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1.
Braz J Biol ; 84: e250667, 2022.
Article in English | MEDLINE | ID: covidwho-2231828

ABSTRACT

Nigella sativa is known for the safety profile, containing a wealth of useful antiviral compounds. The main protease (Mpro, 3CLpro) of severe acute respiratory syndrome 2 (SARS-CoV-2) is being considered as one of the most attractive viral target, processing the polyproteins during viral pathogenesis and replication. In the current investigation we analyzed the potency of active component, thymoquinone (TQ) of Nigella sativa against SARS-CoV-2 Mpro. The structures of TQ and Mpro was retrieved from PubChem (CID10281) and Protein Data Bank (PDB ID 6MO3) respectively. The Mpro and TQ were docked and the complex was subjected to molecular dynamic (MD) simulations for a period 50ns. Protein folding effect was analyzed using radius of gyration (Rg) while stability and flexibility was measured, using root means square deviations (RMSD) and root means square fluctuation (RMSF) respectively. The simulation results shows that TQ is exhibiting good binding activity against SARS-CoV-2 Mpro, interacting many residues, present in the active site (His41, Cys145) and also the Glu166, facilitating the pocket shape. Further, experimental approaches are needed to validate the role of TQ against virus infection. The TQ is interfering with pocket maintaining residues as well as active site of virus Mpro which may be used as a potential inhibitor against SARS-CoV-2 for better management of COVID-19.


Subject(s)
COVID-19 Drug Treatment , Nigella sativa , Benzoquinones , Coronavirus 3C Proteases , Cysteine Endopeptidases/chemistry , Cysteine Endopeptidases/metabolism , Nigella sativa/metabolism , SARS-CoV-2 , Viral Proteins/chemistry , Viral Proteins/metabolism
2.
Mini Rev Med Chem ; 22(14): 1847-1875, 2022.
Article in English | MEDLINE | ID: covidwho-2029879

ABSTRACT

Widely consumed worldwide, Nigella sativa (NS) is a medicinal herb commonly used in various alternative medicine systems, such as Unani and Tibb, Ayurveda, and Siddha. Recommended for regular use in Tibb-e-Nabwi (Prophetic Medicine), NS is considered one of the most notable forms of healing medicine in Islamic literature. Thymoquinone (TQ), the main component of the essential oil of NS, has been reported to have many properties, such as antioxidant, anti-inflammatory, antiviral, and antineoplastic. Its chemical structure indicates antiviral potential against many viruses, including the hepatitis C virus, human immunodeficiency virus, and other coronavirus diseases. Interestingly, molecular docking studies have demonstrated that TQ can potentially inhibit the development of the coronavirus disease 2019 (COVID-19) by binding to the receptor site on the transmembrane serine protease 2 (the activator enzyme that attaches the virus to the cell). In addition, TQ has been shown to be effective against cancer cells due to its inhibitory effect by binding to the different regions of MDM2, according to the proposed molecular docking study. Detailed in this review is the origin of TQ, its significance in alternative medicine, pharmacological value, potential as a cancer antiproliferative agent, use against the coronavirus disease 2019 (COVID-19) and for treatment of other diseases.


Subject(s)
COVID-19 Drug Treatment , Nigella sativa , Antiviral Agents/pharmacology , Benzoquinones , Humans , Molecular Docking Simulation , Nigella sativa/chemistry , Oxidative Stress
3.
Curr Pharm Des ; 28(32): 2664-2676, 2022.
Article in English | MEDLINE | ID: covidwho-2009796

ABSTRACT

Heat shock protein 90 (Hsp90) is a chaperone protein that prevents many other proteins from aggregating by folding them in a certain way. Hsp90 consists of three structural domains: N-terminal, middle and C-terminal domains. Hsp90 has many activities in numerous proteins and signaling pathways like chimeric fusion proteins, steroid hormone receptors, tumor suppressor genes, and cell cycle regulatory proteins. The role of Hsp90 is not only in cancer but also in other diseases like COVID-19, leishmaniasis, diabetes, flavi virus, systemic sclerosis, grass carp reovirus, psoriasis, malaria, cardiac fibrosis, and alcohol-related liver diseases. This review is a compilation of the pharmacological profile of Hsp90 inhibitors, problems associated with them, and suggested remedies for the same.


