South Indian medicinal plants can combat deadly viruses along with COVID-19? - A review

Phytomedical compounds as promising therapeutic agents for COVID-19 targeting angiotensin-converting enzyme 2: a review

AIMS

The aim of the present review was to highlight natural product investigations in silico and in vitro to find plants and chemicals that inhibit or stimulate angiotensin-converting enzyme 2 (ACE-2).

BACKGROUND

The global reduction of incidents and fatalities attributable to infections with SARS-CoV-2 is one of the most public health problems. In the absence of specific therapy for coronavirus disease 2019 (COVID-19), phytocompounds generated from plant extracts may be a promising strategy worth further investigation, motivating researchers to evaluate the safety and anti-SARS-CoV-2 effectiveness of these ingredients.

OBJECTIVE

To review phytochemicals in silico for anti-SARS-CoV-2 activity and to assess their safety and effectiveness in vitro and in vivo.

METHODS

The present review was conducted using various scientific databases and studies on anti-SARS-CoV-2 phytochemicals were analyzed and summarized. The results obtained from the in silico screening were subjected to extraction, isolation, and purification. The in vitro studies on anti-SarcoV-2 were also included in this review. In addition, the results of this research were interpreted, analyzed, and documented on the basis of the bibliographic information obtained.

RESULTS

This review discusses recent research on using natural remedies to cure or prevent COVID-19 infection. The literature analysis shows that the various herbal preparations (extracts) and purified compounds can block the replication or entrance of the virus directly to carry out their anti-SARS-CoV-2 effects. It is interesting to note that certain items can prevent SARS-CoV-2 from infecting human cells by blocking the ACE-2 receptor or the serine protease TMPRRS2. Moreover, natural substances have been demonstrated to block proteins involved in the SARS-CoV-2 life cycle, such as papain- or chymotrypsin-like proteases.

CONCLUSION

The natural products may have the potential for use singly or in combination as alternative drugs to treat/prevent COVID-19 infection, including blocking or stimulating ACE-2. In addition, their structures may provide indications for the development of anti-SARS-CoV-2 drugs.

Nigella sativa and its chemical constituents: pre-clinical and clinical evidence for their potential anti-SARS-CoV-2 effects

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused over 500 million reported cases of COVID-19 worldwide with relatively high morbidity and mortality. Although global vaccination drive has helped control the pandemic, the newer variant of the virus still holds the world in ransom. Several medicinal herbs with antiviral properties have been reported, and one such promising herb is Nigella sativa (NS). Recent molecular docking, pre-clinical, and clinical studies have shown that NS extracts may have the potential to prevent the entry of coronaviruses into the host cell as well as to treat and manage COVID-19 symptoms. Several active compounds from NS, such as nigelledine, α-hederin, dithymoquinone (DTQ), and thymoquinone (TQ), have been proposed as excellent ligands to target angiotensin-converting enzyme 2 (ACE2 receptors) and other targets on host cells as well as the spike protein (S protein) on SARS-CoV-2. By binding to these target proteins, these ligands could potentially prevent the binding between ACE2 and S protein. Though several articles have been published on the promising therapeutic role of NS and its constituents against SARS-CoV-2 infection, in this review, we consolidate the published information on NS and SARS-CoV-2, focusing on pre-clinical in silico studies as well as clinical trials reported between 2012 and 2023.

In silico anti-viral assessment of phytoconstituents in a traditional (Siddha Medicine) polyherbal formulation - Targeting Mpro and pan-coronavirus post-fusion Spike protein

Background and aim

Novel nature of the viral pathogen SARS-CoV-2 and the absence of standard drugs for treatment, have been a major challenge to combat this deadly infection. Natural products offer safe and effective remedy, for which traditional ethnic medicine can provide leads. An indigenous poly-herbal formulation, Kabasura Kudineer from Siddha system of medicine was evaluated here using a combination of computational approaches, to identify potential inhibitors against two anti-SARS-CoV-2 targets - post-fusion Spike protein (structural protein) and main protease (Mpro, non-structural protein).

Experimental procedure

We docked 32 phytochemicals from the poly-herbal formulation against viral post-fusion Spike glycoprotein and Mpro followed by molecular dynamics using Schrodinger software. Drug-likeness analysis was performed using machine learning (ML) approach and pkCSM.

