Quercetin as an Antiviral Agent Inhibits Influenza A Virus (IAV) Entry

Exploring antiviral effect and mechanism of Jinye Baidu granules（JYBD）against influenza A virus through network pharmacology and in vitro and invivo experiments

ETHNOPHARMACOLOGICAL RELEVANCE

Jinye Baidu granules (JYBD) have been used to treat acute respiratory tract infections and demonstrated clinical efficacy for the treatment of emerging or epidemic respiratory viruses such as SARS-CoV-2 and influenza virus.

AIM OF THE STUDY

This study is to investigate the antiviral effect of JYBD against influenza A viruses (IAV) in vitro and in vivo and elucidate its underlying mechanism.

MATERIALS AND METHODS

Ultra-high-performance liquid chromatography connected with Orbitrap mass spectrometer (UHPLC-Orbitrap MS) was employed to describe the chemical profile of JYBD. The potential pathways and targets involved in JYBD against IAV infection were predicted by network pharmacology. The efficacy and mechanism of JYBD were validated through both in vivo and in vitro experiments. Moreover, combination therapy with JYBD and the classic anti-influenza drugs was also investigated.

RESULTS

A total of 126 compounds were identified by UHPLC-Orbitrap MS, of which 9 compounds were unambiguously confirmed with reference standards. JYBD could significantly inhibit the replication of multiple strains of IAV, especially oseltamivir-resistant strains. The results of qRT-PCR and WB demonstrated that JYBD could inhibit the excessive induction of pro-inflammatory cytokines induced by IAV infection and regulate inflammatory response through inhibiting JAK/STAT, NF-κB and MAPK pathways. Moreover, both JYBD monotherapy or in combination with oseltamivir could alleviate IAV-induced severe lung injury in mice.

CONCLUSIONS

JYBD could inhibit IAV replication and mitigate virus-induced excessive inflammatory response. Combinations of JYBD and neuraminidase inhibitors conferred synergistic suppression of IAV both in vitro and in vivo. It might provide a scientific basis for clinical applications of JYBD against influenza virus infected diseases.

Investigating the antiviral activity of Erigeron annuus (L.) pers extract against RSV and examining its active components

ETHNOPHARMACOLOGICAL RELEVANCE

The plants in the genus Erigeron are known to exhibit antiviral activities, including those against the respiratory syncytial virus (RSV). In traditional medicine Erigeron annuus (L.) Pers (EA) has been used in the treatment of pulmonary diseases and acute infectious hepatitis.

AIM OF THIS STUDY

The aim of this study is to determine the optimum extraction method to produce the most potent anti-RSV extract, elucidate its mode and mechanisms of antiviral activity in both in vitro and in vivo models, and identify the chemical structures of the bioactive compounds.

MATERIALS AND METHODS

The whole plant of EA was extracted with ethyl acetate, methanol, ethanol, water, aqueous methanol (60, 80% and 100%) and aqueous ethanol (50, 75% and 95%) using maceration, reflux, and ultrasound-assisted extraction methods. The antiviral activities of the extracts were determined in vitro. The in vitro antiviral activities of the extracts were determined using Hep-2 cells. Four in vitro experiments were performed to determine the mode of antiviral activity of the most active extract, ethyl acetate fraction (EAE) of Erigeron annuus whole plant extract prepared by refluxing with 50% ethanol, by examining its ability to inactivate the virus directly, inhibit viral adsorption and penetration, inhibit viral replication and preventive effect. The effect of temperature and duration of treatment on these modes of action was also determined. The antiviral activity of the EAE was also assessed in vivo in a mouse model. The lung index, viral load, and lung tissue histology were measured. qRT-PCR and ELISA studies were performed to determine the expression of key genes (TLR-3 and TLR-4) and proteins (IL-2, IFN-γ, and TNF-α) related to RSV infection. The most active antiviral compound was isolated using chromatography techniques, and its chemical structure was identified through electrospray triple quadrupole mass spectroscopy and nuclear magnetic resonance spectroscopy.

RESULTS

The EAE was the most active on RSV. In vitro experiments showed that the antiviral activity of EAE is via direct inactivation, inhibition of entry, and inhibition of the proliferation of the virus. In vivo experiments showed that the EAE effectively inhibited the proliferation of RSV in the lungs and alleviated the lung tissue lesions in RSV-infected mice. The antiviral activity of the EAE is mediated by downregulating the expression of TLR3 and TLR4 in the lung, upregulating the expression of IL-2 and IFN-γ, and downregulating the expression of TNF-α. Apigenin 7-O-methylglucuronide was found to be a major bioactive compound in EAE.

CONCLUSIONS

The results of this study confirmed the antiviral activity of EA by inactivating, inhibiting the entry, and inhibiting the proliferation of RSV. The activity is mediated by regulating the immunity and inflammatory mediators. Apigenin 7-O-methylglucuronide is the bioactive compound present in EA.

Quercetin, the Potential Powerful Flavonoid for Human and Food: A Review

Flavonoids occur naturally in different types of fruits and vegetables, including tea, cabbage, cauliflower, elderberries, cranberries, red apples, lettuce, pears, spinach, green hot peppers, white and red onions, kale, blueberries, and nuts. Among these flavonoids is quercetin, a potent natural antioxidant and cytotoxic substance with a number of therapeutic functions. Nowadays, quercetin is a common ingredient in many nutraceutical and cosmeceutical products due to its antioxidant properties. Its antibacterial effects and possible action mechanisms have been explored in many studies. From these, it has been established that quercetin stops the activity of numerous Gram-negative and -positive bacteria, fungi, and viruses. This review clarifies the plant sources and extraction methods of quercetin, as well as its medicinal applications as an antibacterial, antifungal, antiviral, and antioxidant agent, with a particular emphasis on the underlying mechanisms of its biological activity. The mechanism of its antimicrobial effect involves damaging the cell membrane-e.g., by changing its permeability, preventing biofilm formation, reducing the mitochondrial expression of virulence factors, and inhibiting protein and nucleic-acid synthesis. Moreover, quercetin has been shown to impede the activity of a variety of drug-resistant bacterial strains, pointing to the possibility of using it as a strong antimicrobial substance against such strains. In addition, it has occasionally been demonstrated that specific structural alterations to quercetin can increase its antibacterial action in comparison to the parent molecule. Overall, this review synthesizes our understanding of the mode of action of quercetin and its prospects for use as a therapeutic material.

Sangbaipi decoction exerted in vitro and in vivo anti-influenza effect through inhibiting viral proteins

HEADINGS ETHNOPHARMACOLOGICAL RELEVANCE

Sangbaipi Decoction (SBPD) is an effective treatment for lung diseases caused by phlegm-heat obstruction according to Jingyue Quanshu, and soothes panting by purging the lung meridian. It is composed of anti-pyretic herbs (e.g., Scutellaria baicalensis Georgi and Coptis chinensis Franch.) and antitussive herbs (e.g., Cortex Mori and Armeniacae Semen Amarum). Therefore, we hypothesized that SBPD has therapeutic effects on lung injury caused by influenza virus.

AIM OF THE STUDY

This study aimed to explore anti-influenza activity, active components, and mechanisms of SBPD.

MATERIALS AND METHODS

The anti-influenza activities of SBPD were determined in 48 h drug-treated MDCK cell model using CPE and plaque reduction assays, and 24 h drug-treated A549 cells using qRT-PCR. The in vivo efficacy of SBPD (1.0 g/kg/day and 0.5 g/kg/day) was evaluated in PR8 infected BALB/c mice. The chemical component was assessed through HPLC-Q-TOF MS/MS analysis. Network pharmacology was built via TCMSP, GeneCards, DisgeNet, OMIM, DrugBank databases, and Cytoscape software. Additionally, TOA, HI and NAI assays were employed to investigate impact on the virus replication cycle with different concentrations of SBPD (2.5 mg/mL, 1.25 mg/mL, or 0.625 mg/mL).

RESULTS

In MDCK infected with viruses A/PR/8/34, A/Hong Kong/1/68, or A/California/4/2009, the IC50 values of SBPD were 0.80 mg/mL, 1.20 mg/mL, and 1.25 mg/mL. In A549 cells, SBPD treatment reduced cytokine expression (e.g., TNF-α, IL-6, IL-1β) (p < 0.05). In PR8 infected BALB/c mice, SBPD improved the survival rate of infected mice, reduced lung index (p < 0.05), protected lung tissue from pathological damage, and regulated cytokine overexpression (p < 0.05). 29 components of SBPD were identified in SBPD treated mouse serum including some phytochemicals targeting influenza proteins. HI and NAI assays suggested the potential antiviral mechanism of SBPD through inhibition of HA and NA.

CONCLUSION

This study is the first to demonstrate the anti-influenza and the anti-inflammatory effects of SBPD in vitro and in vivo. Its major anti-influenza phytochemicals were explored and its inhibitory effects on HA and NA protein were proved. It provides more options for anti-influenza drug discovery.

