Glycosaminoglycans, hyperglycemia, and disease
Linda M Hiebert1, Juying Han, Anil Kumar Mandal
11 Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan , Saskatoon, Canada .
Antioxidants & Redox Signaling
|November 15, 2013
Summary
Diabetes causes endothelial injury, leading to complications. Preserving heparan sulfate proteoglycans may prevent these issues by increasing endothelial heparan sulfate and reducing heparanase activity.
Area of Science:
- Endocrinology
- Vascular Biology
- Biochemistry
Background:
- Diabetes mellitus is a global health concern with increasing incidence despite pharmaceutical interventions.
- Hyperglycemia in diabetes damages endothelial cells, contributing to microvascular and macrovascular complications like nephropathy, retinopathy, neuropathy, and atherosclerosis.
- Heparan sulfate proteoglycans (HSPGs) are crucial for endothelial cell function, regulating growth and acting as reservoirs for bioactive molecules.
Purpose of the Study:
- To investigate the role of heparan sulfate proteoglycans in diabetes-induced endothelial dysfunction.
- To explore the potential of glycosaminoglycans (GAGs) and GAG-like compounds in preserving endothelial health in diabetic conditions.
- To understand the impact of hyperglycemia on heparan sulfate levels and heparanase activity.
Main Methods:
- Analysis of endothelial cell alterations in hyperglycemia.
- Assessment of heparan sulfate levels and heparanase enzyme activity.
- Evaluation of reactive oxygen species' impact on glycosaminoglycans.
Main Results:
- Hyperglycemia leads to a reduction in endothelial heparan sulfate and an increase in heparanase, an enzyme that degrades HSPGs.
- Reactive oxygen species, elevated in diabetes, further contribute to GAG degradation.
- Preserving HSPGs on endothelial cells presents a potential strategy to mitigate diabetes-associated angiopathy.
Conclusions:
- Maintaining endothelial heparan sulfate may prevent diabetic angiopathy.
- Glycosaminoglycans and GAG-like compounds show promise in increasing endothelial heparan sulfate and inhibiting heparanase.
- Further research into GAGs' role in endothelial health and heparanase modulation is crucial for developing novel diabetes treatments and preventing cardiovascular complications.
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