Results

The binding affinity of the phytochemicals in Kabasura Kudineer revealed the following top-five bioactives: Quercetin > Luteolin > Chrysoeriol > 5-Hydroxy-7,8-Dimethoxyflavone > Scutellarein against Mpro target, and Gallic acid > Piperlonguminine > Chrysoeriol > Elemol > Piperine against post-fusion Spike protein target. Quercetin and Gallic acid exhibited binding stability in complexation with their respective viral-targets and favourable free energy change as revealed by the molecular dynamics simulations and MM-PBSA analysis. In silico predicted pharmacokinetic profiling of these ligands revealed appropriate drug-likeness properties.

Conclusion

These outcomes provide: (a) potential mechanism for the anti-viral efficacy of the indigenous Siddha formulation, targeting Mpro and post-fusion Spike protein (b) top bioactive lead-molecules that may be developed as natural product-based anti-viral pharmacotherapy and their pleiotropic protective effects may be leveraged to manage co-morbidities associated with COVID-19.

The use of medicinal plants in the prevention of COVID-19 using the Health Belief Model: A survey based on the Iranian population

BACKGROUND

Because of the spread of coronavirus disease 2019 (COVID-19), the preventive measures have increased, such as focusing on the use of medicinal plants in most communities, including Iran. The purpose of this study was to identify the knowledge, attitude, and performance of individuals toward the use of medicinal plants and to identify the predictors of the use of medicinal plants in the prevention of COVID-19.

MATERIALS AND METHODS

This descriptive-analytical study (February-April 2021) was performed on 3840 Iranian men and women aged 20-70 years selected as a multi-stage cluster study. At the first stage, all provinces were divided into five regions: North, South, East, West, and Center. In the second stage, a provincial center and a city were randomly selected from each region (North: Sari, Babol; South: Bushehr, Bandar Genaveh; East: Mashhad, Sabzevar; West: Hamedan, Toisarkan; Center: Yazd, Ardakan). Data were collected by a researcher-made scale based on the Health Belief Model (HBM). Data analysis was performed applying Pearson correlation coefficient, logistic regression, and linear regression.

RESULTS

The results showed that people have relatively high knowledge and positive attitude toward the use of medicinal plants in prevention of COVID-19. The most important reason for positive attitude was the perceived benefits with the mean of 75.06%. Also, half of the people had poor performance. Correlation coefficient showed that the use of medicinal plants with perceived sensitivity (p = 0.000, r = 0.3), perceived benefits (p = 0.012, r = 0.126), perceived barriers (p = 0.000, r = 0.179), and perceived self-efficacy (p = 0.000, r = 0.305) had a significant correlation. The strongest correlation between perceived self-efficacy was observed with the use of herbs in prevention of COVID-19. The HBM constructs can predict 26% of the variance for the use of medicinal plants in the prevention of COVID-19, among which perceived self-efficacy (β = 0.230) was the most powerful predictor.

CONCLUSION

Based on the results, the predictive role of self-efficacy constructs for the use of medicinal plants in prevention of COVID-19 has been confirmed according to the HBM. Therefore, methods of increasing self-efficacy such as training programs and providing appropriate intervention models can be used not only as promoters of using medicinal plants in prevention of COVID-19 but also for improving people's performance in the proper use of medicinal plants.

A comprehensive review on pharmacologic agents, immunotherapies and supportive therapeutics for COVID-19

The emergence of coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has affected many countries throughout the world. As urgency is a necessity, most efforts have focused on identifying small molecule drugs that can be repurposed for use as anti-SARS-CoV-2 agents. Although several drug candidates have been identified using in silico method and in vitro studies, most of these drugs require the support of in vivo data before they can be considered for clinical trials. Several drugs are considered promising therapeutic agents for COVID-19. In addition to the direct-acting antiviral drugs, supportive therapies including traditional Chinese medicine, immunotherapies, immunomodulators, and nutritional therapy could contribute a major role in treating COVID-19 patients. Some of these drugs have already been included in the treatment guidelines, recommendations, and standard operating procedures. In this article, we comprehensively review the approved and potential therapeutic drugs, immune cells-based therapies, immunomodulatory agents/drugs, herbs and plant metabolites, nutritional and dietary for COVID-19.

