Maternal Oxytocin mitigates offspring autism-like behaviors and oxytocin system changes in a rat model.

Disruptions in early caregiver-infant interactions are increasingly linked to neurodevelopmental disorders like Autism Spectrum Disorder (ASD). Current interventions often focus on the child, overlooking the critical role of the maternal environment. Deficits in the oxytocinergic system are observed in both ASD and impaired mother-child interactions, suggesting a potential therapeutic target. This study explores whether enhancing maternal care via oxytocin can prevent the transmission of autism-like phenotypes from stressed mothers to their offspring, addressing a key gap in early intervention strategies.

Female rat pups underwent early-life maternal separation (MS) for 3 h/day from postnatal day (PND) 1-14. As adults, these females were mated and assigned to MS+Saline, MS+OXT (0.8 IU/kg intranasal, PND1-14), or control groups. Maternal behavior was meticulously assessed. Their male offspring were then evaluated during adolescence for social and repetitive behaviors, which are core autism-like phenotypes. Brains of the offspring were analyzed for hypothalamic OXT expression and hippocampal Oxytocin Receptors (OXTRs) expression using methods like qPCR or immunohistochemistry (implied by 'expression analysis').

Dams with a history of MS exhibited impaired maternal care, characterized by reduced nursing and increased harmful behaviors. Crucially, Oxytocin treatment significantly improved maternal care in these dams. The offspring of MS+Saline dams displayed core autism-like phenotypes, including social deficits and increased repetitive behaviors. These offspring also showed reduced OXT expression in the hypothalamus and reduced OXTR expression in the hippocampus. The most impactful finding was:

These behavioral and neurobiological abnormalities were ameliorated in the offspring of Oxytocin-treated MS dams. This demonstrates that maternal Oxytocin intervention can effectively prevent the development of these autism-like traits and associated neurobiological changes in the offspring, highlighting the profound influence of the maternal environment.