Luciferase Reporter Systems in Investigating Interferon Antiviral Innate Immunity.

Luciferase reporter systems are commonly used in scientific research to investigate a variety of biological processes, including antiviral innate immunity. These systems employ the use of luciferase enzymes derived from organisms such as fireflies or renilla reniformis, which emit light upon reaction with a substrate. In the context of antiviral innate immunity, the luciferase reporter systems offer a noninvasive and highly sensitive approach for real-time monitoring of immune responses in vitro and in vivo, enabling researchers to delve into the intricate interactions and signaling pathways involved in host-virus dynamic interactions. Here, we describe the methods of the promoter-luciferase reporter and enhancer-luciferase reporter, which provide insights into the transcriptional and post-transcriptional regulation of antiviral innate immunity. Additionally, we outline the split-luciferase complementary reporter method, which was designed to explore protein-protein interactions associated with antiviral immunity. These methodologies offer invaluable knowledge regarding the molecular mechanisms underlying antiviral immune pathways and have the potential to support the development of effective antiviral therapies.

Epidemiological Study in Antiviral Innate Immunity.

This chapter summarizes the epidemiological study design of natural immune epidemiology studies based on recent COVID-19-related research. The epidemiological studies on antiviral innate immunity have mainly included randomized controlled trials (RCTs) and observational studies. Importantly, this chapter will discuss how to use these methodologies to answer an epidemiological question of natural immunity in the viral infection process based on previous studies. An observational case- or cohort-based study of antiviral innate immunity may support this theoretical hypothesis but is not appropriate for clinical practice or treatment. RCTs are the gold standard for epidemiological studies and occupy a greater role in the hierarchy of evidence.

An integrative pharmacology-based study on the efficacy and mechanism of essential oil of Chaihu Guizhi Decoction on influenza A virus induced pneumonia in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Chaihu Guizhi Decoction (CGD) has a long history of use in China for the treatment of influenza, which involves the use of a variety of aromatic herbs. Our previous studies have found that the contents of aromatic constituents in CGD affected the efficacy of treatment of influenza-infected mice, suggesting a clue that essential oil from CGD may play a relatively important role in ameliorating influenza induced pneumonia. AIM OF THE STUDY: To evaluate the anti-influenza potential of essential oil derived from Chaihu Guizhi Decoction (CGD-EO), to characterize and predict the key active components in CGD-EO, and to explore the mechanism of action of CGD-EO. MATERIALS AND METHODS: CGD-EO was obtained by steam distillation, and the components of the essential oil were characterized by gas chromatography-mass spectrometry (GC-MS) in conjunction with the retention index. The constituents absorbed into the blood of mice treated with CGD-EO were analyzed by headspace solid phase microextraction gas chromatography/mass spectrometry (HS-SPME-GC/MS). The potential anti-influenza active constituents and their possible action pathway were predicted by simulation using a network pharmacology approach. The protective effect of CGD-EO and its major components on H1N1/PR8-infected cells was determined using the CCK8 assay kit. Mice infected with influenza A virus H1N1/PR8 were administered different doses of CGD-EO orally and the body weights and lung weights were recorded. Mice with varying degrees of H1N1/PR8 infection were administered CGD-EO orally, and their daily weight, water consumption, and clinical indicators were recorded. Necropsies were conducted on days 3 and 5, during which lung weights were measured and lung tissues were preserved. Furthermore, the mRNA expression of the H1N1/PR8 virus and inflammatory factors in lung tissue was analyzed using RT-qPCR. RESULTS: (E)-cinnamaldehyde was the most abundant compound in the CGD-EO. The results of serum medicinal chemistry combined with network pharmacological analysis indicated that (E)-cinnamaldehyde and 3-phenyl-2-propenal may be potential active components of the CGD-EO anti-influenza, and may be involved in the NF-κB signalling pathway. In vitro studies have demonstrated that both CGD-EO and cinnamaldehyde exert a protective effect on MDCK cells infected with H1N1/PR8. In a 0.5 TCID50 H1N1/PR8-induced influenza model, mice treated with CGD-EO at a dose of 63.50 µg/kg exhibited a reduction in lung index, pathological lung lesions, and H1N1/PR8 viral gene levels. In addition, CGD-EO treatment was found to regulate the levels of inflammatory cytokines, including IL-6, TNF-α, and IFN-γ. Moreover, following three days of administration, an upregulation of NF-κB mRNA levels in mouse lung tissue was observed in response to CGD-EO treatment. CONCLUSIONS: The findings of our study indicate CGD-EO exerts a protective effect against H1N1-induced cytopathic lesions in vitro and is capable of alleviating H1N1-induced pneumonitis in mice. Moreover, it appears to be more efficacious in the treatment of mild symptoms of H1N1 infection. Studies have demonstrated that CGD-EO has antiviral potential to attenuate influenza-induced lung injury by modulating inflammatory cytokines and NF-κB signalling pathways during the early stages of influenza infection. It is possible that (E)-cinnamaldehyde is a potential active ingredient in the anti-influenza efficacy of CGD-EO.

