Biophysical function of pulmonary surfactant in liquid ventilation
Biophysical function of pulmonary surfactant in liquid ventilation
复制标题
肺表面活性物质在液体通气中的生物物理功能
DOI：
10.1016/j.bpj.2023.06.014
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发表时间：
2023
影响因子：
3.4
通讯作者：
Zuo, Yi Y.
中科院分区：
文献类型：
--
作者：
Li, Guangle;Xu, Xiaojie;Zuo, Yi Y.
液体通气是一种机械通气技术，其中整个或部分肺充满含氧全氟化碳（PFC）液体，而不是传统机械通气中的空气。尽管PFC具有许多理想的生物活性化学特性，可用于辅助液体呼吸，但对PFC的普遍误解是将其用作肺表面活性剂的替代品。由于PFC-水界面张力高（59 mN/m），肺表面活性物质在液体通气中不可或缺，以增加肺顺应性。然而，肺表面活性物质在液体通气中的生物物理功能仍不清楚。在这里，我们已经研究了吸附和动态表面活性的天然表面活性剂制剂，Infasurf，在PFC-水界面，使用约束滴表面活性测定法。约束液滴表面测定法能够模拟生理相关条件下液体通气的肺泡内微环境。结果发现，吸附到PFC-水界面的Infasurf在几秒钟内将PFC-水界面张力从59 mN/m降低到9 mN/m的平衡值。原子力显微镜显示，从头吸附后，Infasurf在PFC-水界面形成多层结构，平均厚度为10-20 nm，取决于吸附表面活性剂的浓度。结果发现，吸附的Infasurf膜能够调节PFC-水界面的界面张力在一个很窄的范围内，在1012和1011 mN/m之间，在动态压缩-膨胀循环，模仿液体通风。这些研究结果在理解肺表面活性物质膜在PFC-水界面的生理和生物物理功能方面具有新的意义，并可能为液体通气和液体呼吸技术的发展提供新的翻译见解。
Liquid ventilation is a mechanical ventilation technique in which the entire or part of the lung is filled with oxygenated perfluorocarbon (PFC) liquids rather than air in conventional mechanical ventilation. Despite its many ideal biophysicochemical properties for assisting liquid breathing, a general misconception about PFC is to use it as a replacement for pulmonary surfactant. Because of the high PFC-water interfacial tension (59 mN/m), pulmonary surfactant is indispensable in liquid ventilation to increase lung compliance. However, the biophysical function of pulmonary surfactant in liquid ventilation is still unknown. Here, we have studied the adsorption and dynamic surface activity of a natural surfactant preparation, Infasurf, at the PFC-water interface using constrained drop surfactometry. The constrained drop surfactometry is capable of simulating the intra-alveolar microenvironment of liquid ventilation under physiologically relevant conditions. It was found that Infasurf adsorbed to the PFC-water interface reduces the PFC-water interfacial tension from 59 mN/m to an equilibrium value of 9 mN/m within seconds. Atomic force microscopy revealed that after de novo adsorption, Infasurf forms multilayered structures at the PFC-water interface with an average thickness of 10–20 nm, depending on the adsorbing surfactant concentration. It was found that the adsorbed Infasurf film is capable of regulating the interfacial tension of the PFC-water interface within a narrow range, between ∼12 and ∼1 mN/m, during dynamic compression-expansion cycles that mimic liquid ventilation. These findings have novel implications in understanding the physiological and biophysical functions of the pulmonary surfactant film at the PFC-water interface, and may offer new translational insights into the development of liquid ventilation and liquid breathing techniques.