alpha-Phenyl-n-tert-butyl-nitrone attenuates lipopolysaccharide-induced brain injury and improves neurological reflexes and early sensorimotor behavioral performance in juvenile rats.

Our previous study showed that treatment with alpha-phenyl-n-tert-butyl-nitrone (PBN) after exposure to lipopolysaccharide (LPS) reduced LPS-induced white matter injury in the neonatal rat brain. The object of the current study was to further examine whether PBN has long-lasting protective effects and ameliorates LPS-induced neurological dysfunction. Intracerebral (i.c.) injection of LPS (1 mg/kg) was performed in postnatal day (P) 5 Sprague Dawley rat pups and PBN (100 mg/kg) or saline was administered intraperitoneally 5 min after LPS injection. The control rats were injected (i.c.) with sterile saline. Neurobehavioral tests were carried out from P3 to P21, and brain injury was examined after these tests. LPS exposure resulted in severe brain damage, including enlargement of ventricles bilaterally, loss of mature oligodendrocytes, impaired myelination as indicated by the decrease in myelin basic protein immunostaining, and alterations in dendritic processes in the cortical gray matter of the parietal cortex. Electron microscopic examination showed that LPS exposure caused impaired myelination as indicated by the disintegrated myelin sheaths in the juvenile rat brain. LPS administration also significantly affected neurobehavioral functions such as performance in righting reflex, wire hanging maneuver, cliff avoidance, negative geotaxis, vibrissa-elicited forelimb-placing test, beam walking, and gait test. Treatment with PBN, a free radical scavenger and antioxidant, provided protection against LPS-induced brain injury and associated neurological dysfunction in juvenile rats, suggesting that antioxidation might be an effective approach for therapeutic treatment of neonatal brain injury induced by infection/inflammation.

Movement disorders in the tropics.

The spectrum of movement disorders in the tropics is different from that seen in the industrialized nations of the west. This is not surprising given the unique combination of environmental and population characteristics in the tropics. Infections seldom encountered in the west such as tuberculous meningitis, typhoid fever, Japanese encephalitis, malaria, trypanosomiasis or cysticercosis are often seen in the tropics and with global patterns of travel and immigration these conditions are becoming more common worldwide. Movement disorders associated with these infections, HIV, slow virus and prion disease are discussed. Taking into account the diverse etiologies of movement disorders in the tropics, movement disorders with a nutritional basis such as the infantile tremor syndrome, seasonal ataxia and tropical ataxic neuropathy, and manganese neurotoxicity are also reviewed. Finally, certain special characteristics of ubiquitous disorders such as Parkinson's disease, and disorders with a genetic basis such as Wilson's disease and spinocerebellar degeneration are described.