Quercetin inhibited LPS-induced cytokine storm by interacting with the AKT1-FoxO1 and Keap1-Nrf2 signaling pathway in macrophages

Cytokine storm (CS) emerges as an exacerbated inflammatory response triggered by various factors such as pathogens and excessive immunotherapy, posing a significant threat to life if left unchecked. Quercetin, a monomer found in traditional Chinese medicine, exhibits notable anti-inflammatory and antiviral properties. This study endeavors to explore whether quercetin intervention could mitigate CS through a combination of network pharmacology analysis and experimental validation. First, common target genes and potential mechanisms affected by quercetin and CS were identified through network pharmacology, and molecular docking experiments confirmed quercetin and core targets. Subsequently, in vitro experiments of Raw264.7 cells stimulated by lipopolysaccharide (LPS) showed that quercetin could effectively inhibit the overexpression of pro-inflammatory mediators and regulate the AKT1-FoxO1 signaling pathway. At the same time, quercetin can reduce ROS through the Keap1-Nrf2 signaling pathway. In addition, in vivo studies of C57BL/6 mice injected with LPS further confirmed quercetin's inhibitory effect on CS. In conclusion, this investigation elucidated novel target genes and signaling pathways implicated in the therapeutic effects of quercetin on CS. Moreover, it provided compelling evidence supporting the efficacy of quercetin in reversing LPS-induced CS, primarily through the regulation of the AKT1-FoxO1 and Keap1-Nrf2 signaling pathways.

The interplay between cytokines, inflammation, and antioxidants: mechanistic insights and therapeutic potentials of various antioxidants and anti-cytokine compounds

Cytokines regulate immune responses essential for maintaining immune homeostasis, as deregulated cytokine signaling can lead to detrimental outcomes, including inflammatory disorders. The antioxidants emerge as promising therapeutic agents because they mitigate oxidative stress and modulate inflammatory pathways. Antioxidants can potentially ameliorate inflammation-related disorders by counteracting excessive cytokine-mediated inflammatory responses. A comprehensive understanding of cytokine-mediated inflammatory pathways and the interplay with antioxidants is paramount for developing natural therapeutic agents targeting inflammation-related disorders and helping to improve clinical outcomes and enhance the quality of life for patients. Among these antioxidants, curcumin, vitamin C, vitamin D, propolis, allicin, and cinnamaldehyde have garnered attention for their anti-inflammatory properties and potential therapeutic benefits. This review highlights the interrelationship between cytokines-mediated disorders in various diseases and therapeutic approaches involving antioxidants.

The therapeutic effect of Yinqiaosan decoction against influenza A virus infection by regulating T cell receptor signaling pathway

Background

Yinqiaosan decoction (YQSD), a traditional Chinese medicinal recipe, has been employed to treat influenza in China for approximately 300 years.

Objective

Our study aimed to explore the mechanisms of YQSD against influenza via in vivo and in vitro experimental studies.

Study design

and methods UHPLC-Q-TOF-MS/MS was utilized to examine the substances of the YQSD. The chemical components of YQSD detected by UHPLC-Q-TOF-MS/MS were used for network pharmacology analysis. The antiviral effect of YQSD in vivo was investigated. The potential mechanisms of YQSD in combating influenza, which were predicted from network pharmacology analysis, were validated in vitro.

Results

By use of UHPLC-Q-TOF-MS/MS, 97 compounds were identified from YQSD. Network pharmacology analysis revealed that the therapeutic effect of YQSD against influenza may be associated with the regulation of T cell receptors (TCR) and Phosphoinositide 3-Kinase (PI3K)- protein kinase B (Akt) signaling pathways. Treatment with YQSD significantly prolonged the mean survival time of the mice and reduced lung injury due to the influenza A virus in vivo. It was discovered that YQSD efficiently inhibited the expression of inflammation-related cytokines. Moreover, YQSD has been found to significantly reduce the expression levels of cluster of differentiation 3 (CD3), monocyte chemoattractant protein-1 (MCP-1), and H1N1 virus nucleoprotein (NP), and prevent the decrease of epithelial cadherin (E-cadherin) protein. In addition, YQSD can inhibit the phosphorylation of the zeta chain of T cell receptor-associated protein kinase 70 (ZAP70) and PI3K proteins in vitro.

Conclusion

The capacity of YQSD to suppress viral multiplication and inflammatory response by modulating T cell immunity may explain its effect against influenza viral pneumonia, which may involve the regulation of TCR and PI3K signaling pathways.

Baicalein analogues as prospective SARS-CoV-2 main protease (Mpro) inhibitors: A dataset of molecular docking-based virtual screening hits

The global coronavirus disease 2019 (COVID-19) pandemic originating from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has exerted profound damage to millions of lives. Baicalein is a flavonoid that has gotten a lot of attention as a possible SARS-CoV-2 main protease (Mpro) inhibitor because it can fight off many different viruses. We prepared and screened three sets of databases, each containing 2563 baicalein analogues, against Mpro using molecular docking simulation. The data showed that several baicalein analogues exhibited stable binding energies relative to standard baicalein, indicating that they have some selectivity against Mpro. The binding properties of the top three stable analogues from each database were further analyzed with respect to their binding properties, such as binding mode, binding energy, and binding interaction of putative stable ligand confirmations at the target binding site region.

Synthesis of new non-natural L-glycosidic flavonoid derivatives and their evaluation as inhibitors of Trypanosoma cruzi ecto-nucleoside triphosphate diphosphohydrolase 1 (TcNTPDase1)

Trypanosoma cruzi is the pathogen of Chagas disease, a neglected tropical disease that affects more than 6 million people worldwide. There are no vaccines to prevent infection, and the therapeutic arsenal is very minimal and toxic. The unique E-NTPDase of T. cruzi (TcNTPDase1) plays essential roles in adhesion and infection and is a virulence factor. Quercetin is a flavonoid with antimicrobial, antiviral, and antitumor activities. Its potential as a partial inhibitor of NTPDases has also been demonstrated. In this work, we synthesized the non-natural L-glycoside derivatives of quercetin and evaluated them as inhibitors of recombinant TcNTPDase1 (rTcNTPDase1). These compounds, and quercetin and miquelianin, a natural quercetin derivative, were also tested. Compound 16 showed the most significant inhibitory effect (94%). Quercetin, miquelianin, and compound 14 showed inhibition close to 50%. We thoroughly investigated the inhibitory effect of 16. Our data suggested a competitive inhibition with a Ki of 8.39 μM (± 0.90). To better understand the interaction of compound 16 and rTcNTPDase1, we performed molecular dynamics simulations of the enzyme and docking analyses with the compounds. Our predictions show that compound 16 binds to the enzyme's catalytic site and interacts with important residues for NTPDase activity. As an inhibitor of a critical T. cruzi enzyme, (16) could be helpful as a starting point in the developing of a future treatment for Chagas disease. Furthermore, the discovery of (16) as an inhibitor of TcNTPDase1 may open new avenues in the study and development of new inhibitors of E-NTPDases.

A small molecule compound targeting hemagglutinin inhibits influenza A virus and exhibits broad-spectrum antiviral activity

Influenza A virus (IAV) is a widespread pathogen that poses a significant threat to human health, causing pandemics with high mortality and pathogenicity. Given the emergence of increasingly drug-resistant strains of IAV, currently available antiviral drugs have been reported to be inadequate to meet clinical demands. Therefore, continuous exploration of safe, effective and broad-spectrum antiviral medications is urgently required. Here, we found that the small molecule compound J1 exhibited low toxicity both in vitro and in vivo. Moreover, J1 exhibits broad-spectrum antiviral activity against enveloped viruses, including IAV, respiratory syncytial virus (RSV), severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), human coronavirus OC43 (HCoV-OC43), herpes simplex virus type 1 (HSV-1) and HSV-2. In this study, we explored the inhibitory effects and mechanism of action of J1 on IAV in vivo and in vitro. The results showed that J1 inhibited infection by IAV strains, including H1N1, H7N9, H5N1 and H3N2, as well as by oseltamivir-resistant strains. Mechanistic studies have shown that J1 blocks IAV infection mainly through specific interactions with the influenza virus hemagglutinin HA2 subunit, thereby blocking membrane fusion. BALB/c mice were used to establish a model of acute lung injury (ALI) induced by IAV. Treatment with J1 increased survival rates and reduced viral titers, lung index and lung inflammatory damage in virus-infected mice. In conclusion, J1 possesses significant anti-IAV effects in vitro and in vivo, providing insights into the development of broad-spectrum antivirals against future pandemics.

