Pathophysiology and potential future therapeutic targets using preclinical models of COVID-19

SARS-CoV-2 Infection Presenting as Acute Chest Syndrome in a Child With Hemoglobin SD-Los Angeles Disease: A Case Report and Review of Literature

Hemoglobin D-Los Angeles is a variant of hemoglobin that can polymerize in the deoxygenated state. When co-inherited with Hemoglobin S (HbSD-Los Angeles disease) a severe sickling syndrome similar to HbSS can result. Corona virus infectious disease 2019 (COVID-19) is caused by the severe acute respiratory syndrome-corona virus-2. It has been associated with acute chest syndrome (ACS) in individuals with sickle cell disease (SCD), but this complication has not previously been reported in patients with HbSD-Los Angeles. Dexamethasone has been shown to improve outcomes in non-SCD patients with severe acute respiratory syndrome-corona virus-2 pneumonia or acute respiratory distress syndrome; however, its use in SCD patients with ACS is controversial due to a reported increased risk of complications including vaso-occlusive painful episodes. Herein, we reported a patient with HbSD-Los Angeles and COVID-19-associated ACS whom we treated with dexamethasone without transfusion. The patient experienced a rapid recovery without sequelae from steroid use. To further evaluate the use of steroids, we conducted a literature review focusing on the management of pediatric SCD patients with COVID-19-associated ACS. We identified a total of 39 pediatric patients with SCD and COVID-19, of whom 21 (54%) had ACS. Packed red blood cell transfusion (n=11), exchange transfusion (n=4), or a combination of exchange transfusion and packed red blood cell transfusion (n=4) were the most frequently reported treatment, with hydroxychloroquine (n=5), remdesivir (n=1), and tocilizumab (n=1) also being reported. Three patients were treated with dexamethasone. All patients recovered and no adverse outcomes from steroid use were reported. Even though transfusion is considered the standard of care for children with ACS and steroids are not routinely recommended, our experience suggested that COVID-19-associated ACS may be an important exception, especially for patients who refuse transfusion or are in resource-poor nations where blood transfusions may not be readily available. Further studies are warranted to confirm these observations.

Potential long-term effects of SARS-CoV-2 infection on the pulmonary vasculature: Multilayered cross-talks in the setting of coinfections and comorbidities

The Coronavirus Disease 2019 (COVID-19) caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) and its sublineages pose a new challenge to healthcare systems worldwide due to its ability to efficiently spread in immunized populations and its resistance to currently available therapies. COVID-19, although targeting primarily the respiratory system, is also now well established that later affects every organ in the body. Most importantly, despite the available therapy and vaccine-elicited protection, the long-term consequences of viral infection in breakthrough and asymptomatic individuals are areas of concern. In the past two years, investigators accumulated evidence on how the virus triggers our immune system and the molecular signals involved in the cross-talk between immune cells and structural cells in the pulmonary vasculature to drive pathological lung complications such as endothelial dysfunction and thrombosis. In the review, we emphasize recent updates on the pathophysiological inflammatory and immune responses associated with SARS-CoV-2 infection and their potential long-term consequences that may consequently lead to the development of pulmonary vascular diseases.

TEMPOL inhibits SARS-CoV-2 replication and development of lung disease in the Syrian hamster model

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a worldwide outbreak, known as coronavirus disease 2019 (COVID-19). Alongside vaccines, antiviral therapeutics is an important part of the healthcare response to COVID-19. We previously reported that TEMPOL, a small molecule stable nitroxide, inactivated the RNA-dependent RNA polymerase (RdRp) of SARS-CoV-2 by causing the oxidative degradation of its iron-sulfur cofactors. Here, we demonstrate that TEMPOL is effective in vivo in inhibiting viral replication in the Syrian hamster model. The inhibitory effect of TEMPOL on SARS-CoV-2 replication was observed in animals when the drug was administered 2 h before infection in a high-risk exposure model. These data support the potential application of TEMPOL as a highly efficacious antiviral against SARS-CoV-2 infection in humans.

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TEMPOL’s IC₉₀ in human lung epithelial Calu-3 cells is 2.89 μM and CC₅₀ > 10 mM

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TEMPOL has potent antiviral activity against highly pathogenic SARS- and MERS-Co-Vs

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TEMPOL inhibits SARS-CoV-2 replication and lung pathology in the Syrian hamster

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Fe-S cofactor insertion can be targeted to interfere with coronavirus replication

