Therapeutic Strategies For COVID-19 Research Articles

Taming the SARS-CoV-2-mediated proinflammatory response with BromAc®.

In the present study, the impact of BromAc®, a specific combination of bromelain and acetylcysteine, on the SARS-CoV-2-specific inflammatory response was evaluated. An in vitro stimulation system was standardized using blood samples from 9 healthy donors, luminex assays and flow cytometry were performed. BromAc® demonstrated robust anti-inflammatory activity in human peripheral blood cells upon SARS-CoV-2 viral stimuli, reducing the cytokine storm, composed of chemokines, growth factors, and proinflammatory and regulatory cytokines produced after short-term in vitro culture with the inactivated virus (iSARS-CoV-2). A combined reduction in vascular endothelial growth factor (VEGF) induced by SARS-CoV-2, in addition to steady-state levels of platelet recruitment-associated growth factor-PDGFbb, was observed, indicating that BromAc® may be important to reduce thromboembolism in COVID-19. The immunophenotypic analysis of the impact of BromAc® on leukocytes upon viral stimuli showed that BromAc® was able to downmodulate the populations of CD16+ neutrophils and CD14+ monocytes observed after stimulation with iSARS-CoV-2. Conversely, BromAc® treatment increased steady-state HLA-DR expression in CD14+ monocytes and preserved this activation marker in this subset upon iSARS-CoV-2 stimuli, indicating improved monocyte activation upon BromAc® treatment. Additionally, BromAc® downmodulated the iSARS-CoV-2-induced production of TNF-a by the CD19+ B-cells. System biology approaches, utilizing comprehensive correlation matrices and networks, showed distinct patterns of connectivity in groups treated with BromAc®, suggesting loss of connections promoted by the compound and by iSARS-CoV-2 stimuli. Negative correlations amongst proinflammatory axis and other soluble and cellular factors were observed in the iSARS-CoV-2 group treated with BromAc® as compared to the untreated group, demonstrating that BromAc® disengages proinflammatory responses and their interactions with other soluble factors and the axis orchestrated by SARS-CoV-2. These results give new insights into the mechanisms for the robust anti-inflammatory effect of BromAc® in the steady state and SARS-CoV-2-specific immune leukocyte responses, indicating its potential as a therapeutic strategy for COVID-19.