Exploring the action mechanism and effective components of Yupingfeng powder on influenza based on computational system pharmacology and metabolomics.

ETHNOPHARMACOLOGICAL RELEVANCE: Yupingfeng powder (YPF) is a classic traditional Chinese medicine prescription with a long history of clinical application. However, there is a consensus on the clinical efficacy of YPF in the prevention and treatment of influenza, the underlying pharmacological mechanisms and functional substances have not been thoroughly investigated. AIM OF THE STUDY: This study aimed to elucidate the functional substances and potential mechanisms of YPF against influenza infections by integrating network analysis, metabolomics, computational system pharmacology, and in vitro experiments. MATERIALS AND METHODS: In this study, the active ingredients, related targets, and potential mechanisms of YPF against influenza were identified through network pharmacology and GEO database mining. Combined with metabolomics to corroborate the results of network pharmacology analysis and construct C-T-P-D-M network. Based on this, the key network motifs (KNM) with significance were predicted by system pharmacology algorithm. Finally, the key components as functional substances in the KNM were validated by the coverage of influenza-causing genes and functional pathways, and in vitro experiments. RESULTS: A total of 238 active components and 158 potential target genes intersecting with influenza infection differential genes were screened from YPF. KEGG enrichment analysis indicated that metabolism participated in YPF-provided prevention and treatment on influenza, and metabolomic results further corroborated the significance of the metabolic pathways intervened by YPF included pyruvate metabolism, Valine, leucine and isoleucine degradation, etc. The KNM prediction strategy was computed to include wogonin and isoimperaporin, a group of 48 potential functional components. This functional component group maintained a high degree of consistency with the corresponding C-T network in terms of the coverage of influenza pathogenic genes, and the coverage of functional pathways. Meanwhile, the in vitro results showed that wogonin and isoimperaporin had significant inhibitory effects on inflammation induced by influenza infection, confirming the reliability and accuracy of the KNM prediction strategy. CONCLUSION: YPF against influenza has multi-target and multi-pathway effects, and the underlying mechanisms may be related to metabolism. The pharmacodynamic effects of core components such as wogonin and isoimperaporin on influenza prevention and treatment were confirmed, which represent promising functional candidates for subsequent influenza prevention and treatment, and provide references for the pharmacological and mechanistic analyses of subsequent formulas.

Antiviral activity of Morus alba L. extract against pseudorabies virus.

