Epidemiological studies have shown that particulate matter with an aerodynamic diameter less than 2.5 μm (PM_2.5) is closely associated with human health issues, especially pulmonary diseases such as chronic obstructive pulmonary disease (COPD), asthma and lung cancer. In this study, particles were characterized by scanning electron microscopy (SEM), microbeam energy-dispersive X-ray spectroscopy (EDS), inductively coupled plasma mass spectrometry (ICP-MS) and high-performance liquid chromatography (HPLC). A rat model of PM_2.5 exposure was established by nonsurgical intratracheal instillation, and the effects of biochanin A (BCA) treatment were examined. BCA showed a protective effect; it reduced PM_2.5-induced apoptosis and the production of proinflammatory factors, such as tumor necrosis factor-α (TNF-α), interleukin-2 (IL-2), interleukin-6 (IL-6), and the chemokine interleukin-8 (IL-8), as measured using ELISA. These effects were accompanied by increases in the levels of antioxidant enzymes and decreases in the levels of malondialdehyde (MDA), lactate dehydrogenase (LDH) and alkaline phosphatase (AKP). Furthermore, isobaric tag for relative and absolute quantitation (iTRAQ)-based analytical techniques and bioinformatics tools were used to identify putative biomarkers, including XRCC1, MP2K5, IGJ, and F1LQ12, and the results were verified by Western blot analysis. In conclusion, our findings have scientific significance for the application of flavonoids in preventive and therapeutic strategies for PM_2.5-associated pulmonary diseases and for the promotion of human health.

流行病学研究表明，空气动力学直径小于2.5μm（PM _2.5）的颗粒物与人类健康问题密切相关，尤其是诸如慢性阻塞性肺病（COPD），哮喘和肺癌等肺部疾病。在这项研究中，通过扫描电子显微镜（SEM），微束能量色散X射线光谱（EDS），电感耦合等离子体质谱（ICP-MS）和高效液相色谱（HPLC）对颗粒进行了表征。通过非手术气管内滴注建立了PM _2.5暴露的大鼠模型，并检查了生物chanin A（BCA）治疗的效果。BCA显示出保护作用；减少了PM _2.5诱导的细胞凋亡和促炎因子的产生，例如肿瘤坏死因子-α（TNF-α），白介素-2（IL-2），白介素-6（IL-6）和趋化因子白介素-8（IL- 8），如使用ELISA测量的。这些作用伴随着抗氧化酶水平的增加和丙二醛（MDA），乳酸脱氢酶（LDH）和碱性磷酸酶（AKP）的水平降低。此外，基于等压定量的基于相对和绝对定量（iTRAQ）的分析技术和生物信息学工具被用于鉴定推定的生物标记，包括XRCC1，MP2K5，IGJ和F1LQ12，并通过蛋白质印迹分析验证了结果。总之，我们的发现对于黄酮类化合物在PM _2.5的预防和治疗策略中的应用具有科学意义。-相关的肺部疾病，并促进人类健康。