No time for complacency on COVID-19 in Europe

While the world is transitioning out of the emergency phase of the COVID-19 pandemic,1WHOStatement on the fifteenth meeting of the IHR (2005) Emergency Committee on the COVID-19 pandemic.https://www.who.int/news/item/05-05-2023-statement-on-the-fifteenth-meeting-of-the-international-health-regulations-(2005)-emergency-committee-regarding-the-coronavirus-disease-(covid-19)-pandemicDate: May 5, 2023Date accessed: May 14, 2023Google Scholar new surges of COVID-19 continue to occur across Europe because of persistent viral circulation and the regular emergence of new subvariants of omicron.2Lenharo M WHO declares end to COVID-19's emergency phase.Nature. 2023; (published online May 5.)https://doi.org/10.1038/d41586-023-01559-zCrossref Google Scholar New infections occur even during the summer months, a notable difference with influenza virus or other seasonal respiratory infections.3Gavenčiak T Monrad JT Leech G et al.Seasonal variation in SARS-CoV-2 transmission in temperate climates: a Bayesian modelling study in 143 European regions.PLoS Comput Biol. 2022; 18e1010435Crossref PubMed Scopus (1) Google Scholar The breadth of the most recent COVID-19 waves remains difficult to assess, because of a steep reduction in diagnostic testing across the continent. None of the waves of COVID-19 since the spring of 2022 overwhelmed health-care systems in Europe, or warranted new restrictions from December, 2022. Yet, excess mortality, although not only attributable to COVID-19, has been and remains unacceptably high.4EuroMOMOEuroMOMO Bulletin, week 17, 2023.https://www.euromomo.eu/Date: 2023Date accessed: May 7, 2023Google Scholar COVID-19 claimed the lives of 467 921 people in Europe during 2022.5Our World in DataCoronavirus (COVID-19) deaths.https://ourworldindata.org/covid-deathsDate: 2023Date accessed: April 25, 2023Google Scholar Hospital admissions of new patients with COVID-19 continue; infections persist in immunocompromised people; and vulnerable individuals with comorbidities remain at high risk of severe COVID-19. Persisting symptoms are also associated with 3–20% of affected people suffering from Long Covid.6Office for National StatisticsPrevalence of ongoing symptoms following coronavirus (COVID-19) infection in the UK: 30 March 2023.https://www.ons.gov.uk/peoplepopulationandcommunity/healthandsocialcare/conditionsanddiseases/bulletins/prevalenceofongoingsymptomsfollowingcoronaviruscovid19infectionintheuk/30march2023Date: 2023Date accessed: April 25, 2023Google Scholar, 7US Centres for Disease Prevention and ControlNearly one in five American adults who have had COVID-19 still have “Long COVID”.https://www.cdc.gov/nchs/pressroom/nchs_press_releases/2022/20220622.htmDate: 2023Date accessed: April 25, 2023Google Scholar Persisting absenteeism from work linked to COVID-19 and to other circulating respiratory viruses since the lifting of public health measures has had negative effects on European economies.8Lovett S Colds and flu causing more work absence than Covid. The Daily Telegraph, Dec 17, 2022https://www.telegraph.co.uk/global-health/science-and-disease/britain-now-losing-working-days-flu-related-infections-covid/Date accessed: May 15, 2023Google Scholar These impacts of COVID-19 are likely to continue in the coming years if more efforts are not made to decrease the circulation of SARS-CoV-2 and mitigate its impact on public health. Options are readily available to reduce the burden of SARS-CoV-2 and other endemic respiratory pathogens. We thus question the current high level of political and societal complacency towards COVID-19 in Europe. Much more strategic attention and investments are needed now to more effectively manage COVID-19 and develop greater resilience to future respiratory pathogens. COVID-19-related control measures are not on any public health agenda in Europe at this time. Governments should, however, carefully consider which non-pharmaceutical interventions (NPIs) to relinquish and when. Furthermore, PCR tests are no longer accessible or available for free in most European countries and, since antiviral agents need to be administered within a few days after SARS-CoV-2 infection,9Li G Hilgenfeld R Whitley R De Clercq E Therapeutic strategies for COVID-19: progress and lessons learned.Nat Rev Drug Discov. 2023; (published online April 19.)https://doi.org/10.1038/s41573-023-00672-yCrossref Scopus (0) Google Scholar vulnerable people who may need treatment are typically unable to access testing in a timely way to receive the relevant treatment. Additionally, across Europe COVID-19 antigenic tests are no longer being made easily available or used at the same scale to diagnose infection, a measure which allows for the reduction of transmission risk by individuals' behaviour. Broad access to vaccines and bivalent COVID-19 vaccine boosters in Europe, including among older people, together with acquired immunity through infection, has resulted in predominantly milder forms of COVID-19.10Arbel R Peretz A Sergienko R et al.Effectiveness of a bivalent mRNA vaccine booster dose to prevent severe COVID-19 outcomes: a retrospective cohort study.Lancet Infect Dis. 2023; (published April 13.)https://doi.org/10.1016/S1473-3099(23)00122-6Summary Full Text Full Text PDF PubMed Scopus (1) Google Scholar Over the past year in Europe, there has been a major reduction in COVID-19 hospitalisations and deaths compared with the first 18 months of the pandemic.11EurostatCountry overview report: week 17 20. European Commission, 2023https://ec.europa.eu/eurostat/statistics-explained/index.php?title=Weekly_death_statisticsDate accessed: May 7, 2023Google Scholar However, the high transmissibility of subvariants of omicron has led to more infections and cases than with the initial strains, so that the absolute number of deaths in Europe remained high.12Mohsin M Mahmud S Omicron SARS-CoV-2 variant of concern: a review on its transmissibility, immune evasion, reinfection, and severity.Medicine (Baltimore). 2022; 101e29165Crossref PubMed Scopus (24) Google Scholar The public health focus has now moved away from using NPIs that could effectively reduce the circulation of SARS-CoV-2 and other respiratory agents in the population. In Europe only minimal NPIs are typically used in higher risk settings, such as health-care facilities, where rates of nosocomial transmission of SARS-CoV-2 remain high.13Knight G Mui T Stimson J et al.The contribution of hospital-acquired infections to the COVID-19 epidemic in England in the first half of 2020.BMC Infect Dis. 2022; 22: 556Crossref PubMed Scopus (0) Google Scholar, 14Read JM Green CA Harrison EM et al.Hospital-acquired SARS-CoV-2 infection in the UK's first COVID-19 pandemic wave.Lancet. 2021; 398: 1037-1038Summary Full Text Full Text PDF PubMed Google Scholar, 15Pople D Monk EJM Evans S et al.Burden of SARS-CoV-2 infection in healthcare workers during second wave in England and impact of vaccines: prospective multicentre cohort study (SIREN) and mathematical model.BMJ. 2022; 378e070379PubMed Google Scholar, 16Wee LE Conceicao EP Aung MK et al.Nosocomial SARS-CoV-2 transmission in multi-bedded hospital cubicles over successive pandemic waves: lower mortality but wider spread with Omicron despite enhanced infection-prevention measures.Infect Dis Health. 