K. Mochida-nishimura et al., Differential activation of MAP kinase signaling pathways and nuclear factor-kappa B in bronchoalveolar cells of smelters and nonsmokers, MOL MED, 7(3), 2001, pp. 177-185
Citations number
54
Categorie Soggetti
Research/Laboratory Medicine & Medical Tecnology","Medical Research General Topics
Background: Prolonged exposure of alveolar macrophages (AM) to components o
f tobacco smoke, including nicotine and aromatic hydrocarbons, may lead to
alterations in activation of cellular signaling pathways. In this study, we
compared the spontaneous and LPS-stimulated activation of MAP kinases and
NF-kappaB in bronchoalveolar cells (BAC) from smokers and nonsmokers.
Material and Methods: BAC, which were predominantly comprised of AM, were o
btained by bronchoalveolar lavage of healthy volunteering adult smelters an
d nonsmokers. Nuclear and cytoplasmic extracts were prepared from cell lysa
tes. Activation of NF-kappaB was assessed by electrophoretic mobility shift
assay. Degradation of the inhibitor of NF-kappaB (I kappaB) and total MAP
kinases were assessed by Western blot analysis. Activation of MAP kinases,
ERK, SAPK/JNK, and p38 were assessed by immunoprecipitation of cell lysates
and kinase assays.
Results: LPS induced the activation of NF-kappaB in a dose-dependent manner
, but BAC from smokers were approximately 10 times more sensitive, and show
ed faster kinetics of activation of NF-kappaB than BAC from nonsmokers. All
three classes of MAP kinase-ERK, SAPK, and p38-were simultaneously activat
ed by LPS in BAC from smokers and nonsmokers. However, the individual MAP k
inases exhibited differential kinetics of activation. Activation of p38 was
more rapid in BAC from smokers, whereas the activation of ERK and SAPK was
similar in both groups.
Conclusion: The differences in activation of NF-kappaB and MAP kinases in B
AC from Smokers and nonsmokers may relate to the differences in their micro
environment in situ as affected by chronic exposure to cigarette smoke. The
se differences may contribute to the increased susceptibility of smokers to
infections, including infection with HN-I, and lung disease.