In patients with diabetes, hyperglycemia leads to functional impairment of endothelial cells (ECs) and microangiopathy. Inflammation and endothelial dysfunction (ED) have been associated with the development of several cardiovascular complications. Concentration of methylglyoxal (MG) - a highly reactive aldehyde is increased in diabetes. In a non-pathological state, MG is detoxified by the enzymes glyoxalase-1 (GLO1) and glyoxalase 2 in presence of glutathione.
This thesis examines the role of MG accumulation in ECs and bone marrow cells (BMCs), with the consequences it has for their function. To this end, a transgenic mouse model was used in which the human enzyme GLO1 is overexpressed in the vasculature By using a GLO1 overexpressing mouse model studies described here examined the contribution of MG-induced inflammation in vivo to cardiovascular complications of diabetes, namely diabetic heart failure and peripheral vascular disease.
This study confirmed that accumulation of MG leads to inflammation and cell death, and further explained how MG affects the role of ECs in development of the heart failure and BMCs in the revascularization. Overexpression of GLO1 in the vasculature diminished MG-induced inflammation, reduced EC death and delayed and limited the loss of cardiac function in streptozotocin (STZ)-induced diabetic mice (Chapter 2). The in vitro part of this study showed that MG and tumor necrosis factor (TNF- have a synergistic effect on cell death (Chapter 3). Overexpressing the GLO1 in BMCs only, restored neovascularization in ischaemic tissue of mice with STZ-induced diabetes (Chapter 4).
Taken together, the results of this thesis suggest that hyperglycemia increased MG leads to endothelial inflammation, EC death and decreased angiogenic potential of BMCs. Furthermore, this MG-induced inflammation and reduced cell function observed, identifies a potential target for therapy of the cardiovascular complications seen in diabetes.
| Identifer | oai:union.ndltd.org:uottawa.ca/oai:ruor.uottawa.ca:10393/33159 |
| Date | January 2015 |
| Creators | Vulesevic, Branka |
| Contributors | Suuronen, Erik, Milne, Ross |
| Publisher | Université d'Ottawa / University of Ottawa |
| Source Sets | Université d’Ottawa |
| Language | English |
| Detected Language | English |
| Type | Thesis |
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