Treat Influenza Virus Research Articles

Host-specific SRSF7 regulates polymerase activity and replication of influenza A virus

Avian influenza viruses crossing the host barrier to infect humans have caused great panic in human society and seriously threatened public health. Herein, we revealed that knockdown of SRSF7 significantly down-regulated influenza virus titers and viral protein expression. We further observed for the first time that human SRSF7, but not avian SRSF7, significantly inhibited polymerase activity (PB2627E). Molecular mapping demonstrated that amino acids 206 to 228 of human SRSF7 play a decisive role in regulating the polymerase activity, which contains the amino acid motif absent in avian SRSF7. Importantly, our results illustrated that the PB2627K-encoding influenza virus induces SRSF7 protein degradation more strongly via the lysosome pathway and not via the proteasome pathway. Functional enrichment analysis of SRSF7-related KEGG pathways indicated that SRSF7 is closely related to cell growth and death. Lastly, our results showed that knocking down SRSF7 interferes with normal polymerase activity. Taken together, our results advance our understanding of interspecies transmission and our findings point out new targets for the development of drugs preventing or treating influenza virus infection.

Synergistic activity of an RNA polymerase PA-PB1 interaction inhibitor with oseltamivir against human and avian influenza viruses in cell culture and in ovo

In search of novel therapeutic options to treat influenza virus (IV) infections, we previously identified a series of inhibitors that act by disrupting the interactions between the PA and PB1 subunits of the viral RNA polymerase. These compounds showed broad-spectrum antiviral activity against human influenza A and B viruses and a high barrier to the induction of drug resistance in vitro. In this short communication, we investigated the effects of combinations of the PA-PB1 interaction inhibitor 54 with oseltamivir carboxylate (OSC), zanamivir (ZA), favipiravir (FPV), and baloxavir marboxil (BXM) on the inhibition of influenza A and B virus replication in vitro. We observed a synergistic effect of the 54/OSC and 54/ZA combinations and an antagonistic effect when 54 was combined with either FPV or BXM. Moreover, we demonstrated the efficacy of 54 against highly pathogenic avian influenza viruses (HPAIVs) both in cell culture and in the embryonated chicken eggs model. Finally, we observed that 54 enhances OSC protective effect against HPAIV replication in the embryonated eggs model. Our findings represent an advance in the development of alternative therapeutic strategies against both human and avian IV infections.

Exploring the immune-inflammatory mechanism of Maxing Shigan Decoction in treating influenza virus A-induced pneumonia based on an integrated strategy of single-cell transcriptomics and systems biology.

Influenza is an acute respiratory infection caused by influenza virus. Maxing Shigan Decoction (MXSGD) is a commonly used traditional Chinese medicine prescription for the prevention and treatment of influenza. However, its mechanism remains unclear. The mice model of influenza A virus pneumonia was established by nasal inoculation. After 3days of intervention, the lung index was calculated, and the pathological changes of lung tissue were detected by HE staining. Firstly, transcriptomics technology was used to analyze the differential genes and important pathways in mouse lung tissue regulated by MXSGD. Then, real-time fluorescent quantitative PCR (RT-PCR) was used to verify the changes in mRNA expression in lung tissues. Finally, intestinal microbiome and intestinal metabolomics were performed to explore the effect of MXSGD on gut microbiota. The lung inflammatory cell infiltration in the MXSGD group was significantly reduced (p < 0.05). The results of bioinformatics analysis for transcriptomics results show that these genes are mainly involved in inflammatory factors and inflammation-related signal pathways mediated inflammation biological modules, etc. Intestinal microbiome showed that the intestinal flora Actinobacteriota level and Desulfobacterota level increased in MXSGD group, while Planctomycetota in MXSGD group decreased. Metabolites were mainly involved in primary bile acid biosynthesis, thiamine metabolism, etc. This suggests that MXSGD has a microbial-gut-lung axis regulation effect on mice with influenza A virus pneumonia. MXSGD may play an anti-inflammatory and immunoregulatory role by regulating intestinal microbiome and intestinal metabolic small molecules, and ultimately play a role in the treatment of influenza A virus pneumonia.

Platycodin D facilitates antiviral immunity through inhibiting cytokine storm via targeting K63-linked TRAF6 ubiquitination.