ETHNOPHARMACOLOGICAL RELEVANCE: Morus alba L. are widely used as ethnomedicine and functional food in China, Japan, Korea and other Asian countries. Morus alba L. have a variety of pharmacological activity such as antiviral, antioxidation, anti-cholesterol, anticancer, hypoglycemia, and neuroprotection. Morus alba L. has demonstrated antiviral efficacy against influenza viruses, SARS-CoV-2 and so on, but its potential activity against pseudorabies virus (PRV) remains uncertain. AIM OF THE STUDY: This study endeavors to delve into the anti-pseudorabies virus (PRV) potential of the ethanol extract of Morus alba L. leaves (MLE), while simultaneously elucidating its underlying mechanism of action. MATERIALS AND METHODS: The anti-PRV activities of Morus alba L. extracts at different concentrations were evaluated by qPCR and immunoblotting. The inhibitory effects of MLE on PRV replication in three distinct treatment modes (pretreatment, co-treatment, and post-treatment) were detected by qPCR and indirect immunofluorescence assays. qPCR was used to investigate the effects of MLE on PRV attachment, entrance, and cytokine expression in PRV-infected cells. The chemical components in MLE were analyzed by UPLC-MS/MS. RESULTS: MLE significantly inhibits PRV replication and protein expression in a dose-dependent manner. MLE displays inhibitory effects against PRV at three different modes of treatment. The most significant inhibitory effect of MLE was observed when used in co-treatment mode, resulting in an inhibition rate of 99.42%. MLE inhibits PRV infection in the early stage. MLE inhibits PRV infection by affecting viral attachment and viral entry. Furthermore, MLE exerts its inhibition on PRV replication by mitigating the heightened expression of cytokines (TNF-α and IFN-α) triggered by PRV. Analysis of its chemical composition highlights phenolic acids and flavonoids as the principal constituents of MLE. CONCLUSION: The results illustrate that MLE effectively impedes PRV infection by suppressing viral adsorption and entry, while also curbing the expression of antiviral cytokines. Therefore, MLE may be a potential resource for creating new medications to treat human and animal PRV infections.

Diosmetin-7-O-ß-D-glucopyranoside from Pogostemonis Herba alleviated SARS-CoV-2-induced pneumonia by reshaping macrophage polarization and limiting viral replication.

ETHNOPHARMACOLOGICAL RELEVANCE: Viral pneumonia is the leading cause of death after SARS-CoV-2 infection. Despite effective at early stage, long-term treatment with glucocorticoids can lead to a variety of adverse effects and limited benefits. The Chinese traditional herb Pogostemonis Herba is the aerial part of Pogostemon Cablin (Blanco) Benth., which has potent antiviral, antibacterial, anti-inflammatory, and anticancer effects. It was used widely for treating various throat and respiratory diseases, including COVID-19, viral infection, cough, allergic asthma, acute lung injury and lung cancer. AIM OF THE STUDY: To investigate the antiviral and anti-inflammatory effects of chemical compounds from Pogostemonis Herba in SARS-CoV-2-infected hACE2-overexpressing mouse macrophage RAW264.7 cells and hACE2 transgenic mice. MATERIALS AND METHODS: The hACE2-overexpressing RAW264.7 cells were exposed with SARS-CoV-2. The cell viability was detected by CCK8 assay and cell apoptotic rate was by flow cytometric assay. The expressions of macrophage M1 phenotype markers (TNF-α and IL-6) and M2 markers (IL-10 and Arg-1) as well as the viral loads were detected by qPCR. The mice were inoculated intranasally with SARS-CoV-2 omicron variant to induce viral pneumonia. The levels of macrophages, neutrophils, and T cells in the lung tissues of infected mice were analyzed by full spectrum flow cytometry. The expressions of key proteins were detected by Western blot assay. RESULTS: Diosmetin-7-O-ß-D-glucopyranoside (DG) presented the strongest anti-SARS-CoV-2 activity. Intervention with DG at the concentrations of 0.625-2.5 µM not only reduced the viral replication, cell apoptosis, and the productions of inflammatory cytokines (IL-6 and TNF-α) in SARS-CoV-2-infected RAW264.7 cells, but also reversed macrophage polarity from M1 to M2 phenotype. Furthermore, treatment with DG (25-100 mg/kg) alleviated acute lung injury, and reduced macrophage infiltration in SARS-COV-2-infected mice. Mechanistically, DG inhibited SARS-COV-2 gene expression and HK3 translation via targeting YTHDF1, resulting in the inactivation of glycolysis-mediated NF-κB pathway. CONCLUSIONS: DG exerted the potent antiviral and anti-inflammatory activities. It reduced pneumonia in SARS-COV-2-infected mice via inhibiting the viral replication and accelerating M2 macrophage polarization via targeting YTHDF1, indicating its potential for COVID-19 treatment.

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.

Pulmonary delivery of silver nanoparticles prevents influenza infection by recruiting and activating lymphoid cells.

