Pulmonary fibrosis (PF) is a chronic and irreversible scarring disease in the lung with limited treatment options. Therefore, it is critical to identify new therapeutic options. This study was undertaken to identify the effects of tannic acid (TA), a naturally occurring dietary polyphenol, in a mouse model of PF. Bleomycin (BLM) was intratracheally administered to induce PF. Administration of TA significantly reduced BLM-induced histological alterations, inflammatory cell infiltration and the levels of various inflammatory mediators (nitric oxide, leukotriene B4 and cytokines). Additionally, treatment with TA also impaired BLM-mediated increases in pro-fibrotic (transforming growth factor-β1) and fibrotic markers (alpha-smooth muscle actin, vimentin, collagen 1 alpha and fibronectin) expression. Further investigation indicated that BLM-induced phosphorylation of Erk1/2 (extracellular signal-regulated kinases 1 and 2) in lungs was suppressed by TA treatment. Findings of this study suggest that TA has the potential to mitigate PF through inhibiting the inflammatory response and fibrotic process in lungs and that TA might be useful for the treatment of PF in clinical practice.

中文翻译：

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单宁酸通过抑制炎症反应和纤维化过程来减轻小鼠的实验性肺纤维化。

肺纤维化（PF）是一种慢性且不可逆的肺部瘢痕病，治疗选择有限。因此，确定新的治疗选择至关重要。进行这项研究以鉴定单宁酸（TA）（一种天然存在的膳食多酚）在PF小鼠模型中的作用。气管内施用博来霉素（BLM）诱导PF。给予TA可显着降低BLM诱导的组织学改变，炎性细胞浸润和各种炎性介质（一氧化氮，白三烯B4和细胞因子）的水平。此外，TA的治疗还损害了BLM介导的促纤维化（转化生长因子-β1）和纤维化标记物（α平滑肌肌动蛋白，波形蛋白，胶原1α和纤连蛋白）表达的增加。进一步的研究表明，BLM诱导的肺部Erk1 / 2磷酸化（细胞外信号调节激酶1和2）被TA处理抑制。这项研究的发现表明，TA具有通过抑制肺部的炎症反应和纤维化过程来减轻PF的潜力，并且TA可能在临床实践中可用于治疗PF。