A review of medical records suggests that it could be possible to transmit Alzheimer’s through certain medical procedures. If this is proven, then other neurodegenerative diseases may similarly be transferable. This finding has created concerns that progressive diseases of the brain can be passed on from one person to another.
To avoid the ringing of alarm bells, the findings related to specific medical procedures and require a specific set of environmental circumstances, along with a person suffering from a given disease.
The possibility of transfer has been reported to the journal Nature. The paper is titled “Evidence for human transmission of amyloid-β pathology and cerebral amyloid angiopathy.”
The report explains that during the period from 1958 to 1985, 30,000 people worldwide — mainly children — were administered injections of human growth hormone. This was designed to treat short stature. The hormone was extracted from thousands of human pituitary glands, with the source material being recently deceased people.
It now appears, The Economist summarizes, that some of these hormonal extracts contained prions. Around one in 16 of the children developed the brain disorder Creutzfeldt-Jakob disease (CJD). The concern with CJD centered on prions.
Prions (“proteinaceous infectious particles”), as Digital Journal has explained previously, are types of protein folded in atypical and complex ways. Some prions can replicate by instructing other proteins in the human body to misfold in a similar fashion. Despite the ability to replicate, prions are not classed as living entities.
A current review of the medical records of those who died from CJD has revealed deposits of the amyloid beta protein in the brains of the deceased. This protein is associated with the development of Alzheimer’s disease. Because Alzheimer’s is rare in people aged below 60, the contemporary researchers from the Medical Research Council delved deeper.
It appears that when the human growth hormone was injected it not only contained prions, but also amyloid beta protein fragments. These fragments had come from the original cadaver donors. There are some similarities existing between prions and amyloid precursor protein which can be transformed into beta amyloid.
The researchers point out that their work is only an observational study based on a practice that no longer takes place and on samples that any many decades old (i.e. it is not medical “proof”). Nonetheless, it opens up a new and important line of inquiry as to whether some human-to-human transfers of body material can lead to the risk of infectious agents like prions (misfolded proteins) and other proteins, such as those associated with neurodegenerative diseases like Alzheimer’s and Parkinson’s. To date, there is no evidence that blood transfusions are a concern, but types of hormone replacement therapy should, at least, be examined. Other historical medical records could prove interesting when re-analyzed in light of these new observational findings.
In related news, drug company Neurimmune, together with partner organization Biogen, have begun a Phase III study into a novel Alzheimer’s treatment called Aducanumab.