June 18, 2008

Alzheimer's Protein Tied to HIV Progression

WEDNESDAY, June 18 (HealthDay News) -- A protein linked to Alzheimer's disease also plays a role in HIV progression by promoting entry of the virus into cells, U.S. researchers say.

"The apoE4 protein is the greatest known genetic risk factor to Alzheimer's disease. However, its role in infectious diseases has been less well-defined," study author Robert W. Mahley, president of the Gladstone Institutes, said in a prepared statement.

There are three different forms of ApoE. The genetic variant that leads to the production of the apoE4 protein is present in about 15 percent of people.

In this study, the researchers analyzed 1,267 HIV-positive people and 1,132 people without HIV. They found that HIV patients with two copes of the apoE4 allele had a much faster disease course and progression to death than those with two copies of the apoE3 allele.

While apoE4 helped HIV invade cells, it wasn't associated with increased incidence of HIV-associated dementia.

The findings, published in the journal Proceedings of the National Academy of Sciences, suggest a drug that converts apoE4 to an apoE3-like molecule may prove effective in treating people with HIV. Gladstone researchers are currently trying to develop such a drug for treating Alzheimer's disease.

"Although we suspected that apoE4 had a role in infectious disease, this aspect of the study is very exciting for us, because we already have studies under way to find small molecules that make apoE4 more like apoE3. Now those potential new drugs may have more value than we originally thought," Mahley said.

More information

The U.S. Centers for Disease Control and Prevention has more about HIV/AIDS.

-- Robert Preidt
SOURCE: Gladstone Institutes, news release, June 16, 2008
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