Silver nanoparticles (AgNPs) are a potential antiviral agent due to their ability to disrupt the viral particle or alter the virus metabolism inside the host cell. In vitro, AgNPs exhibit antiviral activity against the most common human respiratory viruses. However, their capacity to modulate immune responses during respiratory viral infections has yet to be explored. This study demonstrates that administering AgNPs directly into the lungs prior to infection can reduce viral loads and therefore virus-induced cytokines in mice infected with influenza virus or murine pneumonia virus. The prophylactic effect was diminished in mice with depleted lymphoid cells. We showed that AgNPs-treatment resulted in the recruitment and activation of lymphocytes in the lungs, particularly natural killer (NK) cells. Mechanistically, AgNPs enhanced the ability of alveolar macrophages to promote both NK cell migration and IFN-γ production. By contrast, following infection, in mice treated with AgNPs, NK cells exhibited decreased activation, indicating that these nanoparticles can regulate the potentially deleterious activation of these cells. Overall, the data suggest that AgNPs may possess prophylactic antiviral properties by recruiting and controlling the activation of lymphoid cells through interaction with alveolar macrophages.

Preventive and therapeutic effects of a super-multivalent sialylated filamentous bacteriophage against the influenza virus.

The resurgence of influenza viruses as a significant global threat emphasizes the urgent need for innovative antiviral strategies beyond existing treatments. Here, we present the development and evaluation of a novel super-multivalent sialyllactosylated filamentous phage, termed t-6SLPhage, as a potent entry blocker for influenza A viruses. Structural variations in sialyllactosyl ligands, including linkage type, valency, net charge, and spacer length, were systematically explored to identify optimal binding characteristics against target hemagglutinins and influenza viruses. The selected SLPhage equipped with optimal ligands, exhibited exceptional inhibitory potency in in vitro infection inhibition assays. Furthermore, in vivo studies demonstrated its efficacy as both a preventive and therapeutic intervention, even when administered post-exposure at 2 days post-infection, under 4 lethal dose 50% conditions. Remarkably, co-administration with oseltamivir revealed a synergistic effect, suggesting potential combination therapies to enhance efficacy and mitigate resistance. Our findings highlight the efficacy and safety of sialylated filamentous bacteriophages as promising influenza inhibitors. Moreover, the versatility of M13 phages for surface modifications offers avenues for further engineering to enhance therapeutic and preventive performance.

Broad-spectrum antiviral effect of MoringaA-loaded exosomes against IAV by mediating the GCN5-TFEB-autolysosome pathway.

Influenza virus-induced viral pneumonia is a major threat to human health, and specific therapeutic agents for viral pneumonia are still lacking. MoringaA (MA) is an anti-influenza virus active compound isolated from Moringa seeds, which can inhibit influenza virus by activating the TFEB-autophagic lysosomal pathway in host cells. In this study, we obtained exosomes from M2-type macrophages and encapsulated and delivered MA (MA-Exos), and we investigated the efficacy of MA-Exos in antiviral and viral pneumonia in vivo and in vitro, respectively. In addition, we provided insights into the mechanism by which MA-Exos regulates TFEB-lysosomal autophagy by RNA sequencing. The MA-Exos showed broad-spectrum inhibition of IAV, and significant promotion of the autophagic lysosomal pathway. Meanwhile, we found that GCN5 gene and protein were significantly down-regulated in IAV-infected cells after MA-Exos intervention, indicating its blocking the acetylation of TFEB by GCN5. In addition, MA-Exos also significantly promoted autophagy in lung tissue cells of mice with viral pneumonia. MA-Exos can inhibit and clear influenza virus by mediating the TFEB-autophagy lysosomal pathway by a mechanism related to the down-regulation of histone acetyltransferase GCN5. Our study provides a strategy for targeting MA-Exos for the treatment of viral pneumonia from both antiviral and virus-induced inflammation inhibition pathways.

Harnessing traditional Chinese medicine polysaccharides for combatting COVID-19.

