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Effects of glucosamine hydrochloride on the production of prostaglandin E2, nitric oxide and metalloproteases by chondrocytes and synoviocytes in osteoarthritis.

OBJECTIVES: To determine the response of glucosamine hydrochloride on chondrocytes and synoviocytes in terms of prostaglandin E2 (PGE2), nitric oxide (NO) and matrix metalloproteases (MMPs). METHODS: Chondrocytes and synoviocytes were prepared from joint specimens of patients who underwent total knee arthroplasty for osteoarthritis (OA). Chondrocytes from patients with femoral neck fracture were served as a normal control. Culture cells were stimulated by 5 ng/ml of IL-1beta and treated with various concentration of glucosamine hydrochloride (from 1 microg/ml to 500 microg/ml). PGE2, NO, MMP-1, MMP-3, and MMP-13 levels were evaluated in the culture supernatant. Further, the expression of COX-2 mRNA was studied by semiquantitative PCR. RESULTS: With IL-1beta stimulation, the levels of these mediators increased dramatically, except for NO from synoviocytes. After stimulation, levels of these mediators in OA chondrocytes were higher than synoviocytes and normal chondrocytes, and the level of MMP-3 was higher than those of MMP-1 and MMP-13. Glucosamine hydrochloride at a concentration of 100 microg/ml suppressed PGE2 production, and partly suppressed NO production. It also suppressed the production of MMPs from normal chondrocytes and synoviocytes but not from OA chondrocytes. CONCLUSION: Glucosamine modulates the metabolism of chondrocytes and synoviocytes and its mode of action differs between cells and conditions.

Aged↗

Precolumn derivatization liquid chromatography method for analysis of dietary supplements for glucosamine: single laboratory validation study.

A precolumn derivatization liquid chromatography (LC) method was developed for the analysis of various dietary supplement formulations and raw materials for glucosamine. A 1 mL sample or standard water solution (containing about 0.05 mg glucosamine) was mixed with 1 mL pH 8.3 buffer, 1 mL 5% phenylisothiocyanate methanolic solution, and derivatized at 80 degrees C in a water bath for 30 min. After derivatization, the solution was cooled in a cold water bath and centrifuged at 3000-5000 rpm. The clear upper layer was ready for injection. The LC system was equipped with a C18 reversed-phase column and an ultraviolet detector set at 240 nm. The column was developed with a linear gradient composed of 0.1% phosphoric acid in deionized water and 0.1% phosphoric acid in methanol. The method was subjected to Single Laboratory Validation. The method precision was 0.50% relative standard deviation, accuracy was less than +/-1.5%, method linearity in the range 0-2 mg glucosamine/mL was 1.00, the detection limit was 0.0705 microg/mL, and the quantitation limit was 0.235 microg/mL. Chondroitin sulfate, amino acids, and excipients did not interfere with glucosamine testing. After derivatization, both standard and sample preparations were stable for at least 48 h. Due to its high sensitivity, this method can be used to assay glucosamine in functional foods and pet foods. The validation data will be published separately.

Chromatography, Liquid↗

[A multi-central, randomized, controlled clinical trial of glucosamine hydrochloride/sulfate in the treatment of knee osteoarthritis].

OBJECTIVE: To evaluate the efficacy and safety of glucosamine hydrochloride (GH) in the treatment of patients with knee osteoarthritis (OA) comparing with glucosamine sulfate (GS). METHODS: A multi-central, randomized, parallel-controlled clinical trial of GH vs GS was performed. 142 patients suffering from knee OA were randomized into 2 groups, treated with GH and GS for 480 mg and 500 mg one time respectively. Patients received medicine 3 times daily with total 1440 mg per day for GH group and 1500 mg for GS group, orally for 4 weeks and were assessed for drug efficacy and safety for 2 more weeks. Knee pain at rest, at movement and at pressure, knee swelling, morning stiffness and walking ability were recorded at 1, 2, 3, 4 and 6 week according to Lequesne's criteria. Other features such as therapeutic efficacy, adverse events and laboratory parameters were also recorded. RESULTS: A considerable improvement in OA symptoms and a reduce of total Lequesne's score were observed in both groups after the 4-week treatment. The Lequesne's score decreased to 3.4 +/- 1.9 (P < 0.05) and 3.4 +/- 1.8 (P < 0.05) after 4-week treatment comparing to 0-week in the GH (9.4 +/- 1.8) group and GS (9.5 +/- 1.4) group respectively. There was no significant difference between 2 groups in decreasing the Lequesne's score (P > 0.05). The symptomatic improvement rates in patients were 91.4% and 90.0% at 4-week treatment in the GH and GS group respectively (P > 0.05). There was a remnant therapeutic effect in both groups at 2 weeks after discontinuation of the treatment. And 4.2% (3/71) of patients on GH reported adverse events, vs 7.0% (5/71) adverse events with GS group (P > 0.05), mainly mild stomach discomfort and constipation. CONCLUSION: There were no significant differences in efficacy and safety between GH and GS groups in the treatment of knee OA. Glucosamine hydrochloride is as effective and safe as glucosamine sulfate.

