Researchers believe that they have identified the neural decline mechanism associated with HIV-associated dementia.
The discovery was made as part of a wider investigation into why patients who use antiretroviral therapy and show no signs of AIDS develop serious depression, as well as significant problems with memory, learning and motor function.
According to those involved in the study, the findings may ultimately lead to therapeutic solutions for other brain ailments, including those associated with age.
Dr Italo Mocchetti, lead investigator on the study, stated: "We believe we have discovered a general mechanism of neuronal decline that even explains what happens in some elderly folks.
"The HIV-infected patients who develop this syndrome are usually quite young, but their brains act old."
Researchers observed that HIV stops the brain from producing sufficient amounts of a protein growth factor known as mature brain derived neurotrophic factor (BDNF).
BDNF acts as a food for brain neurons and low levels of the factor shortens the axons in the brain and their branches that neurons use to connect to each other. This leads to neuron death and dementia.
A study previously suggested that a mutation of HIV in the envelope gene was a cause of HIV-associated dementia.
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