scholarly journals Titanium dioxide nanoparticles exaggerate respiratory syncytial virus-induced airway epithelial barrier dysfunction

2020 ◽  
Vol 319 (3) ◽  
pp. L481-L496
Author(s):  
Carrie C. Smallcombe ◽  
Terri J. Harford ◽  
Debra T. Linfield ◽  
Susana Lechuga ◽  
Vladimir Bokun ◽  
...  
Keyword(s):  
Titanium Dioxide ◽  
Respiratory Syncytial Virus ◽  
Titanium Dioxide Nanoparticles ◽  
Airway Disease ◽  
Epithelial Barrier ◽  
Airway Epithelial ◽  
Barrier Dysfunction ◽  
Syncytial Virus ◽  
Epithelial Barrier Dysfunction

Respiratory syncytial virus (RSV) is the leading cause of lower respiratory tract infections in children worldwide. While most develop a mild, self-limiting illness, some develop severe acute lower respiratory infection and persistent airway disease. Exposure to ambient particulate matter has been linked to asthma, bronchitis, and viral infection in multiple epidemiological studies. We hypothesized that coexposure to nanoparticles worsens RSV-induced airway epithelial barrier dysfunction. Bronchial epithelial cells were incubated with titanium dioxide nanoparticles (TiO2-NP) or a combination of TiO2-NP and RSV. Structure and function of epithelial cell barrier were analyzed. Viral titer and the role of reactive oxygen species (ROS) generation were evaluated. In vivo, mice were intranasally incubated with TiO2-NP, RSV, or a combination. Lungs and bronchoalveolar lavage (BAL) fluid were harvested for analysis of airway inflammation and apical junctional complex (AJC) disruption. RSV-induced AJC disruption was amplified by TiO2-NP. Nanoparticle exposure increased viral infection in epithelial cells. TiO2-NP induced generation of ROS, and pretreatment with antioxidant, N-acetylcysteine, reversed said barrier dysfunction. In vivo, RSV-induced injury and AJC disruption were augmented in the lungs of mice given TiO2-NP. Airway inflammation was exacerbated, as evidenced by increased white blood cell infiltration into the BAL, along with exaggeration of peribronchial inflammation and AJC disruption. These data demonstrate that TiO2-NP exposure exacerbates RSV-induced AJC dysfunction and increases inflammation by mechanisms involving generation of ROS. Further studies are required to determine whether NP exposure plays a role in the health disparities of asthma and other lung diseases, and why some children experience more severe airway disease with RSV infection.

scholarly journals Disruption of the airway epithelial barrier in a murine model of respiratory syncytial virus infection

2019 ◽  
Vol 316 (2) ◽  
pp. L358-L368 ◽  
Author(s):  
Carrie C. Smallcombe ◽  
Debra T. Linfield ◽  
Terri J. Harford ◽  
Vladimir Bokun ◽  
Andrei I. Ivanov ◽  
...  
Keyword(s):  
Respiratory Syncytial Virus ◽  
Epithelial Cells ◽  
Tight Junction ◽  
Epithelial Barrier ◽  
Airway Epithelial ◽  
Barrier Dysfunction ◽  
Rsv Infection ◽  
Syncytial Virus

Respiratory syncytial virus (RSV) is a major cause of hospitalization for infants and young children worldwide. RSV is known to infect epithelial cells and increase the permeability of model airway epithelial monolayers in vitro. We hypothesized that RSV infection also induces airway barrier dysfunction in vivo. C57BL/6 mice were intranasally inoculated with RSV, and on day 4 post-inoculation were examined for viral replication, lung inflammation, and barrier integrity as well as the structure and molecular composition of epithelial junctions. In parallel, primary mouse tracheal epithelial cells (mTEC) were cultured for in vitro studies. RSV-infected mice lost weight and showed significant peribronchial inflammation compared with noninfected controls and UV-inactivated RSV-inoculated animals. RSV infection increased the permeability of the airway epithelial barrier and altered the molecular composition of epithelial tight junctions. The observed RSV-induced barrier disruption was accompanied by decreased expression of several tight-junction proteins and accumulation of cleaved extracellular fragments of E-cadherin in bronchoalveolar lavage and mTEC supernatants. Similarly, in vitro RSV infection of mTEC monolayers resulted in enhanced permeability and disruption of tight-junction structure. Furthermore, incubation of mTEC monolayers with a recombinant fragment of E-cadherin caused tight-junction disassembly. Taken together, these data indicate that RSV infection leads to airway barrier dysfunction in vivo, mediated by either decreased expression or cleavage of junctional proteins. Our observations provide further insights into the pathophysiology of RSV infection and provide a rationale for development of barrier-protecting agents to alleviate the pathogenic effects of RSV infection.

scholarly journals The role of secreted Hsp90α in HDM-induced asthmatic airway epithelial barrier dysfunction

