Chinese herbal medicine compound Yi-Zhi-Hao pellet inhibits replication of influenza virus infection through activation of heme oxygenase-1

Elucidating the antiviral effects of a novel compound throat anti-viral through metabolomics and network pharmacology: A study on infectious bronchitis virus in poultry

Infectious bronchitis virus (IBV) is a major pathogen that causes significant economic losses in the global poultry industry. Current vaccination strategies provide only partial protection, highlighting the need for more effective prevention and treatment methods. This study aimed to develop a novel compound throat anti-viral (CTA) from natural plants using data from the Traditional Chinese Medicine Inheritance System and identification through liquid chromatography-mass spectrometry. CTA demonstrated substantial anti-IBV effects both in vitro and in vivo studies. In vitro, CTA significantly inhibited IBV multiplication and alleviated the pathological lesions in chicken embryonic kidney cells, tracheal rings, and chicken embryos. In vivo, a seven-day treatment with CTA obtained much milder clinical signs, enhanced growth performance, and better immune organ indices in infected chickens. Additionally, CTA treatment reduced IBV levels in the trachea and lungs and increased specific antibody titers. CTA also maintained body homeostasis, exhibiting strong antioxidant and anti-inflammatory properties that mitigated respiratory tract damage. Metabolomics and network pharmacology analyses, revealed that CTA's antiviral effects are mediated through the FoxO signaling pathway. This study successfully developed an effective prescription database based on the Traditional Chinese Medicine Inheritance System and validated the antiviral efficacy of CTA through comprehensive in vitro and in vivo experiments. The findings elucidated the mechanisms of CTA's action, particularly through the FoxO signaling pathway, and highlighted its potential for clinical application as a novel antiviral treatment for IBV in the poultry industry.

Decoction derived from Allium ascalonicum L. bulbs and Sojae Semen Praeparatum alleviates wind-cold-type common cold via Nrf2/HO-1 pathway and modulation of Lactobacillus murinus level

Background

Cong-Chi decoction (CCD) is made using Allium ascalonicum L. (shallot) bulbs and Sojae Semen Praeparatum (SSP). Shallot bulbs and SSP are both used regularly in traditional Chinese medicine; however, there are no recent pharmacological studies on their synergistic effects. Despite their roles in the treatment of the common cold for thousands of years, their pharmacological mechanisms of action against wind-cold-type common cold are yet to be explored comprehensively.

Methods

A mouse model was standardized using wind-cold modeling equipment to study the anti-inflammatory, antioxidant, and antiapoptotic effects of CCD. Then, 16S rRNA sequencing was employed to analyze the association between Lactobacillus murinus and changes in body temperature. Additionally, the antipyretic effects of L. murinus were validated via animal experiments.

Results

The results indicate that CCD improves the symptoms of wind-cold by reducing fever, levels of pro-inflammatory factors, and cellular apoptosis, as well as increasing the blood leukocyte and lymphocyte counts, thereby alleviating lung tissue damage. The effects of CCD are mediated by upregulation of pulmonary Nrf2 and HO-1 expressions, thereby reducing oxidative damage in the lungs, in addition to other anti-inflammatory mechanisms. Furthermore, CCD increases the abundance of L. murinus in the intestinal tract. The animal experiments confirm that L. murinus ameliorates fever in mice.

Conclusion

CCD exhibits remarkable antioxidant and anti-inflammatory properties for effectively treating wind-cold-type common cold. Furthermore, its regulatory effects on L. murinus represent a novel mechanism for product development.

Licochalcone A plays dual antiviral roles by inhibiting RSV and protecting against host damage

Respiratory syncytial virus (RSV) causes lower respiratory tract diseases and bronchiolitis in children and elderly individuals. There are no effective drugs currently available to treat RSV infection. In this study, we report that Licochalcone A (LCA) can inhibit RSV replication and mitigate RSV-induced cell damage in vitro, and that LCA exerts a protective effect by reducing the viral titer and inflammation in the lungs of infected mice in vivo. We suggest that the mechanism of action occurs through pathways of antioxidant stress and inflammation. Further mechanistic results demonstrate that LCA can induce nuclear factor erythroid 2-related factor 2 (Nrf2) translocation into the nucleus, activate heme oxygenase 1 (HO-1), and inhibit reactive oxygen species-induced oxidative stress. LCA also works to reverse the decrease in I-kappa-B-alpha (IкBα) levels caused by RSV, which in turn inhibits inflammation through the associated nuclear factor kappa B and tumor necrosis factor-α signaling pathways. The combined action of the two cross-talking pathways protects hosts from RSV-induced damage. To conclude, our study is the first of its kind to establish evidence of LCA as a viable treatment for RSV infection.

