Multicomponent Training Prevents Memory Deficit Related to Amyloid-ß Protein-Induced Neurotoxicity.

BACKGROUND: Alzheimer's disease (AD) is characterized by the accumulation of the amyloid-ß peptide in the brain, leading to early oxidative stress and neurotoxicity. It has been suggested that physical exercise could be beneficial in preventing AD, but studies with multicomponent training are scanty. OBJECTIVE: Verify the effects of multicomponent exercise training to prevent deficits in recognition memory related to Aß neurotoxicity. METHODS: We subjected Wistar rats to multicomponent training (including aerobic and anaerobic physical exercise and cognitive exercise) and then infused amyloid-ß peptide into their hippocampus. RESULTS: We show that long-term multicomponent training prevents the amyloid-ß-associated neurotoxicity in the hippocampus. It reduces hippocampal lipid peroxidation, restores antioxidant capacity, and increases glutathione levels, finally preventing recognition memory deficits. CONCLUSION: Multicomponent training avoids memory deficits related to amyloid-ß neurotoxicity on an animal model.

Oxidative stress in asphyxiated term infants resuscitated with 100% oxygen.

OBJECTIVE: To test the hypothesis that resuscitation of asphyxiated infants with pure oxygen causes hyperoxemia and oxidative stress.Study design Asphyxiated term newborn infants (n = 106) were randomly resuscitated with room air (RAR = 51) or 100% oxygen (OxR = 55). The Apgar score, time of the first cry, and establishment of a sustained pattern of respiration were recorded. Assays performed included: blood gases; reduced glutathione (GSH) and oxidized glutathione (GSSG) in whole blood; glutathione-related enzyme activities; and superoxide dismutase activity (SOD) in erythrocytes. RESULTS: The RAR group needed less time of ventilation for resuscitation (5.3 +/- 1.5 vs 6.8 +/- 1.2 min; P <.05). Pure oxygen caused hyperoxemia (PO(2), 126.3 +/- 21.8 mm Hg) that did not occur with the use of room air (PO(2), 72.2 +/- 6.8 mm Hg). GSH was decreased and GSSG, the glutathione cycle enzymes, and SOD activities were increased in both asphyxiated groups. However, the 100% oxygen-resuscitated group showed significantly greater alterations that correlated positively with hyperoxemia. CONCLUSIONS: Asphyxia causes oxidative stress in the perinatal period, and resuscitation with 100% oxygen causes hyperoxemia and increased oxidative stress. Because there are no advantages to resuscitation with 100% oxygen, room air may be preferred under certain circumstances for the resuscitation of asphyxiated neonates.