title: Increase in production of hepatocyte growth factor by human embryonic lung fibroblasts in the process of aging in culture.
abstract: It was determined whether human hepatocyte growth factor (hHGF)-producing ability would change in the human embryonic lung fibroblast cell strains (MRC-5 and IMR-90) until the cells senesced in culture. The effects of phorbol 12-myristate 13-acetate (PMA), dexamethasone, and transforming growth factor-beta 1 (TGF-beta 1) on hHGF production were also studied in these cell strains. For stimulation of DNA synthesis of adult rat hepatocytes in primary culture, hHGF secreted by MRC-5 cells at 39.9 and 69.8 population doubling levels (PDLs) showed almost the same activity as recombinant hHGF. Secretion of hHGF by MRC-5 cells increased about threefold between 37.3 and 67.8 PDLs. IMR-90 cells also showed about a threefold increase in hHGF secretion with increased passage from 37.8 to 66.0 PDL. Both cell strains showed almost the same ratio of hHGF amount in the cell extracts to that secreted into the medium around 40 and 70 PDLs. Northern blot analysis showed that the transcriptional level of the hHGF gene in MRC-5 cells increased about three-fold from 42.0 to 73.6 PDL in culture. These findings indicated that hHGF production increased in both cell strains with aging in culture. Production of hHGF in both cell strains was remarkably stimulated by treatment with 10 nM PMA. On the other hand, hHGF production in both cell strains was slightly suppressed by treatment with 1 microM dexamethasone. TGF-beta at a concentration of 5 ng/ml prominently inhibited hHGF production in both cell strains. The response of both cell strains to these regulators for hHGF production was almost the same around 40 and 70 PDLs in culture.
authors.affiliation: Department of Cell Biology, Okayama University Medical School, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Miyazaki
authors.forename: E
authors.initials: E
authors.lastname: Gohda
authors.forename: K
authors.initials: K
authors.lastname: Mihara
authors.forename: S
authors.initials: S
authors.lastname: Tsuboi
authors.forename: K
authors.initials: K
authors.lastname: Kaji
authors.forename: I
authors.initials: I
authors.lastname: Yamamoto
authors.forename: M
authors.initials: M
authors.lastname: Namba
mesh_terms: D000818:Animals; D001681:Biological Assay; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D016922:Cellular Senescence / Q000502:physiology*; D017077:Culture Media, Conditioned; D003907:Dexamethasone / Q000494:pharmacology; D004622:Embryo, Mammalian; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism*; D017228:Hepatocyte Growth Factor / Q000096:biosynthesis* / Q000235:genetics; D006801:Humans; D008099:Liver / Q000166:cytology / Q000187:drug effects; D008168:Lung / Q000166:cytology / Q000378:metabolism*; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D016212:Transforming Growth Factor beta / Q000494:pharmacology
chemical_list: D017077:Culture Media, Conditioned; D012333:RNA, Messenger; D016212:Transforming Growth Factor beta; D017228:Hepatocyte Growth Factor; D003907:Dexamethasone; D013755:Tetradecanoylphorbol Acetate