title: The Role of Mitochondrial Aldehyde Dehydrogenase 2 (ALDH2) in Neuropathology and Neurodegeneration.
abstract: Aldehydes-induced toxicity has been implicated in many neurodegenerative diseases. Exposure to reactive aldehydes from (1) alcohol and food metabolism; (2) environmental pollutants, including car, factory exhausts, smog, pesticides, herbicides; (3) metabolism of neurotransmitters, amino acids and (4) lipid peroxidation of biological membrane from excessive ROS, all contribute to 'aldehydic load' that has been linked to the pathology of neurodegenerative diseases. In particular, the α, β-unsaturated aldehydes derived from lipid peroxidation, 4-hydroxynonenal (4-HNE), DOPAL (MAO product of dopamine), malondialdehyde, acrolein and acetaldehyde, all readily form chemical adductions with proteins, DNA and lipids, thus causing neurotoxicity. Mitochondrial aldehyde dehydrogenase 2 (ALDH 2) is a major aldehyde metabolizing enzyme that protects against deleterious aldehyde buildup in brain, a tissue that has a particularly high mitochondrial content. In this review, we highlight the deleterious effects of increased aldehydic load in the neuropathology of ischemic stroke, Alzheimer's disease and Parkinson's disease. We also discuss evidence for the association between ALDH2 deficiency, a common East Asianspecific mutation, and these neuropathologies. A novel class of small molecule aldehyde dehydrogenase activators (Aldas), represented by Alda-1, reduces neuronal cell death in models of ischemic stroke, Alzheimer's disease and Parkinson's disease. Together, these data suggest that reducing aldeydic load by enhancing the activity of aldehyde dehydrogenases, such as ALDH2, represents as a therapeutic strategy for neurodegenerative diseases.
authors.affiliation: Department of Chemical and Systems Biology, Stanford University, School of Medicine, Stanford CA 94305-5174 USA.
authors.forename: Che-Hong
authors.initials: CH
authors.lastname: Chen
authors.affiliation: Department of Chemical and Systems Biology, Stanford University, School of Medicine, Stanford CA 94305-5174 USA.
authors.forename: Amit U
authors.initials: AU
authors.lastname: Joshi
authors.affiliation: Department of Chemical and Systems Biology, Stanford University, School of Medicine, Stanford CA 94305-5174 USA.
authors.forename: Daria
authors.initials: D
authors.lastname: Mochly-Rosen
mesh_terms: D000071396:Aldehyde Dehydrogenase, Mitochondrial / Q000378:metabolism*; D000447:Aldehydes / Q000009:adverse effects; D000544:Alzheimer Disease / Q000201:enzymology* / Q000473:pathology; D002545:Brain Ischemia / Q000201:enzymology* / Q000473:pathology; D006801:Humans; D010300:Parkinson Disease / Q000201:enzymology* / Q000473:pathology
chemical_list: D000447:Aldehydes; C096127:ALDH2 protein, human; D000071396:Aldehyde Dehydrogenase, Mitochondrial