COVID-19 treatment: Much research and testing, but far, few magic bullets against SARS-CoV-2 coronavirus

How many organic small molecules might be used to treat COVID-19? From natural products to synthetic agents

A large scale of pandemic coronavirus disease (COVID-19) in the past five years motivates a great deal of endeavors donating to the exploration on therapeutic drugs against COVID-19 as well as other diseases caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Herein is an overview on the organic small molecules that are potentially employed to treat COVID-19 and other SARS-CoV-2-related diseases. These organic small molecules are accessed from both natural resources and synthetic strategies. Notably, typical natural products presented herein consist of polyphenols, lignans, alkaloids, terpenoids, and peptides, which exert an advantage for the further discovery of novel anti-COVID-19 drugs from plant herbs. On the other hand, synthetic prodrugs are composed of a series of inhibitors towards RNA-dependent RNA polymerase (RdRp), main protease (Mpro), 3-chymotrypsin-like cysteine protease (3CLpro), spike protein, papain-like protease (PLpro) of the SARS-CoV-2 as well as the angiotensin-converting enzyme 2 (ACE2) in the host cells. Synthetic strategies are worth taken into consideration because they are beneficial for designing novel anti-COVID-19 drugs in the coming investigations. Although examples collected herein are just a drop in the bucket, developments of organic small molecules against coronavirus infections are believed to pave a promising way for the discovery of multi-targeted therapeutic drugs against not only COVID-19 but also other virus-mediated diseases.

Organocatalyzed umpolung addition for synthesis of heterocyclic-fused arylidene-imidazolones as anticancer agents

A strategy of "Nature-to-new" with iterative scaffold-hopping was considered for investigation of privileged ring/functional motif-elaborated analogs of natural aurones. An organocatalyzed umpolung chemistry based method was established for molecular-diversity feasible synthesis of title class of chemotypes i.e. (Z)-2-Arylideneimidazo[1,2-a]pyridinones and (Z)-2-Arylidenebenzo[d]imidazo[2,1-b]thiazol-3-ones. Various biophysical experiments indicated their important biological properties. The analogs showed characteristic anticancer activities with efficiency more than an anticancer drug. The compounds induced apoptosis with arrest in the S phase of the cell cycle regulation. The compounds' significant effect in up/down-regulation of various apoptotic proteins, an apoptosis cascade, and the inhibition of topoisomerases-mediated DNA relaxation process was identified. The analysis of the structure-activity relationship, interference with biological events and the drug-likeness physicochemical properties of the compounds in the acceptable window indicated distinctive medicinal molecule-to-properties of the investigated chemotypes.

Leukotriene Inhibitors with dexamethasone show promise in the prevention of death in COVID-19 patients with low oxygen saturations

Introduction

COVID-19 is a major health threat around the world causing hundreds of millions of infections and millions of deaths. There is a pressing global need for effective therapies. We hypothesized that leukotriene inhibitors (LTIs), that have been shown to lower IL6 and IL8 levels, may have a protective effect in patients with COVID-19.

Methods

In this retrospective controlled cohort study, we compared death rates in COVID-19 patients who were taking a LTI with those who were not taking an LTI. We used the Department of Veterans Affairs (VA) Corporate Data Warehouse (CDW) to create a cohort of COVID-19-positive patients and tracked their use of LTIs between November 1, 2019 and November 11, 2021.

Results

Of the 1,677,595 cohort of patients tested for COVID-19, 189,195 patients tested positive for COVID-19. Forty thousand seven hundred one were admitted. 38,184 had an oxygen requirement and 1214 were taking an LTI. The use of dexamethasone plus a LTI in hospital showed a survival advantage of 13.5% (CI: 0.23%-26.7%; p < 0.01) in patients presenting with a minimal O₂Sat of 50% or less. For patients with an O₂Sat of <60 and <50% if they were on LTIs as outpatients, continuing the LTI led to a 14.4% and 22.25 survival advantage if they were continued on the medication as inpatients.

Conclusions

When combined dexamethasone and LTIs provided a mortality benefit in COVID-19 patients presenting with an O₂ saturations <50%. The LTI cohort had lower markers of inflammation and cytokine storm.

