Autophagy activated by tuberin/mTOR/p70S6K suppression is a protective mechanism against local anaesthetics neurotoxicity.
Autophagy activated by tuberin/mTOR/p70S6K suppression is a protective mechanism against local anaesthetics neurotoxicity.
复制标题
马铃薯蛋白/mTOR/p70S6K抑制激活的自噬是针对局麻药神经毒性的保护机制。
DOI：
10.1111/jcmm.13003
复制
发表时间：
2017-03
影响因子：
5.3
通讯作者：
Ding Z
中科院分区：
文献类型：
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作者：
Xiong J;Kong Q;Dai L;Ma H;Cao X;Liu L;Ding Z
局麻药广泛应用于周围神经阻滞、硬膜外麻醉、脊麻和疼痛管理。然而，长时间或高剂量暴露于LA可引起潜在的神经元损伤。自噬是细胞内蛋白质和细胞器的大量降解过程。然而，LAs对神经细胞自噬的影响以及自噬对LAs神经毒性的影响尚不清楚。为了回答这些问题，将脂质LA（普鲁卡因和丁卡因）和酰胺LA（布比卡因、利多卡因和罗哌卡因）施用至人神经母细胞瘤SH-SY 5 Y细胞。以MTT比色法、形态学改变和半数致死量评价神经毒性。通过自体溶酶体形成（双重荧光LC 3测定）、LC 3-II生成和p62蛋白降解（免疫印迹）估计自噬通量。通过免疫印迹分析检查信号传导改变。通过用beclin-1 siRNA转染实现自噬的抑制。我们观察到LA以剂量依赖性方式降低细胞活力。LA的神经毒性依次为丁卡因>布比卡因>罗哌卡因>普鲁卡因>利多卡因。LA增加了自噬通量，这反映在自溶酶体形成和LC 3-II生成的增加以及p62水平的降低。此外，LA抑制了结核菌素/mTOR/p70 S6 K信号传导，这是自噬激活的负调节因子。最重要的是，beclin-1敲低导致的自噬抑制加剧了LA引起的细胞损伤。我们的数据表明，自噬通量通过抑制tuberin/mTOR/p70 S6 K信号传导被LA上调，自噬激活作为对LA神经毒性的保护机制。因此，自噬操作可能是预防LA诱导的神经元损伤的替代治疗干预。
The local anaesthetics (LAs) are widely used for peripheral nerve blocks, epidural anaesthesia, spinal anaesthesia and pain management. However, exposure to LAs for long duration or at high dosage can provoke potential neuronal damages. Autophagy is an intracellular bulk degradation process for proteins and organelles. However, both the effects of LAs on autophagy in neuronal cells and the effects of autophagy on LAs neurotoxicity are not clear. To answer these questions, both lipid LAs (procaine and tetracaine) and amide LAs (bupivacaine, lidocaine and ropivacaine) were administrated to human neuroblastoma SH‐SY5Y cells. Neurotoxicity was evaluated by MTT assay, morphological alterations and median death dosage. Autophagic flux was estimated by autolysosome formation (dual fluorescence LC3 assay), LC3‐II generation and p62 protein degradation (immunoblotting). Signalling alterations were examined by immunoblotting analysis. Inhibition of autophagy was achieved by transfection with beclin‐1 siRNA. We observed that LAs decreased cell viability in a dose‐dependent manner. The neurotoxicity of LAs was tetracaine > bupivacaine > ropivacaine > procaine > lidocaine. LAs increased autophagic flux, as reflected by increases in autolysosome formation and LC3‐II generation, and decrease in p62 levels. Moreover, LAs inhibited tuberin/mTOR/p70S6K signalling, a negative regulator of autophagy activation. Most importantly, autophagy inhibition by beclin‐1 knockdown exacerbated the LAs‐provoked cell damage. Our data suggest that autophagic flux was up‐regulated by LAs through inhibition of tuberin/mTOR/p70S6K signalling, and autophagy activation served as a protective mechanism against LAs neurotoxicity. Therefore, autophagy manipulation could be an alternative therapeutic intervention to prevent LAs‐induced neuronal damage.