Effects of adiponectin on markers of endothelial activation and markers of inflammation in human coronary artery endothelial cells

Abstract

This study investigates the effect of adiponectin on endothelial activation and inflammatory marker secretion by human coronary artery endothelial cells (HCEAC) in vitro.
Methodology: HCAEC at the seventh passage were divided into two groups and incubated or 24 hours at 37° C and 5% CO2 as follows: Control, and adiponectin-treated (30 μg/ml adiponectin) groups. Supernatants were analysed for ICAM-1, E-selectin, PAI-1 and IL-6 and COX-2 using ELISA. RT-PCR was used to analyse gene expression of ICAM-1, E-selectin, PAI-, IL-6, COX-2, NFkBp50 and NFkBp65. Data were analysed using independent t-test.
Results: ICAM-1 and E-selectin level was significantly higher in leptin-adiponectin-treated groups (P<0.01). Endothelial activation marker protein level have no significant difference in adiponectin group when compared to control group.  mRNA expression showed significant increase in adiponectin group as compared to control. PAI-1 and COX-2 showed no significant increase in the level of protein in adiponectin group but IL-6 showed significant increased in the protein level (P<0.001) while mRNA expression of PAI-1 (P<0.05), COX-2 (P<0.01) and IL-6 (P<0.001) showed significant increase in treated group as compared to control. mRNA expression also showed significant increase in both the NFkBp50 and NFkBp65 signalling pathway.
Conclusion: Adiponectin increases the secretion of IL-6 from HCEAC. This adipokines
might have a significant role in the inflammatory and pro-atherogenic state of obesity.

Keywords: HCAEC, Adiponectin, ICAM-1, E-selectin, IL-6, PAI-1, COX-2, NFkB.