Synthesis, biological and computational studies of flavonoid acetamide derivatives

This study reports the synthesis and characterization of a novel class of flavonoid acetamide derivatives (FA) of quercetin, apigenin, fisetin, kaempferol, and luteolin. Flavonoids display numerous biological properties but are limited by aqueous insolubility, enzymatic degradation, instability, and low bioavailability. FAs were synthesized, with 80-82% yields, through the sequential modification of the flavonoid hydroxyl groups into the acetamide moieties. Bioavailability, antioxidant, and ADMET are structure-activity-dependent properties that vary across different classes of flavonoids and dictate the prevalent biological applications of the flavonoids. Thus, the FAs were evaluated for their bioavailability, antioxidant, and ADMET toxicity properties versus the unmodified flavonoids (UFs). In vitro bioavailability analysis shows that the UFs have bio-availabilities in the range of 10.78-19.29% against that of the FAs in the range of 20.70-34.87%. The antioxidant capacity was measured using the 2,2-diphenyl-1-picrylhydrazyl (DPPH·) assay with recorded IC50 values of 2.19-13.03 μM for the UFs. Conversely, the FAs had high DPPH IC50 values ranging from 33.83 to 67.10 μM and corresponding to lower antioxidant activity. The FAs showed favorable ADMET properties. The modification of flavonoids into FAs significantly improves the bioavailability and the ADMET toxicity properties, albeit with decreased antioxidant activity. This work highlights the effect of the global modification of the flavonoids with the acetamide groups on the bioavailability, antioxidant, and ADMET toxicity properties which are critical determinants in the biological applications of the flavonoids.

Factors Associated with COVID-19 Vaccine Hesitancy in Korea

COVID-19 vaccine hesitancy will likely increase in the unvaccinated general population because of several vaccine safety issues that arose during priority vaccination. To investigate the potential rate of COVID-19 vaccine hesitancy in the unvaccinated population and evaluate factors that affect the attitude towards vaccine acceptance, a cross-sectional survey was performed. A telephone survey was conducted in 1,357 people older than 18 years; 99 were excluded from the analysis because they had already been vaccinated (n=58) or hesitated (n=41) after an official call. The COVID-19 vaccine hesitancy rate was 21.9% and was highest among those aged under 30 years (33.4%) and lowest among those aged 65 years and over (8.7%). Age, occupation, and perceived confidence in vaccine safety and efficacy were associated with vaccine hesitancy. These findings suggest that public health authorities should strengthen the spread of correct information, especially in the younger population, to increase vaccination rates.

Biology of COVID-19 and related viruses: Epidemiology, signs, symptoms, diagnosis, and treatment

Coronaviruses belong to the family Coronaviridae order Nidovirales and are known causes of respiratory and intestinal disease in various mammalian and avian species. Species of coronaviruses known to infect humans are referred to as human coronaviruses (HCoVs). While traditionally, HCoVs have been a significant cause of the common cold, more recently, emergent viruses, including severe acute respiratory syndrome coronavirus (SARS-CoV-2) has caused a global pandemic. Here, we discuss coronavirus disease (COVID-19) biology, pathology, epidemiology, signs and symptoms, diagnosis, treatment, and recent clinical trials involving promising treatments.

Optimization in the Context of COVID-19 Prediction and Control: A Literature Review

This paper presents an overview of some key results from a body of optimization studies that are specifically related to COVID-19, as reported in the literature during 2020-2021. As shown in this paper, optimization studies in the context of COVID-19 have been used for many aspects of the pandemic. From these studies, it is observed that since COVID-19 is a multifaceted problem, it cannot be studied from a single perspective or framework, and neither can the related optimization models. Four new and different frameworks are proposed that capture the essence of analyzing COVID-19 (or any pandemic for that matter) and the relevant optimization models. These are: (i) microscale vs. macroscale perspective; (ii) early stages vs. later stages perspective; (iii) aspects with direct vs. indirect relationship to COVID-19; and (iv) compartmentalized perspective. To limit the scope of the review, only optimization studies related to the prediction and control of COVID-19 are considered (public health focused), and which utilize formal optimization techniques or machine learning approaches. In this context and to the best of our knowledge, this survey paper is the first in the literature with a focus on the prediction and control related optimization studies. These studies include optimization of screening testing strategies, prediction, prevention and control, resource management, vaccination prioritization, and decision support tools. Upon reviewing the literature, this paper identifies current gaps and major challenges that hinder the closure of these gaps and provides some insights into future research directions.

COVID-19 pneumonia: What APRNs should know

ABSTRACT

COVID-19-associated pneumonia is a complex acute care diagnosis that requires careful evaluation and management. This article includes pertinent recommendations for management of acutely ill patients with COVID-19 pneumonia.

Drug repurposing of dermatologic medications to treat coronavirus disease 2019: Science or fiction?

