Involvement of PM2.5-bound protein and metals in PM2.5-induced allergic airway inflammation in mice

Abstract

Background: The aim of this study was to investigate the protein and trace element components of PM2.5 and their contribution to the allergic airway inflammation in BALB/c mice.

Methods: PM2.5, treated at high temperature and with a strong acid to hydrolyze any protein content and remove trace elements, was administered to BALB/c mice. Allergic airway inflammation was compared between the three groups (saline, pure PM2.5 and treated PM2.5) by evaluating airway hyperresponsiveness (AHR), bronchoalveolar lavage fluid (BALF) cells, serum IgE, the mRNA of various cytokine (IL-4, IL-5, IL-13, eotaxin-1 and CXCL3), mucus protein mRNA (MUC5ac and MUC5b) and the filtration of inflammatory cells in the lung.

Results: The treatment of PM2.5 with a strong acid at a high temperature attenuated AHR, eosinophil percentage in BALF, mRNA levels of IL-13 and CXCL3 and peribronchial inflammation. On the contrary, the percentage of neutrophils in BALF, mRNA expression of MIP2α, EGFR, Nrf2, and TLR4 and 4-OH-2-nonenal levels in the lung was increased. Moreover, the treatment of the PM2.5 reduced PM2.5-bound proteins as well as the percentages of the trace elements in PM2.5 in the order Zn?>?Cu?> Pb?>?P?>?S?>?Mn?>?Fe?>?Ca?>?Ni, whereas the percentage of C, Si and Cl increased.

Conclusions: PM2.5 collected by of the cyclone system induced allergic airway inflammation in mice. PM2.5-bound proteins and acid-soluble metals may be involved in the pathogenesis of PM2.5-induced allergic airway inflammation.     

Human albumin augmented airway inflammation induced by PM2.5 in NC/Nga mice

The synergic allergic inflammatory effects of particulate matter (PM) 2.5 and human albumin were investigated in NC/Nga mice, which are hypersensitive to mite allergens. PM2.5 or PM2.5 plus human albumin with aluminum oxide was injected twice intraperitoneally for sensitization. After 7 days, PM2.5 or PM2.5 plus human albumin was administered five times intranasally to mice for further sensitization. Subsequently, PM2.5 was administered as a challenge on the 11th day. On the 12th day, mice were examined for airway hyperresponsiveness (AHR), bronchoalveolar lavage fluid (BALF) cell count, mRNA expression of Th₁, Th₂ cytokines, chemokines, and mucus proteins (MUC5AC and MUC5B) in the lung tissue and histopathology. Although PM2.5 or human albumin alone did not induce allergic airway inflammation, simultaneous inoculation of PM2.5 and human albumin‐induced airway inflammation showing increase in AHR, total BALF cell numbers, mRNA levels of IL‐13, eotaxin 1, eotaxin 2, and MUC5AC, and anti‐IG against human serum albumin. Inflammation was observed around the bronchus in PM2.5 plus human albumin‐induced lungs. These results demonstrate that PM2.5 can induce allergic airway inflammation through the synergistic action with human albumin in NC/Nga mice.     

PM2.5‐induced airway inflammation and hyperresponsiveness in NC/Nga mice

The allergic inflammatory effects of particulate matter (PM) 2.5, collected with the cyclone system in Yokohama city in Japan, were investigated in NC/Nga mice, which are hypersensitive to mite allergens. PM2.5 with alum was injected intraperitoneally for sensitization. Five days later, 200 μg of PM2.5 in 25 μL of saline was administered to mice intranasally five times for further sensitization. On the 11th day, PM2.5 was administered as a challenge. On the 12th day, mice were examined for airway hyperresponsiveness (AHR), the bronchoalveolar lavage fluid (BALF) cell count, mRNA expression of Th₁, Th₂ cytokines, and metallothioneins in lung tissue, and histopathology. PM2.5 increased AHR, total cell numbers including eosinophils in BALF, and mRNA levels of IL‐5, IL‐22, eotaxin, eotaxin 2, and metallothionein 3. In PM2.5‐induced lungs, inflammation was observed around the bronchus. These results demonstrate that PM2.5 alone, collected with the cyclone system in Yokohama city in Japan, induces asthma‐like airway inflammation. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1047–1054, 2017.     

