beta-Sitosterol modulation of monocyte-endothelial cell interaction: a comparison to female hormones.
OBJECTIVE
To investigate the effect of beta-sitosterol, 17beta-estradiol and progesterone on oxidized LDL (oxLDL)-stimulated human umbilical venous endothelial cell (HUVEC) expression of intercellular adhesion molecule-1 (ICAM-1), THP-1 monocyte chemotactic activity, migration and adhesion of THP-1 cells co-cultured with HUVECs.


METHODS
ICAM-1 expression was determined by immunofluorescence in HUVEC monolayers treated with LDL or oxLDL and 17beta-estradiol, progesterone or beta-sitosterol. Monocyte chemotactic activity was performed in Transwell chambers by culturing HUVECs with different stimuli and steroids, THP-1 cells labeled with [(3)H] thymidine were added to the upper chamber and the radioactivity was measured. Migration assays were performed using Transwell chambers but monocytes were labeled with BCECF-AM and THP-1 cells adhered to HUVECs were visualized by fluorescence microscopy. MCP-1 was quantified by ELISA.


RESULTS
ICAM-1 expression was inhibited by beta-sitosterol alone, when combined with 17beta-estradiol or progesterone, or with both hormones. It was shown that 7.5 microM beta-sitosterol decreased migration and adhesion of THP-1 cells to HUVECs cultured in the presence of oxLDL. This effect was also observed in HUVEC cultures in the presence of beta-sitosterol, the 17beta-estradiol and progesterone mixture, and in the presence of the two hormones. It was shown that 7.5 microM beta-sitosterol significantly inhibited chemotaxis of [(3)H] thymidine labeled THP-1 cells in oxLDL-stimulated HUVEC cultures. MCP-1 concentrations in the supernatants of oxLDL-stimulated HUVEC cultures were inhibited by 7.5 microM beta-sitosterol as well as by progesterone and the mixture of the two female hormones.
Bustos
Paulina
P
Departamento Bioquímica Clínica e Inmunología, Facultad de Farmacia, Universidad de Concepción, Concepción, Chile. pbustos@udec.cl
Duffau
Cristiane
C
Pacheco
Carolina
C
Ulloa
Natalia
N
D002448:Cell Adhesion / Q000187:drug effects; D002478:Cells, Cultured; D018932:Chemokine CCL2 / Q000187:drug effects / Q000378:metabolism; D002633:Chemotaxis / Q000187:drug effects; D018920:Coculture Techniques; D042783:Endothelial Cells / Q000187:drug effects*; D004958:Estradiol / Q000494:pharmacology; D006801:Humans; D000960:Hypolipidemic Agents / Q000494:pharmacology*; D018799:Intercellular Adhesion Molecule-1 / Q000187:drug effects / Q000378:metabolism; D009000:Monocytes / Q000187:drug effects*; D011374:Progesterone / Q000494:pharmacology; D012855:Sitosterols / Q000494:pharmacology*; D014471:Umbilical Veins / Q000166:cytology
C111835:CCL2 protein, human; D018932:Chemokine CCL2; D000960:Hypolipidemic Agents; D012855:Sitosterols; D018799:Intercellular Adhesion Molecule-1; D011374:Progesterone; D004958:Estradiol; C025473:gamma-sitosterol