MicroRNA-126 attenuates palmitate-induced apoptosis by targeting TRAF7 in HUVECs.

The aim of the present study was to explore the role of miR-126 in palmitate-induced HUVECs apoptosis and the possible mechanisms. Palmitate inhibited miR-126 expression in HUVECs, increased reactive oxygen species (ROS) production, and induced apoptosis as determined by up-regulation of caspase-3 activity and DNA fragmentation. Overexpression of miR-126 decreased ROS production, TNF-α expression, and apoptosis in palmitate-stimulated HUVECs. In contrast, miR-126 antagomir enhanced palmitate-induced ROS production, TNF-α expression, and apoptosis. The induction of miR-126 correlated with a reduction in TRAF7. We further showed that miR-126 targeted and inhibited TRAF7 expression through target sites located in the 3' untranslated region of TRAF7 mRNA. In concordance, miR-126 mimic reduced TRAF7 protein in HUVECs, whereas the inhibition of miR-126 increased it. This study demonstrates an anti-apoptotic role of miR-126 in HUVECs and identifies TRAF7 as a direct target of miR-126 in HUVECs.