This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Hink, U. Articles by Munzel, T. Search for Related Content PubMed PubMed Citation Articles by Hink, U. Articles by Munzel, T. Related Collections Gene expression Other arteriosclerosis Other diabetes Oxidant stress Endothelium/vascular type/nitric oxide

(Circulation Research. 2001;88:e14.)
© 2001 American Heart Association, Inc.

UltraRapid Communication

Mechanisms Underlying Endothelial Dysfunction in Diabetes Mellitus

Ulrich Hink¹, Huige Li¹, Hanke Mollnau, Mathias Oelze, Edi Matheis, Mark Hartmann, Mikhail Skatchkov, Friedrich Thaiss, Rolf A. K. Stahl, Ascan Warnholtz, Thomas Meinertz, Kathy Griendling, David G. Harrison, Ulrich Forstermann, Thomas Munzel

From the Universitätskrankenhaus Eppendorf (U.H., H.M., M.O., E.M., M.H., M.S., A.W., T. Meinertz, T. Munzel), Medizinische Klinik, Kardiologie und Nephrologie (F.T., R.A.K.S.), Hamburg, Germany; Division of Cardiology (K.G., D.G.H.), Emory University, Atlanta, Ga; and Department of Pharmacology (H.L., U.F.), Johannes Gutenberg University, Mainz, Germany.

Correspondence to Thomas Münzel, MD, Universitätskrankenhaus Eppendorf, Abteilung für Kardiologie, Martinistrasse 52, 20246 Hamburg, Germany. E-mail muenzel{at}uke.uni-hamburg.de

Abstract—Incubation of endothelial cells in vitro with high concentrations of glucose activates protein kinase C (PKC) and increases nitric oxide synthase (NOS III) gene expression as well as superoxide production. The underlying mechanisms remain unknown. To address this issue in an in vivo model, diabetes was induced with streptozotocin in rats. Streptozotocin treatment led to endothelial dysfunction and increased vascular superoxide production, as assessed by lucigenin- and coelenterazine-derived chemiluminescence. The bioavailability of vascular nitric oxide (as measured by electron spin resonance) was reduced in diabetic aortas, although expression of endothelial NOS III (mRNA and protein) was markedly increased. NOS inhibition with N^G-nitro-L-arginine increased superoxide levels in control vessels but reduced them in diabetic vessels, identifying NOS as a superoxide source. Similarly, we found an activation of the NADPH oxidase and a 7-fold increase in gp91^phox mRNA in diabetic vessels. In vitro PKC inhibition with chelerythrine reduced vascular superoxide in diabetic vessels, whereas it had no effect on superoxide levels in normal vessels. In vivo PKC inhibition with N-benzoyl-staurosporine did not affect glucose levels in diabetic rats but prevented NOS III gene upregulation and NOS-mediated superoxide production, thereby restoring vascular nitric oxide bioavailability and endothelial function. The reduction of superoxide in vitro by chelerythrine and the normalization of NOS III gene expression and reduction of superoxide in vivo by N-benzoyl-staurosporine point to a decisive role of PKC in mediating these phenomena and suggest a therapeutic potential of PKC inhibitors in the prevention or treatment of vascular complications of diabetes mellitus. The full text of this article is available at http://www.circresaha.org.

Key Words: diabetes • nitric oxide synthase • protein kinase C • uncoupling • NADPH oxidase

This article has been cited by other articles:

				P. M. Thule, A. G. Campbell, D. J. Kleinhenz, D. E. Olson, J. J. Boutwell, R. L. Sutliff, and C. M. Hart Hepatic insulin gene therapy prevents deterioration of vascular function and improves adipocytokine profile in STZ-diabetic rats Am J Physiol Endocrinol Metab, January 1, 2006; 290(1): E114 - E122. [Abstract] [Full Text] [PDF]

