苦杏仁苷对支气管哮喘大鼠Kelch样环氧氯丙烷相关蛋白-1/核因子E2相关因子2信号通路的影响

Effect of amygdalin on Kelch-like epichlorohydrin-related protein-1/nuclear factor E2-related factor 2 signaling pathway in bronchial asthma rats

目的探讨苦杏仁苷对支气管哮喘大鼠Kelch样环氧氯丙烷相关蛋白-1(Kelch-like epichlorohydrin-related protein-1,Keap1)/核因子E2相关因子2(nuclear factor E2-related factor 2,Nrf2)信号通路的影响。方法用卵蛋白腹腔注射及雾化吸入建立支气管哮喘模型;另取12只正常大鼠作为空白组,给予等量0.9%NaCl腹腔注射及雾化吸入。将造模成功大鼠随机分为模型组、对照组及低、中、高剂量实验组,各12只。模型组和空白组分别灌胃给予0.9%NaCl 10 mL·kg^(-1)·d^(-1);对照组灌胃给予0.08 mg·mL^(-1)地塞米松溶液10 mL·kg^(-1)·d^(-1);低、中、高剂量实验组分别灌胃给予6,8和12 mg·mL^(-1)的苦杏仁苷溶液10 mL·kg^(-1)·d^(-1)。各组大鼠均给药2周。用苏木素-伊红染色法观察支气管管壁厚度及平滑肌厚度,用蛋白质印迹法观察肺组织Keap-1和Nrf2的表达水平。结果低、高剂量实验组和对照组、模型组、空白组的支气管管壁厚度分别为(5.71±0.63)%,(3.82±0.37)%,(3.78±0.34)%,(7.89±0.84)%和(2.48±0.31)%,平滑肌厚度分别为(3.16±0.44)%,(2.11±0.22)%,(2.09±0.18)%,(4.28±0.53)%和(1.09±0.14)%,Keap-1蛋白相对表达水平分别为0.37±0.05,0.20±0.02,0.19±0.03,0.59±0.07和0.07±0.01,Nrf2蛋白相对表达水平分别为0.22±0.03,0.38±0.05,0.37±0.04,0.17±0.02和0.63±0.08,模型组的上述指标与空白组比较,低、高剂量实验组和对照组的上述指标与模型组比较,差异均有统计学意义(均P<0.05)。结论苦杏仁苷能有效抑制气道重塑,防止病情进展,且药物剂量越大效果越明显,其作用可能与激活Keap-1/Nrf2抗氧化信号通路有关。

Objective To analyze the effects of amygdalin on Kelch-like epichlorohydrin-related protein-1(Keap1)/nuclear factor E2-related factor 2(Nrf2)signaling pathway in bronchial asthma rats.Methods The bronchial asthma model was established by intraperitoneal injection and aerosol inhalation of ovalbumin;and another 12 normal rats in the blank group were given same amount of 0.9%NaCl by intraperitoneal injection and aerosol inhalation.Model rats were randomly divided into model group,control group and experimental-L,-M,-H groups,each with 12 rats.The model group and blank group were given 0.9%NaCl 10 mL·kg^(-1)·d^(-1)respectively by gavage;control group were given 0.08 mg·m L^(-1)dexamethasone solution 10 mL·kg^(-1)·d^(-1)by gavage;experimental-L,-M,-H groups were given 6,8,12 mg·mL^(-1)amygdalin solution 10 mL·kg^(-1)·d^(-1)respectively by gavage.All rats in each group were treated for 2 weeks.The bronchial tube wall thickness and smooth muscle were observed by hematoxylin eosin staining,the expression levels of Keap-1 and Nrf2 in lung tissue were observed by Western blot.Results The bronchial wall thickness in rats of experimental-L,-H groups,control group,model group and blank group were(5.71±0.63)%,(3.82±0.37)%,(3.78±0.34)%,(7.89±0.84)%and(2.48±0.31)%;smooth muscle thickness were(3.16±0.44)%,(2.11±0.22)%,(2.09±0.18)%,(4.28±0.53)%and(1.09±0.14)%;the relative expression levels of Keap-1 protein were 0.37±0.05,0.20±0.02,0.19±0.03,0.59±0.07 and 0.07±0.01;the relative expressions levels of Nrf2 protein were 0.22±0.03,0.38±0.05,0.37±0.04,0.17±0.02 and 0.63±0.08.The above indexes of the model group were compared with those of normal group,and the above indexes of the experimental-L,-H groups and control group were compared with those of model group,the differences were statistically significant(all P<0.05).Conclusion Amygdalin can effectively inhibit airway remodeling and prevent disease progression,and the higher the dosage,the more obvious the effect,which may be related to the activation of Keap-1/Nrf2 antioxidant signal pathway.