Antioxidant drugs may help prevent the effects of HIV on the brain, according to a preliminary study using cell cultures. The study was presented during the American Academy of Neurology's 53rd Annual Meeting in Philadelphia, PA, May 5-11, 2001. "Dementia is one of the most feared complications of HIV infection," said study author and neurologist Avindra Nath, MD, of the University of Kentucky in Lexington. "The newer antiretroviral drugs help reverse it to some extent, but not completely, so this is a potentially exciting approach."
For the study, researchers first needed to find out how HIV affects healthy brain cells. They placed healthy brain cells, in cultures with cerebrospinal fluid from 30 HIV patients with dementia, 16 HIV patients without dementia and 20 patients with other neurological disorders as a control group.
They developed a sensitive test to determine how the cerebrospinal fluid (CSF) affected the cells' mitochondria, which produce energy for the cells. Proper mitochondrial functioning is necessary for physical strength and consciousness; even subtle problems can cause weakness and cognitive difficulties.
The researchers found that HIV infection decreases the activity level of the mitochondria, with the amount of damage increasing as the dementia becomes severe. Next the researchers added antioxidant drugs to the cultures with CSF from patients with HIV dementia. They tested seven drugs separately to see if any of them would protect the mitochondria from the damaging effects of the CSF.
"Six of the drugs reversed the effects of the CSF toxicity," Nath said. "Much more work needs to be done to determine whether any of these drugs are actually effective for patients, but the potential is exciting."
Nath said the study adds support to a proposal for a multi-center clinical trial on the use of one of the drugs, L-deprenyl, in HIV-infected patients with dementia. Another drug, didox, is of special interest, Nath said, because it also has antiretroviral activity, or is able to suppress the replication of the AIDS virus.