Differences in allergic inflammatory responses in murine lungs: comparison of PM2.5 and coarse PM collected during the hazy events in a Chinese city

Urban particulate matter (PM) is associated with an increase in asthma. PM2.5 (<PM2.5?μm) and coarse PM (CPM: PM2.5–PM10?μm) were collected from the air in a Chinese city during haze events. The amounts of polycyclic aromatic hydrocarbons (PAHs) were higher in PM2.5 than in CPM. Conversely, microbial elements LPS and β-glucan were much higher in CPM than in PM2.5. Concentrations of Si, Al, Fe, and Ti in CPM were greater than in PM2.5, while Pb, Cu and As concentrations were lower than in PM2.5. When RAW264.7 cells were treated with PM2.5 and CPM, the pro-inflammatory response in the cells was associated with the microbial element levels and attenuated partly by both polymyxin B (PMB) and N-acetylcystein (NAC). The expression of the oxidative stress response gene heme oxygenase1 was associated with PAHs levels. The exacerbating effects of the two-types of PM on murine lung eosinophilia were compared to clarify the role of toxic materials. When BALB/c mice were intratracheally instilled with PM2.5 or CPM (total 0.4?mg)?+?ovalbumin (OVA), both exacerbated lung eosinophilia along with allergy-relevant biological indicators, such as OVA-specific IgE in serum; enhancement of lung pathology when compared with counterpart samples without OVA. The exacerbating effects were greater in microbial element-rich CPM than in organic chemical-rich PM2.5. These results indicate that microbial elements have more potently exacerbating effects on the development of lung eosinophilia than do organic chemicals. In addition, oxidative stress and transition metals might be associated with the exacerbation of this negative effect.     

PM2.5‐induced lung inflammation in mice: Differences of inflammatory response in macrophages and type II alveolar cells

Particulate matter 2.5 (<PM2.5 μm) leads to chronic obstructive pulmonary disease. In this study, biomarkers related to inflammation and oxidative stress in vitro and in vivo experiments were investigated to clarify the PM2.5‐induced lung inflammation mechanisms. In an in vitro study using RAW264.7 cells, PM2.5 caused phosphorylation of nuclear factor‐κB, p38 mitogen‐activated protein kinase and extracellular response kinases, an increase of proinflammatory gene and protein expressions (e.g. monocyte chemotactic protein‐1, tumor necrosis factor‐α). These biomarkers were substantially attenuated by polymyxin B (PMB). PM2.5 induced heme oxygenase‐1 (HO‐1) gene, which was attenuated by N‐ acetylcysteine (NAC). However, the suppressive effects of NAC on inflammatory biomarkers were very weak. In bone marrow‐derived macrophages (BMDMs) of wild‐type BALB/c mice, the effects of PMB and NAC on PM2.5‐induced inflammatory responses were similar to RAW264.7 cells. In BMDMs of MyD88^−/− mice, PM2.5‐induced proinflammatory mediators were substantially more attenuated. PM2.5 caused an increase of proinflammatory gene expressions (interleukin‐6, cyclooxygenase 2) and HO‐1 gene in MLE‐12 cells (mouse alveolar cell line). These biomarkers were substantially attenuated by NAC, but not by PMB. When BALB/c mice were exposed intratracheally to 0.2 mg PM2.5, PM2.5 caused severe lung inflammation, an increase of neutrophils along with proinflammatory mediators in bronchoalveolar lavage fluid. The inflammation was attenuated by NAC, particularly by NAC + PMB, but not by PMB alone. These results indicate that macrophages may act sensitively to lipopolysaccharide (LPS) present in PM2.5 and release proinflammatory mediators via the LPS/MyD88 pathway. However, type II alveolar cells may react sensitively to oxidative stress induced by PM2.5 and cause inflammatory response. Therefore, overall, PM2.5 may cause predominantly oxidative stress‐dependent inflammation rather than LPS/MyD88‐dependent inflammation in type II alveolar cell‐rich lungs. Copyright © 2017 John Wiley & Sons, Ltd.     

