TY - JOUR
T1 - HIV-1 tat-mediated induction of platelet-derived growth factor in astrocytes
T2 - Role of early growth response gene 1
AU - Bethel-Brown, Crystal
AU - Yao, Honghong
AU - Callen, Shannon
AU - Lee, Young Han
AU - Dash, Prasanta K.
AU - Kumar, Anil
AU - Buch, Shilpa
PY - 2011/4/1
Y1 - 2011/4/1
N2 - HIV-associated neurologic disorders (HAND) are estimated to affect almost 60% of HIV-infected individuals. HIVencephalitis, the pathologic correlate of the most severe form of HAND, is often characterized by glial activation, cytokine-chemokine dysregulation, and neuronal damage and loss. However, the severity of HIV encephalitis correlates better with glial activation rather than viral load. Using the macaque model, it has been demonstrated that SIV encephalitis correlates with increased expression of the mitogen platelet-derived growth factor (PDGF) B chain in the brain. The goal of this study was to explore the role of PDGF-B chain in HIVassociated activation and proliferation of astrocytes. Specifically, the data demonstrate that exposure of rat and human astrocytes to the HIV-1 protein Tat resulted in the induction of PDGF at both the mRNA and protein levels. Furthermore, PDGF-BB induction was regulated by activation of ERK1/2 and JNK signaling pathways and the downstream transcription factor early growth response 1. Chromatin immunoprecipitation assays demonstrated binding of Egr-1 to the PDGF-B promoter. Exposure of astrocytes to PDGF-BB in turn led to increased proliferation and the release of proinflammatory cytokines MCP-1 and IL-1β. Because astrogliosis is linked to disease severity, understanding its regulation by PDGF-BB could aid in the development of therapeutic intervention strategies for HAND.
AB - HIV-associated neurologic disorders (HAND) are estimated to affect almost 60% of HIV-infected individuals. HIVencephalitis, the pathologic correlate of the most severe form of HAND, is often characterized by glial activation, cytokine-chemokine dysregulation, and neuronal damage and loss. However, the severity of HIV encephalitis correlates better with glial activation rather than viral load. Using the macaque model, it has been demonstrated that SIV encephalitis correlates with increased expression of the mitogen platelet-derived growth factor (PDGF) B chain in the brain. The goal of this study was to explore the role of PDGF-B chain in HIVassociated activation and proliferation of astrocytes. Specifically, the data demonstrate that exposure of rat and human astrocytes to the HIV-1 protein Tat resulted in the induction of PDGF at both the mRNA and protein levels. Furthermore, PDGF-BB induction was regulated by activation of ERK1/2 and JNK signaling pathways and the downstream transcription factor early growth response 1. Chromatin immunoprecipitation assays demonstrated binding of Egr-1 to the PDGF-B promoter. Exposure of astrocytes to PDGF-BB in turn led to increased proliferation and the release of proinflammatory cytokines MCP-1 and IL-1β. Because astrogliosis is linked to disease severity, understanding its regulation by PDGF-BB could aid in the development of therapeutic intervention strategies for HAND.
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U2 - 10.4049/jimmunol.1002235
DO - 10.4049/jimmunol.1002235
M3 - Article
C2 - 21368226
AN - SCOPUS:79954992762
SN - 0022-1767
VL - 186
SP - 4119
EP - 4129
JO - Journal of Immunology
JF - Journal of Immunology
IS - 7
ER -