Ellagic acid for COVID-19

This review discusses the prevention and treatment of coronavirus disease 2019 (COVID-19) caused by infection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Mutations in its spike glycoprotein have driven the emergence of variants with high transmissibility and immune escape capabilities. Some antiviral drugs are ineffective against the BA.2 subvariant at the authorized dose. Recently, 150 natural metabolites have been identified as potential candidates for development of new anti-COVID-19 drugs with higher efficacy and lower toxicity than those of existing therapeutic agents. Botanical drug-derived bioactive molecules have shown promise in dampening the COVID-19 cytokine storm and thus preventing pulmonary fibrosis, as they exert a strong binding affinity for viral proteins and inhibit their activity. The Health Ministry of Thailand has approved Andrographis paniculata (Jap. Senshinren) extracts to treat COVID-19. In China, over 85% of patients infected with SARS-CoV-2 receive treatments based on traditional Chinese medicine. A comprehensive map of the stages and pathogenetic mechanisms related to the disease and effective natural products to treat and prevent COVID-19 are presented. Approximately 10% of patients with COVID-19 are affected by long COVID, and COVID-19 infection impairs mitochondrial DNA. As the number of agents to treat COVID-19 is limited, adjuvant botanical drug treatments including vitamin C and E supplementation may reduce COVID-19 symptoms and inhibit progression to long COVID.

Abstract Coronaviruses constitute a significant threat to the human population. Severe acute respiratory syndrome coronavirus-2, SARS-CoV-2, is a highly pathogenic human coronavirus that has caused the coronavirus disease 2019 (COVID-19) pandemic. It has led to a global viral outbreak with an exceptional spread and a high death toll, highlighting the need for effective antiviral strategies. 3-Chymotrypsin-like protease (3CLpro), the main protease in SARS-CoV-2, plays an indispensable role in the SARS-CoV-2 viral life cycle by cleaving the viral polyprotein to produce 11 individual non-structural proteins necessary for viral replication. 3CLpro is one of two proteases that function to produce new viral particles. It is a highly conserved cysteine protease with identical structural folds in all known human coronaviruses. Inhibitors binding with high affinity to 3CLpro will prevent the cleavage of viral polyproteins, thus impeding viral replication. Multiple strategies have been implemented to screen for inhibitors against 3CLpro, including peptide-like and small molecule inhibitors that covalently and non-covalently bind the active site, respectively. In addition, allosteric sites of 3CLpro have been identified to screen for small molecules that could make non-competitive inhibitors of 3CLpro. In essence, this review serves as a comprehensive guide to understanding the structural intricacies and functional dynamics of 3CLpro, emphasizing key findings that elucidate its role as the main protease of SARS-CoV-2. Notably, the review is a critical resource in recognizing the advancements in identifying and developing 3CLpro inhibitors as effective antiviral strategies against COVID-19, some of which are already approved for clinical use in COVID-19 patients.

Objective: This study aims to elucidate the main compounds and mechanisms of action of Empon-empon (EE), a traditional Indonesian herb used for treating COVID-19 and atherosclerosis, utilizing an integrated network pharmacology and molecular docking approach. Methods: Active compounds in EE were obtained through the KNApSAcK, screening active compounds using parameters: oral bioavailability (OB) ≥ 30% and drug-likeness (DL) ≥ 0.18. Compound-related target genes were collected from GeneCard, ChemBL, and Traditional Chinese Medicine Systems Pharmacology (TCMSP). Disease targets were obtained from the GeneCard database. The protein-protein interaction (PPI) network was built using STRING and visualized using Cytoscape. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis using ShinyGO. Molecular docking analysis using Autodock Vina in PyRx. Results: We identified 18 main compounds in EE. PPI analysis obtained 5 central EE targets involved in treating COVID-19 and atherosclerosis, namely E1A Binding Protein P300 (EP300), Heat Shock Protein 90 Alpha Family Class A Member 1 (HSP90AA1), SRC Proto-Oncogene (SRC), Estrogen Receptor 1 (ESR1), and RELA Proto-Oncogene (RELA). GO and KEGG analysis illustrated EE's pharmacological effects through pathways in cancer, lipid and atherosclerosis, and PI3K-Akt signaling, including Coronavirus disease. Catechin and quercetin exhibited the strongest binding affinity to EP300; licarin B and delphinidin to HSP90AA1; epicatechin and delphinidin to SRC; galangin and ellagic acid to ESR1; and guaiacin and licarin B to RELA. Conclusion: This research provides a strong foundation regarding the main compound and mechanism action of EE in treating atherosclerosis and COVID-19, suggesting potential as a novel therapeutic agent.

