Primary HCAEC - human coronary artery endothelial cells transfected with SilenceMag transfection reagent

HCAECs isolated from normal human coronary arteries were transfected with siRNA using SilenceMag transfection reagent.

This article highlights the capacity of Magnetofection technology to efficiently transfect Primary endothelial cells (HCAEC) with siRNA. SilenceMag from OZ Biosciences was used in this work.

paper reference: J Mol Endocrinol. 2013 Jan 23.

Exendin-4 protects endothelial cells from lipoapoptosis by PKA PI3K eNOS p38MAPK and JNK pathways.
Erdogu O, Eriksson L, Xu H, Sjöholm A, Zhang Q, Nyström T.

Abstract

Experimental studies have indicated that endothelial cells play an important role in maintaining vascular homeostasis. We previously reported that human coronary artery endothelial cells (HCAECs) express the glucagon-like peptide 1 (GLP-1) receptor and that the stable GLP-1 mimetic exendin-4 is able to activate the receptor, leading to increased cell proliferation. Here we have studied the effect of exendin-4 and native GLP-1 (7-36) on lipoapoptosis and its underlying mechanisms in HCAECs. Apoptosis was assessed by DNA fragmentation and caspase-3 activation, after incubating cells with palmitate. Nitric oxide (NO) and reactive oxidative species (ROS) were analyzed. GLP-1 receptor activation, PKA, PI3K/Akt, eNOS, p38 MAPK and JNK dependent pathways, and genetic silencing of transfection of eNOS, were also studied. Palmitate-induced apoptosis stimulated cells to release NO and ROS, concomitant with upregulation of eNOS, which required activation of p38 MAPK and JNK. Exendin-4 restored the imbalance between NO and ROS production in which ROS production decreased and NO production was further augmented. Incubation with exendin-4 and GLP-1 (7-36) protected HCAECs against lipoapoptosis, an effect that was blocked by PKA, PI3K/Akt, eNOS, p38 MAPK and JNK inhibitors. Genetic silencing of eNOS also abolished the antiapoptotic effect afforded by exendin-4. Our results support the notion that GLP-1 receptor agonists restore eNOS-induced ROS production due to lipotoxicity and that such agonists protect against lipoapoptosis through PKA-PI3K/Akt-eNOS-p38 MAPK-JNK dependent pathways via a GLP-1 receptor-dependent mechanism.

SilenceMag from OZ Biosciences is a very efficient siRNA delivery reagent based on Magnetofection™ technology.