Phenolic compound SG-1 from Balanophora harlandii and its derivatives exert anti-influenza A virus activity via activation of the Nrf2/HO-1 pathway

Influenza A virus (IAV) is one of the leading causes of respiratory illness and continues to cause pandemics around the world. Against this backdrop, drug resistance poses a challenge to existing antiviral drugs, and hence, there is an urgent need for developing new antiviral drugs. In this study, we obtained a phenolic compound SG-7, a derivative of natural compound 2-hydroxymethyl-1,4-hydroquinone, which exhibits inhibitory activity toward a panel of influenza viruses and has low cellular toxicity. Mechanistic studies have shown that SG-7 exerts its anti-IAV properties by acting on the virus itself and modulating host signaling pathways. Namely, SG-7 targets the HA2 subunit of hemagglutinin (HA) to block the fusion of viral-cellular membranes and inhibits IAV-induced oxidative stress and overexpression of pro-inflammatory factors by activating the Nrf2/HO-1 pathway and reducing NF-κB activation. In addition, SG-7 can enhance type I IFN antiviral response by inducing Nrf2 expression. Importantly, SG-7 showed the ability to inhibit viral replication in the lungs of IAV-infected mice and reduce their mortality. Therefore, SG-7 may be a promising lead compound for anti-influenza drug development.

Qingfei Jiedu Granules fight influenza by regulating inflammation, immunity, metabolism, and gut microbiota

Background and aim

Qingfei Jiedu Granules (QFJD) are a new Traditional Chinese Medicine (TCM) which has been clinically used against coronavirus pneumonia in China. In this study, the therapeutic effect and the underlying mechanisms of QFJD against influenza were investigated.

Experimental procedure

Pneumonia mice were induced by influenza A virus. Survival rate, weight loss, lung index and lung pathology were measured to evaluate the therapeutic effect of QFJD. The expression of inflammatory factors and lymphocytes was used to assess anti-inflammatory and immunomodulatory effect of QFJD. Gut microbiome analysis was performed to decipher the potential effect of QFJD on intestinal microbiota. Metabolomics approach was conducted to explore the overall metabolic regulation of QFJD.

Result and conclusion

QFJD shows a significant therapeutic effect on the treatment of influenza and the expression of many pro-inflammatory cytokines were obviously inhibited. QFJD also markedly modulates the level of T and B lymphocytes. The high-dose QFJD has shown similar therapeutic efficiency compared to positive drugs. QFJD profoundly enriched Verrucomicrobia and maintained the balance between Bacteroides and Firmicutes. QFJD associated with 12 signaling pathways in metabolomics study, 9 of which were the same as the model group and were closely related to citrate cycle and amino acid metabolism.To sum up, QFJD is a novel and promising drug against influenza. It can regulate inflammation, immunity, metabolism, and gut microbiota to fight influenza. Verrucomicrobia shows great potential to improve influenza infection and may be an important target.

Multi-Omics-Guided Discovery of Omicsynins Produced by Streptomyces sp. 1647: Pseudo-Tetrapeptides Active Against Influenza A Viruses and Coronavirus HCoV-229E

Many microorganisms have mechanisms that protect cells against attack from viruses. The fermentation components of Streptomyces sp. 1647 exhibit potent anti-influenza A virus (IAV) activity. This strain was isolated from soil in southern China in the 1970s, but the chemical nature of its antiviral substance(s) has remained unknown until now. We used an integrated multi-omics strategy to identify the antiviral agents from this streptomycete. The antibiotics and Secondary Metabolite Analysis Shell (antiSMASH) analysis of its genome sequence revealed 38 biosynthetic gene clusters (BGCs) for secondary metabolites, and the target BGCs possibly responsible for the production of antiviral components were narrowed down to three BGCs by bioactivity-guided comparative transcriptomics analysis. Through bioinformatics analysis and genetic manipulation of the regulators and a biosynthetic gene, cluster 36 was identified as the BGC responsible for the biosynthesis of the antiviral compounds. Bioactivity-based molecular networking analysis of mass spectrometric data from different recombinant strains illustrated that the antiviral compounds were a class of structural analogues. Finally, 18 pseudo-tetrapeptides with an internal ureido linkage, omicsynins A1-A6, B1-B6, and C1-C6, were identified and/or isolated from fermentation broth. Among them, 11 compounds (omicsynins A1, A2, A6, B1-B3, B5, B6, C1, C2, and C6) are new compounds. Omicsynins B1-B4 exhibited potent antiviral activity against IAV with the 50% inhibitory concentration (IC₅₀) of approximately 1 µmol∙L^-1 and a selectivity index (SI) ranging from 100 to 300. Omicsynins B1-B4 also showed significant antiviral activity against human coronavirus HCoV-229E. By integrating multi-omics data, we discovered a number of novel antiviral pseudo-tetrapeptides produced by Streptomyces sp. 1647, indicating that the secondary metabolites of microorganisms are a valuable source of novel antivirals.

