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目的:探讨丁苯酞对血管性痴呆(vascular dementia，VD)小鼠认知功能及Nrf2/SIRT3信号通路中的调节作用。方法:将36只野生型小鼠(Nrf2n ＋/＋)按照随机数字表法分为假手术组(Sham组)、模型组(Nrf2n ＋/＋VD组)、丁苯酞治疗组(Nrf2n ＋/＋NBP组)，每组12只。将24只Nrf2基因敲除小鼠(Nrf2n -/-)按照随机数字表法分为Nrf2n -/-模型组(Nrf2n -/-VD组)和Nrf2n -/-治疗组(Nrf2n -/-NBP组)，每组12只。采用反复三次结扎小鼠双侧颈总动脉的方法建立脑缺血再灌注致认知功能障碍的小鼠模型；应用Morris水迷宫实验检测小鼠的认知功能，HE染色观察海马CA1区神经元形态结构的变化，免疫组化分析小鼠海马CA1区caspase-3、caspase-9的阳性表达，Western blot检测小鼠海马Nrf2、p62、LC3、SIRT3的蛋白表达。n 结果:(1) Morris水迷宫实验中：与VD组小鼠相比，Sham组与Nrf2n ＋/＋NBP组小鼠第5天逃避潜伏期明显缩短[(20.69±8.91)s，(7.58±9.47)s，(8.41±12.20)s；n q＝3.58，5.07，均n P<0.05]，目标象限停留时间百分比明显增加[(16.80±3.27)%，(25.25±5.51)%，(24.18±6.46)%;n q＝3.36，4.43，均n P<0.05]；与VD组比较，Nrf2n -/-VD组小鼠第5天逃避潜伏期明显延长[(33.71±9.05)s]，目标象限停留时间百分比明显降低[(10.84±3.26)%]，均差异有统计学意义(n q＝3.56，3.58；均n P0.05)。(2)病理学结果显示：与VD组小鼠比较，Sham组与Nrf2n ＋/＋NBP组小鼠海马CA1区锥体神经元形态结构损伤更轻，Nrf2n -/-VD组的损伤更为严重，且经NBP治疗后神经元形态改善并不明显。(3)凋亡蛋白的表达：与VD组相比，Sham组与Nrf2n ＋/＋NBP组小鼠海马CA1区caspase-3、caspase-9表达均降低(n t＝3.48，2.95，3.46，2.93，均n P<0.01)，而Nrf2n -/-VD组的表达均增加(n t＝－2.99，－3.77，均n P0.05)。(4)Western blot结果显示：与VD组相比，Nrf2n ＋/＋NBP组小鼠海马Nrf2、SIRT3、p62蛋白表达增加，LC3Ⅱ/Ⅰ比值降低(n t＝－3.24，－4.04，－4.03，3.62，均n P<0.01)；Sham组Nrf2表达、LC3Ⅱ/Ⅰ比值降低，SIRT3、p62表达增加(n t＝3.44，4.72，－3.92，－4.19，均n P<0.01)；Nrf2n -/-VD组Nrf2、SIRT3、p62蛋白表达降低，LC3Ⅱ/Ⅰ比值升高(n t＝9.14，4.20，4.30，－3.78，均n P<0.01)；同Nrf2n -/-NBP比较，Nrf2n -/-VD组Nrf2、SIRT3、p62蛋白表达降低，LC3Ⅱ/Ⅰ比值升高(n t＝2.40，3.24，1.21，－1.16，均n P<0.01)；Nrf2n ＋/＋NBP组Nrf2、SIRT3、p62蛋白表达升高，LC3Ⅱ/Ⅰ比值降低(n t＝－3.29，－5.00，－7.12，6.24，均n P<0.01)。n 结论:丁苯酞可以减轻VD小鼠海马区的凋亡损伤，改善反复缺血再灌注损伤所致的认知功能障碍，其机制可能与调控Nrf2/SIRT3通路、抑制海马区神经细胞凋亡、自噬有关。“,”Objective:To investigate the effects of butylphthalide(NBP) on cognitive function and Nrf2 / SIRT3 signal pathway in vascular dementia (VD) mice.Methods:Wild-type mice (Nrf2n + /+ ) were divided into sham group, model group (VD group), butylphthalide treatment group (Nrf2n + /+ NBP group), and Nrf2 gene knockout mice (Nrf2n -/-) were divided into Nrf2n -/-model group (Nrf2n -/-VD group) and Nrf2n -/-treatment group (Nrf2n -/-NBP group). Both the model group and the treatment group were repeated.The bilateral common carotid arteries were ligated three times to establish a mouse model of cognitive dysfunction caused by cerebral ischemia-reperfusion.The sham group only isolated the bilateral common carotid arteries and threaded the wires, but did not block blood flow.Morris water maze experiment was used to analyze the cognitive function of mice.HE staining was used to observe the changes of neuron morphology and structure in CA1 region of hippocampus, and