Lipopolysaccharide induced the proliferation of mouse lung fibroblasts by suppressing FoxO3a/p27 pathway
Lipopolysaccharide induced the proliferation of mouse lung fibroblasts by suppressing FoxO3a/p27 pathway
复制标题
脂多糖通过抑制FoxO3a/p27通路诱导小鼠肺成纤维细胞增殖
DOI：
10.1002/cbin.11016
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发表时间：
2018-10-01
影响因子：
3.9
通讯作者：
Wen, Daxiang
中科院分区：
文献类型：
--
作者：
Gu, Nannan;Xing, Shunpeng;Wen, Daxiang
肺成纤维细胞的异常聚集和活化是肺纤维化的关键过程，但其机制仍不清楚。Forkhead Box O3 a（FoxO 3a）被认为是一种重要的转录因子，可以调节细胞周期和细胞活力。为了研究FoxO 3a在LPS诱导的肺成纤维细胞增殖中的作用，我们将FoxO 3a-SiRNA或FoxO 3a-OE慢病毒转染到培养的小鼠肺成纤维细胞中以敲低或过表达FoxO 3a，并用吉非替尼预处理小鼠肺成纤维细胞以增强FoxO 3a活性。CCK-8法检测细胞增殖，Western blot法检测FoxO 3a、磷酸化FoxO 3a（p-FoxO 3a）和p27蛋白的表达。我们发现LPS介导的小鼠肺成纤维细胞增殖伴随着FoxO 3a的失活。FoxO 3a基因的敲低可进一步降低LPS诱导的肺成纤维细胞p27的表达，而FoxO 3a基因的过表达可显著增加LPS诱导的肺成纤维细胞p27的表达，抑制LPS诱导的肺成纤维细胞增殖。吉非替尼可降低FoxO 3a的磷酸化水平，使FoxO 3a转位到细胞核内，增加p27的表达，有效抑制LPS介导的肺成纤维细胞增殖。结果表明，FoxO 3a的过表达和磷酸酶活性降低通过激活FoxO 3a/p27信号通路抑制LPS诱导的肺成纤维细胞增殖。因此，增强FoxO 3a活性可能是LPS诱导的肺纤维化的潜在治疗靶点。
Aberrant aggregation and activation of lung fibroblasts is a key process in pulmonary fibrosis, but the underlying mechanism remains enigmatic. Forkhead Box O3a (FoxO3a) is considered to be an important transcription factor that could regulate both cell cycle and cell viability. To investigate the role of FoxO3a on LPS-induced lung fibroblast proliferation, we transfected FoxO3a-SiRNA or FoxO3a-OE lentivirus into cultured mouse lung fibroblasts to knockdown or overexpress FoxO3a and pretreated mouse lung fibroblasts with gefitinib to enhance FoxO3a activity. The proliferation of lung fibroblasts was evaluated by CCK8 assay, the expression of FoxO3a, phosphorylated FoxO3a (p-FoxO3a) and p27 were measured by Western blot. We found that the proliferation of mouse lung fibroblasts mediated by LPS is accompanied by the inactivation of FoxO3a. The knockdown of FoxO3a could further decreased the expression of p27 mediated by LPS, while the overexpression of FoxO3a significantly increased the expression of p27 and suppressed LPS-induced lung fibroblast proliferation. Upon treating fibroblasts with gefitinib, the phosphorylation of FoxO3a was reduced and FoxO3a translocated into the nucleus, the expression of p27 was significantly increased and the proliferation of lung fibroblasts mediated by LPS could also be inhibited effectively. The results indicate that overexpression and reduced phosphatase activity of FoxO3a inhibit LPS-induced lung fibroblast proliferation through the activation of FoxO3a/p27 signaling pathways. Thus, to enhance FoxO3a activity could be a potential therapeutic target for LPS-induced pulmonary fibrosis.