目的 探討五味子甲素對血管性癡呆（VD）大鼠沉默信息調(diào)節(jié)因子1/過氧化物酶體增殖物激活受體γ輔助激活因子-1α（SIRT1/PGC-1α）通路及海馬神經(jīng)元凋亡的影響。方法 50只大鼠雙側(cè)頸總動脈永久性結(jié)扎法制備VD模型，造模大鼠按照隨機(jī)數(shù)字表法分為模型組、五味子甲素（20、40、80 mg/kg）組、陽性對照組，每組10只；另取10只大鼠不結(jié)扎左右頸總動脈近端、遠(yuǎn)端，其余處理相同，為假手術(shù)組。五味子甲素（低、中、高）劑量組分別ip 20、40、80 mg/kg五味子甲素，陽性對照組ig 0.54 g/kg甲磺酸雙氫麥角毒堿片，假手術(shù)組和模型組ip等體積溶媒，1次/d，連續(xù)21 d。Morris水迷宮實驗評估大鼠空間探索能力；蘇木精-伊紅（HE）染色觀察海馬區(qū)神經(jīng)元形態(tài)；脫氧核糖核苷酸末端轉(zhuǎn)移酶介導(dǎo)的缺口末端標(biāo)記法（TUNEL）檢測海馬區(qū)神經(jīng)元凋亡情況；蛋白免疫印跡檢測大鼠海馬區(qū)B淋巴細(xì)胞瘤-2基因（Bcl-2）、Bcl-2相關(guān)X蛋白（Bax）、半胱氨酸天冬氨酸蛋白酶-3（Caspase-3）、活化的Caspase-3（cleaved Caspase-3）、SIRT1、PGC-1α蛋白表達(dá)水平。結(jié)果 模型組大鼠海馬區(qū)細(xì)胞形態(tài)不規(guī)則或紡錘形，胞質(zhì)和核濃縮、出現(xiàn)神經(jīng)元凋亡情況；五味子甲素（低、中、高）劑量組隨著劑量的增加，神經(jīng)元凋亡情況逐漸緩解，且高劑量組幾乎觀察不到凋亡神經(jīng)元。與假手術(shù)組相比，模型組大鼠海馬區(qū)神經(jīng)元凋亡比例、海馬區(qū)Bax、cleaved Caspase-3/Caspase-3蛋白水平升高，平臺象限停留時間、穿越平臺次數(shù)減少，海馬區(qū)Bcl-2、SIRT1、PGC-1α蛋白水平降低（P<0.05）。與模型組相比，五味子甲素（中、高）劑量組大鼠海馬區(qū)神經(jīng)元凋亡比例、海馬區(qū)Bax、cleaved Caspase-3/Caspase-3蛋白水平降低，平臺象限停留時間、穿越平臺次數(shù)增加，海馬區(qū)Bcl-2、SIRT1、PGC-1α蛋白水平升高（P<0.05）；五味子甲素低劑量組平臺象限停留時間增加，海馬區(qū)神經(jīng)元凋亡比例、Bax、cleaved Caspase-3/Caspase-3蛋白水平降低，Bcl-2蛋白水平升高（P<0.05）。結(jié)論 五味子甲素可以抑制VD大鼠海馬神經(jīng)元凋亡情況，可能是通過激活SIRT1/PGC-1α通路實現(xiàn)的。

Objective To investigate the effects of schisandrin A on silent mating type information regulation 2 homolog 1/peroxisome proliferator-activated receptor γ coactivator-1α (SIRT1/PGC-1α) pathway and apoptosis of hippocampal neurons in vascular dementia (VD) rats.Methods The VD model was established by permanent ligation of bilateral common carotid arteries in 50 rats, the model rats were divided into model group, schisandrin A (low, medium and high) dose groups and positive control group according to the random number table, with 10 rats in each group. Another 10 rats were given the same treatment as the sham operation group, except that the proximal and distal ends of the left and right common carotid arteries were not ligated. schisandrin A (low, medium and high) dose groups were intraperitoneally injected with 20, 40, 80 mg/kg schisandrin A respectively, and the positive control group was intragastrically administered with 0.54 g/kg dihydroergotoxine mesylate tablets, and the sham operation group and model group were intraperitoneally injected with the same volume of solvent, once a day for 21 days. Morris water maze test was used to evaluate space exploration, the hippocampal neurons were detected by hematoxylin eosin (HE), the apoptosis of hippocampal neurons was detected by terminal dexynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL), Western blotting was used to detect the levels of B-lymphoma-2 gene (Bcl-2), Bcl-2-associated X protein (Bax), Caspase-3, activated Caspase-3 (cleaved Caspase-3), SIRT1, PGC-1α protein.Results In the model group, the morphology of the hippocampal neurons were irregular or spindle shaped, the cytoplasm and nucleus were concentrated, and neuron apoptosis was observed, with the increase of schisandrin A (low, medium, and high) dose groups, the apoptosis of neurons gradually alleviated, and almost no apoptotic neurons were observed in the high dose group. Compared with those in the sham operation group, the apoptosis ratio of hippocampal neurons and the levels of Bax and cleaved Caspase3/Caspase-3 protein in the model group were higher, the time to stay on the platform quadrant and the time of crossing the platform were more, and the protein levels of Bcl-2, SIRT1 and PGC-1α in hippocampus were lower (P<0.05). Compared with those in the model group, the apoptosis ratio of hippocampal neurons and the levels of Bax and cleaved Caspase3/Caspase-3 protein in the schisandrin A (medium and high) dose groups were lower, the time to stay on the platform quadrant and the times of crossing the platform were less, and the protein levels of Bcl-2, SIRT1 and PGC-1α in hippocampus were higher (P<0.05), the time spent on the platform in the schisandrin A low dose groups was less, the apoptosis ratio of hippocampal neurons and the levels of Bax and cleaved-caspase3/caspase3 protein were lower, and the protein level of Bcl-2 was higher (P<0.05).Conclusion Schisandrin A can inhibit the apoptosis of hippocampal neurons in VD rats, which may be realized by activating SIRT1/PGC-1α pathway.

R285.5

國家自然科學(xué)青年科學(xué)基金資助項目（81904264）