Common viruses may be triggering the onset of Alzheimer’s disease

(Science Daily) –– Alzheimer’s disease can begin almost imperceptibly, often masquerading in the early months or years as forgetfulness that is common in older age. What causes the disease remains largely a mystery.

But researchers at Tufts University and the University of Oxford, using a three-dimensional human tissue culture model mimicking the brain, have shown that varicella zoster virus (VZV), which commonly causes chickenpox and shingles, may activate herpes simplex (HSV), another common virus, to set in motion the early stages of Alzheimer’s disease.

Normally HSV-1 — one of the main variants of the virus — lies dormant within the neurons of the brain, but when it is activated it leads to accumulation of tau and amyloid beta proteins, and loss of neuronal function — signature features found in patients with Alzheimer’s. (…)