[Effect of C5a on expression of thrombomodulin in endothelial cells in vitro].
OBJECTIVE
To investigate the effect of C5a on the expression of thrombomodulin (TM) in human umbilical vein endothelial cells (HUVECs).


METHODS
HUVECs cultured in vitro were stimulated with C5a for 8, 12, 16, 20 hours in a concentration of 200 microg/L, and also with different concentrations of 100, 200, 300 microg/L for 12 hours respectively. The levels of both mRNA and protein expression of TM was detected by real-time polymerase chain reaction (PCR) and Western blotting respectively, and the dose and time dependent effects of C5a on the expression of TM were evaluated.


RESULTS
C5a down-regulated the TM expression at both protein and mRNA level. The down-regulation was time-dependent [(93.11+/- 1.57) x10(-2) , (71.05+/-3.39)x10(-2), (65.48+/-4.28)x10(-2), (62.69+/-4.03)x10(-2)at protein level and (301.71+/-80.40)x10(-6), (38.29+/-20.24)x10(-6), (8.82+/-2.66)x10(-6), (7.05+/-0.80)x10(-6) at mRNA level, all P<0.05] and dose-dependent [(113.25+/-3.97)x10(-2), (80.18+/-2.56)x10(-2), (73.22+/- 4.36)x10(-2) at protein level and (401.77+/-20.46)x10(-6), (31.12+/-3.51)x10(-6), (18.19+/-1.46)x10(-6) at mRNA level , all P<0.05]. When concentration of C5a at 300 microg/L was used to stimulate HUVECs for longer than 12 hours, the lowering of TM at protein level was slowed down obviously. And concentration of C5a at 200 microg/L was used to stimulate HUVECs for 12 hours, the lowering of TM at mRNA level was slowed down obviously.


CONCLUSIONS
C5a can depress the gene expression of TM, and then affect the protein's translation. By this means, C5a can lead to hypercoagulability and inflammatory injuries in sepsis.
Fang
Wei
W
Guangzhou Medical College, Guangzhou 510010, Guangdong, China.
Guo
Zhen-hui
ZH
Zhang
Bao-quan
BQ
Wu
Xiao-feng
XF
Li
Ping
P
Lv
Feng-lin
FL
Su
Lei
L
D002478:Cells, Cultured; D015936:Complement C5a / Q000494:pharmacology*; D042783:Endothelial Cells / Q000187:drug effects / Q000378:metabolism*; D004730:Endothelium, Vascular / Q000166:cytology; D006801:Humans; D012333:RNA, Messenger / Q000235:genetics; D018180:Thrombomodulin / Q000235:genetics / Q000378:metabolism*; D014471:Umbilical Veins / Q000166:cytology
D012333:RNA, Messenger; D018180:Thrombomodulin; D015936:Complement C5a