{"title":"[Urolithin A alleviates respiratory syncytial virus-induced lung infection in neonatal mice by activating miR-136-mediated Sirt1 signaling].","authors":"H Wang, H Xie, W Xu, M Li","doi":"10.12122/j.issn.1673-4254.2024.07.17","DOIUrl":null,"url":null,"abstract":"<p><strong>Objective: </strong>To observe the therapeutic effects of urolithin A (UA) on respiratory syncytial virus (RSV)-induced lung infection in neonatal mice and explore the underlying mechanisms.</p><p><strong>Methods: </strong>Babl/c mice (5-7 days old) were subjected to nasal instillation of RSV and received intraperitoneal injection of saline or 2.5, 5 and 10 mg/kg UA 2 h after the infection and then once daily for 2 weeks. Bronchoalveolar lavage fluid (BALF) was then collected for detection of inflammatory cells and mediators, and lung pathology was evaluated with HE staining. RSV-infected BEAS-2B cells were treated with 2.5, 5 or 10 µmol/ L UA. Inflammatory factors, cell viability, apoptosis and autophagy were analyzed using ELISA, CCK-8 assay, TUNEL staining, flow cytometry, Western blotting and immunofluorescence staining. The cellular expressions of miR-136 and Sirt1 mRNAs were detected using qRT-PCR. A dual-luciferase reporter system was used to verify the binding between miR-136 and Sirt1.</p><p><strong>Results: </strong>In neonatal Babl/c mice, RSV infection caused obvious lung pathologies, promoted pulmonary cell apoptosis and LC3-Ⅱ/Ⅰ, Beclin-1 and miR-136 expressions, and increased the total cell number, inflammatory cells and factors in the BALF and decreased p62 and Sirt1 expressions. All these changes were alleviated dose-dependently by UA. In BEAS-2B cells, RSV infection significantly increased cell apoptosis, LC3B-positive cells and miR-136 expression and reduced Sirt1 expression (<i>P</i><0.01), which were dose-dependently attenuated by UA. Dual-luciferase reporter assay confirmed the binding between miR-136 and Sirt1. In RSV-infected BEAS-2B cells with UA treatment, overexpression of miR-136 and Ex527 treatment both significantly increased the inflammatory factors and cell apoptosis but decreased LC3B expression, and these changes were further enhanced by their combined treatment.</p><p><strong>Conclusion: </strong>UA ameliorates RSV-induced lung infection in neonatal mice by activating miR-136-mediated Sirt1 signaling pathway.</p>","PeriodicalId":18962,"journal":{"name":"Nan fang yi ke da xue xue bao = Journal of Southern Medical University","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"2024-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11270657/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Nan fang yi ke da xue xue bao = Journal of Southern Medical University","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.12122/j.issn.1673-4254.2024.07.17","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"Medicine","Score":null,"Total":0}
引用次数: 0
Abstract
Objective: To observe the therapeutic effects of urolithin A (UA) on respiratory syncytial virus (RSV)-induced lung infection in neonatal mice and explore the underlying mechanisms.
Methods: Babl/c mice (5-7 days old) were subjected to nasal instillation of RSV and received intraperitoneal injection of saline or 2.5, 5 and 10 mg/kg UA 2 h after the infection and then once daily for 2 weeks. Bronchoalveolar lavage fluid (BALF) was then collected for detection of inflammatory cells and mediators, and lung pathology was evaluated with HE staining. RSV-infected BEAS-2B cells were treated with 2.5, 5 or 10 µmol/ L UA. Inflammatory factors, cell viability, apoptosis and autophagy were analyzed using ELISA, CCK-8 assay, TUNEL staining, flow cytometry, Western blotting and immunofluorescence staining. The cellular expressions of miR-136 and Sirt1 mRNAs were detected using qRT-PCR. A dual-luciferase reporter system was used to verify the binding between miR-136 and Sirt1.
Results: In neonatal Babl/c mice, RSV infection caused obvious lung pathologies, promoted pulmonary cell apoptosis and LC3-Ⅱ/Ⅰ, Beclin-1 and miR-136 expressions, and increased the total cell number, inflammatory cells and factors in the BALF and decreased p62 and Sirt1 expressions. All these changes were alleviated dose-dependently by UA. In BEAS-2B cells, RSV infection significantly increased cell apoptosis, LC3B-positive cells and miR-136 expression and reduced Sirt1 expression (P<0.01), which were dose-dependently attenuated by UA. Dual-luciferase reporter assay confirmed the binding between miR-136 and Sirt1. In RSV-infected BEAS-2B cells with UA treatment, overexpression of miR-136 and Ex527 treatment both significantly increased the inflammatory factors and cell apoptosis but decreased LC3B expression, and these changes were further enhanced by their combined treatment.
Conclusion: UA ameliorates RSV-induced lung infection in neonatal mice by activating miR-136-mediated Sirt1 signaling pathway.