Abstract:

Objective　To study lycorine in interfering with bleomycin-induced pulmonary fibrosis in mice by inhibiting endoplasmic reticulum stress. Methods　From January to February 2022, 50 male mice, weighing 22-26 g, were divided into a normal group, a model group, a low-dose lycorine group, a medium-dose lycorine group, and a high-dose lycorine group by the random number table method, with 10 in each group. The mouse models of pulmonary fibrosis were replicated by oropharyngeal tracheal instillation of bleomycin normal saline solution, and all the mice were administered for 28 days. Hematoxylin and eosin staining (HE staining) and Masson's trichrome staining were used to detect the pathological changes of mouse lung tissue. Western Blotting was used to detect the protein expression levels of Bip, PERK, α-SMA, and p-eIF2α in lung tissue. Results　The lung tissue of the mice in the model group had structural disorder, thickening of alveolar wall, severe inflammatory cell infiltration in alveoli, and a lot of collagen deposition in alveolar interstitium. And the pathological improvement of lung tissue in the medium-dose lycorine group and the high-dose lycorine group was the most obvious. The collagen area of Masson in the model group was significantly lower than that in the normal group [(34.42±5.13) mm² vs. (5.15±1.16) mm²]; the collagen area in the high-dose lycorine group was significantly lower than that in the medium-dose lycorine group [(15.70±4.09) mm² vs. (19.83±3.14) mm²]; there were statistical differences (both P<0.05). The protein expression levels of Bip, PERK, α-SMA, and p-eIF2α in the lung tissue of the model group were significantly higher than those of the normal group. The protein expression levels of Bip, PERK, α-SMA, and p-eIF2α in the lung tissue of the medium-dose lycorine group and the high-dose lycorine group were significantly lower than those of the model group. The protein expression levels of Bip, PERK, α-SMA, and p-eIF2α in the lung tissue of the high-dose lycorine group were significantly lower than those of the medium-dose lycorine group. Conclusion　Lycorine can interfere with bleomycin-induced pulmonary fibrosis in mice, and its mechanism of action may be the inhibition of endoplasmic reticulum stress.

Key words:

Pulmonary fibrosis, Endoplasmic reticulum stress, Lycorine, Unfolded protein effect, Animal experiment, Bleomycin-induced

摘要：

目的　研究石蒜碱通过抑制内质网应激干预博来霉素诱导肺纤维化小鼠。方法　实验时间为2022年1月至2月，选取50只小鼠，雄性，体质量22～26 g，按随机数字表法分为五组：正常组、模型组、石蒜碱低剂量组、石蒜碱中剂量组、石蒜碱高剂量组，每组10只。通过口咽气管滴注法滴注博来霉素生理盐水溶液复制肺纤维化小鼠模型，连续灌胃给药28 d。苏木精-伊红染色（HE染色）、Masson三色染色检测小鼠肺组织病理变化，Western Blotting 检测肺组织中免疫球蛋白重链结合蛋白（Bip）、内质网调节激酶（PERK）、α-平滑肌肌动蛋白（α-SMA）、磷酸化真核细胞起始因子2α（p-eIF2α）蛋白表达水平。统计学方法采用单因素方差分析。结果　模型组小鼠分组结构紊乱，肺泡壁增厚，肺泡内有严重的炎性细胞浸润，肺泡间质有很多胶原沉积；石蒜碱各剂量组肺组织的上述病理改善较模型组有改善，且石蒜碱中剂量组和石蒜碱高剂量组肺组织的病理改善最为明显；模型组Masson的胶原面积高于正常组［（34.42±5.13）mm²比（5.15±1.16）mm²］，石蒜碱高剂量组胶原面积低于石蒜碱中剂量组［（15.70±4.09）mm²比（19.83±3.14）mm²］，差异均有统计学意义（均P<0.05）；模型组肺组织中Bip、PERK、α-SMA、p-eIF2α蛋白表达水平均高于正常组，石蒜碱中剂量组和石蒜碱高剂量组肺组织中Bip、PERK、α-SMA、p-eIF2α蛋白表达水平均低于模型组，石蒜碱高剂量组肺组织中Bip、PERK、α-SMA、p-eIF2α蛋白表达水平均低于石蒜碱中剂量组。结论　石蒜碱可以干预博来霉素诱导肺纤维化小鼠，且其作用机制可能为抑制内质网应激。

关键词:

肺纤维化, 内质网应激, 石蒜碱, 未折叠蛋白反应, 动物实验, 博来霉素