Research Links Cold Sores to Alzheimer's

New research is linking common cold sores to Alzheimer's disease, and medical

experts are advising those who contract them to quickly treat them.

Scientists from labs at Brown University, the University of New Mexico, and the

House Ear Institute developed a new way of observing infections of herpes simplex

virus type 1 (HSV1) growing inside cells and discovered how the virus interacts with

amyloid precursor protein (APP), the major component of senile plaques found in the

brains of Alzheimer's disease patients.

"Clinicians have seen a link between HSV1 infection and Alzheimer's disease in

patients, so we wanted to investigate what might be going on in the body that would

account for this," Dr. Shi-Bin Cheng of the Alpert Medical School at Brown

University, says in a press release. "What we were able to see in the lab strongly

suggests a causal link between HSV1 and Alzheimer's disease."

A latent form of HSV1 lives inside nerve cells. The virus infects mucous membranes,

like the lips and eyes, causes the common cold sore, and generates viral particles,

says Dr. Elaine Bearer of the University of New Mexico School of Medicine and

principal investigator of the study.

"These viral particles burst out of the cells of the mucous membrane and enter

sensory nerve cells where they travel inside the nerve toward the brain," she says

in the press release. "We now can see this cellular transportation system and watch

how the newly formed virus engages cellular APP on its journey out of the cell."

The interaction between APP and HSV1 showed "a mechanism by which HSV1 infection

leads to Alzheimer's disease," the statement said.

"It's no longer a matter of determining whether HSV1 is involved in cognitive

decline, but rather how significant this involvement is," Bearer says. "We'll need

to investigate anti-viral drugs used for acute herpes treatment to determine their

ability to slow or prevent cognitive decline."

Cold sore sufferers should treat blisters as soon as possible so that the HSV1

quickly returns to dormancy, researchers advised. While there is no known cold sore

cure, over-the-counter products and anti-viral drugs can help with pain, speed

healing, and may prevent recurrence of the sores, which usually last about 10 days,

according to WebMD.com.

The research was published in the March 31 issue of PLoS ONE, the magazine of the

Public Library of Science.

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