Chondroitin Sulfate C Research Articles

Plasmodium falciparum domain mediating adhesion to chondroitin sulfate A: a receptor for human placental infection.

Malaria during the first pregnancy causes a high rate of fetal and neonatal death. The decreasing susceptibility during subsequent pregnancies correlates with acquisition of antibodies that block binding of infected red cells to chondroitin sulfate A (CSA), a receptor for parasites in the placenta. Here we identify a domain within a particular Plasmodium falciparum erythrocyte membrane protein 1 that binds CSA. We cloned a var gene expressed in CSA-binding parasitized red blood cells (PRBCs). The gene had eight receptor-like domains, each of which was expressed on the surface of Chinese hamster ovary cells and was tested for CSA binding. CSA linked to biotin used as a probe demonstrated that two Duffy-binding-like (DBL) domains (DBL3 and DBL7) bound CSA. DBL7, but not DBL3, also bound chondroitin sulfate C (CSC) linked to biotin, a negatively charged sugar that does not support PRBC adhesion. Furthermore, CSA, but not CSC, blocked the interaction with DBL3; both CSA and CSC blocked binding to DBL7. Thus, only the DBL3 domain displays the same binding specificity as PRBCs. Because protective antibodies present after pregnancy block binding to CSA of parasites from different parts of the world, DBL-3, although variant, may induce cross-reactive immunity that will protect pregnant women and their fetuses.

Lysine 58 and Histidine 66 at the C-terminal α-Helix of Monocyte Chemoattractant Protein-1 Are Essential for Glycosaminoglycan Binding

Monocytes rolling on the endothelial cell layer interact with monocyte chemoattractant protein-1 (MCP-1) that is tethered to the proteoglycans on the luminal side of the endothelial cells and consequently initiate adhesion of monocytes in the early phase of immune response. The amino acid residues in MCP-1 involved in tethering to the proteoglycans have not been elucidated. MCP-1 showed binding to [3H]heparin with a KD of 1.5 microM. We substituted lysine or histidine residues at the C-terminal end of MCP-1 with alanine residues and tested these mutants for their ability to bind heparin, heparan sulfate, hyaluronic acid, and chondroitin sulfate-C. Substitution of Lys-58 or His-66 drastically reduced glycosaminoglycan binding. Substitution of Lys-56 or deletion of the five amino acid residues at the C terminus, including Lys-75, did not alter the heparin binding ability, suggesting that the other lysine residues at the C terminus are not involved in glycosaminoglycan binding. MCP-1 and its mutants did not bind hyaluronic acid as strongly as the other subunits of the GAGs. Substitution of Lys-58 or His-66 by alanine that prevented glycosaminoglycan binding did not affect Ca2+ influx, receptor binding, or chemotactic activity elicited by the chemokine on monocytic THP-1 cells. Therefore, we conclude that the Lys-58 and His-66 residues in the C-terminal alpha-helix of MCP-1 are essential for glycosaminoglycan binding and probably for the binding to the endothelial surface proteoglycans.

Nitric Oxide Products Degrade Chondroitin Sulfates

Nitric oxide (NO) is a potent endogenous vasodilator that is elevated in response to inflammation. Inflammation also produces high levels of superoxide, which combines with NO to produce peroxynitrite (PN). We have previously reported that NO degrades heparin and heparan sulfate under acidic conditions and that PN degrades hyaluronan (HA) at neutral pH. Heparin and HA are glycosaminoglycans (GAGs) widely distributed in the extracellular matrix of tissues. Disruption of intestinal GAGs, particularly the chondroitin sulfates, were linked to inflammatory bowel diseases. Chondroitin sulfate A (CSA), chondroitin sulfate B (CSB), and chondroitin sulfate C (CSC) are constituents of the basement membranes of many tissues, including the intestine. The purpose of this study is to determine whether the NO donorS-nitroso-N-acetylpenicillamine (SNAP) and PN can degrade chondroitin sulfatesin vitro.The NO donor SNAP (2 mM, pH 4.0) or PN (5 mM, pH 7.4) was incubated for at least 1 week at 37°C with CSA, CSB, or CSC. Breakdown of CSA, CSB, and CSC was assessed by gel filtration chromatography and compared with untreated controls. Percentage degradation was calculated based on the change in peak height compared to the control. SNAP treatment partially degraded CSB and CSC, whereas PN partially degraded all three chondroitin sulfates. Nitric oxide mediated degradation of GAGs, and particularly chondroitin sulfates, may be an important pathway of inflammatory tissue damage.

Ion chromatography of anions on stationary phases modified with chondroitin sulfate

Inorganic anions were separated on anion exchangers modified with chondroitin sulfate-C. Retention of anions was not significantly affected by the eluent concentration for the TSKgel IC-Anion-SW anion exchanger modified with chondroitin sulfate-C. Lower concentrations of eluent could be used as the eluent. The system was applied to the determination of UV-absorbing anions in saliva.

