|
|
|
||||
| Home Help Feedback Subscriptions Archive Search Table of Contents | |||||
First published online December 22, 2004
doi: 10.1242/10.1242/jcs.01612
Research Article |
1 Vascular Biology Center, Medical College of Georgia, Augusta, GA 30912, USA
2 Department of Pharmacology, Medical College of Georgia, Augusta, GA 30912, USA
3 Department of Pathology, Medical College of Georgia, Augusta, GA 30912, USA
4 Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta, GA 30912, USA
5 Department of Ophthalmology, Medical College of Georgia, Augusta, GA 30912, USA
* Author for correspondence (e-mail: aelremessy{at}mcg.edu)
Accepted 20 October 2004
In diabetic retinopathy, endothelial cell apoptosis is paradoxically increased despite upregulation of the potent pro-survival factor VEGF. We tested the hypothesis that elevated glucose levels disrupt VEGF's pro-survival function via peroxynitrite-mediated alteration of the Akt-1/p38 MAP kinase signaling pathway by studies of retinal endothelial cells in vitro. High glucose or exogenous peroxynitrite caused significant increases in apoptosis in the presence or absence of VEGF. Treatment with a peroxynitrite decomposition catalyst blocked these effects, implying a causal role of peroxynitrite. Peroxynitrite or high glucose treatment also increased phosphorylation of p38 MAP kinase, whereas phosphorylation of Akt-1 was significantly decreased in basal or VEGF-stimulated conditions. High glucose- or peroxynitrite-treated cells also showed significant increases in tyrosine nitration on the p85 subunit of PI 3-kinase that blocked PI 3-kinase and Akt-1 kinase activity. Inhibiting peroxynitrite formation or blocking tyrosine nitration of p85 restored the activity of PI 3-kinase and Akt-1 kinase, blocked phosphorylation of p38 MAP kinase and normalized pro-survival function. Transfecting the cells with constitutively active Akt-1 or inhibiting activity of p38 MAP kinase completely masked the pro-apoptotic effects of high glucose and exogenous peroxynitrite, suggesting an interaction between the Akt-1 and p38 MAP kinase pathways. In conclusion, high glucose treatment blocks the pro-survival effect of VEGF and causes accelerated endothelial cell apoptosis via the action of peroxynitrite in causing tyrosine nitration of PI 3-kinase, inhibiting activity of Akt-1 kinase and increasing the activity of p38 MAP kinase.
Key words: Peroxynitrite, High glucose, Apoptosis, Endothelial cells, p38 MAP kinase, Tyrosine nitration, Akt-1
Related articles in JCS:
This article has been cited by other articles:
![]() |
N. Bashan, J. Kovsan, I. Kachko, H. Ovadia, and A. Rudich Positive and Negative Regulation of Insulin Signaling by Reactive Oxygen and Nitrogen Species Physiol Rev, January 1, 2009; 89(1): 27 - 71. [Abstract] [Full Text] [PDF] |
||||
![]() |
Q. Huang and N. Sheibani High glucose promotes retinal endothelial cell migration through activation of Src, PI3K/Akt1/eNOS, and ERKs Am J Physiol Cell Physiol, December 1, 2008; 295(6): C1647 - C1657. [Abstract] [Full Text] [PDF] |
||||
![]() |