Influenza virus infection is a worldwide challenge that causes heavy burdens on public health. The mortality rate of severe influenza patients is often associated with hyperactive immunological abnormalities characterized by hypercytokinemia. Due to the continuous mutations and the occurrence of drug-resistant influenza virus strains, the development of host-directed immunoregulatory drugs is urgently required. Platycodon grandiflorum is among the top 10 herbs of traditional Chinese medicine used to treat pulmonary diseases. As one of the major terpenoid saponins extracted from Platycodon grandiflorum, Platycodin D (PD) has been reported to play several roles, including anti-inflammation, analgesia, anti-cancer, hepatoprotection, and immunoregulation. However, the therapeutic roles of PD to treat influenza virus infection remains unknown. Here, we show that PD can protect the body weight loss in severely infected influenza mice, alleviate lung damage, and thus improve the survival rate. More specifically, PD protects flu mice via decreasing the immune cell infiltration into lungs and downregulating the overactivated inflammatory response. Western blot and immunofluorescence assays exhibited that PD could inhibit the activation of TAK1/IKK/NF-κB and MAPK pathways. Besides that, CETSA, SPR and immunoprecipitation assays indicated that PD binds with TRAF6 to decrease its K63 ubiquitination after R837 stimulation. Additionally, siRNA interference experiments exhibited that PD could inhibit the secretion of IL-1β and TNF-α in TRAF6-dependent manner. Altogether, our results suggested that PD is a promising drug candidate for treating influenza. Our study also offered a scientific explanation for the commonly used Platycodon grandiflorum in many anti-epidemic classic formulas. Due to its host-directed regulatory role, PD may serve as an adjuvant therapeutic drug in conjunction with other antiviral drugs to treat the flu.

Comparing Microcrystal Electron Diffraction (MicroED) and X-ray crystallography as methods for structure determination of Oseltamivir phosphate

Oseltamivir phosphate is a pharmaceutical used in the treatment of influenza viruses. Panče Naumov et al. took two years of dedicated single crystal cultivation and successfully obtained low-quality single crystals through a diffusion method. Cultivation of Oseltamivir phosphate single crystals was proved to be difficult and can extend over several months or more. We employed microcrystalline electron diffraction (MicroED) for direct powder measurements, eliminating the need for lengthy single-crystal cultivation, and the time to obtain the molecular structure of Oseltamivir phosphate was shortened from several months to five hours. Comparative analyses of single crystal (Crystal 1) and MicroED (Crystal 2) results revealed equivalent crystal structures, with minimal differences in hydrogen bond distances, identical powder X-ray diffraction patterns, and negligible variations in Hirshfeld surface analysis. The differential scanning calorimetry (DSC) analysis showcased a higher melting point of Oseltamivir phosphate (206.0 °C) than Oseltamivir (110.7 °C), indicating that Oseltamivir phosphate had high temperature stability, and may result in the selection of Oseltamivir phosphate as a formulation form. The study establishes and verifies a congruence between MicroED detection and traditional single-crystal detection methods and may be applied in the elucidation of compound structures and the surveillance of drug polymorphism.

Progress of Influenza Viruses and Inhibitors.

Influenza is an acute respiratory disease caused by influenza viruses. It has the characteristics of fast transmission and strong infectivity, and it does great harm to human health and survival. It is estimated that the seasonal influenza epidemics every year will cause about one billion cases of infections and hundreds of thousands of deaths worldwide, while influenza A virus is the leading cause of infection and death. Currently, the main drugs used in clinics to treat influenza viruses are neuraminidase inhibitors, and these drugs have shown excellent efficacy in treating influenza viruses. However, various mutant strains have developed resistance to these effective drugs in clinics (such as the subtype mutant strains of H274Y in H1N1 or H5N1 and E119V in H3N2 have developed resistance to Oseltamivir). Influenza viruses mutate frequently, and new viral strains are constantly discovered, and the pandemics will break out at any time. Therefore, it is urgent to develop efficient and broad-spectrum drugs to prevent and treat the influenza pandemic caused by the emerging new subtypes. This review focuses on describing the pandemic history, the structure, function and prevention methods of influenza viruses and the progress of the development of anti-influenza drugs, to provide the reference for prevention and treatment of influenza viruses and development of influenza virus inhibitors.

