Effects of lipopolysaccharide on actin reorganization and actin pools in endothelial cells.
OBJECTIVE
To investigate the dose and time-dependent effects of lipopolysaccharide (LPS) on cytoskeletal F-acitn and G-actin reorganizations by visualizing their distribution and measuring their contents in human umbilical vein endothelial cell line ECV-304.


METHODS
F-actin was labeled with rhodamine-phalloidin and G-actin with deoxyribonuclease I (DNase I)conjugated with fluorescein isothiocyanate (FITC). Contents of cytoskeletal proteins were obtained by flow cytometry.


RESULTS
F-actin was mainly distributed peripherally in endothelial cells under normal conditions. LPS stimulation caused the formation of stress fibers and filopodia. G-actin was normally seen in perinuclear and nuclear areas in control ECV-304 cells. Under LPS stimulation, G-actin dots appeared in the cytoplasmic region. The actin disorganization was accompanied by the time- and dose- dependent decrease in F-actin pool and increase in G-actin pool.


CONCLUSIONS
LPS can induce characteristic morphological alterations of actin cytoskeleton and formation of intercellular gap in endothelial cells, accompanied by changes in F-actin and G-actin pools.
Huang
Qiao-bing
QB
Department of Pathophysiology, First Military Medical University, Guangzhou 510515, China. bing@fimmu.com
Song
Li
L
Zhao
Ke-sen
KS
Chen
Bo
B
Huang
Xu-liang
XL
D000199:Actins / Q000187:drug effects*; D000704:Analysis of Variance; D002478:Cells, Cultured; D003850:Deoxyribonuclease I; D004305:Dose-Response Relationship, Drug; D042783:Endothelial Cells / Q000737:chemistry*; D004926:Escherichia coli; D016650:Fluorescein-5-isothiocyanate; D005456:Fluorescent Dyes; D006801:Humans; D008070:Lipopolysaccharides / Q000494:pharmacology*; D010590:Phalloidine; D012235:Rhodamines; D014471:Umbilical Veins / Q000166:cytology*
D000199:Actins; D005456:Fluorescent Dyes; D008070:Lipopolysaccharides; D012235:Rhodamines; D010590:Phalloidine; D003850:Deoxyribonuclease I; D016650:Fluorescein-5-isothiocyanate