No abstract

Maternal infection is associated with perinatal brain damage, but effects on the cerebellum are not known in detail. In this study, we examined the effects of placental inflammation induced by administering lipopolysaccharide into the uterine artery of pregnant sheep at 134–136 days gestation. The fetal brain was collected 72 h later and compared to brains collected from age-matched untreated fetuses. Placental lipopolysaccharide treatment had substantial effects on the fetal cerebellum, including increasing the number of cells undergoing apoptosis, widespread lipid peroxidation, and extravasation of plasma albumin, suggesting compromise of the cerebellar blood-brain barrier. These effects may account for some of the learning and motor deficits that emerge in neonates from pregnancies compromised by infection.

Birth asphyxia is associated with disturbed development of the neonatal brain. In this study, we determined if low-dose melatonin (0.1 mg/kg/day), administered to the mother over 7 days at the end of pregnancy, could protect against the effects of birth asphyxia in a precocial species – the spiny mouse (Acomys cahirinus). At 37 days of gestation (term is 38–39 days), pups were subjected to birth asphyxia (7.5 min uterine ischemia) and compared to Cesarean section-delivered controls. At 24 h of age, birth asphyxia had increased markers of CNS inflammation (microglia, macrophage infiltration) and apoptosis (activated caspase-3, fractin) in cortical gray matter, which were reduced to control levels by prior maternal melatonin treatment. Melatonin may be an effective prophylactic agent for use in late pregnancy to protect against hypoxic-ischemic brain injury at birth.

These data suggest that the HPA axes of females are more sensitive to the stimulatory effects of serotonin following acute treatment with the SSRI, sertraline.

The vulnerability of the fetal and newborn brain to events in utero or at birth that cause damage arising from perturbations of cerebral blood flow and metabolism, such as the accumulation of free radicals and excitatory transmitters to neurotoxic levels, has received considerable attention over the last few decades. Attention has usually been on the damage to cerebral structures, particularly, periventricular white matter. The rapid growth of the cerebellum in the latter half of fetal life in species with long gestations, such as the human and sheep, suggests that this may be a particularly important time for the development of cerebellar structure and function. In this short review, we summarize data from recent studies with fetal sheep showing that the developing cerebellum is particularly sensitive to infectious processes, chronic hypoxia and asphyxia. The data demonstrates that the cerebellum should be further studied in insults of this nature as it responds differently to the remainder of the brain. Damage to this region of the brain has implications not only for the development of motor control and posture, but also for higher cognitive processes and the subsequent development of complex behaviours, such as learning, memory and attention.