How Does HIV Affect the Brain?

HIV may cause dementia by affecting how brain cells grow and die says study in rats

(RxWiki News) HIV-related dementia, known as AIDS dementia complex, can create memory problems and changes in behavior. Scientists are trying to understand how HIV affects the brain.

A recent study using rats found that HIV caused brain degeneration. HIV in the brain affected factors that promote cell growth and factors that affect cell death.

This might help explain why HIV can cause dementia and help researchers to find new treatments.

"Talk to your doctor about the signs of HIV-related dementia."

HIV-related dementia can start as trouble concentrating and poor muscle coordination. Later, it can create memory problems, word-finding issues, confusion and changes in behavior.

At the latest stages, it can affect balance and vision. Currently, antiretroviral treatment is the only known treatment for HIV-related dementia.

HIV can affect the brain, but scientists are not sure how it is doing damage to the brain to cause dementia.

To look at how HIV damages brain cells, Alessia Bachis, PhD, of the Department of Neuroscience at Georgetown University Medical Center, used rat brain cells.

The brain has a complex set of factors that help promote brain cell growth and control brain cell death. These factors work together to keep brain cells healthy and get rid of the ones that aren’t.

The researchers found that HIV released a protein. When that protein came in contact with brain cells it caused a protective factor to decrease and a damaging factor to increase.

The net result was that more brain cells died because there was not enough of the protective factor to keep brain cells growing and healthy.

The authors of this study also looked at the brains of people who had died with HIV and signs of dementia. They found that the same factors that were changed in the rat brain cells were out of balance in the human brains as well.

Together, the authors concluded that HIV proteins cause a shift in the factors that control brain cell growth and death.  The shift was in favor of cell death, which leads to cognitive and motor issues.

Finding out about this pathway may help lead to new therapies or screening risk for HIV- related dementia.

This study was published in the July 11 issue of the Journal of Neuroscience.

The study was funded by Health and Human Services Grants and the Latham Trust Fund.  No conflicts of interest were disclosed.

Review Date: 
September 13, 2012