蛇床子素通过激活 PI3K/Akt 通路减轻谷氨酸诱导的海马神经元损伤

目的：研究蛇床子素(osthole，OST)减轻谷氨酸诱导的HT22细胞损伤的机制。方法：建立谷氨酸诱导的 HT22细胞损伤模型；HT22损伤细胞经OST处理，MTS法检测细胞活力；乳酸脱氢酶(lactate dehydrogenase，LDH)释放 实验检测HT22细胞LDH漏出率；caspase-3活性检测试剂盒测定各组caspase-3活性；Western印迹法测定细胞内磷脂酰肌 醇(-3)激酶(phosphatidylinositol-3-kinase，PI3K)，蛋白激酶B(protein kinase B，Akt)，磷酸化PI3K(p-PI3K)和磷酸化Akt(p- Akt)蛋白表达情况。结果：OST在0~10 mmol/L范围内呈剂量依赖性提高谷氨酸诱导的HT22细胞活力，降低LDH漏出 率，改善HT22细胞损伤。此外，OST显著上调谷氨酸损伤细胞p-PI3K和p-Akt蛋白表达，而PI3K抑制剂LY294002明显 抑制OST谷氨酸损伤细胞p-Akt蛋白表达的上调作用。结论：OST对谷氨酸损伤的HT22细胞具有保护作用，其保护作 用机制可能是通过激活PI3K/Akt信号通路来实现的。

Osthole ameliorates glutamate-induced toxicity in HT22 cells via activating PI3K/Akt signaling pathway

Objective: To investigate the neuroprotective effects of osthole (OST) on glutamate-induced toxicity in hippocampal HT22 cells and to explore the correlation between the protection and phosphatidylinositol-3-kinase/protein kinase B (PI3K/Akt) signaling pathway. Methods: The cell injury model of HT22 was induced by glutamate and the cell viability was detected by MTS assay. Th e lactate dehydrogenase (LDH) release and the caspase-3 activity were determined by commercial kits. Western blot analysis was utilized to detect the protein levels ofPI3K, Akt, p-PI3K and p-Akt. Results: OST markedly improved the cell survival and decreased the LDH release in glutamatetreated HT22 cells in a dose-dependent manner. Furthermore, the levels of p-PI3K and p-Akt proteins were significantly increased in glutamate and OST-co-treated HT22 cells. The effect of OST on p-Akt phosphorylation in HT22 cells was attenuated in the presence of PI3K specific inhibitor (LY294002). Conclusion: OST protects HT22 cells from glutamate excitotoxicity through a mechanism involving the activation of PI3K/Akt signaling pathway.