黄芪提取物对急性肺栓塞兔模型肺组织p38-MAPK通路表达的影响

Effects of Astragalus Extract on the Expression of p38-MAPK Pathway in Pulmonary Tissue of Rabbit Model with Acute Pulmonary Embolism

目的探究黄芪提取物对急性肺栓塞兔模型肺组织p38-MAPK通路表达的影响。方法取75只雄性日本大耳白兔,采用随机数字表法分为:空白对照组,模型组,低、中、高剂量黄芪提取物组,每组15只。除空白对照组外各组采用自体血栓回输法建立急性肺栓塞模型,低、中、高剂量黄芪提取物组分别腹腔注射20 g/kg、40 g/kg和60 g/kg的黄芪提取物,1次/d,连续注射1周。分别于造模前和治疗后检测各组大耳兔中心静脉压(central venous pressure,CVP)及肺动脉平均压(pulmonary arterial mean pressure,PAMP);采用酶联免疫吸附法(enzyme linked immunosorbent assay,ELISA)和实时聚合酶链式反应(real-time polymerase chain reaction,RT-PCR)检测各组血清及肺组织血管内皮生长因子(vascular endothelial growth factor,VEGF)和碱性成纤维生长因子(basic fibroblast growth factor,b FGF)水平;采用ELASA法检测各组血清肿瘤坏死因子-α(tumor necrosis factorα,TNF-α)、白细胞介素-4(interleukin-4,IL-4)和白细胞介素-1β(interleukin-1β,IL-1β)含量水平;苏木精-伊红(hematoxylin-eosin,HE)染色观察大耳白兔肺组织病理学变化;采用蛋白质印迹法检测p-p38 MAPK蛋白表达水平。结果HE染色观察发现,模型组大耳白兔出现明显的血栓,且炎性细胞浸润较多,肺小静脉扩张;黄芪提取物各组无血栓且炎性浸润显著改善,肺小静脉基本无扩张。各组造模前肺血流动力学指标差异均无统计学意义(P>0.05);与空白对照组比较,模型组CVP,PAMP,血清VEGF、b FGF和肺组织VEGF mRNA、b FGF mRNA,TNF-α、p-p38 MAPK蛋白相对表达均显著升高(P<0.05),血清IL-4、IL-1β水平均显著降低(P<0.05);与模型组比较,黄芪提取物各组CVP、PAMP、TNF-α和p-p38-MAPK蛋白表达显著降低(P<0.05),且随着黄芪提取物剂量增加而降低(P<0.05);血清VEGF、b FGF和肺组织VEGF mRNA、b FGF mRNA、IL-4、IL-1β显著升高(P<0.05),且随着黄芪提取物剂量增加而升高(P<0.05)。结论黄芪提取物可以通过抑制p38-MAPK通路减少下游炎症相关因子的表达达到治疗急性肺栓塞的效果。

Objective To explore the effects of Astragalus extract(AE)on the expression of p38-MAPK pathway in pulmonary tissue of rabbit model with acute pulmonary thromboembolism(PTE).Methods Seventy-five male Japanese white rabbits were enrolled.They were divided into blank control group,model group,low-dose,medium-dose and high-dose AE groups by random number table method,15 cases in each group.Except for blank control group,the acute PTE model was established by autologous blood transfusion in the other groups.The low-dose,medium-dose and high-dose AE groups were intraperitoneally injected with 20 g/kg,40 g/kg and 60 g/kg AE(1 time/d,continuous treatment for1 week),respectively.Before modeling and after treatment,central venous pressure(CVP)and pulmonary arterial mean pressure(PAMP)in each group were detected.The levels of vascular endothelial growth factor(VEGF)and basic fibroblast growth factor(b FGF)in serum and pulmonary tissues of each group were detected by enzyme-linked immunosorbent assay(ELASA)and real-time polymerase chain reaction(RT-PCR).The levels of serum tumor necrosis factor-α(TNF-α),interleukin-4(IL-4)and interleukin-1β(IL-1β)were detected by ELASA.The pathological changes of pulmonary tissues were observed by HE staining.The expression level of p-p38 MAPK protein was detected by Western blot.Results HE staining observation showed that the big-eared white rabbits in the model group had obvious thrombosis,with more inflammatory cell infiltration and dilated pulmonary venules;each group using astragalus extract had no thrombosis and the inflammatory infiltration was significantly improved,and the pulmonary venules were basically absent.There was no statistically significant difference in lung hemodynamic indicators in each group before modeling(P>0.05);compared with the blank control group,CVP,PAMP,serum VEGF,b FGF and lung tissue VEGF mRNA,b FGF mRNA,TNF-The relative expression ofαand p-p38 MAPK proteins were significantly increased(P<0.05),and serum IL-4 and IL-1βlevels were significantly reduced(P<0.05);compared with the model group,the CVP,The protein expression of PAMP,TNF-αand p-p38-MAPK decreased significantly(P<0.05),and decreased with the increase of the dose of astragalus extract(P<0.05);serum VEGF,b FGF and lung tissue VEGF mRNA,b FGF mRNA,IL-4,IL-1βincreased significantly(P<0.05),and increased with the increase in the dose of Astragalus extract(P<0.05).Conclusion AE can reduce the expression of downstream inflammation-related factors by inhibiting p38-MAPK pathway to achieve treatment effect on acute PTE.