目的 探讨槲皮素对高糖培养海马神经元凋亡影响的可能作用机制。方法 新生24 h Sprague-Dawley大鼠,取海马神经元原代培养,分为正常对照组、高糖组、槲皮素组、槲皮素+Akt抑制剂组和Akt激动剂组。各组在不同条件培养基中培养72 h后流式细胞仪检测细胞凋亡率,Western blotting检测各组神经元p-Akt、Akt、Bcl-2和Bax蛋白表达。结果 与正常对照组相比,高糖组细胞凋亡率明显升高(P<0.01),p-Akt/Akt和Bcl-2/Bax均明显减少(P<0.01);与高糖组比较,槲皮素组、Akt激动剂组细胞凋亡率明显下降(P<0.01),p-Akt/Akt和Bcl-2/Bax均明显升高(P<0.01)。与槲皮素+Akt抑制剂组比较,槲皮素组细胞凋亡率明显下降(P<0.01),p-Akt/Akt和Bcl-2/Bax均明显升高(P<0.01)。结论 槲皮素能够减少高糖培养下海马神经元的凋亡,其作用机制与增加Akt信号通路中Akt蛋白磷酸化的程度,进而增加Bcl-2蛋白的表达、抑制Bax蛋白的表达有关。
Objective To explore the possible mechanism of quercetin on apoptosis of hippocampal neurons cultured in high glucose. Methods Hippocampus was obtained from newborn 24 hours Sprague-Dawley rats and then primarily cultured. Then hippocampal neurons were divided into normal control group, high glucose group, quercetin group, quercetin+Akt inhibitor group and Akt agonist group. After each group was cultured in different conditioned medium for 72 hours, they were detected the apoptosis of neurons with flow cytometry, and the expression of Akt, p-Akt, Bcl-2 and Bax with Western blotting. Results Compared with the normal control group, the apoptosis rate of hippocampal neurons increased significantly (P<0.01), and p-Akt/Akt and Bcl-2/Bax decreased significantly (P<0.01) in the high glucose group. Compared with the high glucose group, the apoptosis rates of hippocampal neurons decreased significantly (P<0.01), and p-Akt/Akt and Bcl-2/Bax increased significantly (P<0.01) in the quercetin group and the Akt agonist group. Compared with the quercetin+Akt inhibitor group, the apoptosis rate of hippocampal neurons decreased significantly (P<0.01), and p-Akt/Akt and Bcl-2/Bax increased significantly (P<0.01) in the quercetin group. Conclusion Quercetin could reduce the apoptosis of hippocampal neurons cultured in high glucose, which may be achieved by increasing the phosphorylation of Akt protein in Akt signal pathway, and then increasing the expression of Bcl-2 and inhibiting the expression of Bax.
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