氧化应激及炎性衰老在老年小鼠支气管哮喘发生中的作用研究

The role of oxidative stress and inflammaging in the development of bronchial asthma in elderly mice

目的观察老年哮喘模型小鼠肺组织、外周血清及支气管肺泡灌洗液上清中氧化应激指标及炎性衰老相关炎症因子表达的变化,探讨氧化应激和炎性衰老在支气管哮喘中的作用。方法雌性SPF级C57BL/6健康小鼠分为老年哮喘模型组(A组)、老年正常对照组(B组)、青年哮喘模型组(C组)和青年正常对照组(D组),每组12只。HE染色观察小鼠肺组织病理学改变;Real Time PCR方法检测小鼠肺组织中超氧化物歧化酶(superoxide dismutase,SOD)、髓过氧化物酶(myeloperoxidase,MPO)、白细胞介素-1β(interleukin-1β,IL-1β)、白细胞介素-6(interleukin-6,IL-6)和肿瘤坏死因子(tumor necrosis factor,TNF-α)基因的表达,ELISA方法检测小鼠BALF上清及外周血清中SOD、MPO、IL-1β、IL-6和TNF-α水平。结果与2个对照组比较,2个哮喘模型组可见相似病理改变,2个哮喘模型组肺组织SOD mRNA的表达量、BALF上清及外周血清中SOD水平减少,而MPO、IL-1β、IL-6和TNF-αmRNA的表达量及BALF上清、外周血清中的含量均增加,差异有统计学意义(P<0.05,P<0.01);老年哮喘模型组肺组织中SOD mRNA的表达量、BALF上清及外周血清中SOD水平均低于青年哮喘模型组,IL-6和TNF-αmRNA的表达量及BALF上清、外周血清中的水平均高于青年哮喘模型组,差异有统计学意义(P<0.05,P<0.01)。结论氧化-抗氧化能力失衡在老年哮喘中更为明显,炎性衰老和氧化应激共同存在于老年哮喘中,在老年哮喘的病理机制中发挥作用。

Objective To observe the changes of oxidative stress indexes and inflammaging-related inflammatory factors in lung tissue,peripheral serum and bronchoalveolar lavage fluid supernatant of elderly asthma model mice,and explore the role of oxidative stress and inflammatory aging in the development of bronchial asthma.Methods Female SPF C57BL/6healthy mice were divided into elderly asthma model group(group A),elderly normal control group(group B),youth asthma model group(group C)and youth normal control group(group D),with12mice in each group.HE staining was used to observe the pathological changes of lung tissue in mice.Real-time PCR was used to detect the gene expression of superoxide dismutase(SOD),myeloperoxidase(MPO),interleukin-1β(IL-1β),interleukin-6(IL-6)and tumor necrosis factor(TNF-α)in lung tissues.ELISA was used to detect the levels of SOD,MPO,IL-1β,IL-6and TNF-αin BALF supernatant and peripheral serum.Results Compared with the two control groups,the two asthma model groups showed similar pathological changes.The expression level of SOD mRNA in lung tissue and SOD level in BALF supernatant and peripheral serum decreased in the two asthma model groups,while the mRNA expression levels of MPO,IL-1β,IL-6and TNF-αand their contents in BALF supernatant and peripheral serum increased,and the difference was statistically significant(P<0.05,P<0.01).The expression of SOD mRNA in lung tissue and the level of SOD in BALF supernatant and peripheral serum in the elderly asthma model group were lower than those in the young asthma model group,while the expression of IL-6and TNF-αmRNA and the leves of IL-6and TNF-αin BALF supernatant and peripheral serum were significantly higher than those in the young asthma model group(P<0.05,P<0.01).Conclusion The imbalance of oxidative-antioxidant capacity is more obvious in aging asthma.Inflammaging and oxidative stress coexist in aging asthma and they play a role in the pathological mechanism of aging asthma.