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Ottenio de Lourenço I, Toscano Pedroso Quintino E, Henrique Pereira M, Sprengel Lima C, Campos Araújo G, Octávio Regasini L, Alves de Melo F, Pereira de Souza F, Andres Fossey M, Putinhon Caruso Í. Biophysical studies of the interaction of hRSV Non-Structural 1 protein with natural flavonoids and their acetylated derivatives by spectroscopic techniques and computational simulations. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2022; 283:121751. [PMID: 35973382 DOI: 10.1016/j.saa.2022.121751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 07/14/2022] [Accepted: 08/09/2022] [Indexed: 06/15/2023]
Abstract
Human respiratory syncytial virus (hRSV) infections are one of the most causes of acute lower respiratory tract infections in children and elderly. The development of effective antiviral therapies or preventive vaccines against hRSV is not available yet. Thus, it is necessary to search for protein targets to combat this viral infection, as well as potential ways to block them. Non-Structural 1 (NS1) protein is an important factor for viral replication success since reduces the immune response by interacting with proteins in the type I interferon pathway. The influence of NS1 on the cell's immune response denotes the potential of its inhibition, being a possible target of treatment against hRSV infection. Here, it was studied the interaction of hRSV NS1 with natural flavonoids chrysin, morin, kaempferol, and myricetin and their mono-acetylated chrysin and penta-acetylated morin derivatives using spectroscopic techniques and computational simulations. The fluorescence data indicate that the binding affinities are on the order of 105 M-1, which are directly related to the partition coefficient of each flavonoid with Pearson's correlation coefficients of 0.76-0.80. The thermodynamic analysis suggests that hydrophobic interactions play a key role in the formation of the NS1/flavonoid complexes, with positive values of enthalpy and entropy changes. The computational approach proposes that flavonoids bind in a region of NS1 formed between the C-terminal α3-helix and the protein core, important for its biological function, and corroborate with experimental data revealing that hydrophobic contacts are important for the binding. Therefore, the present study provides relevant molecular details for the development of a possible new strategy to fight infections caused by hRSV.
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Affiliation(s)
- Isabella Ottenio de Lourenço
- Department of Physics, Institute of Biosciences, Letters and Exact Sciences (IBILCE), São Paulo State University "Júlio de Mesquita Filho" (UNESP), São José do Rio Preto, SP 15054-000, Brazil; Multiuser Center for Biomolecular Innovation (CMIB), Department of Physics, Institute of Biosciences, Letters and Exact Sciences (IBILCE), São Paulo State University "Júlio de Mesquita Filho" (UNESP), São José do Rio Preto, SP 15054-000, Brazil
| | - Evelyn Toscano Pedroso Quintino
- Multiuser Center for Biomolecular Innovation (CMIB), Department of Physics, Institute of Biosciences, Letters and Exact Sciences (IBILCE), São Paulo State University "Júlio de Mesquita Filho" (UNESP), São José do Rio Preto, SP 15054-000, Brazil
| | - Matheus Henrique Pereira
- Department of Chemistry and Environmental Sciences, Institute of Biosciences, Letters and Exact Sciences (IBILCE), São Paulo State University "Júlio de Mesquita Filho" (UNESP), São José do Rio Preto, SP 15054-000, Brazil
| | - Caroline Sprengel Lima
- Department of Chemistry and Environmental Sciences, Institute of Biosciences, Letters and Exact Sciences (IBILCE), São Paulo State University "Júlio de Mesquita Filho" (UNESP), São José do Rio Preto, SP 15054-000, Brazil
| | - Gabriela Campos Araújo
- Department of Physics, Institute of Biosciences, Letters and Exact Sciences (IBILCE), São Paulo State University "Júlio de Mesquita Filho" (UNESP), São José do Rio Preto, SP 15054-000, Brazil
| | - Luis Octávio Regasini
- Department of Chemistry and Environmental Sciences, Institute of Biosciences, Letters and Exact Sciences (IBILCE), São Paulo State University "Júlio de Mesquita Filho" (UNESP), São José do Rio Preto, SP 15054-000, Brazil
| | - Fernando Alves de Melo
- Department of Physics, Institute of Biosciences, Letters and Exact Sciences (IBILCE), São Paulo State University "Júlio de Mesquita Filho" (UNESP), São José do Rio Preto, SP 15054-000, Brazil; Multiuser Center for Biomolecular Innovation (CMIB), Department of Physics, Institute of Biosciences, Letters and Exact Sciences (IBILCE), São Paulo State University "Júlio de Mesquita Filho" (UNESP), São José do Rio Preto, SP 15054-000, Brazil
| | - Fátima Pereira de Souza
- Department of Physics, Institute of Biosciences, Letters and Exact Sciences (IBILCE), São Paulo State University "Júlio de Mesquita Filho" (UNESP), São José do Rio Preto, SP 15054-000, Brazil; Multiuser Center for Biomolecular Innovation (CMIB), Department of Physics, Institute of Biosciences, Letters and Exact Sciences (IBILCE), São Paulo State University "Júlio de Mesquita Filho" (UNESP), São José do Rio Preto, SP 15054-000, Brazil
| | - Marcelo Andres Fossey
- Department of Physics, Institute of Biosciences, Letters and Exact Sciences (IBILCE), São Paulo State University "Júlio de Mesquita Filho" (UNESP), São José do Rio Preto, SP 15054-000, Brazil; Multiuser Center for Biomolecular Innovation (CMIB), Department of Physics, Institute of Biosciences, Letters and Exact Sciences (IBILCE), São Paulo State University "Júlio de Mesquita Filho" (UNESP), São José do Rio Preto, SP 15054-000, Brazil.