Association of Different ABO and Rh Blood Groups with the Erythroprotective Effect of Extracts from Navicula incerta and Their Anti-Inflammatory and Antiproliferative Properties

Previous studies have reported that different blood groups are associated with the risk of chronic degenerative diseases that mainly involve inflammation and neoplastic processes. We investigate the relationship between blood groups and the erythroprotective effect of extracts from Navicula incerta against oxidative damage as a proposal to develop drugs designed for people with a specific blood type related to chronic pathology. The study was carried out through the elucidation of the erythroprotective potential, anti-inflammatory and antiproliferative activity of Navicula incerta. Research suggests that the presence or absence of certain blood groups increases or decreases the abilities of certain phytochemicals to inhibit oxidative stress, which is related to the systemic inflammatory response involved in the development of different types of cancer. The pigment-rich extracts from Navicula incerta inhibit ROO•- induced oxidative stress in human erythrocytes on the A RhD+ve antigen without compromising the structure of the cell membrane. This result is very important, since the A antigen is related to the susceptibility of contracting prostate cancer. Similarly, it was possible to inhibit the proliferation of cervical (HeLa) and prostate (PC-3) carcinoma. The combinatorial analysis of different biological activities can help design phytochemicals as new candidates for preventive drugs treating the chronic degenerative diseases associated with a specific blood group.

Scientific production on medicinal plants and their efficacy against Covid-19: A review and scientometric analysis based on VOSviewer

Historically, numerous plants have been used to alleviate various diseases, particularly viral diseases (bronchitis, influenza virus and dengue virus). This review evaluated their therapeutic potential against Covid-19 and mapped the 10 most studied plants during the pandemic. The standardized protocol for systematic reviews (PRISMA-P) was developed in this study. All studies involving medicinal plants and their potential against Covid-19 infection were also considered. Two specific search fields “traditional medicine and Covid-19” and “medicinal plants and Covid-19” with appearance in the title, abstract and keywords were used to search for information. Only papers (review and original) published between 2020 and October 2021 were included. Short communications, letters to the editor, books and book chapters were excluded. A total of 24,046 articles were recorded among the four databases and an increase of 69% in publications for the 2021 search date, a higher percentage compared to the previous year (31%). China was the country with the highest production with 28% (2725 papers). The analysis of variance showed that the number of studies of Nigella sativa L. (1.62 ± 0.21; p = 0.02), Glycyrrhiza glabra L. (1.50 ± 0.32; p = 0.03), Zingiber officinale Roscoe (1.51 ± 0.32; p = 0.03) were statistically significant with respect to the other species. This is probably because these species show compounds with high antiviral spectrum. Despite the pharmacological potential found in medicinal plants, more large-scale clinical trials are still needed to demonstrate the efficacy of phytocompounds against viral diseases.

A concise review of mushrooms antiviral and immunomodulatory properties that may combat against COVID-19

The World Health Organization (WHO) declared COVID-19 as a pandemic on March 11, 2020, because of its widespread transmission and infection rates. The unique severe disease was found in Wuhan, China, since December 2019, and swiftly spread throughout the world. Natural chemicals derived from herbal medicines and medicinal mushrooms provide a significant resource for the development of novel antiviral drugs. Many natural drugs have been proven to have antiviral properties against a variety of virus strains, such as the coronavirus and the herpes simplex virus (HSV).. In this research, successful dietary treatments for different COVID illnesses were compared to potential of mushroom products in its therapy. In Google Scholar, Science Direct, PubMed, and Scopus, search keywords like COVID, COVID-19, SARS, MERS, mushrooms, and their compounds were utilized. In this review of the literature we foucsed popular mushrooms such as Agaricus subrufescens Peck, Agaricus blazei Murill, Cordyceps sinensis (Berk.) Sacc., Ganoderma lucidum (Curtis.) P. Karst., Grifola frondosa (Dicks.) Gray, Hericium erinaceus (Bull.) Pers., Inonotus obliquus (Arch. Ex Pers.) Pilát., Lentinula edodes (Berk.) Pegler, Pleurotus ostreatus (Jacq.) P. Kumm., Poria cocos F.A. Wolf, and Trametes versicolor (L.) Lloyd.,. Changed forms of β-Glucan seem to have a good impact on viral replication suppression and might be used in future studies. However, the results seems terpenoids, lectins, glycoproteins, lentinan, galactomannan, and polysaccharides from mushrooms are promising prophylactic or therapeutic agents against COVID-19.

A Review with Updated Perspectives on the Antiviral Potentials of Traditional Medicinal Plants and Their Prospects in Antiviral Therapy

