Arbidol increases the survival rate by mitigating inflammation in suckling mice infected with human coronavirus OC43 virus.

Human coronavirus OC43 (HCoV-OC43) often causes common cold and is able to neuroinvasive, but it can also induce lower respiratory tract infections (LRTI) especially in children and the elderly adults with underlying diseases. HCoV-OC43 infections currently have no approved antiviral treatment. Arbidol (ARB) is a broad-spectrum antiviral and is an antiviral medication for the treatment of influenza used in Russia and China. Due to its multiple mechanisms of action, such as inhibition of viral fusion and entry, immunomodulation, and modulation of host cell signaling pathways, ARB has the potential to be an effective treatment option for viral infections. Therefore, the study aims to investigate the activities of ARB against HCoV-OC43 infections. Suckling mice were infected with HCoV-OC43 and treated with ARB (50, 25 and 12.5 mg/kg/d) by gavage once daily for 4 days. the survival rates and body weight were recorded, the viral titer was measured by real-time quantitative polymerase chain reaction, cytokine levels were measured by Bio-Plex assays. Histopathological changes of the lungs and brain were analyzed. Our results show ARB increased the survival rate, reduced viral copy numbers in the lung, mitigated pro-inflammatory cytokine production, and improved brain and lung histopathology significantly without any significant toxicity or side effects in vivo. Our results suggest ARB could be a promising approach for the prevention and treatment of HCoV-OC43 while further studies are needed to address these possibilities and the underlying mechanism.

Coinfection with influenza virus and non-typeable Haemophilus influenzae aggregates inflammatory lung injury and alters gut microbiota in COPD mice.

Background: Acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is associated with high mortality rates. Viral and bacterial coinfection is the primary cause of AECOPD. How coinfection with these microbes influences host inflammatory response and the gut microbiota composition is not entirely understood. Methods: We developed a mouse model of AECOPD by cigarette smoke exposure and sequential infection with influenza H1N1 virus and non-typeable Haemophilus influenzae (NTHi). Viral and bacterial titer was determined using MDCK cells and chocolate agar plates, respectively. The levels of cytokines, adhesion molecules, and inflammatory cells in the lungs were measured using Bio-Plex and flow cytometry assays. Gut microbiota was analyzed using 16S rRNA gene sequencing. Correlations between cytokines and gut microbiota were determined using Spearman's rank correlation coefficient test. Results: Coinfection with H1N1 and NTHi resulted in more severe lung injury, higher mortality, declined lung function in COPD mice. H1N1 enhanced NTHi growth in the lungs, but NTHi had no effect on H1N1. In addition, coinfection increased the levels of cytokines and adhesion molecules, as well as immune cells including total and M1 macrophages, neutrophils, monocytes, NK cells, and CD4 + T cells. In contrast, alveolar macrophages were depleted. Furthermore, coinfection caused a decline in the diversity of gut bacteria. Muribaculaceae, Lactobacillus, Akkermansia, Lachnospiraceae, and Rikenella were further found to be negatively correlated with cytokine levels, whereas Bacteroides was positively correlated. Conclusion: Coinfection with H1N1 and NTHi causes a deterioration in COPD mice due to increased lung inflammation, which is correlated with dysbiosis of the gut microbiota.

Containment of SARS-CoV-2 Delta strain in Guangzhou, China by quarantine and social distancing: a modelling study.

China detected the first case of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection with Delta variant in May 2021. We assessed control strategies against this variant of concern. We constructed a robust transmission model to assess the effectiveness of interventions against the Delta variant in Guangzhou with initial quarantine/isolation, followed by social distancing. We also assessed the effectiveness of alternative strategies and that against potentially more infectious variants. The effective reproduction number (Rt) fell below 1 when the average daily number of close contacts was reduced to ≤ 7 and quarantine/isolation was implemented on average at the same day of symptom onset in Guangzhou. Simulations showed that the outbreak could still be contained when quarantine is implemented on average 1 day after symptom onset while the average daily number of close contacts was reduced to ≤ 9 per person one week after the outbreak's beginning. Early quarantine and reduction of close contacts were found to be important for containment of the outbreaks. Early implementation of quarantine/isolation along with social distancing measures could effectively suppress spread of the Delta and more infectious variants.

