金水宝片对PM2.5致大鼠肺损伤的保护作用及其机制研究

Protective effect and mechanism of Jinshuibao Tablets on lung injury induced by PM2.5 in rats

目的观察金水宝片对PM2.5致肺损伤大鼠的影响并对其机制进行研究。方法SD雄性大鼠60只,随机分为对照组、模型组及金水宝片低、中、高剂量(0.225、0.450、0.900g/kg)组,每组12只。除对照组外,其余各组大鼠气管滴注PM2.5(10mg/kg)混悬液染毒,隔天1次,一周3次,连续4周,制备大鼠肺损伤模型。染毒结束后,除对照组、模型组外,其余各组ig给予相应金水宝片药液,1次/d,连续14d。观察各组大鼠一般状态;检查用力肺活量(FVC)、0.3秒用力呼出量(FEV0.3)、最大呼吸气流(PEF);ELISA法检测肺泡灌洗液(BALF)中白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)、嗜酸性粒细胞(EOS)及肺脏匀浆中转化生长因子-β1(TGF-β1)的水平;HE染色观察肺组织病理学改变;Western blotting检测肺组织中蛋白激酶B(Akt)、磷酸化-蛋白激酶B(p-Akt)、基质金属蛋白酶9(MMP-9)以及人α-平滑肌肌动蛋白(α-SMA)的表达。结果与模型组比较,中、高剂量金水宝片均能提高肺损伤大鼠的FVC、FEV0.3、PEF、FEV0.3/FVC(P<0.01),降低IL-6、TNF-α、EOS、TGF-β1水平(P<0.05、0.01),显著改善大鼠肺组织病理学变化,降低大鼠肺脏中p-Akt、MMP-9、α-SMA表达(P<0.05、0.01)。结论金水宝片对PM2.5导致大鼠肺损伤具有明显治疗作用,其作用机制可能与金水宝片通过PI3K/Akt信号通路减少炎症反应,延缓纤维化进展有关。

Objective To observe the protective effect of Jinshuibao Tablets on lung injury of rats induced by particulate matter (PM2.5), and investigate its mechanism. Methods A total of 60 healthy adult male SD rats were randomly divided into five groups, the control group, the model group and Jinshuibao Tablets (low, moderate and high-dose) groups that were administered with drug through gavage at the doses of 0.225, 0.450, and 0.900 g/kg body weight (BW), with twelve rats in each group. The blank group was treated with normal saline by intratracheal instillation, the other groups were exposed by intratracheal instillation of PM2.5 saline suspension with the dose of 10 mg/kg BW, repeated three times per week for four weeks. At the end of the exposure, the rats in each group except control and model groups were given Jinshuibao Tablets suspension with the doses of 0.225, 0.450, and 0.900 g/kg BW, repeated once a day for 14 d. The peak expiratory flow (PEF), forced vital capacity (FVC) and volume expired in first 30 ms of fast expiration (FEV0.3) were measured, and the ratio of FEV0.3/FVC was calculated. The collected bronchoalveolar lavage fluid (BALF) was analyzed for the levels of interleukin-6 (IL-6), necrosis factor alpha (TNF-α), and eosinophils (EOS). The level of transforming growth factor-β1 (TGF-β1) was analyzed in lung homogenate. The histological changes of lung were observed. The protein kinase B (Akt), phosphorylation-protein kinase B (p-Akt),α smooth muscle actin (α-SMA) and matrix metallopeptidase 9 (MMP-9) of lung were assayed by western blotting. Results Compared to the model group, the PEF, FVC, FEV0.3 and FEV0.3/FVC of the moderate and high-dose groups were significantly increased (P < 0.01), the levels of IL-6, TNF-α, EOS, TGF-β1 in moderate and high-dose groups were significantly decreased (P < 0.05, P < 0.01). The pathological changes of the lungs in moderate and high-dose groups treated with Jinshuibao Tablets were obviously relieved. The expression of p-Akt,α-SMA, and MMP-9 in the moderate and high-dose groups were obviously reduced (P < 0.05, P < 0.01). Conclusion Jinshuibao Tablets has obvious antagonistic effect on PM2.5-induced damage of rat respiratory system, and its regulation mechanism may be related to the reduction of inflammatory reactions and the delay of fibrosis progression through the PI3K/Akt signaling pathway.