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Cuiping Ye ◽  
Chaowen Huang ◽  
Mengchen Zou ◽  
Yahui Hu ◽  
Lishan Luo ◽  
...  
Keyword(s):  
Barrier Function ◽  
Epithelial Barrier ◽  
Airway Epithelial ◽  
Barrier Dysfunction ◽  
Epithelial Barrier Function ◽  
Asthmatic Airway ◽  
Epithelial Barrier Dysfunction

Abstract Background The dysfunction of airway epithelial barrier is closely related to the pathogenesis of asthma. Secreted Hsp90α participates in inflammation and Hsp90 inhibitor protects endothelial dysfunction. In the current study, we aimed to explore the role of secreted Hsp90α in asthmatic airway epithelial barrier function. Methods Male BALB/c mice were sensitized and challenged with HDM to generate asthma model. The 16HBE and Hsp90α-knockdown cells were cultured and treated according to the experiment requirements. Transepithelial Electric Resistance (TEER) and permeability of epithelial layer in vitro, distribution and expression of junction proteins both in vivo and in vitro were used to evaluate the epithelial barrier function. Western Blot was used to evaluate the expression of junction proteins and phosphorylated AKT in cells and lung tissues while ELISA were used to evaluate the Hsp90α expression and cytokines release in the lung homogenate. Results HDM resulted in a dysfunction of airway epithelial barrier both in vivo and in vitro, paralleled with the increased expression and release of Hsp90α. All of which were rescued in Hsp90α-knockdown cells or co-administration of 1G6-D7. Furthermore, either 1G6-D7 or PI3K inhibitor LY294002 suppressed the significant phosphorylation of AKT, which caused by secreted and recombinant Hsp90α, resulting in the restoration of epithelial barrier function. Conclusions Secreted Hsp90α medicates HDM-induced asthmatic airway epithelial barrier dysfunction via PI3K/AKT pathway, indicating that anti-secreted Hsp90α therapy might be a potential treatment to asthma in future.

scholarly journals A Novel Serine Protease Inhibitor PE-BBI Ameliorates Cockroach Extract-Mediated Airway Epithelial Barrier Dysfunction

Biomolecules ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 515
Author(s):  
James A. Reihill ◽  
Xuan Ouyang ◽  
Zhixuan Yang ◽  
Lisa E. J. Douglas ◽  
Mei Zhou ◽  
...  
Keyword(s):  
Protease Inhibitor ◽  
Airway Disease ◽  
Allergic Airway Disease ◽  
Epithelial Barrier ◽  
Epithelial Cell Line ◽  
Airway Epithelial ◽  
Barrier Dysfunction ◽  
Barrier Disruption ◽  
Cockroach Extract ◽  
Epithelial Barrier Dysfunction

Epithelial barrier dysfunction, characteristic of allergic airway disease may be, at least in part, due to the action of allergen-associated protease activities. Cockroach allergy is a major global health issue, with cockroaches containing considerable serine trypsin-like protease (TLP) activity. The present study sought to evaluate two novel protease inhibitors (PE-BBI and pLR-HL), recently isolated from amphibian skin secretions, for their potential to neutralise cockroach TLP activity and to determine any protective effect on cockroach-induced airway epithelial barrier disruption. Inhibitor potencies against the cockroach-associated activities were determined using a fluorogenic peptide substrate-based activity assay. 16HBE14o- cells (16HBE; a bronchial epithelial cell line) were treated with cockroach extract (CRE) in the presence or absence of the compounds in order to assess cell viability (RealTime Glo luminescent assay) and epithelial barrier disruption (transepithelial resistance and paracellular dextran flux). PE-BBI potently and selectively inhibited CRE TLP activity (pIC50 -8), but not host (16HBE) cell surface activity, which conferred protection of 16HBE cells from CRE-induced cell damage and barrier disruption. Novel protease inhibitor strategies such as PE-BBI may be useful for the treatment of allergic airway disease caused by cockroach proteases.

scholarly journals Restoring airway epithelial barrier dysfunction: a new therapeutic challenge in allergic airway disease

2017 ◽  
Vol 54 (3) ◽  
pp. 195-205 ◽  
Author(s):  
B. Steelant ◽  
S.F. Seys ◽  
G. Boeckxstaens ◽  
C.A. Akdis ◽  
J.L. Ceuppens ◽  
...  
Keyword(s):  
Airway Disease ◽  
Allergic Airway Disease ◽  
Epithelial Barrier ◽  
Airway Epithelial ◽  
Barrier Dysfunction ◽  
Therapeutic Challenge ◽  
Epithelial Barrier Dysfunction

scholarly journals Bacteroides fragilis defense against Cronobacter sakazakii-induced pathogenicity by regulating the intestinal epithelial barrier function and attenuating both apoptotic and pyroptotic cell death