A Mouse-Adapted Model of HCoV-OC43 and Its Usage to the Evaluation of Antiviral Drugs.

The human coronavirus OC43 (HCoV-OC43) is one of the most common causes of common cold but can lead to fatal pneumonia in children and elderly. However, the available animal models of HCoV-OC43 did not show respiratory symptoms that are insufficient to assist in screening antiviral agents for respiratory diseases. In this study, we adapted the HCoV-OC43 VR-1558 strain by serial passage in suckling C57BL/6 mice and the resulting mouse-adapted virus at passage 9 (P9) contained 8 coding mutations in polyprotein 1ab, spike (S) protein, and nucleocapsid (N) protein. Pups infected with the P9 virus significantly lost body weight and died within 5 dpi. In cerebral and pulmonary tissues, the P9 virus replication induced the production of G-CSF, IFN-γ, IL-6, CXCL1, MCP-1, MIP-1α, RANTES, IP-10, MIP-1ß, and TNF-α, as well as pathological alterations including reduction of neuronal cells and typical symptoms of viral pneumonia. We found that the treatment of arbidol hydrochloride (ARB) or Qingwenjiere Mixture (QJM) efficiently improved the symptoms and decreased n gene expression, inflammatory response, and pathological changes. Furthermore, treating with QJM or ARB raised the P9-infected mice's survival rate within a 15 day observation period. These findings suggested that the new mouse-adapted HCoV-OC43 model is applicable and reproducible for antiviral studies of HCoV-OC43.

Broad antiviral and anti-inflammatory activity of Qingwenjiere mixture against SARS-CoV-2 and other human coronavirus infections.

BACKGROUND: Qingwenjiere Mixture (QJM) is a traditional Chinese medicine (TCM) that has been shown to have remarkable clinical efficacy against COVID-19. However, little is known about the antiviral and anti-inflammatory activities of QJM against a wider range of human coronavirus (HCoV) strains. PURPOSE: The study aims to investigate the antiviral and anti-inflammatory activities of QJM, as well as the underlying mechanisms against HCoV infections. METHODS: The chemical compositions from QJM were analyzed by LC-MS. The inhibitory effect of QJM on infections of HCoV-OC43, HCoV-229E, HCoV-NL63, and SARS-CoV-2 was evaluated in HRT-18 cells, Huh7 cells, LLC-MK2 cells, and Vero-E6 cells, respectively, by using cytopathic effect (CPE) inhibition assay or RT-qPCR detection of viral n, s, or RdRp/Hel genes. The expression of pro-inflammatory cytokines induced by HCoV-OC43, HCoV-229E, and SARS-CoV-2, as well as the host ace2 gene was also determined by RT-qPCR assay. Furthermore, the expression of key molecules in the NF-κB/MAPKs signaling pathways was determined by western blot. RESULTS: In alcohol-extraction groups of QJM and reference decoction pieces, 53 similar ion peaks were identified, the majority of which were phenylpropanoids, iridoids, and flavonoids. In addition, QJM reduced CPE caused by HCoVs and the expression of viral n genes or N protein. Pretreatment with QJM also exerted inhibitory effect on viral n gene expression. QJM also inhibited the expression of RdRp/Hel and s genes of SARS-CoV-2, as well as the host ace2 gene. Besides, QJM markedly reduced virus-induced mRNA expression of a panel of pro-inflammatory cytokines, such as IL-6, CXCL-8/IL-8, CXCL-10/IP-10, CCL-5/RANTES, TNF-α, IFN-α, CCL-2/MCP-1, CXCL-9/MIG, and IL1-α. We further showed that QJM inhibited the phosphorylation of NF-κB p65, and JNK, ERK 1/2, and p38 MAPKs in HCoV-OC43-infected HRT-18 cells. CONCLUSIONS: QJM has broad antiviral and anti-inflammatory activity against both common and newly emerged HCoVs possibly by inhibiting the activation of key components in NF-κB/MAPKs signaling pathway. QJM also has a prevention effect against HCoV infections and inhibits the host receptor required for virus entry. These results indicate that QJM may have the therapeutic potential in the treatment of diseases caused by a broad range of HCoVs.

