The controversial theory that pathogens can contribute at least in part to Alzheimer's disease has been building steam with a stack of evidence behind it
A global team of scientists have collaborated on a new editorial released in the Journal of Alzheimer's Disease - highlighting the need for more research on potential viral and bacterial contributions to Alzheimer's pathology.
A radical theory?
Science is built on theories, but radical ones can take some time to adjust to. While no-one is claiming microbes are the sole cause of Alzheimer's disease, a steady stream of research has been supporting a causative role for a while now, it's simply taken a long time to become accepted. Now that over 400 clinical trials against Alzheimer's based on more classical models have proved largely ineffective, greater understanding of the disease is resulting in a greater acceptance of more unusual evidence.
This isn't new
The finding that pathogens may play a part in Alzheimer's onset has been fiercely resisted, but we already know viruses can trigger specific cancer types and bacteria can form stomach ulcers. When you place the theory in context, it's actually not so radical after all.
“We are saying there is incontrovertible evidence that Alzheimer’s Disease has a dormant microbial component, and that this can be woken up by iron dysregulation. Removing this iron will slow down or prevent cognitive degeneration – we can’t keep ignoring all of the evidence”
Dormant microbes can be found in red blood cells, and previous work has suggested fungal cells may even play a role in Alzheimer's (see here). Now that so much evidence has amassed implicating a range of pathogens including the herpes simplex virus in disease pathology, more people are calling for greater study into the area. To be clear, at this point no-one knows whether this phenomenon is a consequence or potential cause of the disease, but it could be that immune deterioration causes problems or that these microbial elements lead to greater inflammation. It certainly warrants greater study in any case.
"The microbial presence in blood may also play a fundamental role as causative agent of systemic inflammation, which is a characteristic of Alzheimer’s disease – particularly, the bacterial cell wall component and endotoxin, lipopolysaccharide. Furthermore, there is ample evidence that this can cause neuroinflammation and amyloid-β plaque formation”
Read more at Neuroscience News