Sulforaphane inhibits the expression of interleukin-6 and interleukin-8 induced in bronchial epithelial IB3-1 cells by exposure to the SARS-CoV-2 Spike protein.

BACKGROUND: A key clinical feature of COVID-19 is a deep inflammatory state known as "cytokine storm" and characterized by high expression of several cytokines, chemokines and growth factors, including IL-6 and IL-8. A direct consequence of this inflammatory state in the lungs is the Acute Respiratory Distress Syndrome (ARDS), frequently observed in severe COVID-19 patients. The "cytokine storm" is associated with severe forms of COVID-19 and poor prognosis for COVID-19 patients. Sulforaphane (SFN), one of the main components of Brassica oleraceae L. (Brassicaceae or Cruciferae), is known to possess anti-inflammatory effects in tissues from several organs, among which joints, kidneys and lungs. PURPOSE: The objective of the present study was to determine whether SFN is able to inhibit IL-6 and IL-8, two key molecules involved in the COVID-19 "cytokine storm". METHODS: The effects of SFN were studied in vitro on bronchial epithelial IB3-1 cells exposed to the SARS-CoV-2 Spike protein (S-protein). The anti-inflammatory activity of SFN on IL-6 and IL-8 expression has been evaluated by RT-qPCR and Bio-Plex analysis. RESULTS: In our study SFN inhibits, in cultured IB3-1 bronchial cells, the gene expression of IL-6 and IL-8 induced by the S-protein of SARS-CoV-2. This represents the proof-of-principle that SFN may modulate the release of some key proteins of the COVID-19 "cytokine storm". CONCLUSION: The control of the cytokine storm is one of the major issues in the management of COVID-19 patients. Our study suggests that SFN can be employed in protocols useful to control hyperinflammatory state associated with SARS-CoV-2 infection.

Unique synergistic antiviral effects of Shufeng Jiedu Capsule and oseltamivir in influenza A viral-induced acute exacerbation of chronic obstructive pulmonary disease.

BACKGROUND: The aim of the present study was to investigate the synergistic effects and interactive mechanisms of Shufeng Jiedu Capsule (SFJDC) combined with oseltamivir in the treatment of acute exacerbation of chronic obstructive pulmonary disease (AECOPD) induced by the influenza A virus (IAV). METHODS: The extraction of SFJDC was analyzed by UHPLC/ESI Q-Orbitrap Mass Spectrometry. Human bronchial epithelial cells were isolated from COPD (DHBE) bronchial tissues, co-cultured with IAV for 24 h, and were subsequently treated with SFJDC and/or oseltamivir. Cell viability was detected by MTT assay. A rat model of COPD with IAV infection was established and treated with SFJDC and/or oseltamivir. Interleukin (IL)-1ß and IL-18 in serum and bronchoalveolar lavage fluid (BALF) were measured by ELISA. Additionally, mRNA and protein levels of NLRP3 inflammasome pathway were measured by quantitative real-time PCR and Western blotting, respectively. RESULTS: SFJDC and/or oseltamivir, at their optimal concentrations, had no significant cytotoxicity against DHBEs. The levels of NLRP3-inflammasome-associated components were significantly elevated after cells were inoculated with IAV, whereas the mRNA and protein levels of these components were significantly decreased after treatment with SFJDC and/or oseltamivir in vitro. Moreover, in vivo, the combination of SFJDC and oseltamivir improved survival rates, attenuated clinical symptoms, induced weight gain, alleviated lung damage, and significantly reduced IL-1ß and IL-18 levels in serum and BALF, as well as reduced the expression levels of NLRP3-associated components and viral titers in lung homogenates. CONCLUSION: SFJDC combined with oseltamivir treatment significantly attenuated IAV-induced airway inflammation and lung viral titers. Hence, our findings may provide a novel therapeutic strategy for IAV-induced respiratory infection.

