戴国英 刘慧慧 马丹 于化新 单德红

【摘要】 目的：觀察50%限食（dietary restriction，DR）14 d对大鼠海马神经元线粒体的结构和功能及其自噬的影响，探讨DR的安全性。方法：选取16只雄性SD大鼠按体质量配对分为正常组和DR组，每组8只。正常组给予自由进食，DR组给予50%DR，14 d后取海马组织，透射电镜观察海马神经元线粒体超微结构，JC-1法检测线粒体膜电位（ΔΨm），ELISA法检测线粒体ATP和反应性氧簇（reactive oxygen species，ROS）水平，Western blot法检测微管相关蛋白轻链3（light chain 3，LC3）-Ⅰ和Ⅱ表达并计算两者比值。结果：两组线粒体均边缘清楚，但正常组相对较大，嵴呈片状，数量较多，而DR组的线粒体较小，且存在嵴减少现象;与正常组比较，ΔΨm和ATP水平均下降（P<0.05），但ROS水平变化不明显（P>0.05），LC3-Ⅱ表达上升，LC3-Ⅰ表达下降，LC3-Ⅱ/Ⅰ比值升高。结论：海马神经元线粒体可被14 d的50%DR负性影响，但可通过增强线粒体自噬进行对抗。

【关键词】 饮食限制 海马 神经元 线粒体自噬 微管相关蛋白轻链3

Effect of Diet Restriction on Mitophagy in Hippocampal Neuron of Rats/DAI Gouying， LIU Huihui， MA Dan， YU Huaxin， SHAN Dehong. //Medical Innovation of China， 2021， 18（13）： 0-031

[Abstract] Objective： To observe the effects of 50% dietary restriction （DR） on the structure and function of hippocampal neuron mitochondria and mitophagy of rats for 14 d， and to explore the safety of DR. Method： A total of 16 male SD rats were selected and divided into normal group and DR group according to body weight， with 8 rats in each group. The normal group was given free food， and the DR group was given 50%DR. After 14 days， the hippocampal tissue was taken， and the mitochondrial ultrastructure of the hippocampal neurons was observed by transmission electron microscopy. The mitochondrial membrane potential （ΔΨm） was detected by JC-1 method. Mitochondrial ATP and reactive oxygen species （ROS） levels were detected by ELISA， and microtubule-associated protein light chain 3 （LC3）-Ⅰ and Ⅱ expression were detected by Western blot， and their ratio was calculated. Result： Mitochondria in both groups had clear margins， but the normal group was relatively large with flaky cristae and more number， while the DR group had smaller mitochondria with reduced cristae; compared with the normal group， the levels of ΔΨM and ATP were decreased （P<0.05）， but the ROS level was not significantly changed （P>0.05）， the expression of LC3-Ⅱ was increased， the expression of LC3-Ⅰ was decreased， and the ratio of LC3-Ⅱ/Ⅰ was increased. Conclusion： Hippocampal neuronal mitochondria might be negatively affect by 14 d 50%DR， but it can be opposited by increasing mitophagy.

[Key words] Dietary restriction Hippocampus Neuron Mitophagy Microtubule-associated protein light chain 3

First-authors address： College of Integrated Traditional Chinese Medicine and Western Medicine， Liaoning University of Traditional Chinese Medicine， Shenyang 110847， China

doi：10.3969/j.issn.1674-4985.2021.13.007

研究显示，多食已成为众多疾病的新的病因，而饮食限制（dietary restriction，DR）也成为新的治疗手段[1-2]。DR对神经系统退行性病变、糖尿病、心血管疾病和癌症等治疗具有一定作用，其机制与保护线粒体和抗氧化等有关[3-5]。DR的本质是暂时减少细胞的营养供给，而线粒体对营养信号极为敏感，其结构、功能和胞内分布会随之发生变化，称为线粒体可塑性[6]。线粒体是多功能网状细胞器，其损伤不仅减少细胞供能，还会干扰胞内钙稳态和生物合成，甚至诱发氧化应激和免疫异常，从而参与众多疾病的发生发展[7-8]。因此，如何在开展DR的同时，尽量减少其对线粒体的影响至关重要。……