Safety and immunogenicity of the first Kazakh inactivated vaccine for COVID-19

This article describes the results of a preclinical safety and immunogenicity study of QazCovid-in®, the first COVID-19 vaccine developed in Kazakhstan, on BALB/c mice, rats, ferrets, Syrian hamsters and rhesus macaques (Macaca mulatta). The study's safety data suggests that this immunobiological preparation can be technically considered a Class 5 nontoxic vaccine. The series of injections that were made did not produce any adverse effect or any change in the general condition of the model animals' health, while macroscopy and histology studies identified no changes in the internal organs of the BALB/c mice and rats. This study has demonstrated that a double immunization enhances the growth of antibody titers as assessed by the microneutralization assay (MNA) and the enzyme-linked immunosorbent assay (ELISA) in a pre-clinical immunogenicity test on animal models. The best GMT results were assessed in MNA and ELISA 7 days after re-vaccination; however, we noted that GMT antibody results in ELISA were lower than in MNA. A comparative GMT assessment after the first immunization and the re-immunization identified significant differences between model animal groups and a growth of GMT antibodies in all of them; also, differences between the gender groups were statistically significant. Moreover, the most marked MNA immune response to the QazCovid-in® vaccine was seen in the Syrian hamsters, while their SARS-CoV-2-specific antibody activity as assessed with ELISA was the lowest.

Stopping pandemics before they start: Lessons learned from SARS-CoV-2

The vaccine and drug discovery responses to COVID-19 have worked far better than could have been imagined. Yet by the end of 2021, more than 5 million people had died, and the pandemic continues to evolve and rage globally. This Review will describe how each of the vaccines, antibody therapies, and antiviral drugs that have been approved to date were built on decades of investment in technology and basic science. We will caution that the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus has so far proven a straightforward test of our pandemic preparedness, and we will recommend steps we should undertake now to prepare for, to minimize the effects of, and ideally to prevent future pandemics. Other Reviews in this series describe the interactions of SARS-CoV-2 with the immune system and those therapies that target the host response to infection.

Anti-inflammatory effects of GLP-1 in patients with COVID-19

Introduction

Understanding the pathogenesis and risk factors to control the coronavirus disease 2019 (COVID-19) is necessary. Due to the importance of the inflammatory pathways in the pathogenesis of COVID-19 patients, evaluating the effects of anti-inflammatory medications is important. Glucagon-like peptide 1 receptor agonist (GLP-1 RA) is awell-known glucose-lowering agent with anti-inflammatory effects.

Areas covered

Resources were extracted from the PubMed database, using keywords such as glucagon-like peptide-1, GLP-1 RA, SARS-CoV-2, COVID-19, inflammation, in April2021. In this review, the effects of GLP-1RA in reducing inflammation and modifying risk factors of COVID-19 severe complications are discussed. However, GLP-1 is degraded by DPP-4 with aplasma half-life of about 2–5 minutes, which makes it difficult to measure GLP-1 plasma level in clinical settings.

Expert opinion

Since no definitive treatment is available for COVID-19 so far, determining promising targets to design and/or repurpose effective medications is necessary.

Statin use and mortality in COVID-19 patients: Updated systematic review and meta-analysis

BACKGROUND AND AIMS

Statin therapy is administered to patients with high cardiovascular risk. These patients are also at risk for severe course of coronavirus disease 2019 (COVID-19). Statins exhibit not only cardioprotective but also immunomodulatory and anti-inflammatory effects. This study performed a systematic review of published evidence regarding statin treatment and COVID-19 related mortality.

METHODS

A systematic PubMed/Embase search was performed from February 10, 2020 until March 05, 2021 for studies in COVID-19 patients that reported adjusted hazard or odds ratio for death in statin users versus non-users.

RESULTS

22 studies fulfilled the inclusion criteria and were included in the systematic review. Meta-analysis of 10 studies (n = 41,807, weighted age 56 ± 8 years, men 51%, hypertension 34%, diabetes 21%, statin users 14%) that reported adjusted hazard ratios for mortality in statin users versus non-users showed pooled estimate at 0.65 (95% confidence intervals [CI] 0.53, 0.81). Meta-analysis of 6 studies that reported continuation of statin therapy during hospitalization (58-100% of patients) revealed a pooled hazard ratio of 0.54 (95% CI 0.47, 0.62). Meta-analysis of 12 studies (n = 72,881, weighted age 65 ± 2 years, men 54%, hypertension 66%, diabetes 43%, statin users 30%) that reported adjusted odds ratios for mortality showed pooled estimate at 0.65 (95% CI 0.55, 0.78). Multivariable meta-regression analysis did not reveal any significant association of hazard or odds ratios with anthropometric characteristics or comorbidities.

CONCLUSIONS

This meta-analysis of retrospective observational studies showed that statin therapy was associated with an about 35% decrease in the adjusted risk of mortality in hospitalized COVID-19 patients.

