NOD样受体热蛋白结构域相关蛋白3对哮喘小鼠气道炎症反应及细胞焦亡的调控作用

Regulatory effect of NLRP3 on airway inflammatory response and pyroptosis in mice with asthma

摘要:

目的 研究NOD样受体热蛋白结构域相关蛋白3（nod-like receptor，pyrin domain containing 3，NLRP3）对哮喘小鼠气道炎症反应及细胞焦亡的调控作用。 方法 将NLRP3野生型（wild type，WT）C57BL/6J小鼠分为NLRP3-WT对照组、NLRP3-WT哮喘组，NLRP3敲除（knockout，KO）小鼠分为NLRP3-KO对照组、NLRP3-KO哮喘组，每组各10只。采用卵白蛋白+氢氧化铝腹腔注射致敏、卵白蛋白吸入激发的方法建立哮喘模型。检测各组小鼠气道反应性指标增强呼气间歇；苏木精-伊红染色观察各组小鼠肺组织形态学改变，并进行炎症评分；收集各组小鼠支气管肺泡灌洗液，计数中性粒细胞、嗜酸性粒细胞、淋巴细胞数目，并检测白细胞介素（interleukin，IL）-1β、IL-18含量；采用Western blot法检测各组小鼠肺组织中NLRP3、裂解型含半胱氨酸的天冬氨酸蛋白水解酶-1、Gasdermin D-N表达水平的差异。 结果 与NLRP3-WT对照组相比，NLRP3-WT哮喘组小鼠肺组织出现气道平滑肌增厚、炎性细胞浸润等形态学改变；NLRP3-KO哮喘组小鼠上述形态学表现较NLRP3-WT哮喘组小鼠明显改善。与NLRP3-WT对照组相比，NLRP3-WT哮喘组小鼠增强呼气间歇、肺组织炎症评分，支气管肺泡灌洗液中性粒细胞、嗜酸性粒细胞、淋巴细胞计数及IL-1β、IL-18含量，肺组织中NLRP3、裂解型含半胱氨酸的天冬氨酸蛋白水解酶-1、Gasdermin D-N的表达水平均升高（P<0.05）；NLRP3-KO哮喘组小鼠上述各检测指标水平均低于NLRP3-WT哮喘组（P<0.05）。 结论 NLRP3高表达与哮喘发病有关，激活气道炎症反应及细胞焦亡可能是与之相关的分子机制。 引用格式:

Abstract:

Objective To study the regulatory effect of the NOD-like receptor, pyrin domain-containing 3 (NLRP3) on airway inflammatory response and pyroptosis in mice with asthma. Methods The NLRP3 wild-type (WT) C57BL/6J mice were divided into two groups: NLRP3-WT control and NLRP3-WT asthma. The mice with NLRP3 knockout (KO) were divided into two groups: NLRP3-KO control and NLRP3-KO asthma (n=10 each). A model of asthma was prepared by intraperitoneal injection of ovalbumin + aluminium hydroxide for sensitization and ovalbumin inhalation for challenge. Enhanced pause, an index for airway responsiveness, was measured for each group. Hematoxylin and eosin staining was used to observe the histomorphological changes of lungs and determine the inflammation score for each group. Bronchoalveolar lavage fluid was collected from each group to determine the numbers of neutrophils, eosinophils, and lymphocytes and measure the content of interleukin-1β (IL-1β) and interleukin-18 (IL-18). Western blot was used to measure the expression of NLRP3, cleaved caspase-1, and Gasdermin D-N in lung tissue of each group. Results Compared with the NLRP3-WT control group, the NLRP3-WT asthma group showed morphological changes including airway smooth muscle thickening and inflammatory cell infiltration. Compared with the NLRP3-WT asthma group, the NLRP3-KO asthma group had significant improvements in the above morphological manifestations. Compared with the NLRP3-WT control group, the NLRP3-WT asthma group had significant increases in the enhanced pause, the inflammation score of lung tissue, the numbers of neutrophils, eosinophils and lymphocytes in bronchoalveolar lavage fluid, and the levels of IL-1β and IL-18 in bronchoalveolar lavage fluid (P<0.05). The expression of NLRP3, cleaved caspase-1, and Gasdermin D-N in lung tissue also significantly increased in the NLRP3-WT asthma group (P<0.05). The above indices in the NLRP3-KO asthma group were significantly lower than those in the NLRP3-WT asthma group (P<0.05). Conclusions The overexpression of NLRP3 is associated with the pathogenesis of asthma, which may be related to the molecular mechanisms of the activation of airway inflammatory response and pyroptosis. Citation: