We hypothesize that PDGF BB induced by HIV 1HIV 1 Tat can result in astrocytic ac tivation selleck chemical Y-27632 and release of MCP 1 and BBB disruption. The data demonstrate that the exposure of human astrocytes to HIV 1 LAI resulted in the induction of PDGF at both the mRNA and protein Inhibitors,Modulators,Libraries levels. To explicate the mechan isms involved in PDGF BBMCP 1 interaction, human astrocytes were then treated with PDGF BB and moni tored for expression of MCP 1. Utilizing Inhibitors,Modulators,Libraries pharmaco logical and genetic approaches we demonstrate the involvement of extracellular signal regulated kinase 12, c Jun N terminal kinase and p38 mitogen activated protein kinases, Phosphati dylinositol 3 kinase Akt pathways and the tran scription factor nuclear factor ��B in PDGF BB mediated induction of MCP 1 in astrocytes.

Because both PDGF Inhibitors,Modulators,Libraries BB and MCP 1 are known to affect the BBB and since astrocytic end feet processes are in close contact with the endothelia, we also addressed the func tional implications this may have on the BBB. Using pharmacological and neutralizing antibody approaches, we reveal that both Inhibitors,Modulators,Libraries PDGF BB and MCP 1 play critical roles in reducing the integrity of the BBB. These data highlight the role of PDGF BB in astrocytic release of MCP 1, which in turn, is critical for recruitment of monocytes across the BBB. Taken together, these studies underscore the role of PDGF signaling as a potential therapeutic target of HAND. Inhibitors,Modulators,Libraries Materials and methods Materials Recombinant human PDGF BB was purchased from R D Systems. All experiments involving the treatment of cells with exogenous PDGF BB were conducted under serum free conditions because serum induces PDGF.

STI 571, an inhibitor of tyrosine kinase receptors, was obtained from Novartis. The specific phosphatidinylinositol 3 kin ase inhibitor LY294002, mitogen activated pro tein kinase kinase inhibitor U0126 and p38 mitogen activated kinase inhibitor SB203558 were purchased from Promega. The JNK inhibitor SP600125 was purchased from leave a message Assay Designs. MCP 1 neutralizing antibody was obtained from eBioscience. The C C chemokine receptor type 2 antagonist, RS 102895, was purchased from Sigma. The chromatin immunoprecipitation assay kit was obtained from Upstate. Cell culture and cell lines The human astrocytic cell line A172were cul tured as described previously and maintained in Dulbeccos modified Eagles medium high glu cose medium containing 10% heated inactivated fetal bovine serum, 2 mM glutamine, penicillin, streptomycin, essential amino acids and vitamins. In this study, A172 cells were used within 30 passages.