Abstract 14974: Reactive Oxygen Species Mediated Impairment of the Glycolytic Switch Required Mesenchymal to Endothelial Transition in Hyperglycemia
Purpose: Endothelial Mesenchyme Transition plays a major role in fibrotic disorders associated with diabetes. Recently, the reverse phenomenon i.e., Mesenchyme Endothelial Transition (MEndoT) has been discovered as a physiological response to myocardial ischemia. MEndoT is characterized by fibroblast-derived endothelial cells (iECs) generation that contribute to angiogenesis in ischemic tissue. It is known that angiogenesis is impaired in diabetes and recent studies have also linked changes in energy metabolism with the cell fate determination. This study is to profile the metabolic change during MEndoT and to test whether hyperglycemia impairs MEndoT.
Methods and Results: We have developed a small molecule based in vitro protocol for MEndoT. The iECs induced from this protocol manifest the genetical and functional profile of authentic ECs. Using the Seahorse technology, we discovered a metabolic switch began within the first 72h after induction, characterized by a transition from oxidative phosphorylation to glycolysis. Inhibitors of glycolysis impaired the generation of iECs, whereas agents to enhance glycolysis increased the yield. Intriguingly, when we applied a high glucose (25mM) condition, MEndoT was markedly impaired and this high glucose-induced impairment of MEndoT could be reversed by antioxidants such as n-acetyl cysteine. To develop a model of MEndoT in vivo, we added our small molecule MEndoT formulation to matrigel, together with human GFP-labeled fibroblasts with or without anti-oxidants, and embedded the mixture subcutaneously in streptozotocin-induced diabetic SCID mice. The matrigel plugs were harvested after two weeks and the percentage of GFP+CD31+ cells (human iECs) within the plugs was documented. Our data showed, compare with the healthy control mice, the yield of iECs was largely reduced in hyperglycemic mice, which can be reversed by the co-application of anti-oxidants.
Conclusions: Our study is the first to show: 1. A glycolytic switch is required for MEndoT, 2. MEndoT is impaired by hyperglycemia, 3. ROS scavengers can reverse this impairment. These data shed light on a new physiological mechanism for angiogenesis in response to ischemia, its impairment in hyperglycemia, and its potential therapeutic value.
Author Disclosures: L. Lai: None. E. Reineke: None. D. Hamilton: None. J.P. Cooke: None.
- © 2016 by American Heart Association, Inc.