Endothelin-1 promoted proliferation of vascular smooth muscle cell through pathway of extracellular signal-regulated kinase and cyclin D1.
OBJECTIVE
To investigate whether endothelin-1 (ET-1) can promote human umbilical artery smooth muscle cell (HUASMC) proliferation through pathway of extracellular signal-regulated kinase (ERK) and cyclin D1.


METHODS
The effects of ET-1 and PD98059 on HUASMC were evaluated by MTT assay. The content of DNA was defined by [3H]TdR assay and cell cycle was analyzed by flow cytomerty. Western blot analysis was employed to detect the active phosphorylated state of ERK and the expression of cylin D1.


RESULTS
Firstly, ET-1 (100 nmol/L) stimulated HUASMC proliferation compared with the group without ET-1 (P<0.05) and PD98059 group (P<0.05). PD98059 inhibited the HUASMC proliferation stimulated by ET-1 (P<0.05). Secondly, ET-1 stimulated DNA synthesis of HUASMC compared with the group without ET-1 (P<0.05). Thirdly, ET-1 promoted the cell cycle transition from G0/G1 phase to S phase. G0/G1 phase cell percentage was obviously decreased compared with the group without ET-1 (P<0.05). S phase cell percentage was increased compared with the group without ET-1 (P<0.05). Fourthly, ET-1 increased the phosphorylated level of ERK and the expression of cylin D1, an inhibitor of ERK blocked phosphorylated level of ERK and cyclin D1 expression. ERK phosphorylated level of ET-1 group was evidently increased compared with PD98059 group (P<0.05), Cyclin D1 protein expression also was increased compared with PD98059 group (P<0.05). While nonphosphorylated ERK expression remained unchanged.


CONCLUSIONS
Endothelin-1 promoted vascular smooth muscle cell proliferation through pathway of ERK and cyclin D1.
Zhang
Ying-Min
YM
Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital of Fudan University, Shanghai 200032, China.
Wang
Ke-Qiang
KQ
Zhou
Guo-Min
GM
Zuo
Ji
J
Ge
Jun-Bo
JB
D002453:Cell Cycle / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D019938:Cyclin D1 / Q000378:metabolism*; D004247:DNA / Q000096:biosynthesis; D019332:Endothelin-1 / Q000494:pharmacology*; D005419:Flavonoids / Q000494:pharmacology; D006801:Humans; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism*; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000187:drug effects*; D010766:Phosphorylation / Q000187:drug effects; D015398:Signal Transduction; D014469:Umbilical Arteries / Q000166:cytology
D019332:Endothelin-1; D005419:Flavonoids; D019938:Cyclin D1; D004247:DNA; D019950:Mitogen-Activated Protein Kinase 1; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one