Arbidol attenuates liver fibrosis and activation of hepatic stellate cells by blocking TGF-β1 signaling

Chronic liver diseases (CLD) impact over 800 million people globally, causing about 2 million deaths annually. Arbidol (ARB), an indole-derivative used to treat influenza virus infection, was extensively used during COVID-19 pandemic in China. In recent years, studies have shown that ARB, compared to other antiviral drugs, exhibits greater liver-protective efficacy, indicating a potential hepatoprotective effect beyond its antiviral activity. However, the mechanism remains unclear. In this study, we investigated the impact of ARB on liver injury/fibrosis in bile duct ligated (BDL) mice and its effect on spontaneous and transforming growth factor β1 (TGF-β1)-induced activation of primary cultured hepatic stellate cells (HSCs). Oral administration of ARB significantly ameliorated BDL-induced liver injury/fibrosis as reflected by decreased serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), reduced collagen deposition, and diminished mRNA expression of fibrosis markers. ARB notably inhibited spontaneous and TGF-β1-induced activation of primary cultured HSCs. Moreover, ARB also drastically attenuated mRNA expression levels of platelet-derived growth factor receptor (Pdgfr), transforming growth factor-beta receptor (Tgfbr) 1, Tgfbr2, matrix metalloproteinase (Mmp)-2, and Mmp-9 in activated HSCs. We further demonstrate that ARB mitigated Smad2/3 phosphorylation in both TGF-β1 treated HSCs and BDL mice. These data together demonstrate that the therapeutic efficacy of ARB on liver fibrosis is independent of its antiviral activity and likely is achieved by blocking TGF-β1 signaling-mediated HSC activation.

Synergistic Therapeutic Effects and Immunoregulatory Mechanism of Maxing Shigan Decoction Combined with Sijunzi Decoction on Viral Pneumonia in Mice.

Influenza is defined in traditional Chinese medicine (TCM) as an epidemic febrile illness and is usually treated with herbal compound formulas under the guidance of the "Qu Xie and Fu Zheng" theories. Ma Xing Shi Gan Tang (MXSGD) is a prominent remedy for clearing heat and detoxifying toxins in the clinical treatment of influenza in TCM, playing the role of "Qu Xie." Si Jun Zi Tang (SJZD) is recognized as one of the "Fu Zheng" formulas for strengthening the spleen and nourishing the stomach, with immunomodulatory effects. In this study, we followed the principles of "Qu Xie and Fu Zheng" to explore the effects of MXSGD combined with SJZD on viral pneumonia and its mechanism. Results showed that the couse of MXSGD and SJZD was effective in reducing the mortality rates and severity of lung pathology in lethally infected FM1 mice compared to the use of either drug alone. Moreover, further research demonstrated that the combined use suppressed TLRs and NLRP3 inflammatory signaling pathways at 4 dpi while promoting them at 7 dpi. At 10 dpi, there was a significant increase in CD11c+ and CD103+ DCs in the lungs. Together, SJZD improved the therapeutic effectiveness of MXSGD in treating influenza virus pneumonia than when used alone. MXSGD and SJZD exhibit synergistic effects in the treatment of influenza, as evidenced by the inhibition of TLR7 and NLRP3 inflammatory pathways early in the infection and facilitation of the response later. They also increase CD11c+ and CD103+ DC levels, as well as balancing Th1/Th2 cytokines.

Engineering of novel hemagglutinin biosensors for rapid detection and drug screening of Influenza A H7N9 virus

New pathogenic influenza virus strains are constantly emerging, posing a serious risk to both human health and economic growth. To effectively control the spread of this virus, there is an urgent need for early, rapid, sensitive, simple, and cost-effective detection technologies, as well as new and effective antiviral drugs. In this study, we have successfully achieved a significant milestone by successfully fusing the H7N9 influenza virus hemagglutinin (HA) protein with the nano-luciferase component, resulting in the development of a novel set of biosensors. This remarkable achievement marks the first instance of utilizing this biosensor technology for influenza antibody detection. Our biosensor technology also has the potential to facilitate the development of antiviral drugs targeting specific epitopes of the HA protein, providing a promising avenue for the treatment of H7N9 influenza virus infections. Furthermore, our biosensors have broad applications beyond H7N9 influenza virus detection, as they can be expanded for the detection of other pathogens and drug screening applications in the future. By providing a novel and effective solution to the detection and treatment of influenza viruses, our biosensors have the potential to revolutionize the field of infectious disease control.