Exploration of the traditional medicinal plants is essential for drug discovery and development for various pharmacological targets. Various phytochemicals derived from medicinal plants were extensively studied for antiviral activity. This review aims to highlight the role of medicinal plants against viral infections that remains to be the leading cause of human death globally. Antiviral properties of phytoconstituents isolated from 45 plants were discussed for five different types of viral infections. The ability of the plants’ active compounds with antiviral effects was highlighted as well as their mechanism of action, pharmacological studies, and toxicological data on a variety of cell lines. The experimental values, such as IC₅₀, EC₅₀, CC₅₀, ED₅₀, TD₅₀, MIC₁₀₀, and SI of the active compounds, were compiled and discussed to determine their potential. Among the plants mentioned, 11 plants showed the most promising medicinal plants against viral infections. Sambucus nigra and Clinacanthus nutans manifested antiviral activity against three different types of viral infections. Echinacea purpurea, Echinacea augustofolia, Echinacea pallida, Plantago major, Glycyrrhiza uralensis, Phyllanthus emblica, Camellia sinensis, and Cistus incanus exhibited antiviral activity against two different types of viral infections. Interestingly, Nicotiana benthamiana showed antiviral effects against mosquito-borne infections. The importance of phenolic acids, alkamides, alkylamides, glycyrrhizin, epicatechin gallate (ECG), epigallocatechin gallate (EGCG), epigallocatechin (EGC), protein-based plant-produced ZIKV Envelope (PzE), and anti-CHIKV monoclonal antibody was also reviewed. An exploratory approach to the published literature was conducted using a variety of books and online databases, including Scopus, Google Scholar, ScienceDirect, Web of Science, and PubMed Central, with the goal of obtaining, compiling, and reconstructing information on a variety of fundamental aspects, especially regarding medicinal plants. This evaluation gathered important information from all available library databases and Internet searches from 1992 to 2022.

In-silico screening of naturally derived phytochemicals against SARS-CoV Main protease

Coronavirus disease 2019 (COVID-19) is a rapidly growing pandemic that requires urgent therapeutic intervention. Finding potential anti COVID-19 drugs aside from approved vaccines is progressively going on. The chemically diverse natural products represent valuable sources for drug leads. In this study, we aimed to find out safe and effective COVID-19 protease inhibitors from a library of natural products which share the main nucleus/skeleton of FDA-approved drugs that were employed in COVID-19 treatment guidelines or repurposed by previous studies. Our library was subjected to virtual screening against SARS-CoV Main protease (Mpro) using Molecular Operating Environment (MOE) software. Twenty-two out of those natural candidates showed higher binding scores compared to their analogues. We repurpose these natural products including alkaloids, glucosinolates, and phenolics as potential platforms for the development of anti-SARS-CoV-2 therapeutics. This study paves the way towards discovering a lead used in the treatment of COVID-19 from natural sources and introduces phytomedicines with dual therapeutic effects against COVID-19 besides their original pharmacological effects. We recommend further in vitro evaluation of their anti-COVID-19 activity and future clinical studies.

Antiviral Plants from Marajó Island, Brazilian Amazon: A Narrative Review

Diseases caused by viruses are a global threat, resulting in serious medical and social problems for humanity. They are the main contributors to many minor and major outbreaks, epidemics, and pandemics worldwide. Over the years, medicinal plants have been used as a complementary treatment in a range of diseases. In this sense, this review addresses promising antiviral plants from Marajó island, a part of the Amazon region, which is known to present a very wide biodiversity of medicinal plants. The present review has been limited to articles and abstracts available in Scopus, Web of Science, Science Direct, Scielo, PubMed, and Google Scholar, as well as the patent offices in Brazil (INPI), United States (USPTO), Europe (EPO) and World Intellectual Property Organization (WIPO). As a result, some plants from Marajó island were reported to have actions against HIV-1,2, HSV-1,2, SARS-CoV-2, HAV and HBV, Poliovirus, and influenza. Our major conclusion is that plants of the Marajó region show promising perspectives regarding pharmacological potential in combatting future viral diseases.

Screening of potential inhibitors of COVID-19 with repurposing approach via molecular docking

SARS-CoV-2 (COVID-19) is the causative organism for a pandemic disease with a high rate of infectivity and mortality. In this study, we aimed to assess the affinity between several available small molecule and proteins, including Abl kinase inhibitors, Janus kinase inhibitor, dipeptidyl peptidase 4 inhibitors, RNA-dependent RNA polymerase inhibitors, and Papain-like protease inhibitors, using binding simulation, to test whether they may be effective in inhibiting COVID-19 infection through several mechanisms. The efficiency of inhibitors was evaluated based on docking scores using AutoDock Vina software. Strong ligand-protein interactions were predicted among some of these drugs, that included: Imatinib, Remdesivir, and Telaprevir, and this may render these compounds promising candidates. Some candidate drugs might be efficient in disease control as potential inhibitors or lead compounds against the SARS-CoV-2. It is also worth highlighting the powerful immunomodulatory role of other drugs, such as Abivertinib that inhibits pro-inflammatory cytokine production associated with cytokine release syndrome (CRS) and the progression of COVID-19 infection. The potential role of other Abl kinase inhibitors, including Imatinib in reducing SARS-CoV and MERS-CoV viral titers, immune regulatory function and the development of acute respiratory distress syndrome (ARDS), indicate that this drug may be useful for COVID-19, as the SARS-CoV-2 genome is similar to SARS-CoV.

