title: 4-Hydroxy-2-nonenal induces mitochondrial dysfunction and aberrant axonal outgrowth in adult sensory neurons that mimics features of diabetic neuropathy.
abstract: Modification of proteins by 4-hydroxy-2-nonenal (4-HNE) has been proposed to cause neurotoxicity in a number of neurodegenerative diseases, including distal axonopathy in diabetic sensory neuropathy. We tested the hypothesis that exposure of cultured adult rat sensory neurons to 4-HNE would result in the formation of amino acid adducts on mitochondrial proteins and that this process would be associated with impaired mitochondrial function and axonal regeneration. In addition, we compared 4-HNE-induced axon pathology with that exhibited by neurons isolated from diabetic rats. Cultured adult rat dorsal root ganglion (DRG) sensory neurons were incubated with varying concentrations of 4-HNE. Cell survival, axonal morphology, and level of axon outgrowth were assessed. In addition, video microscopy of live cells, western blot, and immunofluorescent staining were utilized to detect protein adduct formation by 4-HNE and to localize actively respiring mitochondria. 4-HNE induced formation of protein adducts on cytoskeletal and mitochondrial proteins, and impaired axon regeneration by approximately 50% at 3 microM while having no effect on neuronal survival. 4-HNE initiated formation of aberrant axonal structures and caused the accumulation of mitochondria in these dystrophic structures. Neurons treated with 4-HNE exhibited a distal loss of active mitochondria. Finally, the distal axonopathy and the associated aberrant axonal structures generated by 4-HNE treatment mimicked axon pathology observed in DRG sensory neurons isolated from diabetic rats and replicated aspects of neurodegeneration observed in human diabetic sensory neuropathy.
authors: Division of Neurodegenerative Disorders, St Boniface Hospital Research Centre, R4046-351 Tache Ave, Winnipeg, MB, R2H 2A6, Canada.
authors: Eli
authors: E
authors: Akude
authors: Elena
authors: E
authors: Zherebitskaya
authors: Subir K
authors: SK
authors: Roy Chowdhury
authors: Kimberly
authors: K
authors: Girling
authors: Paul
authors: P
authors: Fernyhough
mesh_terms: D000447:Aldehydes / Q000378:metabolism / Q000633:toxicity*; D000818:Animals; D001369:Axons / Q000187:drug effects*; D002478:Cells, Cultured; D015853:Cysteine Proteinase Inhibitors / Q000633:toxicity*; D003921:Diabetes Mellitus, Experimental / Q000473:pathology*; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D005727:Ganglia, Spinal / Q000473:pathology; D007211:Indoles; D008297:Male; D051379:Mice; D008928:Mitochondria / Q000187:drug effects*; D016900:Neurofilament Proteins / Q000378:metabolism; D009930:Organic Chemicals / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D011984:Sensory Receptor Cells / Q000187:drug effects* / Q000473:pathology
chemical_list: D000447:Aldehydes; D015853:Cysteine Proteinase Inhibitors; D007211:Indoles; D016900:Neurofilament Proteins; D009930:Organic Chemicals; C107472:red dye CMXRos; C051774:neurofilament protein H; C007293:DAPI; C027576:4-hydroxy-2-nonenal