Oleacein enhances anti-inflammatory activity of human macrophages by increasing CD163 receptor expression

Background: Oleacein (dialdehydic form of decarboxymethyl elenolic acid linked to hydroxytyrosol: 3,4-DHPEA-EDA) have been proven to possess antioxidant and anti-inflammatory activity. Purpose: In this study, we examined whether oleacein could increase CD 163 and IL-10 receptor expression as well as HO-1 intracellular secretion in human macrophages. Methods: Effect of oleacein (10 and 20 mu mol/l) or oleacein together with complexes of haemoglobin (Hb) and haptoglobin 1-1 (Hp11) or haptoglobin 2-2 (Hp22) on expression of IL-10 and CD163 receptor was determined by Flow Cytometry. Expression of CD163mRNA was measured by real-time quantitative RT-PCR. Heme oxygenase 1 (HO-1) intracellular secretion in macrophages was investigated by enzyme-linked immunosorbent assay (ELISA). Results: Oleacein (OC) together with complexes HbHp11 or HbHp22 stimulated the expression of CD163 (30-100-fold), IL-10 (170-300-fold) and HO-1 secretion (60-130-fold) after 5 days of coincubation. The 2-fold (24 h), 4-fold (48 h) increase of CD163 mRNA level and its final (72 h) decrease was also observed. Conclusion: Our results suggested that oleacein enhances anti-inflammatory activity of complexes haemoglobin with haptoglobin 1-1 and 2-2 and could play a potential role in the prevention of inflammatory disease related to atherosclerosis. (C) 2015 Elsevier GmbH. All rights reserved.