Olivera Dorian S, Hoard-Fruchey Heidi, Sciuto Alfred M
a Analytical Toxicology Division, U.S. Army Medical Research Institute of Chemical Defense , Aberdeen Proving Ground, MD , USA.
Toxicol Mech Methods. 2017 Jan;27(1):45-51. doi: 10.1080/15376516.2016.1243183. Epub 2016 Oct 28.
Therapeutic development against exposure to toxic gases is hindered by the lack of appropriate models to evaluate candidate compounds prior to animal efficacy studies. In this study, an in vitro, air-liquid interface exposure model has been tested to examine its potential application for screening treatments for phosgene (carbonyl chloride)-induced pulmonary injury. Epithelial cultures on Transwell inserts, combined with a Vitrocell exposure apparatus, provided a physiologically relevant exposure environment. Differentiated human bronchial epithelial (16HBE) cultures were exposed for 8 min to phosgene ranging from 0 to 64 ppm and assessed for changes in transepithelial electrical resistance (TEER, epithelial barrier integrity), cellular viability (XTT) and post-exposure (PE) cellular metabolic energy status. Exposure to phosgene concentrations ≥8 ppm caused dose-dependent and significant decreases in TEER and XTT which did not recover within 24-h PE. In addition, at 64 ppm the rate of oxidative glutamine metabolism was significantly inhibited at 6 and 24 h after exposure. Glycolytic activities (glucose utilization and lactate production) were also inhibited, but to a lesser extent. Decreased glycolytic function can translate to insufficient energy sources to counteract barrier function failure. Consistent and sensitive markers of phosgene exposure were TEER, cell viability and decreased metabolism. As such, we have assessed an appropriate in vitro model of phosgene inhalation that produced quantifiable alterations in markers of lung cell metabolism and injury in human airway epithelial cells. Data indicate the suitability of this model for testing classes of anti-edemagenic compounds such as corticosteroids or phosphodiesterase inhibitors for evaluating phosgene therapeutics.
在动物功效研究之前，由于缺乏合适的模型来评估候选化合物，针对接触有毒气体的治疗性开发受到阻碍。在本研究中，对一种体外气液界面暴露模型进行了测试，以检验其在筛选光气（碳酰氯）诱导的肺损伤治疗方法方面的潜在应用。Transwell小室上的上皮细胞培养物与Vitrocell暴露装置相结合，提供了一个生理相关的暴露环境。将分化的人支气管上皮（16HBE）细胞培养物暴露于0至64 ppm的光气中持续8分钟，并评估跨上皮电阻（TEER，上皮屏障完整性）、细胞活力（XTT）以及暴露后（PE）细胞代谢能量状态的变化。暴露于≥8 ppm的光气浓度会导致TEER和XTT呈剂量依赖性显著下降，且在暴露后24小时内未恢复。此外，在64 ppm时，暴露后6小时和24小时氧化型谷氨酰胺代谢速率显著受到抑制。糖酵解活性（葡萄糖利用和乳酸产生）也受到抑制，但程度较轻。糖酵解功能下降可能导致能量来源不足，无法抵消屏障功能衰竭。光气暴露的一致且敏感的标志物是TEER、细胞活力和代谢下降。因此，我们评估了一种合适的光气吸入体外模型，该模型在人呼吸道上皮细胞的肺细胞代谢和损伤标志物中产生了可量化的改变。数据表明该模型适用于测试抗水肿化合物类别，如皮质类固醇或磷酸二酯酶抑制剂，以评估光气治疗方法。