2023; 28: 81-87Summary Full Text Full Text PDF PubMed Scopus (0) Google Scholar, 17Ramos-Rincon JM Lopez-Sampalo A Cobos-Palacios L et al.Nosocomial COVID-19: a nationwide Spanish study.Gerontology. 2023; 69: 671-683Google Scholar, 18Skagseth H Jørgensen SB Reilly J Kacelnik O A new method for near real-time, nationwide surveillance of nosocomial COVID-19 in Norway: providing data at all levels of the healthcare system, March 2020 to March 2022.Euro Surveill. 2023; 282200493Crossref PubMed Scopus (0) Google Scholar Improving ventilation and indoor air quality is a crucial intervention to reduce risk of respiratory infections and evidence suggests it is both cost-effective and brings wider benefits for health and wellbeing.19Royal Academy of EngineeringInfection resilient environments, 2022.https://nepc.raeng.org.uk/infection-resilient-environmentsDate: 2023Date accessed: April 25, 2023Google Scholar, 20Morawska L Allen J Bahnfleth W et al.A paradigm shift to combat indoor respiratory infection.Science. 2021; 372: 689-691Crossref PubMed Scopus (46) Google Scholar More efforts should be developed to protect older and immunocompromised populations to reduce their risk of exposure to SARS-CoV-2 and other respiratory viruses, identifying their infection early, assessing the role of nosocomial transmissions, and treating cases in a timely way. Clinical collaborative research that involves those most at risk is important to test optimised treatment in vulnerable patients, including drug combinations or longer duration of antiviral therapies, such as the randomised controlled trial Optimisation of Antiviral Therapy in Immunocompromised COVID-19 Patients (OPTICOV) in Switzerland and France (NCT05587894). Almost all European countries have stopped providing a reliable surveillance system to monitor the circulation of SARS-CoV-2 and other respiratory viruses and its population impact. Testing and sequencing are no longer undertaken in community settings and hospitals across most regions of the continent. One can regret that close to 4 years into the pandemic, we still lack consolidation of epidemiological data related to hospitalisations and deaths associated with COVID-19 and other viral respiratory disease and disintegrated data on causes of excess mortality across almost all European countries. Revisiting the surveillance and monitoring of respiratory infectious diseases in Europe has become imperative. Europe needs to be moving towards integrated respiratory virus surveillance, building on the lessons and innovations seen during the pandemic.21WHOFrom emergency response to long-term COVID-19 disease management: sustaining gains made during the COVID-19 pandemic.https://www.who.int/publications/i/item/WHO-WHE-SPP-2023.1Date: May 3, 2023Date accessed: May 15, 2023Google Scholar Robust surveillance for respiratory diseases involves strategic investments, such as wastewater and syndromic surveillance, and update of pandemic preparedness plans.22WHO Regional Office for EuropeEuropean Centre for Disease Prevention and ControlOperational considerations for respiratory virus surveillance in Europe.https://www.ecdc.europa.eu/sites/default/files/documents/Operational-considerations-respiratory-virus-surveillance-euro-2022.pdfDate: July 18, 2022Date accessed: May 15, 2023Google Scholar, 23WHOWHO policy brief: COVID-19 surveillance, 11 April 2023.https://www.who.int/publications/i/item/WHO-2019-nCoV-Policy_Brief-Surveillance-2023.1Date: 2023Date accessed: May 15, 2023Google Scholar, 24WHOWHO launches new initiative to improve pandemic preparedness.https://www.who.int/news/item/26-04-2023-who-launches-new-initiative-to-improve-pandemic-preparednessDate: April 26, 2023Date accessed: May 15, 2023Google Scholar The European region cannot afford to be complacent in its response to COVID-19. Health authorities, research institutions, and the population still need to mitigate the impact of respiratory pathogens on public health in Europe. Governments must improve protection of vulnerable people, urgently invest in improving ventilation and indoor air quality in health-care and other settings, and revisit surveillance and monitoring systems to ensure that we are prepared to respond to future pandemics. Longer-term strategies are also needed, such as developing pandemic prevention and preparedness plans, strengthening health systems, including public health functions, improving risk communication and community engagement, and ensuring adequate human resources planning and training to counteract staff shortages across social and health systems.25European Centre for Disease Prevention and ControlLessons from the COVID-19 pandemic.https://www.ecdc.europa.eu/sites/default/files/documents/COVID-19-lessons-learned-may-2023.pdfDate: 2023Date accessed: May 7, 2023Google Scholar Europe needs to develop resilience in our public health systems for future emerging pathogens and get better prepared for other potential future health hazards responsible for public health crisis. Failure to take these steps now will result in more deaths due to COVID-19 and other respiratory pathogens and mean that we are not well prepared to respond to future public health threats. AF is Chair of and AC, DC, OD, IE, HJL, HL-Q, CN, and MK are members of the High-Level Expert Group for COVID-19 that has advised Hans Kluge since 2021. HK is the Regional Director of the WHO Regional Office for Europe. AC report grants from ViiV Healthcare, Gilead Sciences, and MSD and is the principal investigator of the OPTICOV trial. DC report institutional grant from Janssen and honoraria for lectures from Gilead and Pfizer. HJL reports grants from GSK, Merck, and a MacArthur Award for the Vaccine Confidence Project and honoraria for lectures from UNC and NYU. HL-Q was a member of the Secretariat of the Independent Panel for Pandemic Preparedness and Response. CN reports grants from the Engineering and Physical Sciences Research Council, the UK Department of Health and Social Care, the Natural Environment Research Council, NHS Scotland, and the UK Government for various projects on transmission of COVID-19; is a member of the UK Government SAGE Committee, Co-Chair of SAGE Environment and Modelling group, is a member of multiple UK and Scottish Government and NHS working groups on COVID-19, is a member of WHO ECAP, and a member of the Royal Academy of Engineering and Academy of Medical Sciences working groups on COVID-19 mitigation. MK is an independent Board member of ExevirBio, a biotechnology company designing therapeutic monoclonal antibodies against SARS Cov2. We declare no other competing interests. We thank Catherine Smallwood, Gerald Rockenschaub, and Richard Pebody, from the WHO Regional Office for Europe, for their participation in reviewing and their helpful contributions to this Comment.