Novel and Alternative Therapeutic Strategies for Controlling Avian Viral Infectious Diseases: Focus on Infectious Bronchitis and Avian Influenza

The growth of poultry farming has enabled higher spread of infectious diseases and their pathogens among different kinds of birds, such as avian infectious bronchitis virus (IBV) and avian influenza virus (AIV). IBV and AIV are a potential source of poultry mortality and economic losses. Furthermore, some pathogens have the ability to cause zoonotic diseases and impart human health problems. Antiviral treatments that are used often lead to virus resistance along with the problems of side effects, recurrence, and latency of viruses. Though target hosts are being vaccinated, the constant emergence and re-emergence of strains of these viruses cause disease outbreaks. The pharmaceutical industry is gradually focusing on plant extracts to develop novel herbal drugs to have proper antiviral capabilities. Natural therapeutic agents developed from herbs, essential oils (EO), and distillation processes deliver a rich source of amalgams to discover and produce new antiviral drugs. The mechanisms involved have elaborated how these natural therapeutics agents play a major role during virus entry and replication in the host and cause inhibition of viral pathogenesis. Nanotechnology is one of the advanced techniques that can be very useful in diagnosing and controlling infectious diseases in poultry. In general, this review covers the issue of the poultry industry situation, current infectious diseases, mainly IB and AI control measures and, in addition, the setup of novel therapeutics using plant extracts and the use of nanotechnology information that may help to control these diseases.

Synthesis and Anti-Influenza Virus Effects of Novel Substituted Polycyclic Pyridone Derivatives Modified from Baloxavir

In this work, a series of novel substituted polycyclic pyridone derivatives were designed and synthesized as potent anti-influenza agents. The cytopathic effect (CPE) assay and cytotoxicity assay indicated that all of the compounds possessed potent anti-influenza virus activity and relatively low cytotoxicity; some of them inhibited the replication of influenza A virus (IAV) at picomolar concentrations. Further studies revealed that, at a concentration of 3 nM, three compounds (10a, 10d, and 10g) could significantly reduce the M2 RNA amounts and M2 protein expression of IAV and inhibit the activity of RNA-dependent RNA polymerase (RdRp). Among them, (R)-12-(5H-dibenzo[a,d][7]annulen-5-yl)-7-hydroxy-3,4,12,12a-tetrahydro-1H-[1,4]oxazino[3,4-c]pyrido[2,1-f][1,2,4]triazine-6,8-dione (10a) was found to be a promising anti-influenza drug candidate with good human liver microsomal stability, as well as with better selectivity index and oral bioavailability than Baloxavir.

Exploring the synergistic mechanism of Gegen Qinlian Decoction on the Wnt signaling pathway using an integrated strategy of network pharmacology and RNA-seq

ETHNOPHARMACOLOGICAL RELEVANCE

Gegen Qinlian Decoction (GQD) (including: Puerariae lobatae (Willd.) Ohwi, radix; (short for Gengen) Glycyrrhiza uralensis Fisch., root and rhizome (short for Gancao), honeyed; Coptis chinensis Franch., rhizome (short for Huanglian); Scutellaria baicalensis Georgi, radix, boiled (short for S. baicalensis) has been widely used to treat inflammatory bowel disease (IBD) and colorectal cancer (CRC). To explore compatibility mechanism of GQD could be of advantage to investigate the complex principle of TCM, which might be conducive to the exploration of the modernization of TCM.

AIM OF REVIEW

In this study, a strategy based on system pharmacology was constructed to uncover the multi-target regulation and compatibility mechanism of GQD on the Wnt signaling pathways.

MATERIAL AND METHODS

The pharmacological network of GQD was constructed by TCMSP, DAVID, Uniprote database. The cell growth inhibitory effects of puerarin (PUE), wogonin (WOG), berberine (BER), and glycyrrhetinic acid (GLY) on SW480 cells were assessed using CCK-8 assay. The multi-target regulation and compatibility mechanism of combination PUE with GLY were examined by RNA-seq, HPLC-QQQ/MS, qRT- PCR and Western blot analysis.

RESULTS

Network pharmacology analysis indicated that PUE, WOG, BER and GLY were the active components in GQD and had a synergistic effect on the targets of the Wnt signaling pathway. Additionally, pharmacological experiments revealed that WOG, BER, and GLY inhibited activity of colorectal cancer (CRC) cell lines SW480 cells, and that PUE only exhibited effective antitumour activity when combined with GLY. CTNNB1, CCND1 and SMAD4 were identified as synergistic targets inhibited by PUE-GLY. Moreover, PUE-GLY could influence the Wnt signaling pathway by upregulating GSK3B and downregulating CTNNB1 synergistically. It also showed that GLY could effectively increase the intracellular content of PUE based on HPLC-QQQ/MS analysis, and this process was achieved by influencing the targets of the membrane's pathway, such as cell adhesion molecules, focal adhesion, and tight junctions.