No pharmaceutical products have been demonstrated to be safe and effective to specifically treat coronavirus disease 2019 (COVID-19); therefore, the therapy administered to infected patients remains symptomatic and empiric. Alongside the development of new, often high-cost drugs, a different tactic is being applied in parallel, investigating long-established, inexpensive medications originally designed for a variety of diseases to study their potential in treating COVID-19. The skin is the largest organ of the human body. With more than 3,000 skin conditions identified, the specialty of dermatology offers a rich armamentarium of systemic therapeutic agents aimed to treat the various chronic immunologically mediated, metabolic, infectious, occupational, inherited, or paraneoplastic dermatoses. Dermatologists have extensive experience with many drugs that have demonstrated promising in vitro antiviral action (directly targeting the viral replication). Many of these drugs have been used as nonspecific immunosuppressive strategies, such as glucocorticoids, synthetic antimalarials, colchicine, or other immunomodulators, and a number of targeted therapeutics have been directed at controlling hyperinflammatory processes similar to the "cytokine storm" associated with COVID-19 infection. We discuss several dermatologic drugs that have already been used or may have a promising role in the treatment of COVID-19.

Insights into forsythia honeysuckle (Lianhuaqingwen) capsules: A Chinese herbal medicine repurposed for COVID-19 pandemic

Background

In December 2019, a novel coronavirus, SARS-CoV-2 caused a series of acute atypical respiratory diseases worldwide. However, there is still a lack of drugs with clear curative effects, and the clinical trial research of vaccines has not been completely finished.

Purpose

LH capsules are approved TCM patent medicine that are widely used for the treatment of respiratory tract infectious diseases caused by colds and flu. On April 12, 2020, LH capsules and granules were officially repurposed by the China Food and Drug Administration (CFDA) for patients with mild COVID-19 based on their safety and efficacy demonstrated through multicentre, randomized, controlled clinical trials. We hope to conduct a comprehensive review of it through modern pharmacy methods, and try to explain its possible mechanism.

Methods

Using the full names of LH capsules Lianhuaqingwen, Lianhua Qingwen andSARS-COV-2, COVID-19 as the keywords of the search terms, systemically search for existing related papers in various databases such as Web of Science and PubMed. And completed the collection of clinical data in ClinicalTrials.gov and Chinese Clinical Trial Registry. Last but not least, we have sorted out the anti-inflammatory and antiviral mechanisms of LH capsules through literature and Selleck.

Results

This review systematically sorted out the active ingredients in LH capsules. Furthermore, the related pharmacological and clinical trials of LH capsule on SARS-CoV-2, IAV and IBV were discussed in detail. Moreover, the present review provides the first summary of the potential molecular mechanism of specific substances in LH capsules involved in resistance to SARS-COV-2 infection and the inhibition of cytokine storm syndrome (CSS) caused by IL-6.

Conclusion

This review summarizes the available reports and evidence that support the use of LH capsules as potential drug candidates for the prevention and treatment of COVID-19. However, TCM exerts its effects through multiple targets and multiple pathways, and LH capsules are not an exception. Therefore, the relevant mechanisms need to be further improved and experimentally verified.

Metal-Promoted Heterocyclization: A Heterosynthetic Approach to Face a Pandemic Crisis

The outbreak of SARS-CoV-2 has drastically changed our everyday life and the life of scientists from all over the world. In the last year, the scientific community has faced this worldwide threat using any tool available in order to find an effective response. The recent formulation, production, and ongoing administration of vaccines represent a starting point in the battle against SARS-CoV-2, but they cannot be the only aid available. In this regard, the use of drugs capable to mitigate and fight the virus is a crucial aspect of the pharmacological strategy. Among the plethora of approved drugs, a consistent element is a heterocyclic framework inside its skeleton. Heterocycles have played a pivotal role for decades in the pharmaceutical industry due to their high bioactivity derived from anticancer, antiviral, and anti-inflammatory capabilities. In this context, the development of new performing and sustainable synthetic strategies to obtain heterocyclic molecules has become a key focus of scientists. In this review, we present the recent trends in metal-promoted heterocyclization, and we focus our attention on the construction of heterocycles associated with the skeleton of drugs targeting SARS-CoV-2 coronavirus.

