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Math1, retinoic acid, and TNF-? synergistically promote the differentiation of mucous cells in mouse middle ear epithelial cells in vitro.

ABSTRACT: A key issue in otitis media (OM) is mucous cell metaplasia in the middle ear mucosa, a condition for hyperproduction of mucus in the middle ear mucosa and development of chronic OM. However, little is known about the driving force for the differentiation of mucous cells in OM.Mouse middle ear epithelial cells (mMEECs) were used in this study to test whether Math1, a critical transcription factor for the development of mucous cells in the intestine, synergizes with inflammatory cytokines (tumor necrosis factor-? (TNF-?)) and other epithelial differentiation factors (retinoid acid (RA)) to induce the differentiation of mMEECs into mucus-like cells in vitro. Simultaneously, Math1 was transduced into the middle ear mucosa in order to observe whether it induces mucous cell hyperplasia in vivo.Math1 significantly increased the mucus cell numbers in the middle ear mucosa of mice. Math1, in the presence of TNF-? and epithelial differentiation factor RA, synergistically promoted the differentiation of mMEECs into mucus-like cells through upregulation of mucins and their chaperones: trefoil factors in vitro. RA treatment for 12?h activated Math1, although RA alone had very limited effects on mucus-like cell differentiation.Math1 plays a critical role in the pathogenesis of OM by induction of mucous cell differentiation in the presence of TNF-? and RA.

SUBMITTER: Nakamura Y

PROVIDER: S-EPMC3766487 | biostudies-literature | 2013 Sep

REPOSITORIES: biostudies-literature

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Math1, retinoic acid, and TNF-α synergistically promote the differentiation of mucous cells in mouse middle ear epithelial cells in vitro.

Nakamura Yoshihisa Y Komori Masahiro M Yamakawa Kazuhiro K Hamajima Yuki Y Suzuki Motohiko M Kim Youngki Y Lin Jizhen J

Pediatric research 20130619 3

<h4>Background</h4>A key issue in otitis media (OM) is mucous cell metaplasia in the middle ear mucosa, a condition for hyperproduction of mucus in the middle ear mucosa and development of chronic OM. However, little is known about the driving force for the differentiation of mucous cells in OM.<h4>Methods</h4>Mouse middle ear epithelial cells (mMEECs) were used in this study to test whether Math1, a critical transcription factor for the development of mucous cells in the intestine, synergizes w ...[more]

PMID: 23783432

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Project description:Air-pollutants containing toxic particulate matters (PM) deposit in the respiratory tract and increases microbial infections. However, the mechanism by which this occurs is not well understood. This study evaluated the effect of urban particles (UP) on Streptococcus pneumoniae (pneumococcus) in vitro biofilm formation, colonization of human middle ear epithelium cells (HMEECs) as well as mouse nasal cavity and its transition to the middle ear and lungs. The in vitro biofilms and planktonic growth of S. pneumoniae were evaluated in metal ion free medium in the presence of UP. Biofilms were quantified by crystal violet (CV) microplate assay, colony forming unit (cfu) counts and resazurin staining. Biofilm structures were analyzed using a scanning electron microscope (SEM) and confocal microscopy (CM). Gene expressions of biofilms were evaluated using real time RT-PCR. Effects of UP exposure on S. pneumoniae colonization to HMEECs were evaluated using fluorescent in-situ hybridization (FISH), cell viability was detected using the Ezcyto kit, apoptosis in HMEECs were evaluated using Annexin-V/PI based cytometry analysis and reactive oxygen species (ROS) production were evaluated using the Oxiselect kit. Alteration of HMEECs gene expressions on UP exposure or pneumococci colonization was evaluated using microarray. In vivo colonization of pneumococci in the presence of UP and transition to middle ear and lungs were evaluated using an intranasal mice colonization model. The UP exposure significantly increased (*p < 0.05) pneumococcal in vitro biofilms and planktonic growth. In the presence of UP, pneumococci formed organized biofilms with a matrix, while in absence of UP bacteria were unable to form biofilms. The luxS, ply, lytA, comA, comB and ciaR genes involved in bacterial pathogenesis, biofilm formation and quorum sensing were up-regulated in pneumococci biofilms grown in the presence of UP. The HMEECs viability was significantly decreased (p < 0.05) and bacteria colonization was significantly elevated (p < 0.05) in co-treatment (UP + S. pneumoniae) when compared to single treatment. Similarly, increased apoptosis and ROS production were detected in HMEECs treated with UP + pneumococci. The microarray analysis of HMEECs revealed that the genes involve in apoptosis and cell death, inflammation, and immune response, were up-regulated in co-treatment and were unchanged or expressed in less fold in single treatments of UP or S. pneumoniae. The in vivo study showed an increased pneumococcal colonization of the nasopharynx in the presence of UP and a higher transition of bacteria to the middle ear and lungs in the presence of UP. The UP exposure elevated S. pneumoniae in vitro biofilm and colonization of HMEECs, and in vivo mouse nasopharyngeal colonization, and increased dissemination to mouse middle ear and lungs.

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Dataset Information

Math1, retinoic acid, and TNF-? synergistically promote the differentiation of mucous cells in mouse middle ear epithelial cells in vitro.

Publications

Math1, retinoic acid, and TNF-α synergistically promote the differentiation of mucous cells in mouse middle ear epithelial cells in vitro.

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