With the global spread of COVID-19 posing ongoing challenges to public health systems, there is an ever-increasing demand for effective therapeutics that can mitigate both viral transmission and disease severity. This review surveys the landscape of polysaccharides derived from traditional Chinese medicine, acclaimed for their medicinal properties and potential to contribute to the COVID-19 response. We specifically focus on the capability of these polysaccharides to thwart SARS-CoV-2 entry into host cells, a pivotal step in the viral life cycle that informs transmission and pathogenicity. Moreover, we delve into the concept of trained immunity, an innate immune system feature that polysaccharides may potentiate, offering an avenue for a more moderated yet efficacious immune response against various pathogens, including SARS-CoV-2. Our comprehensive overview aims to bolster understanding of the possible integration of these substances within anti-COVID-19 measures, emphasizing the need for rigorous investigation into their potential applications and underlying mechanisms. The insights provided here strongly support ongoing investigations into the adjunctive use of polysaccharides in the management of COVID-19, with the anticipation that such findings could lead to a deeper appreciation and clearer elucidation of the antiviral potentials inherent in complex Chinese herbal remedies.

Hydroxyl radical-induced C1'-H abstraction reaction of different artificial nucleotides.

CONTEXT: Recently, a few antiviral drugs viz Molnupiravir (EIDD-1931), Favipiravir, Ribavirin, Sofosbuvir, Galidesivir, and Remdesivir are shown to be beneficial against COVID-19 disease. These drugs bind to the viral RNA single strand to inhibit the virus genome replication. Similarly, recently, some artificial nucleotides, such as P, J, B, X, Z, V, S, and K were proposed to behave as potent antiviral candidates. However, their activity in the presence of the most reactive hydroxyl (OH) radical is not yet known. Here, the possibility of RNA strand break due to the OH radical-induced C1'-hydrogen (H) abstraction reaction of the above molecules (except Remdesivir) is studied in detail by considering their nucleotide conformation. The results are compared with those of the natural RNA nucleotides (G, C, A, and U). Due to low Gibbs barrier-free energy and high exothermicity, all these nucleotides (except Remdesivir) are prone to OH radical-induced C1'-H abstraction reaction. As Remdesivir contains a C1'-CN bond, the OH radical substitution reactions at the CN and C1' sites would likely liberate the catalytically important CN group, thereby downgrading its activity. METHOD: Initially, the B3LYP-D3 dispersion-corrected density functional theory method and 6-31 + G* basis set were used to optimize all reactant, transition state, and product complexes in the implicit aqueous medium. Subsequently, the structures of these complexes were further optimized by using the ωB97X-D dispersion-corrected density functional theory method and cc-PVTZ basis set in the aqueous medium. The IEFPCM method was used to model the aqueous medium.

Recent advances in the design of small molecular drugs with acrylamides covalent warheads.

In the development of covalent inhibitors, acrylamides warhead is one of the most popular classes of covalent warheads. In recent years, researchers have made different structural modifications to acrylamides warheads, resulting in the creation of fluorinated acrylamide warheads and cyano acrylamide warheads. These new warheads exhibit superior selectivity, intracellular accumulation, and pharmacokinetic properties. Additionally, although ketoamide warheads have been applied in the design of covalent inhibitors for viral proteins, it has not received sufficient attention. Combined with the studies in kinase inhibitors and antiviral drugs, this review presents the structural features and the progression of acrylamides warheads, offering a perspective on future research and development in this field.

Tanomastat exerts multi-targeted inhibitory effects on viral capsid dissociation and RNA replication in human enteroviruses.

BACKGROUND: Global cyclical outbreaks of human enterovirus infections has positioned human enterovirus A71 (EV-A71) as a neurotropic virus of clinical importance. However, there remains a scarcity of internationally approved antivirals and vaccines. METHODS: In pursuit of repurposing drugs for combating human enteroviruses, we employed a comprehensive pharmacophore- and molecular docking-based virtual screen targeting EV-A71 capsid protein VP1-4, 3C protease, and 3D polymerase proteins. Among 15 shortlisted ligand candidates, we dissected the inhibitory mechanism of Tanomastat in cell-based studies and evaluated its in vivo efficacy in an EV-A71-infected murine model. FINDINGS: We demonstrated that Tanomastat exerts dose-dependent inhibition on EV-A71 replication, with comparable efficacy profiles in enterovirus species A, B, C, and D in vitro. Time-course studies suggested that Tanomastat predominantly disrupts early process(es) of the EV-A71 replication cycle. Mechanistically, live virus particle tracking and docking predictions revealed that Tanomastat specifically impedes viral capsid dissociation, potentially via VP1 hydrophobic pocket binding. Bypassing its inhibition on entry stages, we utilized EV-A71 replication-competent, 3Dpol replication-defective, and bicistronic IRES reporter replicons to show that Tanomastat also inhibits viral RNA replication, but not viral IRES translation. We further showed that orally administered Tanomastat achieved 85% protective therapeutic effect and alleviated clinical symptoms in EV-A71-infected neonatal mice. INTERPRETATION: Our study establishes Tanomastat as a broad-spectrum anti-enterovirus candidate with promising pre-clinical efficacy, warranting further testing for potential therapeutic application. FUNDING: MOE Tier 2 grants (MOE-T2EP30221-0005, R571-000-068-592, R571-000-076-515, R571-000-074-733) and A∗STARBiomedical Research Council (BMRC).

