Prenatal Maternal Stress Causes Sex-Specific Changes in Fetal Brain Development, Study Finds
A mouse study found that prenatal exposure to maternal stress during early pregnancy causes distinct sex-specific changes in the developing hypothalamus, a brain region critical for stress response and homeostasis. Male fetuses showed increased neuron numbers while female fetuses displayed enhanced dendritic branching, with female neural cells shifting toward a more male-like genetic expression pattern. The findings suggest that disrupted cell-to-cell communication in the developing brain may underlie previously observed sex differences in social behavior linked to prenatal stress.
Researchers exposed pregnant mice to cold stress between embryonic days 11.5 and 15.5 and analyzed how this affected neural stem and progenitor cells in the fetal hypothalamus of both male and female embryos. Using single-cell RNA sequencing, they discovered that maternal stress produced opposite effects in males and females: increasing neuron production in males while enhancing dendritic branching in females. Notably, the study found that maternal stress shifted female neural cells toward a more male-like transcriptional profile. The researchers identified specific molecular pathways affected by stress, particularly in females, including those involved in GABAergic neuron differentiation and neuronal projection growth. Cell-to-cell communication analysis revealed that maternal stress altered signaling patterns predominantly in female neural progenitor cells. These sex-specific developmental disruptions may explain previously documented differences in social behavior between male and female offspring exposed to prenatal stress.
What's missing
The study's own limitations are not detailed in the abstract provided. Additionally, the relevance and translatability of cold stress in mice to human prenatal stress exposure, and whether these specific molecular changes correlate with behavioral or clinical outcomes in humans, remain open questions.
What different sources said
- bioRxivCenter
Prenatal exposure to maternal stress drives sex-specific neurodevelopmental disruptions in the fetal hypothalamus
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