January 22, 2005
Alzheimer brain damage 'reversed'Topics: Medicine
From BBCNews comes a report that scientists have reversed the damage caused to the brain by Alzheimer's disease during tests on mice. This approach has been undertaken before using passive anti-Abeta immunotherapy (Dec 2004)in transgenic mice when researchers at the University of South Florida determined that it reduced both diffuse and compact amyloid deposits, improved memory function and cleared early-stage phospho-tau aggregates.
In classic good-news/bad-news results, dramatic reductions of diffuse Abeta immunostaining and parenchymal congophilic amyloid deposits were observed after five months, indicating that even well-established amyloid deposits are susceptible to immunotherapy. However, cerebral amyloid angiopathy increased substantially with immunotherapy, and some deposits were associated with microhemorrhage. Reanalysis of results collected from an earlier time-course study demonstrated that these increases in vascular deposits were dependent on the duration of immunotherapy.
Yet, in another development published in the same month, while researchers agreed that the amyloid-beta (Abeta) peptide had a central role in the neurodegeneration of Alzheimer disease(AD) and that immunization of AD transgenic mice with Abeta(1-42) (Abeta(42)) peptide reduced both the spatial memory impairments and AD-like neuropathologic changes in these mice - therapeutic immunization with Abeta in patients with AD was shown to be effective in reducing Abeta deposition, but studies had to be discontinued owing to the development of an autoimmune, cell-mediated meningoencephalitis.
In the study that is the subject of the BBC News artice, neither the issue of cell-mediated meningoencephalitis or those of cerebral amyloid angiopathy and microhemorrhage were mentioned.These events seem to be related to the duration of the immunotherapy and the US team in the BBC article seems to have significantly shortened the duration of therapy in their study (days rather than weeks or months), so without more information than is provided in the article we can't know the duration of this most recent study, it's study parameters, or any adverse effects resulting from the therapy(was unable to find the article in Medline - could be in submission stage).
BBC News/Health Jan 22
The US team used an antibody to remove the build up of potentially damaging deposits from the area of the brain responsible for memory and cognition.
The treatment reversed the nerve cell damage in days, Washington University School of Medicine researchers said.
UK experts described the findings, published in the Journal of Clinical Investigation, as "exciting".
Prior to the study, it was thought that once the damage had been caused to the brain there was no way of repairing it. Read more...
Posted by Hyscience at January 22, 2005 1:48 PM
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- Alzheimer brain damage 'reversed' - Jan 22, 2005