背景:在呼吸机诱导的肺损伤(VILI)中,巨噬细胞被激活,伴有巨噬细胞焦亡。瑞咪唑仑(Re)在抑制巨噬细胞活化中起作用。在这项研究中,我们旨在探讨Re在VILI中的作用机制。
方法:使用C57BL/6小鼠创建VILI模型(20mL/kg机械通气)。从支气管肺泡灌洗液(BALF)中分离肺泡巨噬细胞,并进行机械拉伸以模拟体外机械通气。VILI模型小鼠用Re(16mg/kg)治疗以评估肺泡结构,湿/干(W/D)重量比,内皮屏障抗原(EBA)通透性指数,BALF蛋白质含量,炎症因子,巨噬细胞焦亡,焦亡相关因素,和转运蛋白(TSPO)水平使用了一系列的生物学实验。通过拯救实验确定Re是否通过调节TSPO减轻巨噬细胞的焦亡。
结果:重新缓解了VILI,VILI期间肺组织异常形态的改善和肺W/D重量比的降低证明,肺EBA通透性指数,和BALF蛋白质含量。通过下调炎症因子(髓过氧化物酶,malondialchehyche,8-羟基-2脱氧鸟苷,白细胞介素-6,肿瘤坏死因子-α,巨噬细胞炎性蛋白-2,白细胞介素-1β,和白细胞介素18),和焦亡因子(裂解气体蛋白D(GSDMD)/GSDMD值,NOD样受体热蛋白结构域相关蛋白3(NLRP3),和caspase-1)。在巨噬细胞中再激活TSPO。TSPO过表达挽救了细胞拉伸抑制的巨噬细胞活力和细胞拉伸诱导的巨噬细胞焦亡。
结论:Re通过激活TSPO抑制巨噬细胞焦亡减轻VILI。
BACKGROUND: Macrophages are activated in ventilator-induced lung injury (VILI), accompanied by macrophage pyroptosis. Remimazolam (Re) plays a role in inhibiting macrophage activation. In this study, we aimed to investigate the mechanism of Re in VILI.
METHODS: A VILI model (20 mL/kg mechanical ventilation) was created using C57BL/6 mice. Alveolar macrophages were isolated from bronchoalveolar lavage fluid (BALF) and received mechanical stretching to simulate the mechanical ventilation in vitro. VILI model mice were treated with Re (16 mg/kg) to assess the alveolar structure, wet/dry (W/D) weight ratio, endothelial barrier antigen (EBA) permeability index, BALF protein content, inflammatory factors, macrophage pyroptosis, pyroptosis-related factors, and translocator protein (TSPO) level using a series of biological experiments. Whether Re alleviated macrophage pyroptosis by regulating TSPO was determined by rescue experiments.
RESULTS: Re alleviated VILI, as evidenced by improvement of abnormal morphology of lung tissues during VILI and decreases in the lung W/D weight ratio, lung EBA permeability index, and BALF protein content. Re attenuated pulmonary inflammation and macrophage pyroptosis during VILI via down-regulation of inflammatory factors (myeloperoxidase, malondialchehyche, 8-hydroxy-2 deoxyguanosine, interleukin-6, tumor necrosis factor-α, macrophage inflammatory protein-2, interleukin-1β, and interleukin-18), and pyroptosis factors (cleaved gasdermin D (GSDMD)/GSDMD value, NOD-like receptor thermal protein domain associated protein 3 (NLRP3), and caspase-1). Re activated TSPO in macrophages. TSPO overexpression rescued the cell stretch-inhibited macrophage viability and cell stretch-induced macrophage pyroptosis.
CONCLUSIONS: Re alleviates VILI by activating TSPO to inhibit macrophage pyroptosis.