Subject(s)
Benzoquinones , COVID-19 , Humans , Lactams, Macrocyclic , Macrolides , HSP90 Heat-Shock Proteins/metabolism , Cell Cycle Proteins , Steroids , Hormones
4.
Biomed Pharmacother ; 147: 112658, 2022 Mar.
Article in English | MEDLINE | ID: covidwho-1641135

ABSTRACT

The unexpected emergence of the new Coronavirus disease (COVID-19) has affected more than three hundred million individuals and resulted in more than five million deaths worldwide. The ongoing pandemic has underscored the urgent need for effective preventive and therapeutic measures to develop anti-viral therapy. The natural compounds possess various pharmaceutical properties and are reported as effective anti-virals. The interest to develop an anti-viral drug against the novel severe acute respiratory syndrome Coronavirus (SARS-CoV-2) from natural compounds has increased globally. Here, we investigated the anti-viral potential of selected promising natural products. Sources of data for this paper are current literature published in the context of therapeutic uses of phytoconstituents and their mechanism of action published in various reputed peer-reviewed journals. An extensive literature survey was done and data were critically analyzed to get deeper insights into the mechanism of action of a few important phytoconstituents. The consumption of natural products such as thymoquinone, quercetin, caffeic acid, ursolic acid, ellagic acid, vanillin, thymol, and rosmarinic acid could improve our immune response and thus possesses excellent therapeutic potential. This review focuses on the anti-viral functions of various phytoconstituent and alkaloids and their potential therapeutic implications against SARS-CoV-2. Our comprehensive analysis provides mechanistic insights into phytoconstituents to restrain viral infection and provide a better solution through natural, therapeutically active agents.


Subject(s)
Antiviral Agents/therapeutic use , COVID-19 Drug Treatment , Phytochemicals/therapeutic use , Phytotherapy , Alkaloids/therapeutic use , Benzaldehydes/therapeutic use , Benzoquinones/therapeutic use , Caffeic Acids/therapeutic use , Cinnamates/therapeutic use , Depsides/therapeutic use , Ellagic Acid/therapeutic use , Humans , Quercetin/therapeutic use , SARS-CoV-2 , Thymol/therapeutic use , Triterpenes/therapeutic use
5.
Bioorg Chem ; 120: 105587, 2022 03.
Article in English | MEDLINE | ID: covidwho-1620506

ABSTRACT

Inflammation, oxidation, and compromised immunity all increase the dangers of COVID-19, whereas many pharmaceutical protocols may lead to increased immunity such as ingesting from sources containing vitamin E and zinc. A global search for natural remedies to fight COVID-19 has emerged, to assist in the treatment of this infamous coronavirus. Nigella satvia is a world-renowned plant, an esteemed herbal remedy, which can be used as a liquid medicine to increase immunity while decreasing the dangers of acute respiratory distress syndrome. Thymoqinone (TQ), dithymoqinone (DTQ) and thymohydroquinone (THQ), are major compounds of the essential oil contained in N.sativa. A current study aims to discover the antiviral activity of two compounds, Thymohydroquinone and Dithymoquinone, which are synthesized through simple chemical procedures, deriving from thymoquinone, which happens to be a major compound of Nigella sativa. A half-maximal cytotoxic concentration, "CC50", was calculated by MTT assay for each individual drug, The sample showed anti-SARS-CoV-2 activity at non-cytotoxic nanomolar concentrations in vitro with a low selectivity index (CC50/IC50 = 31.74/23.15 = 1.4), whereby Dimthymoquinone shows high cytotoxicity.


Subject(s)
Biological Products , COVID-19 Drug Treatment , Nigella sativa , Severe acute respiratory syndrome-related coronavirus , Antiviral Agents/pharmacology , Antiviral Agents/therapeutic use , Benzoquinones/pharmacology , Nigella sativa/chemistry , Plant Extracts/therapeutic use , Thymol/analogs & derivatives
6.
Virology ; 566: 60-68, 2022 01.
Article in English | MEDLINE | ID: covidwho-1537115

ABSTRACT

The emergence of SARS-CoV-2 virus has resulted in a worldwide pandemic, but effective antiviral therapies are not widely available. To improve treatment options, we conducted a high-throughput screen to uncover compounds that block SARS-CoV-2 infection. A minimally pathogenic human betacoronavirus (OC43) was used to infect physiologically-relevant human pulmonary fibroblasts (MRC5) to facilitate rapid antiviral discovery in a preclinical model. Comprehensive profiling was conducted on more than 600 compounds, with each compound arrayed across 10 dose points. Our screening revealed several FDA-approved agents that can attenuate both OC43 and SARS-CoV-2 viral replication, including lapatinib, doramapimod, and 17-AAG. Importantly, lapatinib inhibited SARS-CoV-2 RNA replication by over 50,000-fold. Further, both lapatinib and doramapimod could be combined with remdesivir to improve antiviral activity in cells. These findings reveal novel therapeutic avenues that could limit SARS-CoV-2 infection.


