title: Inhibition of human immunodeficiency virus type 1 replication in latently infected cells by a novel IkappaB kinase inhibitor.
abstract: In human immunodeficiency virus type 1 (HIV-1) latently infected cells, NF-kappaB plays a major role in the transcriptional induction of HIV-1 replication. Hence, downregulation of NF-kappaB activation has long been sought for effective anti-HIV therapy. Tumor necrosis factor alpha (TNF-alpha) stimulates IkappaB kinase (IKK) complex, a critical regulator in the NF-kappaB signaling pathway. A novel IKK inhibitor, ACHP {2-amino-6-[2-(cyclopropylmethoxy)-6-hydroxyphenyl]-4-piperidin-4-yl-nicotinonitrile}, was developed and evaluated as a potent and specific inhibitor for IKK-alpha and IKK-beta. In this study, we examined the ability of this compound to inhibit HIV-1 replication in OM10.1 cells latently infected with HIV. When these cells were pretreated with ACHP, TNF-alpha-induced HIV-1 replication was dramatically inhibited, as measured by the HIV p24 antigen levels in the culture supernatants. Its 50% effective concentration was approximately 0.56 microM, whereas its 50% cytotoxic concentration was about 15 microM. Western blot analysis revealed inhibition of IkappaBalpha phosphorylation, IkappaBalpha degradation, p65 nuclear translocation, and p65 phosphorylation. ACHP was also found to suppress HIV-1 long terminal repeat (LTR)-driven gene expression through the inhibition of NF-kappaB activation. Furthermore, ACHP inhibited TNF-alpha-induced NF-kappaB (p65) recruitment to the HIV-1 LTR, as assessed by chromatin immunoprecipitation assay. These findings suggest that ACHP acts as a potent suppressor of TNF-alpha-induced HIV replication in latently infected cells and that this inhibition is mediated through suppression of IKK activity.
authors.affiliation: Department of Molecular and Cellular Biology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.
authors.forename: Ann Florence B
authors.initials: AF
authors.lastname: Victoriano
authors.forename: Kaori
authors.initials: K
authors.lastname: Asamitsu
authors.forename: Yurina
authors.initials: Y
authors.lastname: Hibi
authors.forename: Kenichi
authors.initials: K
authors.lastname: Imai
authors.forename: Nina G
authors.initials: NG
authors.lastname: Barzaga
authors.forename: Takashi
authors.initials: T
authors.lastname: Okamoto
mesh_terms: D021581:Active Transport, Cell Nucleus / Q000187:drug effects; D019380:Anti-HIV Agents / Q000494:pharmacology*; D002460:Cell Line; D016325:HIV Long Terminal Repeat / Q000187:drug effects; D015497:HIV-1 / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D051550:I-kappa B Kinase / Q000037:antagonists & inhibitors* / Q000378:metabolism / Q000502:physiology; D010766:Phosphorylation; D047428:Protein Kinase Inhibitors / Q000494:pharmacology*; D051996:Transcription Factor RelA / Q000037:antagonists & inhibitors / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology; D017735:Virus Latency; D014779:Virus Replication / Q000187:drug effects*
chemical_list: D019380:Anti-HIV Agents; D047428:Protein Kinase Inhibitors; D051996:Transcription Factor RelA; D014409:Tumor Necrosis Factor-alpha; D051550:I-kappa B Kinase