The effect of coincidental SARS-CoV-2 infection on pre-operative cardiopulmonary exercise testing

This case report demonstrates the significant impact active infection with SARS-CoV-2 can have on functional capacity evaluated by cardiopulmonary exercise testing, even in minimally symptomatic individuals. A 75-year-old man underwent cardiopulmonary exercise testing before a right hemicolectomy; SARS-CoV-2 was incidentally diagnosed following his test. The patient underwent a period of isolation and recovery before a second pre-operative cardiopulmonary exercise test 6 weeks later. His resting pulmonary function tests did not vary between tests but his peak work, anaerobic threshold, oxygen pulse, pulse oximetry nadir, ventilation perfusion matching and heart rate response to exercise all improved significantly after this recovery period. These are unique results that add to the existing knowledge of the pathophysiology and management of SARS-CoV-2 in the peri-operative setting. While our patient demonstrated dramatic improvement in his functional capacity following 6 weeks of recovery, he remained in a high-risk group for surgery according to our local guidelines. Cardiopulmonary exercise testing has a valuable role in individualised risk assessment and shared decision-making in complex, urgent surgical cases where the benefits of delaying surgery to recover from SARS-CoV-2 infection should be balanced against the potential risks.

Expert consensus statements for the management of COVID-19-related acute respiratory failure using a Delphi method

BACKGROUND

Coronavirus disease 2019 (COVID-19) pandemic has caused unprecedented pressure on healthcare system globally. Lack of high-quality evidence on the respiratory management of COVID-19-related acute respiratory failure (C-ARF) has resulted in wide variation in clinical practice.

METHODS

Using a Delphi process, an international panel of 39 experts developed clinical practice statements on the respiratory management of C-ARF in areas where evidence is absent or limited. Agreement was defined as achieved when > 70% experts voted for a given option on the Likert scale statement or > 80% voted for a particular option in multiple-choice questions. Stability was assessed between the two concluding rounds for each statement, using the non-parametric Chi-square (χ²) test (p < 0·05 was considered as unstable).

RESULTS

Agreement was achieved for 27 (73%) management strategies which were then used to develop expert clinical practice statements. Experts agreed that COVID-19-related acute respiratory distress syndrome (ARDS) is clinically similar to other forms of ARDS. The Delphi process yielded strong suggestions for use of systemic corticosteroids for critical COVID-19; awake self-proning to improve oxygenation and high flow nasal oxygen to potentially reduce tracheal intubation; non-invasive ventilation for patients with mixed hypoxemic-hypercapnic respiratory failure; tracheal intubation for poor mentation, hemodynamic instability or severe hypoxemia; closed suction systems; lung protective ventilation; prone ventilation (for 16-24 h per day) to improve oxygenation; neuromuscular blocking agents for patient-ventilator dyssynchrony; avoiding delay in extubation for the risk of reintubation; and similar timing of tracheostomy as in non-COVID-19 patients. There was no agreement on positive end expiratory pressure titration or the choice of personal protective equipment.

CONCLUSION

Using a Delphi method, an agreement among experts was reached for 27 statements from which 20 expert clinical practice statements were derived on the respiratory management of C-ARF, addressing important decisions for patient management in areas where evidence is either absent or limited.

TRIAL REGISTRATION

The study was registered with Clinical trials.gov Identifier: NCT04534569.

Expert consensus statements for the management of COVID-19-related acute respiratory failure using a Delphi method

BACKGROUND

Coronavirus disease 2019 (COVID-19) pandemic has caused unprecedented pressure on healthcare system globally. Lack of high-quality evidence on the respiratory management of COVID-19-related acute respiratory failure (C-ARF) has resulted in wide variation in clinical practice.

METHODS

Using a Delphi process, an international panel of 39 experts developed clinical practice statements on the respiratory management of C-ARF in areas where evidence is absent or limited. Agreement was defined as achieved when > 70% experts voted for a given option on the Likert scale statement or > 80% voted for a particular option in multiple-choice questions. Stability was assessed between the two concluding rounds for each statement, using the non-parametric Chi-square (χ²) test (p < 0·05 was considered as unstable).

RESULTS

Agreement was achieved for 27 (73%) management strategies which were then used to develop expert clinical practice statements. Experts agreed that COVID-19-related acute respiratory distress syndrome (ARDS) is clinically similar to other forms of ARDS. The Delphi process yielded strong suggestions for use of systemic corticosteroids for critical COVID-19; awake self-proning to improve oxygenation and high flow nasal oxygen to potentially reduce tracheal intubation; non-invasive ventilation for patients with mixed hypoxemic-hypercapnic respiratory failure; tracheal intubation for poor mentation, hemodynamic instability or severe hypoxemia; closed suction systems; lung protective ventilation; prone ventilation (for 16-24 h per day) to improve oxygenation; neuromuscular blocking agents for patient-ventilator dyssynchrony; avoiding delay in extubation for the risk of reintubation; and similar timing of tracheostomy as in non-COVID-19 patients. There was no agreement on positive end expiratory pressure titration or the choice of personal protective equipment.

CONCLUSION

Using a Delphi method, an agreement among experts was reached for 27 statements from which 20 expert clinical practice statements were derived on the respiratory management of C-ARF, addressing important decisions for patient management in areas where evidence is either absent or limited.

TRIAL REGISTRATION

The study was registered with Clinical trials.gov Identifier: NCT04534569.