黄芪甲苷对失血性休克后大鼠肺损伤及炎性反应的影响

Effects of astragaloside Ⅳ on lung injury and inflammation after hemorrhagic shock and resuscitation in rats

目的观察黄芪甲苷对失血性休克后大鼠肺损伤及炎性反应的影响。方法将24只雄性SD大鼠随机分为3组（n=8）：假手术组（Sham组）、失血性休克-复苏组（HS—R组）、黄芪甲苷＋失血性休克．复苏组（AGS＋HS—R组）。Sham组接受所有外科操作但不行股动脉抽血和液体复苏；HS—R组仅制备失血性休克．复苏模型；AGS＋HS-R组制备失血性休克．复苏模型，并于液体复苏开始时腹腔注射20mg／kg黄芪甲苷。取肺组织，观察肺病理变化并检测髓过氧化物酶（MPO）活性。Westernblot法检测浆蛋白高迁移率族蛋白B1（HMGB1）、总蛋白Toll样因子受体4（TLR4）及磷酸化p38丝裂原活化蛋白激酶（p-p38MAPK）蛋白表达水平。酶联免疫吸附试验（ELISA）法检测肺组织肿瘤坏死因子-α（TNF-α）和白细胞介素（IL）-1β蛋白表达水平。结果AGS＋HS—R组肺组织镜下炎性细胞浸润减少，肺间质增厚及肺泡塌陷表现亦明显改善。AGS＋HS-R组[（5．2±0．9）U／g]肺组织MPO活性较HS—R组[（8．2±1．6）U／g]下降36．6％（P〈0．01）。AGS＋HS-R组肺组织浆蛋白HMGB1、总蛋白TLR4及p-038MAPK蛋白表达水平较HS-R组分别降低24．9％、27．5％、23．7％（P〈0．01或P〈0．05）。AGS＋HS-R组肺组织TNF—α和IL-1β蛋白表达水平较HS—R组分别降低66．3％、44．3％（P〈0．01）。结论黄芪甲苷可缓解失血性休克复苏后大鼠肺损伤及炎性反应，其机制与抑制HMGB1／TLR4信号通路相关。

Objective To investigate the effects of astragaloside Ⅳ on lung injury and inflammation after hemorrhagic shock and resuscitation in rats. Methods Twenty - four male Sprague Dawley rats were randomly divided in 3 groups, including Sham group, hemorrhagic shock - resuscitation group （ HS - R group） and astragaloside Ⅳ ＋ hemorrhagic shock - resuscitation group （ ACTS ＋ HS - R group）. Hemorrhagic shock was induced by blood drawing from the femoral artery, and the resuscitation was performed by infusion of shed blood and two - fold volume saline. The operations for Sham group were the same with HS - R group, except that the blood drawing and fluid resuscitation were not performed. The rats in ACTS ± HS - R group were subjected to hemorrhagic shock, and 20 mg/kg of astragaloside Ⅳ was intraperitoneally injected at the onset of resuscitation. Two h after resuscitation, histological changes were observed under light microscope, and myeloperoxidase （MPO） activities were determined with a commercial kit. The protein levels of cytoplasmic high mobility group protein B1 （HMGB1） as well as Toll- like receptor 4 （TLR4） and phos- pho-p38 mitogen activated protein kinase （p- p38MAPK） protein expression levels were detected by Western blotting. The protein levels of eytokines such as tumor necrosis factor-ct （TNF- α） and interleu- kin （IL） - 1β were examined by enzyme linked immunosorbent assay （ELISA）. Results Histological results showed that the lung injury after hemorrhagic shock and resuscitation was attenuated by the treatment of astragaloside Ⅳ. As compared with HS - R group [ （8.2 ± 1.6） U/g], the treatment of astragaloside Ⅳ [ （5.2±0. 9） U/g] decreased MPO activities by 36. 6% （P 〈 0. 01 ）. In addition, the astragaloside Ⅳ treatment also down - regulated the expression levels of cytoplasmic HMGB1 as well as TLR4 and p - p38MAPK by 24. 9% , 27.5% , and 23.7% , respectively （ P 〈 0. 01 or P 〈 0. 05）. The results of ELISA suggested that the lung protein levels of TNF - α, and IL - 1β after hemorrhagic shock and resusci- tation were decreased by 66. 3%, and 44. 3% respectively （ P 〈 0. 01 ）. Conclusion Astragaloside Ⅳmight attenuate the lung injury after hemorrhagic shock and resuscitation via inhibition of HMGB1/TLR4 signaling.