Neonatal Subarachnoid Hemorrhage Disrupts Multiple Aspects of Cerebellar Development

Area of Science:

• Neuroscience
• Neonatal Research
• Developmental Biology

Background:

• Survival rates for extremely low gestational age neonates (ELGANs) have improved, but neurodevelopmental dysfunction remains a concern.
• Cerebellar hemorrhagic injury (CHI) is increasingly recognized in ELGANs and linked to neurological deficits, yet underlying mechanisms are unclear.

Approach:

• Developed a novel mouse model of early isolated posterior fossa subarachnoid hemorrhage (SAH) in neonatal mice.
• Investigated acute (P8) and long-term (P42) effects of CHI on cerebellar development and cellular structure.
• Assessed motor function and learning using Rotarod and inverted screen assays, and evaluated the efficacy of Ketoprofen treatment.

Key Points:

• SAH induced decreased external granular layer proliferation, thinning, reduced Purkinje cell density, and increased Bergmann glial fiber crossings acutely.
• Long-term CHI effects included decreased Purkinje cell and molecular layer interneuron density, and increased Bergmann glial fiber crossings.
• Motor and learning assays showed no significant deficits, and Ketoprofen treatment did not provide neuroprotection.

Conclusions:

• CHI significantly disrupts cerebellar developmental programming in neonatal mice.
• Neuroinflammation may not be the primary target for neuroprotection against CHI in this model.
• Further research is needed to understand CHI mechanisms and develop effective therapeutic strategies for ELGANs.