Self-complementary and tyrosine-mutant rAAV vectors enhance transduction in cystic fibrosis bronchial epithelial cells.

Recombinant adeno-associated virus (rAAV) vector platforms have shown considerable therapeutic success in gene therapy for inherited disorders. In cystic fibrosis (CF), administration of first-generation rAAV2 was safe, but clinical benefits were not clearly demonstrated. Therefore, next-generation vectors that overcome rate-limiting steps in rAAV transduction are needed to obtain successful gene therapy for this devastating disease. In this study, we evaluated the effects of single-strand or self-complementary (sc) rAAV vectors containing single or multiple tyrosine-to-phenylalanine (Y-F) mutations in capsid surface-exposed residues on serotypes 2, 8 or 9. For this purpose, CF bronchial epithelial (CFBE) cells were transduced with rAAV vectors, and the transgene expression of enhanced green fluorescence protein (eGFP) was analyzed at different time points. The effects of vectors on the cell viability, host cell cycle and in association with co-adjuvant drugs that modulate intracellular vector trafficking were also investigated. Six rAAV vectors demonstrated greater percentage of eGFP+ cells compared to their counterparts at days 4, 7 and 10 post-transduction: rAAV2 Y(272,444,500,730)F, with 1.95-, 3.5- and 3.06-fold increases; rAAV2 Y(252,272,444,500,704,730)F, with 1.65-, 2.12-, and 2-fold increases; scrAAV2 WT, with 1.69-, 2.68-, and 2.32-fold increases; scrAAV8 Y773F, with 57-, 6.06-, and 7-fold increases; scrAAV9 WT, with 7.47-, 4.64-, and 3.66-fold increases; and scrAAV9 Y446F, with 8.39-, 4.62-, and 4.4-fold increases. At days 15, 20, and 30 post-transduction, these vectors still demonstrated higher transgene expression than transfected cells. Although the percentage of eGFP+ cells reduced during the time-course analysis, the delta mean fluorescence intensity increased. These vectors also led to increased percentage of cells in G1-phase without eliciting any cytotoxicity. Prior administration of bortezomib or genistein did not increase eGFP expression in cells transduced with either rAAV2 Y(272,444,500,730)F or rAAV2 Y(252,272,444,500,704,730)F. In conclusion, self-complementary and tyrosine capsid mutations on rAAV serotypes 2, 8, and 9 led to more efficient transduction than their counterparts in CFBE cells by overcoming the intracellular trafficking and second-strand DNA synthesis limitations.

GS-5806 Inhibits a Broad Range of Respiratory Syncytial Virus Clinical Isolates by Blocking the Virus-Cell Fusion Process.

Respiratory syncytial virus (RSV) is a leading cause of lower respiratory tract infections in infants and young children. In addition, RSV causes significant morbidity and mortality in hospitalized elderly and immunocompromised patients. Currently, only palivizumab, a monoclonal antibody against the RSV fusion (F) protein, and inhaled ribavirin are approved for the prophylactic and therapeutic treatment of RSV, respectively. Therefore, there is a clinical need for safe and effective therapeutic agents for RSV infections. GS-5806, discovered via chemical optimization of a hit from a high-throughput antiviral-screening campaign, selectively inhibits a diverse set of 75 RSV subtype A and B clinical isolates (mean 50% effective concentration [EC50] = 0.43 nM). The compound maintained potency in primary human airway epithelial cells and exhibited low cytotoxicity in human cell lines and primary cell cultures (selectivity > 23,000-fold). Time-of-addition and temperature shift studies demonstrated that GS-5806 does not block RSV attachment to cells but interferes with virus entry. Follow-up experiments showed potent inhibition of RSV F-mediated cell-to-cell fusion. RSV A and B variants resistant to GS-5806, due to mutations in F protein (RSV A, L138F or F140L/N517I, and RSV B, F488L or F488S), were isolated and showed cross-resistance to other RSV fusion inhibitors, such as VP-14637, but remained fully sensitive to palivizumab and ribavirin. In summary, GS-5806 is a potent and selective RSV fusion inhibitor with antiviral activity against a diverse set of RSV clinical isolates. The compound is currently under clinical investigation for the treatment of RSV infection in pediatric, immunocompromised, and elderly patients.

