Liu Lijing, Qian Hong, Xiao Hua, He Jianbin, Xie Maofeng, Wang Zaiyan, Long Xingyun
School of Clinical Medicine, Hunan University of Medicine, Huaihua 418000, China.
Department of Respiration, First Affiliated Hospital, University of South China, Hengyang 421001, China.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi. 2016 Oct;32(10):1342-1346.
Objective To explore the role of transforming growth factor-β1 (TGF-β1)/a disintegrin-like and metalloproteinase with thrombospondin type 1 motif (ADAMTS-1) signaling pathway in emodin's anti-pulmonary fibrosis. Methods Sixty SD rats were randomly divided into 6 groups: normal control group, sham-operated group, model group, low-dose emodin intervention group (20 mg/kg), high-dose emodin intervention group (80 mg/kg) and prednisone group (5 mg/kg). Each group included 10 animals. Rats in the latter 4 groups were intratracheally injected with bleomycin A5 to induce pulmonary fibrosis, whereas bleomycin A5 was replaced by normal saline in sham-operated group. From the second day, rats in the low- and high-dose emodin intervention groups were intragastrically treated with 2 mL of 20 and 80 mg/kg emodin, respectively. Rats in the prednisone group were intragastrically administrated with 2 mL of 5 mg/kg prednisone acetate. However, rats in the normal control and sham-operated and model groups were treated with 2 mL of normal saline. All rats were sacrificed on day 28 after modeling. Subsequently, blood and pulmonary tissue specimen were taken. The pathological changes of pulmonary tissues were observed using routine HE and Masson staining. The expressions of TGF-β1, ADAMTS-1, collagen type 1 (Col1) and Col3 in pulmonary tissues were measured by quantitative real-time PCR and Western blotting. Serum levels of procollagen type 1 carboxy terminal propeptide (P1CP) and procollagen type 3 aminoterminal propeptide (P3NP) were detected by ELISA. Results Compare with the model group, the alveolitis and pulmonary fibrosis extent in each drug-treated group were significantly alleviated. In comparison with normal control group or sham-operated group, the mRNA and protein levels of TGF-β1, Col1 and Col3 in pulmonary tissues and the serum levels of P1CP and P3NP increased, but the mRNA and protein levels of ADAMTS-1 decreased in model group. After treatment with low- and high-dose emodin or prednisone, the mRNA and protein levels of TGF-β1, Col1 and Col3 in pulmonary tissues and the serum levels of P1CP and P3NP were significantly downregulated, while the mRNA and protein levels of ADAMTS-1 in pulmonary tissues were significantly upregulated as compared with the model group. Moreover, In comparison with the low-dose emodin intervention group, the above indicators were significantly improved in the high-dose emodin intervention or prednisone group. However, the above indicators were not significantly different between the high-dose emodin intervention group and the prednisone group. Conclusion Increased degradation of Col1 and Col3 in pulmonary tissues due to the inactivation of TGF-β1/ADAMTS-1 signaling pathway may be a significant mechanism by which emodin protects rats against pulmonary fibrosis.
目的 探讨转化生长因子-β1（TGF-β1）/含血小板反应蛋白基序的解聚素样金属蛋白酶-1（ADAMTS-1）信号通路在大黄素抗肺纤维化中的作用。方法 将60只SD大鼠随机分为6组：正常对照组、假手术组、模型组、低剂量大黄素干预组（20 mg/kg）、高剂量大黄素干预组（80 mg/kg）和泼尼松组（5 mg/kg）。每组10只动物。后4组大鼠经气管内注射博来霉素A5诱导肺纤维化，假手术组用生理盐水代替博来霉素A5。从第2天起，低、高剂量大黄素干预组大鼠分别用2 mL含20和80 mg/kg大黄素的溶液灌胃。泼尼松组大鼠用2 mL含5 mg/kg醋酸泼尼松的溶液灌胃。而正常对照组、假手术组和模型组大鼠用2 mL生理盐水处理。建模后第28天处死所有大鼠。随后，采集血液和肺组织标本。采用常规HE和Masson染色观察肺组织的病理变化。通过定量实时PCR和蛋白质印迹法检测肺组织中TGF-β1、ADAMTS-1、Ⅰ型胶原（Col1）和Ⅲ型胶原（Col3）的表达。采用酶联免疫吸附测定法检测血清中Ⅰ型前胶原羧基端前肽（P1CP）和Ⅲ型前胶原氨基端前肽（P3NP）水平。结果 与模型组相比，各药物治疗组的肺泡炎和肺纤维化程度均明显减轻。与正常对照组或假手术组相比，模型组肺组织中TGF-β1、Col1和Col3的mRNA和蛋白水平以及血清中P1CP和P3NP水平升高，但ADAMTS-1的mRNA和蛋白水平降低。低、高剂量大黄素或泼尼松治疗后，与模型组相比，肺组织中TGF-β1、Col1和Col3的mRNA和蛋白水平以及血清中P1CP和P3NP水平均明显下调，而肺组织中ADAMTS-1的mRNA和蛋白水平明显上调。此外，与低剂量大黄素干预组相比，高剂量大黄素干预组或泼尼松组上述指标均明显改善。然而，高剂量大黄素干预组与泼尼松组上述指标差异无统计学意义。结论 TGF-β1/ADAMTS-1信号通路失活导致肺组织中Col1和Col3降解增加可能是大黄素保护大鼠抗肺纤维化的重要机制。
