【摘要】 目的:观察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。更多还原

【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.更多还原