Administration, Oral↗

[The efficacy of glucosamine in treating complicated hyperreactive experimental myocardial infarct].

The effect of glucosamine hydrochloride on the course of complicated hyperreactive myocardial infarction in dogs was studied. Glucosamine contributed to the restoration of reactivity in the animals. The reactivity became corresponding for normoreactive myocardial infarction. Glucosamine normalized carbohydrate and protein metabolism in the necrosis zone, cAMP and cGMP and also their ratio that led to healing by postinfarction scar, and in none of the cases the heart aneurysm developed. The optimizing healing of hyperreactive myocardial infarction under the influence of glucosamine is mediated through the mechanisms of reactivity and the regulation of metabolic processes.

Adrenocorticotropic Hormone↗

[Therapy of interstitial and radiogenic cystitis with D-glucosamine].

Twelve patients with interstitial or radiation cystitis were treated by D-glucosamine, a precursor of glycosaminoglycans. D-glucosamine was given for 3 months (500 mg t.i.d. orally). Urinary glycosaminoglycans which were low before the treatment could be increased significantly by D-glucosamine. Endoscopic findings and subjective symptoms could be markedly improved. D-glucosamine may be a new treatment modality in interstitial and radiation cystitis.

Administration, Oral↗

Effect of N-phosphonacetyl-L-aspartate and D-glucosamine on the incorporation of 5-fluorouridine into normal tissues and an adenocarcinoma in the rat.

Cytostatic treatment of liver metastases from colorectal cancer has been of limited value. Higher drug levels in the target substances of the tumor may improve the results. It was the aim of this investigation to examine the effect of PALA (N-phosphonacetyl-L-aspartate) and D-glucosamine on the level of uracil nucleotides in the liver and in an N-methyl-N-nitrosoguanidine-induced adenocarcinoma of the colon transplanted to the liver of rats, and on the incorporation of 3H-FUrd into the acid-soluble fraction, the RNA and the DNA of the tumor and of several normal tissues. Combined treatment with PALA and D-glucosamine reduced the UTP pool in the liver and the tumor. D-glucosamine alone increased UDP-N-acetyl-hexosamine in liver tissue. Pretreatment with PALA and D-glucosamine increased incorporation of 3H-FUrd into RNA of the liver and kidney, and into the DNA fraction of the liver, but had no effect on 3H-FUrd incorporation in the tumor.

Adenocarcinoma↗

Metabolism and biological activity of a thiamine new salt. I. Urinary excretion and tissue content of vitamin B1 in rats treated with thiamine chloride ester monophosphate of Bis-glucosamine.

Research has been carried out on the metabolism of thiamine chloride ester monophosphate of bis-D-glucosamine (TCMPG) evaluating the urinary excretion, the blood and the hepatic content of thiamine in the rat after intraperitoneal injection of this compound. The results obtained have shown a greater retention of vitamin B1 when it is administered as glucosamine salt. In fact, the amount of thiamine excreted by the rats which have received the TCMPG is lower while the blood and liver levels of vitamin are higher, compared with the control rats treated with thiamine monophosphate only, or with thiamine and glucosamine. These results permit the conclusion that glucosamine increases the utilization of the vitamin and its penetration into the cells.

Animals↗

Oral glucosamine sulphate in the management of arthrosis: report on a multi-centre open investigation in Portugal.

An open study was carried out by 252 doctors throughout Portugal to assess the effectiveness and tolerability of oral glucosamine sulphate in the treatment of arthrosis. Patients received 1.5 g daily in 3 divided doses over a mean period of 50 +/- 14 days. The results from 1208 patients were analyzed and showed that the symptoms of pain at rest, on standing and on exercise and limited active and passive movements improved steadily through the treatment period. The improvement obtained lasted for a period of 6 to 12 weeks after the end of treatment. Objective therapeutic efficacy was rated by the doctors as 'good' in 59% of patients, and 'sufficient' in a further 36%. These results were significantly better than those obtained with previous treatments (except for injectable glucosamine) in the same patients. Sex, age, localization of arthrosis, concomitant illnesses or concomitant treatments did not influence the frequency of responders to treatment. Oral glucosamine was fully tolerated by 86% of patients, a significantly larger proportion than that reported with other previous treatments and approached only by injectable glucosamine. The onset of possible side-effects was significantly related to pre-existing gastro-intestinal disorders and related treatments, and to concomitant diuretic treatment.

