Laboratory of Biochemistry, Department of Biological Applications and Technology, University of Ioannina, Ioannina, Greece.
Biomedical Research Institute, Foundation for Research and Technology-Hellas (FORTH), Ioannina, Greece.
Mol Neurobiol. 2024 Dec;61(12):10593-10612. doi: 10.1007/s12035-024-04116-5. Epub 2024 May 18.
Early handling (EH), the brief separation of pups from their mother during early life, has been shown to exert beneficial effects. However, the impact of EH in a high anxiety background as well as the role of brain mitochondria in shaping EH-driven responses remain elusive.Here, we used a high (HAB) vs. normal (NAB) anxiety-related behavior mouse model to study how EH affects pup and dam behavior in divergent anxiety backgrounds. We also investigated EH-induced effects at the protein and mRNA levels in adult male HAB mice in the hypothalamus, the prefrontal cortex, and the hippocampus by examining the same mitochondrial/energy pathways and mitochondrial dynamics mechanisms (fission, fusion, biogenesis, and mitophagy) in all three brain regions.EH exerts anxiolytic effects in adult HAB but not NAB male mice and does not affect HAB or NAB maternal behavior, although basal HAB vs. NAB maternal behaviors differ. In adult HAB male mice, EH does not impact oxidative phosphorylation (OXPHOS) and oxidative stress in any of the brain regions studied but leads to increased protein expression of glycolysis enzymes and a correlation of anxiety-related behavior with Krebs cycle enzymes in HAB mice in the hypothalamus. Intriguingly, EH alters mitochondrial dynamics by increasing hypothalamic DRP1, OPA1, and PGC1a protein levels. At the mRNA level, we observe altered, EH-driven mitochondrial dynamics mRNA signatures which predominantly affect the prefrontal cortex.Taken together, our results show that EH exerts anxiolytic effects in adulthood in high anxiety and modulates mitochondrial dynamics pathways in a brain region-specific manner.
早期处理(EH),即在生命早期将幼崽与母亲短暂分离,已被证明具有有益的效果。然而,EH 在高焦虑背景下的影响以及大脑线粒体在塑造 EH 驱动反应中的作用仍然难以捉摸。在这里,我们使用了一种高(HAB)与正常(NAB)焦虑相关行为的小鼠模型,研究 EH 如何在不同焦虑背景下影响幼崽和母鼠的行为。我们还通过检查下丘脑、前额叶皮层和海马体中相同的线粒体/能量途径和线粒体动力学机制(分裂、融合、生物发生和自噬),研究了 EH 在成年 HAB 雄性小鼠中的蛋白和 mRNA 水平上的诱导效应。EH 在成年 HAB 雄性小鼠中具有抗焦虑作用,但在 NAB 雄性小鼠中没有作用,也不影响 HAB 或 NAB 母性行为,尽管 HAB 与 NAB 母性行为存在差异。在成年 HAB 雄性小鼠中,EH 不会影响任何研究脑区的氧化磷酸化(OXPHOS)和氧化应激,但会导致糖酵解酶的蛋白表达增加,并且 HAB 小鼠的下丘脑与焦虑相关行为与克雷布斯循环酶相关。有趣的是,EH 通过增加下丘脑 DRP1、OPA1 和 PGC1a 蛋白水平来改变线粒体动力学。在 mRNA 水平上,我们观察到改变的、EH 驱动的线粒体动力学 mRNA 特征,主要影响前额叶皮层。总之,我们的研究结果表明,EH 在成年期在高焦虑背景下发挥抗焦虑作用,并以特定于脑区的方式调节线粒体动力学途径。