Mechanisms underlying the therapeutic effects of Gang Huo Qing wen granules in the treatment of influenza based on network pharmacology, molecular docking and molecular dynamics

Influenza (Flu) is a severe health, medical, and economic problem, but no medication that has excellent outcomes and lowers the occurrence of these problems is now available. GanghuoQingwenGranules (GHQWG) is a common Chinese herbal formula for the treatment of influenza (flu). However, its methods of action remain unknown. We used network pharmacology, molecular docking, and molecular dynamics simulation techniques to investigate the pharmacological mechanism of GHQWG in flu. TCMSP and various types of literature were used to obtain active molecules and targets of GHQWG. Flu-related targets were found in the Online Mendelian Inheritance in Man (OMIM) database, the DisFeNET database, the Therapeutic Target Database (TTD), and the DrugBank database. To screen the key targets, a protein-protein interaction (PPI) network was constructed. DAVID was used to analyze GO and KEGG pathway enrichment. Target tissue and organ distribution was assessed. Molecular docking was used to evaluate interactions between possible targets and active molecules. For the ideal core protein-compound complexes obtained using molecular docking, a molecular dynamics simulation was performed. In total, 90 active molecules and 312 GHQWG targets were discovered. The PPI network's topology highlighted six key targets. GHQWG's effects are mediated via genes involved in inflammation, apoptosis, and oxidative stress, as well as the TNF and IL-17 signaling pathways, according to GO and KEGG pathway enrichment analysis. Molecular docking and molecular dynamics simulations demonstrated that the active compounds and tested targets had strong binding capabilities. This analysis accurately predicts the effective components, possible targets, and pathways involved in GHQWG flu treatment. We proposed a novel study strategy for future studies on the molecular processes of GHQWG in flu treatment. Furthermore, the possible active components provide a dependable source for flu drug screening.

Quercetin alleviates inflammation induced by porcine reproductive and respiratory syndrome virus in MARC-145 cells through the regulation of arachidonic acid and glutamine metabolism

BACKGROUND

Porcine reproductive and respiratory syndrome virus (PRRSV) infection causes severe inflammatory response, respiratory disease and sow reproductive failure. Quercetin is among the widely occurring polypheno found abundantly in nature. Quercetin has anti-inflammatory, anti-oxidative and anti-viral properties.

OBJECTIVES

This study aimed to explore the effect and mechanism of quercetin on PRRSV-induced inflammation in MARC-145 cells.

METHODS

Observing the cytopathic effect and measurements of inflammatory markers in MARC-145 cells collectively demonstrate that quercetin elicits a curative effect on PRRSV-induced inflammation. Liquid chromatography-mass spectrometry was further used for a non-targeted metabolic analysis of the role of quercetin in the metabolic regulation of PRRSV inflammation in MARC-145 cells.

RESULTS

It was shown that quercetin attenuated PRRSV-induced cytopathy in MARC-145 cells. Quercetin treatment inhibited PRRSV replication in MARC-145 cells in a dose-dependent manner. We also found that quercetin inhibited PRRSV-induced mRNA expression and secretion levels of tumour necrosis factor-α, interleukin 1β and interleukin 6. Metabolomics analysis revealed that quercetin ameliorated PRRSV-induced inflammation. Pathway analysis results revealed that PRRSV-induced pathways including arachidonic acid metabolism, linoleic acid, glycerophospholipid and alanine, aspartate and glutamate metabolism were suppressed by quercetin. Moreover, we confirmed that quercetin inhibited the activation of NF-κB/p65 pathway, probably by attenuating PLA2, ALOX and COX mRNA expression.

CONCLUSIONS

These results provide a crucial insight into the molecular mechanism of quercetin in alleviating PRRSV-induced inflammation.

Study on the mechanism of inhibition of Escherichia coli by Polygonum capitatum based on network pharmacology and molecular docking technology: A review

This study aims to analyze the effective components of Polygonum capitatum (PC) inhibiting Escherichia coli based on network pharmacology methods and predict its molecular mechanism of action. PC compounds and targets were collected from the TCMSP database, Swiss Target Prediction, and the literature. E coli targets were searched using the GeneCards database. The targets of E coli and the targets of the active ingredients of PC were taken as intersections to obtain the intersecting targets. The resulting overlapping targets were uploaded to the STRING database to construct the protein interaction network diagram of E coli target inhibition. The key targets for the inhibitory effect of PC on E coli were obtained. Gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses were performed by uploading key targets into the DAVID database. The results showed that there were 50 targets for PC to inhibit E coli. Among them, there are 5 core targets, mainly including AKT1, TNF, EGFR, JUN, and ESR1. A total of 196 gene ontology functional analysis results and 126 Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis results were obtained. These include cellular response to cadmium-ion, cellular response to reactive oxygen species, pathways in cancer, prostate cancer, and PI3K-Akt signaling pathway. Molecular docking results indicate that Lutedin, Hirsutin, Flazin, and Ellagic acid in PC have high affinity for the target genes AKT1, TNF, MAPK3 and EGFR. PC exerts its inhibitory effect on E coli through multi-targets and multi-pathways, which provides a new basis for the new use of PC as an old medicine.

Dietary Flavonoid Quercetin Supplement Promotes Antiviral Innate Responses Against Vesicular Stomatitis Virus Infection by Reshaping the Bacteriome and Host Metabolome in Mice

SCOPE

Active ingredients in functional foods exhibit broad-spectrum antiviral activity. The objective of this study is to investigate the protective effect of quercetin derived from bee propolis, a natural product with antiviral activity and modulating effects on the gut microbiota, against vesicular stomatitis virus (VSV) infection.

METHODS AND RESULTS

Through a cellular-based study, this study demonstrates that quercetin can modulate the activity of interferon-regulating factor 3 (IRF3). In vivo, it shows that quercetin protects mice from VSV infection by enhancing interferon production and inhibiting the production of proinflammatory cytokines. The study conducts 16S rRNA-based gut microbiota and nontargets metabolomics analyses to elucidate the mechanisms underlying quercetin-mediated bidirectional communication between the gut microbiome and host metabolome during viral infection. Quercetin not only ameliorates VSV-induced dysbiosis of the intestinal flora but also alters serum metabolites related to lipid metabolism. Cross-correlations between the gut bacteriome and the serum metabolome indicate that quercetin can modulate phosphatidylcholine (16:0/0:0) and 5-acetylamino-6-formylamino-3-methyluracil to prevent VSV infection.

CONCLUSION

This study systematically elucidates the anti-VSV mechanism of quercetin through gut bacteriome and host metabolome assays, offering new insights into VSV treatment and revealing the mechanisms behind a novel disease management strategy using dietary flavonoid supplements.

Hive Products: Composition, Pharmacological Properties, and Therapeutic Applications

Beekeeping provides products with nutraceutical and pharmaceutical characteristics. These products are characterized by abundance of bioactive compounds. For different reasons, honey, royal jelly, propolis, venom, and pollen are beneficial to humans and animals and could be used as therapeutics. The pharmacological action of these products is related to many of their constituents. The main bioactive components of honey include oligosaccharides, methylglyoxal, royal jelly proteins (MRJPs), and phenolics compounds. Royal jelly contains jelleins, royalisin peptides, MRJPs, and derivatives of hydroxy-decenoic acid, particularly 10-hydroxy-2-decenoic acid (10-HDA), which possess antibacterial, anti-inflammatory, immunomodulatory, neuromodulatory, metabolic syndrome-preventing, and anti-aging properties. Propolis has a plethora of activities that are referable to compounds such as caffeic acid phenethyl ester. Peptides found in bee venom include phospholipase A2, apamin, and melittin. In addition to being vitamin-rich, bee pollen also includes unsaturated fatty acids, sterols, and phenolics compounds that express antiatherosclerotic, antidiabetic, and anti-inflammatory properties. Therefore, the constituents of hive products are particular and different. All of these constituents have been investigated for their properties in numerous research studies. This review aims to provide a thorough screening of the bioactive chemicals found in honeybee products and their beneficial biological effects. The manuscript may provide impetus to the branch of unconventional medicine that goes by the name of apitherapy.

Pseudovirus-Based Systems for Screening Natural Antiviral Agents: A Comprehensive Review

Since the outbreak of COVID-19, researchers have been working tirelessly to discover effective ways to combat coronavirus infection. The use of computational drug repurposing methods and molecular docking has been instrumental in identifying compounds that have the potential to disrupt the binding between the spike glycoprotein of SARS-CoV-2 and human ACE2 (hACE2). Moreover, the pseudovirus approach has emerged as a robust technique for investigating the mechanism of virus attachment to cellular receptors and for screening targeted small molecule drugs. Pseudoviruses are viral particles containing envelope proteins, which mediate the virus's entry with the same efficiency as that of live viruses but lacking pathogenic genes. Therefore, they represent a safe alternative to screen potential drugs inhibiting viral entry, especially for highly pathogenic enveloped viruses. In this review, we have compiled a list of antiviral plant extracts and natural products that have been extensively studied against enveloped emerging and re-emerging viruses by pseudovirus technology. The review is organized into three parts: (1) construction of pseudoviruses based on different packaging systems and applications; (2) knowledge of emerging and re-emerging viruses; (3) natural products active against pseudovirus-mediated entry. One of the most crucial stages in the life cycle of a virus is its penetration into host cells. Therefore, the discovery of viral entry inhibitors represents a promising therapeutic option in fighting against emerging viruses.