Rat lung response to ozone and fine particulate matter (PM2.5) exposures

Exposure to different ambient pollutants maybe more toxic to lung than exposure to a single pollutant. In this study, we discussed the inflammation and oxidative stress responses of rat lung caused by ozone and PM_2.5 versus that of rats exposed to saline, ozone, or single PM_2.5. Wistar rats inhaled 0.8 ppm ozone or air for 4 h and then placed in air for 3 h following intratracheal instillation with 0, 0.2 (low dose), 0.8 (medium dose), 3.2 (high dose) mg/rat PM_2.5 dissolved in sterile saline (0.25 mL/rat), repeated twice per week for 3 weeks, the cumulative doses of PM_2.5 in animals were 1.2, 4.8, and 19.2 mg. Rats were sacrificed 24 h after the last (sixth) exposure. The collected bronchoalveolar lavage fluid (BALF) was analyzed for inflammatory cells and cytokines. Lung tissues were processed for light microscopic and transmission electron microscopic (TEM) examinations. Results showed that total cell number in BALF of PM_2.5‐exposed groups were higher than control (p < 0.05). PM_2.5 instillation caused dose‐trend increase in tumor necrosis factor alpha (TNF‐α), interleukin‐6, lactate dehydrogenase, and total protein of BALF. Exposure to ozone alone only caused TNF‐α significant change in above‐mentioned indicators of lung injury. On the other hand, ozone could enhance PM_2.5‐induced inflammatory changes and pathological characters in rat lungs. SOD and GSH‐Px activities in lung were reduced in PM_2.5‐exposed rats with and without prior ozone exposure compared to control. To determine whether the PM_2.5 and ozone affect endothelium system, iNOS, eNOS, and ICAM‐1 mRNA levels in lung were analyzed by real‐time PCR. These data demonstrated that inflammation and oxidative stress were involved in toxicology mechanisms of PM_2.5 in rat lung and ozone potentiated these effects induced by PM_2.5. These results have implications for understanding the pulmonary effects induced by ozone and PM_2.5. © 2013 Wiley Periodicals, Inc. Environ Toxicol 30: 343–356, 2015.     

Low dose of fine particulate matter (PM2.5) can induce acute oxidative stress,inflammation and pulmonary impairment in healthy mice

Air pollution is associated with morbidity and mortality induced by respiratory diseases. However, the mechanisms therein involved are not yet fully clarified. Thus, we tested the hypothesis that a single acute exposure to low doses of fine particulate matter (PM2.5) may induce functional and histological lung changes and unchain inflammatory and oxidative stress processes. PM2.5 was collected from the urban area of São Paulo city during 24?h and underwent analysis for elements and polycyclic aromatic hydrocarbon contents. Forty-six male BALB/c mice received intranasal instillation of 30 μL of saline (CTRL) or PM2.5 at 5 or 15?μg in 30 μL of saline (P5 and P15, respectively). Twenty-four hours later, lung mechanics were determined. Lungs were then prepared for histological and biochemical analysis. P15 group showed significantly increased lung impedance and alveolar collapse, as well as lung tissue inflammation, oxidative stress and damage. P5 presented values between CTRL and P15: higher mechanical impedance and inflammation than CTRL, but lower inflammation and oxidative stress than P15. In conclusion, acute exposure to low doses of fine PM induced lung inflammation, oxidative stress and worsened lung impedance and histology in a dose-dependent pattern in mice.     

