Hyaluronan: its nature, distribution, functions and turnover

Abstract

Fraser JRE, Laurent TC, Laurent UBG (Monash University, Clayton, Victoria, Australia; and University of Uppsala, Uppsala, Sweden). Hyaluronan: its nature, distribution, functions and turnover (Minisymposium: Hyaluronan). J Intern Med 1997; 242: 27–33. Hyaluronan is a polysaccharide found in all tissues and body fluids of vertebrates as well as in some bacteria. It is a linear polymer of exceptional molecular weight, especially abundant in loose connective tissue. Hyaluronan is synthesized in the cellular plasma membrane. It exists as a pool associated with the cell surface, another bound to other matrix components, and a largely mobile pool. A number of proteins, the hyaladherins, specifically recognize the hyaluronan structure. Interactions of this kind bind hyaluronan with proteoglycans to stabilize the structure of the matrix, and with cell surfaces to modify cell behaviour. Because of the striking physicochemical properties of hyaluronan solutions, various physiological functions have been assigned to it, including lubrication, water homeostasis, filtering effects and regulation of plasma protein distribution. In animals and man, the half‐life of hyaluronan in tissues ranges from less than 1 to several days. It is catabolized by receptor‐mediated endocytosis and lysosomal degradation either locally or after transport by lymph to lymph nodes which degrade much of it. The remainder enters the general circulation and is removed from blood, with a half‐life of 2–5 min, mainly by the endothelial cells of the liver sinuoids.

Boundary lubrication of articular cartilage: Role of synovial fluid constituents

“…SF is composed of HA ranging from 2,000 kd to 10,000 kd (30,44), PRG4 proteins ranging from ϳ14 kd to ϳ345 kd (4,45), and SAPL of different types with DPPC being a major form (33). HA has been shown to lubricate at a cartilage-cartilage interface on a joint scale equally well at 1,030 kd and 1,930 kd (14), and certain other properties of HA do not depend on molecular weight either (in the range of 500-6,000 kd) (46).…”

Serum laminin, type IV collagen and hyaluronan as fibrosis markers in non-alcoholic fatty liver disease

“…Among the extracellular matrix components, we selected for this study those with the highest correlation with parenchymatous and perisinusoidal fibrosis as it occurs in NAFLD (31)(32)(33). LM is the largest protein of the basement membrane and in chronic liver diseases it is progressively deposited along Disse's space accompanying sinusoid capillarization (34,35).…”

“…HA is a non-sulfated glycosaminoglycan synthesized in the liver by stellate cells. Its serum concentration significantly increases in chronic diseases of the liver of different etiologies, due not only to a greater hepatic production but also to a decrease in its degradation by endothelial liver cells (33,38). In these patients, especially those with disease of viral and alcoholic etiology, increased levels of this glycosaminoglycan have been detected and were shown to be related to the degree of fibrosis in liver tissue (38,39).…”

Serum hyaluronan and collagen IV as non-invasive markers of liver fibrosis in patients from an endemic area for schistosomiasis mansoni: a field-based study in Brazil

“…The ultrasound variables included were as follows: left and right liver lobe length, spleen length, portal, splenic and superior mesenteric vein diameters, periportal fibrosis (subjective evaluation), WHO patterns of fibrosis, gallbladder wall thickness, periportal thickness in the hilum and on first and second order branches. Data was also adjusted by age and body mass index (BMI), based on literature evidence of HA variations with aging and nonalcoholic steatohepatitis (Fraser et al 1997, Sakugawa et al 2005, Suzuki et al 2005.…”