CONCLUSION

GLY was revealed a multi-target mechanism, which could downregulate CTNNB1 as the active component and intervene in membrane proteins (CDH1, CADM1, ITGB2, ICAM1, ITGA1) as 'guide' in the formulae. Moreover, the mechanism of synergistic antitumour action of PUE (the active component of Monarch drug) and GLY (the active component of Guide drug) on the Wnt signaling pathway was explored systematically. It was a promising breakthrough for elucidating the scientific connotation of the compatibility of TCM formulae and provide a valuable and practicable methodology for clarifying the mechanisms of TCM.

Antiviral effect of fufang yinhua jiedu (FFYH) granules against influenza A virus through regulating the inflammatory responses by TLR7/MyD88 signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Fufang-Yinhua-Jiedu Granules (FFYH) optimized from a Yin-Qiao-San, as traditional Chinese medicine (TCM), was used to treat influenza and upper respiratory tract infection and was recommended for the prevention and treatment of SARS in 2003 and current COVID-19 in Anhui Province in 2020.

AIM OF STUDY

In the clinical studies, FFYH was very effective for the treatment of influenza, but the mechanism of action against influenza A virus remains unclear. In the present study, we investigated the antiviral effect of FFYH against influenza A virus in vitro and vivo. Moreover, the potential mechanism of FFYH against influenza A virus in vivo was investigated for the first time.

MATERIALS AND METHODS

CPE inhibition assay and HA assay were used to evaluate the in vitro antiviral effects of FFYH against influenza A virus H1N1, H3N2, H5N1, H7N9 and H9N2. Mice were used to evaluate the antiviral effect of FFYH in vivo with ribavirin and lianhuaqingwen as positive controls. RT-PCR was used to quantify the mRNA transcription of TNF-α, IL-6, IFN-γ, IP10, and IL-1β mRNA. ELISA was used to examine the expression of inflammatory factors such as TNF-α, IL-6, IFN-γ, IP10, and IL-1β in sera. The blood parameters were analyzed with auto hematology analyzer. Moreover, the potential mechanism of FFYH against influenza A virus in vivo was also investigated.

RESULTS

FFYH showed a broad-spectrum of antiviral activity against H1N1, H3N2, H5N1, H7N9, and H9N2 influenza A viruses. Furthermore, FFYH dose-dependently increased the survival rate, significantly prolonged the median survival time of mice, and markedly reduced lung injury caused by influenza A virus. Also, FFYH significantly improve the sick signs, food taken, weight loss, blood parameters, lung index, and lung pathological changes. Moreover, FFYH could markedly inhibit the inflammatory cytokine expression of TNF-α, IL-6, IFN-γ, IP10, IL-10, and IL-1β mRNA or protein via inhibition of the TLR7/MyD88/NF-κB signaling pathway in vivo.

CONCLUSION

FFYH not only showed a broad-spectrum of anti-influenza virus activity in vitro, but also exhibited a significant protective effect against lethal influenza virus infection in vivo. Furthermore, our results indicated that the in vivo antiviral effect of FFYH against influenza virus may be attributed to suppressing the expression of inflammatory cytokines via regulating the TLR7/MyD88/NF-κB signaling pathway. These findings provide evidence for the clinical treatment of influenza A virus infection with FFYH.

Phytochemical Profiles and their Anti-inflammatory Responses Against Influenza from Traditional Chinese Medicine or Herbs

Traditional Chinese medicine (TCM) or herbs are widely used in the prevention and treatment of viral infectious diseases. However, the underlying mechanisms of TCMs remain largely obscure due to complicated material basis and multi-target therapeutics. TCMs have been reported to display anti-influenza activity associated with immunoregulatory mechanisms by enhancing host antiinfluenza immune responses. Previous studies have helped us understand the direct harm caused by the virus itself. In this review, we have tried to summarize recent progress in TCM-based anti-influenza research on the indirect harmful immune responses caused by influenza viruses. In particular, the phytochemicals from TCMs responsible for molecular mechanisms of action belonging to different classes, including phenolic compounds, flavonoids, alkaloids and polysaccharides, have been identified and demonstrated. In addition, this review focuses on the pharmacological mechanism, e.g., inflammatory responses and the interferon (IFN) signaling pathway, which can provide a theoretical basis and approaches for TCM based anti-influenza treatment.

