摘要
目的:探讨苹果多酚(AP)调控Kelch样环氧氯丙烷相关蛋白1(Keap1)/核转录因子E2相关因子2(Nrf2)通路对脂多糖(LPS)诱导大鼠急性肺损伤(ALI)的影响。方法:按照随机数字表法将SD大鼠分为对照(control)组、模型(model)组、低剂量(25 mg/kg)AP组(AP-L组)、高剂量(100 mg/kg)AP组(AP-H组)、地塞米松(DEX)组和AP-H+ML385(Nrf2抑制剂)组,每组12只。各组大鼠根据分组给药,每天腹腔注射给药1次,持续给药14天,control组、model组大鼠腹腔注射等量的生理盐水。末次给药1 h后,除control组外,其它组大鼠均向气管内注射LPS以构建ALI模型,control组大鼠的气管内注射等体积的生理盐水,造模24 h后,收集大鼠肺泡灌洗液、血清及双侧肺组织用于实验。检测肺泡灌洗液中细胞总数、中性粒细胞数;ELISA法检测大鼠血清中肿瘤坏死因子α(TNF-α)、白细胞介素6(IL-6)水平;HE染色观察大鼠肺组织病理损伤情况;检测大鼠肺组织湿重/干重比;试剂盒检测大鼠肺组织中超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)活性及丙二醛(MDA)含量;DCFH-DA荧光探针检测大鼠肺组织中活性氧(ROS)水平;RT-qPCR检测肺组织中Keap1、Nrf2和血红素氧合酶1(HO-1)mRNA的表达;Western blot检测肺组织中Keap1、Nrf2和HO-1蛋白的表达。结果:与control组比较,model组大鼠肺泡灌洗液中细胞总数、中性粒细胞数、TNF-α、IL-6、病理评分、肺湿/干重比、MDA含量、ROS水平升高,SOD、GSH-Px活性、Keap1mRNA、Nrf2 mRNA、HO-1 mRNA、Keap1、HO-1蛋白及核Nrf2蛋白表达降低(P<0.05);与model组比较,AP-L组、APH组、DEX组对应指标变化趋势与上述相反(P<0.05);ML385减弱了高剂量AP对ALI大鼠的保护作用。结论:AP可能通过激活Keap1/Nrf2信号通路对LPS诱导的大鼠ALI发挥保护作用。
AIM:To investigate the effect of apple polyphenols(AP)on lipopolysaccharide(LPS)-induced acute lung injury(ALI)in rats by regulating the Kelch-like epichlorohydrin-associated protein 1(Keap1)/nuclear factor E2-related factor 2(Nrf2)pathway.METHODS:According to the random number table method,SD rats were divided into control group,Model group,low-dose(25 mg/kg)AP(AP-L)group,high-dose(100 mg/kg)AP(AP-H)group,dexamethasone(DEX)group,and AP-H+ML385(Nrf2 inhibitor)group,12 rats in each group.All rats received intraperitoneally injection once a day for 14 days.One hour after injection,except for the control group,the rats in the other groups were injected with LPS into the trachea to build the ALI model.The rats in the control group were injected with an equal volume of normal saline into the trachea,after 24 hours of modeling,the rat bronchoalveolar lavage fluid,serum and bilateral lung tissues were collected for experiments.The total number of cells and the number of neutrophils in the bronchoalveolar lavage fluid were measured;the levels of tumor necrosis factor alpha(TNF-α)and interleukin 6(IL-6)in serum of rats were measured by ELISA;HE staining was applied to detect the pathological damage of rat lung tissue;the ratio of wet weight(W)/dry weight(D)of rat lung tissue was measured;the kit was used to detect the activity of superoxide dismutase(SOD),glutathione peroxidase(GSH-Px)and malondialdehyde(MDA)content in rat lung tissue;2’,7’-dichlorodihydrofluorescein diacetate(DCFH-DA)fluorescent probe was used to detect the level of reactive oxygen species(ROS)in rat lung tissue;RT-qPCR was used to detect Keap1,Nrf2,heme oxygenase 1(HO-1)mRNA expression in lung tissue;Western blot was used to detect the protein expressions of Keap1,Nrf2 and HO-1 in lung tissue.RESULTS:Compared with control group,the total number of cells,neutrophils,TNF-α,IL-6,pathological score,W/D ratio,MDA content and ROS levelsin model group were increased.SOD and GSH-Pxactivity,Keap1 mRNA,Nrf2 mRNA,HO-1 mRNA,Keap1,HO-1and nuclear Nrf2 protein levels were decreased(P<0.05).Compared with the model group,the corresponding indicators of the AP-L group,AP-H group and DEX group showed the opposite trends(P<0.05);ML385 attenuated the protective effect of high-dose AP in ALI rats.CONCLUSION:AP may play a protective effect on LPS-induced ALI rats by activating the Keap1/Nrf2 signaling pathway.
作者
汤建华
詹旭莉
冯平
张志华
TANG Jian-hua;ZHAN Xu-li;FENG Ping;ZHANG Zhi-hua(Department of Pharmacy,The First Affiliated Hospital of Hebei North University,Zhangjiakou 050051,China;Department of Respiratory Medicine,The First Affiliated Hospital of Hebei North University,Zhangjiakou 050051,China)
出处
《中国病理生理杂志》
CAS
CSCD
北大核心
2022年第10期1840-1847,共8页
Chinese Journal of Pathophysiology
基金
2020年政府资助河北省级医学优秀人才项目(No.39003-2)。
作者简介
通讯作者:张志华,Tel:0313-8043503,E-mail:zzh19641229@163.com。
