NAD(P)H oxidase-stimulating activity of serum from type 2 diabetic patients with retinopathy mediates enhanced endothelial expression of E-selectin.
Endothelial expression of E-selectin is enhanced in diabetic patients with retinopathy, however, the underlying mechanisms are unclear. Therefore, this study was aimed to determine if endothelial expression of E-selectin is stimulated with serum from type 2 diabetic patients with retinopathy, and whether this process is related to NAD(P)H oxidase-derived oxidative stress. Serum was obtained from type 2 diabetic patients with (T2DR) or without (T2DM) retinopathy, and age-matched non-diabetic healthy person (Control). Serum was added to in vitro-grown human coronary artery endothelial cells (HCAEC), after which E-selectin expression, reactive oxygen species (ROS) production, and NAD(P)H oxidase activity were measured. Serum from T2DR induced a significantly higher expression of E-selectin than serum from T2DM and control in association with an enhanced production of ROS in HCAEC. T2DR serum enhanced E-selectin expression in a ROS-dependent manner since this process was significantly attenuated not only by tiron (1 mM), a superoxide scavenger, but also by DPI (10 micromol/L) and apocynin (100 micromol/L), inhibitors of NAD(P)H oxidase. Furthermore, the activity of NADH oxidase was markedly increased by T2DR serum, and this was accompanied by the enhanced membrane translocation of p47phox, a cytosolic subunit of NAD(P)H oxidase. These findings suggest that serum from T2DR induced up-regulation of E-selectin expression in HCAEC, and this process might be dependent on activation of endothelial NADH oxidase via an enhanced membrane translocation of p47phox.
Yun
Mi Ran
MR
Department of Pharmacology, College of Medicine, MRC for Ischemic Tissue Regeneration and Medical Research Institute, South Korea.
Im
Dong Sun
DS
Lee
Jong-Soo
JS
Son
Seok Man
SM
Sung
Sang-Min
SM
Bae
Sun Sik
SS
Kim
Chi Dae
CD
D014013:1,2-Dihydroxybenzene-3,5-Disulfonic Acid Disodium Salt / Q000494:pharmacology; D000098:Acetophenones / Q000494:pharmacology; D000975:Antioxidants / Q000494:pharmacology; D002478:Cells, Cultured; D003331:Coronary Vessels / Q000166:cytology / Q000378:metabolism; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000150:complications; D003930:Diabetic Retinopathy / Q000097:blood* / Q000209:etiology; D019040:E-Selectin / Q000378:metabolism*; D004730:Endothelium, Vascular / Q000166:cytology / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005260:Female; D016166:Free Radical Scavengers / Q000494:pharmacology; D006801:Humans; D007202:Indicators and Reagents / Q000494:pharmacology; D008297:Male; D008875:Middle Aged; D019255:NADPH Oxidases / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism; D044967:Serum / Q000502:physiology*
D000098:Acetophenones; D000975:Antioxidants; D019040:E-Selectin; D004791:Enzyme Inhibitors; D016166:Free Radical Scavengers; D007202:Indicators and Reagents; D017382:Reactive Oxygen Species; D014013:1,2-Dihydroxybenzene-3,5-Disulfonic Acid Disodium Salt; C056165:acetovanillone; D019255:NADPH Oxidases