Abstract The rapid transmission of SARS-CoV-2 and its capability to spread in humans has brought about the development of new approaches for treatment against COVID-19. Drugs and vaccines available currently either target the virus ectodomain or endodomain. Thus, repurposing the use of natural products that target more than one part of the virus is the fastest option available for treatment. Plants are a repository of important constituents with proven significant efficacy against many human viruses. The present study focused on employing computational approaches for screening phytochemicals from 4 Indian medicinal plants, by targeting more than one part of SARS-CoV-2 for the identification of natural antiviral therapeutics to determine their feasibility as potential inhibitors of target viral proteins. Here, we used a multi-target, ligand virtual screening study on 9 target proteins important in SARS-CoV-2 lifecycle, namely Spike glycoprotein, Nucleocapsid phosphatase, Spike protein ACE-2, Non-structural protein 10 and 12, RdRp, Envelope protein, Main protease/3CL protease, and Papain like proteas. Out of the 58 plant phytochemicals screened, Z-5-methyl-6- heneicosen-11- one from Piper nigrum, Arjunetin from Terminalia arjuna, Rutin from Azadirachta indica and Makisterone A from Tinospora cordifolia exhibited highest binding affinity with 9 viral targets. In addition, ADMET analysis indicated Ursodeoxycholic acid, Ellagic Acid, Epicatechin and Isocolumbin, Ecdysterone, Columbin from Piper nigrum, Terminalia arjuna, Azadirachta indica, and Tinospora cordifolia have good binding energetics with the target viral proteins. The research thus enlightens the suitable pharmacological properties and the anti-viral activity of potential medicinal plant molecules for human administration using extensive in-silico techniques.

AbstractCOVID‐19, which was first identified in 2019 in Wuhan, China, is a respiratory illness caused by a virus called severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2). Although some patients infected with COVID‐19 can remain asymptomatic, most experience a range of symptoms that can be mild to severe. Common symptoms include fever, cough, shortness of breath, fatigue, loss of taste or smell and muscle aches. In severe cases, complications can arise including pneumonia, acute respiratory distress syndrome, organ failure and even death, particularly in older adults or individuals with underlying health conditions. Treatments for COVID‐19 include remdesivir, which has been authorised for emergency use in some countries, and dexamethasone, a corticosteroid used to reduce inflammation in severe cases. Biological drugs including monoclonal antibodies, such as casirivimab and imdevimab, have also been authorised for emergency use in certain situations. While these treatments have improved the outcome for many patients, there is still an urgent need for new treatments. Medicinal plants have long served as a valuable source of new drug leads and may serve as a valuable resource in the development of COVID‐19 treatments due to their broad‐spectrum antiviral activity. To date, various medicinal plant extracts have been studied for their cellular and molecular interactions, with some demonstrating anti‐SARS‐CoV‐2 activity in vitro. This review explores the evaluation and potential therapeutic applications of these plants against SARS‐CoV‐2. This review summarises the latest evidence on the activity of different plant extracts and their isolated bioactive compounds against SARS‐CoV‐2, with a focus on the application of plant‐derived compounds in animal models and in human studies.

The SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2019) etiological agent, which has a high contagiousness and is to blame for the outbreak of acute viral pneumonia, is the cause of the respiratory disease COVID-19. The use of natural products grew as an alternative treatment for various diseases due to the abundance of organic molecules with pharmacological properties. Many pharmaceutical studies have focused on investigating compounds with therapeutic potential. Therefore, this study aimed to identify potential antiviral compounds from a popular medicinal plant called Moringa oleifera Lam. against the spike, Mpro, ACE2, and RBD targets of SARS-CoV-2. For this, we use molecular docking to identify the molecules with the greatest affinity for the targets through the orientation of the ligand with the receptor in complex. For the best results, ADME-TOX predictions were performed to evaluate the pharmacokinetic properties of the compounds using the online tool pkCSM. The results demonstrate that among the 61 molecules of M. oleifera, 22 molecules showed promising inhibition results, where the compound ellagic acid showed significant molecular affinity (−9.3 kcal.mol−1) in interaction with the spike protein. These results highlight the relevance of investigating natural compounds from M. oleifera as potential antivirals against SARS-CoV-2; however, additional studies are needed to confirm the antiviral activity of the compounds.

