The contribution of oxidative stress in apoptosis of human-cultured astroglial cells induced by supernatants of HIV-1-infected macrophages

Abstract

Apoptosis of neurons and astrocytes has been found in patients undergoing AIDS dementia complex. We demonstrated that supernatants from human primary macrophages (M/M) infected by HIV-1 lead human astroglial cells to oxidative stress, as shown by elevated levels of malondialdehyde, and then to apoptosis. Electron microscopy of astrocytes shortly incubated with HIV-1-infected M/M supernatants showed apoptotic blebbing, cytoplasmic loss, and chromatin condensation. Apoptosis was antagonized by pretreating astrocytes with the nonpeptidic superoxide dismutase (SOD) mimetic M40401 but not with anti-HIV-1 compounds, thus showing that apoptosis of astrocytes driven by HIV-1-infected M/M supernatants is mainly mediated by abnormal production of superoxide anions without relationship to HIV-1 replication in such cells. Overall results support the role of oxidative stress mediated by HIV-1-infected M/M as one of the leading causes of neurodegeneration in patients with HIV-1 and suggest the use of nonpeptidic SOD mimetics to counteract HIV-1-related neurological disorders.