Identification of a novel inhibitor of LPS-induced TNF-alpha production with antiproliferative activity in monocyte/macrophages.
An isoquinoline derivative, 5-methyl-7,8-dimethoxy-1-phenylpyrazolo[5,4-c]isoquinoline (compound 1), was identified as a novel inhibitor of LPS-induced TNF-alpha production by cell-based screening. Compound 1 suppressed LPS-induced TNF-alpha production in RAW264.7 cells and murine peritoneal macrophages in a dose-dependent manner similar to SB203580, known as a specific inhibitor of p38 MAPK. It also inhibited an LPS-induced increase in serum TNF-alpha in a mouse endotoxic shock model with an ED(50) of approximately 10 mg/kg. Compound 1 had little effect on the incorporation of [3H]-leucine into the cells, while it suppressed LPS-induced TNF-alpha mRNA levels in RAW264.7 cells. The results indicate that suppression of TNF-alpha production was not a result of nonspecific inhibition of de novo translation but was based on the decreased TNF-alpha mRNA levels. The in vitro kinase assay revealed that compound 1 did not strongly inhibit p38 MAPK activity, its potency being much lower than that of SB203580, suggesting that the TNF-alpha-suppressive action of compound 1 cannot be attributed to the inhibition of p38 MAPK. Furthermore, in contrast to SB203580, it significantly inhibited the growth of RAW264.7 and THP-1 cells in a cytostatic manner. Compound 1 is likely to have antiinflammatory and antiproliferative effects by acting on some molecule other than p38 MAPK that contributes to both LPS-induced TNF-alpha production and the cell growth of monocyte/macrophages.
Suntory Biomedical Research Limited, 1-1-1 Wakayamadai, Shimamoto-cho, Mishima-gun, Osaka, 618-8503, Japan.
A
A
Nagahira
K
K
Nagahira
H
H
Murafuji
K
K
Abe
K
K
Magota
M
M
Matsui
S
S
Oikawa
D051698:Activating Transcription Factor 2; D000818:Animals; D002452:Cell Count; D002455:Cell Division / Q000187:drug effects*; D002460:Cell Line; D017362:Cyclic AMP Response Element-Binding Protein / Q000187:drug effects / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects; D007093:Imidazoles / Q000494:pharmacology; D007546:Isoquinolines / Q000737:chemistry / Q000494:pharmacology*; D007930:Leucine / Q000187:drug effects / Q000378:metabolism; D008070:Lipopolysaccharides / Q000494:pharmacology*; D017737:Macrophages, Peritoneal / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D008809:Mice, Inbred C3H; D020928:Mitogen-Activated Protein Kinases / Q000187:drug effects / Q000378:metabolism; D009000:Monocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D011725:Pyridines / Q000494:pharmacology; D012333:RNA, Messenger / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D013997:Time Factors; D014157:Transcription Factors / Q000187:drug effects / Q000378:metabolism; D014316:Tritium; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis / Q000187:drug effects* / Q000235:genetics; D048051:p38 Mitogen-Activated Protein Kinases
C423984:5-methyl-7,8-dimethoxy-1-phenylpyrazolo(5,4-c)isoquinoline; D051698:Activating Transcription Factor 2; D017362:Cyclic AMP Response Element-Binding Protein; D004791:Enzyme Inhibitors; D007093:Imidazoles; D007546:Isoquinolines; D008070:Lipopolysaccharides; D011725:Pyridines; D012333:RNA, Messenger; D014157:Transcription Factors; D014409:Tumor Necrosis Factor-alpha; D014316:Tritium; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D007930:Leucine; C039109:isoquinoline; C093642:SB 203580