Page 45 - 2023-03-中国全科医学

·294· http: //www.chinagp.net E-mail: zgqkyx@chinagp.net.cn Jaunary 2023, Vol.26 No.3

【Abstract】 Background Ginkgo biloba extract（GBE）has been found to be effective in inhibiting the airway and
systemic inflammatory response and improve airway remodeling in rat models of chronic obstructive pulmonary disease（COPD），
but the mechanism remains unclear. Objective To discuss the mechanism of GBE regulating alveolar macrophage autophagy
through phosphatidylinositol 3-kinase（PI3K）/protein kinase B（Akt）/mammalian target of rapamycin（mTOR）signaling
pathways to prevent and treat COPD. Methods A total of 90 SPF male Wistar rats were equally randomized into normal control
group，COPD model group，GBE group，bicalutamide group，rapamycin group，and Taselisib group. The normal control group
were normally fed except that normal saline was injected into their trachea on the 1st and 14th days of intervention，the other
5 groups were treated with exposure to cigarette smoking combined with intratracheal injection of lipopolysaccharide（LPS）
to establish rat models of COPD. The GBE group received intraperitoneal injection of Shuxuening injection from the 15th day to
the 28th day of the experiment，while bicalutamide，rapamycin，and Taselisib groups were given bicalutamide，rapamycin，
and taselisib，respectively，from the 29th day to the 42nd day of the experiment. HE staining was used to observe alveolar
pathological changes and airway remodeling. ELISA was used to detect the levels of interleukin -6（IL-6）and interleukin -8
（IL-8）in alveolar lavage fluid （BALF） and the serum. The number of alveolar macrophages was counted under microscope.
The ultrastructure of alveolar macrophages was observed by transmission electron microscope. Western blotting was used to
measure the expression levels of autophagy-related proteins in alveolar macrophages. The ratio of microtubule-associated protein
light chain 3（LC3）- Ⅱ /LC3- Ⅰ was calculated subsequently. Results As of the models being successfully established，
the rats in normal control，COPD model，GBE，bicalutamide，rapamycin，and Taselisib groups numbered 12，11，12，
12，12，and 11，respectively. H&E staining showed that the degree of alveolar injury in COPD model group was more severe
than that of GBE，bicalutamide，rapamycin，or Taselisib group（P<0.05）. COPD model group had larger mean linear
intercept and mean alveolar area as well as less mean alveolar number than GBE，bicalutamide，rapamycin，or Taselisib group
（P<0.05）. Moreover，COPD model group had less complete bronchial wall structure than GBE，bicalutamide，rapamycin，
or Taselisib group. The levels of BALF and serum IL-6 and IL-8 in COPD model group were higher than those of each of other
five groups（P<0.05）. Among all groups，the number of macrophages in the normal control group was the lowest，while that
of COPD model group was the highest（P<0.05）.Transmission electron microscopy showed that COPD model group had less
autophagolysosomes in alveolar macrophages than GBE，bicalutamide，rapamycin，or Taselisib group. The normal control group
had higher expression levels of PI3Kp110α，Akt，p-Ak，mTOR and p-mTOR and lower ratio of LC3-II/LC3-I than each of
other five groups （P<0.05）. COPD model group had higher expression levels of PI3Kp110α，Akt，p-Akt，mTOR and p-mTOR，
and lower ratio of LC3- Ⅱ /LC3- Ⅰ compared with GBE，bicalutamide，rapamycin or Taselisib group（P<0.05）. Conclusion
GBE maintained the autophagy function of alveolar macrophages，reduced macrophage infiltration，inhibited the inflammatory
response and alveolar damage，and improved airway remodeling in model rats of COPD through regulating the PI3K/Akt/mTOR
signaling pathway.
【Key words】 Pulmonary disease，chronic obstructive；Ginkgo biloba extract；PI3K/Akt/mTOR signal pathway；
Alveolar macrophages；Autophagy

慢 性 阻 塞 性 肺 疾 病（chronic obstructive pulmonary 吸烟是 COPD 的首要发病因素，研究发现吸烟者的肺泡
disease，COPD）是一种常见的慢性呼吸系统疾病， 巨噬细胞存在自噬功能缺陷，吸烟者的肺泡巨噬细胞内
疾病负担严重，根据世界卫生组织（WHO）预测，到 出现自噬体的异常蓄积，从而导致自噬体成熟障碍，引
2030 年 COPD 将成为人类第三大死亡原因 ［1］ 。COPD 起蛋白质聚集清除受损，线粒体功能失调，以及细菌向
［7］
发病机制主要包括慢性气道炎症、氧化 - 抗氧化失衡、 溶酶体的传递缺陷 。如何抑制巨噬细胞释放促炎因子，
蛋白酶 - 抗蛋白酶失衡及免疫相关机制 ［2］ ，其中巨噬 改善 COPD 患者肺泡巨噬细胞自噬缺陷已逐渐成为防治
细胞参与免疫相关的调节，通过释放促炎递质，包括趋 COPD 的新热点。
化因子、细胞因子、蛋白酶等，在协调 COPD 的炎症过 磷脂酰肌醇 3- 激酶（PI3K）/ 蛋白激酶 B（Akt）/
程中发挥重要作用 ［3］ 。肺巨噬细胞数量增加与功能受 哺乳动物雷帕霉素靶蛋白（mTOR）通路是细胞内重要
损是 COPD 发病的重要机制 ［4］ 。自噬是细胞通过自噬 的信号传导途径之一，参与调控细胞生长、增殖、分化、
溶酶体溶解细胞内受损蛋白质、细胞器等来维持细胞稳 自噬和凋亡等 ［8］ ，在细胞自噬中发挥关键作用 ［9］ 。银
态的一种重要的分解代谢过程 ［5］ ，为细胞修复、再生 杏叶提取物（ginkgo biloba extract，GBE）是从银杏的干
及延续提供条件。自噬在维持肺部炎性反应系统的正常 燥叶中提取而来的以黄酮类、萜类内酯为主要活性成分
功能和 COPD 的病情进展中起着至关重要的作用 ［6］ 。 的混合物，具有改善血液循环、抗血小板聚集、清除自