Effects of vitamin D on airway epithelial cell morphology and rhinovirus replication.

Vitamin D has been linked to reduced risk of viral respiratory illness. We hypothesized that vitamin D could directly reduce rhinovirus (RV) replication in airway epithelium. Primary human bronchial epithelial cells (hBEC) were treated with vitamin D, and RV replication and gene expression were evaluated by quantitative PCR. Cytokine/chemokine secretion was measured by ELISA, and transepithelial resistance (TER) was determined using a voltohmmeter. Morphology was examined using immunohistochemistry. Vitamin D supplementation had no significant effects on RV replication, but potentiated secretion of CXCL8 and CXCL10 from infected or uninfected cells. Treatment with vitamin D in the form of 1,25(OH)2D caused significant changes in cell morphology, including thickening of the cell layers (median of 46.5 µm [35.0-69.0] vs. 30 µm [24.5-34.2], p<0.01) and proliferation of cytokeratin-5-expressing cells, as demonstrated by immunohistochemical analysis. Similar effects were seen for 25(OH)D. In addition to altering morphology, higher concentrations of vitamin D significantly upregulated small proline-rich protein (SPRR1ß) expression (6.3 fold-induction, p<0.01), suggestive of squamous metaplasia. Vitamin D treatment of hBECs did not alter repair of mechanically induced wounds. Collectively, these findings indicate that vitamin D does not directly affect RV replication in airway epithelial cells, but can influence chemokine synthesis and alters the growth and differentiation of airway epithelial cells.

In vitro anti-influenza A H1N1 effect of extract of Bupleuri Radix.

This study investigated the effect of the extract of Bupleuri Radix (BRE) on the infection of Madin-Darby Canine Kidney (MDCK) cells by anti-H1N1 virus. The effect of BRE on RANTES (the chemokine regulated on activation, normal T cells expressed and secreted) secretion in H1N1-infected A549 cells (human bronchial epithelial cells) was evaluated via quantative measurement of the changes in the cytopathic effects and by the ultraviolet (UV) absorbance at 600 nm. It was found that BRE was toxic to MDCK cells at a higher concentration while had a marked inhibitory effect on cell pathological changes at a lower concentration. Results also showed that BRE possessed more than 50% suppressing effect on RANTES secretion in H1N1-infected A549 cells at a concentration of 100 and 200 µg/ml. Our findings show that BRE has a significant protective effect on MDCK cells infected in a dose-dependent manner with an excellent suppressing effect on RANTES secretion, suggesting that BRE can be developed as an antivirus agent.

Azithromycin induces anti-viral responses in bronchial epithelial cells.

The majority of asthma exacerbations are caused by rhinovirus. Currently the treatment of asthma exacerbations is inadequate. Previous evidence suggests that macrolide antibiotics have anti-inflammatory and antiviral effects; however, the mechanism is unknown. We investigated the anti-rhinoviral potential of macrolides through the induction of antiviral gene mRNA and protein. Primary human bronchial epithelial cells were pre-treated with the macrolides azithromycin, erythromycin and telithromycin, and infected with minor-group rhinovirus 1B and major-group rhinovirus 16. The mRNA expression of the antiviral genes, type I interferon-ß and type III interferon-λ1, interferon-λ2/3, and interferon-stimulated genes (retinoic acid inducible gene I, melanoma differentiation associated gene 5, oligoadenylate synthase, MxA and viperin) and pro-inflammatory cytokines (interleukin (IL)-6 and IL-8), and rhinovirus replication and release were measured. Azithromycin, but not erythromycin or telithromycin, significantly increased rhinovirus 1B- and rhinovirus 16-induced interferons and interferon-stimulated gene mRNA expression and protein production. Furthermore, azithromycin significantly reduced rhinovirus replication and release. Rhinovirus induced IL-6 and IL-8 protein and mRNA expression were not significantly reduced by azithromycin pre-treatment. In conclusion, the results demonstrate that azithromycin has anti-rhinoviral activity in bronchial epithelial cells and, during rhinovirus infection, increases the production of interferon-stimulated genes.