ß-sitosterol ameliorates influenza A virus-induced proinflammatory response and acute lung injury in mice by disrupting the cross-talk between RIG-I and IFN/STAT signaling.

ß-Sitosterol (24-ethyl-5-cholestene-3-ol) is a common phytosterol Chinese medical plants that has been shown to possess antioxidant and anti-inflammatory activity. In this study we investigated the effects of ß-sitosterol on influenza virus-induced inflammation and acute lung injury and the molecular mechanisms. We demonstrate that ß-sitosterol (150-450 µg/mL) dose-dependently suppresses inflammatory response through NF-κB and p38 mitogen-activated protein kinase (MAPK) signaling in influenza A virus (IAV)-infected cells, which was accompanied by decreased induction of interferons (IFNs) (including Type I and III IFN). Furthermore, we revealed that the anti-inflammatory effect of ß-sitosterol resulted from its inhibitory effect on retinoic acid-inducible gene I (RIG-I) signaling, led to decreased STAT1 signaling, thus affecting the transcriptional activity of ISGF3 (interferon-stimulated gene factor 3) complexes and resulting in abrogation of the IAV-induced proinflammatory amplification effect in IFN-sensitized cells. Moreover, ß-sitosterol treatment attenuated RIG-I-mediated apoptotic injury of alveolar epithelial cells (AEC) via downregulation of pro-apoptotic factors. In a mouse model of influenza, pre-administration of ß-sitosterol (50, 200 mg·kg-1·d-1, i.g., for 2 days) dose-dependently ameliorated IAV-mediated recruitment of pathogenic cytotoxic T cells and immune dysregulation. In addition, pre-administration of ß-sitosterol protected mice from lethal IAV infection. Our data suggest that ß-sitosterol blocks the immune response mediated by RIG-I signaling and deleterious IFN production, providing a potential benefit for the treatment of influenza.

Sinensetin suppresses influenza a virus-triggered inflammation through inhibition of NF-κB and MAPKs signalings.

BACKGROUND: Human respiratory system infected with influenza A virus (IAV) elicited a robust pro-inflammatory response that resulted in severe illness and even death. Currently, limited immunomodulator is available to counteract IAV-associated pneumonia in the clinic. Sinensetin, a polymethoxylated flavone with five methoxy groups, has been found to possess anti-agiogenesis, anti-inflammatory and anti-diabetic activities. However, the effects of sinensetin on IAV-triggered pro-inflammatory response remain unclear. In the present study, the anti-inflammatory effects and corresponding possible mechanism of sinensetin in IAV-infected A549 cells were subjected to investigations. METHODS: The cytotoxic effects of sinensetin towards A549 cells was detected by MTT and LDH assays. The antiviral activity of sinensetin against influenza A virus was assayed in A549 cells with an engineered replication-competent influenza A virus carrying Gaussia luciferase reporter gene infection. The effect of sinensetin on influenza A virus-triggered inflammatory reaction was determined by qRT-PCR, Luminex assays, ELISA and Western blot. RESULTS: Our results showed that sinensetin did not exhibit antiviral activity against A/PR/8/34 (H1N1). Meanwhile, sinensetin treatment significantly decreased IAV-induced expression of pro-inflammatory mediators at mRNA and protein levels, including IL-6, TNF-α, IP-10, IL-8 and MCP-1. Additionally, levels of cyclooxygenase (COX)-2 and the downstream product prostaglandin E2 (PGE2) up-regulated by IAV infection were dramatically suppressed by sinensetin. The mechanistic investigation revealed that sinensetin treatment suppressed the NF-κB transcriptional activity using the NF-κB reporter stable HEK293 cell line stimulated with TNF-α (20 ng/mL) or influenza H1N1 virus. Furthermore, sinensetin abrogated influenza H1N1 virus-induced activation of NF-κB, ERK1/2 MAPK and p38 MAPK signalings. CONCLUSION: Collectively, our results indicated that sinensetin has potential capacity to attenuate IAV-triggered pro-inflammatory response via inactivation of NF-κB, ERK1/2 MAPK and p38 MAPK signalings, which implied that sinensetin may be a promising candidate drug for influenza H1N1 virus infection therapeutics.

