Alzheimer病与Parkinson病机制之间的联系被识
&nbps;&nbps;&nbps;&nbps;WESTPORT, CT (Reuters Health) - Supporting clinical observations of the co-occurrence of Alzheimer's disease symptoms and Parkinson's disease symptoms in some patients, evidence of a common pathway between the diseases is published in the September 25th early edition of Proceedings of the National Academy of Sciences.
&nbps;&nbps;&nbps;&nbps;The beta-amyloid peptides that accumulate in Alzheimer's disease plaques enhance buildup of the alpha-synuclein protein found in the brains of Parkinson's disease patients, according to Dr. Eliezer Masliah, from the University of California at San Diego in La Jolla, and colleagues. They studied transgenic mice engineered to express human beta-amyloid peptides, alpha-synuclein, or both.
&nbps;&nbps;&nbps;&nbps;Mice that expressed both proteins showed severe deficits in learning and memory and developed motor deficits sooner than mice that only expressed alpha-synuclein, the researchers determined.
&nbps;&nbps;&nbps;&nbps;Prominent age-dependent degeneration of presynaptic terminals and cholinergic neurons was noted in doubly transgenic mice. These mice also had more alpha-synuclein neuronal inclusions than mice that only expressed alpha-synuclein. Further analysis revealed that the inclusions in doubly transgenic mice were fibrillar, while those in alpha-synuclein mice were amorphous, according to the report.
&nbps;&nbps;&nbps;&nbps;In vitro assays demonstrated similar results showing that beta-amyloid promoted aggregation and intraneuronal accumulation of alpha-synuclein.
&nbps;&nbps;&nbps;&nbps;"It remains to be determined whether the neuronal deficits in these models and the corresponding human diseases are dependent on fibrillar or prefibrillar forms of beta-amyloid and alpha-synuclein," Dr. Masliah's team notes.
&nbps;&nbps;&nbps;&nbps;"In either case," the researchers state, "the pathogenic interactions between beta-amyloid and alpha-synuclein demonstrated here suggest that drugs aimed at blocking the accumulation of beta-amyloid or alpha-synuclein might benefit a broader spectrum of neurodegenerative disorders than previously anticipated.", 百拇医药
&nbps;&nbps;&nbps;&nbps;The beta-amyloid peptides that accumulate in Alzheimer's disease plaques enhance buildup of the alpha-synuclein protein found in the brains of Parkinson's disease patients, according to Dr. Eliezer Masliah, from the University of California at San Diego in La Jolla, and colleagues. They studied transgenic mice engineered to express human beta-amyloid peptides, alpha-synuclein, or both.
&nbps;&nbps;&nbps;&nbps;Mice that expressed both proteins showed severe deficits in learning and memory and developed motor deficits sooner than mice that only expressed alpha-synuclein, the researchers determined.
&nbps;&nbps;&nbps;&nbps;Prominent age-dependent degeneration of presynaptic terminals and cholinergic neurons was noted in doubly transgenic mice. These mice also had more alpha-synuclein neuronal inclusions than mice that only expressed alpha-synuclein. Further analysis revealed that the inclusions in doubly transgenic mice were fibrillar, while those in alpha-synuclein mice were amorphous, according to the report.
&nbps;&nbps;&nbps;&nbps;In vitro assays demonstrated similar results showing that beta-amyloid promoted aggregation and intraneuronal accumulation of alpha-synuclein.
&nbps;&nbps;&nbps;&nbps;"It remains to be determined whether the neuronal deficits in these models and the corresponding human diseases are dependent on fibrillar or prefibrillar forms of beta-amyloid and alpha-synuclein," Dr. Masliah's team notes.
&nbps;&nbps;&nbps;&nbps;"In either case," the researchers state, "the pathogenic interactions between beta-amyloid and alpha-synuclein demonstrated here suggest that drugs aimed at blocking the accumulation of beta-amyloid or alpha-synuclein might benefit a broader spectrum of neurodegenerative disorders than previously anticipated.", 百拇医药