				M. Satoh, S. Fujimoto, Y. Haruna, S. Arakawa, H. Horike, N. Komai, T. Sasaki, K. Tsujioka, H. Makino, and N. Kashihara NAD(P)H oxidase and uncoupled nitric oxide synthase are major sources of glomerular superoxide in rats with experimental diabetic nephropathy Am J Physiol Renal Physiol, June 1, 2005; 288(6): F1144 - F1152. [Abstract] [Full Text] [PDF]

				J. Bauersachs and A. Schafer Tetrahydrobiopterin and eNOS dimer/monomer ratio-a clue to eNOS uncoupling in diabetes? Cardiovasc Res, March 1, 2005; 65(4): 768 - 769. [Full Text] [PDF]

				J.-M. Li and A. M Shah Endothelial cell superoxide generation: regulation and relevance for cardiovascular pathophysiology Am J Physiol Regulatory Integrative Comp Physiol, November 1, 2004; 287(5): R1014 - R1030. [Abstract] [Full Text] [PDF]

				J. Widder, T. Behr, D. Fraccarollo, K. Hu, P. Galuppo, P. Tas, C. E Angermann, G. Ertl, and J. Bauersachs Vascular endothelial dysfunction and superoxide anion production in heart failure are p38 MAP kinase-dependent Cardiovasc Res, July 1, 2004; 63(1): 161 - 167. [Abstract] [Full Text] [PDF]

				M. M. Tarpey, D. A. Wink, and M. B. Grisham Methods for detection of reactive metabolites of oxygen and nitrogen: in vitro and in vivo considerations Am J Physiol Regulatory Integrative Comp Physiol, March 1, 2004; 286(3): R431 - R444. [Abstract] [Full Text] [PDF]

				A. K. Trauernicht, H. Sun, K. P. Patel, and W. G. Mayhan Enalapril Prevents Impaired Nitric Oxide Synthase-Dependent Dilatation of Cerebral Arterioles in Diabetic Rats Stroke, November 1, 2003; 34(11): 2698 - 2703. [Abstract] [Full Text] [PDF]

				K. K. Griendling and G. A. FitzGerald Oxidative Stress and Cardiovascular Injury: Part II: Animal and Human Studies Circulation, October 28, 2003; 108(17): 2034 - 2040. [Full Text] [PDF]

				A. S. M. Shamsuzzaman, B. J. Gersh, and V. K. Somers Obstructive Sleep Apnea: Implications for Cardiac and Vascular Disease JAMA, October 8, 2003; 290(14): 1906 - 1914. [Abstract] [Full Text] [PDF]

				R. Marfella, K. Esposito, D. Giugliano, F. Cosentino, M. Eto, B. van der Loo, A. Kouroedov, C. Delli Gatti, H. Joch, T. F. Luscher, et al. Effect of High Glucose on Vasculature * Response Circulation, September 9, 2003; 108 (10): e74 - e74. [Full Text] [PDF]

				L. J. Dixon, D. R. Morgan, S. M. Hughes, L. T. McGrath, N. A. El-Sherbeeny, R. D. Plumb, A. Devine, W. Leahey, G. D. Johnston, and G. E. McVeigh Functional Consequences of Endothelial Nitric Oxide Synthase Uncoupling in Congestive Cardiac Failure Circulation, April 8, 2003; 107(13): 1725 - 1728. [Abstract] [Full Text] [PDF]

				G. Nickenig and D. G. Harrison The AT1-Type Angiotensin Receptor in Oxidative Stress and Atherogenesis: Part I: Oxidative Stress and Atherogenesis Circulation, January 22, 2002; 105(3): 393 - 396. [Full Text] [PDF]

				T. J. Guzik, S. Mussa, D. Gastaldi, J. Sadowski, C. Ratnatunga, R. Pillai, and K. M. Channon Mechanisms of Increased Vascular Superoxide Production in Human Diabetes Mellitus: Role of NAD(P)H Oxidase and Endothelial Nitric Oxide Synthase Circulation, April 9, 2002; 105(14): 1656 - 1662. [Abstract] [Full Text] [PDF]