Human immunodeficiency virus type 1 envelope glycoprotein 120 induces cyclooxygenase-2 expression in neuroblastoma cells through a nuclear factor-jB and activating protein-1 mediated mechanism Susana A ´ lvarez,* M a Jesu ´ s Serramı ´a,* Manuel Fresno and M a A ´ ngeles Mun ˜oz-Ferna ´ndez* *Laboratory Inmuno-Biologı ´a Molecular, Hospital General Universitario Gregorio Maran ˜o ´n, Madrid, Spain  Centro de Biologı ´a Molecular, Consejo Superior de Investigaciones Cientı ´ficas – Universidad Auto ´noma de Madrid, Cantoblanco, Madrid, Spain Abstract Induction of cyclooxygenase-2 (COX-2) in the brain of people infected with human immunodeficiency virus type 1 (HIV-1) has been proposed as a cause of cognitive impairment in AIDS dementia. Here, we have analyzed the molecular mechanism by which its induction takes place in neurobla- stoma cells. The HIV-1 envelope protein gp120 was able to induce COX-2 mRNA and protein in several human neuro- blastoma cell lines, which express CXCR4 and CCR5 but not CD4. Moreover, gp120 induces COX-2 promoter transcription. Sequential deletions of the promoter show that deletion of a distal nuclear factor-jB (NF-jB) site abrogated gp120- dependent transcription. More importantly, overexpression of NF-jB inhibitory subunit, IjBa, completely abrogated gp120- induced COX-2 activity. However, transfection of p65/relA NF-jB was not enough to induce COX-2 transcription, sug- gesting that NF-jB was necessary but not sufficient to control COX-2 transcription induced by gp120. In addition to NF-jB, activating protein-1 (AP-1) but not nuclear factor of activated T cells (NFAT)-dependent transcription was induced by gp120. Transfection of a dominant negative mutant c-Jun protein, TAM-67, efficiently blocked the induction of COX-2 promoter by gp120, confirming AP-1 requirement. Moreover, gp120 rapidly activates the c-Jun amino-terminal kinase (JNK) and p38 mitogen-activated protein kinase phosphorylation. The importance of NF-jB and AP-1 in COX-2 promoter and protein induction was corroborated by using pharmacological NF-jB, p38 and JNK inhibitors. Keywords: cyclooxygenase-2, human immunodeficiency virus type 1, neural cells. J. Neurochem. (2005) 94, 850–861. Human immunodeficiency virus (HIV)-associated dementia (HAD) results in impaired cognitive function, psychomotor slowing and altered behavior. It has been estimated that 20–30% of HIV-infected individuals eventually develop HAD, although highly active antiretroviral therapy (HAART) might reduce its incidence and can arrest or even reverse the process of dementia, at least temporarily, in some infected patients (McArthur et al. 2003). Neurons are not generally infected by HIV-1, suggesting that neuronal damage is likely to be induced by soluble factors including viral proteins, proinflammatory cytokines or chemokines released by HIV- 1-infected macrophages/microglial cells (Munoz-Fernandez and Fresno 1998; Gabuzda and Wang 2000). The HIV-1 envelope glycoprotein gp120 has been pro- posed as the main etiologic agent responsible for neuronal Received September 21, 2004; revised manuscript received March 20, 2005; accepted April 11, 2005. Address correspondence and reprint requests to M a A ´ ngeles Mun ˜oz Ferna ´ndez, Laboratory Inmuno-Biologı ´a Molecular, Hospital General Universitario Gregorio Maran ˜o ´n, 28007, Madrid, Spain. E-mail: mmunoz@cbm.uam.es Abbreviations used: AP-1, activating protein-1; COX-2, cyclooxyge- nase-2; CRE, cyclic AMP-response element; GADPH, Glyceraldehyde- 3-phosphate dehydrogenase; gp120, glycoprotein 120; HAART, highly active antiretroviral therapy; HAD, HIV-associated dementia; HIV-1, human immunodeficiency virus type 1; IjBa, inhibitory proteins of NF-jB; IL, interleukin; JNK, c-Jun amino-terminal kinase; MAPK, mitogen-activated protein kinase; NB cells, neuroblastoma cells; NFAT, nuclear factor of activated T cells; NF-jB, nuclear factor-jB; PDTC, pyrrolidine dithiocarbamate; RANTES, regulated on activation normal T cell expressed and secreted; RT–PCR, reverse transcription polymerase chain reaction; SDF-1a, stromal cell-derived factor 1a; TK, thymidine kinase; TNF-a, tumor necrosis factor-a. Journal of Neurochemistry , 2005, 94, 850–861 doi:10.1111/j.1471-4159.2005.03267.x 850 Ó 2005 International Society for Neurochemistry, J. Neurochem. (2005) 94, 850–861