Glycocalyx Cleavage Boosts Erythrocytes Aggregation

TL;DR

This study demonstrates that enzymatic degradation of the erythrocyte glycocalyx significantly increases cell aggregation, potentially impacting microcirculatory blood flow and cardiovascular health.

Contribution

It provides new experimental evidence linking glycocalyx impairment to increased erythrocyte aggregation and altered aggregate morphology.

Findings

Amylase incubation increases erythrocyte aggregation.

Glycocalyx degradation correlates with enhanced aggregation.

Altered aggregate morphology observed under microscopy.

Abstract

The glycocalyx is a complex layer of carbohydrate and protein molecules that surrounds the cell membrane of many types of mammalian cells. It serves several important functions, including cell adhesion and communication, and maintain cell shape and stability, especially in the case of erythrocytes. Alteration of glycocalyx composition represents a cardiovascular health threatening. For example, in diabetes mellitus glycocalyx of erythrocytes and of endothelial cells is known to be impaired, a potential source of blood occlusion in microcirculation, which may lead to blindness, and renal failure of patients. The impact of glycocalyx impairment on erythrocyte aggregation remains a largely unexplored research area. We conduct here in vitro-experiments in microfluidic devices in order to investigate erythrocytes aggregation incubated with amylase, an enzyme that partially breaks down glycocalyx molecules. It is found that incubation of erythrocytes by amylase leads to a dramatic increase of their aggregation and stability and alters the aggregates morphologies. Confocal microscopy analysis reveals a significant degradation of the glycocalyx layer, correlated with enhanced erythrocytes aggregation. An increased erythrocyte aggregation in vivo should affect oxygen and other metabolites delivery to organs and tissues. This study brings new elements about elucidation of microscopic origins of erythrocyte aggregation and their potential impact on cardiovascular pathologies.