辐射防护中药复方归芪益元膏对^(12)C^(6+)束辐射右肺致左肺旁效应损伤大鼠保护机制

Guiqi Yiyuan Ointment protects rat left lung from bystander effect of right lung injury induced by ^(12)C^(6+)beam

观察辐射防护中药复方归芪益元膏(Guiqi Yiyuan Ointment,GQYY)对^(12)C^(6+)束辐射右肺致左肺旁效应损伤大鼠的作用,从NOD样受体蛋白3(NOD-like receptor protein 3,NLRP3)/凋亡相关斑点样蛋白(apoptosis-associated speck-like protein containing a CARD,ASC)/含半胱氨酸的天冬氨酸蛋白水解酶-1(cysteinyl aspartate specific proteinase-1,caspase-1)通路探讨其机制。Wistar大鼠随机分成7组,分别为空白组,模型组,抑制剂组[200 mg·kg^(-1),N-乙酰半胱氨酸(N-acetylcysteine,NAC)],西药组[140 mg·kg^(-1),氨磷汀(amifostine,AMI)],中药高、中、低剂量组(灌胃GQYY 4.8、2.4、1.2 g·kg^(-1))。4 Gy ^(12)C^(6+)束一次性右肺(铅板屏蔽其余部位)照射建立辐射旁效应损伤模型。观察各组大鼠双肺组织病理形态学变化,肺组织活性氧(reative oxygen species,ROS)水平及血清超氧化物岐化酶(superoxide dismutase,SOD)、脂质过氧化产物丙二醛(malondialdehyde,MDA)含量,NLRP3、ASC、caspase-1、磷酸化核转录因子-κB p65(p-NF-κB p65)/核转录因子-κB p65(NF-κB p65)蛋白及mRNA表达。与空白组比较,模型组肺泡壁明显增厚、水肿,肺泡腔明显变窄,肺泡壁和肺泡腔充满红细胞、大量炎性细胞浸润;左右肺组织ROS水平均升高,血清MDA水平升高,SOD水平降低;NLRP3、ASC、caspase-1、p-NF-κB p65/NF-κB p65 mRNA及蛋白表达量均升高;与模型组比较,各给药组肺脏组织炎性细胞浸润明显减少,其中抑制剂组和西药组肺泡腔体积增大,间质变薄,整体炎性改变程度降低,中药高、中剂量组存在少量肺泡壁断裂,中药低剂量组炎性细胞浸润较模型组也有所减轻;各给药组左、右肺ROS水平均降低,血清MDA水平下降,SOD水平上升;各给药组NLRP3、ASC、caspase-1、p-NF-κB p65/NF-κB p65 mRNA及蛋白表达均有不同程度下降。GQYY能有效减轻辐射及旁效应损伤作用,其机制可能与ROS介导的NLRP3炎症小体活化相关。

This study observed the effects of Guiqi Yiyuan Ointment(GQYY)on the left lung subjecting to bystander effect of right lung injury induced by ^(12)C^(6+)beam in rats and decipher the underlying mechanism from NOD-like receptor protein 3(NLRP3)/apoptosis-associated speck-like protein containing a CARD(ASC)/cysteinyl aspartate specific proteinase-1(caspase-1)pathway.Wistar rats were randomized into 7 groups:blank,model,inhibitor[200 mg·kg^(-1),N-acetylcysteine(NAC)],western drug[140 mg·kg^(-1) amifostine(AMI)],and high-,medium-,and low-dose(4.8,2.4,and 1.2 g·kg^(-1),respectively)GQYY groups.The model of bystander effect damage was established by 4 Gy ^(12)C^(6+)beam irradiation of the right lung(with the other part shielded by a lead plate).The pathological changes in the lung tissue,the level of reactive oxygen species(ROS)in the lung tissue,and the levels of superoxide dismutase(SOD)and malondialdehyde(MDA)in the serum were observed and measured in each group.Furthermore,the mRNA and protein levels of NLRP3,ASC,caspase-1,and phosphorylated nuclear factor-κB p65(p-NF-κB p65)/nuclear factor-κB p65(NF-κB p65)were determined.Compared with the blank group,the model group showed thickened alveolar wall,narrowed alveolar cavity,and presence of massive red blood cells and inflammatory infiltration in the alveolar wall and alveolar cavity.In addition,the model group showed elevated ROS levels in both left and right lungs,elevated MDA level,lowered SOD level,and upregulated mRNA and protein levels of NLRP3,ASC,caspase-1,and p-NF-κB p65/NF-κB p65.Compared with the model group,the drug administration in all the groups reduced inflammatory cell infiltration in the lung tissue.The inhibitor group and the western drug group showed enlarged alveolar cavity,thinned interstitium,and reduced inflammation.There was a small amount of alveolar wall rupture in the high-and medium-dose GQYY groups and reduced inflammatory cell infiltration in the low dose GQYY group.Compared with the model group,drug administration lowered level of ROS in the left and right lungs,lowered the MDA level,elevated the SOD level,and down-regulated the mRNA and protein levels of NLRP3,ASC,caspase-1,and p-NF-κB p65/NF-κB p65.GQYY can effectively reduce the damage caused by radiation and bystander effect,which may be associated with the ROS-mediated NLRP3 inflammasome activation.