Subject(s)
Adenosine Monophosphate/analogs & derivatives , Alanine/analogs & derivatives , Antiviral Agents/pharmacology , COVID-19 Drug Treatment , Lapatinib/pharmacology , SARS-CoV-2/drug effects , Adenosine Monophosphate/pharmacology , Alanine/pharmacology , Animals , Benzoquinones/pharmacology , COVID-19/virology , Cell Line , Chlorocebus aethiops , Drug Combinations , Drug Discovery , Drug Synergism , High-Throughput Screening Assays , Humans , Lactams, Macrocyclic/pharmacology , Naphthalenes/pharmacology , Phenylurea Compounds/pharmacology , Pyrazoles/pharmacology , RNA, Viral/metabolism , Vero Cells , Virus Replication/drug effects
7.
Int J Nanomedicine ; 16: 5117-5131, 2021.
Article in English | MEDLINE | ID: covidwho-1362164

ABSTRACT

As a crucial organ, the lung is exposed to various harmful agents that may induce inflammation and oxidative stress, which may cause chronic or acute lung injury. Nigella sativa, also known as black seed, has been widely used to treat various diseases and is one of the most extensively researched medicinal plants. Thymoquinone (TQ) is the main component of black seed volatile oil and has been proven to have antioxidant, anti-inflammatory, and antineoplastic properties. The potential therapeutic properties of TQ against various pulmonary disorders have been studied in both in vitro and in vivo studies. Furthermore, the application of nanotechnology may increase drug solubility, cellular absorption, drug release (sustained or control), and drug delivery to lung tissue target sites. As a result, fabricating TQ as nanoparticles (NPs) is a potential therapeutic approach against a variety of lung diseases. In this current review, we summarize recent findings on the efficacy of TQ and its nanotypes in lung disorders caused by immunocompromised conditions such as cancer, diabetes, gastric ulcers, and other neurodegenerative diseases. It is concluded that TQ nanoparticles with anti-inflammatory, antioxidant, antiasthma, and antitumor activity may be safely applied to treat lung disorders. However, more research is required before TQ nanoparticles can be used as pharmaceutical preparations in human studies.


Subject(s)
Lung Injury , Nanoparticles , Benzoquinones , Humans , Nigella sativa
8.
Clin Exp Pharmacol Physiol ; 48(11): 1445-1453, 2021 11.
Article in English | MEDLINE | ID: covidwho-1322720

ABSTRACT

Nigella sativa (N. sativa) is an annual flowering plant that has been used as a traditional remedy for many centuries. The seed possesses a large variety of compounds with thymoquinone (TQ) considered its major but not sole bioactive constituent. Supercritical fluid extraction, geographical location, and oxidative status of N. sativa produces the highest yield of essential oil content including TQ. Thymoquinone is lipophilic, heat and light sensitive with low oral bioavailability and rapid elimination that have significantly inhibited its pharmacological development. Novel developments in nanoparticulate-based oral administration, nasal spray and transdermal delivery may allow the clinical development of N. sativa and TQ as therapeutic agents. Animal and human studies indicate a potential role of N. sativa seed oil and TQ for a diverse range of disease processes including hypertension, dyslipidaemia, type 2 diabetes mellitus, arthritis, asthma, bacterial and viral infections, neurological and dermatological disorders, as it belongs to the group of pan-assay interference compounds. This review outlines the pharmacological properties of N. sativa and TQ and their potential wide application for a large variety of human diseases. The paper will focus on recent studies of the anti-inflammatory and antiviral properties that make N. sativa and TQ promising therapeutic agents targeting contemporary inflammatory and infectious diseases including Covid 19.


Subject(s)
Benzoquinones/pharmacology , Communicable Diseases/drug therapy , Inflammation/drug therapy , Nigella sativa/chemistry , Animals , Benzoquinones/therapeutic use , Humans
9.
Vascul Pharmacol ; 141: 106899, 2021 12.
Article in English | MEDLINE | ID: covidwho-1322386

ABSTRACT

A new virus strain detected in late 2019 and not previously described in humans is the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes corona virus disease (COVID-19). While potential therapeutic approaches for COVID-19 are being investigated, significant initiatives are being made to create protective drugs and study various antiviral agents to cure the infection. However, an effective treatment strategy against COVID-19 is worrisome inadequate. The objective of the present manuscript is to discuss the potential role of thymoquinone (TQ) in preventing the cardiovascular complications of COVID-19, focusing on viral inhibition, antioxidant potential, vascular effect, and cardiac protection. The multifunctional properties of TQ could potentially synergize with the activity of current therapeutic interventions and offer a basis for managing COVID-19 disease more effectively. Even though the experimental evidence is positive, a translational application of TQ in COVID-19 is timely warranted.