Efficacy of indoor air purification in the treatment of Artemisia pollen-allergic rhinitis: A randomised, double-blind, clinical controlled trial.

OBJECTIVES: To evaluate the clinical efficacy of a high-efficiency air purifier in patients with allergic rhinitis. DESIGN: We conducted a randomised, double-blind, clinical controlled trial with active and inactive versions of an air purifier. Our study included patients with allergic rhinitis who were sensitive to Artemisia pollen and treatment of the indoor environment using air filtration at night. We evaluated the clinical efficacy of indoor air filtration during the Artemisia pollen scattering season in Yulin City in Shanxi Province, China. SETTING: The First Hospital of Yulin (Yulin City, Shanxi Province, China). PARTICIPANTS: A total of 90 patients with allergic rhinitis who were sensitive to allergens of Artemisia pollen were randomly assigned to one of two groups in equal numbers. MAIN OUTCOME MEASURES: The primary outcome measure was the difference in visual analogue scale scores from baseline. Secondary outcomes were changes from baseline in nasal symptoms, allergy symptom scores, responses to the Rhinoconjunctivitis Quality of Life Questionnaire, Epworth Sleepiness Scale scores and tolerability scores for the air purifier. RESULTS: Based on the allergy symptom score, we found significant differences in rhinitis symptoms between the groups who used the active versus the inactive air purifier. CONCLUSIONS: The results of our investigation demonstrated the health benefits of particle filtration.

Ergosterol peroxide suppresses influenza A virus-induced pro-inflammatory response and apoptosis by blocking RIG-I signaling.

Ergosterol peroxide has been shown to exhibit anti-tumor, antioxidant and anti-bacterial properties. However, the effects of ergosterol peroxide isolated from the herbal Baphicacanthus cusia root on influenza virus infection remain poorly understood. In the present study, ergosterol peroxide (compound 22) was obtained from the B. cusia root and subjected to investigation regarding its immunoregulatory effect on influenza A virus (IAV)-induced inflammation in A549 human alveolar epithelial cells. The structure of compound 22 isolated from B. cusia root. was elucidated by NMR analyses. Structure determination showed that the chemical structure of compound 22 closely resembles that of ergosterol peroxide. We observed that ergosterol peroxide treatment significantly suppressed IAV-induced upregulation of RIG-I expression. Additionally, ergosterol peroxide inhibited the activation of RIG-I downstream signaling pathways, including p38 MAP kinase and NF-κB, which ultimately resulted in the reduced production of an array of pro-inflammatory mediators and interferons (IFN-ß and IFN-λ1). Interestingly, inhibitory effects of ergosterol peroxide on the expression of IFNs did not affect the expression of antiviral effectors or enhance viral replication. On the other hand, ergosterol peroxide effectively abolished the amplified production of pro-inflammatory mediators in cells pretreated with IFN-ß (500 ng/ml) prior to IAV infection. Moreover, Annexin V and Hoechst 33258 staining revealed that increased apoptosis of IAV-infected cells was reversed by the presence of ergosterol peroxide. Our findings suggest that ergosterol peroxide from the B. cusia root suppressed IAV-associated inflammation and apoptosis via blocking RIG-I signaling, which may serve as a supplementary approach to the treatment of influenza.

(+)­pinoresinol­O­ß­D­glucopyranoside from Eucommia ulmoides Oliver and its anti­inflammatory and antiviral effects against influenza A (H1N1) virus infection.

