Background & aims: In liver cirrhosis, the binding and degradation of hyaluronic acid in the hepatic sinusoidal endothelial cells are considered to be reduced by development of hepatic sinusoidal capillarization, resulting in high serum hyaluronic acid concentration. The aim of this study is to clarify the cause of high blood hyaluronic acid concentration in liver cirrhosis.
Methods: Liver cirrhosis was induced in rats by thioacetamide administration. In vivo observation of sinusoidal capillarization, in vitro immunolocalization of factor VIII-related antigen and CD44, and [14C]hyaluronic acid binding in cultured sinusoidal endothelial cells were determined.
Results: Basement membranes were observed on the basal side of sinusoidal endothelial cells. The fenestrae and fluorescent intensity of anti-CD44 bound to the cells decreased with progression of hepatic fibrosis. Immunofluorescent reactive products of factor VIII-related antigen were more abundant in the cirrhotic rats compared with the controls. Amount of [14C]hyaluronic acid binding was significantly decreased in the cirrhotic group compared with the controls.
Conclusions: One reason that the blood hyaluronic acid concentration increases markedly in liver cirrhosis is considered to be the reduction in hyaluronic acid receptors of hepatic sinusoidal endothelial cells and in the amount of hyaluronic acid binding to the cells.