S1P受体激动剂FTY720预先给药对大鼠呼吸机相关性肺损伤的影响

Effects of FTY720 pretreatment on ventilator-induced lung injury in rats

摘要 目的观察1-磷酸鞘氨醇（S1P）受体激动剂芬戈莫德（fingolimod，FTY720）对大鼠呼吸机相关性肺损伤（VILI）的影响，探讨1-磷酸鞘氨醇1型受体在VILI中的作用。方法40只SD大鼠随机（随机数字法）分成4组：常规潮气量组（TV组）、大潮气量组（HV组）、大潮气量＋FTY720预处理组（HF组）、大潮气量＋FTY720＋S1P 1型受体拮抗剂w146预处理组（HFW组）。机械通气4 h后抽取股动脉血测氧分压（PaO2），取肺组织计算肺湿干质量比（W/D值）和肺泡通透性指数（PPI），测定支气管肺泡灌洗液（BALF）总蛋白、肿瘤坏死因子-α（TNF-α）、白细胞介素1β（IL-1β），流式细胞仪检测各组肺组织细胞凋亡率，光镜和电镜下观察肺组织病理学变化。采用SPSS 20.0统计软件，计量资料以均数±标准差（±s）表示，数据采用单因素方差分析，用LSD-t法进行组间两两比较，P〈0.05为差异具有统计学意义。结果与TV组比较，HV组PaO2 [（73.6± 8.9） vs.（50.5± 6.0）]降低，W/D值[（3.12± 0.27） vs.（5.12± 0.56）]和PPI[（0.08±0.03） vs.（0.30 ± 0.06）]升高、BALF中总蛋白[（5.8±2.1） vs.（15.4±5.6）]、TNF-α[（24.3±5.7） vs.（108.4±16.0）]、IL-1β [（90.6±14.1） vs.（338.5±44.3）]含量升高，肺组织细胞凋亡率[（10.6±2.9） vs.（48.5±6.7）]升高（P〈0.05）。与HV组相比，HF组PaO2[（50.5±6.0） vs.（65.9±10.3）]升高，W/D值[（5.12±0.56） vs.（3.85±0.37）]和PPI [（0.30±0.06） vs.（0.14±0.03）]降低，总蛋白[（15.4±5.6） vs.（8.9±2.5）]、BALF中TNF-α [（108.4±16.0） vs.（75.6±10.3）]、IL-1β [（338.5±44.3） vs.（188.9±33.8）]含量降低，肺组织细胞凋亡率降低[（48.5±6.7） vs.（25.6±5.3）]（P〈0.05）；HFW组PaO2[（50.5±6.0） vs.（59.7±7.8）]升高，W/D[（5.12±0.56） vs.（4.44±0.30）]、PPI值[（0.30±0.06） vs.（0.19±0.09）]及IL-1β含量[（338.5±44.3） vs.（246.8±24.6）]降低（P〈0.05），肺组织细胞凋亡率[（48.5±6.7） vs.（41.3±6.8）]、总蛋白[（15.4±5.6） vs.（10.4±2.7）]及TNF-α含量[（108.4±16.0） vs.（97.5±10.3）]与HV组差异无统计学意义（P〉0.05）。病理可见TV组肺组织损伤较轻微，HV组及HFW肺组织损伤较重，HF组肺组织损伤较HV组减轻。结论FTY720预先给药可减轻大鼠呼吸机相关性肺损伤，其可能通过激动S1P 1型受体，减轻肺组织炎症反应，抑制细胞凋亡发挥保护作用。

ObjectiveTo study the effects of FTY720 pretreatment on ventilator-induced lung injury （VILI） in rats in order to explore the role of sphingosine-1-phosphate receptor 1 （S1PR1）.MethodsForty healthy adult male SD rats weighing 300-350 g were randomly （randlom number）divided into 4 groups （n=10 each）： group CV （conventional tidal volume VT = 8 mL/kg）, group HV （high tidal volume VT= 40 mL/kg）, group HF and group HFW. The rats in group HF received intra-gastric administration of FTY720 10 mg·kg-1·d-1for 7 days, while additional dose of W146 （S1PR1 antagonist） 1 mg·kg-1·d-1 was administrated in group HFW before high tidal volume ventilation. After 4-hour mechanical ventilation, arterial blood samples were obtained for blood gas analysis before the animals were sacrificed. The lungs were harvested for histopathologic observation. Apoptosis rate in lung tissue was determined with flow cytometry. W/D lung weight ratio, pulmonary permeability index （PPI）, total protein, and TNF-α, IL-1β in bronchoaveolar lavage fluid （BALF） were measured. All data were analyzed by one-way analysis of variance （ANOVA）, The intergroup comparisons were analyzed by the least-significant-difference （LSD） test by using SPSS version 20.0 software. Differences were considered statistically significant if P〈0.05.ResultsCompared with group CV, the level of PaO2 [（73.6± 8.9） vs.（50.5± 6.0）] was decreased, the levels of W/D [（3.12± 0.27）vs. （5.12± 0.56）], PPI [（0.08±0.03）vs.（0.30 ± 0.06）], apoptosis rate [（10.6±2.9）vs.（48.5±6.7）], total protein [（5.8±2.1）vs.（15.4±5.6）] and TNF-α [（24.3±5.7） vs. （108.4±16.0）] and IL-1β [（90.6±14.1） vs.（338.5±44.3）] were increased in group HV （P〈0.05）. Compare with group HV, PaO2 [（50.5±6.0）vs.（65.9±10.3）] was increased, W/D [（5.12±0.56） vs. （3.85±0.37）], PPI [（0.30±0.06） vs. （0.14±0.03）], apoptosis rate [（48.5±6.7） vs.（25.6±5.3）], total protein [（15.4±5.6）vs.（8.9±2.5）], TNF-α [（108.4±16.0）vs.（75.6±10.3）] and IL-1β [（338.5±44.3） vs.（188.9±33.8）] in BALF were decreased in group HF （P〈0.05）. PaO2 [（50.5±6.0）vs.（59.7±7.8）] was higher, W/D [（5.12±0.56）vs.（4.44±0.30）], PPI [（0.30±0.06） vs. （0.19±0.09）] and IL-1β [（338.5±44.3）vs.（246.8±24.6）] levels were lower in group HFW than those in group HF There were no significant differences in apoptosis rate [（48.5±6.7）vs.（41.3±6.8）], total protein [（15.4±5.6）vs.（10.4±2.7）] and TNF-α level [（108.4±16.0）vs.（97.5±10.3）]between HFW group and HF group （P〉0.05）. Compare with group CV, The histopathologic damage of lung tissue was obvious in group HV and group HFW, it was attenuated by pretreatment with FTY720 in group HF.ConclusionsFTY720 pretreatment provides protective effects against ventilation-induced lung injury in rats, and S1PR1 may mediate the protection through reducing apoptosis rate and inflammatory reaction.