Background/Aims: Dysfunction of endothelial progenitor cell (EPCs) contributes to diabetic vascular disease. We reported that downregulated miR-126 in diabetic patients causes EPC dysfunction. The study was designed to investigate how high glucose (HG) and advanced glycation end products (AGEs) regulate miR-126 expression and whether miR-126 mediates the effects of HG and AGEs on EPCs. Methods: We first tested the effects of glucose (5.5-50 mM) and AGEs at 50-200 mg/l on EPC proliferation and selected HG at 50 mM and AGEs at 50 mg/l for further experiments. EPCs were stimulated with HG and AGEs, and miR-126 expression was measured by real-time PCR. Reactive oxygen species (ROS) were measured by immunofluorescence microscopy and flow cytometry. IL-6 and TNF-α levels in EPC supernatants were determined by ELISA. The effects of miR-126 on ROS and inflammatory markers under stimulation of HG and AGEs were also assessed. Finally, the effects of inhibitors of PI3K and Akt on AGE-mediated miR-126 expression were examined. Results: HG and AGEs increased IL-6, TNF-α and ROS and decreased miR-126 expression in EPCs. miR-126 negatively regulated IL-6, TNF-α and ROS. miR-126 overexpression reduced and miR-126 inhibition further increased the inflammatory markers and ROS induced by HG and AGEs. Inhibitors of PI3K and Akt further decreased miR-126 expression in the presence of AGEs. Conclusions: In conclusion, hyperglycemia and AGEs decrease miR-126 expression in EPCs. Recovering miR-126 expression may protect EPCs against dysfunction induced by HG and AGEs.

Keywords:
Advanced glycation end products, miR-126, Endothelial progenitor cells, Hyperglycemia
1.
Waltenberger J: Impaired collateral vessel development in diabetes: potential cellular mechanisms and therapeutic implications. Cardiovasc Res 2001;49:554-560.
2.
Walter DH, Rittig K, Bahlmann FH, Kirchmair R, Silver M, Murayama T, Nishimura H, Losordo DW, Asahara T, Isner JM: Statin therapy accelerates reendothelialization: a novel effect involving mobilization and incorporation of bone marrow-derived endothelial progenitor cells. Circulation 2002;105:3017-3024.
3.
Werner N, Priller J, Laufs U, Endres M, Böhm M, Dirnagl U, Nickenig G: Bone marrow- derived progenitor cells modulate vascular reendothelialization and neointimal formation: effect of 3-hydroxy-3-methylglutaryl coenzyme a reductase inhibition. Arterioscler Thromb Vasc Biol 2002;22:1567-1572.
4.
Xu Q: Progenitor cells in vascular repair. Curr Opin Lipidol 2007;18:534-539.
5.
Sata M: Role of circulating vascular progenitors in angiogenesis, vascular healing, and pulmonary hypertension: lessons from animal models. Arterioscler Thromb Vasc Biol 2006;26:1008-1014.
6.
Tepper OM, Galiano RD, Capla JM, Kalka C, Gagne PJ, Jacobowitz GR, Levine JP, Gurtner GC: Human endothelial progenitor cells from type II diabetics exhibit impaired proliferation, adhesion, and incorporation into vascular structures. Circulation 2002;106:2781-2786.
7.
Fadini GP, Sartore S, Schiavon M, Albiero M, Baesso I, Cabrelle A, Agostini C, Avogaro A: Diabetes impairs progenitor cell mobilisation after hindlimb ischaemia-reperfusion injury in rats. Diabetologia 2006;49:3075-3084.
8.
Fadini GP, Miorin M, Facco M, Bonamico S, Baesso I, Grego F, Menegolo M, de Kreutzenberg SV, Tiengo A, Agostini C, Avogaro A: Circulating endothelial progenitor cells are reduced in peripheral vascular complications of type 2 diabetes mellitus. J Am Coll Cardiol 2005;45:1449-1457.
9.
Zhou B, Wu KH, Poon MC, Han ZC: Endothelial progenitor cells transfected with PDGF: cellular and molecular targets for prevention of diabetic microangiopathy. Med Hypotheses 2006;67:1308-1312.
10.
Urbich C, Kuehbacher A, Dimmeler S: Role of microRNAs in vascular diseases, inflammation, and angiogenesis. Cardiovasc Res 2008;79:581-588.
11.
Meng S, Cao JT, Zhang B, Zhou Q, Shen CX, Wang CQ: Downregulation of microRNA- 126 in endothelial progenitor cells from diabetes patients, impairs their functional properties, via target gene Spred-1. J Mol Cell Cardiol 2012;53:64-72.
12.
Chen J, Song M, Yu S, Gao P, Yu Y, Wang H, Huang L: Advanced glycation end products alter functions and promote apoptosis in endothelial progenitor cells through receptor for advanced glycation end products mediate overexpression of cell oxidant stress. Mol Cell Biochem 2010;335:137-146.
13.
Li H, Zhang X, Guan X, Cui X, Wang Y, Chu H, Cheng M: Advanced glycation end products impair the migration, adhesion and secretion potentials of late endothelial progenitor cells. Cardiovasc Diabetol 2012;11:46.
14.
Zhang W, Wang XH, Chen SF, Zhang GP, Lu N, Hu RM, Jin HM: Biphasic response of endothelial progenitor cell proliferation induced by high glucose and its relationship with reactive oxygen species. J Endocrinol 2008;197:463-470.
15.