NLRP3 inflammasome activation is associated with PM2.5‐induced cardiac functional and pathological injury in mice

Growing evidences indicate that inflammation induced by PM_2.5 exposure has been considered as a major driving force for the development of cardiovascular diseases. However, the mechanisms underlying PM_2.5‐induced cardiac injury remain unclear. This study aims to investigate the role of NLRP3 inflammasome in PM_2.5‐induced cardiac functional and pathological injury in mice. In this study, BALB/c mice were intratracheally instilled with PM_2.5 suspension (4.0 mg/kg BW) for 5 days to set up a cardiac injury model, which was evaluated by electrocardiogram monitoring, HE and Masson staining. Then, the effects of PM_2.5 on the expression of α‐SMA, NLRP3, IL‐1β, and IL‐18 proteins and the activation of caspase‐1 and IL‐1β were investigated. The results showed that PM_2.5 exposure induced characteristic abnormal ECG changes such as the abnormality of heart rhythm, tachycardia, and T‐wave reduction. Inflammatory cell infiltration and fibrosis were observed in the heart tissues of PM_2.5‐exposed mice. Meanwhile, PM_2.5 exposure increased the expression of α‐SMA. And, NLRP3 activation‐associated proteins of NLRP3, IL‐1β, IL‐18, Cleaved caspase‐1 p10, and Cleaved IL‐1β were upregulated in heart tissue of PM_2.5‐induced mice. In summary, PM_2.5 exposure could induce cardiac functional and pathological injury, which may be associated with the activation of NLRP3 inflammasome.     

阿魏酸对大气细颗粒物PM2.5诱导的小鼠主动脉炎症的干预作用

目的 探讨大气细颗粒物PM2.5对小鼠主动脉Toll样受体（Toll-like receptors,TLRs）信号通路的影响及阿魏酸的干预作用。方法 采用气管滴注方法以10,20 mg·kg^-1的PM2.5处理小鼠,并用40,80 mg·kg^-1的阿魏酸对部分20 mg·kg^-1 PM2.5处理后的小鼠进行治疗。2周后处死小鼠,血液细胞分析仪检测小鼠血液中炎症细胞水平,ELISA检测血清中IL-1β和IL-6的含量,并用荧光定量PCR检测主动脉中IL-1β和IL-6的mRNA水平,Western blot检测各组小鼠主动脉组织中TLR2、TLR4、MyD88、NF-κB p65蛋白的表达,免疫组化技术观察TLR2和TLR4在小鼠主动脉中的水平。结果 PM2.5能提高血液中NEUT、EOS的数量及其在总细胞中的比率,增加血液和主动脉组织中炎症因子IL-1β、IL-6的含量,上调主动脉组织中的TLRs通路相关分子TLR2、TLR4、MyD88、NF-κB p65的表达;而用阿魏酸干预后,血液中白细胞数量、EOS数量、NEUT与EOS的比率明显降低,IL-1β、IL-6水平下降。同时主动脉组织中的TLRs通路相关分子的表达下调。结论 PM2.5可能通过TLRs通路诱导小鼠主动脉炎症的产生,而阿魏酸可能通过抑制TLRs通路相关因子的表达而发挥抑制PM2.5诱导的小鼠主动脉炎症的作用。     

广州城区大气细颗粒物对PC-12细胞IL-8表达的影响

目的 研究广州城区大气细颗粒物(PM2.5)对PC-12细胞IL-8表达的影响,并从p38 MAPK途径探索其作用机制,促进对PM2.5毒性的认识.方法 采集广州城区大气中的PM2.5,对PC-12细胞染毒,设对照组、不同浓度PM2.5组和SB203580+PM2.5组(用20 μ mol/L的SB230580预处理1h后再给予100μg/ml的PM2.5),Trizol法提取RNA用定量PCR法检测细胞IL-8表达情况,RIRP法提取细胞总蛋白,用Western blot法检测p38 MAPK的磷酸化改变.结果 定量PCR检测显示用25、50和100μg/ml的PM2.5染毒后PC-12细胞IL-8表达明显增高;Western blot结果显示PM2.5可磷酸化激活p38 MAPK信号分子,加入p38 MAPK抑制剂SB230580可以抑制PM2.5诱导的IL-8表达.结论 PM2.5可通过p38 MAPK途径诱导PC-12细胞表达细胞因子IL-8,这可能是其导致神经细胞毒性的机制之一.     