Arthritis↗

[3H]glucosamine and [3H]proline radioautography of embryonic mouse dental basement membrane.

[3H]proline and [3H]glucosamine radioautography was performed to analyze the labeling pattern of mouse embryonic dental basement membrane before and during odontoblast terminal differentiation. Sixteen- and eighteen-day-old first lower molars and trypsin-isolated enamel organs, as well as EDTA-isolated dental papillae, were used. Continuous labeling for 12 to 24 hr was required with [3H]proline to obtain a clear labeling of epithelial-mesenchymal junction in intact tooth germs or accumulation of surface label in trypsin-isolated enamel organs. With [3H]glucosamine, after 6-hr labeling, the epithelial-mesenchymal junction was heavily labeled and the trypsin-isolated enamel organs accumulated substantial amounts of surface label, corresponding to the redeposited basement membrane. At Day 16 stage, these labels always had a uniform distribution and decreased during chase without any redistribution. At Day 18 stage, when the terminal differentiation of odontoblasts occurred the label accumulated in a unique pattern: much more label was at the epithelial surface corresponding to the top of the cusps than in the apical parts. During chase and only in intact tooth germs epithelial surfaces which had labeled poorly during pulse became labeled, but those labeling heavily during pulse lost label. This pattern existed only in the presence of mesenchyme. EDTA treatment of [3H]glucosamine-labeled teeth enabled us to obtain isolated dental papillae with surface label. Distribution of this label was exactly the same as that for the epithelial-mesenchymal junction of intact teeth. During chase, these dental papillae completely lost the surface label. The mesenchyme seen to control the synthesis and/or the degradation of epithelially derived [3H]glucosamine-labeled material.

Animals↗

Sanfilippo D syndrome: correction of glucosamine-6-sulphatase deficiency following fibroblast culture in Chang's media.

The de-O-sulphation of alpha-linked glucosamine-6-sulphate residues in heparan sulphate requires a specific sulphatase, glucosamine-6-sulphatase, which has been shown to be deficient in tissues of Sanfilippo D, or mucopolysaccharidosis type IIID (MPS IIID), patients. MPS IIID fibroblasts cultured in Basal Eagle's medium supplemented with either fetal calf serum or heat-inactivated fetal calf serum, MDCB or Ultraserg media had residual glucosamine-6-sulphatase activities towards a heparin-derived trisaccharide substrate, O-(alpha-N-acetylglucosamine-6-sulphate)-(1----4)-L-O-(alpha- iduronic acid-2-sulphate)-(1----4)-D-O-2,5-anhydro[1-3H]mannitol-6- sulphate, GlcNAc6S-IdoA2S-anM6S, which were less than 1 per cent of the normal range for fibroblasts cultured in Basal Eagle's medium supplemented with fetal calf serum. However, the glucosamine-6-sulphatase activities of MPS IIID fibroblasts grown in Chang's medium were similar to the activities in normal control fibroblasts which were cultured in Basal Eagle's medium. These results indicate that caution is required for prenatal diagnosis of MPS IIID patients using chorionic villi or amniotic cells cultured in Chang's medium.

Cells, Cultured↗

Detection of glucosamine in the acid hydrolysis solution of humic substances.

Several humic substances isolated from water and soil have been characterized applying acid hydrolysis to release defined components bound in these high molecular organic compounds. The hydrolysis solution have been analyzed by HPLC after precolumn derivatization with o-phthalaldehyde and 9-fluorenylmethylchloroformate. Under these conditions the nitrogen containing carbohydrate glucosamine could be detected and separated besides seventeen amino acids. The results show that 8.0 to 40.1% of the total nitrogen content of the investigated samples contributes to amino acids and up to 7.9% to the carbohydrate glucosamine. It could be deduced that defined amino acid carbohydrate building blocks were bound in humic substances, because the glucosamine nitrogen content correlates with the calculated amino acid nitrogen. Furthermore the total amino acid nitrogen amount of natural organic matter can be estimated from the results of the determination of glucosamine.