| | - Ícaro Putinhon Caruso
- Department of Physics, Institute of Biosciences, Letters and Exact Sciences (IBILCE), São Paulo State University "Júlio de Mesquita Filho" (UNESP), São José do Rio Preto, SP 15054-000, Brazil; Multiuser Center for Biomolecular Innovation (CMIB), Department of Physics, Institute of Biosciences, Letters and Exact Sciences (IBILCE), São Paulo State University "Júlio de Mesquita Filho" (UNESP), São José do Rio Preto, SP 15054-000, Brazil; Institute of Medical Biochemistry Leopoldo de Meis and National Center for Structural Biology and Bioimaging, Federal University of Rio de Janeiro, Rio de Janeiro, RJ 21941-902, Brazil.
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Lee ZY, Tam JKC, Tran T. Corticosteroid use in respiratory viral infections — friend or foe? CURRENT OPINION IN PHYSIOLOGY 2021. [DOI: 10.1016/j.cophys.2021.06.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Thornhill EM, Verhoeven D. Respiratory Syncytial Virus's Non-structural Proteins: Masters of Interference. Front Cell Infect Microbiol 2020; 10:225. [PMID: 32509597 PMCID: PMC7248305 DOI: 10.3389/fcimb.2020.00225] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Accepted: 04/22/2020] [Indexed: 01/12/2023] Open
Abstract
Respiratory Syncytial Virus (RSV) is a highly prevalent virus that affects the majority of the population. The virus can cause severe disease in vulnerable populations leading to high hospitalization rates from bronchiolitis or secondary bacterial infections leading to pneumonia. Two early and non-structural proteins (Ns1 and Ns2), strongly over-ride the antiviral innate system but also diminish the adaptive response as well. This review will cover interactions of Ns1 and Ns2 with the host antiviral response with a focus on alterations to signaling pathways, cytokine gene expression, and effects of the Ns proteins on mitochondria.
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Affiliation(s)
| | - David Verhoeven
- Veterinary Microbiology and Preventive Medicine, Iowa State University, Ames, IA, United States
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McAllister CS, Ansaldi D, Growcott EJ, Zhong Y, Quackenbush D, Wolff KC, Chen Z, Tanaseichuk O, Lelais G, Barnes SW, Federe GC, Luna F, Walker JR, Zhou Y, Kuhen KL. Dexamethasone inhibits respiratory syncytial virus-driven mucus production while increasing viral replication without altering antiviral interferon signaling. Virology 2019; 540:195-206. [PMID: 31929001 DOI: 10.1016/j.virol.2019.10.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 09/23/2019] [Accepted: 10/18/2019] [Indexed: 01/03/2023]
Abstract
Respiratory syncytial virus (RSV) infection can cause mucus overproduction and bronchiolitis in infants leading to severe disease and hospitalization. As a therapeutic strategy, immune modulatory agents may help prevent RSV-driven immune responses that cause severe airway disease. We developed a high throughput screen to identify compounds that reduced RSV-driven mucin 5AC (Muc5AC) expression and identified dexamethasone. Despite leading to a pronounced reduction in RSV-driven Muc5AC, dexamethasone increased RSV infection in vitro and delayed viral clearance in mice. This correlated with reduced expression of a subset of immune response genes and reduced lymphocyte infiltration in vivo. Interestingly, dexamethasone increased RSV infection levels without altering antiviral interferon signaling. In summary, the immunosuppressive activities of dexamethasone had favorable inhibitory effects on RSV-driven mucus production yet prevented immune defense activities that limit RSV infection in vitro and in vivo. These findings offer an explanation for the lack of efficacy of glucocorticoids in RSV-infected patients.