SARS-CoV-2 Inhibits NRF2-Mediated Antioxidant Responses in Airway Epithelial Cells and in the Lung of a Murine Model of Infection.

Several viruses have been shown to modulate the transcription factor nuclear factor erythroid 2-related factor 2 (NRF2), the master regulator of redox homeostasis. The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), responsible for the COVID-19 pandemic, also seems to disrupt the balance between oxidants and antioxidants, which likely contributes to lung damage. Using in vitro and in vivo models of infection, we investigated how SARS-CoV-2 modulates the transcription factor NRF2 and its dependent genes, as well as the role of NRF2 during SARS-CoV-2 infection. We found that SARS-CoV-2 infection downregulates NRF2 protein levels and NRF2-dependent gene expression in human airway epithelial cells and in lungs of BALB/c mice. Reductions in cellular levels of NRF2 seem to be independent of proteasomal degradation and the interferon/promyelocytic leukemia (IFN/PML) pathway. Furthermore, lack of the Nrf2 gene in SARS-CoV-2-infected mice exacerbates clinical disease, increases lung inflammation, and is associated with a trend toward increased lung viral titers, indicating that NRF2 has a protective role during this viral infection. In summary, our results suggest that SARS-CoV-2 infection alters the cellular redox balance by downregulating NRF2 and its dependent genes, which exacerbates lung inflammation and disease, therefore, suggesting that the activation of NRF2 could be explored as therapeutic approach during SARS-CoV-2 infection. IMPORTANCE The antioxidant defense system plays a major function in protecting the organism against oxidative damage caused by free radicals. COVID-19 patients often present with biochemical characteristics of uncontrolled pro-oxidative responses in the respiratory tract. We show herein that SARS-CoV-2 variants, including Omicron, are potent inhibitors of cellular and lung nuclear factor erythroid 2-related factor 2 (NRF2), the master transcription factor that controls the expression of antioxidant and cytoprotective enzymes. Moreover, we show that mice lacking the Nrf2 gene show increased clinical signs of disease and lung pathology when infected with a mouse-adapted strain of SARS-CoV-2. Overall, this study provides a mechanistic explanation for the observed unbalanced pro-oxidative response in SARS-CoV-2 infections and suggests that therapeutic strategies for COVID-19 may consider the use of pharmacologic agents that are known to boost the expression levels of cellular NRF2.

Microfluidic-based technologies for diagnosis, prevention, and treatment of COVID-19: recent advances and future directions.

The COVID-19 pandemic has posed significant challenges to existing healthcare systems around the world. The urgent need for the development of diagnostic and therapeutic strategies for COVID-19 has boomed the demand for new technologies that can improve current healthcare approaches, moving towards more advanced, digitalized, personalized, and patient-oriented systems. Microfluidic-based technologies involve the miniaturization of large-scale devices and laboratory-based procedures, enabling complex chemical and biological operations that are conventionally performed at the macro-scale to be carried out on the microscale or less. The advantages microfluidic systems offer such as rapid, low-cost, accurate, and on-site solutions make these tools extremely useful and effective in the fight against COVID-19. In particular, microfluidic-assisted systems are of great interest in different COVID-19-related domains, varying from direct and indirect detection of COVID-19 infections to drug and vaccine discovery and their targeted delivery. Here, we review recent advances in the use of microfluidic platforms to diagnose, treat or prevent COVID-19. We start by summarizing recent microfluidic-based diagnostic solutions applicable to COVID-19. We then highlight the key roles microfluidics play in developing COVID-19 vaccines and testing how vaccine candidates perform, with a focus on RNA-delivery technologies and nano-carriers. Next, microfluidic-based efforts devoted to assessing the efficacy of potential COVID-19 drugs, either repurposed or new, and their targeted delivery to infected sites are summarized. We conclude by providing future perspectives and research directions that are critical to effectively prevent or respond to future pandemics.

