Rapamycin Cannot Reduce Seizure Susceptibility in Infantile Rats with Malformations of Cortical Development Lacking mTORC1 Activation

Specific inhibitor of Wnt/beta-catenin pathway can alter behavioral responses in young rats with malformed cortices

The Wnt/beta-catenin pathway plays a crucial role in regulating cellular processes and has been implicated in neural activity-dependent learning as well as anxiety. However, the role of this pathway in young children with abnormal cortical development is unknown. Cortical malformations at early development, behavioral abnormalities, and a susceptibility to seizures have been reported in rats prenatally exposed to methylazoxymethanol. In this study, we aimed to investigate whether we could improve the behavioral deficits in young rats with malformed cerebral cortices by modulation of the Wnt/beta-catenin pathway. We found a small molecule Wnt/beta-catenin inhibitor (CWP) that increased exploratory behavior in the open field test (P9, CWP 100 ug treatment, peripheral exploration, P = 0.011) and social behavior test (P12, CWP 250 ug treatment, distance traveled in center, P = 0.033) and decreased anxiety in fear conditioning. However, it did not reduce the susceptibility to seizures. After high dose (250 ug) CWP treatment at P12, phosphocreatine and glutathione (GSH) were decreased in the cortex at P15 (P = 0.021). These findings suggest that the role of Wnt/beta-catenin signaling in exploratory behavior and anxiety during early development warrants further investigation.