HIV Kills Brain Cells, Prevents Stem Cell Division, Study Says
HIV kills brain cells and prevents stem cells from dividing and forming new cells, according to a study published Wednesday in the journal Cell Stem Cell, Reuters reports. The damage to cells contributes to HIV-associated dementia, which can cause confusion, sleep disturbance and memory loss (Reuters, 8/15).
Researchers from the University of California-San Diego and the Burnham Institute for Medical Research identified the protein gp120, which is found on the outside of HIV. The researchers found that gp120 damages brain cells and then prevents the formation of new cells in mice (Dayton, Australian, 8/16). "It's a double hit to the brain," Marcus Kaul -- an assistant professor of infectious diseases and immunology at UCSD and BIMR and a study researcher -- said in a statement, adding, "The HIV protein both causes brain injury and prevents its repair" (Reuters, 8/15). According to the Australian, although highly active antiretroviral therapy causes HIV-associated dementia to be less severe, the condition's prevalence has not declined with the advent of HAART. Bruce Brew -- head of neurology at St. Vincent's Hospital in Sydney, Australia -- said that about 20% of people living with AIDS develop HIV-associated dementia (Australian, 8/16). The condition also is becoming more common as HIV-positive people live longer because of antiretrovirals.
According to study author Stuart Lipton, the "breakthrough" in the research is that scientists were able to determine that HIV prevents stem cell division. Lipton added that the study is the "first time that the virus has ever been shown to affect stem cells." Kaul said the identification of gp120 could lead to treatments for HIV-associated dementia that involve "ramping up brain repair or protecting the repair mechanism" (Reuters, 8/15).
The study is available online.