A comprehensive review on efficient approaches for combating coronaviruses

Almost 80% of people confronting COVID-19 recover from COVID-19 disease without any particular treatments. They experience heterogeneous symptoms; a wide range of respiratory symptoms, cough, dyspnea, fever, and viral pneumonia. However, some others need urgent intervention and special treatment to get rid of this widespread disease. So far, there isn't any unique drug for the potential treatment of COVID 19. However, some available therapeutic drugs used for other diseases seem beneficial for the COVID-19 treatment. On the other hand, there is a robust global concern for developing an efficient COVID-19 vaccine to control the COVID-19 pandemic sustainably. According to the WHO report, since 8 October 2021, 320 vaccines have been in progress. 194 vaccines are in the pre-clinical development stage that 126 of them are in clinical progression. Here, in this paper, we have comprehensively reviewed the most recent and updated information about coronavirus and its mutations, all the potential therapeutic approaches for treating COVID-19, developed diagnostic systems for COVID- 19 and the available COVID-19 vaccines and their mechanism of action.

Possible role of Unani Pharmacology in COVID-19 - a narrative review

According to the World Health Organization (WHO), viral diseases continue to rise, and pose a significant public health problem. Novel coronavirus disease (COVID-19) is an infectious disease caused by SARS-CoV-2. The pathogenesis and clinical manifestations of COVID-19 is close to Amraz-e-Wabai (epidemic diseases) which was described by Hippocrates, Galen, Aristotle, Razes, Haly Abbas, Avicenna, Jurjani etc. Presently, there is no specific or challenging treatment available for COVID-19. Renowned Unani Scholars recommended during epidemic situation to stay at home, and fumigate the shelters with aromatics herbs like Ood kham (Aquilaria agallocha Roxb.), Kundur (Boswellia serrata Roxb), Kafoor (Cinnamomum camphora L.), Sandal (Santalum album L), Hing (Ferula foetida L.) etc. Use of specific Unani formulations are claimed effective for the management of such epidemic or pandemic situation like antidotes (Tiryaqe Wabai, Tiryaqe Arba, Tiryaqe Azam, Gile Armani), Herbal Decoction (Joshandah), along with Sharbate Khaksi, Habbe Bukhar, Sharbate Zanjabeel, Khamira Marwareed, Jawarish Jalinus, and Sirka (vinegar). Such drugs are claimed for use as antioxidant, immunomodulatory, cardiotonic, and general tonic actions. The study enumerates the literature regarding management of epidemics in Unani medicine and attempts to look the same in the perspective of COVID-19 prevention and management.

Comprehensive analysis of SARS-COV-2 drug targets and pharmacological aspects in treating the COVID-19

Corona viruses are enveloped, single-stranded RNA (Ribonucleic acid) viruses and they cause pandemic diseases having a devastating effect on both human healthcare and the global economy. To date, six corona viruses have been identified as pathogenic organisms which are significantly responsible for the infection and also cause severe respiratory diseases. Among them, the novel SARS-CoV-2 (Severe acute respiratory syndrome coronavirus 2) caused a major outbreak of corona virus diseases 2019 (COVID-19). Coronaviridae family members can affects both humans and animals. In human, corona viruses cause severe acute respiratory syndrome with mild to severe outcomes. Several structural and genomics have been investigated, and the genome encodes about 28 proteins most of them with unknown function though it shares remarkable sequence identity with other proteins. There is no potent and licensed vaccine against SARS-CoV-2 and several trials are underway to investigate the possible therapeutic agents against viral infection. However, some of the antiviral drugs that have been investigated against SARS-CoV-2 are under clinical trials. In the current review we comparatively emphasize the emergence and pathogenicity of the SARS-CoV-2 and their infection and discuss the various putative drug targets of both viral and host receptors for developing effective vaccines and therapeutic combinations to overcome the viral outbreak.

Potent phytochemicals against COVID-19 infection from phyto-materials used as antivirals in complementary medicines: a review

Background

Following the outbreak of the COVID-19 pandemic, there was a surge of research activity to find methods/drugs to treat it. There has been drug-repurposing research focusing on traditional medicines. Concomitantly, many researchers tried to find in silico evidence for traditional medicines. There is a great increase in article publication to commensurate the new-found research interests. This situation inspired the authors to have a comprehensive understanding of the multitude of publications related to the COVID-19 pandemic with a wish to get promising drug leads.

