TITLE:
The influence of exendin and GLP-1 on VCAM-1 and ICAM-1 production in endothelium stimulated by TNF-α and glycated albumin
AUTHORS:
Krzysztof Siemianowicz, Tomasz Francuz, Wojciech Garczorz
KEYWORDS:
Incretins; Endothelium; Adhesion Molecules
JOURNAL NAME:
Health,
Vol.4 No.12A,
December
31,
2012
ABSTRACT:
A growing body of
evidence indicates that incretins may have pleiotropic beneficial effects
beyond lowering glucose blood concentration. The effect of GLP-1 and exendin-4
on coronary arteries endothelium in diabetic and obese individuals has been
studied widely. TNF-a is one of adipocytokines.
The aim of our study was to evaluate the influence of glycated albumin
(GlyAlb; 100; 500 and 1000 mg/L) and proinflammatory cytokine, TNF-α (2.5 and 10 ng/mL), on expression of
ICAM-1 and VCAM-1 in cultured human endothelial cells derived from coronary
arteries. The next goal of the study was to evaluate the influence of GLP-1 (10
nM and 100 nM) and its analogue, exendin-4 (1 nM and 10 nM), on the expression
of ICAM-1 and VCAM-1 in these cell line. TNF-a statistically significantly increased VCAM-1 production by endothelial cells,
whereas GlyAlb statistically significantly augmented the expression of both tested adhesion mole- cules. Exendin-4 and GLP-1 statistically significantly reduced the expression of VCAM-1 in endothelial
cells stimulated by GlyAlb in dose-de- pendent manner. When TNF-a was used as the stimulant only exendin-4 in the concentration of 10 nM
statistically significantly reduced the expression of VCAM-1. Studied incretins
in their both concentrations statistically significantly reduced the expression
of ICAM-1 in endothelial cells stimulated by GlyAlb. The influence of TNF- a on the expression of ICAM-1 was statistically significantly reduced by both
concentrations of exendin-4 but only by the higher concentration of GLP-1. The
results of our present study indicate
that incretins may present a group of agents developing pleiotropic
effects beyond the reduction of blood glucose concentration. Their vaso-protective
and cardioprotective action may be of importance in diabetic and obese individuals.