SARS-CoV-2 nucleocapsid protein triggers hyperinflammation via protein-protein interaction-mediated intracellular Cl− accumulation in respiratory epithelium

SARS-CoV-2, the culprit pathogen of COVID-19, elicits prominent immune responses and cytokine storms. Intracellular Cl− is a crucial regulator of host defense, whereas the role of Cl− signaling pathway in modulating pulmonary inflammation associated with SARS-CoV-2 infection remains unclear. By using human respiratory epithelial cell lines, primary cultured human airway epithelial cells, and murine models of viral structural protein stimulation and SARS-CoV-2 direct challenge, we demonstrated that SARS-CoV-2 nucleocapsid (N) protein could interact with Smad3, which downregulated cystic fibrosis transmembrane conductance regulator (CFTR) expression via microRNA-145. The intracellular Cl− concentration ([Cl−]i) was raised, resulting in phosphorylation of serum glucocorticoid regulated kinase 1 (SGK1) and robust inflammatory responses. Inhibition or knockout of SGK1 abrogated the N protein-elicited airway inflammation. Moreover, N protein promoted a sustained elevation of [Cl−]i by depleting intracellular cAMP via upregulation of phosphodiesterase 4 (PDE4). Rolipram, a selective PDE4 inhibitor, countered airway inflammation by reducing [Cl−]i. Our findings suggested that Cl− acted as the crucial pathological second messenger mediating the inflammatory responses after SARS-CoV-2 infection. Targeting the Cl− signaling pathway might be a novel therapeutic strategy for COVID-19.

Friend or Foe? Implication of the autophagy-lysosome pathway in SARS-CoV-2 infection and COVID-19.

There is increasing amount of evidence indicating the close interplays between the replication cycle of SARS-CoV-2 and the autophagy-lysosome pathway in the host cells. While autophagy machinery is known to either assist or inhibit the viral replication process, the reciprocal effects of the SARS-CoV-2 on the autophagy-lysosome pathway have also been increasingly appreciated. More importantly, despite the disappointing results from the clinical trials of chloroquine and hydroxychloroquine in treatment of COVID-19, there is still ongoing effort in discovering new therapeutics targeting the autophagy-lysosome pathway. In this review, we provide an update-to-date summary of the interplays between the autophagy-lysosome pathway in the host cells and the pathogen SARS-CoV-2 at the molecular level, to highlight the prognostic value of autophagy markers in COVID-19 patients and to discuss the potential of developing novel therapeutic strategies for COVID-19 by targeting the autophagy-lysosome pathway. Thus, understanding the nature of such interactions between SARS-CoV-2 and the autophagy-lysosome pathway in the host cells is expected to provide novel strategies in battling against this global pandemic.

Inactivated SARS-CoV-2 induces acute respiratory distress syndrome in human ACE2-transgenic mice

The development of animal models for COVID-19 is essential for basic research and drug/vaccine screening. Previously reported COVID-19 animal models need to be established under a high biosafety level condition for the utilization of live SARS-CoV-2, which greatly limits its application in routine research. Here, we generate a mouse model of COVID-19 under a general laboratory condition that captures multiple characteristics of SARS-CoV-2-induced acute respiratory distress syndrome (ARDS) observed in humans. Briefly, human ACE2-transgenic (hACE2) mice were intratracheally instilled with the formaldehyde-inactivated SARS-CoV-2, resulting in a rapid weight loss and detrimental changes in lung structure and function. The pulmonary pathologic changes were characterized by diffuse alveolar damage with pulmonary consolidation, hemorrhage, necrotic debris, and hyaline membrane formation. The production of fatal cytokines (IL-1β, TNF-α, and IL-6) and the infiltration of activated neutrophils, inflammatory monocyte-macrophages, and T cells in the lung were also determined, suggesting the activation of an adaptive immune response. Therapeutic strategies, such as dexamethasone or passive antibody therapy, could effectively ameliorate the disease progression in this model. Therefore, the established mouse model for SARS-CoV-2-induced ARDS in the current study may provide a robust tool for researchers in the standard open laboratory to investigate the pathological mechanisms or develop new therapeutic strategies for COVID-19 and ARDS.

Mitochondrial DNA and TLR9 activation contribute to SARS-CoV-2-induced endothelial cell damage

