmed roles in both male and female reproduction. The possible depletion of zinc with the oxidative events of COVID-19 is especially relevant to the fertility of affected couples (Sethuram et al, 2021). The aim of study is to determine the relation between zinc value and oxidative stress level represented by ROS (Reactive Oxygen Species) and testosterone level among the recovered COVID-19 patients in reproductive age. 120 men chosen from Center of Medical City, Health Center of 9 Nisan, Poisoning Consultation Center and Kamal AL-Samarrai Hospital, 70 recovered males from COVID-19 within a period of 6 months after the last negative PCR nasopharyngeal swab and 50 as control group (uninfected COVID-19) from the Medical staff and the relatives, during the period from December/ 2020 to February / 2021. Testosterone hormone level were measured for each male, level of COVID-19 anti-nucleocapsid IgG was estimated and designed as selection criteria for recovery from COVID-19. Pearson’s correlation coefficient and A stepwise method in linear regression statistic test was applied to detect the association of testosterone hormone level with zinc and ROS. The mean and standard deviation level of studied parameters are differ between cases of current studying;recovering COVID-19 males and control group then compared with normal value of each test. The levels of COVID-19 anti-nucleocapsid IgG increase among recovering males compared with control group, statistically highly-significant (P-value = 0.00), as well oxidative stress among cases recovered from Covid-19 compared with level of control are statistically highly-significant (P-value= 0.00), while levels of zinc are decreased among cases studied compared with control group, this differences was highly-significant (P-value = 0.00). In conclusion, the most factors affecting Testosterone hormone level identified in the study are Zinc, ROS

ELEVATED ROS LEVELS AND DNA FRAGMENTATION IN SPERM FROM CONVALESCENT MEN IN SARS-COV-2 INFECTION

INTRODUCTION AND OBJECTIVE: Current evidence has proven the systemic nature of COVID19, including its involvement in the male reproductive tract. We aimed to investigate seminal parameters of moderate-to-severe COVID-19 men during the convalescence phase. METHODS: This cross-sectional study included 18 to 50-yearold men with confirmed moderate-to-severe COVID-19. Patients were enrolled 15 to 45 days after the diagnosis. After a urologist's initial clinical evaluation, semen samples were obtained by masturbation and processed within one hour. Semen analysis was performed using the World Health Organization (WHO) manual (6th edition). Sperm function tests were conducted in an andrology laboratory, including Reactive oxygen species (ROS), DNA fragmentation, lipid peroxidation, and Creatine Kinase (CK) analysis. An essential endocrine evaluation was performed. Patients with a history of disorders that could impair testicular function were excluded. A group of pre-vasectomy baseline samples was used as a control group. Statistical analysis was performed using R version 4.0.5. One-tailed and paired T-tests were used for comparisons between groups. RESULTS: The sample size was 26 men (mean 34.3±6.5 years;range: 21-50 years). Sperm concentration (mean 38.74±32, P <0.01) and total motile count (mean 55.3±66.8, P <0.01) were significantly reduced in the COVID-19 group. The DNA fragmentation (mean 41.1±29.2) and ROS (mean 4.84±8.7) were significantly higher in post-infection patients. Other parameters such as WHO/ Kruger morphology and progressive motility were also reduced in the disease group, albeit not statistically significant. Total testosterone (mean 409.2±201.2) was lower in the convalescent men. All semen samples were negative for SARS-CoV-2 using the PCR analysis. CONCLUSIONS: Our findings indicate that male reproductive injury can be a relevant component of SARS-CoV-2 systemic infection. High DNA fragmentation and ROS, hallmarks of tissue injury, might signal a direct testicular involvement. The morphological and functional damage could represent significant impairment of the male reproductive health if persistent after convalescence.

CRYOPRESERVED SEMINAL SAMPLES FROM PATIENTS WITH ACUTE COVID-19 HAVE THE WORST POST-THAW QUALITY WHEN COMPARED TO OTHER ANDROLOGICAL DISEASES