Subject(s)
Benzoquinones/pharmacology , COVID-19/complications , Cardiovascular Diseases/prevention & control , Animals , Antiviral Agents/administration & dosage , Antiviral Agents/pharmacology , Benzoquinones/administration & dosage , Cardiotonic Agents/administration & dosage , Cardiotonic Agents/pharmacology , Cardiovascular Diseases/virology , Humans , SARS-CoV-2/isolation & purification , COVID-19 Drug Treatment
10.
Curr Pharm Biotechnol ; 22(10): 1315-1324, 2021.
Article in English | MEDLINE | ID: covidwho-1290817

ABSTRACT

BACKGROUND: Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is the causative agent of the current pandemic of Coronavirus Disease-2019 (COVID-19). The progression of COVID-19 is related to an excessive host inflammatory immune response to SARS-CoV-2 infection, which is considered a major cause of disease severity and death. Dysregulated immune response produces huge amounts of pro-inflammatory cytokines and chemokines called "cytokine storm". Moreover, the activation of microthrombi formation plays an important role in multiple organ failure. METHODS: Keeping into consideration the potent anti-inflammatory activity of black seed and its major constituent Thymoquinone (TQ), we hypothesize their potential implication in the treatment of COVID-19 patients. A literature search was performed in PubMed, ScienceDirect, Google Scholar and Scopus electronic databases using the terms, including black seed, N. sativa, thymoquinone, SARSCoV- 2, COVID-19 and inflammatory immune response. RESULTS: Various studies confirmed that Black seed and TQ reduced the thrombus formation, the expression of tissue factor and the immune activation. Furthermore, TQ demonstrated the broad-spectrum antimicrobial activity that may be effective in controlling the secondary infections in COVID-19 patients. CONCLUSION: Keeping into consideration the multi-targeting nature of the black seed and TQ, they may be used as a potential therapeutic formulation or as an adjunct therapy in the treatment of COVID-19 patients.


Subject(s)
COVID-19 , Benzoquinones , Cytokines , Humans , SARS-CoV-2 , Seeds
11.
Pharm Biol ; 59(1): 696-703, 2021 Dec.
Article in English | MEDLINE | ID: covidwho-1263613

ABSTRACT

CONTEXT: COVID-19 is a novel coronavirus that causes a severe infection in the respiratory system. Nigella sativa L. (Ranunculaceae) is an annual flowering plant used traditionally as a natural food supplement and multipurpose medicinal agent. OBJECTIVE: The possible beneficial effects of N. sativa, and its constituent, thymoquinone (TQ) on COVID-19 were reviewed. METHODS: The key words including, COVID-19, N. sativa, thymoquinone, antiviral effects, anti-inflammatory and immunomodulatory effects in different databases such as Web of Science (ISI), PubMed, Scopus, and Google Scholar were searched from 1990 up to February 2021. RESULTS: The current literature review showed that N. sativa and TQ reduced the level of pro-inflammatory mediators including, IL-2, IL-4, IL-6, and IL-12, while enhancing IFN-γ. Nigella sativa and TQ increased the serum levels of IgG1 and IgG2a, and improved pulmonary function tests in restrictive respiratory disorders. DISCUSSION AND CONCLUSIONS: These preliminary data of molecular docking, animal, and clinical studies propose N. sativa and TQ might have beneficial effects on the treatment or control of COVID-19 due to antiviral, anti-inflammatory and immunomodulatory properties as well as bronchodilatory effects. The efficacy of N. sativa and TQ on infected patients with COVID-19 in randomize clinical trials will be suggested.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Antiviral Agents/pharmacology , Benzoquinones/pharmacology , COVID-19 Drug Treatment , Nigella sativa , Plant Extracts/pharmacology , SARS-CoV-2/drug effects , Animals , Anti-Inflammatory Agents/isolation & purification , Antiviral Agents/isolation & purification , Benzoquinones/isolation & purification , COVID-19/immunology , COVID-19/metabolism , COVID-19/virology , Cytokines/metabolism , Humans , Immune System/drug effects , Immune System/immunology , Immune System/metabolism , Immune System/virology , Inflammation Mediators/metabolism , Lung/drug effects , Lung/immunology , Lung/metabolism , Lung/virology , Nigella sativa/chemistry , Plant Extracts/isolation & purification , SARS-CoV-2/immunology , SARS-CoV-2/pathogenicity
12.
Drug Des Devel Ther ; 15: 1819-1833, 2021.
Article in English | MEDLINE | ID: covidwho-1225832