Dual regulatory effect of plant extracts of Forsythia suspense on RANTES and MCP-1 secretion in influenza A virus-infected human bronchial epithelial cells.

In this study, we investigated the effects of 95% ethanol (FS-t1), 50% ethanol (FS-t2) and water (FS-w) extracts of Forsythia suspense Vahl (Oleaceae) on the production of regulated on activation, normal T cell expressed and secreted (RANTES) and macrophage chemotactic protein-1 (MCP-1) by influenza A virus (H1N1)-infected human bronchial epithelial cell line A549. Virus infection evoked a markedly enhanced production of RANTES from basal 16 +/- 4 to 1307 +/- 294 pg/ml after 72 h inoculation. At the non-cytotoxic doses (20, 100 and 200 microg/ml), FS-t1, FS-t2 and FS-w exhibited a consistent inhibitory effect on virus-stimulated RANTES secretion in a dose-dependent manner wilh IC(50) of 42 +/- 6, 117 +/- 15 and 232 +/- 28 microg/ml, respectively. H1N1 also stimulated MCP-1 production in A549 cells, however to a less degree, from basal 133 +/- 21 to 391 +/- 98 pg/ml after 72 h viral inoculation. The effects of three extracts on MCP-1 secretion were more complex. FS-t1 displayed both positive and negative effect on virus-stimulated MCP-1 production dependent on the concentrations used. On the other hand, FS-t2 increased virus-induced MCP-1 secretion by 1.4-3.3 times while the third fraction FO-w increased by 2.6-3.7 times. These results suggested that Forsythia suspense consisted of both negative and positive regulatory components on RANTES and MCP-1 secretion in H1N1-infected A549 cells, respectively.

Pathogenesis of infection induced by an adenovirus isolated from a goat.

OBJECTIVE: To determine the pathogenic potential of an adenovirus isolated from a goat. ANIMALS: 14 colostrum-deprived, isolation-reared goat kids approximately 3 weeks old. PROCEDURE: Kids were inoculated with either cell culture fluid containing adenovirus (n = 10) or uninfected cell culture fluid (n = 4): 2 ml transtracheally and 1 ml/nostril. Clinical signs of disease and rectal temperature were recorded daily; nasal secretion and fecal specimens were collected daily. Control kids were necropsied, 2/d, on postinoculation days (PID) 5 and 10. Virus-inoculated kids were necropsied on PID 3, 5, 7, 10, and 28. After necropsy, lung, liver, kidney, and brain specimens were aseptically collected for virus isolation attempts. Tracheal fluid was collected on sterile cotton swabs. Turbinate, trachea, lung, mediastinal lymph node, liver, kidney, duodenum, jejunum, ileum, mesenteric lymph node, colon, and brain specimens were collected for histologic evaluation. RESULTS: Kids developed mild-to-moderate clinical respiratory tract infection. Virus was recovered consistently from nasal secretion and sporadically from fecal specimens. Grossly, there were multiple areas of atelectasis and hyperemia, principally in the cranioventral portion of the lungs. Microscopically, there was detachment and sloughing of foci of epithelial cells of the terminal bronchioles and alveoli. In kids necropsied late in the disease, these changes were accompanied by hyperplasia of type-II epithelial cells. Viral inclusions were not an obvious feature, but a few cells contained probable inclusions. CONCLUSIONS AND CLINICAL RELEVANCE: The caprine adenovirus reported here is capable of inducing respiratory tract disease and lesions in the lungs of young kids.