[157-POS] : Silibinin modulates monocytes M1/M2 profile in women with preeclampsia.

OBJECTIVES: Pre-eclampsia is a human pregnancy-specific disease characterized by an excessive maternal inflammatory response. The systemic environment in preeclampsia differentiates and polarizes peripheral blood monocytes to the M1 phenotype. Then, the use of substances modulating the monocyte activity could be useful in the treatment of patients with this disorder. Silibinin is the main component of silymarin, a polyphenolic extract obtained from fruits and seeds of Sylibum marianum with potent hepatoprotective and anti-inflammatory activities. This study investigated whether monocytes treatment with silibinin modulates the M1/M2 monocytes profile by evaluation of surface receptors characteristic of M1 (TLR2, TLR4 and CD64) or M2 (CD163 and CD206) in preeclamptic women.

METHODS: Thirty pregnant women with preeclampsia and 20 normotensive pregnant women matched for gestational age were studied. Monocytes obtained from peripheral blood were cultured with or without silibinin (5μM or 50μM) and were stimulated with lipopolysaccharide (LPS) for 18 h on order to determine the surface markers TLR2, TLR4, CD64, CD163 and CD206 by flow cytometry.

RESULTS: Monocytes from preeclamptic women showed higher expression of TLR4 and CD64 compared with normotensive pregnant women. A significant inhibition of this M1 phenotype was observed after treatment with silibinin (50μM) in cells from preeclampsia and normotensive groups stimulated with LPS. There was no statistically significant difference in TLR2 expression even after treatment with silibinin. Monocytes cultures from preeclamptic group treated with 50μM of silibinin led to increase in CD163 and CD206 expression. Thus, silibinin at concentration of 50μM showed an anti-inflammatory activity, inhibiting M1 profile and enhancing M2 phenotype of monocytes from preeclamptic women.

CONCLUSIONS: This study provides evidence that the unbalanced M1/M2 phenotype of human monocytes in preeclamptic women may be modulated by in vitro silibinin treatment and suggests its use as adjuvant in preeclampsia therapy. Financial support: FAPESP 2010/00985-9.

DISCLOSURES: C.F. Bannwart-Castro: None. J.C. Peracoli: None. I.C. Weel: None. M. Romao: None. L.T. Medeiros: None. L.G. Oliveira: None. M.T. Peracoli: None.