The Endothelial Glycocalyx as a Double-Edged Sword in Microvascular Homeostasis and Pathogenesis

Expressed on the endothelial cell (EC) surface of blood vessels, the glycocalyx (GCX), a mixture of carbohydrates attached to proteins, regulates the access of cells and molecules in the blood to the endothelium. Besides protecting endothelial barrier integrity, the dynamic microstructure of the GCX confers remarkable functions including mechanotransduction and control of vascular tone. Recently, a novel perspective has emerged supporting the pleiotropic roles of the endothelial GCX (eGCX) in cardiovascular health and disease. Because eGCX degradation occurs in certain pathological states, the circulating levels of eGCX degradation products have been recognized to have diagnostic or prognostic values. Beyond their biomarker roles, certain eGCX fragments serve as pathogenic factors in disease progression. Pharmacological interventions that attenuate eGCX degradation or restore its integrity have been sought. This review provides our current understanding of eGCX structure and function across the microvasculature in different organs. We also discuss disease or injury states, such as infection, sepsis and trauma, where eGCX dysfunction contributes to severe inflammatory vasculopathy.

Automated summary

The glycocalyx (GCX) on the endothelial cell surface of blood vessels plays important roles in regulating access to the endothelium, protecting barrier integrity, and controlling vascular tone. Recent perspectives highlight the pleiotropic roles of the endothelial GCX (eGCX) in cardiovascular health and disease, with potential diagnostic or prognostic values in certain pathological states. Pharmacological interventions targeting eGCX degradation are being explored, particularly in disease states where eGCX dysfunction contributes to severe inflammatory vasculopathy.