Purification and properties of a novel glycosaminoglycan depolymerase from Streptococcus intermedius strain UNS 35

A glycosaminoglycan (GAG) depolymerase that acts on chondroitin sulphate A (CS-A), chondroitin sulphate C (CS-C) and hyaluronic acid (HA) was purified to apparent homogeneity from a culture of Streptococcus intermedius, strain UNS 35, grown in minimal medium supplemented with CS-A as the sole carbon source. The enzyme was purified by ammonium sulphate precipitation followed by serial chromatography on DEAE Trisacryl M, CM Trisacryl M and heparin-agarose. SDS-PAGE analysis of the purified enzyme yielded a single band with a mol.wt of c. 83000. The purified GAG depolymerase was unusual in its substrate specificity. The enzyme was initially regarded as a CS depolymerase because of its induction by CS-A. However, the GAG depolymerase exhibited greatest activity against HA, whereas the degradation rates of CS-A and CS-C were c. 8% and 2%, respectively, of the rate with HA. On this basis the enzyme could be classified as a hyaluronidase rather than a CS depolymerase. The pH optimum was around neutrality and the enzyme was unusual in having a high pI of approximately 9.3.

Energy transfer and formation of exciplex between thiacyanine and acridine orange facilitated by anionic biopolymers and synthetic polymers

The fluorescence of thiacyanine (THIA) dye is greatly enhanced on binding to polyanions due to the reduction in internal conversion of the excitation energy of the dye. Glycosaminoglycans (chondroitin sulphates (CS) A, B and C; heparin) and the synthetic polyanion poly(vinylsulphate) (PVS), in addition to enhancing the fluorescence of THIA, facilitate the formation of an exciplex between excited THIA and cool acridine orange (AO), both bound to the polymers. Of the three chondroitin sulphates, chondroitin sulphate C (CSC) is the most efficient in enhancing the fluorescence of THIA and facilitating the formation of an exciplex. The efficiency of heparin in this respect is comparable with that of CSC,and poly(vinyl sulphate) is even more efficient. In 20% (v/v) ethanol the association constant of THIA—CSC is reduced to one-tenth of its value in water. Aqueous ethanol also partially inhibits exciplex formation between the two dyes bound to chondroitin sulphates, although the effect is less prominent in the case of CSC.

A clinical, electrophysiological, morphological and immunological study of chronic sensory neuropathy with ataxia and paraesthesia.

We have observed 9 patients (8 men and 1 woman), 58 to 77 years of age with neuropathy with only sensory symptoms and insidious onset. Five of them (4 men and 1 woman) aged 65 to 77 years, had normal serum electrophoretic profiles, while the others (all men), 58 to 74 years, had IgM monoclonal gammopathy of undetermined significance (MGUS). Clinical data were consistent with a sensory neuropathy affecting predominantly the kinesthetic sense (position and vibration sensation). The electrophysiological data indicated predominant sensory axonal neuropathy. Morphological data confirmed the primary axonal damage. Western immunoblot showed that the IgG from a patient without MGUS reacted with a 55 kD protein of dorsal root ganglion homogenate. Three of four patients with IgM MGUS were serum reactive against chondroitin sulfate C (ChS-C) in double immunodiffusion. After absorption with ChS-C the monoclonal peak completely disappeared from two patients and was decreased in the third patient. Our data indicate that immunological abnormalities are part of the pathogenesis for a subgroup of chronic neuropathy with only sensory symptoms.

Polyelectrolyte complexes of glycol chitosan with some mucopolysaccharides: Dielectric properties and electrical conductivity

AbstractThe dielectric properties, DC electrical conductivity, and I‐V characteristics of thin films of polyelectrolyte complexes formed by glycol chitosan (GlChi) with mucopolysaccharides chondroitin sulfate A (CSA), chondroitin sulfate C (CSC), and hyaluronic acid (HA) have been studied at different temperatures. The dielectric constant and the loss factor were measured at frequencies ranging from 1 to 100 kHz at all temperatures. The behavior of GlChi–CSA and GlChi–CSC complexes resembles that of the GlChi–dextran sulfate complex reported earlier. The GlChi–HA complex behaves differently and is similar to the GlChi–alginic acid complex reported [Srinivasan, R. & Kamalam, R. (1982) Biopolymers 21, 251–263, 265–275].

