孕期酒精暴露诱发仔鼠海马神经元的自噬

Exposure to alcohol during pregnancy causing autophagy of hippocampal neurons of neonatal mice

目的:探讨孕期酒精暴露对仔鼠海马神经细胞自噬的影响。方法:建立孕期酒精暴露动物模型,采用透射电子显微镜、免疫荧光和Western Blot技术观察P0、P7和P14仔鼠海马CA1区锥体细胞自噬情况。结果:免疫荧光结果显示,同一时间点对照组仔鼠LC3阳性率明显少于酒精低剂量组和高剂量组,差异有统计学意义(P<0.05),且随着酒精剂量的增加自噬作用增强;同时,随着年龄的增加,各年龄组间LC3表达的阳性率下降(P<0.05)。电镜下酒精组锥体细胞内出现较多自噬体或自噬溶酶体结构,细胞器损伤严重。Western Blot检测各组间CA1区锥体细胞LC3蛋白的相对表达量与上述结果一致。结论:自噬参与了仔鼠海马CA1区锥体细胞的正常发育,在一定时期内随着生长发育,自噬作用逐渐减弱;孕期酒精暴露能导致仔鼠海马CA1区锥体细胞自噬增强,且有剂量依赖性和长时程效应。

Objective： To explore the effect of exposure to alcohol during pregnancy causing autophagy of hippocampal neurons of neonatal mice. Methods： The mouse models of gestational alcohol exposure were established, transmission electron microscope, immunofluoreseence, and Western Blot technique were used to observe autophagie conditions of pyramid cells in hippocampal CAI regions of neonatal mice on the day at birth, the seventh day and the fourteenth day after birth. Results： The results of immunofluorescence showed that the positive rates of LC3 protein of the neonatal mice in control group at the same time points were significantly lower than those in low dose alcohol group and high dose alcohol group （P 〈 0. 05） , the autophagy enhanced with the increase of alcohol dose. At the same time, the positive rates of LC3 protein in different age groups decreased with increasing age （P 〈 0. 05） . There was many autophagosome or autophagic lysosomes in pyramid cells of alcohol group under electron microscope, the injury of cell organelles was severe. Western Blot analysis showed that the relative expression levels of LC3 protein in pyramid cells in hippocampal CAI regions of different groups were in accordance with the above- mentioned results. Conclusion： Autophagy participates in the normal development of pyramid cells in hippocampal CAI regions of neonatal mice, which decreases gradually with the growth and development during a certain period; exposure to alcohol during pregnancy can cause the enhancement of autophagy of pyramid cells in hippocampal CAI regions of neonatal mice, showing a dose - dependent manner and long - term effect.