Up-regulation interleukin-6 and interleukin-8 by activated protein C in lipopolysaccharide-treated human umbilical vein endothelial cells.
OBJECTIVE
To investigate the effect of activated protein C (APC) on inflammatory responses in human umbilical vein endothelial cells (HUVEC) stimulated with lipopolysaccharide (LPS).


METHODS
The second passage of collagenase digested HUVEC was divided into the following groups: serum free medium control group (SFM control), phosphate buffer solution control group (PBS control), LPS group with final concentration of 1 microg/ml (LPS group), APC group with final concentration of 7 microg/ml, Pre-APC group (APC pretreatment for 30 min prior to LPS challenge), and Post-APC group (APC administration 30 min after LPS challenge). Supernatant was harvested at 0, 4, 8, 12 and 24 h after LPS challenge. Interleukin-6 (IL-6) and Interleukin-8 (IL-8) levels were analyzed with ELISA. Cells were harvested at 24 h after LPS challenge, and total RNA was extracted. Messenger RNA levels for IL-6 and IL-8 were semi-quantitatively determined by RT-PCR.


RESULTS
Compared with control group, IL-6 and IL-8 levels steadily increased 4 to 24 h after LPS stimulation. APC treatment could increase LPS-induced IL-6 and IL-8 production. The mRNA levels of IL-6 and IL-8 exhibited a similar change.


CONCLUSIONS
APC can further increase the level of IL-6 and IL-8 induced by LPS. The effect of these elevated cytokines is still under investigation.
Li
Yi
Y
Department of Critical Care Medicine, Peking Union Medical College Hospital, Chinese Medical Academy, Beijing 100730, China. billliyi@yahoo.com
Du
Bin
B
Pan
Jia-qi
JQ
Chen
De-chang
DC
Liu
Da-wei
DW
D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D042783:Endothelial Cells / Q000187:drug effects* / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D015870:Gene Expression; D006801:Humans; D015850:Interleukin-6 / Q000378:metabolism*; D016209:Interleukin-8 / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000494:pharmacology*; D011486:Protein C / Q000502:physiology*; D018046:Protein C Inhibitor / Q000494:pharmacology*; D012333:RNA, Messenger / Q000187:drug effects / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012680:Sensitivity and Specificity; D013997:Time Factors; D015854:Up-Regulation
D015850:Interleukin-6; D016209:Interleukin-8; D008070:Lipopolysaccharides; D011486:Protein C; D018046:Protein C Inhibitor; D012333:RNA, Messenger