OBJECTIVE: To evaluate the effect of COVID-19 in sperm cryopreservation processes, including functional parameters evaluated pre-cryopreservation and post-thaw, and to compare post-thaw results from COVID-19 patients to samples from others systemic and andrological Disease MATERIALS AND METHODS: In this cross-sectional study, 37 semen samples of male patients aged 18 to 45 years at Division of Urology, Department of Surgery, Hospital das Clinicas of the University of Sao Paulo or at Androscience- Science and Innovation Center in Andrology, High-Complex Clinical and Research Andrology Laboratory, were initially recruited from April 2020 to April 2021. Patients were categorized as acute COVID-19 (n=15), confirmed by RT-PCR (COVID-19 group), and healthy individuals with normozoospermic semen samples (n=22;Control group). Were evaluated seminal parameters, cryosurvival rates (%), mitochondrial activity (%;3,30 -diaminobenzidine stain), reactive oxygen species levels (ROS;chemiluminescent technique) and DNA fragmentation (%;SCSA method) in precryopreservation and post-thaw samples. Samples were cryopreserved by the slow freezing technique. A complementary retrospective study was performed comparing post-thawed samples from COVID-19 group with data from patients with others male diseases: Male infertility (n=35);Severe infertility (n=62), caused severe oligozoospermia, grade 3 varicocele, gonadal dysgenesis, testicular nodule, testicular hypotrophy;testicular cancer (n=55);and other malignant diseases (leukemia, lymphoma, sarcoma, multiple myeloma;n=30). Was used T-test to statistical analysis (p<0.05). RESULTS: Macroscopy analysis of COVID-group revealed abnormal viscosity in 53.33%, semen volume = 4.50 ± 1.72 ml and pH = 8.13 ± 0.23. COVID-19 fresh samples demonstrated mean of progressive motility = 29.07±16.83%, sperm morphology = 2.07±1.58%, and DNA fragmentation index = 42.91±33.38%. Cryopreservation decreased progressive motility (to 5.39±7.92%;p=0.02), sperm vitality (70.46±8.50 vs. 72.20±23.27;p=0.042) and ROS (0.516±0.978 vs. 4.393±9.956 x 104 cpm;p=0.018). When we compared with cryopreserved normozoospermic samples, there was observed a significant difference in HDS (p=0.002). Cryosurvival rate from COVID-19 samples was 19.93;19.71%, and had significant difference when compared with severe infertility (40.16;31.05%;p=0.003), and other malignant diseases (53.14;28.55%, <0.001). CONCLUSIONS: Seminal samples from patients with COVID-19 showed reduced fertile potential, especially when compared to the reference values. In the comparisons performed with samples from patients with different andrological diagnoses, common in the specialized andrology laboratory routine, we can suggest that samples from patients with the acute form of COVID-19 had the worst quality, with low cryosurvival rates. This information contribute to the conduct of these patients during assisted reproduction routines and preservation of male fertility. IMPACT STATEMENT: It will contribute to conducts in the cryopreservation of sperm in patients with acute COVID-19.

SARS-CoV-2 SPIKE BINDS FIBRINOGEN-INDUCING ABNORMAL INFLAMMATORY BLOOD CLOTS

Background: Life threatening thrombotic events involving both the arterial and venous systems are prominently present in SARS-CoV-2 infected individuals presenting with severe COVID-19. Abnormal clotting also occurs in asymptomatically or mildly infected individuals and in people experiencing post-acute sequelae of SARS-CoV-2 infection (PASC). Clinical management of this clotting disorder has proven difficult in part because these fibrin clots are highly resistant to plasmin-mediated fibrinolysis. Methods: An array of different binding, biochemical, microscopic, and in vivo assays were performed in these studies. All experiments were performed at least three times in triplicate and reported differences were shown to be statistically significant. Results: We find that SARS-CoV-2 Spike directly binds to the terminal clotting factors, fibrinogen and fibrin (Kd of 5.3 μ M and 0.4 μ M respectively). Mixing Spike and plasma accelerates fibrin polymerization. Scanning electron microscopy reveals an abnormal clot structure with finer, denser, and roughened fibrin fibers. Scanning peptide competition assays indicate Spike binds fibrin at three sites: 1) the plasmin cleavage site needed for fibrinolysis;2) a site involved in innate immune signaling via fibrin binding to Complement Receptor 3 (CR3);and 3) a site with no known function. Examination of mice injected 24h earlier with Spike pseudotyped HIV-ΔEnv virions reveals extensive intra-and extravascular fibrin deposition in the lung accompanied by endothelial activation, loss of tight junctions, increased influx of macrophages, and the generation of high levels of reactive oxygen species. This thromboinflammatory response is not observed when Bald virions are injected or when Spike pseudotyped virions are injected into mice lacking fibrinogen. Intriguingly, these Spike-induced proinflammatory effects are blocked by an anti-fibrin monoclonal antibody, 5B8, which interferes with fibrin binding to CR3. Conclusion: Our findings reveal that the SARS-CoV-2 Spike protein binding to fibrinogen/fibrin results in the formation of structurally abnormal, fibrinolysis-resistant blood clots whose inflammatory effects are effectively neutralized by a specific fibrin-targeting monoclonal antibody. While COVID-19 clotting was thought to occur as a result of systemic inflammation, our findings suggest clotting during SARS-CoV-2 infection in fact is a driver of inflammation. Targeting fibrin could lead to novel therapeutic approaches for patients with acute COVID-19 and PASC.

