TY - JOUR
T1 - The mechanisms and physiological relevance of glycocalyx degradation in hepatic ischemia/reperfusion injury
AU - van Golen, Rowan F.
AU - Reiniers, Megan J.
AU - Vrisekoop, Nienke
AU - Zuurbier, Coert J.
AU - Olthof, Pim B.
AU - van Rheenen, Jacco
AU - van Gulik, Thomas M.
AU - Parsons, Barry J.
AU - Heger, Michal
PY - 2014
Y1 - 2014
N2 - Hepatic ischemia/reperfusion (I/R) injury is an inevitable side effect of major liver surgery that can culminate in liver failure. The bulk of I/R-induced liver injury results from an overproduction of reactive oxygen and nitrogen species (ROS/RNS), which inflict both parenchymal and microcirculatory damage. A structure that is particularly prone to oxidative attack and modification is the glycocalyx (GCX), a meshwork of proteoglycans and glycosaminoglycans (GAGs) that covers the lumenal endothelial surface and safeguards microvascular homeostasis. ROS/RNS-mediated degradation of the GCX may exacerbate I/R injury by, for example, inducing vasoconstriction, facilitating leukocyte adherence, and directly activating innate immune cells. Preliminary experiments revealed that hepatic sinusoids contain a functional GCX that is damaged during murine hepatic I/R and major liver surgery in patients. There are three ROS that mediate GCX degradation: hydroxyl radicals, carbonate radical anions, and hypochlorous acid (HOCl). HOCl converts GAGs in the GCX to GAG chloramides that become site-specific targets for oxidizing and reducing species and are more efficiently fragmented than the parent molecules. In addition to ROS/RNS, the GAG-degrading enzyme heparanase acts at the endothelial surface to shed the GCX. The GCX seems to be degraded during major liver surgery, but the underlying cause remains ill-defined. The relative contribution of the different ROS and RNS intermediates to GCX degradation in vivo, the immunogenic potential of the shed GCX fragments, and the role of heparanase in liver I/R injury all warrant further investigation
AB - Hepatic ischemia/reperfusion (I/R) injury is an inevitable side effect of major liver surgery that can culminate in liver failure. The bulk of I/R-induced liver injury results from an overproduction of reactive oxygen and nitrogen species (ROS/RNS), which inflict both parenchymal and microcirculatory damage. A structure that is particularly prone to oxidative attack and modification is the glycocalyx (GCX), a meshwork of proteoglycans and glycosaminoglycans (GAGs) that covers the lumenal endothelial surface and safeguards microvascular homeostasis. ROS/RNS-mediated degradation of the GCX may exacerbate I/R injury by, for example, inducing vasoconstriction, facilitating leukocyte adherence, and directly activating innate immune cells. Preliminary experiments revealed that hepatic sinusoids contain a functional GCX that is damaged during murine hepatic I/R and major liver surgery in patients. There are three ROS that mediate GCX degradation: hydroxyl radicals, carbonate radical anions, and hypochlorous acid (HOCl). HOCl converts GAGs in the GCX to GAG chloramides that become site-specific targets for oxidizing and reducing species and are more efficiently fragmented than the parent molecules. In addition to ROS/RNS, the GAG-degrading enzyme heparanase acts at the endothelial surface to shed the GCX. The GCX seems to be degraded during major liver surgery, but the underlying cause remains ill-defined. The relative contribution of the different ROS and RNS intermediates to GCX degradation in vivo, the immunogenic potential of the shed GCX fragments, and the role of heparanase in liver I/R injury all warrant further investigation
U2 - https://doi.org/10.1089/ars.2013.5751
DO - https://doi.org/10.1089/ars.2013.5751
M3 - Review article
C2 - 24313895
SN - 1523-0864
VL - 21
SP - 1098
EP - 1118
JO - Antioxidants & redox signaling
JF - Antioxidants & redox signaling
IS - 7
ER -