Physalin B ameliorates nonalcoholic steatohepatitis by stimulating autophagy and NRF2 activation mediated improvement in oxidative stress

Non-alcoholic steatohepatitis (NASH) is the progressive stage of non-alcoholic fatty liver disease that may ultimately lead to cirrhosis and liver cancer, and there are few therapeutic options for its treatment. Physalin B (PB), a withanolide isolated from Physalis species (Solanaceae), exhibits a broad spectrum of biological activities, however, the potential role of PB in NASH has not been evaluated. The present study investigated the protective effects of PB against NASH and further elucidated the mechanisms of PB in hepatic autophagy and oxidative stress in vitro and in vivo. We conducted a series of experiments using methionine-choline deficient (MCD) diet induced NASH mice and cultured L02 cells. Serum markers of liver injury, morphology, and the histology of liver tissues were investigated. Western blot assays and quantitative real-time PCR were used to investigate the hepatoprotective effect of PB. PB significantly ameliorated hepatic injury, including hepatic index, transaminase activities, histology, and inflammation in MCD-induced mice. Moreover, PB markedly increased the expression of P62 and the ratio of LC3Ⅱ/Ⅰ in vitro and in vivo. Furthermore, PB promoted the interaction between endogenous KEAP1 and P62, reduced the interaction between KEAP1 and NRF2, activated the nuclear translocation of NRF2 and NRF2 target gene expression, and ultimately attenuated oxidative stress. In addition, knockdown of P62 blocked PB-mediated activation of NRF2 in L02 cells. These results clearly indicated that PB ameliorated NASH by stimulating autophagy and P62-KEAP1-NRF2 antioxidative signaling, suggesting that PB is expected to become a novel therapeutic drug for NASH.

Quercetin as a Natural Therapeutic Candidate for the Treatment of Influenza Virus

The medical burden caused by respiratory manifestations of influenza virus (IV) outbreak as an infectious respiratory disease is so great that governments in both developed and developing countries have allocated significant national budget toward the development of strategies for prevention, control, and treatment of this infection, which is seemingly common and treatable, but can be deadly. Frequent mutations in its genome structure often result in resistance to standard medications. Thus, new generations of treatments are critical to combat this ever-evolving infection. Plant materials and active compounds have been tested for many years, including, more recently, active compounds like flavonoids. Quercetin is a compound belonging to the flavonols class and has shown therapeutic effects against influenza virus. The focus of this review includes viral pathogenesis as well as the application of quercetin and its derivatives as a complementary therapy in controlling influenza and its related symptoms based on the targets. We also touch on the potential of this class of compounds for treatment of SARS-COV-2, the cause of new pandemic.

New sesquiterpeniod esters form Blumea balsamifera (L.) DC. and their anti-influenza virus activity

Phytochemical studies led to the isolation of five new sesquiterpeniod esters, named balsamiferine N-R, along with ten known compounds (6-15) from the leaves of Blumea balsamifera (L.) DC. The skeletons of nine known sesquiterpeniods belong to guaiane and eudesmane. The structures of the new compounds including their absolute configurations were elucidated by comprehensive spectroscopic analysis, and quantum-chemical electronic circular dichroism (ECD) calculation. Compounds 3 and 4 showed significant inhibitory effects on influenza A virus (H3N2) with IC₅₀ values of 46.23 μg/mL and 38.49 μg/mL, respectively. It was the first report on the anti-influenza A virus constituents from B. balsamifera.

Rapid identification and isolation of neuraminidase inhibitors from mockstrawberry (Duchesnea indica Andr.) based on ligand fishing combined with HR-ESI-Q-TOF-MS

Neuraminidase inhibitors (NAIs) are the mainstay antiviral drugs against influenza infection. In this study, a ligand fishing protocol was developed to screen NAIs using neuraminidase immobilized magnetic beads (NA-MB). After verifying the feasibility of NA-MB with an artificial mixture including NA inhibitors and non-inhibitors, the developed ligand fishing protocol was applied to screen NAIs from the crude extracts of Duchesnea indica Andr. Twenty-four NA binding compounds were identified from the normal butanol (n-BuOH) extract of D. indica as potential NAIs by high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (HPLC–Q-TOF-MS) assisted with Compound Structure Identification (CSI):FingerID, including 12 ellagitannins, 4 brevifolin derivatives, 3 ellagic acid derivatives, and 4 flavonoids. Among them, 9 compounds were isolated and tested for in vitro NA inhibitory activities against NA from Clostridium perfringens, and from oseltamivir sensitive and resistant influenza A virus strains. The results indicate that compound B23 has the NA inhibitory activities in both the oseltamivir sensitive and resistant viral NA, with half maximal inhibitory concentration (IC₅₀) values of 197.9 and 125.4 μmol/L, respectively. Moreover, B23 can obviously reduce the replication of oseltamivir sensitive and resistant viruses in Madin–Darby canine kidney (MDCK) cells at the concentrations of 40 and 200 μmol/L.

•

An efficient ligand fishing protocol was developed to rapidly screen the neuraminidase inhibitors from natural sources.