ANGIOTENSIN II CAUSES T LYMPHOPENIA VIA REACTIVE OXYGEN SPECIES in SEVERE COVID-19

Background: The aim of this study was to identify the cause of lymphopenia, strongly predictive of survival in COVID-19. Methods: We recruited PCR-positive SARS-CoV-2-infected patients upon admission to Intensive Care Units (ICU, n = 29) and to the Infectious Diseases Department (non-ICU, n = 29) at Nîmes University Hospital, as well as age-and sex-matched healthy controls (HC). Their Angiotensin II plasma levels were measured by ELISA and their monocytic reactive oxygen species (ROS) production and T-cell apoptosis were measured by flow cytometry using dichloro-dihydro-fluorescein diacetate and fluorescent annexin V, respectively. DNA damage and double strand breaks were quantified in immunofluorescence using antibodies specific for-γ-H2AX and 53BP1, respectively. Results: The monocytes of certain COVID-19 patients spontaneously released ROS able to induce DNA damage and apoptosis in neighboring cells. High ROS production was predictive of death. Indeed, in most patients we observed the presence of DNA damage in up to 50% of their peripheral mononuclear blood cells, with double-strand DNA breaks, and T-cell apoptosis. The intensity of this DNA damage was linked to lymphopenia. SARS-CoV-2 is known to induce the internalization of its receptor, Angiotensin Converting Enzyme 2, a protease able to catabolize Angiotensin II. Accordingly, we observed high plasma levels of Angiotensin II in ROS-producing patients. In search of the stimulus responsible for their ability to release ROS, we unveiled that Angiotensin II triggers ROS production by monocytes via Angiotensin receptor I (AT1). ROS released by Angiotensin II-activated monocytes induced DNA damage and apoptosis in neighboring cells. Conclusion: Mononuclear cell apoptosis provoked via DNA damage due to the release of monocytic ROS could play a major role in COVID-19 pathogenesis, inasmuch as ROS are also known to trigger inflammatory cytokine production. Unveiling this new pathogenic pathway opens up new therapeutic possibilities for COVID-19 based on the early association of AT1 antagonists and antioxidants.

COVID-19 Treatment Options and Their Mechanism of Action up to Now: An Overview of Clinical Trials

Novel coronavirus causes the outbreak of COVID-19. There is still no verified treatment regimen against this novel virus;however, different drugs and compounds have been tested against it. Ample proposals have led to a good understanding of pathogenesis and drug efficacy against the novel virus disease. Excess systemic inflammation, which is described as cytokine storm, in the severe cases of COVID-19 can pass through the blood-brain barrier, enter the brain tissue, and activate the microglial cells and oligodenritcytes. Activation of the microglia cells and oligodenritcytes can increase generation of reactive oxygen species in the brain. Excess generation of reactive oxygen species can in turn increase neuro-inflammation in some cases of patients with COVID-19. Treatment of COVID-19 is far from clear. Today, some antiviral drugs such as remdisivir, favipiravir, ribavirin, kaletra, and arbidol are being tested against the disease. Besides these drugs, corticosteroids, anti-malaria drugs (such as chloroquine family), anticoagulants (such as heparin or enoxaparin) are repurposed. In this paper, first we explained the pathogenesis of COVID-19 particles, particularly in the brain. Second, we reviewed recent treatment options up to now, including interferon therapy, convalescent plasma exchange, plasmapheresis, immunoglobin therapy, and use of specified monoclonal anti-bodies in COVID-19 patients.