Comparison of clinical efficacy and safety of baloxavir marboxil versus oseltamivir as the treatment for influenza virus infections: A systematic review and meta-analysis

IntroductionBaloxavir marboxil (BXM), a newly developed cap-dependent endonuclease inhibitor, is widely used to treat influenza virus infections in inpatients and outpatients. A previous meta-analysis included only outpatients and patients suspected of having an influenza virus infection based on clinical symptoms. However, whether BXM or oseltamivir is safer and more effective for inpatients remains controversial. Therefore, we conducted a systematic review and meta-analysis validating the effectiveness and safety of BXM versus oseltamivir in inpatients with influenza virus. MethodsThe Scopus, EMBASE, PubMed, Ichushi, and CINAHL databases were systematically searched for articles published until January 2023. The outcomes were mortality, hospitalization period, incidence of BXM- or oseltamivir-related adverse events, illness duration, and changes of virus titers and viral RNA load in patients with influenza virus infections. ResultsTwo randomized controlled trials with 1624 outpatients and two retrospective studies with 874 inpatients were enrolled. No deaths occurred in outpatients treated with BXM or oseltamivir. Among inpatients, BXM reduced mortality (p = 0.06) and significantly shortened hospitalization period (p = 0.01) compared to oseltamivir. In outpatients, BXM had a significantly lower incidence of adverse events (p = 0.03), reductions in influenza virus titers (p < 0.001) and viral RNA loads (p < 0.001), and a tendency to be a shorter illness duration compared with that of oseltamivir (p = 0.27). ConclusionsOur meta-analysis showed that BXM was safer and more effective in patients than oseltamivir; thus, supporting the use of BXM for the initial treatment of patients with proven influenza virus infection.

Schisandra chinensis (Turcz.) Baill. polysaccharide inhibits influenza A virus in vitro and in vivo.

Influenza virus is prone to seasonal spread and widespread outbreaks, which pose important challenges to public health security. Therefore, it is important to effectively prevent and treat influenza virus infection. Schisandra polysaccharide (SPJ) is a polysaccharide derived from the fruit of Schisandra chinensis (Turcz.) Baill. In this study, we evaluated the antiviral activity of SPJ in vitro and in vivo, especially against influenza A virus (IAV) infection. By analyzing SPJ structure and monosaccharide composition, the molecular weight of SPJ was determined to be 115.5 KD, and it is composed of galacturonic acid (89.4%), rhamnose (0.8%), galactose (4.4%), arabinose (3.8%) and glucose (1.7%). Immunofluorescence analysis showed that SPJ treatment reduced the positive rate of viral nucleoproteins in cells, indicating that the compound had an inhibitory effect on influenza virus replication. Furthermore, SPJ therapy improved the survival of infected mice. Lung virus titer assays indicated that SPJ treatment significantly reduced viral-loading in the lung tissue of infected mice, and alleviated the pathological damage caused by influenza virus infection. Moreover, SPJ reduced cytokine expression during influenza virus challenge. In conclusion, SPJ has anti-influenza virus effects, and may have potential as an anti-influenza drug candidate in further clinical studies.

A fully human monoclonal antibody possesses antibody-dependent cellular cytotoxicity (ADCC) activity against the H1 subtype of influenza A virus by targeting a conserved epitope at the HA1 protomer interface.

