Proteomic analysis of the effect of iptakalim on human pulmonary arterial smooth muscle cell proliferation.
OBJECTIVE
To investigate the anti-proliferative effect of iptakalim (Ipt), a newly selective K(ATP) channel opener, in endothelin-1 (ET-1)-induced human pulmonary arterial smooth muscle cells (PASMCs) using proteomic analysis.


METHODS
Human PASMCs were incubated with ET-1 (10(-8) mol/L) and ET-1 (10(-8) mol/L) plus iptaklim (10(-5) mol/L) for 24 h. Analysis via 2-DE gel electrophoresis and MALDI-TOF-MS was employed to display the different protein profiles of whole-cell protein from cultures of control, ET-1 treatment alone, and treatment with ET-1 and iptaklim combined. Real time RT-PCR and Western blot analysis were used to confirm the proteomic analysis.


RESULTS
When iptakalim inhibited the proliferative effect of ET-1 in human PASMCs by opening the K(ATP) channels, the expression of different groups of cellular proteins was changed, including cytoskeleton-associated proteins, plasma membrane proteins and receptors, chaperone proteins, ion transport-associated proteins, and glycolytic and metabolism-associated proteins. We found that iptakalim could inhibit the proliferation of human PASMCs partly by affecting the expression of Hsp60, vimentin, nucleoporin P54 (NUP54) and Bcl-X(L) by opening the K(ATP) channel.


CONCLUSIONS
The data suggest that a wide range of signaling pathways may be involved in abolishing ET-1-induced proliferation of human PASMCs following iptakalim treatment.
Yang
Ming-Xia
MX
Department of Respiratory Medicine, The First Affiliated Hospital, Nanjing Medical University, Nanjing, China.
Liu
Zheng-Xia
ZX
Zhang
Shu
S
Jing
Yu
Y
Zhang
Shi-Jiang
SJ
Xie
Wei-Ping
WP
Ma
Lei
L
Zhu
Chang-Liang
CL
Wang
Hong
H
D049109:Cell Proliferation / Q000187:drug effects*; D048430:Cell Shape; D002478:Cells, Cultured; D019332:Endothelin-1 / Q000378:metabolism; D006801:Humans; D008969:Molecular Sequence Data; D032389:Myocytes, Smooth Muscle / Q000166:cytology / Q000187:drug effects* / Q000502:physiology*; D011437:Propylamines / Q000494:pharmacology*; D011651:Pulmonary Artery / Q000166:cytology*; D015398:Signal Transduction / Q000502:physiology
D019332:Endothelin-1; C502260:N-(1-methylethyl)-1,1,2-trimethylpropylamine; D011437:Propylamines