GFAP and brain injury: Experiments in HIV trans-activator of transcription (Tat) transgenic mice indicate that EGb 761 (a standardized formulation of GA extract) exhibits neuroprotective properties by down-regulating the expression of GFAP (Glial Fibrillary Acidic Proteins) in the brain, which negates the astrocytosis that occurs in response to HIV-related brain injuries.