ABSTRACT

COVID-19 has caused a major global health crisis, as excessive inflammation, oxidation, and exaggerated immune response in some sufferers can lead to a condition known as cytokine storm, which may progress to acute respiratory distress syndrome (ARDs), which can be fatal. So far, few effective drugs have emerged to assist in the treatment of patients with COVID-19, though some herbal medicine candidates may assist in the fight against COVID-19 deaths. Thymoquinone (TQ), the main active ingredient of black seed oil, possesses antioxidant, anti-inflammatory, antiviral, antimicrobial, immunomodulatory and anticoagulant activities. TQ also increases the activity and number of cytokine suppressors, lymphocytes, natural killer cells, and macrophages, and it has demonstrated antiviral potential against a number of viruses, including murine cytomegalovirus, Epstein-Barr virus, hepatitis C virus, human immunodeficiency virus, and other coronaviruses. Recently, TQ has demonstrated notable antiviral activity against a SARSCoV-2 strain isolated from Egyptian patients and, interestingly, molecular docking studies have also shown that TQ could potentially inhibit COVID-19 development through binding to the receptor-binding domain on the spike and envelope proteins of SARS-CoV-2, which may hinder virus entry into the host cell and inhibit its ion channel and pore forming activity. Other studies have shown that TQ may have an inhibitory effect on SARS CoV2 proteases, which could diminish viral replication, and it has also demonstrated good antagonism to angiotensin-converting enzyme 2 receptors, allowing it to interfere with virus uptake into the host cell. Several studies have also noted its potential protective capability against numerous chronic diseases and conditions, including diabetes, hypertension, dyslipidemia, asthma, renal dysfunction and malignancy. TQ has recently been tested in clinical trials for the treatment of several different diseases, and this review thus aims to highlight the potential therapeutic effects of TQ in the context of the COVID-19 pandemic.


Subject(s)
Benzoquinones/therapeutic use , COVID-19 Drug Treatment , SARS-CoV-2 , Anti-Inflammatory Agents/pharmacology , Antioxidants/pharmacology , Benzoquinones/pharmacology , COVID-19/prevention & control , Comorbidity , Epigenesis, Genetic , Humans , Molecular Docking Simulation , SARS-CoV-2/chemistry
13.
J Biomol Struct Dyn ; 40(18): 8274-8285, 2022 11.
Article in English | MEDLINE | ID: covidwho-1195663

ABSTRACT

Acetaminophen and N-acetyl cysteine (NAC) are being used as supportive care in patients suffering from coronavirus disease 2019 (COVID-19). The coagulopathy and cerebral hemorrhage have been recently reported in these patients. Prolonged acetaminophen use increases the international normalized ratio (INR) and the risk of bleeding among patients taking anti-coagulants. Inhibition of vitamin K epoxide reductase (VKOR) by acetaminophen and NAC in chronic applications has been reported, however, detailed knowledge of the molecular mechanism and binding sites are not clear. Herein, we built the homology model of human VKOR (hVKOR) using ITASSER server, confirmed, and applied it for docking analysis of its interaction with acetaminophen and its metabolite, N-acetyl-p-benzoquinone imine (NAPQI), and NAC. We also calculated the lipophilicity and predicted the blood-brain-barrier (BBB) permeation of NAPQI by Swiss ADME. Our analysis showed that NAPQI and NAC, but not acetaminophen, bind strongly to the similar sites in hVKOR via both hydrogen and van der Waals bonding; particularly with Cys135. Thus, it interrupted the vitamin K reducing electron transfer pathway. Further, molecular dynamic (MD) simulation study revealed that the interactions of the ligands with hVKOR are stable. In conclusion, our analysis shed a light on the molecular mechanism of acetaminophen-induced coagulopathy previously reported in some clinical cases with chronic acetaminophen use. Furthermore, considering the anti-coagulopathy of NAPQI and NAC but not acetaminophen, the BBB permeation potency of these agents, and the risk of coagulopathy in COVID-19, we suggest a regular prothrombin time (PT) and INR monitoring of these patients taking acetaminophen and/or NAC.Communicated by Ramaswamy H. Sarma.