Evaluation of micronucleus induction of sand dust storm fine particles (PM(2.5)) in human blood lymphocytes

Sand dust storms are common phenomena in the arid and semi-arid regions. Previous studies have demonstrated that the airborne air fine particulate matter (PM_2.5, particulates with an aerodynamic diameter ≤2.5 μm) and its extracts can induce human genetic damage of lymphocytes such as micronucleus formation, chromosomal aberration and so on. However, little is known about the health risks associated with sand dust storm PM_2.5 and its extracts. The aim of the present study is to investigate the micronucleus induction of sand dust storm PM_2.5 (include its organic and inorganic extract) from two different towns on human lymphocytes. The samples of normal PM_2.5 and sand dust storm PM_2.5 were collected in Wuwei (Gansu Province) and Baotou (Inner Mongolia), China. The cytochalasin-B cytokinesis-block test was employed and the cells were treated with 0, 33, 100, 300 μg ml⁻¹ sand dust storm PM_2.5 or normal ambient air PM_2.5 suspension (physiological saline as solvent control), or inorganic extract (0, 75, 150, 300 μg ml⁻¹, physiological saline as solvent control) or organic extract (0, 20, 40, 80 μg ml⁻¹, DMSO as solvent control) at the beginning of the cell culture. Both sand dust storm and normal PM_2.5 and their extract treatment cultures revealed an increase in the frequency of micronucleus. With the increase of treatment concentrations the frequency of micronucleus increased and the nuclear division index (NDI) values declined in a dose–response manner (P < 0.01). In the same concentrates, the frequency of micronucleus of normal ambient air PM_2.5 and its extract were significant higher than those of sand dust storm PM_2.5 (P < 0.01) except the treatment of Wuwei sample at higher doses, the treatment of inorganic extract of PM_2.5 at the highest dose (300 μg ml⁻¹) and the treatment of organic extract of PM_2.5 at the higher dose (40 and 80 μg ml⁻¹) either in Baotou or in Wuwei (P > 0.05). The toxicity of sand dust storm PM_2.5 and its extract at high dose is very potent. The frequency of micronucleus of normal PM_2.5 (include its organic extract) from Baotou were higher than those of Wuwei especially in low and middle dose (P < 0.05), but the treatment results of sand dust storm PM_2.5 (include its all extract) was not significantly different between the towns (P > 0.05).     

Oxidative stress and endocytosis are involved in upregulation of interleukin‐8 expression in airway cells exposed to PM2.5

Inhaled PM2.5 (particulate matter with an aerodynamic diameter of 2.5 μm or less) can induce lung inflammation through released inflammatory mediators from airway cells, such as interleukin‐8 (IL‐8) and tumor necrosis factor alpha (TNF‐α). However, the mechanisms underlying PM2.5‐induced IL‐8 gene expression have not been fully characterized. BEAS‐2B cells (a human bronchial epithelial cell line) and THP‐1 cells (a human macrophage‐like cell line) were used as the in vitro models to investigate the underlying mechanism in this study. IL‐8 expression was increased in the cells treated with PM2.5 in a dose‐dependent manner. The water‐soluble and insoluble fractions of PM2.5 suspension were both shown to induce IL‐8 expression. PM2.5 exposure could obviously induce ROS (reactive oxygen species) generation, indicative of oxidative stress. Pretreatment with the antioxidant N‐acetyl‐l ‐cysteine (NAC) potently inhibited PM2.5‐induced IL‐8 expression. Employment of the transition metal chelators including TPEN (N,N,N',N'‐tetrakis (2‐pyridylmethyl) ethylenediamine) or DFO (desferrioxamine) inhibited IL‐8 expression induced by PM2.5 by over 20% in BEAS‐2B cells, but had minimal effect in THP‐1 cells. Pretreatment with the endocytosis inhibitor CytD markedly blocked IL‐8 expression induced by PM2.5 in both BEAS‐2B and THP‐1 cells. In summary, exposure to PM2.5 induced IL‐8 gene expression through oxidative stress induction and endocytosis in airway cells. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1869–1878, 2016.     