The COVID-19 pandemic has stimulated collaborative drug discovery efforts in academia and the industry with the aim of developing therapies and vaccines that target SARS-CoV-2. Several novel therapies have been approved and deployed in the last three years. However, their clinical application has revealed limitations due to the rapid emergence of viral variants. Therefore, the development of next-generation SARS-CoV-2 therapeutic agents with a high potency and safety profile remains a high priority for global health. Increasing awareness of the “back to nature” approach for improving human health has prompted renewed interest in natural products, especially dietary polyphenols, as an additional therapeutic strategy to treat SARS-CoV-2 patients, owing to its good safety profile, exceptional nutritional value, health-promoting benefits (including potential antiviral properties), affordability, and availability. Herein, we describe the biological properties and pleiotropic molecular mechanisms of dietary polyphenols curcumin, resveratrol, and gossypol as inhibitors against SARS-CoV-2 and its variants as observed in in vitro and in vivo studies. Based on the advantages and disadvantages of dietary polyphenols and to obtain maximal benefits, several strategies such as nanotechnology (e.g., curcumin-incorporated nanofibrous membranes with antibacterial-antiviral ability), lead optimization (e.g., a methylated analog of curcumin), combination therapies (e.g., a specific combination of plant extracts and micronutrients), and broad-spectrum activities (e.g., gossypol broadly inhibits coronaviruses) have also been emphasized as positive factors in the facilitation of anti-SARS-CoV-2 drug development to support effective long-term pandemic management and control.

Covid-19 spreading have caused millions of deaths worldwide and caused sever economic shrinking resulted in high levels of inflations. The on going pandemic has pushed the pharmaceutical companies to invent different vaccines to overcome the spreading of the virus and to reduce its effect on health and economy. Unfortunately, the middle and low income countries have been struggling in providing vaccines to their people due to the high expenses associated with vaccines ordering. Thus, the interest in finding a treatment and a prevention of Covid-19 from natural products has increased not in those countries only, even in high income countries. In this review we investigated the promising natural phytochemical compounds and their published mechanism of action in a prestigious peer-reviewed research journal throw different molecular docking and in vivo and vitro techniques. Its was found that the consumption of the medicinal plants containing small phenolic and terpenoids phytoconstituent like as thymoquinone, quercetin, caffeic acid, ursolic acid, ellagic acid, vanillin, and thymol have a great therapeutic effect for curing and preventing viral infections. This review has focused on the small polyphenolic and terpenoids compounds and their potential and mechanism activity against SARS-CoV-2. Our comprehensive analysis provides mechanistic insight into plant components for virus containment prevent infections and provide better solutions through natural therapeutically active ingredients.

The ongoing COVID-19 pandemic has resulted in a global panic because of its continual evolution and recurring spikes. This serious malignancy is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Since the outbreak, millions of people have been affected from December 2019 till now, which has led to a great surge in finding treatments. Despite trying to handle the pandemic with the repurposing of some drugs, such as chloroquine, hydroxychloroquine, remdesivir, lopinavir, ivermectin, etc., against COVID-19, the SARS-CoV-2 virus continues its out-of-control spread. There is a dire need to identify a new regimen of natural products to combat the deadly viral disease. This article deals with the literature reports to date of natural products showing inhibitory activity towards SARS-CoV-2 through different approaches, such as in vivo, in vitro, and in silico studies. Natural compounds targeting the proteins of SARS-CoV-2—the main protease (Mpro), papain-like protease (PLpro), spike proteins, RNA-dependent RNA polymerase (RdRp), endoribonuclease, exoribonuclease, helicase, nucleocapsid, methyltransferase, adeno diphosphate (ADP) phosphatase, other nonstructural proteins, and envelope proteins—were extracted mainly from plants, and some were isolated from bacteria, algae, fungi, and a few marine organisms.

Pomegranate (Punica granatum L.) is a rich source of polyphenols, including ellagitannins and ellagic acid. The plant is used in traditional medicine, and its purified components can provide anti-inflammatory and antioxidant activity and support of host defenses during viral infection and recovery from disease. Current data show that pomegranate polyphenol extract and its ellagitannin components and metabolites exert their beneficial effects by controlling immune cell infiltration, regulating the cytokine secretion and reactive oxygen and nitrogen species production, and by modulating the activity of the NFκB pathway. In vitro, pomegranate extracts and ellagitannins interact with and inhibit the infectivity of a range of viruses, including SARS-CoV-2. In silico docking studies show that ellagitannins bind to several SARS-CoV-2 and human proteins, including a number of proteases. This warrants further exploration of polyphenol–viral and polyphenol–host interactions in in vitro and in vivo studies. Pomegranate extracts, ellagitannins and ellagic acid are promising agents to target the SARS-CoV-2 virus and to restrict the host inflammatory response to viral infections, as well as to supplement the depleted host antioxidant levels during the stage of recovery from COVID-19.

