Prenatal Maternal Stress Causes Sex-Specific Changes in Fetal Brain Development, Study Finds
A new mouse study found that prenatal exposure to maternal cold stress disrupts hypothalamic neural stem cell development differently in male and female fetuses. Males showed increased neuron numbers while females exhibited enhanced dendritic branching and a shift toward male-like gene expression patterns. The findings may help explain known sex differences in neurodevelopmental disorders linked to prenatal stress.
Researchers used a mouse model of prenatal cold stress exposure — applied from embryonic day 11.5 to 15.5 — to examine how maternal stress shapes neural stem and progenitor cell (NSPC) development in the fetal hypothalamus. Single-cell RNA sequencing revealed that male and female NSPCs have distinct baseline transcriptional profiles even without stress, and that maternal stress pushes female NSPCs toward a more male-like gene expression state. In males, stress increased the number of TUJ1+ neurons, while in females it enhanced neuronal dendritic arborization and upregulated pathways related to GABAergic differentiation and neuronal projection morphogenesis. These stress-induced transcriptional changes in females persisted into more differentiated neuronal populations, suggesting lasting developmental consequences. Ligand-receptor interaction analysis further showed that maternal stress predominantly disrupts cell-cell communication within female NSPCs. The authors propose that these disrupted intercellular signaling patterns may underlie previously reported sex differences in social behaviors in this model, connecting molecular findings to behavioral outcomes.
What's missing
As a preprint on bioRxiv, this study has not yet undergone peer review. Key limitations include reliance on a single, non-naturalistic stressor (cold exposure) whose translatability to human prenatal stress is uncertain, restriction to a narrow embryonic window (E11.5–E15.5), and the absence of postnatal behavioral or physiological follow-up within this study itself. Whether the observed transcriptional shifts are reversible or causally linked to behavioral outcomes remains an open question.
What different sources said
- bioRxivCenter
Prenatal exposure to maternal stress drives sex-specific neurodevelopmental disruptions in the fetal hypothalamus
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