[Adenovirus-mediated protein-kinase-GIalpha suppresses the hypoxia-induced proliferation and phenotype-switching of pulmonary arterial smooth muscle cell].
OBJECTIVE
To observe the proliferation and phenotype-switching of pulmonary arterial smooth muscle cell (PASMC) induced by hypoxia and interfered by Ad-PKGIα. And to investigate the potential regulative role of PKGIα gene in the molecule mechanism of hypoxia pulmonary vessel remodeling (HPVR).


METHODS
To establish the pure PASMC cultured by tissue-sticking methods. Semi-quantitative reverse transcription and polymerase chain reaction (RT-PCR) and Western blot were used to examine the PKGIα mRNA and protein expression after PASMC were transfected by Ad-PKG. The mRNA and protein expressive change of smooth muscle alpha actin (SM-alpha-actin) determined the degree of cell phenotype-switching. The changes of PASMC proliferation were determined by flow cytometry and ³H-TdR incorporated way.


RESULTS
Ad-PKGIα could transfect into PASMC and highly express. Hypoxia down-regulated the expression of SM-alpha-actin protein (44.25 ± 5.34 in normoxia, 32.18 ± 4.19 in 12 h hypoxia condition, 21.90 ± 2.44 in 24 h hypoxia condition, P < 0.05), that could be blocked by the transfection of Ad-PKGIα. Hypoxia could push PASMC mitosis and proliferating (³H-TdR incorporated way: 7570 ± 371 in normoxia, 12,020 ± 831 in 12 h hypoxia condition, 14,924 ± 1491 in 24 h hypoxia condition, P < 0.05), that could be blocked by the transfection of Ad-PKGIα, too.


CONCLUSIONS
The results suggested that PKGIα signaling pathway might play an important role in the molecule mechanism of HPVR. And PKGIα gene might be a target point of gene therapy.
Yi
Bin
B
Institute of Respiratory Diseases, Xinqiao Hospital, Third Military Medical University, Chongqing 400038, China.
Lu
Jun-yu
JY
Bai
Li
L
Wang
Guan-song
GS
Qian
Gui-sheng
GS
D000256:Adenoviridae / Q000235:genetics; D015687:Cell Hypoxia / Q000235:genetics; D049109:Cell Proliferation; D002478:Cells, Cultured; D062965:Cyclic GMP-Dependent Protein Kinase Type I; D017869:Cyclic GMP-Dependent Protein Kinases / Q000235:genetics*; D006801:Humans; D032389:Myocytes, Smooth Muscle / Q000378:metabolism*; D011651:Pulmonary Artery / Q000166:cytology*; D012333:RNA, Messenger / Q000235:genetics; D015398:Signal Transduction
D012333:RNA, Messenger; D062965:Cyclic GMP-Dependent Protein Kinase Type I; D017869:Cyclic GMP-Dependent Protein Kinases; C569718:PRKG1 protein, human