title: Expression of the mu opioid receptor in the human immunodeficiency virus type 1 transgenic rat model.
abstract: Opioids, via the mu opioid receptor (MOR), can exacerbate bacterial infections and the immunopathogenesis of human immunodeficiency virus type 1 (HIV-1) infection. Recently, an HIV-1 transgenic (HIV-1Tg) rat model containing circulating HIV-1 gp120 was created. Using real-time reverse transcription-PCR, we found that MOR mRNA levels were significantly higher in the peritoneal macrophages of the HIV-1Tg rat than those in control animals. Lipopolysaccharide, a bacterial endotoxin, induced secretion of the inflammatory cytokines tumor necrosis factor alpha (TNF-alpha), interleukin-beta (IL-beta), and IL-10 in the HIV-1Tg rat and further increased MOR expression. Ex vivo studies showed that MOR expression was up-regulated in the peritoneal macrophages of F344 control rats by exposure to serum from HIV-1Tg rats and that MOR up-regulation was abolished by addition of gp120 antibody to the serum. In human TPA-differentiated HL-60 cells, which are macrophage-like cells, LPS-induced MOR mRNA up-regulation was greater in gp120-pretreated cells than in vehicle-pretreated cells. Our data suggest that in individuals infected with HIV-1, the MOR is up-regulated, possibly by circulating HIV-1 proteins such as gp120, and HIV-1 proteins may play a significant role in modulating the response to bacterial infection in opioid-using HIV-infected individuals. Furthermore, our results demonstrate that the new HIV-1Tg rat model can be a valuable tool with which to study MOR gene expression and its effects in the continuous presence of HIV viral proteins.
authors.affiliation: Department of Biological Sciences, Seton Hall University, 400 South Orange Avenue, South Orange, NJ 07079, USA. changsul@shu.edu
authors.forename: Sulie L
authors.initials: SL
authors.lastname: Chang
authors.forename: Jose A
authors.initials: JA
authors.lastname: Beltran
authors.forename: Shilpa
authors.initials: S
authors.lastname: Swarup
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D015870:Gene Expression; D015699:HIV Envelope Protein gp120 / Q000235:genetics / Q000378:metabolism*; D015658:HIV Infections / Q000235:genetics / Q000276:immunology*; D015497:HIV-1 / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D016753:Interleukin-10 / Q000097:blood; D053583:Interleukin-1beta / Q000097:blood; D008070:Lipopolysaccharides / Q000494:pharmacology; D017737:Macrophages, Peritoneal / Q000276:immunology; D051381:Rats; D017450:Receptors, Opioid, mu / Q000235:genetics / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000097:blood
chemical_list: D015699:HIV Envelope Protein gp120; D053583:Interleukin-1beta; D008070:Lipopolysaccharides; D017450:Receptors, Opioid, mu; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10