粤北地区过敏性鼻炎发病率与PM2.5相关性的临床研究

目的分析粤北地区过敏性鼻炎发生率与PM2.5间的关联。方法选取2018年8月~2019年10月粤北地区各医院就诊的过敏性鼻炎患者为研究对象,并收集同期空气数据,分析粤北地区过敏性鼻炎发病率与空气中二氧化硫(SO2)、二氧化氮(NO2)、PM10、PM2.5的相关性。结果950例过敏性鼻炎患者中,2018年发病456例,空气中SO2浓度为0.033 mg/m^2、NO2浓度为0.014 mg/m^2、PM10浓度为0.108 mg/m^2;2019年发病494例,空气中SO2浓度为0.034 mg/m^2、NO2浓度为0.024 mg/m^2、PM10浓度为0.098 mg/m^2。过敏性鼻炎发病率与空气中SO2、NO2、PM10浓度无相关性(r=-0.041、0.064、0.025,P>0.05)。2018年空气中PM2.5含量为0.112 mg/m^2,2019年空气中PM2.5含量为0.361 mg/m^2。过敏性鼻炎发病率与空气中PM2.5浓度呈正相关(r=0.697,P<0.05)。结论改善空气质量,减少空气中PM2.5的浓度,能够有效降低过敏性鼻炎发病率。     

PM2.5通过TLR4破坏自噬流加重Raw264.7巨噬细胞炎症反应

目的 探讨PM_2.5对Raw264.7巨噬细胞自噬及炎症反应的影响及机制。方法 CCK-8检测PM_2.5对Raw264.7巨噬细胞活性的影响,透射电镜观察自噬结构;Ad-mCherry-GFP-LC3B转染细胞后荧光显微镜观察自噬通量,以探讨PM_2.5对巨噬细胞活性和自噬流的影响。再设置对照组、PM_2.5组、雷帕霉素（Rap,自噬诱导剂）组、羟氯喹（HCQ,自噬抑制剂）组、PM_2.5+HCQ组、PM_2.5+TAK-242[Toll样受体4（TLR4）抑制剂]组。Western blot法检测自噬相关蛋白,包括微管相关轻链蛋白3比值（LC3Ⅱ/Ⅰ）、p62、组织蛋白酶B（CTSB）、溶酶体膜蛋白2（LAMP2）和炎症相关蛋白,包括Toll样受体4（TLR4）、核苷酸结合域样受体蛋白3（NLRP3）的表达水平;酶联免疫吸附试验检测相关炎性因子白细胞介素（IL）-1β、IL-18、IL-10分泌水平。结果 Raw264.7巨噬细胞活性随着PM_2.5浓度的增加和作用时间的延长而降低。透射电镜观察到PM_2.5组有较多自噬空泡和双膜自噬体,自噬溶酶体少见,且荧光显微镜下PM_2.5组绿色荧光淬灭不明显,Merge后黄红色荧光比值高于对照组和Rap组（P<0.05）。相较于对照组,PM_2.5组NLRP3、LC3Ⅱ/Ⅰ、p62、CTSB、IL-1β、IL-18的表达上调,LAMP2、IL-10表达下调（P<0.05）,而HCQ抑制自噬的同时,促进NLRP3、IL-1β、IL-18的表达,抑制IL-10表达（P<0.05）。相较于对照组、PM_2.5组和HCQ组,PM_2.5+HCQ组NLRP3、IL-1β、IL-18的上调及IL-10下调更为显著（P<0.05）。此外,PM_2.5组TLR4表达高于对照组,TAK-242抑制TLR4后NLRP3、LC3Ⅱ/Ⅰ、p62、CTSB、IL-1β、IL-18的表达较PM_2.5组下调,LAMP2和IL-10的表达上调（P<0.05）。结论 PM_2.5可呈时间和浓度依赖性地降低巨噬细胞活性;且PM_2.5诱导Raw264.7巨噬细胞发生自噬,但阻断自噬流,加重巨噬细胞炎症反应,且该过程可能由TLR4介导。     

