Mitochondrial toxic effects of Aβ through mitofusins in the early pathogenesis of Alzheimer's disease.
Mitochondrial dysfunction has been implicated in the pathogenesis of Alzheimer's disease (AD). However, it is obscure how amyloid-beta (Aβ) can impair mitochondria in the early stage of AD pathology. Using PrP-hAPP/hPS1 double-transgenic AD mouse model, we find that abnormal mitochondrial morphology and damaged mitochondrial structure in hippocampal neurons appear in the early stage of AD-like disease development. We also find consistent mitochondrial abnormalities in the SH-SY5Y cells, which express amyloid precursor protein (APP) Swedish mutation (APPsw) and have been used as a cell model of the early-onset AD. Significant changes of mitofusin GTPases (Mfn1 and Mfn2) were detected both in the PrP-hAPP/hPS1 brains and SH-SY5Y cells. Moreover, our results show that Aβ accumulation in neurons of PrP-hAPP/hPS1 mice can affect the neurogenesis prior to plaque formation. These findings suggest that mitochondrial impairment is a very early event in AD pathogenesis and abnormal expression of Mfn1 and Mfn2 caused by excessive intracellular Aβ is the possible molecular mechanism. Interestingly, L-theanine has significant effects on regulating mitochondrial fusion proteins in SH-SY5Y (APPsw) cells. Overall, our results not only suggest a new early mechanism of AD pathogenesis but also propose a preventive candidate, L-theanine, for the treatment of AD.
State Key Laboratory of Brain and Cognitive Sciences, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Chaoyang District, Beijing, 100101, China.
Zhaofei
Z
Wu
Yushan
Y
Zhu
Xingshui
X
Cao
Shufeng
S
Sun
Baolu
B
Zhao
D000544:Alzheimer Disease / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D016229:Amyloid beta-Peptides / Q000378:metabolism*; D016564:Amyloid beta-Protein Precursor / Q000378:metabolism; D000818:Animals; D004195:Disease Models, Animal; D020558:GTP Phosphohydrolases / Q000378:metabolism*; D006624:Hippocampus / Q000378:metabolism / Q000473:pathology*; D051379:Mice; D008822:Mice, Transgenic; D008928:Mitochondria / Q000378:metabolism / Q000473:pathology*; D009474:Neurons / Q000378:metabolism / Q000473:pathology*; D053764:Presenilin-1 / Q000235:genetics / Q000378:metabolism
D016229:Amyloid beta-Peptides; D016564:Amyloid beta-Protein Precursor; D053764:Presenilin-1; D020558:GTP Phosphohydrolases; C488750:Mfn1 protein, mouse; C488751:Mfn2 protein, mouse