title: Mycoplasma genitalium-derived lipid-associated membrane proteins induce activation of MAPKs, NF-kappaB and AP-1 in THP-1 cells.
abstract: Mycoplasma genitalium lipid-associated membrane proteins (LAMPg) can induce human monocytic cell line THP-1 to produce proinflammatory cytokines, including tumor necrosis factor-alpha (TNF-alpha), IL-1beta and IL-6, as demonstrated by an enzyme-linked immunosorbent assay and reverse transcription-PCR (RT-PCR). This study also investigated the signaling transduction pathways involved in the production of these cytokines. THP-1 cells were stimulated with LAMPg and then examined for the activation of MAPKs, such as SAPK/JNK, p38, extracellular signal-regulated kinase (ERK)1/2 and NF-kappaB and AP-1. Western blot clearly showed that stress-activated protein kinase (SAPK)/c-Jun-N-terminal kinase (JNK), p38 and ERK1/2 were activated in response to LAMPg, peaking at 30 min. SAPK/JNK-specific inhibitor SP600125 slightly suppressed IL-6 production although no evident effects were obtained for TNF-alpha and IL-1beta; ERK1/2 inhibitor PD98059 blocked both TNF-alpha and IL-1beta, but not IL-6 production. However, p38 inhibitor SB203580 abrogated TNF-alpha, IL-1beta and IL-6 production. The DNA-binding activity of NF-kappaB and AP-1 was also assessed by an electrophoretic mobility gel shift assay, and an NF-kappaB specific inhibitor, pyrrolidine dithiocarbamate, profoundly inhibited the synthesis and production of the proinflammatory cytokines. Based on these results, this study concludes that MAPKs, NF-kappaB and AP-1 may play important roles in the genital tract inflammatory reaction after mycoplasma infection.
authors.affiliation: Pathogenic Biology Institute, University of South China, Hengyang, China.
authors.forename: Xiaoxing
authors.initials: X
authors.lastname: You
authors.forename: Yimou
authors.initials: Y
authors.lastname: Wu
authors.forename: Yanhua
authors.initials: Y
authors.lastname: Zeng
authors.forename: Zhongliang
authors.initials: Z
authors.lastname: Deng
authors.forename: Hong
authors.initials: H
authors.lastname: Qiu
authors.forename: Minjun
authors.initials: M
authors.lastname: Yu
mesh_terms: D000873:Anthracenes / Q000494:pharmacology; D001426:Bacterial Proteins / Q000276:immunology*; D015153:Blotting, Western; D004247:DNA / Q000378:metabolism; D024202:Electrophoretic Mobility Shift Assay; D004791:Enzyme Inhibitors; D005419:Flavonoids / Q000494:pharmacology; D006801:Humans; D007093:Imidazoles / Q000494:pharmacology; D053583:Interleukin-1beta / Q000096:biosynthesis; D015850:Interleukin-6 / Q000096:biosynthesis; D008565:Membrane Proteins / Q000276:immunology*; D020929:Mitogen-Activated Protein Kinase Kinases / Q000037:antagonists & inhibitors / Q000096:biosynthesis*; D009000:Monocytes / Q000276:immunology / Q000382:microbiology*; D045704:Mycoplasma genitalium / Q000276:immunology*; D016328:NF-kappa B / Q000037:antagonists & inhibitors / Q000378:metabolism*; D011485:Protein Binding; D011725:Pyridines / Q000494:pharmacology; D011759:Pyrrolidines / Q000494:pharmacology; D013859:Thiocarbamates / Q000494:pharmacology; D013997:Time Factors; D018808:Transcription Factor AP-1 / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis
chemical_list: D000873:Anthracenes; D001426:Bacterial Proteins; D004791:Enzyme Inhibitors; D005419:Flavonoids; D007093:Imidazoles; D053583:Interleukin-1beta; D015850:Interleukin-6; D008565:Membrane Proteins; D016328:NF-kappa B; D011725:Pyridines; D011759:Pyrrolidines; D013859:Thiocarbamates; D018808:Transcription Factor AP-1; D014409:Tumor Necrosis Factor-alpha; C432165:pyrazolanthrone; C020972:pyrrolidine dithiocarbamic acid; D004247:DNA; D020929:Mitogen-Activated Protein Kinase Kinases; C093642:SB 203580; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one