The comparative analysis of Lonicerae Japonicae Flos and Lonicerae Flos: A systematical review

ETHNOPHARMACOLOGICAL RELEVANCE

Lonicerae Japonicae Flos (LJF) and Lonicerae Flos (LF) were once used as the same herb in China, but they were distinguished by Chinese Pharmacopoeia in 2005 in terms of their medicinal history, plant morphology, medicinal properties and chemical constituents. However, their functions, flavor, and meridian tropism are the same according to the Chinese pharmacopoeia 2020 edition, making researchers and customers confused.

AIM OF THE REVIEW

This review aimed to provide a comparative analysis of LJF and LF in order to provide a rational application in future research.

MATERIALS AND METHODS

The information was gathered from China National Knowledge Infrastructure (CNKI), SciFinder, Google Scholar, PubMed, Web of Science, and Chinese Masters and Doctoral Dissertations (all chosen articles were reviewed attentively from 1980.1 to 2023.8).

RESULTS

Till now, 507 chemical compounds have been isolated and identified in LJF, while 223 ones (79 overlapped compounds) are found in LF, including organic acids and derivatives, flavonoids, triterpenoids, iridoids, and essential oil components, etc. In addition, the pharmacological activities of LJF and LF, especially for their anti-influenza efficacy and mechanism, and their difference in terms of pharmacokinetic parameters, toxicology, and clinical applications were also summarized.

CONCLUSION

The current work offers comparative information between LJF and LF in terms of botany, traditional uses, phytochemistry, ethnopharmacology, pharmacokinetics, toxicology, and pharmacology, especially their anti-influenza activities. Despite the same clinical applications and similar chemical components in LJF and LF, differentiated components were still existed, resulting in differentiated pharmacological activities and pharmacokinetics parameters. Moreover, the research about anti-influenza mechanism and functional substances of LJF and LF is dramatically limited, restricting their clinical applications. In addition, few studies have investigated the metabolism feature of LF in vivo, which is one of the important bases for revealing the pharmacological mechanism of LF. At the same time, the toxicity of LJF and LF is not fully studied, and the toxic compounds of LJF and LF need to be screened out in order to standardize the drug use and improve their rational applications.

Flavonoids: A treasure house of prospective pharmacological potentials

Flavonoids are organic compounds characterized by a range of phenolic structures, which are abundantly present in various natural sources such as fruits, vegetables, cereals, bark, roots, stems, flowers, tea, and wine. The health advantages of these natural substances are renowned, and initiatives are being taken to extract the flavonoids. Apigenin, galangin, hesperetin, kaempferol, myricetin, naringenin, and quercetin are the seven most common compounds belonging to this class. A thorough analysis of bibliographic records from reliable sources including Google Scholar, Web of Science, PubMed, ScienceDirect, MEDLINE, and others was done to learn more about the biological activities of these flavonoids. These flavonoids appear to have promising anti-diabetic, anti-inflammatory, antibacterial, antioxidant, antiviral, cytotoxic, and lipid-lowering activities, according to evidence from in vitro, in vivo, and clinical research. The review contains recent trends, therapeutical interventions, and futuristic aspects of flavonoids to treat several diseases like diabetes, inflammation, bacterial and viral infections, cancers, and cardiovascular diseases. However, this manuscript should be handy in future drug discovery. Despite these encouraging findings, a notable gap exists in clinical research, hindering a comprehensive understanding of the effects of flavonoids at both high and low concentrations on human health. Future investigations should prioritize exploring bioavailability, given the potential for high inter-individual variation. As a starting point for further study on these flavonoids, this review paper may promote identifying and creating innovative therapeutic uses.

Inhibitory effects of kaempferol, quercetin and luteolin on the replication of human parainfluenza virus type 2 in vitro

The eight flavonoids, apigenin, chrysin, hesperidin, kaempferol, myricetin, quercetin, rutin and luteolin were tested for the inhibition of human parainfluenza virus type 2 (hPIV-2) replication. Three flavonoids out of the eight, kaempferol, quercetin and luteolin inhibited hPIV-2 replication. Kaempferol reduced the virus release (below 1/10,000), partly inhibited genome and mRNA syntheses, but protein synthesis was observed. It partly inhibited virus entry into the cells and virus spreading, and also partly disrupted microtubules and actin microfilaments, indicating that the virus release inhibition was partly caused by the disruption of cytoskeleton. Quercetine reduced the virus release (below 1/10,000), partly inhibited genome, mRNA and protein syntheses. It partly inhibited virus entry and spreading, and also partly destroyed microtubules and microfilaments. Luteolin reduced the virus release (below 1/100,000), largely inhibited genome, mRNA and protein syntheses. It inhibited virus entry and spreading. It disrupted microtubules and microfilaments. These results indicated that luteolin has the most inhibitory effect on hPIV-2 relication. In conclusion, the three flavonoids inhibited virus replication by the inhibition of genome, mRNA and protein syntheses, and in addition to those, by the disruption of cytoskeleton in vitro.

Quercetin Limits Tumor Immune Escape through PDK1/CD47 Axis in Melanoma

Quercetin (3,3[Formula: see text],4[Formula: see text],5,7-pentahydroxyflavone) is a bioactive plant-derived flavonoid, abundant in fruits and vegetables, that can effectively inhibit the growth of many types of tumors without toxicity. Nevertheless, the effect of quercetin on melanoma immunology has yet to be determined. This study aimed to investigate the role and mechanism of the antitumor immunity action of quercetin in melanoma through both in vivo and in vitro methods. Our research revealed that quercetin has the ability to boost antitumor immunity by modulating the tumor immune microenvironment through increasing the percentages of M1 macrophages, CD8[Formula: see text] T lymphocytes, and CD4[Formula: see text] T lymphocytes and promoting the secretion of IL-2 and IFN-[Formula: see text] from CD8[Formula: see text] T cells, consequently suppressing the growth of melanoma. Furthermore, we revealed that quercetin can inhibit cell proliferation and migration of B16 cells in a dose-dependent manner. In addition, down-regulating PDK1 can inhibit the mRNA and protein expression levels of CD47. In the rescue experiment, we overexpressed PDK1 and found that the protein and mRNA expression levels of CD47 increased correspondingly, while the addition of quercetin reversed this effect. Moreover, quercetin could stimulate the proliferation and enhance the function of CD8[Formula: see text] T cells. Therefore, our results identified a novel mechanism through which CD47 is regulated by quercetin to promote phagocytosis, and elucidated the regulation of quercetin on macrophages and CD8[Formula: see text] T cells in the tumor immune microenvironment. The use of quercetin as a therapeutic drug holds potential benefits for immunotherapy, enhancing the efficacy of existing treatments for melanoma.

Recommendations and guidelines of integrative medicine for COVID-19 care: The APEC project outcome

This article - Recommendations and Guidelines of Integrative Medicine (IM) for COVID-19 Care - was one of the outcomes from an Asia-Pacific Economic Cooperation (APEC) Project (Integrative Medicine (IM) and COVID -19 Care) during the time between May 2022 and March 2023. With the efforts from care providers, researchers, health policy makers and healthcare administrative leaders among APEC economies, the purpose of this file was to provide comprehensive IM systems for COVID-19 care as recommendations and suggestive guidelines including care methods, tools, procedures, symptom conditions and targets selections, and points need to be considered during care applications. All cited COVID-19 care practices have confirmed their efficacy and usefulness either used alone or combined with conventional medicine. This article provides current useful medical information on IM for COVID-19 care which could benefit APEC economies and world health communities on their healthcare system.

Quercetin may reduce the risk of developing the symptoms of COVID-19

Objective

Recent evidence reported that some dietary compounds like quercetin and apigenin as the most well-known flavonoids with anti-inflammatory effects may inhibit SARS-CoV-2 main protease. The hypothesis of the promising effects and possible mechanisms of action of quercetin against COVID-19 were assessed in this article.

Materials and Methods

Related papers on the inhibitory effects of quercetin against COVID-19 were collected using the following search strategy: "corona or coronavirus or COVID or COVID-19 or viral or virus" AND "nutrient or flavonoid or Quercetin".

Results

The findings indicated that quercetin can be considered an effective agent against COVID-19 because of its SARS-CoV-2 main protease and RNA-dependent RNA polymerase inhibitory effects. In addition, quercetin may attenuate angiotensin-converting enzyme-2 (ACE-2) receptors leading to a reduction of SARS-CoV-2 ability to enter host cells. Moreover, the antiviral, anti-inflammatory, and immunomodulatory activities of quercetin have been frequently reported.

Conclusion

Quercetin may be an effective agent for managing the complications of COVID-19. Further longitudinal human studies are warranted.