The effect of pH and ionic strength on the electrophoretic separation of acidic glycosaminoglycans

Using the electrophoretical methods applied to this study it is possible to determinate the dissociation constants (p K) of acid glycosaminoglycans containing a carboxylic group. The p K-values of the six acid glycosaminoglycans separated from animal connective tissues determined in this work were: hyaluronic acid (HA), p K = 3.0; chondroitin sulfate A (CS-A), p K = 2.8; chondroitin sulfate C (CS-C), p K = 3.3; dermatan sulfate (CS-B), p K = 3.3; heparatin sulfate (HeS), p K = 3.1 and heparin (HeP), p K = 2.4 and were measured at a constant ionic strength of I = 0.164 (NaCl) and at 10 ± 2°C. Variation of ionic strength showed that physiological conditions seem to be most suitable for the electrophoretic separation of the glycosaminoglycans studied. A decrease of ionic strength causes increasing mobility but less accurate spots. In the case of increasing ionic strength the results are vice versa. The second spot for HA very often appeared when pH values higher than 2 were used for electrophoresis. The spot had the same form as the original, high intensity, but an undecided migration in the pH range near the p K value of HA (3.0).

Glycosaminoglycan—Lipoprotein complexes from aortas of hypercholesterolemic rabbits: Part 1. Isolation and characterization

Glycosaminoglycan—lipoprotein complexes were isolated from rabbit aortas exhibiting nearly confluent cholesterol-induced foam cell lesions by extraction with 0.15 M NaCl. Purification and characterization was achieved by gel chromatography, non-ionic differential flotation and by cellulose polyacetate electrophoresis. Analysis showed that these complexes consisted of very low density lipoproteins, heparan sulfate, chondroitin sulfate-C and hyaluronic acid. The demonstration that rabbit intimal foam cell lesions contain extractable glycosaminoglycan—lipoprotein complexes makes this animal model an excellent tool for further studies on the role of these complexes in the atherogenic process.

Studies on anti-atherosclerotic agents. VII. Experimental studies of sodium chondroitin polysulfate on hypolipemic, anticoagulative, fibrinolytic and lipotropic activities

Biological activities were examined on sodium chondroitin polysulfate of low molecular weight, which was obtained from natural chondroitin sulfate-C. Some of them demon-strated lipemia-clearing and anticoagulative activities which were examined in hyperlipemic mice and intact rats, respectively. Sodium chondroitin polysulfate (molecular weight, 4000-6000 ; sulfur content, 13-16%) (CPS) has been selected as having the lowest molecular size with high biological activity. Following results were obtained from pharmacological examinations in view of the antiatherosclerotic activity. 1) Oral Treatment : Hypotriglyceridemia associated with activation of lipopretein lipase was observed acutely in intact and hyperlipemic rats. After a 6-month succesive administation, hypotriglyceridemia was recognized, while normal blood coagulation was observed in intact rats treated with CPS. 2) Intraperitoneal Treatment : Fibrinolytic activity, determined by the time of lysis of euglobulin, is elevated in rats treated with CPS. Further, lipotropic activity of CPS was observed from the experiments on CCl4-induced injury of rat liver. From these results, characteristic feature of CPS was also discussed with respect to the antiatherosclerotic properties.

Distribution and composition of acid mucopolysaccharides in normal and atherosclerotic human aortas

The relationship between tissue concentration and composition of the acid mucopolysaccharides (acid MPS) of the human aorta and the stage of atherosclerosis and/or age has been examined. Acid MPS have been analysed in the intima, the media, and excised atherosclerotic lesions from aortas at different stages of atherosclerosis. The analyses comprised the determination of the total acid MPS; the acid MPS that are digestible by testicular hyaluronidase, i.e. hyaluronic acid (HA) plus chondroitin sulphate C (CSA-C); the hyaluronidase-resistant MPS, i.e. heparitin sulphate (HS) plus chondroitin sulphate B (CSA-B), and the four components separately. The concentrations of total acid MPS (per dry defatted weight) vary according to kind of tissue and lesions, but show little correlation with the stage of atherosclerosis. The concentrations of resistant acid MPS are highest in the fatty streaks and spots and lowest in the ulcerated lesions. The concentration of HA decreases with increasing stage of atherosclerosis and/or ageing; that of HS shows a maximum at stage I; that of CSA-C is maximal at II; no correlation was found between CSA-B concentration and stage of the disease. A decreased permeability of the arterial wall and a decreased fibrinolytic activity consequent upon these changes in MPS composition are seen as possible factors in the development of atherosclerotic plaques.

PROTEIN-POLYSACCHARIDE COMPLEXES OF NORMAL AND HERNIATED HUMAN INTERVERTEBRAL DISCS.

SummaryA protein-polysaccharide complex containing a 1:1 ratio of chondroitin sulfate-C and keratosulfate has been found in both nucleus pulposus and annulus fibro-sus of human intervertebral discs. The limiting viscosity number of this complex decreases gradually with age in normal subjects. Complex prepared from herniated discs has a much lower limiting viscosity number than normal. An insoluble complex having considerable amounts of chondroitin sulfate-B has been found in normal aged discs and in all herniated discs.