González Claudia, Droguett Karla, Rios Mariana, Cohen Noam A, Villalón Manuel
Department of Otorhinolaryngology, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile.
Department of Physiology, Faculty of Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile.
Biomed Res Int. 2016;2016:3628501. doi: 10.1155/2016/3628501. Epub 2016 Nov 29.
In airway epithelium, mucociliary clearance (MCC) velocity depends on the ciliary beat frequency (CBF), and it is affected by mucus viscoelastic properties. Local inflammation induces secretion of cytokines (TNF) that can alter mucus viscosity; however airway ciliated cells have an autoregulatory mechanism to prevent the collapse of CBF in response to increase in mucus viscosity, mechanism that is associated with an increment in intracellular Ca level ([Ca]). We studied the effect of TNF on the autoregulatory mechanism that regulates CBF in response to increased viscosity using dextran solutions, in ciliated cells cultured from human pediatric epithelial adenoid tissue. Cultures were treated with TNF, before and after the viscous load was changed. TNF treatment produced a significantly larger decrease in CBF in cultures exposed to dextran. Furthermore, an increment in [Ca] was observed, which was significantly larger after TNF treatment. In conclusion, although TNF has deleterious effects on ciliated cells in response to maintaining CBF after increasing viscous loading, it has a positive effect, since increasing [Ca] may prevent the MCC collapse. These findings suggest that augmented levels of TNF associated with an inflammatory response of the nasopharyngeal epithelium may have dual effects that contribute to maintaining the effectiveness of MCC in the upper airways.
在气道上皮中，黏液纤毛清除（MCC）速度取决于纤毛摆动频率（CBF），并且会受到黏液黏弹性特性的影响。局部炎症会诱导细胞因子（TNF）分泌，从而改变黏液黏度；然而，气道纤毛细胞具有一种自动调节机制，可防止因黏液黏度增加而导致的CBF下降，该机制与细胞内钙水平（[Ca]）升高有关。我们使用葡聚糖溶液，在从人类小儿上皮腺样组织培养的纤毛细胞中，研究了TNF对响应黏度增加而调节CBF的自动调节机制的影响。在改变黏性负荷之前和之后，对培养物进行TNF处理。在暴露于葡聚糖的培养物中，TNF处理使CBF显著降低。此外，观察到[Ca]升高，且在TNF处理后显著更大。总之，尽管TNF在黏性负荷增加后对维持CBF的纤毛细胞有有害影响，但它也有积极作用，因为升高[Ca]可能会防止MCC崩溃。这些发现表明，与鼻咽上皮炎症反应相关的TNF水平升高可能具有双重作用，有助于维持上呼吸道MCC的有效性。
