Up-regulation of cyclin D1 expression in asthma serum-sensitized human airway smooth muscle promotes proliferation via protein kinase C alpha.
Abnormal hypertrophy and hyperplasia of airway smooth muscle cells play an important role in airway remodeling in chronic asthma. The authors' previous studies have indicated that protein kinase C alpha (PKC alpha) is involved in the proliferation of passively sensitized human airway smooth muscle cells (HASMCs). However, the underlying mechanisms remain unknown. Here, the authors examined the possible role of the alpha isoform of PKC in the control of cyclin D1 expression, using HASMCs passively sensitized on human atopic asthmatic serum as a model system. Cultured HASMCs were passively sensitized with serum from atopic asthmatic patients. Cell proliferation was measured by [(3)H]thymidine incorporation and an MTT assay. Cell cycle status was analyzed by flow cytometry. The mRNA and protein expression profiles of cyclin D1 were measured by reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blotting, respectively. Furthermore, the authors assessed the role of cyclin D1 in PKC alpha-induced HASMC proliferation by transfection with a recombinant cyclin D1 antisense construct. The activation of PKC alpha with phorbol myristate acetate (PMA), a PKC activator, up-regulated cyclin D1 expression and increased the proliferation of passively sensitized HASMCs. This effect was significantly decreased by specific inhibition of PKC alpha with Go6976. In addition, the authors showed that transfection with antisense cyclin D1 abolished PMA-induced G1/S progression and HASMC proliferation. These results demonstrate that PKC alpha promotes the proliferation of HASMCs sensitized with atopic asthmatic serum via up-regulation of cyclin D1 expression.
Du
Chun-Ling
CL
Department of Respiratory Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
Xu
Yong-Jian
YJ
Liu
Xian-Sheng
XS
Xie
Jun-Gang
JG
Xie
Min
M
Zhang
Zhen-Xiang
ZX
Zhang
Jian
J
Qiao
Li-Fen
LF
D000328:Adult; D001249:Asthma / Q000201:enzymology* / Q000473:pathology; D001980:Bronchi / Q000201:enzymology* / Q000473:pathology; D002227:Carbazoles; D049109:Cell Proliferation; D002478:Cells, Cultured; D019938:Cyclin D1 / Q000378:metabolism*; D005260:Female; D006801:Humans; D007527:Isoenzymes; D008297:Male; D008875:Middle Aged; D032389:Myocytes, Smooth Muscle / Q000502:physiology*; D051571:Protein Kinase C-alpha / Q000378:metabolism*; D044967:Serum; D013755:Tetradecanoylphorbol Acetate; D015854:Up-Regulation; D055815:Young Adult
C530104:CCND1 protein, human; D002227:Carbazoles; D007527:Isoenzymes; C081021:Go 6976; D019938:Cyclin D1; D051571:Protein Kinase C-alpha; D013755:Tetradecanoylphorbol Acetate