Main body

This review article has been conceived and made as a hybrid of the review of the selected papers advertised recently and produced in the interest of the COVID-19 situation, and in silico work done by the authors. The outcome of the present review underscores a recommendation for thorough MDS analyses of the promising drug leads. The inclusion of in silico work as an addition to the review was motivated by a recently published article of Toelzer and colleagues. The in silico investigation of free fatty acids is novel to the field and it buttresses the further MDS analysis of drug leads for managing the COVID-19 pandemic.

Conclusion

The review performed threw light on the need for MDS analyses to be considered together with the application of other in silico methods of prediction of pharmacologic properties directing towards the sites of drug-receptor regulation. Also, the present analysis would help formulate new recipes for complementary medicines.

Use of Natural Compounds as a Potential Therapeutic Agent Against COVID-19

The current 2019-nCoV outbreak is becoming extremely harmful and has affected the whole world. Its control is challenging because there is no effective vaccine or drug available for coronavirus disease. The Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), previously named as 2019 novel coronavirus (2019-nCoV), primarily targets the human respiratory system to lung lesions and lethal pneumonia. Natural products have always shown a crucial role in the process of drug development against various diseases. They may serve as leads for further drug development to combat emergent mutants of the coronavirus. In this review, the current status of natural compounds and their derivatives acting against different species of CoV are discussed.

Medicinal Plants and Isolated Molecules Demonstrating Immunomodulation Activity as Potential Alternative Therapies for Viral Diseases Including COVID-19

Plants have been extensively studied since ancient times and numerous important chemical constituents with tremendous therapeutic potential are identified. Attacks of microorganisms including viruses and bacteria can be counteracted with an efficient immune system and therefore, stimulation of body’s defense mechanism against infections has been proven to be an effective approach. Polysaccharides, terpenoids, flavonoids, alkaloids, glycosides, and lactones are the important phytochemicals, reported to be primarily responsible for immunomodulation activity of the plants. These phytochemicals may act as lead molecules for the development of safe and effective immunomodulators as potential remedies for the prevention and cure of viral diseases. Natural products are known to primarily modulate the immune system in nonspecific ways. A number of plant-based principles have been identified and isolated with potential immunomodulation activity which justify their use in traditional folklore medicine and can form the basis of further specified research. The aim of the current review is to describe and highlight the immunomodulation potential of certain plants along with their bioactive chemical constituents. Relevant literatures of recent years were searched from commonly employed scientific databases on the basis of their ethnopharmacological use. Most of the plants displaying considerable immunomodulation activity are summarized along with their possible mechanisms. These discussions shall hopefully elicit the attention of researchers and encourage further studies on these plant-based immunomodulation products as potential therapy for the management of infectious diseases, including viral ones such as COVID-19.

Medicinal Plants, Phytochemicals, and Herbs to Combat Viral Pathogens Including SARS-CoV-2

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome corona virus-2 (SARS-CoV-2), is the most important health issue, internationally. With no specific and effective antiviral therapy for COVID-19, new or repurposed antiviral are urgently needed. Phytochemicals pose a ray of hope for human health during this pandemic, and a great deal of research is concentrated on it. Phytochemicals have been used as antiviral agents against several viruses since they could inhibit several viruses via different mechanisms of direct inhibition either at the viral entry point or the replication stages and via immunomodulation potentials. Recent evidence also suggests that some plants and its components have shown promising antiviral properties against SARS-CoV-2. This review summarizes certain phytochemical agents along with their mode of actions and potential antiviral activities against important viral pathogens. A special focus has been given on medicinal plants and their extracts as well as herbs which have shown promising results to combat SARS-CoV-2 infection and can be useful in treating patients with COVID-19 as alternatives for treatment under phytotherapy approaches during this devastating pandemic situation.

A Scoping Insight on Potential Prophylactics, Vaccines and Therapeutic Weaponry for the Ongoing Novel Coronavirus (COVID-19) Pandemic- A Comprehensive Review