Polyphenol rich sugarcane extract (PRSE) has potential antiviral activity against influenza A virus in vitro

Influenza A virus (IAV) is one of the major global public health concerns but the emerging resistance of IAV to currently available antivirals requires the need to identify potential alternatives. Polyphenol rich sugarcane extract (PRSE) is an extract prepared from the sugarcane plant Saccharum Officinarum. Herein we aimed to determine if PRSE had antiviral activity against IAV. We showed that treatment of IAV-infected cells with PRSE results in a dose-dependent inhibition of virus infection at concentrations that were non-cytotoxic. PRSE treatment limited the early stages of infection, reducing viral genome replication, mRNA transcription and viral protein expression. PRSE did not affect the ability of IAV to bind sialic acid or change the morphology of viral particles. Additionally, PRSE treatment attenuated the replication of multiple IAV strains of the H3N2 and H1N1 subtype. In conclusion, we show that PRSE displays antiviral activity against a broad range of IAV strains, in vitro.

Clinical efficacy, pharmacodynamic components, and molecular mechanisms of antiviral granules in the treatment of influenza: A systematic review

ETHNOPHARMACOLOGICAL RELEVANCE

The Antiviral Granules (AG) are derived from the classical famous prescription, which is composed of 9 traditional Chinese medicines, namely Radix Isatidis (called Banlangen, BLG in Chinese), Forsythiae Fructus (called Lianqiao, LQ in Chinese), Gypsum fibrosum, Anemarrhenae Rhizoma (called Zhimu, ZM in Chinese), Phragmitis Rhizoma (called Lugen, LG in Chinese), Rehmanniae Radix (called Dihuang, DH in Chinese), Pogostemonis Herba (called Guanghuoxiang, GHX in Chinese), Acori Tatarinowii Rhizoma (called Shichangpu, SCP in Chinese), and Curcumae Radix (called Yujin, YJ in Chinese), and has shown an excellent therapeutic effect in clinical treatment of influenza. However, there are few studies on the anti-influenza mechanism of AG, and the mechanism of action is still unclear.

AIM OF THE STUDY

The purpose is to provide the latest information about the clinical efficacy, pharmacodynamic composition and mechanism of AG based on scientific literature, so as to enhance the utilization of AG in the treatment of influenza and related diseases, and promote the development and innovation of novel anti-influenza drugs targeting the influenza virus.

MATERIALS AND METHODS

Enter the data retrieval room, search for Antiviral Granules, as well as the scientific names, common names, and Chinese names of each Chinese medicine. Additionally, search for the relevant clinical applications, pharmacodynamic composition, pharmacological action, and molecular mechanism of both Antiviral Granules and single-ingredient medicines. Keywords includes terms such as "antiviral granules", "influenza", "Isatis indigotica Fort.", "Radix Isatidis", "Banlangeng", "pharmacology", "clinical application", "pharmacologic action", etc. and their combinations. Obtain results from the Web of Science, PubMed, Google Scholar, Sci Finder Scholar, CNKI and other resources.

RESULTS

AG is effective in the treatment of influenza and is often used in combination with other drugs to treat viral diseases. Its chemical composition is complex, including alkaloids, polysaccharides, volatile oils, steroid saponins, phenylpropanoids, terpenoids and other compounds. These compounds have a variety of pharmacological activities, which can interfere with the replication cycle of the influenza virus, regulate RIG-I-MAVS, JAK/STAT, TLRs/MyD88, NF-κB signaling pathways and related cytokines, regulate intestinal microorganisms, and protect both the lungs and extrapulmonary organs.

CONCLUSIONS

AG can overcome the limitations of traditional antiviral drug therapy, play a synergistic role in fighting influenza virus with the characteristics of multi-component, multi-pathway and multi-target therapy, and reverse the bodily function damage caused by influenza virus. AG may be a potential drug in the prevention and treatment of influenza and related diseases.

Recent Advances in Biologically Active Ingredients from Natural Drugs for Sepsis Treatment

Sepsis refers to the dysregulated host response to infection; its incidence and mortality rates are high. It is a worldwide medical problem but there is no specific drug for it. In recent years, clinical and experimental studies have found that many monomer components of traditional Chinese medicine have certain effects on the treatment of sepsis. This paper reviews the advances in research on the active ingredients of traditional Chinese medicine involved in the treatment of sepsis in recent years according to their chemical structure; it could provide ideas and references for further research and development in Chinese materia medica for the treatment of sepsis.

Inhibitory effects of quercetin on porcine epidemic diarrhea virus in vitro and in vivo

Porcine epidemic diarrhea (PED) is an acute, severe, highly contagious disease. Porcine epidemic diarrhea virus (PEDV) strains are prone to mutation, and the immune response induced by traditional vaccines may not be strong enough to be effective against the virus. Therefore, there is an urgent need to develop novel anti-PEDV drugs. This study aimed to explore the therapeutic effects of quercetin in PEDV infections in vitro (Vero cells) and in vivo (suckling piglets). Using transmission electron microscopy and laser confocal microscopy, we found that PEDV infection promotes the accumulation of lipid droplets (LDs). In vitro, studies showed that quercetin inhibits LD accumulation by down-regulating NF-κB signaling and IL-1β, IL-8, and IL-6 levels, thereby inhibiting viral replication. In vivo, studies in pigs demonstrated that quercetin can effectively relieve the clinical symptoms and intestinal injury caused by PEDV. Collectively, our findings suggest that quercetin inhibits PEDV replication both in vivo and in vitro, which provides a new direction for the development of PED antiviral drugs.

Evaluation of the Antiviral Activity of Tabamide A and Its Structural Derivatives against Influenza Virus

Influenza viruses cause severe endemic respiratory infections in both humans and animals worldwide. The emergence of drug-resistant viral strains requires the development of new influenza therapeutics. Tabamide A (TA0), a phenolic compound isolated from tobacco leaves, is known to have antiviral activity. We investigated whether synthetic TA0 and its derivatives exhibit anti-influenza virus activity. Analysis of structure-activity relationship revealed that two hydroxyl groups and a double bond between C7 and C8 in TA0 are crucial for maintaining its antiviral action. Among its derivatives, TA25 showed seven-fold higher activity than TA0. Administration of TA0 or TA25 effectively increased survival rate and reduced weight loss of virus-infected mice. TA25 appears to act early in the viral infection cycle by inhibiting viral mRNA synthesis on the template-negative strand. Thus, the anti-influenza virus activity of TA0 can be expanded by application of its synthetic derivatives, which may aid in the development of novel antiviral therapeutics.

In vitro antiviral effect of Mexican and Brazilian propolis and phenolic compounds against human coronavirus 229E

Propolis is a resinous substance collected by bees (Apis mellifera). It is used for its biological properties. This natural product is available as a safe therapeutic option. Herein, we report the antiviral effects of brown propolis extract from Mexico and green and red propolis extracts from Brazil, as well as their phenolic compounds (quercetin, caffeic acid, and rutin) in preventing infection of MRC-5 cells by HCoV-229E. Normal human fibroblast lung cells (MRC-5) were used to determine the cytotoxicity of the compounds. All samples studied showed antiviral activity. Green and brown propolis extracts, and quercetin exhibited the best EC50 values with values of 19.080, 11.240, and 77.208 µg/mL against HCoV-229E, respectively, and with TC50 of 62.19, 29.192, and 298 µg/mL on MRC-5 cells, respectively. These results are the first in vitro study of the effects of propolis on HCoV-229E and provide the basis for the development of natural formulations against other coronavirus strains.

Influenza virus cell entry and targeted antiviral development

Influenza virus infection is currently one of the most prevalent and transmissible diseases in the world causing local outbreaks every year. It has the potential to cause devastating global pandemics as well. The development of anti-influenza drugs possessing novel mechanisms of action is urgently needed to control the spread of influenza infections; thus, drugs that inhibit influenza virus entry into target cells are emerging as a hot research topic. In addition to discussing the biological significance of hemagglutinin in viral replication, this article provides recent updates on the natural products, small molecules, proteins, peptides, and neutralizing antibody-like proteins that have anti-influenza potency.

Comprehensive in silico screening of flavonoids against SARS-CoV-2 main protease

In the current pandemic caused by the new coronavirus (SARS-CoV-2), computational drug discovery can play an essential role in finding potential therapeutic agents. Thanks to its anti-viral, antibacterial, and anti-inflammatory properties, sage (Salvia officinalis) is used in traditional medicine. In this study, drugs proposed against COVID-19, including Lopinavir, Remdesivir, Favipiravir, and main flavonoids of sage, were docked favorably against novel coronavirus main protease. Molecular docking findings indicate that Rutin, Luteolin-7-glucoside, Apigenin, and Hispidulin make strong interactions with better binding affinity than selected commercial drugs in the study. But Rutin is the only flavonoid that makes strong hydrogen bond interactions with catalytic dyad and crucial Mpro residues and has more binding affinity than protease inhibitor PF-07321332 as an oral antiviral (PAXLOVID™). Further analysis of Molecular Dynamics and MM-PBSA predicted that chosen ligands could form stable complexes with the main protease. Also, ADMET analysis shows that main flavonoids are expected to have appropriate pharmacokinetic and no toxic properties. The results of the in silico study suggest that Salvia officinalis as a rich source of potent anti-coronavirus flavonoids may play a significant role in counteracting the replication of SARS-CoV-2.Communicated by Ramaswamy H. Sarma.

