BACKGROUND Bletilla striata is a traditional Chinese medicine used to treat hemorrhage, scald, gastric ulcer, pulmonary diseases and inflammations. In this study, we investigated bioactivity of the effective fraction of B. striata (EFB) in reducing the inflammatory cytokine production induced by water or organic extracts of PM2.5. METHODS PM2.5 extracts were collected and analyzed by chromatographic system and inductively coupled plasma mass spectrometer. Cell viability was measured using MTS (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) assay, and cell supernatant was analyzed by flow cytometry, ELISA, and qRT-PCR in cultured mouse macrophage cell line RAW264.7 treated with EFB and PM2.5 extracts. Expressions of nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathway were measured by Western blot. RESULTS PM2.5 composition is complex and the toxicity of PM2.5 extracts were not noticeable. The treatment of EFB at a wide dose-range of 0-40 μg/mL did not cause significant change of RAW264.7 cell proliferation. EFB pretreatment decreased the inflammatory cytokines in the macrophage. Further analysis showed that EFB significantly attenuated PM2.5-induced proinflammatory protein expression and downregulated the levels of phosphorylated NF-κBp65, inhibitor of kappa B (IκB)-α, c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK), and p38. CONCLUSIONS Our study demonstrated the potential effectiveness of B. striata extracts for treating PM2.5-triggered pulmonary inflammation.

中文翻译：

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白芨的有效部分在体外可减少水和空气中细颗粒物 (PM2.5) 有机提取物诱导的炎症细胞因子的产生。


背景技术白及是一种中药，用于治疗出血、烫伤、胃溃疡、肺部疾病和炎症。在这项研究中，我们研究了 B. striata 有效部位 (EFB) 在减少 PM2.5 水或有机提取物诱导的炎症细胞因子产生方面的生物活性。方法收集PM2.5提取物，采用色谱系统和电感耦合等离子体质谱仪进行分析。使用MTS（3-（4,5-二甲基噻唑-2-基）-5-（3-羧甲氧基苯基）-2-（4-磺基苯基）-2H-四唑）测定法测量细胞活力，并通过流式分析细胞上清液在用 EFB 和 PM2.5 提取物处理的培养的小鼠巨噬细胞系 RAW264.7 中进行细胞计数、ELISA 和 qRT-PCR。通过Western blot检测核因子κB（NF-κB）和丝裂原激活蛋白激酶（MAPK）信号通路的表达。结果 PM2.5成分复杂，PM2.5提取物毒性不明显。 0-40 μg/mL 宽剂量范围的 EFB 处理并未引起 RAW264.7 细胞增殖的显着变化。 EFB预处理减少了巨噬细胞中的炎症细胞因子。进一步分析表明，EFB 显着减弱 PM2.5 诱导的促炎蛋白表达，并下调磷酸化 NF-κBp65、κ B 抑制剂 (IκB)-α、c-Jun N 末端激酶 (JNK)、细胞外信号调节的水平激酶 (ERK) 和 p38。结论 我们的研究证明了 B. striata 提取物对于治疗 PM2.5 引发的肺部炎症的潜在功效。