Heme oxygenase-1 in cholecystokinin-octapeptipe attenuated injury of pulmonary artery smooth muscle cells induced by lipopolysaccharide and its signal transduction mechanism.
OBJECTIVE
To study the effect of cholecystokinin-octapeptide (CCK-8) on lipopolysaccharide (LPS) -induced pulmonary artery smooth muscle cell (PASMCs) injury and the role of heme oxygenase-1 (HO-1), and to explore the regulation mechanism of c-Jun N-terminal kinase (JNK) and activator protein-1 (AP-1) signal transduction pathway in inducing HO-1 expression further.


METHODS
Cultured PASMCs were randomly divided into 4 or 6 groups: normal culture group, LPS (10 mg/L), CCK-8 (10(-6) mol/L) plus LPS (10 mg/L) group, CCK-8 (10(-6) mol/L) group, zinc protoporphyrin 9 (ZnPPIX) (10(-6) mol/L) plus LPS (10 mg/L) group, CCK-8 (10(-6) mol/L) plus ZnPPIX and LPS (10 mg/L) group. Seven hours after LPS administration, ultrastructural changes and content of malondialdehyde (MDA) of PASMCs in each group were investigated by electron microscopy and biochemical assay respectively. HO-1 mRNA and protein of PASMCs in the former 4 groups were examined by reverse transcriptase polymerase chain reaction (RT-PCR) and immunocytochemistry staining. Changes of c-fos expression and activation of JNK of PASMCs in the former 4 groups were detected with immunocytochemistry staining and Western blot 30 min after LPS administration.


RESULTS
The injuries of PASMCs and the increases of MDA content induced by LPS were alleviated and significantly reduced by CCK-8 (P<0.05). The specific HO-1 inhibitor- ZnPPIX could worsen LPS-induced injuries and weaken the protective effect of CCK-8. The expressions of c-fos, p-JNK protein and HO-1 mRNA and protein were all slightly increased in LPS group, and significantly enhanced by CCK-8 further (P<0.05).


CONCLUSIONS
HO-1 may be a key factor in CCK-8 attenuated injuries of PASMCs induced by LPS, and HO-1 expression may be related to the activation of JNK and activator protein (AP-1).
Huang
Xin-Li
XL
Department of Pathophysiology, Hebei Medical University, Shijiazhuang 050017, Hebei province, China.
Ling
Yi-Ling
YL
Ling
Yi-Qun
YQ
Zhou
Jun-Lin
JL
Liu
Yan
Y
Wang
Qiu-Hong
QH
D000818:Animals; D015153:Blotting, Western; D002478:Cells, Cultured; D006419:Heme Oxygenase (Decyclizing) / Q000235:genetics / Q000378:metabolism*; D051547:Heme Oxygenase-1; D048031:JNK Mitogen-Activated Protein Kinases; D008070:Lipopolysaccharides / Q000494:pharmacology; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D008854:Microscopy, Electron; D008928:Mitochondria / Q000648:ultrastructure; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000187:drug effects / Q000201:enzymology*; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism; D011651:Pulmonary Artery / Q000166:cytology*; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000187:drug effects* / Q000502:physiology; D012844:Sincalide / Q000494:pharmacology*
D008070:Lipopolysaccharides; D016760:Proto-Oncogene Proteins c-fos; D012333:RNA, Messenger; D008315:Malondialdehyde; D006419:Heme Oxygenase (Decyclizing); D051547:Heme Oxygenase-1; D048031:JNK Mitogen-Activated Protein Kinases; D020928:Mitogen-Activated Protein Kinases; D012844:Sincalide