•

24 potential neuraminidase inhibitors were identified from Duchesnea indica as potential NAIs by HPLC-Q-TOF-MS.

•

One compound can inhibit neuraminidase activities in both the oseltamivir sensitive and resistant virus strains.

Strategies for Targeting SARS CoV-2: Small Molecule Inhibitors-The Current Status

Severe Acute Respiratory Syndrome-Corona Virus-2 (SARS-CoV-2) induced Coronavirus Disease - 19 (COVID-19) cases have been increasing at an alarming rate (7.4 million positive cases as on June 11 2020), causing high mortality (4,17,956 deaths as on June 11 2020) and economic loss (a 3.2% shrink in global economy in 2020) across 212 countries globally. The clinical manifestations of this disease are pneumonia, lung injury, inflammation, and severe acute respiratory syndrome (SARS). Currently, there is no vaccine or effective pharmacological agents available for the prevention/treatment of SARS-CoV2 infections. Moreover, development of a suitable vaccine is a challenging task due to antibody-dependent enhancement (ADE) and Th-2 immunopathology, which aggravates infection with SARS-CoV-2. Furthermore, the emerging SARS-CoV-2 strain exhibits several distinct genomic and structural patterns compared to other coronavirus strains, making the development of a suitable vaccine even more difficult. Therefore, the identification of novel small molecule inhibitors (NSMIs) that can interfere with viral entry or viral propagation is of special interest and is vital in managing already infected cases. SARS-CoV-2 infection is mediated by the binding of viral Spike proteins (S-protein) to human cells through a 2-step process, which involves Angiotensin Converting Enzyme-2 (ACE2) and Transmembrane Serine Protease (TMPRSS)-2. Therefore, the development of novel inhibitors of ACE2/TMPRSS2 is likely to be beneficial in combating SARS-CoV-2 infections. However, the usage of ACE-2 inhibitors to block the SARS-CoV-2 viral entry requires additional studies as there are conflicting findings and severe health complications reported for these inhibitors in patients. Hence, the current interest is shifted toward the development of NSMIs, which includes natural antiviral phytochemicals and Nrf-2 activators to manage a SARS-CoV-2 infection. It is imperative to investigate the efficacy of existing antiviral phytochemicals and Nrf-2 activators to mitigate the SARS-CoV-2-mediated oxidative stress. Therefore, in this review, we have reviewed structural features of SARS-CoV-2 with special emphasis on key molecular targets and their known modulators that can be considered for the development of NSMIs.

Traditional Chinese Medicine in Treating Influenza: From Basic Science to Clinical Applications

Influenza infection is a highly contagious, acute febrile respiratory disease caused by the influenza virus. Traditional Chinese Medicine (TCM) has dominated plenty of theoretical and practical approaches in the treatment of influenza. It is, therefore, important to highlight the effects of TCM in the clinical treatment of influenza and their impact on inhibiting the growth of this virus in laboratory experiments. We scrutinized existing evidence on whether TCM is effective in clinical applications. Moreover, we described the potential mechanisms of TCM against the influenza virus. Our findings provide analytical evidence that supports the effectiveness of TCM in treating influenza infections as well as their mechanisms against this virus.

Traditional Herbal Medicine for the Prevention and Treatment of Cold and Flu in the Autumn of 2020, Overlapped With COVID-19

Many herbs and plants included in several traditional systems have promising bioactive compounds for modern drug therapy. The second round of COVID-19 cases will be accompanied by the spread of seasonal influenza in the fall. The combination of the influenza season and the second wave of COVID-19 may lead to more confusion and put more pressure on public health systems. A literature survey was accomplished using multiple databases including PubMed, Science Direct, ISI web of knowledge, and Google Scholar. The most important antiviral herbs for cold and flu are Thymus vulgaris, honeysuckle flowers, Andrographis, yarrow, peppermint leaf and oil, and Calendula. The most important expectorant herbs for flu and cold are tulsi, snake root, licorice root, clove, slippery elm root, marshmallow osha root, and sage leaf. Immunostimulant herbs for these 2 diseases are Echinacea root, Eucalyptus, garlic, ginseng, marshmallow, slippery elm, Isatisroot, Usnea lichen, myrrh resin, and ginger root. In this mini-review, we mention the key role of some of the most important herbal plants and prescriptions against influenza and cold on the basis of traditional Asian medicine.

COVID-19 Drug Treatment in China

Purpose of Review

An unprecedented outbreak of the novel coronavirus in China (COVID-19) occurred in December 2019, and then engulfed the entire world, presenting a significant and urgent threat to global health. Many research institutes have been involved in the development of drugs and vaccines against COVID-19.

Recent Findings

At present, the strategy of new use of old drugs is mainly used to screen candidate drugs against the novel coronavirus (later termed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)) and inhibit excessive immune response. Related research has made great progress.