Deciphering the key heterocyclic scaffolds in targeting microtubules, kinases and carbonic anhydrases for cancer drug development

Heterocyclic scaffolds are widely utilized for drug design by taking into account the molecular structure of therapeutic targets that are related to a broad spectrum of ailments, including tumors. Such compounds display various covalent and non-covalent interactions with the specific residues of the target proteins while causing their inhibition. There is a substantial number of heterocyclic compounds approved for cancer treatment, and these compounds function by interacting with different therapeutic targets involved in tumorogenesis. In this review, we trace and emphasize the privileged heterocyclic pharmacophores that have immense potency against several essential chemotherapeutic tumor targets: microtubules, kinases and carbonic anhydrases. Potent compounds currently undergoing pre-clinical and clinical studies have also been assessed for ascertaining the effective class of chemical scaffolds that have significant therapeutic potential against multiple malignancies. In addition, we also describe briefly the role of heterocyclic compounds in various chemotherapy regimens. The optimized molecular hybridization of delineated motifs may result in the discovery of more active anticancer therapeutics and circumvent the development of resistance by specific targets in the future.

The situation of small molecules targeting key proteins to combat SARS-CoV-2: Synthesis, metabolic pathway, mechanism of action, and potential therapeutic applications

Due to the global epidemic and high mortality of 2019 coronavirus disease (COVID-19), there is an immediate need to discover drugs that can help before a vaccine becomes available. Given that the process of producing new drugs is so long, the strategy of repurposing existing drugs is one of the promising options for the urgent treatment of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes COVID-19 disease. Although FDA has approved Remdesivir for the use in hospitalized adults and pediatric patients suffering from COVID-19, no fully effective and reliable drug has been yet identified worldwide to treat COVID-19 specifically. Thus, scientists are still trying to find antivirals specific to COVID-19. This work reviews the chemical structure, metabolic pathway, mechanism of action of existing drugs with potential therapeutic applications for COVID-19. Further, we summarized the molecular docking stimulation of the medications related to key protein targets. These already drugs could be developed for further clinical trials to supply suitable therapeutic options for patients suffering from COVID-19.

The race to treat COVID-19: Potential therapeutic agents for the prevention and treatment of SARS-CoV-2

The unforeseen emergence of coronavirus disease 2019 (COVID-19), a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at the Wuhan province of China in December 2019, subsequently its abrupt spread across the world has severely affected human life. In a short span of time, COVID-19 has sacked more than one million human lives and marked as a severe global pandemic, which is drastically accountable for the adverse effect directly to the human society, particularly the health care system and the economy. The unavailability of approved and effective drugs or vaccines against COVID-19 further created conditions more adverse and terrifying. To win the war against this pandemic within time there is a desperate need for the most adequate therapeutic treatment, which can be achieved by the collaborative research work among scientists worldwide. In continuation of our efforts to support the scientific community, a review has been presented which discusses the structure and the activity of numerous molecules exhibiting promising SARS-CoV-2 and other CoVs inhibition activities. Furthermore, this review offers an overview of the structure, a plausible mechanism of action of SARS-CoV-2, and crucial structural features substantial to inhibit the primary virus-based and host-based targets involved in SARS-CoV-2 treatment. We anticipate optimistically that this perspective will provide the reader and researcher’s better understanding regarding COVID-19 and pave the path in the direction of COVID-19 drug discovery and development paradigm.

Circulating Levels of Calcitonin Gene-Related Peptide Are Lower in COVID-19 Patients

Background

To better understand the biology of COVID-19, we have explored the behavior of calcitonin gene-related peptide (CGRP), an angiogenic, vasodilating, and immune modulating peptide, in severe acute respiratory syndrome coronavirus 2 positive patients.

Methods

Levels of CGRP in the serum of 57 COVID-19 patients (24 asymptomatic, 23 hospitalized in the general ward, and 10 admitted to the intensive care unit) and healthy donors (n = 24) were measured by enzyme-linked immunosorbent assay (ELISA). In addition, to better understand the physiological consequences of the observed variations, we investigated by immunofluorescence the distribution of receptor activity modifying protein 1 (RAMP1), one of the components of the CGRP receptor, in autopsy lung specimens.

Results

CGRP levels were greatly decreased in COVID-19 patients (P < 0.001) when compared to controls, and there were no significant differences due to disease severity, sex, age, or comorbidities. We found that COVID-19 patients treated with proton pump inhibitors had lower levels of CGRP than other patients not taking this treatment (P = 0.001). RAMP1 immunoreactivity was found in smooth muscle cells of large blood vessels and the bronchial tree and in the airways´ epithelium. In COVID-19 samples, RAMP1 was also found in proliferating type II pneumocytes, a common finding in these patients.

Conclusions

The lower levels of CGRP should negatively impact the respiratory physiology of COVID-19 patients due to vasoconstriction, improper angiogenesis, less epithelial repair, and faulty immune response. Therefore, restoring CGRP levels in these patients may represent a novel therapeutic approach for COVID-19.