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Affiliation(s)
| | - Dan Ansaldi
- Novartis Institute for BioMedical Research, Emeryville, CA, USA
| | | | - Yang Zhong
- Genomics Institute of the Novartis Research Foundation, San Diego, CA, USA
| | - Doug Quackenbush
- Genomics Institute of the Novartis Research Foundation, San Diego, CA, USA
| | - Karen C Wolff
- Genomics Institute of the Novartis Research Foundation, San Diego, CA, USA
| | - Zhong Chen
- Genomics Institute of the Novartis Research Foundation, San Diego, CA, USA
| | - Olga Tanaseichuk
- Genomics Institute of the Novartis Research Foundation, San Diego, CA, USA
| | - Gerald Lelais
- Genomics Institute of the Novartis Research Foundation, San Diego, CA, USA
| | - S Whitney Barnes
- Genomics Institute of the Novartis Research Foundation, San Diego, CA, USA
| | - Glenn C Federe
- Genomics Institute of the Novartis Research Foundation, San Diego, CA, USA
| | - Fabio Luna
- Genomics Institute of the Novartis Research Foundation, San Diego, CA, USA
| | - John R Walker
- Genomics Institute of the Novartis Research Foundation, San Diego, CA, USA
| | - Yingyao Zhou
- Genomics Institute of the Novartis Research Foundation, San Diego, CA, USA
| | - Kelli L Kuhen
- Genomics Institute of the Novartis Research Foundation, San Diego, CA, USA
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Respiratory syncytial virus nonstructural proteins 1 and 2: Exceptional disrupters of innate immune responses. PLoS Pathog 2019; 15:e1007984. [PMID: 31622448 PMCID: PMC6797084 DOI: 10.1371/journal.ppat.1007984] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Human respiratory syncytial virus (RSV) is the most important cause of acute lower respiratory tract disease in infants worldwide. As a first line of defense against respiratory infections, innate immune responses, including the production of type I and III interferons (IFNs), play an important role. Upon infection with RSV, multiple pattern recognition receptors (PRRs) can recognize RSV-derived pathogen-associated molecular patterns (PAMPs) and mount innate immune responses. Retinoic-acid-inducible gene-I (RIG-I) and nucleotide-binding oligomerization domain-containing protein 2 (NOD2) have been identified as important innate receptors to mount type I IFNs during RSV infection. However, type I IFN levels remain surprisingly low during RSV infection despite strong viral replication. The poor induction of type I IFNs can be attributed to the cooperative activity of 2 unique, nonstructural (NS) proteins of RSV, i.e., NS1 and NS2. These viral proteins have been shown to suppress both the production and signaling of type I and III IFNs by counteracting a plethora of key host innate signaling proteins. Moreover, increasing numbers of IFN-stimulated genes (ISGs) are being identified as targets of the NS proteins in recent years, highlighting an underexplored protein family in the identification of NS target proteins. To understand the diverse effector functions of NS1 and NS2, Goswami and colleagues proposed the hypothesis of the NS degradasome (NSD) complex, a multiprotein complex made up of, at least, NS1 and NS2. Furthermore, the crystal structure of NS1 was resolved recently and, remarkably, identified NS1 as a structural paralogue of the RSV matrix protein. Unfortunately, no structural data on NS2 have been published so far. In this review, we briefly describe the PRRs that mount innate immune responses upon RSV infection and provide an overview of the various effector functions of NS1 and NS2. Furthermore, we discuss the ubiquitination effector functions of NS1 and NS2, which are in line with the hypothesis that the NSD shares features with the canonical 26S proteasome.