Chen YH, Lin SJ, Lin FY, Wu TC, Tsao CR, Huang PH, Liu PL, Chen YL, Chen JW: High glucose impairs early and late endothelial progenitor cells by modifying nitric oxide-related but not oxidative stress-mediated mechanisms. Diabetes 2007;56:1559-1568.
16.
Xu B, Chibber R, Ruggiero D, Kohner E, Ritter J, Ferro A: Impairment of vascular endothelial nitric oxide synthase activity by advanced glycation end products. FASEB J 2003;17:1289-1291.
17.
Marchetti V, Menghini R, Rizza S, Vivanti A, Feccia T, Lauro D, Fukamizu A, Lauro R, Federici M: Benfotiamine counteracts glucose toxicity effects on endothelial progenitor cell differentiation via Akt/FoxO signaling. Diabetes 2006;55:2231-2237.
18.
Kränkel N, Adams V, Linke A, Gielen S, Erbs S, Lenk K, Schuler G, Hambrecht R: Hyperglycemia reduces survival and impairs function of circulating blood-derived progenitor cells. Arterioscler Thromb Vasc Biol 2005;25:698-703.
19.
Kuki S, Imanishi T, Kobayashi K, Matsuo Y, Obana M, Akasaka T: Hyperglycemia accelerated endothelial progenitor cell senescence via the activation of p38 mitogen-activated protein kinase. Circ J 2006;70:1076-1081.
20.
Schleicher E, Friess U: Oxidative stress, AGE, and atherosclerosis. Kidney Int Suppl 2007;106:S17-S26.
21.
Unoki H, Yamagishi S: Advanced glycation end products and insulin resistance. Curr Pharm Des 2008;14:987-989.
22.
Chen Q, Dong L, Wang L, Kang L, Xu B: Advanced glycation end products impair function of late endothelial progenitor cells through effects on protein kinase Akt and cyclooxygenase-2. Biochem Biophys Res Commun 2009;381:192-197.
23.
Jandeleit-Dahm K, Watson A, Soro-Paavonen A: The AGE/RAGE axis in diabetes-accelerated atherosclerosis. Clin Exp Pharmacol Physiol 2008;35:329-334.
24.
Maulik N: Redox signaling of angiogenesis. Antioxid Redox Signal 2002;4:805-815.
25.
Ushio-Fukai M: Redox signaling in angiogenesis: role of NADPH oxidase. Cardiovasc Res 2006;71:226-235.
26.
Case J, Ingram DA, Haneline LS: Oxidative stress impairs endothelial progenitor cell function. Antioxid Redox Signal 2008;10:1895-1907.
27.
Wang J, Li G, Wang Z, Zhang X, Yao L, Wang F, Liu S, Yin J, Ling EA, Wang L, Hao A: High glucose-induced expression of inflammatory cytokines and reactive oxygen species in cultured astrocytes. Neuroscience 2012;202:58-68.
28.
Ksiazek K, Breborowicz A, Jorres A, Witowski J: Oxidative stress contributes to accelerated development of the senescent phenotype in human peritoneal mesothelial cells exposed to high glucose. Free Radic Biol Med 2007;42:636-641.
29.
Zhang H, Park Y, Wu J, Chen X, Lee S, Yang J, Dellsperger KC, Zhang C: Role of TNF-α in vascular dysfunction. Clin Sci 2009;116:219-230.
30.
Desouza CV, Hamel FG, Bidasee K, O'Connell K: Role of inflammation and insulin resistance in endothelial progenitor cell dysfunction. Diabetes 2011;60:1286-1294.
31.
Grisar J, Aletaha D, Steiner CW, Kapral T, Steiner S, Saemann M, Schwarzinger I, Buranyi B, Steiner G, Smolen JS: Endothelial progenitor cells in active rheumatoid arthritis: effects of tumour necrosis factor and glucocorticoid therapy. Ann Rheum Dis 2007;66:1284-1288.
32.
Verma S, Kuliszewski MA, Li SH, Szmitko PE, Zucco L, Wang CH, Badiwala MV, Mickle DA, Weisel RD, Fedak PW, Stewart DJ, Kutryk MJ: C-reactive protein attenuates endothelial progenitor cell survival, differentiation, and function: further evidence of a mechanistic link between C-reactive protein and cardiovascular disease. Circulation 2004;109:2058-2067.
33.
Gao X, Belmadani S, Picchi A, Xu X, Potter BJ, Tewari-Singh N, Capobianco S, Chilian WM, Zhang C: Tumor necrosis factor-α induces endothelial dysfunction in Leprdb mice. Circulation 2007;115:245-254.
34.
Puthanveetil P, Chen S, Feng B, Gautam A, Chakrabarti S: Long non-coding RNA MALAT1 regulates hyperglycaemia induced inflammatory process in the endothelial cells. J Cell Mol Med 2015;19:1418-1425.
35.
Liang C, Ren Y, Tan H, He Z, Jiang Q, Wu J, Zhen Y, Fan M, Wu Z: Rosiglitazone via upregulation of Akt/eNOS pathways attenuates dysfunction of endothelial progenitor cells, induced by advanced glycation end products. Br J Pharmacol 2009;158:1865-1873.
36.
Xia L, Wang XX, Hu XS, Guo XG, Shang YP, Chen HJ, Zeng CL, Zhang FR, Chen JZ: Resveratrol reduces endothelial progenitor cells senescence through augmentation of telomerase activity by Akt-dependent mechanisms. Br J Pharmacol 2008;155:387-394.
© 2016 S. Karger AG, Basel
2016
Copyright / Drug Dosage / Disclaimer
Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.
You do not currently have access to this content.