Summary

In this review, we summarize the drugs used for COVID-19 treatment in China based on the emerging basic and clinical data. It is hoped that this review will be useful to provide guidance for the prevention, treatment, and control of COVID-19.

Discovery of Multitarget-Directed Ligands Against Influenza A Virus From Compound Yizhihao Through a Predictive System for Compound-Protein Interactions

Influenza A virus (IAV) is a threat to public health due to its high mutation rate and resistance to existing drugs. In this investigation, 15 targets selected from an influenza virus–host interaction network were successfully constructed as a multitarget virtual screening system for new drug discovery against IAV using Naïve Bayesian, recursive partitioning, and CDOCKER methods. The predictive accuracies of the models were evaluated using training sets and test sets. The system was then used to predict active constituents of Compound Yizhihao (CYZH), a Chinese medicinal compound used to treat influenza. Twenty-eight compounds with multitarget activities were selected for subsequent in vitro evaluation. Of the four compounds predicted to be active on neuraminidase (NA), chlorogenic acid, and orientin showed inhibitory activity in vitro. Linarin, sinensetin, cedar acid, isoliquiritigenin, sinigrin, luteolin, chlorogenic acid, orientin, epigoitrin, and rupestonic acid exhibited significant effects on TNF-α expression, which is almost consistent with predicted results. Results from a cytopathic effect (CPE) reduction assay revealed acacetin, indirubin, tryptanthrin, quercetin, luteolin, emodin, and apigenin had protective effects against wild-type strains of IAV. Quercetin, luteolin, and apigenin had good efficacy against resistant IAV strains in CPE reduction assays. Finally, with the aid of Gene Ontology biological process analysis, the potential mechanisms of CYZH action were revealed. In conclusion, a compound-protein interaction-prediction system was an efficient tool for the discovery of novel compounds against influenza, and the findings from CYZH provide important information for its usage and development.

Santin inhibits influenza A virus replication through regulating MAPKs and NF-κB pathways

Influenza A virus (IAV) causes high morbidity and significant mortality worldwide. Given the limitations of existing vaccination and antiviral drugs, it is urgent to develop new anti-influenza drugs. Flavonoids are natural polyphenolic compounds with broad applications to treatments for influenza infection. In this study, we demonstrated that santin, a flavonoid compound, showed anti-influenza activity in MDCK and THP-1 cells. Mechanistic studies revealed that santin depressed the phosphorylation of p38 MAPK, JNK/SAPK, ERK, and NF-κB factor and subsequently attenuated the expression of inflammatory cytokines in IAV-infected cells. Thus, santin is a potential candidate for the future development of anti-IAV drugs.

Antiviral Activity Against Infectious Bronchitis Virus and Bioactive Components of Hypericum perforatum L

Hypericum perforatum L., also known as Saint John’s Wort, has been well studied for its chemical composition and pharmacological activity. In this study, the antiviral activities of H. perforatum on infectious bronchitis virus (IBV) were evaluated in vitro and in vivo for the first time. The results of in vitro experiments confirmed that the antiviral component of H. perforatum was ethyl acetate extraction section (HPE), and results showed that treatment with HPE significantly reduced the relative messenger ribonucleic acid (mRNA) expression and virus titer of IBV, and reduced positive green immunofluorescence signal of IBV in chicken embryo kidney (CEK) cells. HPE treatment at doses of 480–120 mg/kg for 5 days, reduced IBV induced injury in the trachea and kidney, moreover, reduced the mRNA expression level of IBV in the trachea and kidney in vivo. The mRNA expression levels of IL-6, tumor necrosis factor alpha (TNF-α), and nuclear factor kappa beta (NF-κB) significantly decreased, but melanoma differentiation-associated protein 5 (MDA5), mitochondrial antiviral signaling gene, interferon alpha (IFN-α), and interferon beta (IFN-β) mRNA levels significantly increased in vitro and in vivo. Our findings demonstrated that HPE had significant anti-IBV effects in vitro and in vivo, respectively. In addition, it is possible owing to up-regulate mRNA expression of type I interferon through the MDA5 signaling pathway and down-regulate mRNA expression of IL-6 and TNF-α via the NF-κB signaling pathway. Moreover, the mainly active compositions of HPE analyzed by high-performance liquid chromatography/electrospray ionization–mass spectroscopy (ESI-MS) are hyperoside, quercitrin, quercetin, pseudohypericin, and hypericin, and a combination of these compounds could mediate the antiviral activities. This might accelerate our understanding of the antiviral effect of H. perforatum and provide new insights into the development of effective therapeutic strategies.