Peculiarities of clinical signs, course and treatment of musculoskeletal system lesions in post-COVID syndrome

Introduction

Post-COVID syndrome (PCS) is a frequent phenomenon of patients who have suffered from an acute attack of COVID-19 infection, and it is characterized by a wide range of symptoms from different organs and systems including the musculoskeletal system (MSS). However, peculiarities of MSS lesions have not been sufficiently studied to date, in particular, in the aspect of the therapeutic process. We aimed to investigate peculiarities of MSS lesions in patients with PCS.

Material and methods

Observations were carried out in 142 patients with PCS and MSS lesions. The age of patients was 36-67 years. Up-to-date methods of disease verification were used. An acute period of COVID-19 in all the patients was of moderate severity without oxygen support.

Results

Musculoskeletal system lesions in patients with PCS were found to appear 1-4 weeks after the experienced acute period of COVID-19 infection. Against the background of significant arthralgia (100%) in 93 (65.5%) patients manifestations of acute arthritis were detected, the frequency of which increased with age. Musculoskeletal system lesions were found against the background of dominating PCS manifestations from the cardiovascular and digestive systems. Deterioration of the course and results of treatment of diseases caused by an age-related polymorbid background was determined. Certain difficulties in the treatment of MSS lesions by means of non-steroidal anti-inflammatory drugs and limitation in the use of glucocorticosteroids are caused by severe gastroduodenopathy and arterial hypertension. Long-term, up to 6 months, administration of L-arginine, L-carnitine and quercetin in the rehabilitation complex improved the overall results of treatment of PCS manifestations including arthropathy.

Conclusions

Musculoskeletal system lesions in patients with PCS are not the main constituent of this syndrome. Difficulties in the treatment of arthropathy are due to the signs of gastroduodenopathy and arterial hypertension. Additional administration of L-arginine, L-carnitine and quercetin is reasonable.

Antiviral activity of zinc against hepatitis viruses: current status and future prospects

Viral hepatitis is a major public health concern globally. World health organization aims at eliminating viral hepatitis as a public health threat by 2030. Among the hepatitis causing viruses, hepatitis B and C are primarily transmitted via contaminated blood. Hepatitis A and E, which gets transmitted primarily via the feco-oral route, are the leading cause of acute viral hepatitis. Although vaccines are available against some of these viruses, new cases continue to be reported. There is an urgent need to devise a potent yet economical antiviral strategy against the hepatitis-causing viruses (denoted as hepatitis viruses) for achieving global elimination of viral hepatitis. Although zinc was known to mankind for a long time (since before Christ era), it was identified as an element in 1746 and its importance for human health was discovered in 1963 by the pioneering work of Dr. Ananda S. Prasad. A series of follow up studies involving zinc supplementation as a therapy demonstrated zinc as an essential element for humans, leading to establishment of a recommended dietary allowance (RDA) of 15 milligram zinc [United States RDA for zinc]. Being an essential component of many cellular enzymes and transcription factors, zinc is vital for growth and homeostasis of most living organisms, including human. Importantly, several studies indicate potent antiviral activity of zinc. Multiple studies have demonstrated antiviral activity of zinc against viruses that cause hepatitis. This article provides a comprehensive overview of the findings on antiviral activity of zinc against hepatitis viruses, discusses the mechanisms underlying the antiviral properties of zinc and summarizes the prospects of harnessing the therapeutic benefit of zinc supplementation therapy in reducing the disease burden due to viral hepatitis.

Computational approaches for innovative anti-viral drug discovery using Orthosiphon aristatus blume miq against dengue virus

Dengue virus has emerged as infectious mosquito borne disease involved in lowering platelets and white blood cells (WBC) count particularly. The genome structure is based on several structural and non-structural proteins essential for viral replication and progeny. One of the major proteins of replication is non-structural protein 3 (NS3) that transforms polyproteins into functional proteins with a cofactor non-structural protein (NS2B). Heat Shock Protein 70 (HSP70), is a human protein that assists in replication, viral entry and virion synthesis. Therefore, to inhibit the spread of dengue infection, there is a need of antivirals targeting replication proteins and other human proteins that help in dengue virus multiplication. By systemic approach based on molecular docking, ADMET (absorption, distribution, metabolism, excretion and toxicity) properties and molecular dynamic simulation (MD), potent inhibitors can be predicted. Inhibition of NS2B/NS3 dengue and HSP70 proteins involved in multiple steps in dengue virus progression can be prevented by using different phytochemicals. Molecular docking was performed using AutoDock Vina, PatchDock, and SwissDock. Interactions of obtained complex were observed in PyMOL and PLIP. Validation was checked by PROCHEK, simulation was performed using iMODS followed by preclinical testing by admetSAR. Ladanein, a flavonoid of Orthosiphon aristatus, was obtained as the lead compound to inhibit major replication protein of dengue virus with inhibitory potential against HSP70 protein. In summary, various in silico approaches were used to obtain the best phytochemical having anti-dengue potential.Communicated by Ramaswamy H. Sarma.

Rowanberry-A Source of Bioactive Compounds and Their Biopharmaceutical Properties

After a period of intense development in the synthesis pharmaceutical industry, plants are making a comeback in the public focus as remedies or therapeutic adjuvants and in disease prevention and ensuring the wellbeing and equilibrium of the human body. Plants are being recommended more and more in alimentation, in their natural form, or as extracts, supplements or functional aliments. People, in general, are in search of new sources of nutrients and phytochemicals. As a result, scientific research turns to lesser known and used plants, among them being rowanberries, a species of fruit very rich in nutrients and underused due to their bitter astringent taste and a lack of knowledge regarding the beneficial effects of these fruit. Rowan fruits (rowanberries) are a rich source of vitamins, polysaccharides, organic acids and minerals. They are also a source of natural polyphenols, which are often correlated with the prevention and treatment of modern world diseases. This article presents the existing data regarding the chemical composition, active principles and biopharmaceutical properties of rowan fruits and the different opportunities for their usage.

Arq Ajīb - a wonder Unani formulation for inhibiting SARS-CoV-2 spike glycoprotein and main protease - an in silico approach

OBJECTIVES

The current pandemic caused by Severe Acute Respiratory Syndrome Corona-Virus 2 (SARS-CoV-2) has become a global health menace with significant morbidity and mortality besides huge socioeconomic implications. Despite the approval of few vaccines for the prevention of the disease, the discovery of safe and effective countermeasures especially from natural sources is of paramount importance, as the number of cases continues escalating. Arq Ajīb has long been used for various diseases and its ingredients have been reported for antiviral, antimicrobial, antipyretic, anti-inflammatory, antioxidant activities. The present study investigates the inhibitory effect of phytocompound of Arq Ajīb on potential drug targets of SARS-CoV-2.

METHODS

The structures of phytocompounds present in Arq Ajīb were retrieved from PubChem database and some were illustrated using Marvin Sketch. SARS-CoV-2 S glycoprotein (PDB ID: 6LZG) and 3CLpro (PDB ID: 7BQY) were selected as the target protein. Dock Prep module in UCSF Chimera software was used for receptor structure processing. AutoDock Vina was used to calculate the binding affinities between the protein and ligands and to predict most promising compounds with best scores.

RESULTS

Molecular docking results predicted that the phytocompounds of Arq Ajīb had good binding affinity and interaction with S glycoprotein and 3CLpro. Quercetin and Isorhoifolin from Mentha arvensis were identified as promising candidates with the potential to interact with 3CLpro and spike glycoprotein and inhibit the viral replication and its entry into the host.

CONCLUSIONS

Arq Ajīb may prove valuable for developing novel therapeutic candidate for COVID-19; however, it has to be substantiated further with in-vitro and in-vivo studies.

Heat-Denatured Lysozyme is a Novel Potential Non-alcoholic Disinfectant Against Respiratory Virus

Respiratory diseases are significant recurrent threats to global public health. Since the 1918 Spanish flu pandemic, seasonal influenza viruses continue to cause epidemics around the world each year. More recently, the COVID-19 global pandemic conducted a public health crisis with more than 6 million deaths and it also severely affected the global economy. Due to the phenomenon that people get infection from objects carrying viruses, it has aroused people's attention to home disinfection. As there is no ideal existing common domestic disinfectant, new and safer antiviral disinfectants are urgently needed. Lysozyme is a natural antibacterial agent widespread in nature and widely used in healthcare and food industry because of is recognized safety. Recently, it has been shown that thermally denatured lysozyme has the ability to kill murine norovirus and hepatitis A virus. In our study, we also demonstrated that heat-denatured lysozyme (HDLz) had an antiviral effect against H1N1 influenza A virus, and we optimized its antiviral activities by testing different heating denaturation conditions, to generalize this property, using pseudotype virus neutralization assay, we found that HDLz can also inhibit the entry of H5N1, H5N6, and H7N1 avian influenza viruses as well as SARS-CoV and SARS-CoV-2 particles in cell with IC50 at the ng/mL range. Finally, using western blot analysis, we provide evidence that HDLz polymerization correlates with antiviral effect, which may be a precious possible quality control test. Altogether, our data support HDLz as a powerful anti-respiratory virus disinfectant as a sole or additive of current disinfectants to reduce concentration of toxic component.