2018 ◽  
Author(s):  
Hongying Fan ◽  
Ruqin Lin ◽  
Zhenhui Chen ◽  
Xingyu Leng ◽  
Xianbo Wu ◽  
...  
Keyword(s):  
Cell Death ◽  
Necrotizing Enterocolitis ◽  
Neonatal Rat ◽  
Epithelial Barrier ◽  
Intestinal Epithelial ◽  
Cronobacter Sakazakii ◽  
Barrier Dysfunction ◽  
Epithelial Barrier Dysfunction

AbstractCronobacter sakazakii (CS), an important pathogen, is associated with the development of necrotizing enterocolitis (NEC), infant sepsis, and meningitis. Several randomized prospective clinical trials demonstrated that oral probiotics could decrease the incidence of NEC. Previously, we isolated and characterized a novel probiotic, B. fragilis strain ZY-312. However, it remains unclear how ZY-312 protects the host from the effects of CS infection. To understand the underlying mechanisms triggering the probiotic effects, we tested the hypothesis that there was a cross-talk between probiotics/probiotics-modulated microbiota and the local immune system, governed by the permeability of the intestinal mucosa using in vitro and in vivo models for the intestinal permeability. The probiotic effects of ZY-312 on intestinal epithelial cells were first examined, which revealed that ZY-312 inhibited CS invasion, CS-induced dual cell death (pyroptosis and apoptosis), and epithelial barrier dysfunction in vitro and in vivo. ZY-312 also decreased the expression of an inflammasome (NOD-like receptor family member pyrin domain-containing protein 3 (NLRP3), caspase-3, and serine protease caspase-1 in a neonatal rat model. Furthermore, ZY-312 significantly modulated the compositions of the intestinal bacterial communities, and decreased the relative abundances of Proteobacteria, Gamma proteobacteria, but increased the relative abundance of Bacteroides and Bacillus in neonatal rats. In conclusion, our findings have shown for the first time that the probiotic, B. fragilis ZY-312, suppresses CS-induced NEC by modulating the pro-inflammatory response and dual cell death (apoptosis and pyroptosis).Author summaryCronobacter sakazakii, a major necrotizing enterocolitis pathogen, is used as a model microorganism for the study of opportunistic bacteria in the pathogenesis of necrotizing enterocolitis. Here, we have now unequivocally demonstrated that both apoptotic and pyroptotic stimuli contribute to the pathogenesis of Cronobacter sakazakii -induced necrotizing enterocolitis. Previously, we isolated and characterized a novel probiotic, B. fragilis strain ZY-312. We found that the ZY-312 defense against Cronobacter sakazakii-induced necrotizing enterocolitis by inhibiting Cronobacter sakazakii invasion, epithelial barrier dysfunction, the expression of inflammatory cytokines and dual cell death (pyroptosis and apoptosis). This study demonstrates the utility of ZY-312 as a promising probiotic agent for the prevention and treatment of various intestinal diseases, including NEC.

scholarly journals Advanced Organ-on-a-Chip Devices to Investigate Liver Multi-Organ Communication: Focus on Gut, Microbiota and Brain

2019 ◽  
Vol 6 (4) ◽  
pp. 91 ◽  
Author(s):  
Lucia Boeri ◽  
Luca Izzo ◽  
Lorenzo Sardelli ◽  
Marta Tunesi ◽  
Diego Albani ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Epithelial Barrier ◽  
Intestinal Epithelial ◽  
Barrier Dysfunction ◽  
In Vitro Modeling ◽  
Reciprocal Influence ◽  
Organ On A Chip ◽  
Epithelial Barrier Dysfunction

The liver is a key organ that can communicate with many other districts of the human body. In the last few decades, much interest has focused on the interaction between the liver and the gut microbiota, with their reciprocal influence on biosynthesis pathways and the integrity the intestinal epithelial barrier. Dysbiosis or liver disorders lead to0 epithelial barrier dysfunction, altering membrane permeability to toxins. Clinical and experimental evidence shows that the permeability hence the delivery of neurotoxins such as LPS, ammonia and salsolinol contribute to neurological disorders. These findings suggested multi-organ communication between the gut microbiota, the liver and the brain. With a view to in vitro modeling this liver-based multi-organ communication, we describe the latest advanced liver-on-a-chip devices and discuss the need for new organ-on-a-chip platforms for in vitro modeling the in vivo multi-organ connection pathways in physiological and pathological situations.

Titanium dioxide nanoparticles exacerbate pneumonia in respiratory syncytial virus (RSV)-infected mice

2015 ◽  
Vol 39 (2) ◽  
pp. 879-886 ◽  
Author(s):  
Seiko Hashiguchi ◽  
Hiroki Yoshida ◽  
Toshi Akashi ◽  
Keiji Komemoto ◽  
Tomoyuki Ueda ◽  
...  
Keyword(s):  
Titanium Dioxide ◽  
Respiratory Syncytial Virus ◽  
Titanium Dioxide Nanoparticles ◽  
Syncytial Virus
Sign in / Sign up

Export Citation Format

Share Document