The DiversitabTM system produces target specific high titer fully human polyclonal IgG immunoglobulins from transchromosomic (Tc) bovines shown to be safe and effective against multiple virulent pathogens in animal studies and Phase 1, 2 and 3 human clinical trials. We describe the functional properties of a human monoclonal antibody (mAb), 38C2, identified from this platform, which recognizes recombinant H1 hemagglutinins (HAs) and induces appreciable antibody-dependent cellular cytotoxicity (ADCC) activity in vitro. Interestingly, 38C2 monoclonal antibody demonstrated no detectable neutralizing activity against H1N1 virus in both hemagglutination inhibition and virus neutralization assays. Nevertheless, this human monoclonal antibody induced appreciable ADCC against cells infected with multiple H1N1 strains. The HA-binding activity of 38C2 was also demonstrated in flow cytometry using Madin-Darby canine kidney cells infected with multiple influenza A H1N1 viruses. Through further investigation with the enzyme-linked immunosorbent assay involving the HA peptide array and 3-dimensional structural modeling, we demonstrated that 38C2 appears to target a conserved epitope located at the HA1 protomer interface of H1N1 influenza viruses. A novel mode of HA-binding and in vitro ADCCactivity pave the way for further evaluation of 38C2 as a potential therapeutic agent to treat influenza virus infections in humans.

Highly Cross-Reactive and Protective Influenza A Virus H3N2 Hemagglutinin- and Neuraminidase-Specific Human Monoclonal Antibodies.

Due to antigenic drift and shift of influenza A viruses (IAV) and the tendency to elicit predominantly strain-specific antibodies, humanity remains susceptible to new strains of seasonal IAV and is at risk from viruses with pandemic potential for which limited or no immunity may exist. The genetic drift of H3N2 IAV is specifically pronounced, resulting in two distinct clades since 2014. Here, we demonstrate that immunization with a seasonal inactivated influenza vaccine (IIV) results in increased levels of H3N2 IAV-specific serum antibodies against hemagglutinin (HA) and neuraminidase (NA). Detailed analysis of the H3N2 B cell response indicated expansion of H3N2-specific peripheral blood plasmablasts 7 days after IIV immunization which expressed monoclonal antibodies (MAbs) with broad and potent antiviral activity against many H3N2 IAV strains as well as prophylactic and therapeutic activity in mice. These H3N2-specific B cell clonal lineages persisted in CD138+ long-lived bone marrow plasma cells. These results demonstrate that IIV-induced H3N2 human MAbs can protect and treat influenza virus infection in vivo and suggest that IIV can induce a subset of IAV H3N2-specific B cells with broad protective potential, a feature that warrants further study for universal influenza vaccine development. IMPORTANCE Influenza A virus (IAV) infections continue to cause substantial morbidity and mortality despite the availability of seasonal vaccines. The extensive genetic variability in seasonal and potentially pandemic influenza strains necessitates new vaccine strategies that can induce universal protection by focusing the immune response on generating protective antibodies against conserved targets within the influenza virus hemagglutinin and neuraminidase proteins. We have demonstrated that seasonal immunization with inactivated influenza vaccine (IIV) stimulates H3N2-specific monoclonal antibodies in humans that are broad and potent in their neutralization of virus in vitro. These antibodies also provide protection from H3N2 IAV in a mouse model of infection. Furthermore, they persist in the bone marrow, where they are expressed by long-lived antibody-producing plasma cells. This significantly demonstrates that seasonal IIV can induce a subset of H3N2-specific B cells with broad protective potential, a process that if further studied and enhanced could aid in the development of a universal influenza vaccine.

Bioassay guided isolation of caffeoylquinic acids from the leaves of Ilex pubescens Hook. et Arn. and investigation of their anti-influenza mechanism.