Journal Article↗

Sulfhydryl groups of glucosamine-6-phosphate isomerase deaminase from Escherichia coli.

Glucosamine-6-phosphate isomerase deaminase (2-amino-2-deoxy-D-glucose-6-phosphate ketol isomerase (deaminating), EC 5.3.1.10) from Escherichia coli is an hexameric homopolymer that contains five half-cystines per chain. The reaction of the native enzyme with 5',5'-dithiobis-(2-nitrobenzoate) or methyl iodide revealed two reactive SH groups per subunit, whereas a third one reacted only in the presence of denaturants. Two more sulfhydryls appeared when denatured enzyme was treated with dithiothreitol, suggesting the presence of one disulfide bridge per chain. The enzyme having the exposed and reactive SH groups blocked with 5'-thio-2-nitrobenzoate groups was inactive, but the corresponding alkylated derivative was active and retained its homotropic cooperativity toward the substrate, D-glucosamine 6-phosphate, and the allosteric activation by N-acetyl-D-glucosamine 6-phosphate. Studies of SH reactivity in the presence of enzyme ligands showed that a change in the availability of these groups accompanies the allosteric conformational transition. The results obtained show that sulfhydryls are not essential for catalysis or allosteric behavior of glucosamine-6-phosphate deaminase.

Allosteric Regulation↗

Two mammalian glucosamine-6-phosphate deaminases: a structural and genetic study.

Glucosamine-6-phosphate deaminase (EC 3.5.99.6) is an allosteric enzyme that catalyzes the reversible conversion of D-glucosamine-6-phosphate into D-fructose-6-phosphate and ammonium. Here we describe the existence of two mammalian glucosamine-6-phosphate deaminase enzymes. We present the crystallographic structure of one of them, the long human glucosamine-6-phosphate deaminase, at 1.75 A resolution. Crystals belong to the space group P2(1)2(1)2(1) and present a whole hexamer in the asymmetric unit. The active-site lid (residues 162-182) presented significant structural differences among monomers. Interestingly the region with the largest differences, when compared with the Escherichia coli homologue, was found to be close to the active site. These structural differences can be related to the kinetic and allosteric properties of both mammalian enzymes.

Aldose-Ketose Isomerases↗

Endoscopic injection of bleeding esophageal varices with a poly-N-acetyl glucosamine gel formulation in the canine portal hypertension model.

BACKGROUND: It has been shown that poly-N-acetyl glucosamine produces rapid hemostasis by stimulating erythrocyte aggregation. Endoscopic injection of this substance may be effective in the treatment of bleeding varices. METHODS: In eight heparinized dogs with a bleeding esophageal varix greater than 2 mm in diameter, 2.5% to 3.5% poly-N-acetyl glucosamine gel was injected intravariceally and paravariceally. Endoscopy, endosonography, and histopathology were performed at 1, 7, 21, and 90 days after injection. RESULTS: In all cases, the variceal hemorrhage was stopped with three to four injections of a mean total gel volume of 1.9 mL. No recurrence of bleeding, ulceration, or stricture formation occurred. Through replacement of the gel by connective tissue, the varix was permanently obliterated in its whole course in five cases and in more than 70% of its length in three cases. No embolization and no poly-N-acetyl glucosamine antibodies were detected. CONCLUSIONS: Endoscopic injection of bleeding esophageal varices in this animal model with the use of poly-N-acetyl glucosamine gel was an effective and safe method for stopping the hemorrhage and inducing permanent varix obliteration.

Acetylglucosamine↗

N-Acetyl-D-glucosamine-specific lectin from the ascidian Didemnum ternatanum.

We report the characterization of the affinity chromatography-purified N-acetyl-d-glucosamine-specific lectin from the ascidian Didemnum ternatanum (DTL). Native molecular weight of lectin estimated by gel filtration was 28 000. The hemagglutinating activity of DTL independent of divalent cations Ca2+ and Mg2+. Significant activity was observed between pH 6-10. In hemagglutination inhibition assays among the mono- and oligosaccharides tested, N-acetyl-d-glucosamine, N, N'-diacetylchitobiose, N,N'N"-triacetylchitotriose were the most potent inhibitors. They showed similar inhibitory activity. Hapten inhibition with various sugars indicated that DTL requires the presence of hydroxyl groups at the C-3 and C-4 of N-acetyl-d-glucosamine. The presence of the hydrophobic p-nitrophenyl aglycone significantly enhanced inhibitory power of N-acetyl-d-glucosamine. On the other hand among the glycoproteins ovomucoid and ovalbumin were the best inhibitors. The interaction of DTL with specific saccharides was investigated by UV difference spectroscopy and association constants were obtained. CD analysis of DTL suggested 4% alpha-helix, 57% beta-sheet, 24% beta-turn and 15% unorder.

