Developmental Disturbances in Animal Models of Autism Spectrum Disorder.

This review looked at how autism signs appear in young animals (first 3 weeks of life) used in research. Scientists found early signs like delayed eye opening, changes in reflexes, sensory problems, and reduced baby animal calls. The study identified important brain areas and chemical systems that might be involved in autism. The researchers noted that oxytocin shows promise but translating animal research to humans is challenging.

This review examines early autism spectrum disorder (ASD) symptoms in animal models during the first three weeks of life. The study synthesizes findings from transgenic and neurotoxic rodent models, identifying early developmental markers including delayed eye opening, altered motor reflexes, sensory dysfunction, and reduced ultrasonic vocalization. Key brain regions implicated include the subventricular zone, cortex, hippocampus, and cerebellum. The review highlights disruptions in neurotransmitter systems, particularly GABA-glutamate imbalance, developmental GABA shifts, and alterations in serotonin, dopamine, and oxytocin systems.

The authors emphasize the translational challenges in ASD research, particularly regarding oxytocin as a therapeutic target, and recommend using diverse animal models with comprehensive behavioral monitoring to better reflect ASD complexity.

The review suggests monitoring multiple behavioral indicators simultaneously in research and clinical settings. The identification of early developmental markers and affected brain systems may inform early intervention strategies, though translational challenges from animal models to human applications remain significant.

This is a review of animal models which have inherent translational challenges to humans. The study emphasizes significant ambiguity and heterogeneity in symptoms. Sample sizes and methodological details of reviewed studies are not reported.

Although the early signs of autism spectrum disorder (ASD) are widely studied, the significant ambiguity and heterogeneity in symptoms require the comparison of available models, approaches, and the search for common denominators and key indicators. Early ASD symptoms in animal models include impaired somatic development (e.g., delayed eye opening), alterations in primitive motor reflexes, disrupted sensory function as well as communication deficits, such as reduced ultrasonic vocalization. This review aims to summarize early ASD-related symptoms based on studies involving transgenic or neurotoxic rodent models (postnatal days 1-21) and to compare these with human resemblance. The key brain areas (subventricular zone, cortex, hippocampus, cerebellum, etc.) as well as relevant neurotransmitter systems (GABA-glutamate imbalance, developmental GABA shift, serotonin, dopamine, oxytocin [OT], etc.) were identified as potential targets for intervention.

OT, although a promising candidate, exemplifies the translational challenges inherent in ASD research. Therefore, it is recommended to monitor a wide range of behavioral signs simultaneously and employ diverse models (e.g., genetic, developmental, environmental, or combination) in preclinical studies to more accurately reflect the complexity of the disorder.