Inflammatory pathways and potential therapies for COVID-19: A mini review

The public health crisis of the novel coronavirus disease (COVID-19) is alarming since January 2020. COVID-19 genome (SARS-CoV-2) is related to other highly pathogenic coronaviruses SARS-CoV (severe acute respiratory syndrome coronavirus) and MERS-CoV (Middle East respiratory syndrome coronavirus). Amino acid substitutions in some of SARS-CoV-2 proteins resulted in mutations proposing more virulent and contagious properties for this novel virus. Coronavirus penetrates the host cell via endocytosis and once infected, immune responses are triggered to fight against the pathogen. Innate immune response activates major transcription factors to secrete proinflammatory cytokines and type 1 interferon response (T1INF) to induce antiviral immunity. While adaptive immunity initiates cascade of B-cells antibody mediated and T-cells cellular mediate immunities, several mechanisms are raised by SARS-CoV-2 to evade host immune response. Consequently, a surge of proinflammatory cytokines, known as cytokine storm (CS) are released. Failure to manage CS results in several pathological complications as acute respiratory distress syndrome (ARDS). Although researches have not discovered an effective treatment against SARS-CoV-2, recent therapeutic approaches recommending the use of anti-inflammatories in combination with antivirals and some repurposed drugs for COVID-19 patients. Future medications should be designed to target essential hallmarks in the CS to improve clinical outcomes.

Transition metal complexes as potential tools against SARS-CoV-2: anin silicoapproach

Screening of selected transition metal-based antiviral agents,in silico, predicted the potential inhibition of RNA-dependent RNA polymerase (RdRp) of SARS-CoV-2 which emerged as the potential drug candidate for COVID-19.

Treatment of SARS-CoV-2 (COVID-19) cases by the oral administration of montelukast tablets

According to the hypothesis, montelukast may have therapeutic action against severe acute respiratory syndrome (SARS) occurred by coronavirus 2 (CoV-19). The research was aimed to evaluate the therapeutic effects of montelukast tablet on coronavirus infectious disease (COVID-19) patients. A total of 20 COVID-19 confirmed patients were included in this study. The presence of COVID-19 infections in all patients was confirmed using real-time polymerase chain reaction (PCR) and computerized tomography (CT) scan. Confirmed cases were treated with oral administration of montelukast (10 mg) tablet for 10 days. The study population was included 18 to 82 years old patients (10 males and 10 females). The mean age of studied men and women individuals were 44.7±17 and 41±17.45 years, respectively. Frequency of respiratory distress, cough, abdominal cramps/diarrhea, fever, and odor disorder clinical signs amongst the examined patients were 85%, 90%, 20%, 70%, and 65%, respectively. Our findings revealed that all patients who were received 10 days of oral administration of montelukast tablets (10 mg) were recovered from the COVID-19 disease. Additionally, all of the clinical signs of COVID-19 patients, including respiratory distress, cough, and odor disorder, were gradually disappeared. Our findings revealed that widespread oral administration of montelukast tablets (10 mg) is a potential treatment for COVID-19 disease. However, several double-blind and multifactorial clinical trials should perform to determine the other clinical aspects of the treatment of COVID-19 patients by oral administration of montelukast.

N-terminally truncated nucleocapsid protein of SARS-CoV-2 as a better serological marker than whole nucleocapsid protein in evaluating the immunogenicity of inactivated SARS-CoV-2

The coronavirus disease 2019 pandemic caused by severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) had led to a serious public health crisis, and no specific treatments or vaccines are available yet. A nucleocapsid protein (NP)-based enzyme-linked immunosorbent assay (ELISA) detection method is not only important in disease diagnosis, but is required for the evaluation of vaccine efficacy during the development of an inactivated SARS-CoV-2 vaccine. In this study, we expressed both the NP and N-terminally truncated NP (ΔN-NP) of SARS-CoV-2 in an Escherichia coli expression system and described the purification of the soluble recombinant NP and ΔN-NP in details. The identities of the NP and ΔN-NP were confirmed with mass spectrometry. We then used immunoglobulin G detection ELISAs to compare the sensitivity of NP and ΔN-NP in detecting anti-SARS-CoV-2 antibodies. ΔN-NP showed greater sensitivity than NP in the analysis of serially diluted sera from mice and rabbits vaccinated with inactive SARS-CoV-2 and in human sera diluted 1:400. ΔN-NP showed a positive detection rate similar to that of the SARS-CoV-2 S protein in human sera. We conclude that ΔN-NP is a better serological marker than NP for evaluating the immunogenicity of inactivated SARS-CoV-2.