Cyclic O3 exposure synergizes with aging leading to memory impairment in male APOE ε3, but not APOE ε4, targeted replacement mice.

In this study, we tested the hypothesis that O3 exposure synergizes with the genetic risk factor APOE ε4 and aging leading to AD, using male apolipoprotein E (apoE)4 and apoE3 targeted replacement mice as men have increased risk exposure to high levels of O3 via working environments and few studies have addressed APOE ε4 effects on males. Surprisingly, our results show that O3 exposure impairs memory in old apoE3, but not old apoE4 or young apoE3 and apoE4, male mice. Further studies show that old apoE4 mice have increased hippocampal activities or expression of some enzymes involved in antioxidant defense, diminished protein oxidative modification, and neuroinflammation following O3 exposure compared with old apoE3 mice. These novel findings highlight the complexity of interactions between APOE genotype, age, and environmental exposure in AD development. PMID: 31207469 [PubMed - as supplied by publisher]
Source: Neurobiology of Aging - Category: Geriatrics Authors: Tags: Neurobiol Aging Source Type: research