Background and purposeMitochondria play a central role in the host response to viral infection and immunity, being key to antiviral signaling and exacerbating inflammatory processes. Mitochondria and Toll-like receptor (TLR) have been suggested as potential targets in SARS-CoV-2 infection. However, the involvement of TLR9 in SARS-Cov-2-induced endothelial dysfunction and potential contribution to cardiovascular complications in COVID-19 have not been demonstrated. This study determined whether infection of endothelial cells by SARS-CoV-2 affects mitochondrial function and induces mitochondrial DNA (mtDNA) release. We also questioned whether TLR9 signaling mediates the inflammatory responses induced by SARS-CoV-2 in endothelial cells. Experimental approachHuman umbilical vein endothelial cells (HUVECs) were infected by SARS-CoV-2 and immunofluorescence was used to confirm the infection. Mitochondrial function was analyzed by specific probes and mtDNA levels by real-time polymerase chain reaction (RT-PCR). Inflammatory markers were measured by ELISA, protein expression by western blot, intracellular calcium (Ca2+) by FLUOR-4, and vascular reactivity with a myography. Key resultsSARS-CoV-2 infected HUVECs, which express ACE2 and TMPRSS2 proteins, and promoted mitochondrial dysfunction, i.e. it increased mitochondria-derived superoxide anion, mitochondrial membrane potential, and mtDNA release, leading to activation of TLR9 and NF-kB, and release of cytokines. SARS-CoV-2 also decreased nitric oxide synthase (eNOS) expression and inhibited Ca2+ responses in endothelial cells. TLR9 blockade reduced SARS-CoV-2-induced IL-6 release and prevented decreased eNOS expression. mtDNA increased vascular reactivity to endothelin-1 (ET-1) in arteries from wild type, but not TLR9 knockout mice. These events were recapitulated in serum samples from COVID-19 patients, that exhibited increased levels of mtDNA compared to sex- and age-matched healthy subjects and patients with comorbidities. Conclusion and applicationsSARS-CoV-2 infection impairs mitochondrial function and activates TLR9 signaling in endothelial cells. TLR9 triggers inflammatory responses that lead to endothelial cell dysfunction, potentially contributing to the severity of symptoms in COVID-19. Targeting mitochondrial metabolic pathways may help to define novel therapeutic strategies for COVID-19.

Hispidin and Lepidine E: Two Natural Compounds and Folic Acid as Potential Inhibitors of 2019-novel Coronavirus Main Protease (2019- nCoVMpro), Molecular Docking and SAR Study

2019-nCoV is a novel coronavirus was isolated and identified in 2019 in Wuhan, China. On 17th February and according to world health organization, a number of 71 429 confirmed cases worldwide, among them 2162 new cases recorded in the last 24 hours. There is no drug or vaccine for human and animal coronavirus. The inhibition of 3CL hydrolase enzyme provides a promising therapeutic principle for developing treatments against CoViD-19. The 3CLpro (Mpro) known for involving in counteracting the host innate immune response. This work presents the inhibitory effect of some natural compounds against 3CL hydrolase enzyme, and explain the main interactions in inhibitor-enzyme complex. Molecular docking study carried out using Autodock Vina. By screening several molecules, we identified three candidate agents that inhibit the main protease of coronavirus. Hispidin, lepidine E, and folic acid bound tightly in the enzyme, strong hydrogen bonds have been formed (1.69-1.80&[Aring]) with the active site residues. This study provides a possible therapeutic strategy for CoViD-19.

Medical progress: Stem cells as a new therapeutic strategy for COVID-19.

Currently, the world is facing the SARS-CoV-2 pandemic, coronavirus of acute respiratory distress syndrome 2, causes of COVID-19. Coronaviruses are RNA single-stranded viruses that have an envelope. In addition, coronaviruses are classified into four subfamilies: alpha, beta, gamma and delta coronaviruses. The first of them, cause mildly symptomatic or asymptomatic infections, while beta-coronaviruses are responsible for severe diseases. SARS-CoV-2 belongs to the group of beta-coronaviruses. Current available therapies use corticosteroids to reduce inflammation, non-specific antiviral drugs or antibiotics in the treatment of secondary bacterial infections. In addition, therapies based on the use of hydroxychloroquine, chloroquine, remdesvir, ribavirin, interferon or lopinavir-ritonavir were also initially used. Mesenchemical stem cells (MSCs) are widely used in cell therapies, which include both basic research and clinical trials. Their exceptional effectiveness and safety have been confirmed and documented in many clinical studies, which include a number of inflammatory diseases involving the immune system – one of them is systemic lupus erythematosus. Available data indicate the ability to differentiate MSCs and their immunomodulatory effects. In addition, through interactions with immune cells, which include, but are not limited to, macrophages and dendritic cells, or paracrine secretion, MSCs are able to secrete a number of types of cytokines. MSCs are also characterized by tissue regeneration and regulation of inflammation. Due to their properties, researchers turned to determine whether MSC transplantation is able to improve the outcome of patients with COVID-19 viral pneumonia. The presented review provides not only new knowledge in the field of molecular mechanisms of pro-regenerative action of stem cells, but also have the potential to open up new prospects of action to improve lung tissue regeneration in COVID-19 patients. In addition, in review mentioned about clinical trials using MSCs with a complete status, as well as the latest discoveries in molecular biology, a platform model of pluripotent stem cells in the SARS-CoV-2 study on 3D animal models and nanoconjugates based on stem cells.

Challenges for Targeting SARS-CoV-2 Proteases as a Therapeutic Strategy for COVID-19.

