Repeated intra-nigrostriatal injection of phorbol myristate acetate induces microglial senescence in adult rats.
Repeated intra-nigrostriatal injection of phorbol myristate acetate induces microglial senescence in adult rats.
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黑质纹状体内重复注射佛波醇肉豆蔻酸酯醋酸酯诱导成年大鼠小胶质细胞衰老
DOI：
10.3892/mmr.2015.4412
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发表时间：
2015-11
影响因子：
3.4
通讯作者：
He ZY
中科院分区：
文献类型：
--
作者：
Liu L;Luo XG;Yu HM;Feng Y;Ren Y;Yin YF;Shang H;He ZY
佛波醇肉豆蔻酸酯（PMA）作为一种强有力的肿瘤促进剂，可诱导小胶质细胞衰老。本研究探讨PMA感染对小胶质细胞衰老的影响。从58只雄性Sprague-Dawley大鼠中随机选择10只，分为PMA注射组（含5只大鼠，0.5 μg/μl PMA）和对照组（含5只大鼠，可稀释的0.9%生理盐水）。采用免疫荧光法检测Iba-1的表达，酶联免疫吸附法检测肿瘤坏死因子（TNF）-α和白细胞介素（IL）-1 β的表达。其余48只大鼠随机分为以下3组，每组16只：重复注射对照组（生理盐水，每周1次，共4周）、单次注射PMA组（0.5 μg/μl PMA，第1周1次）和重复注射PMA组（0.5 μg/μ l PMA，每周1次，共4周）。采用Iba-1免疫荧光双标法检测p21蛋白的表达，采用Iba-1免疫组织化学双标法检测β-半乳糖苷酶的表达。结果表明，与对照组相比，PMA单次注射对小胶质细胞形态无明显影响，对TNF-α和IL-1β的表达水平无明显影响（P>0.05）。4次注射PMA后，黑质小胶质细胞呈现衰老特征，β-半乳糖苷酶（P<0.001）和p21（P<0.001）表达水平较对照组明显升高。总之，PMA重复黑质纹状体内处理诱导大鼠黑质小胶质细胞衰老，β-半乳糖苷酶和p21表达水平增加。
Phorbol myristate acetate (PMA), as a potent tumor promoter, may induce microglial senescence. The present study investigated the effect of PMA infection on microglial senescence. From 58 male Sprague-Dawley rats, 10 were randomly selected and divided into a PMA injection group, containing five rats (0.5 µg/µl PMA) and a control group, containing five rats (commensurable 0.9% saline). Immunofluorescent staining of Iba-1 and enzyme-linked immunosorbent assay analyses of the expression levels of tumor necrosis factor (TNF)-α and interleukin (IL)-1 β were performed in these two groups. The remaining 48 rats were randomly divided into the following three groups, each containing 16 rats: Repeated injection control group (commensurable normal saline, once a week for 4 weeks), single PMA injection group (0.5 µg/µl PMA, once in the first week) and repeated injection PMA group (0.5 µg/µl PMA, once a week for 4 weeks). The expression levels of p21, detected using double immunofluorescence staining with Iba-1, and β-galactosidase, via double immunohistochemical staining of Iba-1, were examined in these three groups. The results indicated that a single injection of PMA did not change the microglial morphology and had no significant effects on the expression levels of TNF-α and IL-1β, compared with the control group (P>0.05). Following four repeated injections of PMA, the microglia in the substantia nigra presented with features of senescence, characterized by increased expression levels of β-galactosidase (P<0.001) and p21 (P<0.001), compared with the repeated injection control group. In conclusion, repeated intra-nigrostriatal treatment with PMA induced microglial senescence with increased expression levels of β-galactosidase and p21 in the substantia nigra of the rats.