Astrocyte responses after neonatal ischemia: the yin and the yang

Neonatal encephalopathy is a major predictor of neurodevelopmental disability in term infants and occurs in 1 to 6 of every 1,000 live term births. Despite improvements in perinatal practice during the past several decades, the incidence of cerebral palsy attributed to neonatal asphyxia remained essentially unchanged, primarily because management strategies were supportive and not targeted toward the processes of ongoing injury. Traditionally, experimental research in vivo focused on neurons, and more recently, oligodendrocytes whereas astrocytes have been more or less neglected. This review aims at dissecting possible protective as well as destructive roles of astrocytes in the immature ischemic brain to stimulate further research into this unexplored aspect of brain pathophysiology.