Subject(s)
Acetaminophen , COVID-19 Drug Treatment , Acetaminophen/adverse effects , Acetaminophen/metabolism , Acetylcysteine , Benzoquinones/chemistry , Benzoquinones/metabolism , Humans , Hydrogen , Imines/chemistry , Vitamin K , Vitamin K Epoxide Reductases
14.
Cells ; 10(2)2021 02 02.
Article in English | MEDLINE | ID: covidwho-1060286

ABSTRACT

Since the beginning of the SARS-CoV-2(severe acute respiratory syndrome-coronavirus-2) pandemic, arace to develop a vaccine has been initiated, considering the massive and rather significant economic and healthcare hits that this virus has caused. The pathophysiology occurring following COVID-19(coronavirus disease-2019) infection has givenhints regarding the supportive and symptomatic treatments to establish for patients, as no specific anti-SARS-CoV-2 is available yet. Patient symptoms vary greatly and range from mild symptoms to severe fatal complications. Supportive treatments include antipyretics, antiviral therapies, different combinations of broad-spectrum antibiotics, hydroxychloroquine and plasma transfusion. Unfortunately, cancer patients are at higher risk of viral infection and more likely to develop serious complications due to their immunocompromised state, the fact that they are already administering multiple medications, as well as combined comorbidity compared to the general population. It may seem impossible to find a drug that possesses both potent antiviral and anticancer effects specifically against COVID-19 infection and its complications and the existing malignancy, respectively. Thymoquinone (TQ) is the most pharmacologically active ingredient in Nigella sativa seeds (black seeds); it is reported to have anticancer, anti-inflammatory and antioxidant effects in various settings. In this review, we will discuss the multiple effects of TQ specifically against COVID-19, its beneficial effects against COVID-19 pathophysiology and multiple-organ complications, its use as an adjuvant for supportive COVID-19 therapy and cancer therapy, and finally, its anticancer effects.


Subject(s)
Antineoplastic Agents , Antiviral Agents , Benzoquinones , COVID-19 Drug Treatment , COVID-19 , Drug Repositioning , Neoplasms , Animals , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Antiviral Agents/pharmacology , Antiviral Agents/therapeutic use , Benzoquinones/pharmacology , Benzoquinones/therapeutic use , COVID-19/complications , Cell Line, Tumor , Endoplasmic Reticulum Chaperone BiP , Humans , Mice , Neoplasms/complications , Neoplasms/drug therapy , Rats
15.
J Infect Public Health ; 13(12): 1868-1877, 2020 Dec.
Article in English | MEDLINE | ID: covidwho-1023648

ABSTRACT

BACKGROUND: Quinones are reactive to proteins containing cysteine residues and the main protease in Covid-19 contains an active site that includes Cys145. Embelin, a quinone natural product, is known to have antiviral activity against influenza and hepatitis B. Preliminary studies by our group also indicate its ability to inhibit HSV-1 in cultured cells. METHODS: Docking and DFT methods applied to the protease target. RESULTS: a mechanism for this inhibition of the SARS-CoV-2 Mpro protease is described, specifically due to formation of a covalent bond between S(Cys145) and an embelin C(carbonyl). This is assisted by two protein amino acids (1) N(imidazole-His41) which is able to capture H[S(Cys145)] and (2) HN(His163), which donates a proton to embelin O(carbonyl) forming an OH moiety that results in inhibition of the viral protease. A similar process is also seen with the anti-inflammatory drugs methyl prednisolone and dexamethasone, used for Covid-19 patients. Methyl prednisolone and dexamethasone are methide quinones, and possess only one carbonyl moiety, instead of two for embelin. Additional consideration was given to another natural product, emodin, recently patented against Covid-19, as well as some therapeutic quinones, vitamin K, suspected to be involved in Covid-19 action, and coenzyme Q10. All show structural similarities with embelin, dexamethasone and methyl prednisolone results. CONCLUSIONS: Our data on embelin and related quinones indicate that these natural compounds may represent a feasible, strategic tool against Covid-19.


Subject(s)
Anti-Inflammatory Agents/pharmacology , COVID-19 Drug Treatment , SARS-CoV-2/drug effects , Benzoquinones/pharmacology , Dexamethasone/pharmacology , Drug Repositioning , Humans , Methylprednisolone/pharmacology , Molecular Docking Simulation
16.
Emerg Microbes Infect ; 9(1): 2663-2672, 2020 Dec.
Article in English | MEDLINE | ID: covidwho-919316

