Biological functions of iduronic acid in chondroitin/dermatan sulfate

Abstract

The presence of iduronic acid in chondroitin/dermatan sulfate changes the properties of the polysaccharides because it generates a more flexible chain with increased binding potentials. Iduronic acid in chondroitin/dermatan sulfate influences multiple cellular properties, such as migration, proliferation, differentiation, angiogenesis and the regulation of cytokine/growth factor activities. Under pathological conditions such as wound healing, inflammation and cancer, iduronic acid has diverse regulatory functions. Iduronic acid is formed by two epimerases (i.e. dermatan sulfate epimerase 1 and 2) that have different tissue distribution and properties. The role of iduronic acid in chondroitin/dermatan sulfate is highlighted by the vast changes in connective tissue features in patients with a new type of Ehler–Danlos syndrome: adducted thumb-clubfoot syndrome. Future research aims to understand the roles of the two epimerases and their interplay with the sulfotransferases involved in chondroitin sulfate/dermatan sulfate biosynthesis. Furthermore, a better definition of chondroitin/dermatan sulfate functions using different knockout models is needed. In this review, we focus on the two enzymes responsible for iduronic acid formation, as well as the role of iduronic acid in health and disease.

Identification of Chondroitin Sulfate Linkage Region Glycopeptides Reveals Prohormones as a Novel Class of Proteoglycans

“…However, for CS the biosynthesis continues with the addition of an N-acetylgalactosamine (GalNAc␤3), whereas HS biosynthesis continues with the addition of an N-acetylglucosamine (GlcNAc␣4) (6). The CS-chains are thereafter elongated through the addition of repeating units of GlcA and GalNAc and are further modified by the addition of specifically positioned sulfate groups (7). Certain features of the core protein seem to influence if a certain Ser residue is selected for GAG attachment and whether CS or HS will be synthesized, but the selection mechanism is largely unknown.…”

Holistic and dynamic metabolic alterations of traditional Chinese medicine syndrome in a toxic heat and blood stasis syndrome rat model

“…Then 6 mL blood obtained with the heart puncture technique was collected into one 2 mL sodium citrate vacuum blood collection tube (SCVBCT) and two 2 mL EDTA vacuum blood collection tubes (EVBCTs). The blood sample in one of the EVBCTs stood at room temperature (22)(23)(24)(25) C) for 30 min. The blood samples in the SCVBCT and the other EVBCT were centrifuged at 3000 rpm for 10 min to get the plasma and stored at À80 C until the biochemical analysis.…”

“…Prior to UPLC-MS analysis, the urine samples were thawed at room temperature (22)(23)(24)(25) C), diluted at a ratio of 2 : 1 (v/v) using ultra high purity water, vortex mixed and centrifuged at 14 000 rpm for 10 min at 4 C.…”

Composition and significance of glycosaminoglycans in the uterus and placenta of mammals

“…The molecules act on cell recognition, migration, adhesion, proliferation and differentiation of the cells. In fact, it is directly or indirectly linked to the onset of tumors and metastases, in angiogenesis, in immunological reactions, in the development of follicles and in infertility (Dietrich 1984;Nasciutti et al 2006;Li and Spillmann 2012;Malmström et al 2012;Thelin et al 2013). Due to their anionic features, GAGs are also involved in cation links (sodium, potassium and calcium, for instance) and in the retention of water in the tissues.…”