title: Role of phospholipase C and tyrosine kinase systems in growth response of human airway smooth muscle cells.
abstract: The primary culture of confluent human airway smooth muscle (ASM) cells were exposed up to 5 days to human recombinant interleukin (IL)-1 beta in the presence of indomethacin and 1% fetal bovine serum. The proliferation was assessed by a [3H]thymidine incorporation and direct cell count. We found that IL-1 beta significantly increased thymidine incorporation into and cell count of ASM cells in a concentration-dependent manner. Pretreatment of cells with specific polyclonal antibodies against platelet-derived growth factor (PDGF-BB homodimer) completely inhibited the IL-1 beta-induced increase in thymidine incorporation. The PDGF-BB, at the concentrations of 1.5 and 2.5 ng/ml, stimulated the proliferation of ASM cells. The proliferation action of IL-1 beta was potentiated when PDGF-BB was added into the medium in combination with IL-1 beta. Pretreatment of cells with genistein (0.37 microM), a specific tyrosine kinase inhibitor, attenuated the proliferative effect of IL-1 beta and PDGF-BB. To clarify whether these growth stimuli (IL-1 beta and PDGF-BB) activated phospholipase C (PLC), we examined the formation of phosphatidylinositols. We observed that both agents significantly increased phosphoinositide turnover. In contrast, genistein pretreatment (0.37 microM) prevented formation of inositol 1,4,5-trisphosphate (IP3), as induced by IL-1 beta and/or PDGF-BB. This study demonstrates that both IL-1 beta and PDGF-BB could induce proliferation of ASM cells through the activation of tyrosine kinase and PLC, which in turn stimulate the formation of IP3, a second messenger molecule.
authors.affiliation: John B. Pierce Laboratory, New Haven, Connecticut 06519, USA.
authors.forename: S
authors.initials: S
authors.lastname: De
authors.forename: E T
authors.initials: ET
authors.lastname: Zelazny
authors.forename: J F
authors.initials: JF
authors.lastname: Souhrada
authors.forename: M
authors.initials: M
authors.lastname: Souhrada
mesh_terms: D000077214:Becaplermin; D001980:Bronchi / Q000166:cytology*; D002455:Cell Division / Q000187:drug effects / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000494:pharmacology; D019833:Genistein; D006801:Humans; D015544:Inositol 1,4,5-Trisphosphate / Q000096:biosynthesis; D007375:Interleukin-1 / Q000494:pharmacology; D007529:Isoflavones / Q000494:pharmacology; D009130:Muscle, Smooth / Q000166:cytology*; D010982:Platelet-Derived Growth Factor / Q000494:pharmacology; D011505:Protein-Tyrosine Kinases / Q000378:metabolism*; D020574:Proto-Oncogene Proteins c-sis; D011994:Recombinant Proteins; D013936:Thymidine / Q000378:metabolism; D010738:Type C Phospholipases / Q000378:metabolism*
chemical_list: D004791:Enzyme Inhibitors; D007375:Interleukin-1; D007529:Isoflavones; D010982:Platelet-Derived Growth Factor; D020574:Proto-Oncogene Proteins c-sis; D011994:Recombinant Proteins; D000077214:Becaplermin; D015544:Inositol 1,4,5-Trisphosphate; D019833:Genistein; D011505:Protein-Tyrosine Kinases; D010738:Type C Phospholipases; D013936:Thymidine