A surprising link has been discovered between viral infections, namely the herpes simplex virus, and Alzheimer’s disease. But more studies are needed to identify how it contributes to the development of the disease.
Researchers at the University of Pittsburgh, in the USA, discovered a link between the herpes simplex virus (HSV-1), concluding that viral infections may play an important role in the development of the disease.
In the published in the scientific journal Cell Reports, scientists also concluded that tau protein which was seen as harmless in Alzheimer’s, “may initially protect the brain from the virus, but later contribute to brain damage“.
Tau protein is a protein that stabilizes structures essential for the maintenance of form and function of neurons in the central nervous system.
Under normal conditions, tau helps in the molecular processes of memory formation in the healthy brain.
But when this protein is defective or hyperphosphorylated, it can lead to the appearance of diseases such as Alzheimer’s disease.
“Our study challenges the conventional view of [proteína] tau as being exclusively harmful, showing that it may initially act as part of brain immune defense“, says the main author of the research, Or Shemesh, assistant professor in the Department of Ophthalmology at the University of Pittsburgh, at the institution.
“Complex interaction” between infections and neurodegenerative diseases
The researchers “identified forms of proteins related to HSV-1 in Alzheimer’s brain sampleswith greater amounts of viral proteins co-localized with tangles of phosphorylated tau – one of the characteristics of the pathology – in regions of the brain especially vulnerable to the disease”, the statement further explains.
Analyzes carried out on miniature models of human brains “suggested that HSV-1 infection could modulate brain tau protein levels and regulate their function, a protective mechanism that appeared to decrease post-infection death of human neurons,” the researchers add.
“These findings emphasize the complex interaction between infections, immune responses and neurodegeneration, offering a new perspective and potential new targets for therapeutic development”, explains Shemesh further.
It is still necessary to unravel how herpes contributes to Alzheimer’s
However, scientists were unable to reveal the “precise mechanisms” through which simplex influences tau protein and thus contributes to Alzheimer’s disease.
The researchers hope to carry out more research to explore this clue, namely to test “potential therapeutic strategies” that target viral proteins, and “tune the brain’s immune response”.
They also aim to investigate whether similar mechanisms are involved in the development of other neurodegenerative diseases, such as aea.