格列美脲对细颗粒物PM2.5诱导的心肌样细胞损伤的保护作用及机制研究

摘 要 目的：探讨格列美脲对细颗粒物空气动力学直径<2.5 μm（PM2.5）诱导的心肌样细胞损伤的保护作用及机制研究。 方法: 采用噻唑蓝（MTT）确定PM2.5的干预浓度;将大鼠心肌样细胞H9c2分为对照组（含血清1640培养基）、PM2.5组（800 mg·L-1）、格列美脲低、中、高剂量组（10,20,40 μmol·L-1的格列美脲＋800 mg·L-1的PM2.5）。培养24 h后检测H9c2细胞中肿瘤坏死因子 α（TNF α）和白细胞介素 1β（IL 1β）含量,同时检测细胞中活性氧（ROS）和细胞凋亡率,检测B淋巴细胞瘤 2（Bcl 2）、Bcl 2 Associated X的蛋白质（Bax）和半胱氨酸天冬氨酸特异性蛋白酶 3（caspase 3）mRNA表达水平。 结果: 随着PM2.5浓度的增加,H9c2细胞增值率降低,在800 mg·L-1时H9c2细胞增值率降到46.28%,故选800 mg·L-1作为PM2.5的干预浓度;与PM2.5组比较,格列美脲各剂量组细胞中TNF α、IL 1β含量、ROS荧光强度、细胞凋亡率、Bax和caspase 3 mRNA的相对表达量显著降低（P<0.05）,Bcl 2 mRNA的相对表达量显著升高（P<0.05）,且呈剂量相关性（P<0.05）。 结论: 格列美脲对细颗粒物PM2.5诱导的心肌样细胞损伤具有保护作用,其机制可能与格列美脲减轻炎症反应和氧化应激、抑制心肌细胞凋亡有关。     

基于转录组测序探究PM2.5损伤肺上皮细胞 BEAS-2B的相关机制

目的 研究 PM2.5 对肺上皮细胞 BEAS-2B 基因表达的影响,并探讨其可能作用的信号通路。方法 BEAS-2B细胞分为对照组（PBS处理）和PM2.5组（200 mg/L PM2.5处理）,干预24 h后提取各组细胞总RNA进行高通 量测序。所得的序列经质控,与参考基因组比对,获得用于后续转录本组装、表达量计算的 mapped data（reads）后,比 对到 6 大数据库［NR、Swiss-Prot、Pfam、COG（Evolutionary genealogy of genes）、GO（Gene Ontology）、KEGG（Kyoto Encyclopedia of Genes and Genomes）］注释,利用差异分析软件DESeq2筛选出差异表达基因（DEGs）,运用生物信息学 分析方法对DEGs进行GO和KEGG生物功能等分析,采用qRT-PCR法检测5个关键基因（FOSB、FOSL1、MUC5AC、 CSF2、IL-6）进行验证。结果 PM2.5组和对照组与转录组的数据比较后共获得961个DEGs,其中PM2.5组上调表达 453个,下调表达508个。通过GO和KEGG功能分析后发现这些DEGs主要参与了细胞蛋白质的磷酸化、免疫调节过 程、信号转导途径的调节以及凋亡途径的调控过程,并显著富集于IL-17信号通路。qRT-PCR结果显示,PM2.5组 FOSB、FOSL1与IL-6的相对表达量显著上调（P＜0.05）,这与RNA-seq测序结果一致。结论 PM2.5可能通过调控 “IL-17信号通路”中关键基因的表达,加重了细胞的炎症反应,促进了细胞凋亡等生命进程。     

