The effects of inhalation of diesel exhaust on murine mycobacterial infection
The effects of inhalation of diesel exhaust on murine mycobacterial infection
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DOI：
10.1080/01902140590918786
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发表时间：
2005-05-01
影响因子：
1.7
通讯作者：
Sugawara, I
中科院分区：
文献类型：
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作者：
Hiramatsu, K;Saito, Y;Sugawara, I
作者研究了吸入柴油机尾气（DE）对小鼠体内分枝杆菌感染的影响。将8周龄雌性BALB/c小鼠暴露于DE（3 mg/m3柴油机排气颗粒[DEP]）1个月、2个月或6个月（每天7小时，每周5天）。将对照小鼠在洁净室中饲养相同时间。在最后一次接触DE的第二天，对照小鼠和接触DE的小鼠在空气中感染结核分枝杆菌（1 x 10（6）菌落形成单位（CFU），Kurono菌株）。在分枝杆菌感染后7周，作者检查了肺组织的组织病理学变化，并进行了逆转录酶-聚合酶链反应（RT-PCR），以测量几种促炎细胞因子和诱导型一氧化氮合酶（iNOS）的信使RNA（mRNA）表达。然后，将肺和脾的匀浆在1%（v/v）Ogawa’s egg slide培养基上培养，并在37 ℃下孵育4周后，对培养基上的菌落进行计数。DE暴露1个月后，分枝杆菌感染略有改善。DE暴露2个月后，肿瘤坏死因子（TNF）-α、白细胞介素（IL）-1 β、IL-12 p40、干扰素（IFN）-γ和iNOS mRNA的表达水平略有增加。然而，在DE暴露6个月后，IL-1 β、IL-12 p40、IFN-γ和iNOS mRNA的表达水平降低，并且通过增加的肺负荷（CFU）测量的感染实际上增加。这些结果表明，长期DE暴露可能会增加肺分枝杆菌负荷。
The authors investigated the effects of inhalation of diesel exhaust ( DE) on murine mycobacterial infection in vivo. Eight-week-old female BALB/c mice were exposed to DE ( 3 mg/m(3) of diesel exhaust particles [DEPs]) for 1 month, 2 months, or 6 months ( for 7 hours a day, 5 days a week). Control mice were housed in a clean room for the same periods. On the day following the last DE exposure, control mice and DE-exposed mice were aerially infected with Mycobacterium tuberculosis ( 1 x 10(6) colony-forming units (CFU), Kurono strain). At 7 weeks after mycobacterial infection, the authors examined the lung tissues for histopathological changes and performed reverse transcriptase - polymerase chain reaction (RT-PCR) to measure the messenger RNA ( mRNA) expression of several proinflammatory cytokines and inducible nitric oxide synthase ( iNOS). Then, the homogenates of lungs and spleens were cultured on 1% (v/v) Ogawa's egg slant medium, and after a 4-week incubation period at 37 degrees C, colonies on the medium were counted. After 1 month of DE exposure, the mycobacterial infection had slightly ameliorated. After 2 months of DE exposure, the expression levels of tumor necrosis factor (TNF)-alpha, interleukin (IL)-1 beta, IL-12p40, interferon (IFN)-gamma, and iNOS mRNAs were slightly increased. However, after 6 months of DE exposure, the expression levels of IL-1 beta, IL-12p40, IFN-gamma, and iNOS mRNAs were decreased, and the infection as measured by increased lung burden ( CFU) actually increased. These results indicate that long-term DE exposure may increase pulmonary mycobacterial burden.