目的: 探究结节性硬化症蛋白1(Tuberous Sclerosis Complex 1, TSC1)在低氧预适应(hypoxic preconditioning, HPC)条件下是否通过哺乳动物雷帕霉素靶蛋白(Mammalian Target of Rapamycin, mTOR)调控自噬,从而减轻神经元损伤。方法: 应用HT22细胞建立Hypoxia与HPC模型,采用流式细胞术检测细胞凋亡水平;对HT22细胞进行TSC1基因干预(敲除/过表达),随后应用Western blot检测细胞mTOR蛋白与LC3自噬蛋白水平。结果: 流式细胞术检测结果:HPC组与Hypoxia组相比,HPC组能够显著降低HT22细胞的神经元凋亡,具有统计学意义(P＜0.05)。Western blot检测结果:过表达TSC1并进行Hypoxia处理,mTOR表达降低,同时LC3Ⅱ/LC3I蛋白水平降低,具有统计学意义(P＜0.05)。敲除TSC1并进行HPC处理,增加mTOR蛋白表达,同时LC3Ⅱ/LC3I蛋白水平升高,具有统计学意义(P＜0.05)。结论: TSC1在HPC条件下可能通过调控mTOR通路介导自噬发挥神经保护作用。
Objective: Investigating whether tuberous sclerosis complex 1 (TSC1) modulates autophagy via the mammalian target of rapamycin (mTOR) pathway under hypoxic preconditioning (HPC) conditions to alleviate neuronal injury. Methods: Hypoxia and HPC models were established using HT22 hippocampal neuronal cells. Apoptosis was quantified by flow cytometry. Genetic interventions (knockout/overexpression) targeting TSC1 were performed, followed by Western blot analysis of mTOR and LC3 autophagy marker (LC3Ⅱ/LC3I ratio) expression. Results: Compared to the hypoxia group, HPC significantly reduced neuronal apoptosis in HT22 cells (P＜0.05). TSC1 overexpression during hypoxia suppressed mTOR expression and concurrently decreased LC3Ⅱ/LC3I levels (P＜0.05). Conversely, TSC1 knockout under HPC elevated mTOR protein levels and increased the LC3Ⅱ/LC3I ratio (P＜0.05). Conclusion: TSC1 exerts neuroprotective effects under HPC likely through mTOR pathway-dependent regulation of autophagy.
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