Early Neuroprotective Effects of Bovine Lactoferrin Associated with Hypothermia after Neonatal Brain Hypoxia-Ischemia in Rats.

Neonatal hypoxic-ischemic (HI) encephalopathy (HIE) in term newborns is a leading cause of mortality and chronic disability. Hypothermia (HT) is the only clinically available therapeutic intervention; however, its neuroprotective effects are limited. Lactoferrin (LF) is the major whey protein in milk presenting iron-binding, anti-inflammatory and anti-apoptotic properties and has been shown to protect very immature brains against HI damage. We hypothesized that combining early oral administration of LF with whole body hypothermia could enhance neuroprotection in a HIE rat model. Pregnant Wistar rats were fed an LF-supplemented diet (1 mg/kg) or a control diet from (P6). At P7, the male and female pups had the right common carotid artery occluded followed by hypoxia (8% O2 for 60') (HI). Immediately after hypoxia, hypothermia (target temperature of 32.5-33.5 °C) was performed (5 h duration) using Criticool®. The animals were divided according to diet, injury and thermal condition. At P8 (24 h after HI), the brain neurochemical profile was assessed using magnetic resonance spectroscopy (1H-MRS) and a hyperintense T2W signal was used to measure the brain lesions. The mRNA levels of the genes related to glutamatergic excitotoxicity, energy metabolism and inflammation were assessed in the right hippocampus. The cell markers and apoptosis expression were assessed using immunofluorescence in the right hippocampus. HI decreased the energy metabolites and increased lactate. The neuronal-astrocytic coupling impairments observed in the HI groups were reversed mainly by HT. LF had an important effect on astrocyte function, decreasing the levels of the genes related to glutamatergic excitotoxicity and restoring the mRNA levels of the genes related to metabolic support. When combined, LF and HT presented a synergistic effect and prevented lactate accumulation, decreased inflammation and reduced brain damage, pointing out the benefits of combining these therapies. Overall, we showed that through distinct mechanisms lactoferrin can enhance neuroprotection induced by HT following neonatal brain hypoxia-ischemia.

Early neurodevelopmental reflex impairments in a rodent model of cerebral palsy.

Cerebral palsy (CP) causes sensorimotor disabilities due to injury to the developing brain. Experimental models do not always induce the CP phenotype completely. Early neurological assessment predicts future impairments and is valuable during development. Using a rodent model characterized by brain injury caused by maternal inflammation and perinatal anoxia, and sensorimotor restriction (experimental cerebral palsy [ECP]), we describe early neurodevelopmental delays by assessing reflexes in a stage corresponding to the brain development of term infants (Postnatal Day [P] 8 in rats). Pregnant Wistar rats were injected with lipopolysaccharide (LPS; 200 µg/kg) (n = 6) or saline (n = 4) on Embryonic Days 18/19. Following delivery, 87 male and female pups were used. At P0, injured animals were exposed to anoxia for 20'. From P2 to P21, ECP rats were subjected to hindlimb movement restriction for 16 h/day. ECP group had impaired righting reflex and negative geotaxis and, interestingly, performed home bedding test better than controls. From P7, ECP animals showed decreased body weight compared with controls. Overall, data provide evidence showing that this CP model based on the association of brain damage followed by sensorimotor restriction mimics CP delays and highlights the valuable information given by early neurological assessment during the establishment of the CP phenotype.