Chen Gang, Shi Jixin, Jin Wei, Wang Lin, Xie Weiying, Sun Jie, Hang Chunhua
Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, Jiangsu Province, PR China.
Ann Clin Lab Sci. 2008 Winter;38(1):65-74.
This study investigated whether progesterone administration modulates toll-like receptors (TLRs) and the nuclear factor-kappa B (NF-kappaB) signaling pathway in the injured rat brain following traumatic brain injury (TBI). Right parietal cortical contusion was made by a weight-dropping method. Male rats were given 0 or 16 mg/kg injections of progesterone at postinjury hr 1 and 6 and on days 1, 2, 3, 4, and 5. Brain samples were extracted at 5 days after trauma. We measured mRNA expression of TLR2 and TLR4 by reverse-transcriptase polymerase chain reaction (RT-PCR), NF-kappaB binding activity by electrophoretic mobility shift assay (EMSA), concentrations of interleukin-1 beta (IL-1 beta), tumor necrosis factor-alpha (TNF-alpha), and interleukin-6 (IL-6) by enzyme-linked immunosorbent assay (ELISA), intercellular adhesion molecule-1 (ICAM-1) expression by immunohistochemistry, and brain damage by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL). The results showed that TBI induces strong up-regulation of TLR2, TLR4, NF-kappaB, pro-inflammatory cytokines, and ICAM-1 in the pericontusional area. Administration of progesterone following TBI down-regulates the cortical levels of these agents related to the TLRs/NF-kappaB signaling pathway. After progesterone administration, apoptotic TUNEL-positive cells in the injured brain were significantly decreased. In summary, post-TBI progesterone administration attenuates the TLRs/NF-kappaB signaling pathway in injured rat brain, and this may be a mechanism whereby progesterone improves the outcome following TBI.
本研究调查了创伤性脑损伤（TBI）后，给予孕酮是否能调节受伤大鼠脑中的Toll样受体（TLRs）和核因子-κB（NF-κB）信号通路。采用重物坠落法造成右侧顶叶皮质挫伤。雄性大鼠在伤后1小时和6小时以及第1、2、3、4和5天分别注射0或16mg/kg的孕酮。在创伤后5天提取脑样本。我们通过逆转录聚合酶链反应（RT-PCR）测量TLR2和TLR4的mRNA表达，通过电泳迁移率变动分析（EMSA）测量NF-κB结合活性，通过酶联免疫吸附测定（ELISA）测量白细胞介素-1β（IL-1β）、肿瘤坏死因子-α（TNF-α）和白细胞介素-6（IL-6）的浓度，通过免疫组织化学测量细胞间黏附分子-1（ICAM-1）的表达，并通过末端脱氧核苷酸转移酶介导的dUTP缺口末端标记（TUNEL）测量脑损伤。结果表明，TBI可诱导挫伤周围区域的TLR2、TLR4、NF-κB、促炎细胞因子和ICAM-1强烈上调。TBI后给予孕酮可下调与TLRs/NF-κB信号通路相关的这些因子的皮质水平。给予孕酮后，受伤脑中凋亡的TUNEL阳性细胞显著减少。总之，TBI后给予孕酮可减弱受伤大鼠脑中的TLRs/NF-κB信号通路，这可能是孕酮改善TBI后预后情况的一种机制。