Eucommia ulmoides Oliver (Du-Zhong) is an ancient Chinese herbal remedy used for the treatment of various diseases. To date, the effects of its constituent lignans on influenza viruses remain to be elucidated. In the present study, a lignan glycoside was isolated and purified from Eucommia ulmoides Oliver. Its structures were identified via extensive spectroscopic analysis, and its antiviral and anti­inflammatory activities, specifically against influenza viruses, were determined via a cytopathic effect (CPE) assay, plaque­reduction assays, a progeny virus yield reduction assay, reverse transcription­quantitative polymerase chain reaction analysis and a Luminex assay. Additionally, western blot analysis was performed to investigate the underlying mechanisms of its effects against influenza viruses. The chemical and spectroscopic methods determined the structure of lignan glycoside to be (+)­pinoresinol­O­ß­D­glucopyranoside. The CPE assay showed that (+)­pinoresinol­O­ß­D­glucopyranoside exerted inhibitory activities with 50% inhibition concentration values of 408.81±5.24 and 176.24±4.41 µg/ml against the influenza A/PR/8/34 (H1N1) and A/Guangzhou/GIRD07/09 (H1N1) strains, respectively. Its antiviral properties were confirmed by plaque reduction and progeny virus yield reduction assays. Additional mechanistic analyses indicated that the anti­H1N1 virus­induced effects of (+)­pinoresinol­O-ß­D-glucopyranoside were likely due to inactivation of the nuclear factor­κB, p38 mitogen­activated protein kinase and AKT signaling pathways. Furthermore, (+)­pinoresinol­O­ß­D­glucopyranoside exhibited pronounced inhibitory effects on the expression of influenza H1N1 virus­induced pro­inflammatory mediators, including tumor necrosis factor­α, interleukin (IL)­6, IL­8 and monocyte chemoattractant protein 1. The data obtained suggest that (+)­pinoresinol­O­ß­D-glucopyranoside may be a candidate drug for treating influenza H1N1 virus infection.

Efficacy of indoor air purification in treating Artemisia (mugwort) pollen allergic rhinitis: study protocol for a randomised controlled trial.

BACKGROUND: Allergic rhinitis (AR) is a worldwide health problem. Allergen avoidance is strongly recommended for AR patients. Air purification can reduce concentrations of particles in indoor air, including those of allergens. Air purifiers have been recommended by clinicians for AR patients, but few studies have focused on the removal of airborne allergens from home environments. Such studies have been limited by a lack of blinding, small samples, or a failure to measure allergen levels, disease activity, or a combination of these factors. This study investigates the efficacy of a high-efficiency air purifier in reducing disease activity in the homes of AR patients sensitive to the allergens produced by Artemisia (mugwort) pollen. METHODS: This is a randomized, double-blind, clinical controlled trial that will test active and inactive versions of an air purifier (Atmosphere®; Amway China). Sixty AR patients sensitive to the allergens produced by Artemisia pollen will be assigned randomly to two groups of equal numbers. All patients will undergo a 4-week treatment period and a 4-week observation period. Evaluation will be conducted at baseline (day 0) and on days 7, 14, 21, 28, and 56. The primary outcome measure will be the difference in visual analog scale scores from baseline. Secondary outcomes will be changes from baseline in nasal symptoms, allergy symptom scores, responses to the Rhinoconjunctivitis Quality of Life Questionnaire, Epworth Sleepiness Scale scores, and tolerability scores for the air purifier. Side effects of treatment will be recorded. DISCUSSION: Reducing exposure to allergens can reduce the risk of conditions such as AR. We hypothesise that AR patients sensitive to the allergens produced by Artemisia pollen will not suffer symptoms in a pollen-free environment. AR patients can remove pollen from their homes using air purifiers, decreasing the risk of symptoms. We expect that our study results will provide reliable evidence for determining the effects of air-purification therapy. TRIAL REGISTRATION: ChiCTR-INR-17012481 . (Retrospectively registered 26 August 2017).