immunohistochemical analysis was used to analyze the positive expression of caspase 3 and caspase 9 in mouse CA1 region of hippocampus.Western blot was used to detect mouse hippocampus Nrf2, p62, LC3, SIRT3 protein expression.n Results:(1) In Morris water maze experiment: compared with VD group, the escape latency of Sham group and Nrf2n + /+ NBP group was significantly shorter on the 5th day ((20.69±8.91) s, (7.58±9.47)s, (8.41±12.20)s; n q=3.58, 5.07, both n P<0.05), and the percentage of stay time in target quadrant was significantly increased ((16.80±3.27)%, (25.25±5.51)% and (24.18±6.46)%;n q=3.36, 4.43, both n P<0.05). Compared with VD group, the escape latency of Nrf2n -/- VD group was significantly prolonged on the 5th day ((33.71±9.05) s), and the percentage of stay time in target quadrant was significantly reduced ((10.84±3.26)%)(n q=3.56, 3.58; both n P0.05). (2) Pathological results showed that, compared with VD group, the damage of pyramidal neurons in CA1 area of hippocampus in Sham group and Nrf2n + /+ NBP group was lighter, and that in Nrf2n -/- VD group was more serious, and the improvement of neuron morphology was not obvious after NBP treatment.(3) The expression of apoptosis: compared with VD group, the expression of caspase-3 and caspase-9 in the CA1 area of hippocampus in Sham group and Nrf2n + /+ NBP group were significantly lower, and those in Nrf2n -/-VD group were significantly higher (n t=3.48, 2.95, 3.46, 2.93, -2.99, -3.77, all n P0.05). (4) Expression of related proteins: compared with VD group, Nrf2, SIRT3, p62 protein expression increased, LC3II/I ratio decreased in Nrf2n + /+ NBP group(n t=-3.24, -4.04, -4.03, 3.62, all n P<0.01); Nrf2, LC3II/ I ratio decreased, SIRT3, p62 protein expression increased in Sham group(n t=3.44, 4.72, -3.52, -4.19, all n P<0.01); Nrf2, SIRT3, p62 protein expression decreased and LC3II/I ratio increased in Nrf2n -/-VD group(n t=9.14, 4.20, 4.30, -3.78, all n P<0.01); Compared with Nrf2n -/- NBP, the expression of Nrf2, SIRT3, p62 decreased, and LC3II/I ratio increased in Nrf2n -/-VD group(n t=2.40, 3.24, 1.21, -1.16, all n P<0.01). The expression of Nrf2, SIRT3, p62 protein in Nrf2n + /+ NBP group increased, and the ratio of LC3II/ I decreased (n t=-3.29, -5.00, 6.24, all n P<0.01).n Conclusion:Butylphthalide can reduce the apoptotic damage in hippocampus of VD mice and improve cognitive dysfunction caused by repeated ischemia-reperfusion injury.Regulating Nrf2 / SIRT3 pathway to inhibit hippocampal neuronal apoptosis and autophagy may be its role mechanism.