丹参提取物调控Nrf2/ARE通路改善重症急性胰腺炎大鼠肺损伤的作用机制

Mechanism of Salvia miltiorrhiza extract regulating Nrf2/ARE pathway in improving lung injury in rats with severe acute pancreatitis

目的探讨丹参提取物调控核因子E2相关因子2/抗氧化反应元件(Nrf2/ARE)通路改善重症急性胰腺炎(SAP)大鼠肺损伤的作用机制。方法以逆行胆胰管注射5%牛磺胆酸钠(1 ml/kg)法建立SAP肺损伤大鼠模型,随机分为模型组、丹参提取物(1.5 g/kg)组、ML385(Nrf2/ARE通路抑制剂,剂量:20 mg/kg)组和丹参提取物(1.5 g/kg)+ML385(20 mg/kg)组。测量腹水量,计算W/D比值(W/D=湿重/干重);以苏木精-伊红(HE)染色检测各组大鼠肺组织病理,并进行Holfbauer评分;以全自动血气分析检测仪检测动脉血气指标;试剂盒检测血清中超氧化物歧化酶(SOD)、丙二醛(MDA)水平和肺组织活性氧(ROS)水平,以蛋白免疫印迹法(Western blot)检测Nrf2蛋白表达。结果与对照组比较,模型组大鼠肺组织出现肺泡壁毛细血管明显扩张变厚,肺泡间隔变大,肺间质充血、水肿、炎性细胞大量浸润等病理损伤症状,腹水量、肺组织ROS水平、W/D及Holfbauer评分、PaCO2、血清MDA水平显著升高(P<0.05),PaO2、氧合指数(OI)、血清SOD水平显著降低(P<0.05)。与模型组比较,丹参提取物组大鼠上述病理损伤症状减轻,腹水量、肺组织ROS水平、W/D及Holfbauer评分、PaCO2、血清MDA水平降低(P<0.05),PaO2、OI、血清SOD水平、肺组织Nrf2蛋白表达升高(P<0.05);与模型组比较,ML385组大鼠上述病理损伤症状加重,腹水量、肺组织ROS水平、W/D及Holfbauer评分、PaCO2、血清MDA水平升高(P<0.05),PaO2、OI、血清SOD水平、肺组织Nrf2蛋白表达降低(P<0.05)。与丹参提取物组比较,丹参提取物+ML385组大鼠上述病理损伤症状加重,腹水量、肺组织ROS水平、W/D及Holfbauer评分、PaCO2、血清MDA水平升高(P<0.05),PaO2、OI、血清SOD水平、肺组织Nrf2蛋白表达降低(P<0.05)。结论丹参提取物可通过激活Nrf2/ARE信号保护急性胰腺炎肺损伤大鼠的肺组织。

Objective To investigate the mechanism of Salvia miltiorrhiza extract regulating nuclear factor-E2-related factor 2/antioxidant response element(Nrf2/ARE)pathway in improving lung injury in rats with severe acute pancreatitis(SAP).Methods The SAP lung injury rat model was established by retrograde injection of 5%sodium taurocholate(1 ml/kg)into biliopancreatic duct.The rats were randomly divided into model group,Salvia miltiorrhiza extract(1.5 g/kg)group,ML385(Nrf2/ARE pathway inhibitor,dose:20 mg/kg)group and Salvia miltiorrhiza extract+ML385 group(dose:1.5 g/kg,20 mg/kg).The ascites volume was measured,and W/D ratio(W/D=wet weight/dry weight)was calculated.Pathological symptoms of lung tissues were detected by hematoxylin-eosin(HE)staining,and Holfbauer score was performed.Arterial blood gas indexes were detected by automatic blood gas analyzer.Serum superoxide dismutase(SOD),malonaldehyde(MDA)levels and lung reactive oxygen species(ROS)levels were detected by enzyme-linked immunosorbent assay(ELISA)kit.And the expression of Nr£2 protein was detected by Western blot.Results Compared with the control group,the lung tissue of the model group showed obvious dilation and thickening of alveolar wall capillaries,enlargement of alveolar septum,hyperemia,edema and infiltration of inflammatory cells in the pulmonary interstitium.The ascites volume,ROS level in lung tissue,W/D and Holfbauer score,arterialpartial pressure of carbon dioxide(PaC02)and ser­um MDA levels were significantly increased(P<0.05),while arterial partial pressure of oxygen(PaO2),oxygenation index(OI)and serum SOD levels were significantly decreased(P<0.05).Compared with the model group,the above pathological damage symptoms were alleviated in Salvia miltiorrhiza extract group,the ascites volume,ROS level of lung tissue,W/D,Holfbauer score,PaCO2 and serum MDA level were decreased(P<0.05);while the PaO2,OI,serum SOD level and Nr£2 protein expression in lung tissue were increased(P<0.05).Compared with the model group,the above pathological damage symptoms were aggravated in ML385 group,and the ascites volume,ROS level of lung tissue,W/D,Holfbauer score,PaCO2 and serum MDA level were significantly increased(P<0.05),while Pa02,OI,serum SOD level,and Nr£2 protein expression in lung tissue were significantly decreased(P V 0.05).Compared with the Sal­via miltiorrhiza extract group,the above pathological damage symptoms were aggravated in the Salvia miltior-rhiza extract+ML385 group;the ascites volume,ROS level in lung tissue,W/D,Holfbauer score,PaC02 and MDA level in serum were increased(P<0.05),while Pa02,OI,SOD level in serum and Nr£2 protein expression in lung tissue were decreased(P<0.05).Conclusions Salvia miltiorrhiza extract can protect lung tissue of rats with acute pancreatitis and lung injury by activating NH2/ARE signal.