Proteins produced by HIV can accelerate the death of neurons in the brain and central nervous system, which can lead to the development of AIDS-related dementia, according to a study in the online edition of the Proceedings of the National Academy of Sciences. The proteins activate two biochemical pathways that play a role in the death of neurons, report researchers at Philadelphia's Thomas Jefferson University. Lead researcher Roger Pomerantz and his colleagues, who had previously found that certain HIV proteins are toxic to neurons, set up a controlled test to see if the body's natural toxins or the viral proteins were responsible for neuron death in AIDS-related dementia. "We feel that it's mainly the virus and viral proteins causing neuronal cell death and now may know the precise pathways involved," Pomerantz told the Seattle Post-Intelligencer. "Now we not only have the ability to block [the dementia process] by blocking the virus, but we also have a way of designing drugs to specifically protect neurons" even if HIV is present.