ABSTRACT

Rapid accumulation of viral proteins in host cells render viruses highly dependent on cellular chaperones including heat shock protein 90 (Hsp90). Three highly pathogenic human coronaviruses, including MERS-CoV, SARS-CoV and SARS-CoV-2, have emerged in the past 2 decades. However, there is no approved antiviral agent against these coronaviruses. We inspected the role of Hsp90 for coronavirus propagation. First, an Hsp90 inhibitor, 17-AAG, significantly suppressed MERS-CoV propagation in cell lines and physiological-relevant human intestinal organoids. Second, siRNA depletion of Hsp90ß, but not Hsp90α, significantly restricted MERS-CoV replication and abolished virus spread. Third, Hsp90ß interaction with MERS-CoV nucleoprotein (NP) was revealed in a co-immunoprecipitation assay. Hsp90ß is required to maintain NP stability. Fourth, 17-AAG substantially inhibited the propagation of SARS-CoV and SARS-CoV-2. Collectively, Hsp90 is a host dependency factor for human coronavirus MERS-CoV, SARS-CoV and SARS-COV-2. Hsp90 inhibitors can be repurposed as a potent and broad-spectrum antiviral against human coronaviruses.


Subject(s)
Antiviral Agents/pharmacology , Benzoquinones/pharmacology , HSP90 Heat-Shock Proteins/antagonists & inhibitors , HSP90 Heat-Shock Proteins/genetics , Host Microbial Interactions/drug effects , Lactams, Macrocyclic/pharmacology , Middle East Respiratory Syndrome Coronavirus/drug effects , A549 Cells , Animals , Cell Line , Chlorocebus aethiops , HEK293 Cells , Humans , Intestines/virology , Organ Culture Techniques , RNA, Small Interfering , Severe acute respiratory syndrome-related coronavirus/drug effects , SARS-CoV-2/drug effects , Vero Cells , Virus Replication/drug effects , COVID-19 Drug Treatment
17.
Drug Res (Stuttg) ; 71(1): 4-9, 2021 Jan.
Article in English | MEDLINE | ID: covidwho-894439

ABSTRACT

Drug repositioning is a strategy that identifies new uses of approved drugs to treat conditions different from their original purpose. Current efforts to treat Covid-19 are based on this strategy. The first drugs used in patients infected with SARS-CoV-2 were antimalarial drugs. It is their mechanism of action, i. e., rise in endosomal pH, which recommends them against the new coronavirus. Disregarding their side effects, the study of their antiviral activity provides valuable hints for the choice and design of drugs against SARS-CoV-2. One prominent drug candidate is thymoquinone, an antimalarial substance contained in Nigella sativa - most likely one of the first antimalarial drugs in human history. Since the outbreak of the pandemic, the number of articles relating thymoquinone to Covid-19 continuously increases. Here, we use it as an exemplary model drug, compare its antiviral mechanism with that of conventional antimalarial drugs and establish an irreducible parametric scheme for the identification of drugs with a potential in Covid-19.Translation into the laboratory is simple. Starting with the discovery of Nigella sativa seeds in the tomb of Pharaoh Tutankhamun, we establish a physicochemical model for the interaction of thymoquinone with both coronavirus and cells. Exploiting the predictive capability of the model, we provide a generalizable scheme for the systematic choice and design of drugs for Covid-19. An unexpected offshoot of our research is that Tutankhamun could not have died of malaria, a finding contrary to the mainstream theory.


Subject(s)
Antimalarials/therapeutic use , COVID-19 Drug Treatment , Nigella sativa/chemistry , Antimalarials/history , Antiviral Agents/therapeutic use , Benzoquinones/pharmacology , Benzoquinones/therapeutic use , Drug Repositioning , Egypt , Famous Persons , History, Ancient , Humans
18.
Phytother Res ; 35(3): 1329-1344, 2021 Mar.
Article in English | MEDLINE | ID: covidwho-844376

ABSTRACT

Nigella sativa seed and its active compounds have been historically recognized as an effective herbal panacea that can establish a balanced inflammatory response by suppressing chronic inflammation and promoting healthy immune response. The essential oil and other preparations of N. sativa seed have substantial therapeutic outcomes against immune disturbance, autophagy dysfunction, oxidative stress, ischemia, inflammation, in several COVID-19 comorbidities such as diabetes, cardiovascular disorders, Kawasaki-like diseases, and many bacterial and viral infections. Compelling evidence in the therapeutic efficiency of N. sativa along with the recent computational findings is strongly suggestive of combating emerged COVID-19 pandemic. Also, being an available candidate in nutraceuticals, N. sativa seed oil could be immensely potential and feasible to prevent and cure COVID-19. This review was aimed at revisiting the pharmacological benefits of N. sativa seed and its active metabolites that may constitute a potential basis for developing a novel preventive and therapeutic strategy against COVID-19. Bioactive compounds of N. sativa seed, especially thymiquinone, α-hederin, and nigellidine, could be alternative and promising herbal drugs to combat COVID-19. Preclinical and clinical trials are required to delineate detailed mechanism of N. sativa's active components and to investigate their efficacy and potency under specific pathophysiological conditions of COVID-19.