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Gao L, Mo S, Xie J, Chen S, Wen X, Long X, Ren L, Zang N, Xie X, Deng Y, Luo J, Luo Z, Fu Z, Smyth RL, Liu E. Respiratory syncytial virus nonstructural protein 1 downregulates glucocorticoid receptor expression through miR-29a. J Allergy Clin Immunol 2019; 144:854-857.e6. [PMID: 31128120 DOI: 10.1016/j.jaci.2019.05.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 05/02/2019] [Accepted: 05/08/2019] [Indexed: 11/26/2022]
Affiliation(s)
- Leiqiong Gao
- Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, Key Laboratory of Pediatrics in Chongqing, CSTC2009CA5002, Chongqing International Science and Technology Cooperation Center for Child Development and Disorders, Chongqing, China
| | - Shi Mo
- Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, Key Laboratory of Pediatrics in Chongqing, CSTC2009CA5002, Chongqing International Science and Technology Cooperation Center for Child Development and Disorders, Chongqing, China
| | - Jun Xie
- Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, Key Laboratory of Pediatrics in Chongqing, CSTC2009CA5002, Chongqing International Science and Technology Cooperation Center for Child Development and Disorders, Chongqing, China
| | - Sisi Chen
- Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, Key Laboratory of Pediatrics in Chongqing, CSTC2009CA5002, Chongqing International Science and Technology Cooperation Center for Child Development and Disorders, Chongqing, China
| | - Xiang Wen
- Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, Key Laboratory of Pediatrics in Chongqing, CSTC2009CA5002, Chongqing International Science and Technology Cooperation Center for Child Development and Disorders, Chongqing, China
| | - Xiaoru Long
- Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, Key Laboratory of Pediatrics in Chongqing, CSTC2009CA5002, Chongqing International Science and Technology Cooperation Center for Child Development and Disorders, Chongqing, China
| | - Luo Ren
- Pediatric Research Institute, Ministry of Education Key Laboratory of Child Development and Disorders, Key Laboratory of Pediatrics in Chongqing, CSTC2009CA5002, Chongqing International Science and Technology Cooperation Center for Child Development and Disorders, Chongqing, China
| | - Na Zang
- Department of Respiratory Medicine, Children's Hospital, Chongqing Medical University, Chongqing, China
| | - Xiaohong Xie
- Department of Respiratory Medicine, Children's Hospital, Chongqing Medical University, Chongqing, China
| | - Yu Deng
- Department of Respiratory Medicine, Children's Hospital, Chongqing Medical University, Chongqing, China
| | - Jian Luo
- Department of Respiratory Medicine, Children's Hospital, Chongqing Medical University, Chongqing, China
| | - Zhengxiu Luo
- Department of Respiratory Medicine, Children's Hospital, Chongqing Medical University, Chongqing, China
| | - Zhou Fu
- Department of Respiratory Medicine, Children's Hospital, Chongqing Medical University, Chongqing, China
| | - Rosalind L Smyth
- University College London (UCL), Great Ormond Street Institute of Child Health, London, United Kingdom
| | - Enmei Liu
- Department of Respiratory Medicine, Children's Hospital, Chongqing Medical University, Chongqing, China.
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Martín-Vicente M, Resino S, Martínez I. siRNA-Mediated Simultaneous Regulation of the Cellular Innate Immune Response and Human Respiratory Syncytial Virus Replication. Biomolecules 2019; 9:biom9050165. [PMID: 31035368 PMCID: PMC6572644 DOI: 10.3390/biom9050165] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 04/22/2019] [Accepted: 04/23/2019] [Indexed: 12/15/2022] Open
Abstract
Human respiratory syncytial virus (HRSV) infection is a common cause of severe lower respiratory tract diseases such as bronchiolitis and pneumonia. Both virus replication and the associated inflammatory immune response are believed to be behind these pathologies. So far, no vaccine or effective treatment is available for this viral infection. With the aim of finding new strategies to counteract HRSV replication and modulate the immune response, specific small interfering RNAs (siRNAs) were generated targeting the mRNA coding for the viral fusion (F) protein or nucleoprotein (N), or for two proteins involved in intracellular immune signaling, which are named tripartite motif-containing protein 25 (TRIM25) and retinoic acid-inducible gene-I (RIG-I). Furthermore, two additional bispecific siRNAs were designed that silenced F and TRIM25 (TRIM25/HRSV-F) or N and RIG-I (RIG-I/HRSV-N) simultaneously. All siRNAs targeting N or F, but not those silencing TRIM25 or RIG-I alone, significantly reduced viral titers. However, while siRNAs targeting F inhibited only the expression of the F mRNA and protein, the siRNAs targeting N led to a general inhibition of viral mRNA and protein expression. The N-targeting siRNAs also induced a drastic decrease in the expression of genes of the innate immune response. These results show that both virus replication and the early innate immune response can be regulated by targeting distinct viral products with siRNAs, which may be related to the different role of each protein in the life cycle of the virus.
