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bioRxiv · 10.1101/2025.09.20.677502

PEDF peptides rescue defects in neurite morphogenesis and intracellular calcium response in cortical neurons from mice exposed to valproic acid

Liu, X.·Toyooka, K.
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Abstract

Pigment epithelial-derived factor (PEDF) is a multifunctional protein produced predominantly by the retinal pigment epithelium and expressed in many tissues, including the brain, highlighting its participation in crucial processes, such as neuroprotection and angiogenesis. Some neurodevelopmental disorders, such as ASD, are characterized by neurodevelopmental abnormalities, including altered neurite formation, spine formation, and neuronal activities. Many efforts have been made to resolve NDDs, but until now, some symptoms remain untargeted. PEDF is involved in many steps of neurodevelopment. The treatment of PEDF peptide might improve the outcome of NDD symptoms by altering neuronal morphologies. We used PEDF peptides that contain different functional domains to study the effect of administering PEDF peptides on neuronal morphology in a prenatal valproic acid (VPA)-exposed mouse model. We identified that treatment with PEDF peptides rectified the abnormalities in neurite formation and spine formation in VPA-exposed cortical neurons. In vitro calcium imaging showed abnormalities in spontaneous activity in VPA-exposed cortical neurons. Treatment of a short PEDF peptide normalized the intracellular calcium response to the control level. Accordingly, PEDF peptides have the prospect of serving as potential treatments for patients with neurodevelopmental disorders, such as ASD.

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Liu, X., Toyooka, K.. 2025-09-21. PEDF peptides rescue defects in neurite morphogenesis and intracellular calcium response in cortical neurons from mice exposed to valproic acid. https://doi.org/10.1101/2025.09.20.677502

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