Ilex pubescens Hook. et Arn. (Maodongqing, MDQ) is a common herbal tea ingredient in Southern China for heat clearance and anti-inflammation. Our preliminary screening showed that 50% ethanol extract of its leaves has anti-influenza virus activity. In this report, we proceed to identify the active components and clarify the related anti-influenza mechanisms. We aim to isolate and identify the anti-influenza virus phytochemicals from the extract of the MDQ leaves, and study their anti-influenza virus mechanism. Plaque reduction assay was used to test the anti-influenza virus activity of fractions and compounds. Neuraminidase inhibitory assay was used to confirm the target protein. Molecular docking and reverse genetics were used to confirm the acting site of caffeoylquinic acids (CQAs) on viral neuraminidase. Eight CQAs, 3,5-di-O-caffeoylquinic acid methyl ester (Me 3,5-DCQA), 3,4-di-O-caffeoylquinic acid methyl ester (Me 3,4-DCQA), 3,4,5-tri-O-caffeoylquinic acid methyl ester (Me 3,4,5-TCQA), 3,4,5-tri-O-caffeoylquinic acid (3,4,5-TCQA), 4,5-di-O-caffeoylquinic acid (4,5-DCQA), 3,5-di-O-caffeoylquinic acid (3,5-DCQA), 3,4-di-O-caffeoylquinic acid (3,4-DCQA), and 3,5-di-O-caffeoyl-epi-quinic acid (3,5-epi-DCQA) were identified from the MDQ leaves, in which Me 3,5-DCQA, 3,4,5-TCQA and 3,5-epi-DCQA were isolated for the first time. All these eight compounds were found to inhibit neuraminidase (NA) of influenza A virus. The results of molecular docking and reverse genetics indicated that 3,4,5-TCQA interacted with Tyr100, Gln412 and Arg419 of influenza NA, and a novel NA binding groove was found. Eight CQAs isolated from the leaves of MDQ were found to inhibit influenza A virus. 3,4,5-TCQA was found to interact with Tyr100, Gln412 and Arg419 of influenza NA. This study provided scientific evidence on the use of MDQ for treating influenza virus infection, and laid the foundation for the development of CQA derivatives as potential antiviral agents.

Fabrication and Evaluation of Rimantadine Loaded Niosomes

Influenza virus is a highly contagious zoonotic respiratory disease that causes seasonal outbreaks each year and unpredictable pandemics occasionally with high morbidity and mortality rates, posing a great threat to public health worldwide. Besides the limited effect of vaccines, the problem is exacerbated by the lack of drugs with strong antiviral activity against all flu strains. Rimantadine is one of the effective anti-viral drugs that is used in treating influenza virus. In present study niosomes of Rimantadine were developed by ether injection method. Total 6 formulations were prepared by altering ratios of span 60 and cholesterol. The prepared formulations were evaluated for different parameters. In vitro drug release studies were carried out for all the formulations and among five formulations F5 was found to have highest drug release. Prepared niosomes were incorporated in gel and evaluation studies like pH, homogenicity, viscosity and spreadability were carried out. All the parameters were found satisfactory. It was compared with marketed gel. The former has shown drug release till 12 h whereas the latter has shown only till 6 h. Thus, sustained release of drug loaded niosomes was proved.

PIONEER trial: favipiravir to treat moderate COVID-19

As the COVID-19 pandemic claimed lives across the globe, several randomised clinical trials were conducted to evaluate the safety and efficacy of investigational and repurposed therapeutics for the treatment of COVID-19. As a result, a number of new antivirals are now licensed to treat COVID-19, such as nirmatrelvir–ritonavir (Paxlovid), molnupiravir, and remdesivir.1–3 Favipiravir is an RNA-dependant RNA polymerase inhibitor with activity against a range of RNA viruses. The agent is licensed in Japan to treat influenza virus and has been studied and subsequently used to treat SARS-CoV-2 infection in several Asian countries.

A novel E198K substitution in the PA gene of influenza A virus with reduced susceptibility to baloxavir acid.

Baloxavir acid (BXA), the active compound in baloxavir marboxil (BXM), reduces the propagation of influenza A and B viruses by inhibiting the cap-dependent endonuclease activity of the polymerase acidic (PA) subunit. Although BXM has been used to treat influenza virus infections, recently, there has been general concern about the emergence of viruses with low susceptibility to BXA. Here, we identified a novel PA subunit substitution, PA E198K, that reduced susceptibility to BXA. The IC50 of BXA toward influenza A viruses containing PA E198K increased approximately 2- to 6-fold. These findings help to understand the mechanism by which PA substitutions reduce susceptibility to BXA.

Exploration of the Mechanism of Lianhua Qingwen in Treating Influenza Virus Pneumonia and New Coronavirus Pneumonia with the Concept of "Different Diseases with the Same Treatment" Based on Network Pharmacology.

