Cybrids in Alzheimer's disease: a cellular model of the disease?
The mitochondrial electron transport chain enzyme cytochrome c oxidase (COX) is defective in patients with sporadic Alzheimer's disease (AD). This defect arises from the mutation of mitochondrial DNA (mtDNA). To develop a tissue culture system that would express this genetically derived bioenergetic lesion and permit characterization of its functional consequences, we depleted Ntera2/D1 (NT2) teratocarcinoma cells of endogenous mtDNA and repopulated them with platelet mtDNA from AD patients. Cytochrome c oxidase activity was depressed in the resulting AD cytoplasmic hybrids (cybrids) compared with cybrids prepared with mtDNA from non-AD controls. Reactive oxygen species (ROS) production and free radical scavenging enzyme activities were significantly elevated in AD cybrids. A COX defect in NT2 AD cybrid lines indicates that AD patients possess mtDNA COX gene mutations that are sufficient for determining this biochemical lesion. Expression of unique functional characteristics (increased ROS production and free radical scavenging enzyme activities) relevant to neurodegeneration demonstrates the utility of these cells in defining AD pathophysiology at a cellular level. This in vitro tissue culture model of AD may prove useful in drug screening.
Swerdlow
R H
RH
Center for the Study of Neurodegenerative Diseases and the Department of Neurology, University of Virginia Health Sciences Center, Charlottesville 22908, USA.
Parks
J K
JK
Cassarino
D S
DS
Maguire
D J
DJ
Maguire
R S
RS
Bennett
J P
JP
Davis
R E
RE
Parker
W D
WD
D000544:Alzheimer Disease / Q000235:genetics* / Q000473:pathology*; D001921:Brain / Q000473:pathology*; D003593:Cytoplasm / Q000502:physiology; D004272:DNA, Mitochondrial / Q000235:genetics / Q000378:metabolism; D003576:Electron Transport Complex IV / Q000235:genetics / Q000378:metabolism; D018014:Gene Transfer Techniques; D005821:Genetic Techniques; D006801:Humans; D006824:Hybridization, Genetic; D009154:Mutation; D017382:Reactive Oxygen Species / Q000378:metabolism; D012016:Reference Values; D018243:Teratocarcinoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D014407:Tumor Cells, Cultured / Q000378:metabolism
D004272:DNA, Mitochondrial; D017382:Reactive Oxygen Species; D003576:Electron Transport Complex IV