The CRF‑CRFR1 Axis Mediates Prenatal Fear Stress‑Induced Hippocampal Mitochondrial Damage in Offspring via MAM...

Mitochondrial dysfunction has been recognized as one of the three hallmark biological features of autism spectrum disorder. This study is intended to investigate the molecular mechanisms underlying prenatal psychological fear stress‑induced hippocampal mitochondrial damage in offspring. Bioinformatics analysis revealed that the calcium signaling pathway, particularly the phospholipase C beta 1(PLCβ1)- inositol 1,4,5‑trisphosphate receptor (IP3R)- voltage‑dependent anion channel 1(VDAC1) pathway, may play a key role in prenatal stress‑induced hippocampal mitochondrial damage in offspring. To validate this, we examined pathway activation in the offspring hippocampus of prenatal fear stressed rats and in corticotropin-releasing hormone (CRH; also known as CRF in rodents) overexposed SH‑SY5Y cells, along with mitochondrial calcium levels in the cells. Prenatal fear stress induced depressive-like behavior and HPA axis activation in pregnant dams, and reduced survival and growth in offspring. Placental and neonatal brain CRF levels were elevated. At the early socialization stage (Postnatal day 21-30), model offspring showed normal basal but exaggerated stress-induced HPA responses. Their hippocampus exhibited expanded MAM coverage, reduced ER-mitochondria distance, and upregulated PLCβ1, IP3R1, VDAC1 expression, along with increased GRP75‑VDAC1 co‑localization, confirming MAM remodeling at the molecular level. In vitro, CRH (20 µM for 48 h or 5-20 µM for 96 h) inhibited SH-SY5Y cell proliferation, upregulated CRH receptor 1(CRHR1), PLCβ1, VDAC1, and increased mitochondrial calcium; these effects were reversed by the CRHR1 antagonist CP376395 or PLCβ1 knockdown. Furthermore, the MCU inhibitor DS16570511 partially reversed CRH‑induced mitochondrial calcium elevation and proliferation inhibition, suggesting that mitochondrial calcium overload contributes to the proliferation inhibition. Collectively, these results suggest that prenatal fear stress may, via the CRF-CRFR1 axis, influence the PLCβ1-IP3R-VDAC1 pathway, inducing MAM remodeling and mitochondrial calcium overload, thereby contributing to offspring hippocampal neuronal damage.