Antiviral foods in the battle against viral infections: Understanding the molecular mechanism

Viruses produce a variety of illnesses, which may also cause acute respiratory syndrome. All viral infections, including COVID-19, are associated with the strength of the immune system. Till now, traditional medicine or vaccines for most viral diseases have not been effective. Antiviral and immune-boosting diets may provide defense against viral diseases by lowering the risk of infection and assisting rapid recovery. The purpose of this review was to gather, analyze, and present data based on scientific evidence in order to provide an overview of the mechanistic insights of antiviral bioactive metabolites. We have covered a wide range of food with antiviral properties in this review, along with their potential mechanism of action against viral infections. Additionally, the opportunities and challenges of using antiviral food have been critically reviewed. Bioactive plant compounds, not only help in maintaining the body's normal physiological mechanism and good health but are also essential for improving the body's immunity and therefore can be effective against viral diseases. These agents fight viral diseases either by incorporating the body's defense mechanism or by enhancing the cell's immune system. Regular intake of antiviral foods may prevent future pandemic and consumption of these antiviral agents with traditional medicine may reduce the severity of viral diseases. Therefore, the synergistic effect of antiviral foods and medication needs to be investigated.

Research Progress of Immunomodulation on Anti-COVID-19 and the Effective Components from Traditional Chinese Medicine

SARS-CoV-2 has posed a threat to the health of people around the world because of its strong transmission and high virulence. Currently, there is no specific medicine for the treatment of COVID-19. However, for a wide variety of medicines used to treat COVID-19, traditional Chinese medicine (TCM) plays a major role. In this paper, the effective treatment of COVID-19 using TCM was consulted first, and several Chinese medicines that were frequently used apart from their huge role in treating it were found. Then, when exploring the active ingredients of these herbs, it was discovered that most of them contained flavonoids. Therefore, the structure and function of the potential active substances of flavonoids, including flavonols, flavonoids, and flavanes, respectively, are discussed in this paper. According to the screening data, these flavonoids can bind to the key proteins of SARS-CoV-2, 3CLpro, PLpro, and RdRp, respectively, or block the interface between the viral spike protein and ACE2 receptor, which could inhibit the proliferation of coronavirus and prevent the virus from entering human cells. Besides, the effects of flavonoids on the human body systems are expounded on in this paper, including the respiratory system, digestive system, and immune system, respectively. Normally, flavonoids boost the body's immune system. However, they can suppress the immune system when over immunized. Ultimately, this study hopes to provide a reference for the clinical drug treatment of COVID-19 patients, and more TCM can be put into the market accordingly, which is expected to promote the development of TCM on the international stage.

Recent Advances in Potential Health Benefits of Quercetin

Quercetin, a flavonoid found in fruits and vegetables, has been a part of human diets for centuries. Its numerous health benefits, including antioxidant, antimicrobial, anti-inflammatory, antiviral, and anticancer properties, have been extensively studied. Its strong antioxidant properties enable it to scavenge free radicals, reduce oxidative stress, and protect against cellular damage. Quercetin's anti-inflammatory properties involve inhibiting the production of inflammatory cytokines and enzymes, making it a potential therapeutic agent for various inflammatory conditions. It also exhibits anticancer effects by inhibiting cancer cell proliferation and inducing apoptosis. Finally, quercetin has cardiovascular benefits such as lowering blood pressure, reducing cholesterol levels, and improving endothelial function, making it a promising candidate for preventing and treating cardiovascular diseases. This review provides an overview of the chemical structure, biological activities, and bioavailability of quercetin, as well as the different delivery systems available for quercetin. Incorporating quercetin-rich foods into the diet or taking quercetin supplements may be beneficial for maintaining good health and preventing chronic diseases. As research progresses, the future perspectives of quercetin appear promising, with potential applications in nutraceuticals, pharmaceuticals, and functional foods to promote overall well-being and disease prevention. However, further studies are needed to elucidate its mechanisms of action, optimize its bioavailability, and assess its long-term safety for widespread utilization.

NASAFYTOL® supplementation in adults hospitalized with COVID-19 infection: results from an exploratory open-label randomized controlled trial

Objectives

The effect and safety of Nasafytol^®, a food supplement combining curcumin, quercetin, and Vitamin D, on hospitalized COVID-19-positive patients as support to standard of care were to be assessed.

Methods

This exploratory, open-label, randomized, controlled trial was carried out among hospitalized adults with COVID-19 infection. Participants were randomly assigned to receive Nasafytol^® or Fultium^® control. The improvement of the clinical condition and occurrence of (serious) adverse events were evaluated. The study was registered on clincaltrials.gov with the identifier NCT04844658.

Results

Twenty-five patients received Nasafytol^®, and 24 received Fultium^®. Demographic characteristics were well balanced between the groups. On day 14 (or at hospital leave if < 14 days), no difference was observed between groups regarding their clinical condition, fever, or the need of oxygen therapy. At day 7, however, 19 participants had been discharged from the hospital in the Nasafytol^® arm compared to 10 participants in the Fultium^® arm. No participants were transferred to the ICU or died in the Nasafytol^® arm, vs. 4 transfers and 1 death in the Fultium^® arm. The clinical condition of participants in the Nasafytol^® arm had improved, as evidenced by a decrease in the COVID-19 WHO score. Interestingly, five SAEs occurred with Fultium^®, while no SAE was observed with Nasafytol^®.

Conclusion

Supplementation with Nasafytol^®, in addition to standard-of-care treatment, led to a faster discharge from the hospital, improved clinical conditions of participants, and a reduced risk of serious outcomes, including transfer to the intensive care unit or death, in patients hospitalized with COVID-19.

Protective role of flavonoids quercetin and silymarin in the viral-associated inflammatory bowel disease: an updated review

Inflammatory bowel disease (IBD) is a chronic recurrent inflammation of the gastrointestinal tract (GIT). IBD patients are susceptible to various infections such as viral infections due to the long-term consumption of immunosuppressive drugs and biologics. The antiviral and IBD protective traits of flavonoids have not been entirely investigated. This study objective included an overview of the protective role of flavonoids quercetin and silymarin in viral-associated IBD. Several viral agents such as cytomegalovirus (CMV), Epstein-Barr virus (EBV), varicella zoster virus (VZV) and enteric viruses can be reactivated and thus develop or exacerbate the IBD conditions or eventually facilitate the disease remission. Flavonoids such as quercetin and silymarin are non-toxic and safe bioactive compounds with remarkable anti-oxidant, anti-inflammatory and anti-viral effects. Mechanisms of anti-inflammatory and antiviral effects of silymarin and quercetin mainly include immune modulation and inhibition of caspase enzymes, viral binding and replication, RNA synthesis, viral proteases and viral assembly. In the nutraceutical sector, natural flavonoids low bioavailability and solubility necessitate the application of delivery systems to enhance their efficacy. This review study provided an updated understanding of the protective role of quercetin and silymarin against viral-associated IBD.

Integrating metabolomics and network pharmacology to assess the effects of quercetin on lung inflammatory injury induced by human respiratory syncytial virus

Quercetin (QR) has significant anti-respiratory syncytial virus (RSV) effects. However, its therapeutic mechanism has not been thoroughly explored. In this study, a lung inflammatory injury model caused by RSV was established in mice. Untargeted lung tissue metabolomics was used to identify differential metabolites and metabolic pathways. Network pharmacology was used to predict potential therapeutic targets of QR and analyze biological functions and pathways modulated by QR. By overlapping the results of the metabolomics and the network pharmacology analyses, the common targets of QR that were likely to be involved in the amelioration of RSV-induced lung inflammatory injury by QR were identified. Metabolomics analysis identified 52 differential metabolites and 244 corresponding targets, while network pharmacology analysis identified 126 potential targets of QR. By intersecting these 244 targets with the 126 targets, hypoxanthine-guanine phosphoribosyltransferase (HPRT1), thymidine phosphorylase (TYMP), lactoperoxidase (LPO), myeloperoxidase (MPO), and cytochrome P450 19A1 (CYP19A1) were identified as the common targets. The key targets, HPRT1, TYMP, LPO, and MPO, were components of purine metabolic pathways. The present study demonstrated that QR effectively ameliorated RSV-induced lung inflammatory injury in the established mouse model. Combining metabolomics and network pharmacology showed that the anti-RSV effect of QR was closely associated with purine metabolism pathways.