The emergence of highly virulent CoVs (SARS-CoV-2), the etiologic agent of novel ongoing "COVID-19" pandemics has been marked as an alarming case of pneumonia posing a large global healthcare crisis of unprecedented magnitude. Currently, the COVID-19 outbreak has fueled an international demand in the biomedical field for the mitigation of the fast-spreading illness, all through the urgent deployment of safe, effective, and rational therapeutic strategies along with epidemiological control. Confronted with such contagious respiratory distress, the global population has taken significant steps towards a more robust strategy of containment and quarantine to halt the total number of positive cases but such a strategy can only delay the spread. A substantial number of potential vaccine candidates are undergoing multiple clinical trials to combat COVID-19 disease, includes live-attenuated, inactivated, viral-vectored based, sub-unit vaccines, DNA, mRNA, peptide, adjuvant, plant, and nanoparticle-based vaccines. However, there are no licensed anti-COVID-19 drugs/therapies or vaccines that have proven to work as more effective therapeutic candidates in open-label clinical trial studies. To counteract the infection (SARS-CoV-2), many people are under prolonged treatment of many chemical drugs that inhibit the PLpro activity (Ribavirin), viral proteases (Lopinavir/Ritonavir), RdRp activity (Favipiravir, Remdesivir), viral membrane fusion (Umifenovir, Chloroquine phosphate (CQ), Hydroxychloroquine phosphate (HCQ), IL-6 overexpression (Tocilizumab, Siltuximab, Sarilumab). Mesenchymal Stem Cell therapy and Convalescent Plasma Therapy have emerged as a promising therapeutic strategy against SARS-CoV-2 virion. On the other hand, repurposing previously designed antiviral agents with tolerable safety profile and efficacy could be the only promising approach and fast response to the novel virion. In addition, research institutions and corporations have commenced the redesign of the available therapeutic strategy to manage the global crisis. Herein, we present succinct information on selected anti-COVID-19 therapeutic medications repurposed to combat SARS-CoV-2 infection. Finally, this review will provide exhaustive detail on recent prophylactic strategies and ongoing clinical trials to curb this deadly pandemic, outlining the major therapeutic areas for researchers to step in.

Immunotherapies and immunomodulatory approaches in clinical trials - a mini review

The coronavirus disease (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has created havoc worldwide. Due to the non-availability of any vaccine or drugs against COVID-19, immunotherapies involving convalescent plasma, immunoglobulins, antibodies (monoclonal or polyclonal), and the use of immunomodulatory agents to enhance immunity are valuable alternative options. Cell-based therapies including natural killer cells, T cells, stem cells along with cytokines and toll-like receptors (TLRs) based therapies are also being exploited potentially against COVID-19. Future research need to strengthen the field of developing effective immunotherapeutics and immunomodulators with a thrust of providing appropriate, affordable, convenient, and cost-effective prophylactic and treatment regimens to combat global COVID-19 crisis that has led to a state of medical emergency enforcing entire countries of the world to devote their research infrastructure and manpower in tackling this pandemic.

Identification of Small Molecule Inhibitors of the Deubiquitinating Activity of the SARS-CoV-2 Papain-Like Protease: in silico Molecular Docking Studies and in vitro Enzymatic Activity Assay

COVID-19 is an ongoing pandemic caused by the SARS-CoV-2 virus with important political, socio-economic, and public health consequences. Inhibiting replication represents an important antiviral approach, and in this context two viral proteases, the SARS-CoV-2 main and papain-like proteases (PLpro), which cleave pp1a and pp1ab polypeptides, are critical. Along with protease activity, the PLpro possesses deubiquitinating activity, which is important in immune regulation. Naphthalene-based inhibitors, such as the well-investigated GRL-0617 compound, have been shown to possess dual effects, inhibiting both protease and deubiquitinating activity of the PLpro. Rather than binding to the canonical catalytic triad, these type of non-covalent inhibitors target an adjacent pocket, the naphthalene-inhibitor binding site. Using a high-throughput screen, we have previously identified the dietary hypericin, rutin, and cyanidin-3-O-glucoside compounds as potential protease inhibitors targeting the naphthalene-inhibitor binding site. Here, our aim was to investigate the binding characteristics of these compounds to the PLpro, and to evaluate deubiquitinating activity, by analyzing seven different PLpro crystal structures. Molecular docking highlighted the relatively high affinity of GRL-0617 and dietary compounds. In contrast binding of the small molecules was abolished in the presence of ubiquitin in the palm subdomain of the PLpro. Further, docking the small molecules in the naphthalene-inhibitor binding site, followed by protein-protein docking revealed displacement of ubiquitin in a conformation inconsistent with functional activity. Finally, the deubiquitinating activity was validated in vitro using an enzymatic activity assay. The findings indicated that the dietary compounds inhibited deubiquitinase activity in the micromolar range with an order of activity of GRL-0167, hypericin >> rutin, cyanidin-3-O-glucoside > epigallocatechin gallate, epicatechin gallate, and cefotaxime. Our findings are in accordance with mechanisms and potential antiviral effects of the naphthalene-based, GRL-0617 inhibitor, which is currently progressing in preclinical trials. Further, our findings indicate that in particular hypericin, rutin, and cyanidin-3-O-glucoside, represent suitable candidates for subsequent evaluation as PLpro inhibitors.