Subject(s)
COVID-19 Drug Treatment , Nigella sativa/chemistry , Plant Extracts/pharmacology , Seeds/chemistry , Benzoquinones , Diabetes Mellitus/drug therapy , Dietary Supplements , Humans , Oleanolic Acid/analogs & derivatives , Pandemics , Saponins
19.
Biomed Res Int ; 2020: 1594726, 2020.
Article in English | MEDLINE | ID: covidwho-633800

ABSTRACT

Acute kidney injury (AKI) is a common complication of sepsis and has also been observed in some patients suffering from the new coronavirus pneumonia COVID-19, which is currently a major global concern. Thymoquinone (TQ) is one of the most active ingredients in Nigella sativa seeds. It has a variety of beneficial properties including anti-inflammatory and antioxidative activities. Here, we investigated the possible protective effects of TQ against kidney damage in septic BALB/c mice. Eight-week-old male BALB/c mice were divided into four groups: control, TQ, cecal ligation and puncture (CLP), and TQ+CLP. CLP was performed after 2 weeks of TQ gavage. After 48 h, we measured the histopathological alterations in the kidney tissue and the serum levels of creatinine (CRE) and blood urea nitrogen (BUN). We also evaluated pyroptosis (NLRP3, caspase-1), apoptosis (caspase-3, caspase-8), proinflammatory (TNF-α, IL-1ß, and IL-6)-related protein and gene expression levels. Our results demonstrated that TQ inhibited CLP-induced increased serum CRE and BUN levels. It also significantly inhibited the high levels of NLRP3, caspase-1, caspase-3, caspase-8, TNF-α, IL-1ß, and IL-6 induced by CLP. Furthermore, NF-κB protein level was significantly decreased in the TQ+CLP group than in the CLP group. Together, our results indicate that TQ may be a potential therapeutic agent for sepsis-induced AKI.


Subject(s)
Acute Kidney Injury/drug therapy , Acute Kidney Injury/etiology , Benzoquinones/therapeutic use , Sepsis/complications , Sepsis/drug therapy , Acute Kidney Injury/pathology , Animals , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Antioxidants/therapeutic use , Apoptosis/drug effects , Betacoronavirus , Blood Urea Nitrogen , COVID-19 , Coronavirus Infections/complications , Coronavirus Infections/drug therapy , Creatinine/blood , Cytokines/metabolism , Disease Models, Animal , Humans , Inflammation Mediators/metabolism , Kidney/drug effects , Kidney/metabolism , Kidney/pathology , Male , Mice , Mice, Inbred BALB C , NF-kappa B/metabolism , Pandemics , Pneumonia, Viral/complications , Pneumonia, Viral/drug therapy , SARS-CoV-2
20.
Phytomedicine ; 85: 153277, 2021 May.
Article in English | MEDLINE | ID: covidwho-643666

ABSTRACT

The world is witnessing a difficult time. The race of developing a new coronavirus (COVID-19) vaccine is becoming more urgent. Many preliminary studies on the pathophysiology of COVID-19 patients have provided some clues to treat this pandemic. However, no suitable treatment has found yet. Various symptoms of patients infected with COVID-19 indicated the importance of immune regulation in the human body. Severe cases admitted to the intensive care unit showed high level of pro-inflammatory cytokines which enhanced the disease severity. Acute Respiratory Distress Syndrome (ARDS) in COVID-19 patients is another critical factor of disease severity and mortality. So, Immune modulation is the only way of regulating immune system. Nigella sativa has been used for medicinal purposes for centuries. The components of this plant are known for its intense immune-regulatory, anti-inflammatory, and antioxidant benefits in obstructive respiratory disorders. A molecular docking study also gave evidences that N. sativa decelerates COVID-19 and might give the same or better results than the FDA approved drugs. The aim of this review was to investigate the possible immune-regulatory effects of N. sativa on COVID-19 pandemic. Our review found N. sativa's Thymoquinone, Nigellidine, and α-hederin can be a potential influencer in reinforcing the immune response on molecular grounds.


Subject(s)
COVID-19 Drug Treatment , Immune System/drug effects , Nigella sativa/chemistry , Plant Extracts/pharmacology , Animals , Anti-Inflammatory Agents/pharmacology , Antioxidants/pharmacology , Benzoquinones/pharmacology , Drug Evaluation, Preclinical , Humans , Molecular Docking Simulation , Oleanolic Acid/pharmacology , Pandemics , SARS-CoV-2/drug effects
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