CD36 upregulation mediated by intranasal LV-NRF2 treatment mitigates hypoxia-induced progression of Alzheimer's-like pathogenesis.
OBJECTIVE
There is extensive evidence that oxidative stress induces cellular dysfunction in the brain and plays a critical role in Alzheimer's disease (AD) pathogenesis. Hypoxia increases factors involved in oxidative stress injury and contributes to the onset and progression of AD. Nuclear factor erythroid 2-related factor 2 (NRF2), a major component regulating antioxidant response, is attenuated in the AD brain. Importantly, NRF2 directly regulates the alternative first exons of CD36, an important participant in oxidative and inflammatory processes. To explore the effects of hypoxia-induced deterioration of AD-like pathogenesis and investigate the correlation between hypoxia-induced NRF2 signal alterations and CD36 expression, we examined the NRF2 signaling, CD36, and oxidative stress events in hypoxia-treated APPswe/PSEN1dE9 (APP/PS1) mice brain.


RESULTS
We observed that hypoxia treatment increased oxidative stress, exacerbated inflammation, and aggravated learning defects in aged APP/PS1 mice. Microglia from hypoxia-treated mice brain exhibited marked reduction in CD36 expression and inhibition of β-amyloid (Aβ) degradation. Accordingly, hypoxia treatment caused a decrease in transactivation of NRF2 target genes in the aging mouse brain. Intranasal administration with a lentiviral vector encoding human NRF2 increased CD36 expression, ameliorated the weak antioxidant response triggered by hypoxia, diminished Aβ deposition, and improved spatial memory defects.


METHODS
In this study, we demonstrated for the first time that NRF2 intranasal treatment-induced increases of CD36 could enhance Aβ clearance in AD transgenic mouse.


CONCLUSIONS
These results suggest that targeting NRF2-mediated CD36 expression might provide a beneficial intervention for cognitive impairment and oxidative stress in AD progression.
1 Key Laboratory of Medical Cell Biology of Ministry of Education of China, Department of Pathophysiology, China Medical University , Shenyang, China .
Chun-Yan
CY
Wang
Zhan-You
ZY
Wang
Jing-Wei
JW
Xie
Jian-Hui
JH
Cai
Tao
T
Wang
Ye
Y
Xu
Xu
X
Wang
Li
L
An
D000544:Alzheimer Disease / Q000235:genetics*; D016229:Amyloid beta-Peptides / Q000378:metabolism*; D016564:Amyloid beta-Protein Precursor / Q000235:genetics*; D000818:Animals; D018955:CD36 Antigens / Q000235:genetics* / Q000378:metabolism; D004195:Disease Models, Animal; D018450:Disease Progression; D005091:Exons; D015316:Genetic Therapy; D006801:Humans; D000860:Hypoxia; D016086:Lentivirus; D051379:Mice; D008822:Mice, Transgenic; D017628:Microglia / Q000201:enzymology / Q000378:metabolism; D051267:NF-E2-Related Factor 2 / Q000235:genetics*; D018384:Oxidative Stress / Q000235:genetics*; D015854:Up-Regulation
D016229:Amyloid beta-Peptides; D016564:Amyloid beta-Protein Precursor; D018955:CD36 Antigens; D051267:NF-E2-Related Factor 2; C495635:NFE2L2 protein, human