In Search of Herbal Anti-SARS-Cov2 Compounds

On March 11, 2020, the World Health Organization (WHO) announced that the spread of the new coronavirus had reached the stage of a pandemic. To date (23.10.2020), there are more than 40 million confirmed cases of the disease in the world, at the same time there is still no effective treatment for the disease. For management and treatment of SARS-Cov2, the development of an antiviral drug is needed. Since the representatives of all human cultures have used medicinal plants to treat viral diseases throughout their history, plants can be considered as sources of new antiviral drug compounds against emerging viruses. The huge metabolic potential of plants allows us to expect discovery of plant compounds for the prevention and treatment of coronavirus infection. This idea is supported by number of papers on the anti-SARS-Cov2 activity of plant extracts and specific compounds in the experiments in silico, in vitro, and in vivo. Here, we summarize information on methods and approaches aimed to search for anti-SARS-Cov2 compounds including cheminformatics, bioinformatics, genetic engineering of viral targets, interacting with drugs, biochemical approaches etc. Our mini-review may be useful for better planning future experiments (including rapid methods for screening compounds for antiviral activity, the initial assessment of the antiviral potential of various plant species in relation to certain pathogens, etc.) and giving a hand to those who are making first steps in this field.

Herbal approach for the management of C0VID-19: an overview

COVID-19 is the most recently discovered coronavirus infectious disease and leads to pandemic all over the world. The clinical continuum of COVID-19 varies from mild illness with non-specific signs and symptoms of acute respiratory disease to extreme respiratory pneumonia and septic shock. It can transmit from animal to human in the form of touch, through the air, water, utensils, fomite and feco-oral route blood. The pathogenesis and clinical features of COVID-19 be the same as the clinical manifestation associated epidemic Fever. In Unani medicine, various herbal drugs are described under the caption of epidemic disease. Great Unani scholar also Avicenna (980-1037 AD) recommended that during epidemic condition movement should be restricted, self-isolation, fumigation around the habitant with perfumed herbs (Ood, Kafoor, Sumbuluttib, Saad Kofi, Loban, etc.), and use of appropriate antidotes (Tiryaqe Wabai) and vinegar (Sirka) as prophylaxis. Herbal approach is based on single (Unnab-Ziziphus jujuba, Sapistan-Cordia myxa, Bahidana-Cydonia oblonga, Khatmi-Althea officinalis, Khubazi-Malva sylvestris, Zafran-Crocus sativus, Sibr-Aloe barbedensis, Murmuki-Commiphora myrrha, Darchini-Cinnamomum zeylanicum, Qaranfal-Syzygium aromaticum, Rihan-Oscimum sanctum, Habtus Sauda-Nigella sativa, Aslus Sus-Glycyrrhiza glabra, Maghze Amaltas-Cassia fistula and Adusa-Adhatoda vasica) and compound drugs (Habbe Bukhar, Sharbat Khaksi, Sharbat Zanjabeel, Naqu Nazla, Majoon Chobchini, Jawrish Jalinus and Khamira Marvareed) most of them are claimed for anti-viral, anti-pyretic, blood purifier, cardioprotective and expectorant activities. Traditionally most of the herbal practitioners are using it.

Use of Nasoil® via intranasal to control the harmful effects of Covid-19

In the absence of vaccines and antiviral drugs available to prevent and treat COVID-19, it becomes imperative to find or use all those products with the potential to fight this virus. This article is an attempt to propose ways to prevent, treat and control the COVID-19 virus, using a product based on plant extracts with the potential to reduce the symptoms caused by the SARS-CoV-2 virus. Nasoil® counts as one of its main components, Asclepias curassavica extracts, and in the present study it has been shown that it is an effective adjuvant in the treatment of Covid-19, increasing the respiratory capacity of the patients (SpO2> 90%) and reducing the symptoms from the first application, improving the patients around the fifth to the eighth application. At a preventive level, the individuals in this study who have applied it (400 individuals) only a 3.15% of these presented symptoms, disappearing when increasing the weekly applications.

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Nasoil® protects from the appearance of symptoms by 96% due to Covid-19.

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Modifying lung microenvironments reduces Covid-19 symptoms.

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Promoting new interactions in the elastic protein decreases the elastase activity of neutrophils.

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The combination of plant extracts in Nasoil® help in respiratory problems.

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Nasoil® is an co-adjuvant for the control and prevention of the SARS-CoV-2 virus.