Repositioned Natural Compounds and Nanoformulations: A Promising Combination to Counteract Cell Damage and Inflammation in Respiratory Viral Infections

Respiratory viral diseases are among the most important causes of disability, morbidity, and death worldwide. Due to the limited efficacy or side effects of many current therapies and the increase in antiviral-resistant viral strains, the need to find new compounds to counteract these infections is growing. Since the development of new drugs is a time-consuming and expensive process, numerous studies have focused on the reuse of commercially available compounds, such as natural molecules with therapeutic properties. This phenomenon is generally called drug repurposing or repositioning and represents a valid emerging strategy in the drug discovery field. Unfortunately, the use of natural compounds in therapy has some limitations, due to their poor kinetic performance and consequently reduced therapeutic effect. The advent of nanotechnology in biomedicine has allowed this limitation to be overcome, showing that natural compounds in nanoform may represent a promising strategy against respiratory viral infections. In this narrative review, the beneficial effects of some promising natural molecules, curcumin, resveratrol, quercetin, and vitamin C, which have been already studied both in native form and in nanoform, against respiratory viral infections are presented and discussed. The review focuses on the ability of these natural compounds, analyzed in in vitro and in vivo studies, to counteract inflammation and cellular damage induced by viral infection and provide scientific evidence of the benefits of nanoformulations in increasing the therapeutic potential of these molecules.

Network pharmacology and bioinformatics to identify molecular mechanisms and therapeutic targets of Ruyi Jinhuang Powder in the treatment of monkeypox

Monkeypox outbreaks across the globe has aroused widespread concern. Ruyi Jinhuang Powder (RJP), a common formula in Chinese medicine, is used to treat pox-like illnesses. This study aimed to identify the molecular mechanisms and therapeutic targets of RJP for the treatment of monkeypox using network pharmacology and bioinformatics techniques. The bioactive substances and potential targets of each component of RJP were retrieved from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP). The differentially expressed genes (DEGs) of the monkeypox virus (MPXV) were identified from the GSE24125 by GEO2R. Key signaling pathways, bioactive components, and potential targets were obtained by bioinformatics analysis, including gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG), disease ontology (DO), and protein-protein interactions (PPI) analyses. Finally, molecular docking was used to predict the interaction between active compounds and core targets. A total of 158 active ingredients and 17 drug-disease-shared targets of RJP were screened. Bioinformatics indicated that wogonin and quercetin might be potential drug candidates. Potential therapeutic targets were identified. Immune-related mechanisms that exerted antiviral effects included signaling pathways like TNF, age-rage, and c-type lectin receptor pathways. Our results illustrated the good therapeutic effect of RJP on monkeypox in terms of biological activity, potential targets, and molecular mechanism. This also offered a promising strategy to reveal the scientific basis and therapeutic mechanism of herbal formulas used to treat the disease.

Impact of Senolytic Treatment on Gene Expression in Aged Lung

Cellular senescence plays a key role in mediating tissue remodeling and modulation of host responses to pathogenic stimuli. Our current study was designed to gain a better understanding of the impact of short-term senolytic treatment or inflammatory stimulation on lung senescence. The results of our study demonstrate that short term treatment of aged adult mice (20 months of age) with senolytics, quercetin, and dasatinib decreases p16 and p21 expression in lung tissue. Short-term treatment with senolytics also significantly improved the expression of genes associated with genomic instability, telomere attrition, mitochondrial dysfunction, DNA binding, and the inflammatory response. In contrast, in response to low-dose LPS administration, there was increased expression of genes associated with genomic instability, mitochondrial dysfunction, and heightened inflammatory responses in young adult murine lung (3 months of age). Taken together, the results of our current study illustrate the efficacy of senolytic treatment on modulating responses in aged lung and the potential role of chronic low dose inflammation on senescence induction in the lung.

Quercetin as a Dietary Supplementary Flavonoid Alleviates the Oxidative Stress Induced by Lead Toxicity in Male Wistar Rats

Quercetin is a naturally existing plant pigment belonging to the flavonoid group; it is contained in a wide range of vegetables and fruits. The accumulated evidence points to the potential uses of quercetin in protection of some disease conditions. Lead is one of the highly toxicant heavy metals that are widely spread in the environment and implicated in a wide spectrum of industries. No previous study has been reported to evaluate the effect of quercetin on lead toxicity. Therefore, the present study was conducted to elucidate some aspects of quercetin bioactivities in regard to its ability to combat the oxidative stress induced by lead toxicity. For this purpose, a total of sixty male Wistar rats were randomly and equally divided into three groups of 20 animals each; untreated control animals (group 1), lead-exposed animals (group 2; exposed to lead daily by oral gavage at the dose of 80 mg/Kg b.w.), and group 3 of animals, which were exposed to lead and daily received quercetin (10 h gap time between lead exposure and the receiving of quercetin) by oral gavage at the dose of 350 mg/Kg b.w. The experiment period was 8 weeks. All the assayed hematological and biochemical parameters of animals exposed to lead were significantly altered compared with the untreated control levels. Animals exposed to lead (group 2) exhibited significant decrements of the erythrocytic and total leucocytic counts, hemoglobin concentration, packed cell volume percent, total proteins, albumin and globulin. These animals also disclosed significantly decreased levels of antioxidant markers including total thiols, catalase and glutathione. On the other hand, these animals demonstrated significant increments in the levels of bilirubin, urea, creatinine, BUN, serum enzymes, H₂O₂ and MDA. Animals exposed to lead and given quercetin (group 3) exhibited improvement of these parameters, which were brought back at varying degrees toward the untreated control levels. Basing on the improvements of the assayed hematological and biochemical parameters, it was concluded that quercetin as a dietary supplement can act efficiently as an antioxidant to counteract the oxidative stress induced by lead toxicity and to maintain the oxidant antioxidant balance.

The potential role of scavenger receptor B type I (SR-BI) in SARS-CoV-2 infection

Scavenger receptor type B I (SR-BI), the major receptor for high-density lipoprotein (HDL) mediates the delivery of cholesterol ester and cholesterol from HDL to the cell membrane. SR-BI is implicated as a receptor for entry of severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2). SR-BI is colocalized with the angiotensin-converting enzyme 2 (ACE2) increasing the binding and affinity of SARS-CoV-2 to ACE2 with subsequent viral internalization. SR-BI regulates lymphocyte proliferation and the release of pro-inflammatory cytokines from activated macrophages and lymphocytes. SR-BI is reduced during COVID-19 due to consumption by SARS-CoV-2 infection. COVID-19-associated inflammatory changes and high angiotensin II (AngII) might be possible causes of repression of SR-BI in SARS-CoV-2 infection. In conclusion, the downregulation of SR-BI in COVID-19 could be due to direct invasion by SARS-CoV-2 or through upregulation of pro-inflammatory cytokines, inflammatory signaling pathways, and high circulating AngII. Reduction of SR-BI in COVID-19 look like ACE2 may provoke COVID-19 severity through exaggeration of the immune response. Further studies are invoked to clarify the potential role of SR-BI in the pathogenesis of COVID-19 that could be protective rather than detrimental.

Mode of Action of Heat Shock Protein (HSP) Inhibitors against Viruses through Host HSP and Virus Interactions

Misfolded proteins after stress-induced denaturation can regain their functions through correct re-folding with the aid of molecular chaperones. As a molecular chaperone, heat shock proteins (HSPs) can help client proteins fold correctly. During viral infection, HSPs are involved with replication, movement, assembly, disassembly, subcellular localization, and transport of the virus via the formation of macromolecular protein complexes, such as the viral replicase complex. Recent studies have indicated that HSP inhibitors can inhibit viral replication by interfering with the interaction of the virus with the HSP. In this review, we describe the function and classification of HSPs, the transcriptional mechanism of HSPs promoted by heat shock factors (HSFs), discuss the interaction between HSPs and viruses, and the mode of action of HSP inhibitors at two aspects of inhibiting the expression of HSPs and targeting the HSPs, and elaborate their potential use as antiviral agents.

Specialized metabolites from plants as a source of new multi-target antiviral drugs: a systematic review

Viral infections have always been the main global health challenge, as several potentially lethal viruses, including the hepatitis virus, herpes virus, and influenza virus, have affected human health for decades. Unfortunately, most licensed antiviral drugs are characterized by many adverse reactions and, in the long-term therapy, also develop viral resistance; for these reasons, researchers have focused their attention on investigating potential antiviral molecules from plants. Natural resources indeed offer a variety of specialized therapeutic metabolites that have been demonstrated to inhibit viral entry into the host cells and replication through the regulation of viral absorption, cell receptor binding, and competition for the activation of intracellular signaling pathways. Many active phytochemicals, including flavonoids, lignans, terpenoids, coumarins, saponins, alkaloids, etc., have been identified as potential candidates for preventing and treating viral infections. Using a systematic approach, this review summarises the knowledge obtained to date on the in vivo antiviral activity of specialized metabolites extracted from plant matrices by focusing on their mechanism of action.

Food Plant Secondary Metabolites Antiviral Activity and Their Possible Roles in SARS-CoV-2 Treatment: An Overview

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.