Endothelial glycocalyx in health and kidney disease: Rising star or false Dawn?
Conventional vascular risk factors such as hypertension, hypercholesterolaemia, diabetes mellitus and smoking only partially explain the high prevalence of cardiovascular disease in patients with chronic kidney disease (CKD).1 Non‐traditional risk factors such as uraemia, inflammation and endothelial dysfunction are increasingly recognized as key contributors to cardiovascular disease, the last of which is characterized by an imbalance between small‐vessel vasodilation and vasoconstriction.3 Endothelial function can be assessed by various techniques, including flow‐mediated vasodilation, carotid intima‐medial thickness and through measurement of serum biomarkers. Another potential assessment target discovered in recent years is the endothelial glycocalyx (EG), increasingly recognized as a novel biomarker of vascular damage. In vascular disease, both risk and event rates have been shown to correlate with measures of the EG5 which is affected at different stages of CKD, including haemodialysis and transplant.7 Some studies have also linked it with microalbuminuria.10 Here, we outline the structure of the EG and current available methods of its assessment. We discuss its potential as a marker of endothelial health and vascular disease, and whether glycocalyx studies performed in kidney disease and microalbuminuria can be correlated with endothelial dysfunction. We also provide a brief overview of therapeutic strategies for EG preservation.