Acta Physiologica 2011; Volume 203, Supplement 686
Joint Congress of FEPS and Turkish Society of Physiological Sciences
INDUCTION OF AIRWAY SMOOTH MUSCLE PROLIFERATION BY TGF AND BFGF: THE EFFECT OF SEX HORMONES
Abstract number: PC043
Hatziefthimiou1 Apostolia, Stamatiou1 Rodopi, Paraskeva1 Efrosini, Salatai1 Anta, Gourgoulianis2 Konstantinos, Adam Molyvdas1 Paschalis
1Department of Physiology, Medical School, University of Thessaly, Greece
2Department of Respiratory Medicine, Medical School, University of Thessaly,Greece
Airway wall remodeling, a major characteristic of chronic airway diseases, such as asthma, is believed to contribute to the disease pathogenesis. It is manifested, among others, by the hypertrophy of airway smooth muscle cells (ASMC), caused by the accumulation of inflammatory mediators, including growth factors and cytokines. We have previously shown that 24h exposure of rabbit tracheal ASMC to the genetic hormones, testosterone and 17b-estradiol, caused a transient induction of cell proliferation. The purpose of this study was to examine the effect of growth factors TGF and bFGF alone or combined with genetic hormones, in ASMC proliferation.
Serum starved rabbit tracheal ASMCs were treated with TGF or bFGF and the proliferation was estimated using the Cell Titer 96® AQueous One Solution Assay (Promega) and the methyl-[3H]thymidine incorporation method. The involvement of the PI3K and the MAPK signaling pathways was studied using the inhibitors LY 294002 and PD 89005 respectively and Western blot analysis in total protein cell extracts.
TGF and bFGF activate the p42/42, p38 MAPK and/or the PI3K signaling pathways, increase DNA synthesis and cell number, after 48h of incubation. The co-incubation of ASMCs for 48h with TGF or bFGF and hormones show that testosterone does not change the effect of either growth factor on ASMC proliferation while 17b-estradiol abolished the mitogenic effect of TGF but not of bFGF.
Growth factors, TGF and bFGF induce ASMC proliferation via MAPK and PI3K pathways. Only the mitogenic effect of TGF is affected by 17b-estradiol.
To cite this abstract, please use the following information:
Acta Physiologica 2011; Volume 203, Supplement 686 :PC043