Graf Michelle, Murgueitio Nicolas, Sheridan Margaret A, Quinn Robert A, Carlson Alexander L, Vogel Sarah C, Styner Martin A, Alex Ann M, Stephens Rebecca L, Roach Jeff, Sagarnaga Nicole, Mills-Koonce W Roger, Azcarate-Peril M Andrea, Short Sarah J, Knickmeyer Rebecca C, Propper Cathi B
School of Nursing, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; Virginia Commonwealth University, School of Nursing, Richmond, VA, USA.
Department of Psychology and Neuroscience, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
Physiol Behav. 2025 Oct 1;299:115001. doi: 10.1016/j.physbeh.2025.115001. Epub 2025 Jun 16.
The infant brain and gut microbiome both develop rapidly in early infancy. Growing evidence indicates that the gut microbiome plays a critical role in shaping neurodevelopment early in life, possibly through effects on brain regions involved in affective, interoceptive, and sensory processing. This study used magnetic resonance imaging (MRI) and whole genome sequencing of fecal samples to examine associations between the gut microbiome and brain structures in infants at 2 weeks of age. We identified significant relationships between specific gut microbiome characteristics and brain volumes in key regions involved in affective, sensory, and interoceptive processing. Our most consistent findings were associations between gut microbiome and insula volume, suggesting that the insula may be particularly sensitive to gut microbiome influences during the neonatal period. Specifically, a significant negative association between insula volume and the abundance of Veillonella was observed. Alpha diversity (Shannon) and functional pathways were also related to insula structure. Enterobacter was negatively associated with thalamus volume. These findings contribute to the growing evidence of a developing gut-brain axis, highlighting links between the gut and brain as early as 2 weeks of age. Future research should investigate the mechanisms by which specific microbial features impact neurodevelopment by way of the insula, as well as explore the potential long-term implications of these early relationships on sensory, interoceptive, and affective processing, and behavioral outcomes.
婴儿的大脑和肠道微生物群在婴儿早期均迅速发育。越来越多的证据表明，肠道微生物群在生命早期塑造神经发育过程中起着关键作用，可能是通过对参与情感、内感受和感觉处理的脑区产生影响。本研究使用磁共振成像（MRI）和粪便样本的全基因组测序，来检查2周龄婴儿肠道微生物群与脑结构之间的关联。我们确定了特定肠道微生物群特征与情感、感觉和内感受处理关键区域的脑容量之间存在显著关系。我们最一致的发现是肠道微生物群与脑岛体积之间的关联，这表明脑岛在新生儿期可能对肠道微生物群的影响特别敏感。具体而言，观察到脑岛体积与韦荣球菌丰度之间存在显著负相关。α多样性（香农指数）和功能途径也与脑岛结构有关。肠杆菌与丘脑体积呈负相关。这些发现为不断增加的发育中的肠-脑轴证据做出了贡献，突出了早在2周龄时肠道与大脑之间的联系。未来的研究应调查特定微生物特征通过脑岛影响神经发育的机制，以及探索这些早期关系对感觉、内感受和情感处理以及行为结果的潜在长期影响。
