麦门冬汤加减方对特发性肺纤维化小鼠PI3K/AKT/mTOR通路的调控

Regulation of Maimendong Decoction on PI3K/Akt/mTOR Pathway in Mice with Idiopathic Pulmonary Fibrosis

目的:探讨麦门冬汤加减方对特发性肺纤维化小鼠转化生长因子-β1(Transforming growth factor-β1,TGF-β1)、平滑肌肌动蛋白(α-smooth muscle actin, α-SMA)、胶原I(Collagen type I, COL1A)表达的影响以及对PI3K/AKT/mTOR通路的调控作用。方法:将120只SPF级ICR小鼠随机分入空白组、模型组、吡菲尼酮组和麦门冬汤加减方组,用博来霉素(5 mg/kg)建立特发性肺纤维化模型,24 h后分别给予相应的药物治疗。吡菲尼酮组和麦门冬汤加减方组小鼠分别灌胃吡菲尼酮和中药麦门冬汤加减方,空白组和模型组小鼠灌胃生理盐水,各组均连续给药3周(21d)后取材。观察指标:各组小鼠的肺系数;肺组织病理变化;肺组织TGF-β1、α-SMA、COL1A的表达量(免疫组化);肺组织中α-SMA、COL1A、p-PI3K、p-AKT、m TOR的蛋白表达量(Western blot);肺组织中TGF-β1、α-SMA、COL1A的m RNA表达量(qPCR)。结果:模型组小鼠的肺系数显著增加,麦门冬汤加减方组肺系数显著降低;模型组小鼠肺组织中有较多炎性细胞浸润,胶原沉积明显,肺泡结构破坏严重,麦门冬汤加减方组小鼠肺组织病理改变较模型组明显减轻,胶原沉积大量减少,肺泡结构逐渐修复;麦门冬汤加减方组较模型组α-SMA、COL1A、TGF-β1的蛋白表达量显著降低(P<0.01);麦门冬汤加减方组较模型组α-SMA、COL1A、p-PI3K、p-AKT、m TOR的蛋白表达量显著下调(P<0.01);麦门冬汤加减方组较模型组α-SMA、COL1A、TGF-β1的m RNA表达量显著降低(P<0.01)。结论:麦门冬汤加减方能有效改善博来霉素诱导的特发性肺纤维化,降低α-SMA、COL1A、TGF-β1的表达,可能是通过调控PI3K/AKT/mTOR信号通路,抑制上皮间充质转化,减少细胞外基质沉积而发挥作用。

Objective: To investigate the effect of Maimendong Decoction on transforming growth factor in mice with idiopathic pulmonary fibrosis-β1(Transforming growth factor-β1, TGF-β1), α-smooth muscle actin(α-SMA), Collagen type I(COL1A) expression and regulation of PI3K/AKT/mTOR pathway. Methods: 120 SPF ICR mice were randomly divided into blank group, model group,pirfenidone group and traditional Chinese medicine group. The IPF model was replicated with bleomycin(5 mg/kg) and treated with corresponding drugs 24 hours later. The mice in the piffinone group and the Maimendong decoction plus and minus prescription group were intragastrically infused with pirfenidone and the traditional Chinese medicine Maimendong decoction, respectively, and the mice in the blank group and model group were intragastrically injected with normal saline, and the samples were taken after continuous administration for 3 weeks(21 days). Observation index: Lung coefficient and pathological changes of lung tissue in each group;Lung tissue TGF-β1, α-SMA and COL1A;TGF-β 1, α-SMA and COL1A(qPCR), and α-SMA, COL1A, p-PI3K, p-AkT and m TOR(Western blot). Results: The lung coefficient of mice in the model group increased significantly, while that in the Maimendong decoction group decreased significantly, there were more inflammatory cell infiltration, obvious collagen deposition and serious destruction of alveolar structure in the model group. The pathological changes of lung tissue in the Maimendong decoction group were significantly less than those in the model group, the collagen deposition decreased greatly, and the alveolar structure was repaired gradually. The protein expressions of α-SMA, COL1A, TGF-β1, α-SMA, COL1A, p-PI3K, p-AKT, m TOR and m RNA expression of α-SMA, COL1A and TGF-β1 in Maimendong decoction group were significantly lower than those in model group(P<0.01), and the protein expressions ofα-SMA, COL1A, TGF-β1 in Maimendong decoction modified prescription group were significantly lower than those in model group(P<0.01), and the protein expressions of α-SMA, COL1A, TGF-β1 in Maimendong decoction modified prescription group were significantly lower than those in model group(P<0.01). Conclusion: Maimendong decoction can effectively improve bleomycin induced pulmonary fibrosis and reduce α-SMA, COL1A, TGF-β1 may play a role by regulating PI3K/AKT/mTOR signaling pathway, inhibiting epithelial mesenchymal transformation and reducing extracellular matrix deposition.