The 31 main components of Lianhua Qingwen (LHQW) were obtained through a literature and database search; the components included glycyrrhizic acid, emodin, chlorogenic acid, isophoroside A, forsythia, menthol, luteolin, quercetin, and rutin. Sixty-eight common targets for the treatment of novel coronavirus pneumonia (NCP) and influenza virus pneumonia (IVP) were also obtained. A “component-target-disease” network was constructed with Cytoscape 3.2.1 software, and 20 key targets, such as cyclooxygenase2 (COX2), interleukin-6 (IL-6), mitogen-activated protein kinase14 (Mapk14), and tumor necrosis factor (TNF), were screened from the network. The David database was used to perform a Kyoto Encyclopedia of Genes and Genomes (KEGG) signal pathway enrichment analysis and gene ontology (GO) biological process enrichment. Results showed that the key targets of LHQW in the treatment of NCP and IVP mainly involved biological processes, such as immune system process intervention, cell proliferation, apoptosis and invasion, toxic metabolism, cytokine activity, and regulation of the synthesis process. KEGG enrichment analysis revealed that 115 signalling pathways were related to the treatment of LHQW. Amongst them, IL-17, T cell receptor, Th17 cell differentiation, TNF, toll-like receptor, MAPK, apoptosis, and seven other signalling pathways were closely related to the occurrence and development of NCP and IVP. Molecular docking showed that each component had different degrees of binding with six targets, namely, 3C-like protease (3CL), angiotensin-converting enzyme 2 (ACE2), COX2, hemagglutinin (HA), IL-6, and neuraminidase (NA). Rutin, isoforsythiaside A, hesperidin and isochlorogenic acid B were the best components for docking with the six core targets. The first five components with the best docking results were isoforsythiaside, hesperidin, isochlorogenic acid B, forsythin E, and quercetin. In conclusion, LHQW has many components, targets, and pathways. The findings of this work can provide an important theoretical basis for determining the mechanism of LHQW in treating NCP and IVP.

Potent antiviral activity of the extract of Elaeocarpus sylvestris against influenza A virus in vitro and in vivo

BackgroundElaeocarpus sylvestris (Lour.) Poir. (Elaeocarpaceae) belongs to a genus of tropical and semitropical evergreen trees, which has known biological activities such as antiviral and immunomodulatory activities. However, its antiviral potential against influenza virus infection remains unknown. PurposeIn this study, we investigated the antiviral activity of the 50% aqueous ethanolic extract of E. sylvestris (ESE) against influenza A virus (IAV) infection, which could lead to the development of novel phytomedicine to treat influenza virus infection. MethodsTo investigate the in vitro antiviral activity of ESE and its main ingredients, 1,​2,​3,​4,​6-​penta-​O-​galloyl-β-d-glucose (PGG) and geraniin (GE), the levels of viral RNAs, proteins, and infectious viral particles in IAV-infected MDCK cells were analyzed. Molecular docking analysis was performed to determine the binding energy of PGG and GE for IAV proteins. To investigate in vivo antiviral activity, IAV-infected mice were treated intranasally or intragastrically with ESE, PGG, or GE. ResultsESE and its gallate main ingredients (PGG and GE) strongly inhibited the production of viral RNAs, viral proteins, and infectious viral particles in vitro. Also through the viral attachment on cells, polymerase activity, signaling pathway, we revealed the ESE, PGG, and GE inhibit multiple steps of IAV replication. Molecular docking analysis revealed that PGG and GE could interact with 12 key viral proteins (M1, NP, NS1 effector domain (ED), NS1 RNA-binding domain (RBD), HA pocket A, HA receptor-binding domain (RBD), NA, PA, PB1, PB2 C-terminal domain, PB2 middle domain, and PB2 cap-binding domain) of IAV proteins with stable binding energy. Furthermore, intranasal administration of ESE, PGG, or GE protected mice from IAV-induced mortality and morbidity. Importantly, oral administration of ESE suppressed IAV replication and the expression of inflammatory cytokines such as IFN-γ, TNF-α, and IL-6 in the lungs to a large extent. ConclusionESE and its major components (PGG and PE) exhibited strong antiviral activity in multiple steps against IAV infection in silico, in vivo, and in vitro. Therefore, ESE could be used as a novel natural product derived therapeutic agent to treat influenza virus infection.

Orally dissolving strip for treatment of influenza virus

Orally dissolving strip for treatment of influenza virus