Two proteases produced by the SARS-CoV-2 virus, the main protease and papain-like protease, are essential for viral replication and have become the focus of drug development programs for treatment of COVID-19. We screened a highly focused library of compounds containing covalent warheads designed to target cysteine proteases to identify new lead scaffolds for both Mpro and PLpro proteases. These efforts identified a small number of hits for the Mpro protease and no viable hits for the PLpro protease. Of the Mpro hits identified as inhibitors of the purified recombinant protease, only two compounds inhibited viral infectivity in cellular infection assays. However, we observed a substantial drop in antiviral potency upon expression of TMPRSS2, a transmembrane serine protease that acts in an alternative viral entry pathway to the lysosomal cathepsins. This loss of potency is explained by the fact that our lead Mpro inhibitors are also potent inhibitors of host cell cysteine cathepsins. To determine if this is a general property of Mpro inhibitors, we evaluated several recently reported compounds and found that they are also effective inhibitors of purified human cathepsins L and B and showed similar loss in activity in cells expressing TMPRSS2. Our results highlight the challenges of targeting Mpro and PLpro proteases and demonstrate the need to carefully assess selectivity of SARS-CoV-2 protease inhibitors to prevent clinical advancement of compounds that function through inhibition of a redundant viral entry pathway.

Medical Progress: Stem Cells as a New Therapeutic Strategy for COVID-19

Abstract: Currently, the world is facing the SARS-CoV-2 pandemic, coronavirus of acute respiratory distress syndrome 2, causes of COVID-19. Coronaviruses are RNA single-stranded viruses that have an envelope. In addition, coronaviruses are classified into four subfamilies: alpha, beta, gamma and delta coronaviruses. The first of them, cause mildly symptomatic or asymptomatic infections, while beta-coronaviruses are responsible for severe diseases. SARS-CoV-2 belongs to the group of beta-coronaviruses. Current available therapies use corticosteroids to reduce inflammation, non-specific antiviral drugs or antibiotics in the treatment of secondary bacterial infections. In addition, therapies based on the use of hydroxychloroquine, chloroquine, remdesvir, ribavirin, interferon or lopinavir-ritonavir were also initially used. Mesenchemical stem cells (MSCs) are widely used in cell therapies, which include both basic research and clinical trials. Their exceptional effectiveness and safety have been confirmed and documented in many clinical studies, which include a number of inflammatory diseases involving the immune system - one of them is systemic lupus erythematosus. Available data indicate the ability to differentiate MSCs and their immunomodulatory effects. In addition, through interactions with immune cells, which include, but are not limited to, macrophages and dendritic cells, or paracrine secretion, MSCs are able to secrete a number of types of cytokines. MSCs are also characterized by tissue regeneration and regulation of inflammation. Due to their properties, researchers turned to determine whether MSC transplantation is able to improve the outcome of patients with COVID-19 viral pneumonia. The presented review provides not only new knowledge in the field of molecular mechanisms of pro-regenerative action of stem cells, but also have the potential to open up new prospects of action to improve lung tissue regeneration in COVID-19 patients. In addition, in review mentioned about clinical trials using MSCs with a complete status, as well as the latest discoveries in molecular biology, a platform model of pluripotent stem cells in the SARS-CoV-2 study on 3D animal models and nanoconjugates based on stem cells.Funding: MGP acknowledges support fromthe Iuventus Plus project of Polish Ministry of Science and Higher Education No IP 2015 022074. Declaration of Interest: None to Declare

Probiotics: An Alternative Therapeutic Strategy for Covid-19

ABSTRACT: The COVID- 19 pandemic has made the scientists today all around the globe to look for its specific prevention and treatment modalities. The disease presents itself as asymptomatic to mild to severe respiratory symptoms along with lesser common gastrointestinal symptoms of diarrhea, nausea, and vomiting. The situation worsens due to lack of precise treatment strategy. The Healthcare system is being overwhelmed, emphasizing on the need to look for alternate supportive therapy that can not only enhance the immune status of people worldwide but at the same time, ensure better prognosis. The relationship between the gut microbiota and upper and lower respiratory tract viral infections are well studied. Oral administration of probiotic microorganisms of genera Lactobacillus, Bifidobacterium and Bacillusin mice suffering from influenza infection have shown increased TNFα, IFN-γ and NK cell responses along with the production of anti-Influenza IgG. At the same time they have shown immunomodulation by producing anti-inflammatory cytokines as well as cytotoxic T-cells and T-suppressor cells. Hence, probiotic strains of generaLactobacillus, Bifidobacterium and Bacillushave shown a probability to be used as preventive and therapeutic agents for SARS- CoV-2.

Marked T cell activation, senescence, exhaustion and skewing towards TH17 in patients with COVID-19 pneumonia

The immune system of patients infected by SARS-CoV-2 is severely impaired. Detailed investigation of T cells and cytokine production in patients affected by COVID-19 pneumonia are urgently required. Here we show that, compared with healthy controls, COVID-19 patients’ T cell compartment displays several alterations involving naïve, central memory, effector memory and terminally differentiated cells, as well as regulatory T cells and PD1+CD57+ exhausted T cells. Significant alterations exist also in several lineage-specifying transcription factors and chemokine receptors. Terminally differentiated T cells from patients proliferate less than those from healthy controls, whereas their mitochondria functionality is similar in CD4+ T cells from both groups. Patients display significant increases of proinflammatory or anti-inflammatory cytokines, including T helper type-1 and type-2 cytokines, chemokines and galectins; their lymphocytes produce more tumor necrosis factor (TNF), interferon-γ, interleukin (IL)-2 and IL-17, with the last observation implying that blocking IL-17 could provide a novel therapeutic strategy for COVID-19.