Exposures to Heat-Inactivated SARS-CoV-2 Causes Reactive Oxygen Species Generation And Inflammatory Response in RAW 264.7 Cells

Introduction and Objectives Novel SARS-CoV-2 virus has been implicated in prompting a bold immune response that leads to severe Coronavirus disease 2019 (COVID-19). Recent studies have shown that SARSCoV-2-infected monocytes and macrophages are stimulated to produce an overabundance of pro-inflammatory cytokines and chemokines to generate a cytokine storm. Cytokines in excess can contribute to local tissue inflammation and the pathogenesis of COVID-19. However, the mechanism by which SARS-CoV-2 signal macrophage-derived inflammatory response remains unclear. In the present study, we used RAW 264.7 cells, a wellcharacterized macrophage model, to study the in vitro effects of SARS-CoV-2 on reactive oxygen species (ROS) production and its potential role in the signal transduction of cytokine production. Methods The effect of SARS-CoV-2 on ROS and cytokine generation in macrophages was assessed by treating RAW 264.7 cells with SARS-CoV-2 heat inactivated virus (0-20 million viral particles) or recombinant proteins for 24 hours. 2',7'-Dichlorodihydrofluorescein (2',7'-DCF) fluorescence analysis was utilized to quantify ROS generation within the RAW 264.7 macrophage cell line. Cell culture medium was sampled to quantify the levels of tumor necrosis factor (TNF) using enzyme-linked immunosorbent assay (ELISA). To assess the effects of SARS-CoV-2 on mitochondrial function, cells were treated with SARS-CoV-2 heat inactivated virus (0-20 million viral particles) for 24 hrs. Mitochondria-derived superoxide was measured using the MitoSOX™ red mitochondrial superoxide indicator. Results Treatment of RAW 264.7 cells with inactivated SARS-CoV-2 viral particles or recombinant proteins stimulated ROS production. Mitochondria-derived superoxide and hydrogen peroxide production were increased in response to inactivated SARS-CoV-2 viral particles and recombinant protein exposure. The increased ROS generation is linked to macrophage activation induced by SARS-CoV-2 exposures. Along with the ROS generation, increased TNF production was observed. Conclusions The results of this study suggest that both SARS-CoV-2 viral proteins and heat-inactivated viral particle exposures cause significant generation of ROS and cytokines by RAW 264.7 cells. ROS generation and the subsequent cytokine release apparently play a significant role in the pathogenesis associated with the SARS-CoV-2 viral infection. The imbalanced cellular defense system against oxidative stress commonly associated with aging could explain the increased occurrence of more severe SARS-CoV-2 illness in seniors and in patients with underlying health conditions. Based on the results from this study, we propose that antioxidants such as N-acetyl-L-cysteine, resveratrol, or Vitamin E in combination with antiinflammatory drug could be used to control excess ROS and cytokines in patients with severe COVID-19.

The time-dependency of the cyclobutane pyrimidine dimer-evoked cellular damages using a CPD-specific photolyase-encoding mRNA-based model system

UVB damages DNA predominantly by the formation of cyclobutane pyrimidine dimers (CPDs) that are repaired by nucleotide excision repair system in humans. Organisms more primitive than placental mammals remove CPDs by photolyase in a process of photoreactivation that uses the energy of visible light. Our previously established model system based on transient transfection of human keratinocytes with in vitro transcribed CPD-photolyase mRNA containing 1-methylpseudouridine modifications (CPD-PL mRNA). The RNA composition is similar to that used in the BioNTech COVID-19 vaccine. Immediately, 6, 8, 12 and 24 hours after UVB irradiation, CPD-PL mRNA- transfected HaCaT and NHEK keratinocytes were either exposed to photoreactivating light or kept in the dark. Keratinocytes express functional photolyase upon transfection of CPD-PL mRNA. CPDs were effectively removed by photoreactivation immediately as well as 6 hour after transfection relieving the negative effects of UVB on cell viability and prevented the loss of cell proliferation and G2/M cell cycle block. Using our model system, it has been proved that CPDs are responsible for production of mitochondrial reactive oxygen species followed by the activation of several energy sensor enzymes, and compensatory metabolic changes in keratinocytes exposed to UVB. CPDs could be removed not only from nuclear genome but from mitochondrial genome as well and restored mitochondrial DNA copy number suggesting that damage to mitochondria can also be repaired by photolyase activation. UVB-induced mutagenesis was completely abrogated by photoreactivation emphasizing the key role of CPDs in mediating DNA damage and carcinogenesis. These results suggest that activation of a non-human photolyase encoded by nucleoside-modified mRNA is able to prevent UVB-induced cellular damage even hours after UVB exposure.