I. Tommasini, L. Cerioni, L. Palomba, and O. Cantoni Prostaglandin E2 Signals Monocyte/Macrophage Survival to Peroxynitrite via Protein Kinase A Converging in Bad Phosphorylation with the Protein Kinase C{alpha}-Dependent Pathway Driven by 5-Hydroxyeicosatetraenoic Acid J. Immunol., October 15, 2008; 181(8): 5637 - 5645. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. S. Kern and A. J. Barber Retinal ganglion cells in diabetes J. Physiol., September 15, 2008; 586(18): 4401 - 4408. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Duplain, C. Sartori, P. Dessen, P.-Y. Jayet, M. Schwab, J. Bloch, P. Nicod, and U. Scherrer Stimulation of peroxynitrite catalysis improves insulin sensitivity in high fat diet-fed mice J. Physiol., August 15, 2008; 586(16): 4011 - 4016. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. K. Biswas, Y. Zhao, A. Nagalingam, T. W. Gardner, and L. Sandirasegarane PDGF- and Insulin/IGF-1-Specific Distinct Modes of Class IA PI 3-Kinase Activation in Normal Rat Retinas and RGC-5 Retinal Ganglion Cells Invest. Ophthalmol. Vis. Sci., August 1, 2008; 49(8): 3687 - 3698. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. Takamura, T. Tomomatsu, E. Kubo, S. Tsuzuki, and Y. Akagi Role of the Polyol Pathway in High Glucose-Induced Apoptosis of Retinal Pericytes and Proliferation of Endothelial Cells Invest. Ophthalmol. Vis. Sci., July 1, 2008; 49(7): 3216 - 3223. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. K. Ali, S. Matragoon, B. A. Pillai, G. I. Liou, and A. B. El-Remessy Peroxynitrite Mediates Retinal Neurodegeneration by Inhibiting Nerve Growth Factor Survival Signaling in Experimental and Human Diabetes Diabetes, April 1, 2008; 57(4): 889 - 898. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. B. El-Remessy, M. Al-Shabrawey, D. H. Platt, M. Bartoli, M. A. Behzadian, N. Ghaly, N. Tsai, K. Motamed, and R. B. Caldwell Peroxynitrite mediates VEGF's angiogenic signal and function via a nitration-independent mechanism in endothelial cells FASEB J, August 1, 2007; 21(10): 2528 - 2539. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. Pacher, J. S. Beckman, and L. Liaudet Nitric Oxide and Peroxynitrite in Health and Disease Physiol Rev, January 1, 2007; 87(1): 315 - 424. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Sirinyan, F. Sennlaub, A. Dorfman, P. Sapieha, F. Gobeil Jr, P. Hardy, P. Lachapelle, and S. Chemtob Hyperoxic Exposure Leads to Nitrative Stress and Ensuing Microvascular Degeneration and Diminished Brain Mass and Function in the Immature Subject Stroke, November 1, 2006; 37(11): 2807 - 2815. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y.-J. Zhang, Y.-F. Xu, Y.-H. Liu, J. Yin, H.-L. Li, Q. Wang, and J.-Z. Wang Peroxynitrite induces Alzheimer-like tau modifications and accumulation in rat brain and its underlying mechanisms FASEB J, July 1, 2006; 20(9): 1431 - 1442. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. F. Voelkel, R. W. Vandivier, and R. M. Tuder Vascular endothelial growth factor in the lung Am J Physiol Lung Cell Mol Physiol, February 1, 2006; 290(2): L209 - L221. [Abstract] [Full Text] [PDF] |
||||
![]() |
S.-J. Lee, D.-C. Kim, B.-H. Choi, H. Ha, and K.-T. Kim Regulation of p53 by Activated Protein Kinase C-{delta} during Nitric Oxide-induced Dopaminergic Cell Death J. Biol. Chem., January 27, 2006; 281(4): 2215 - 2224. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. B. El-Remessy, M. Al-Shabrawey, Y. Khalifa, N.-T. Tsai, R. B. Caldwell, and G. I. Liou Neuroprotective and Blood-Retinal Barrier-Preserving Effects of Cannabidiol in Experimental Diabetes Am. J. Pathol., January 1, 2006; 168(1): 235 - 244. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Tsang, D. J. Hausenloy, M. M. Mocanu, R. D. Carr, and D. M. Yellon Preconditioning the Diabetic Heart: The Importance of Akt Phosphorylation Diabetes, August 1, 2005; 54(8): 2360 - 2364. [Abstract] [Full Text] [PDF] |
||||