Role of iron and oxidative stress in the exacerbation of allergic inflammation in murine lungs caused by urban particulate matter <2.5 μm and desert dust

Simultaneous exposure of lipopolysaccharide (LPS) and urban particulate matter <2.5 μm (PM2.5) or desert dust exacerbated murine asthma. In the present study, the role of iron (Fe) contained in particles and oxidative stress was investigated using Fe chelator deferoxamine (DFO) and oxidative stress scavenger N‐acetylcysteine (NAC) in a murine asthma model exacerbated by LPS + PM2.5 or LPS + Asian sand dust (ASD). When BALB/c mice were intratracheally challenged with ovalbumin (OVA) + LPS and either urban PM2.5 or ASD, LPS + PM2.5 and LPS + ASD caused exacerbation of OVA‐induced lung eosinophilia along with T‐helper 2 cytokine and eosinophil‐relevant chemokine production in bronchoalveolar lavage fluid as well as the production of OVA‐specific IgE in serum. LPS + PM2.5 with NAC tended to reduce the lung eosinophilia compared to the LPS + PM2.5 host, whereas LPS + PM2.5 with DFO did not reduce them. LPS + ASD with NAC moderately reduced the lung eosinophilia compared to the LPS + ASD host. LPS + ASD with DFO drastically reduced the lung eosinophilia compared to the LPS + ASD host. The concentration of Fe in urban PM2.5 and ASD were almost the same. However, the concentrations of trace metals Pb, Cu, As, Ni, Cr, Mo, Sb, Co, Se and Cd were greater in PM2.5 than in ASD. These results suggested that Fe and oxidative stress are at least partly involved in lung eosinophilia exacerbation caused by LPS + ASD. However, trace metals (except Fe) might also be involved in lung eosinophilia exacerbated by LPS + PM2.5.     

Effects of Astragalus and Codonopsis pilosula polysaccharides on alveolar macrophage phagocytosis and inflammation in chronic obstructive pulmonary disease mice exposed to PM2.5

Astragalus and Codonopsis pilosula are used for their immunomodulatory and anti-inflammatory effects. Here, we investigated the effects of Astragalus polysaccharides (APS) and Codonopsis pilosula polysaccharides (CPP) on alveolar macrophage (AM) phagocytosis and inflammation in chronic obstructive pulmonary disease (COPD) associated with exposure to particulate matter with a mean aerodynamic diameter ≤2.5 μm (PM2.5). A mouse model of COPD was established by cigarette smoke exposure. PM2.5 exposure was performed by inhalation of a PM2.5 solution aerosol. APS and CPP were administered intragastrically. COPD showed defective AM phagocytosis and increased levels of interleukin (IL)-6, IL-8, and tumor necrosis factor (TNF)-α in bronchoalveolar lavage fluid and serum. PM2.5 exposure aggravated the damage, and this effect was reversed by APS and CPP gavage. The results indicate that APS and CPP may promote defective AM phagocytosis and ameliorate the inflammatory response in COPD with or without PM2.5 exposure.     

用差热分析法测定固体药物马来酸罗格列酮热降解稳定性

采用差热分析 (DTA)的方法研究了固体药物马来酸罗格列酮的分解反应动力学 ,用Kissinger方程计算求得该药物的热分解动力学参数。结果得到马来酸罗格列酮的热分解反应级数为一级 ;热分解反应活化能E为 12 7 7kJ/mol;频率因子A为 2 0 4× 10 8S-1;相关系数为0 992 5。