Researchers from Tufts University in the US presented recent findings that support the hypothesis that Alzheimer’s disease may be caused by a virus. The strain in question is very common because it is the Varicella-zoster virus (VZV)
Approximately 225,000 people declared in France Every year, after the age of 65. Although this type of dementia is common, its origin is still hotly debated among specialists. There are all the same points of consensus: amyloid plaques and clusters in involved in the onset of symptoms typical of Alzheimer’s disease, and who seizes Patients exacerbate this .
To explain these notes, . factors It appears to have an important role in sporadic cases of Alzheimer’s disease, which is most common, but results in downregulation of amyloid protein synthesis or interference with a Most of the time a virus can have an underlying effect.
Experiments in the laboratory on cultured neurons
To confirm this hypothesis, they infectedHuman neurons were labeled with viruses and looked for signs specific to Alzheimer’s disease: amyloid plaques and tau clumps, glia (proliferation in the brain) and neuritis. Their results show that VZV alone does not cause the formation of amyloid plaques and tau clumps, like HSV-1, but rather causes neuroinflammation and glia. This, according to scientists, indicates an indirect action of the VZV virus. In addition, they note that infection of cells, in which HSV-1 is dormant, by VZV reactivates the latter and causes changes typical of Alzheimer’s disease. ” It’s a double whammy from two very common and generally harmless viruses, but lab studies suggest that if additional exposure to VZV awakens dormant HSV-1, it can cause problems. Dana Kearns says.
These experiments alone are not strong enough to confirm a causal relationship between Alzheimer’s disease and VZV and HSV-1 viruses, even if the observations point in this direction. Furthermore, the various hypotheses being studied about the origin of Alzheimer’s disease are not necessarily conflicting. Viral infection could be a factor to consider in Alzheimer’s disease, among other things.