Quercetin is the Active Component of Yang-Yin-Qing-Fei-Tang to Induce Apoptosis in Non-Small Cell Lung Cancer

Yang-Yin-Qing-Fei-Tang (YYQFT) is a well-known traditional Chinese medicine used in the treatment of chronic obstructive pulmonary emphysema, bronchitis, cytomegaloviral pneumonia, but the mechanisms of the medicine are not clear. This study aimed to identify the active components of YYQFT and elucidate the underlying mechanism on non-small cell lung cancer. First, YYQFT was extracted with different solvents, and then the most effective extract was determined by assessing their effects on non-small cell lung cancer cell growth. Second, several active compounds from YYQFT were identified, and quercetin was the one of the important active ingredients. Subsequently, the in vivo antitumor activity of quercetin was confirmed in a lung cancer xenograft model in mice. 200 μ g/mL quercetin significantly reduced tumor volume without affecting body weight of the mice. Furthermore, induction of apoptosis by quercetin was detected in tumor tissues treated with quercetin. Multiple apoptosis related genes including p53, Bax and Fas were upregulated by quercetin in tumor tissue and the ratio of Bax/Bcl-2 was increased accordingly. Our results demonstrated that quercetin, as the main effective component of the YYQFT, has potent inhibitory activity on non-small cell lung cancer by regulating the ratio of Bax/Bcl-2.

Silibinin ameliorates hepatic lipid accumulation and oxidative stress in mice with non-alcoholic steatohepatitis by regulating CFLAR-JNK pathway

Non-alcoholic steatohepatitis (NASH) is a chronic metabolic syndrome and the CFLAR-JNK pathway can reverse the process of NASH. Although silibinin is used for the treatment of NASH in clinical, its effect on CFLAR-JNK pathway in NASH remains unclear. This study aimed to investigate the effect of silibinin on CFLAR-JNK pathway in NASH models both in vivo and in vitro. The in vivo study was performed using male C57BL/6 mice fed with methionine- choline-deficient diet and simultaneously treated with silibinin for 6 weeks. The in vitro study was performed by using mouse NCTC-1469 cells which were respectively pretreated with oleic acid plus palmitic acid, and adenovirus-down Cflar for 24 h, then treated with silibinin for 24 h. After the drug treatment, the key indicators involved in CFLAR-JNK pathway including hepatic injury, lipid metabolism and oxidative stress were determined. Silibinin significantly activated CFLAR and inhibited the phosphorylation of JNK, up-regulated the mRNA expression of Pparα, Fabp5, Cpt1α, Acox, Scd-1, Gpat and Mttp, reduced the activities of serum ALT and AST and the contents of hepatic TG, TC and MDA, increased the expression of NRF2 and the activities of CAT, GSH-Px and HO-1, and decreased the activities and expression of CYP2E1 and CYP4A in vivo. These effects were confirmed by the in vitro experiments. Silibinin prevented NASH by regulating CFLAR-JNK pathway, and thereby on one hand promoting the β-oxidation and efflux of fatty acids in liver to relieve lipid accumulation, and on the other hand inducing antioxidase activity (CAT, GSH-Px and HO-1) and inhibiting pro-oxidase activity (CYP2E1 and CYP4A) to relieve oxidative stress.

Dynamics between infectious diseases with two susceptibility conditions: A mathematical model

This paper presents a novel epidemiological transmission model of a population affected by two different susceptible-infected-susceptible infectious diseases. For each disease, individuals fall into one of the two susceptibility conditions in which one of the diseases has the highest occurrence level. This model is unique in assuming that: (a) if an individual is infected by one disease, their susceptibility to the other disease is increased; (b) when an individual recovers from a disease they become less susceptible to it, i.e. they acquire partial immunity. The model captures these two assumptions by utilizing a coupled system of differential equations. Dynamic analysis of the system is based on basic reproductive number theory, and pattern visualization was performed using numerical simulation.

Therapeutic Modulation of Virus-Induced Oxidative Stress via the Nrf2-Dependent Antioxidative Pathway

Virus-induced oxidative stress plays a critical role in the viral life cycle as well as the pathogenesis of viral diseases. In response to reactive oxygen species (ROS) generation by a virus, a host cell activates an antioxidative defense system for its own protection. Particularly, a nuclear factor erythroid 2p45-related factor 2 (Nrf2) pathway works in a front-line for cytoprotection and detoxification. Recently, a series of studies suggested that a group of clinically relevant viruses have the capacity for positive and negative regulations of the Nrf2 pathway. This virus-induced modulation of the host antioxidative response turned out to be a crucial determinant for the progression of several viral diseases. In this review, virus-specific examples of positive and negative modulations of the Nrf2 pathway will be summarized first. Then a number of successful genetic and pharmacological manipulations of the Nrf2 pathway for suppression of the viral replication and the pathogenesis-associated oxidative damage will be discussed later. Understanding of the interplay between virus-induced oxidative stress and antioxidative host response will aid in the discovery of potential antiviral supplements for better management of viral diseases.