bFGF对颅脑损伤大鼠脑水肿、神经功能损伤及自噬相关蛋白表达的影响

摘要

AIM:To study the effects of basic fibroblast growth factor (bFGF) on brain edema, nerve function damage and autophagy related proteins in rats with head injury.METHODS:The rat model of craniocerebral injury (CI) was constructed.The rats were divided into control group, CI group, and low-, middle-and high-dose bFGF groups (n=10).The CI model was established in CI group, while the rats in control group were not given epidural impact.The rats in low-dose, middle-dose and high-dose bFGF groups were given bFGF at 2, 4 and 6μg, respectively, by intraperitoneal injection after 30 min.The neurological function in the rats was evaluated by improved neurological function scoring.The rat brain tissues were taken, and the water content was detected.The levels of tumor necrosis factor-α (TNF-α) , interleukin-6 (IL-6) and IL-1βin the brain tissue were measured by ELISA.The malondialdehyde (MDA) content was analyzed by thiobarbituric acid method.The activity of superoxide dismutase (SOD) was examined by WST-8 assay.The glutathine peroxidase (GSH-Px) activity was detected by colorimetric method.The protein levels of autophagy related proteins LC3-II and beclin-1 in the brain tissues were determined by Western blot.RESULTS:The neurological function score was increased significantly of the rats in CI group.The rat model of craniocerebral injury was successfully constructed.Neurological function scores in the rats in low-dose, middle-dose and high-dose bFGF groups were reduced, the water content of the brain tissue was also reduced (P<0.05).The levels of TNF-α, IL-6 and IL-1βwere decreased in the brain tissues (P<0.05) , the content of MDA was declined (P<0.05) , the activities of SOD and GSH-Px were increased (P<0.05) , the protein levels of LC3-II and beclin-1 were decreased, compared with the untreated rats in CI group (P<0.05).CON-CLUSION:bFGF improves the nerve function of the rats with craniocerebral injury, reduces the water content of the brain tissue, reduces the expression of autophagic protein LC3-II and beclin-1.The mechanism is related to the inhibition of inflammatory reaction and oxidative damage.%目的:研究碱性成纤维细胞生长因子 (bFGF) 对颅脑损伤 (CI) 大鼠脑水肿、神经功能损伤及自噬相关蛋白表达影响.方法:采用Feeney's自由落体硬膜外撞击法构建大鼠颅脑损伤模型, 成年雄性SD大鼠随机分为对照 (control) 组、CI组及bFGF低、中和高剂量组, 每组10只;对照组不给予硬膜外撞击, 其它处理同模型组;bFGF低、中和高剂量组在建模成功30 min后分别给予2、4和6μg的bFGF腹腔注射, 连续注射7 d.用改良神经功能评分法对大鼠神经功能进行评分.取大鼠脑组织, 测定大鼠脑组织含水量, ELISA法测定脑组织中肿瘤坏死因子α (TNF-α) 、白细胞介素6 (IL-6) 和白细胞介素1β (IL-1β) 含量, 硫代巴比妥酸法测定丙二醛 (MDA) 含量, WST-8法检测超氧化物歧化酶 (SOD) 活性, 比色法检测谷胱甘肽过氧化物酶 (GSH-Px) 活性, Western blot法测定脑组织中自噬相关蛋白LC3-Ⅱ和beclin-1的水平.结果:与control组相比, CI组神经功能评分明显升高 (P <0.05) ;与CI组相比, bFGF低、中和高剂量组大鼠神经功能评分降低, 脑组织含水量也降低 (P <0.05) , 脑组织中TNF-α、IL-6和IL-1β水平降低 (P <0.05) , MDA含量降低 (P <0.05) , SOD和GSH-Px活性升高 (P <0.05) , LC3-Ⅱ和bec-lin-1蛋白水平降低 (P <0.05) .结论:bFGF能够改善颅脑损伤大鼠神经功能, 降低脑组织含水量, 减少自噬相关蛋白LC3-Ⅱ和beclin-1的表达, 这可能与其减轻炎症反应及氧化损伤有关.