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HIV-1 Nef increases astrocyte sensitivity towards exogenous hydrogen peroxide.

ABSTRACT: BACKGROUND: HIV-1 infected individuals are under chronic exposure to reactive oxygen species (ROS) considered to be instrumental in the progression of AIDS and the development of HIV-1 associated dementia (HAD). Astrocytes support neuronal function and protect them against cytotoxic substances including ROS. The protein HIV-1 Nef, a progression factor in AIDS pathology is abundantly expressed in astrocytes in patients with HAD, and thus may influence its functions. RESULTS: Endogenous expressed HIV-1 Nef leads to increased sensitivity of human astrocytes towards exogenous hydrogen peroxide but not towards TNF-alpha. Cell death of nef-expressing astrocytes exposed to 10 ?M hydrogen peroxide for 30 min occurred within 4 h. CONCLUSION: HIV-1 Nef may contribute to neuronal dysfunction and the development of HAD by causing death of astrocytes through decreasing their tolerance for hydrogen peroxide.

SUBMITTER: Masanetz S

PROVIDER: S-EPMC3038946 | biostudies-literature | 2011

REPOSITORIES: biostudies-literature

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HIV-1 Nef increases astrocyte sensitivity towards exogenous hydrogen peroxide.

Masanetz Sabine S Lehmann Michael H MH

Virology journal 20110122

<h4>Background</h4>HIV-1 infected individuals are under chronic exposure to reactive oxygen species (ROS) considered to be instrumental in the progression of AIDS and the development of HIV-1 associated dementia (HAD). Astrocytes support neuronal function and protect them against cytotoxic substances including ROS. The protein HIV-1 Nef, a progression factor in AIDS pathology is abundantly expressed in astrocytes in patients with HAD, and thus may influence its functions.<h4>Results</h4>Endogeno ...[more]

PMID: 21255447

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