Proteogenomics Research Institute for Systems Medicine (PRISM), La Jolla, California, USA.
Pharmacology. 2024;109(1):22-33. doi: 10.1159/000534329. Epub 2023 Nov 17.
We investigated the potential of LPS (10-300 µg/rat) administered intratracheally (i.t.) to induce reproducible features of acute lung injury (ALI) and compared the pharmacological efficacy of anti-inflammatory glucocorticoids and antifibrotic drugs to reduce the disease. Additionally, we studied the time-dependent progression of ALI in this LPS rat model.
We conducted (1) dose effect studies of LPS administered i.t. at 10, 30, 100, and 300 μg/rat on ALI at 4 h timepoint; (2) pharmacological interventions using i.t. fluticasone (100 and 300 μg/rat), i.t. pirfenidone (4,000 μg/rat), and peroral dexamethasone (1 mg/kg) at 4 h timepoint; (3) kinetic studies at 0, 2, 4, 6, 8, 10, and 24 h post-LPS challenge. Phenotype or pharmacological efficacy was assessed using predetermined ALI features such as pulmonary inflammation, edema, and inflammatory mediators.
All LPS doses induced a similar increase of inflammation, edema, and inflammatory mediators, e.g., IL6, IL1β, TNFα, and CINC-1. In pharmacological intervention studies, we showed fluticasone and dexamethasone ameliorated ALI by inhibiting inflammation (>60-80%), edema (>70-100%), and the increase of cytokines IL6, IL1β, and TNFα (≥70-90%). We also noticed some inhibition of CINC-1 (25-35%) and TIMP1 (57%) increase with fluticasone and dexamethasone. Conversely, pirfenidone failed to inhibit inflammation, edema, and mediators of inflammation. Last, in ALI kinetic studies, we observed progressive pulmonary inflammation and TIMP1 levels, which peaked at 6 h and remained elevated up to 24 h. Progressive pulmonary edema started between 2 and 4 h and was sustained at later timepoints. On average, levels of IL6 (peak at 6-8 h), IL1β (peak at 2-10 h), TNFα (peak at 2 h), CINC-1 (peak at 2-6 h), and TGFβ1 (peak at 8 h) were elevated between 2 and 10 h and declined toward 24 h post-LPS challenge.
Our data show that 10 μg/rat LPS achieved a robust, profound, and reproducible experimental ALI phenotype. Glucocorticoids ameliorated key ALI features at the 4-h timepoint, but the antifibrotic pirfenidone failed. Progressive inflammation and sustained pulmonary edema were present up to 24 h, whereas levels of inflammatory mediators were dynamic during ALI progression. This study's data might be helpful in designing appropriate experiments to test the potential of new therapeutics to cure ALI.
我们研究了经气管内（i.t.）给予脂多糖（LPS）（10-300μg/大鼠）以诱导急性肺损伤（ALI）的重现特征，并比较了抗炎糖皮质激素和抗纤维化药物的药效学，以降低疾病的严重程度。此外，我们研究了这种 LPS 大鼠模型中 ALI 的时间依赖性进展。
我们进行了（1）i.t.给予 LPS（10、30、100 和 300μg/大鼠）在 4 小时时间点对 ALI 的剂量效应研究；（2）在 4 小时时间点使用 i.t.氟替卡松（100 和 300μg/大鼠）、i.t.吡非尼酮（4000μg/大鼠）和口服地塞米松（1mg/kg）进行药理学干预；（3）在 LPS 挑战后 0、2、4、6、8、10 和 24 小时进行动力学研究。使用预定的 ALI 特征，如肺炎症、水肿和炎症介质，评估表型或药效学。
所有 LPS 剂量均诱导相似程度的炎症、水肿和炎症介质增加，例如 IL6、IL1β、TNFα 和 CINC-1。在药理学干预研究中，我们发现氟替卡松和地塞米松通过抑制炎症（>60-80%）、水肿（>70-100%）和细胞因子 IL6、IL1β 和 TNFα 的增加（≥70-90%）来改善 ALI。我们还注意到氟替卡松和地塞米松对 CINC-1（25-35%）和 TIMP1（57%）增加的一些抑制作用。相反，吡非尼酮未能抑制炎症、水肿和炎症介质。最后，在 ALI 动力学研究中，我们观察到进行性肺炎症和 TIMP1 水平增加，在 6 小时达到峰值，并持续至 24 小时。进行性肺水肿在 2 至 4 小时之间开始，并在以后的时间点持续存在。平均而言，IL6（6-8 小时达到峰值）、IL1β（2-10 小时达到峰值）、TNFα（2 小时达到峰值）、CINC-1（2-6 小时达到峰值）和 TGFβ1（8 小时达到峰值）在 2 至 10 小时之间升高，并在 LPS 挑战后 24 小时下降。
我们的数据表明，10μg/大鼠 LPS 实现了强大、深刻和可重现的实验性 ALI 表型。糖皮质激素在 4 小时时间点改善了关键的 ALI 特征，但抗纤维化的吡非尼酮未能改善。进行性炎症和持续的肺水肿持续至 24 小时，而炎症介质水平在 ALI 进展过程中呈动态变化。本研究的数据可能有助于设计适当的实验，以测试新疗法治疗 ALI 的潜力。