The efficacy and safety of ginger (Zingiber officinale) rhizome extract in outpatients with COVID-19: A randomized double-blind placebo-control clinical trial.

BACKGROUND: Ginger, a potent antiviral, anti-inflammatory, and antioxidant remedy, is a potential therapeutic option for COVID-19. However, there was not enough clinical evidence about ginger and COVID-19. We evaluated the efficacy and safety of ginger on clinical and paraclinical features in outpatients with COVID-19. METHODS: In this randomized controlled trial, the outpatients with confirmed COVID-19 were randomly assigned in a 1:1 ratio to receive ginger (1000 mg 3 times a day for 7 days) or placebo. The primary outcome was viral clearance after the end of the intervention. Oxygen saturation (SPO2), body temperature, respiratory rate (RR), hospital admission, and the incidence of adverse events were also assessed. RESULTS: A total of 84 patients (42 in the ginger and 42 in the control groups) were randomized. The viral clearance was not statistically improved in the ginger group (41.6%) compared to the placebo group (42.8%). The findings indicated that SPO2, body temperature, and RR had no significant difference between the groups at the end of the intervention. The imaging finding indicated pulmonary infiltrate significantly reduced on the 7th day of the intervention in the ginger group. The percentage of patients with SPO2 <96% in the ginger group decreased over the study compared to the placebo group. Moreover, the need for hospital admission and the incidence of adverse drug events were not different between the groups over the follow-up period. CONCLUSIONS: Ginger had no significant impact on the clinical and paraclinical parameters of patients. However, this intervention demonstrated a safe profile of adverse events and reduced pulmonary infiltrate. TRIAL REGISTRATION: The trial was registered as IRCT20200506047323N1.

PEG-SeNPs as therapeutic agents inhibiting apoptosis and inflammation of cells infected with H1N1 influenza A virus.

The rapid variation of influenza challenges vaccines and treatments, which makes an urgent task to develop the high-efficiency and low-toxicity new anti-influenza virus drugs. Selenium is one of the essential trace elements for the human body that possesses a good antiviral activity. In this study, we assessed anti-influenza A virus (H1N1) activity of polyethylene glycol (PEG)-modified gray selenium nanoparticles (PEG-SeNPs) on Madin-Darby Canine Kidney (MDCK) cells in vitro. CCK-8 assay showed that PEG-SeNPs had a protective effect on H1N1-infected MDCK cells. Moreover, PEG-SeNPs significantly reduced the mRNA level of H1N1. TUNEL-DAPI test showed that DNA damage reached a high level but effectively prevented after PEG-SeNPs treatment. Meanwhile, JC-1, Annexin V-FITC and cell cycle assay demonstrated the apoptosis induced by H1N1 was reduced greatly when treated with PEG-SeNPs. Furthermore, the downregulation of p-ATM, p-ATR and P53 protein, along with the upregualation of AKT protein indicated that PEG-SeNPs could inhibit H1N1-induced cell apoptosis through reactive oxygen species (ROS)-mediated related signaling pathways. Finally, Cytokine detection demonstrated PEG-SeNPs inhibited the production of pro-inflammatory factors after infection, including IL-1ß, IL-5, IL-6, and TNF-α. To sum up, PEG-SeNPs might become a new potential anti-H1N1 influenza virus drug due to its antiviral and anti-inflammatory activity.