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MESH Headings
- Base Sequence
- Cell Line, Tumor
- Gene Expression Regulation, Viral
- Gene Silencing
- Genome, Viral
- Humans
- Immunity, Innate/genetics
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Small Interfering/metabolism
- RNA, Viral/metabolism
- Respiratory Syncytial Virus, Human/genetics
- Respiratory Syncytial Virus, Human/growth & development
- Respiratory Syncytial Virus, Human/immunology
- Respiratory Syncytial Virus, Human/physiology
- Viral Proteins/genetics
- Viral Proteins/metabolism
- Virus Replication/physiology
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Affiliation(s)
- María Martín-Vicente
- Unidad de Infección Viral e Inmunidad, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain.
| | - Salvador Resino
- Unidad de Infección Viral e Inmunidad, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain.
| | - Isidoro Martínez
- Unidad de Infección Viral e Inmunidad, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain.
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Mucin 1 downregulation impairs the anti-necroptotic effects of glucocorticoids in human bronchial epithelial cells. Life Sci 2019; 221:168-177. [PMID: 30738043 DOI: 10.1016/j.lfs.2019.02.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Revised: 01/27/2019] [Accepted: 02/04/2019] [Indexed: 02/06/2023]
Abstract
AIMS To investigate whether mucin 1 (MUC1) downregulation reduced the sensitivity of tumor necrosis factor-alpha (TNF-α)-induced bronchial epithelial cells to glucocorticoid-mediated necroptosis and explore the underlying mechanisms. MAIN METHODS The human lung bronchial epithelial cell line (16HBE) was transfected with small interfering RNA (siRNA) against MUC1 and then stimulated by TNF-α, where some cells were pretreated with dexamethasone. Flow cytometry was performed to analyze necroptosis in 16HBE cells, and western blot analysis was used to detect protein expression levels of MUC1, glucocorticoid receptor (GR)α, GRβ, NF-κB p65, phospho-p65 (p-p65), and histone deacetylase-2 (HDAC2). Additionally, nuclear translocation of MUC1 and GRα was assessed by immunofluorescence. KEY FINDINGS We observed that MUC1 downregulation by siRNA significantly augmented TNF-α-induced necroptosis in 16HBE cells, and that dexamethasone showed impaired anti-necroptotic effects of MUC1 downregulation. Furthermore, we found that GRα nuclear translocation was inhibited in 16HBE cells with MUC1 downregulation, and that dexamethasone-mediated inhibition of p65 phosphorylation was lower in cells transfected with MUC1-siRNA compared to those transfected with negative control siRNA. SIGNIFICANCE Impaired GRα nuclear translocation and inhibited p-p65 expression might contribute to glucocorticoid resistance caused by MUC1 deficiency in TNF-α-induced necroptosis in 16HBE cells, and should be considered as a potential target for the development of novel therapeutics for asthma.
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Neonatal Streptococcus pneumoniae Pneumonia Induces an Aberrant Airway Smooth Muscle Phenotype and AHR in Mice Model. BIOMED RESEARCH INTERNATIONAL 2019; 2019:1948519. [PMID: 30723734 PMCID: PMC6339730 DOI: 10.1155/2019/1948519] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Revised: 11/12/2018] [Accepted: 12/23/2018] [Indexed: 12/21/2022]
Abstract
Our previous study showed that neonatal S. pneumoniae infection aggravated airway inflammation and airway hyperresponsiveness (AHR) in an OVA-induced allergic asthma model. As airway smooth muscle (ASM) plays a pivotal role in AHR development, we aim to investigate the effects of neonatal S. pneumoniae pneumonia on ASM structure and AHR development. Non-lethal neonatal pneumonia was established by intranasally infecting 1-week-old BALB/C mice with the S. pneumoniae strain D39. Five weeks after infection, the lungs were collected to assess the levels of α-SMA and the contractile proteins of ASM. Our results indicate that neonatal S. pneumoniae pneumonia significantly increased adulthood lung α-SMA and SMMHC proteins production and aggravated airway inflammatory cells infiltration and cytokines release. In addition, the neonatal S. pneumoniae pneumonia group had significantly higher Penh values compared to the uninfected controls. These data suggest that neonatal S. pneumoniae pneumonia promoted an aberrant ASM phenotype and AHR development in mice model.
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