Natural products and plant extracts exhibit many biological activities, including that related to the defense mechanisms against parasites. Many studies have investigated the biological functions of secondary metabolites and reported evidence of antiviral activities. The pandemic emergencies have further increased the interest in finding antiviral agents, and efforts are oriented to investigate possible activities of secondary plant metabolites against human viruses and their potential application in treating or preventing SARS-CoV-2 infection. In this review, we performed a comprehensive analysis of studies through in silico and in vitro investigations, also including in vivo applications and clinical trials, to evaluate the state of knowledge on the antiviral activities of secondary metabolites against human viruses and their potential application in treating or preventing SARS-CoV-2 infection, with a particular focus on natural compounds present in food plants. Although some of the food plant secondary metabolites seem to be useful in the prevention and as a possible therapeutic management against SARS-CoV-2, up to now, no molecules can be used as a potential treatment for COVID-19; however, more research is needed.

Abstract Due to the lack of a method to efficiently represent the multimodal information of a protein, including its structure and sequence information, predicting compound-protein binding affinity (CPA) still suffers from low accuracy when applying machine-learning methods. To overcome this limitation, in a novel end-to-end architecture (named FeatNN), we develop a coevolutionary strategy to jointly represent the structure and sequence features of proteins and ultimately optimize the mathematical models for predicting CPA. Furthermore, from the perspective of data-driven approach, we proposed a rational method that can utilize both high- and low-quality databases to optimize the accuracy and generalization ability of FeatNN in CPA prediction tasks. Notably, we visually interpret the feature interaction process between sequence and structure in the rationally designed architecture. As a result, FeatNN considerably outperforms the state-of-the-art (SOTA) baseline in virtual drug evaluation tasks, indicating the feasibility of this approach for practical use. FeatNN provides an outstanding method for higher CPA prediction accuracy and better generalization ability by efficiently representing multimodal information of proteins via a coevolutionary strategy.

Drug repurposing requires distinguishing established drug class targets from novel molecule-specific mechanisms and rapidly derisking their therapeutic potential in a time-critical manner, particularly in a pandemic scenario. In response to the challenge to rapidly identify treatment options for COVID-19, several studies reported that statins, as a drug class, reduce mortality in these patients. However, it is unknown if different statins exhibit consistent function or may have varying therapeutic benefit. A Bayesian network tool was used to predict drugs that shift the host transcriptomic response to SARS-CoV-2 infection towards a healthy state. Drugs were predicted using 14 RNA-sequencing datasets from 72 autopsy tissues and 465 COVID-19 patient samples or from cultured human cells and organoids infected with SARS-CoV-2. Top drug predictions included statins, which were then assessed using electronic medical records containing over 4,000 COVID-19 patients on statins to determine mortality risk in patients prescribed specific statins versus untreated matched controls. The same drugs were tested in Vero E6 cells infected with SARS-CoV-2 and human endothelial cells infected with a related OC43 coronavirus. Simvastatin was among the most highly predicted compounds (14/14 datasets) and five other statins, including atorvastatin, were predicted to be active in > 50% of analyses. Analysis of the clinical database revealed that reduced mortality risk was only observed in COVID-19 patients prescribed a subset of statins, including simvastatin and atorvastatin. In vitro testing of SARS-CoV-2 infected cells revealed simvastatin to be a potent direct inhibitor whereas most other statins were less effective. Simvastatin also inhibited OC43 infection and reduced cytokine production in endothelial cells. Statins may differ in their ability to sustain the lives of COVID-19 patients despite having a shared drug target and lipid-modifying mechanism of action. These findings highlight the value of target-agnostic drug prediction coupled with patient databases to identify and clinically evaluate non-obvious mechanisms and derisk and accelerate drug repurposing opportunities.

The first cases of COVID-19, which is caused by the SARS-CoV-2, were reported in December 2019. The vertiginous worldwide expansion of SARS-CoV-2 caused the collapse of health systems in several countries due to the high severity of the COVID-19. In addition to the vaccines, the search for active compounds capable of preventing and/or fighting the infection has been the main direction of research. Since the beginning of this pandemic, some evidence has highlighted the importance of a phenolic-rich diet as a strategy to reduce the progression of this disease, including the severity of the symptoms. Some of these compounds (e.g., curcumin, gallic acid or quercetin) already showed capacity to limit the infection of viruses by inhibiting entry into the cell through its binding to protein Spike, regulating the expression of angiotensin-converting enzyme 2, disrupting the replication in cells by inhibition of viral proteases, and/or suppressing and modulating the host’s immune response. Therefore, this review intends to discuss the most recent findings on the potential of phenolics to prevent SARS-CoV-2.