花旗松素对β-淀粉样肽损伤神经元的保护作用及机制

Neuroprotective Effects and Mechanism of Taxifolin Against Neural Damage Induced by Aβ

摘要:

目的: 研究花旗松素对 β-淀粉样肽(β-amyloid peptide,Aβ)损伤神经元的保护作用及其机制. 方法: 从新生乳鼠大脑皮层中分离纯化神经元,与Aβ(5 μmol·L^-1)、不同浓度花旗松素(20~100 μmol·L^-1)共同孵育24 h,CCK8法检测细胞存活率,Hoechst 33258染色和Annexin V-FITC/PI检测细胞凋亡,分光光度法检测半胱天冬酶-3(caspase-3)活性的变化. 结果: 在细胞活力实验中,与正常组相比,模型组细胞活力显著下降(49.2±1.3) %,不同浓度的花旗松素可以提高神经元活力,其中80 μmol·L^-1花旗松素给药组细胞活力增至(68.7±3.2) %,与模型组相比有极显著差异;细胞凋亡结果显示,与正常组相比较,模型组细胞凋亡率为(50.8±1.5) %(P<0.01),不同浓度的花旗松素给药组可以降低细胞凋亡率,其中40 μmol·L^-1 花旗松素凋亡率为(41.5±2.7) %,与模型组比较呈显著性差异(P<0.05);凋亡酶caspase-3的活性与正常组(0.12±0.02) U·μg^-1比较,模型组的caspase-3的活性升高(2.37±0.16) U·μg^-1,P<0.01),与模型组相比,40 μmol·L^-1花旗松素组caspase-3显著降低(1.77±0.07) U·μg^-1, P<0.01).花旗松素能明显提高Aβ损伤神经元的细胞活力,抑制神经元的凋亡,降低凋亡酶caspase-3的活性. 结论: 花旗松素对Aβ损伤神经元具有保护作用,其机制可能与抑制caspase-3活性从而实现抗凋亡作用有关.

Abstract:

Objective: To investigate the neuroprotective effects and mechanism of taxifolin against Aβ induced neural damage. Method: Primary neurons were isolated and purified from cerebral cortex of suckling mouse. The neurons were co-cultured with Aβ and taxifolin for 24 h. CCK8 method was used to test cell viability. The apoptosis was examined by Hoechst 33258 nuclear staining, Annexin V-FITC/PI double staining and caspase-3 activity. Result: In cell viability, compared with the normal group, cell viability of model group decreased significantly (49.2±1.3) %, different concentrations of taxifolin could improve the neuronal activity, the cell viability of 80 μmol·L^-1 taxifolin increased to (68.7±3.2)%, compared with the model group. Compared with the normal group, the apoptosis rate of model group was (50.8±1.5)% (P<0.01), different concentrations of taxifolin could reduce the cell apoptosis rate, 40 μmol·L^-1 taxifolin apoptosis rate was (41.5±2.7)%,compared with the model group (P<0.05). Compared with the normal group, in model group, caspase-3 activity was (2.37±0.16) U·μg^-1(P<0.01), compared with the model group, 40 μmol·L^-1 taxifolin group decreased the caspase-3 activity (1.77±0.07) U·μg^-1(P<0.01). CCK8 assay displayed that taxifolin obviously increased cell viability. Hoechst 33258 nuclear staining and Annexin V-FITC/PI double staining showed that taxifolin could significantly decrease apoptotic rate compared with the Aβ treated group. Taxifolin also inhibited caspase-3 activity of neurons induced by Aβ. Conclusion: Taxifolin possesses the neuroprotective effects on Aβ damaged neurons, which may be associated with inhibition of caspase-3 activity in neurons to against apoptosis.