COVID-19: the vasculature unleashed.

On the basis of emerging evidence from patients with COVID-19, we postulate that endothelial cells are essential contributors to the initiation and propagation of severe COVID-19. Here, we discuss current insights into the link between endothelial cells, viral infection and inflammatory changes and propose novel therapeutic strategies. Here, Carmeliet and colleagues discuss the role of endothelial cells in inflammation and viral infection and propose novel therapeutic strategies for COVID-19.

Hispidin and Lepidine E: Two Natural Compounds and Folic Acid as Potential Inhibitors of 2019-novel Coronavirus Main Protease (2019- nCoVMpro), Molecular Docking and SAR Study.

2019-nCoVis, a novel coronavirus was isolated and identified in 2019 in the city of Wuhan, China. On February 17, 2020 and according to the World Health Organization, 71, 429 confirmed cases worldwide were identified, among them 2162 new cases were recorded in the last 24 hours. One month later, the confirmed cases jumped to 179111, with 11525 new cases in the last 24 hours, with 7426 total deaths. No drug or vaccine is present at the moment for human and animal coronavirus. The inhibition of 3CL hydrolase enzyme provides a promising therapeutic principle for developing treatments against CoViD-19. The 3CLpro (Mpro) is known for involving in counteracting the host innate immune response. This work presents the inhibitory effect of some natural compounds against 3CL hydrolase enzyme, and explains the main interactions in inhibitor-enzyme complex. Molecular docking study was carried out using Autodock Vina. By screening several molecules, we identified three candidate agents that inhibit the main protease of coronavirus. Hispidin, lepidine E, and folic acid are bound tightly in the enzyme, therefore strong hydrogen bonds have been formed (1.69-1.80Å) with the active site residues. This study provides a possible therapeutic strategy for CoViD-19.

SARS-CoV-2 causing pneumonia-associated respiratory disorder (COVID-19): diagnostic and proposed therapeutic options.

SARS-CoV-2 is responsible for the outbreak of severe respiratory illness (COVID-19) in Wuhan City, China and is now spreading rapidly throughout the world. The prompt outbreak of COVID-19 and its quick spread without any controllable measure defines the severity of the situation. In this crisis, a collective pool of knowledge about the advancement of clinical diagnostic and management for COVID-19 is a prerequisite. Here, we summarize all the available updates on the multidisciplinary approaches for the advancement of diagnosis and proposed therapeutic strategies for COVID-19. Moreover, the review discusses different aspects of the COVID-19, including its epidemiology; incubation period; the general clinical features of patients; the clinical features of intensive care unit (ICU) patients; SARS-CoV-2 infection in the presence of co-morbid diseases and the clinical features of pediatric patients infected with the SARS-CoV-2. Advances in various diagnostic approaches, such as the use of real-time polymerase chain reaction (RT-PCR), chest radiography, and computed tomography (CT) imaging; and other modern diagnostic methods, for this infection have been highlighted. However, due to the unavailability of adequate evidence, presently there are no officially approved drugs or vaccines available against SARS-CoV-2. Additionally, we have discussed various therapeutic strategies for COVID-19 under different categories, like the possible treatment plans with drug (antiviral drugs and anti-cytokines) therapy for disease prevention. Lastly, potentials candidates for the vaccines against SARS-CoV-2 infection have been described. Collectively, the review provides an overview of the SARS-CoV-2 infection outbreak along with the recent advancements and strategies for diagnosis and therapy of COVID-19.

Birthweight in congenital virilizing adrenal hyperplasia.

<h3>Abstract</h3> Neutrophil extracellular traps (NETs) are web-like DNA and protein lattices which are expelled by neutrophils to trap and kill pathogens, but which cause significant damage to the host tissue. NETs have emerged as critical mediators of lung damage, inflammation and thrombosis in COVID-19 and other diseases, but there are no therapeutics to prevent or reduce NETs that are available to patients. Here, we show that neutrophils isolated from hospitalised patients with COVID-19 produce significantly more NETs in response to LPS compared to cells from healthy control subjects. A subset of patients were captured at follow-up clinics (3-4 month post-infection) and while LPS-induced NET formation is significantly lower at this time point, it remains elevated compared to healthy controls. LPS- and PMA-induced NETs were significantly inhibited by the protein kinase C (PKC) inhibitor ruboxistaurin. Ruboxistaurin-mediated inhibition of NETs in healthy neutrophils reduces NET-induced epithelial cell death. Our findings suggest ruboxistaurin could reduce proinflammatory and tissue-damaging consequences of neutrophils during disease, and since it has completed phase III trials for other indications without safety concerns, it is a promising and novel therapeutic strategy for COVID-19.