Acetylglucosamine↗

The human glucosamine-6-phosphate deaminase gene: cDNA cloning and expression, genomic organization and chromosomal localization.

When mammalian eggs are fertilized by sperm, a distinct series of calcium oscillations are generated which serve as the essential trigger for egg activation and early embryo development. The identification of a soluble hamster sperm 33-kDa protein that co-migrated with calcium oscillation-inducing activity was recently described by Parrington et al. (Parrington, J., Swann, K., Shevchenko, V.I., Sesay, A.K. and Lai, F.A., 1996. Calcium oscillations in mammalian eggs triggered by a soluble sperm protein. Nature 379, 364-368). The hamster sperm 33 kDa protein was termed oscillin because it correlated with calcium oscillation-inducing activity in mammalian eggs. Sequence analysis of the hamster sperm 33 kDa protein indicated no similarity to any known cell signalling molecule, however, it displayed extensive homology with a bacterial glucosamine-6-phosphate deaminase. We have isolated the corresponding human testis homologue of the hamster sperm 33 kDa cDNA. Nucleotide sequence analysis reveals a high level of sequence identity between the hamster and human genes. The deduced protein sequence of the human gene also shares extensive amino acid identity with the bacterial glucosamine-6-phosphate deaminase enzyme. Heterologous expression of the human testis 33 kDa protein produced a glucosamine-6-phosphate deaminase activity. The genomic structure of the human glucosamine-6-phosphate deaminase has been mapped and the gene was localized by fluorescence in situ hybridization (FISH) to chromosome 5q31.

Aldose-Ketose Isomerases↗

Glucosamine measurement as indirect method for biomass estimation of Cunninghamella elegans grown in solid state cultivation conditions.

Glucosamine measurement has been tested as the indirect method to estimate the biomass produced by Cunninghamella elegans during solid state cultivation (SSC). The independence of this cell constituent content from the age and the conditions of the culture have been verified. The influence of the medium composition, in particular the nature of the carbon source on glucosamine amount is presented. Glucosamine can be considered as a well-adapted biomass indicator, with the necessity to establish for each medium tested a prior correlation between biomass and glucosamine amount. This correlation should be defined in submerged conditions before applying the biomass estimating method in SSC.

Journal Article↗

On the multiple functional roles of the active site histidine in catalysis and allosteric regulation of Escherichia coli glucosamine 6-phosphate deaminase.

The active site of glucosamine-6-phosphate deaminase (EC 3.5.99.6, formerly 5.3.1.10) from Escherichia coli was first characterized on the basis of the crystallographic structure of the enzyme bound to the competitive inhibitor 2-amino-2-deoxy-glucitol 6-phosphate. The structure corresponds to the R allosteric state of the enzyme; it shows the side-chain of His143 in close proximity to the O5 atom of the inhibitor. This arrangement suggests that His143 could have a role in the catalysis of the ring-opening step of glucosamine 6-phosphate whose alpha-anomer is the true substrate. The imidazole group of this active-site histidine contacts the carboxy groups from Glu148 and Asp141, via its Ndelta1 atom [Oliva et al. (1995) Structure 3, 1323-1332]. These interactions change in the T state because the side chain of Glu148 moves toward the allosteric site, leaving at the active site the dyad Asp141-His143 [Horjales et al. (1999) Structure 7, 527-536]. In this research, a dual approach using site-directed mutagenesis and controlled chemical modification of histidine residues has been used to investigate the role of the active-site histidine. Our results support a multifunctional role of His143; in the forward reaction, it is involved in the catalysis of the ring-opening step of the substrate, glucosamine 6-P. In the reverse reaction, the substrate fructose 6-P binds in its open chain, carbonylic form. The role of His143 in the binding of both glucosamine 6-P and reaction intermediates in their extended-chain forms was demonstrated by binding experiments using the reaction intermediate analogue, 2-amino-2-deoxy-D-glucitol 6-phosphate. His143 was also shown to be a critical residue for the conformational coupling between active and allosteric sites. From the pH dependence of the reactivity of the active site histidine to diethyl dicarbonate, we observed a pK(a) change of 1.2 units to the acid side when the enzyme undergoes the allosteric T to R transition during which the side chain of Glu148 moves toward the active site. The kinetic study of the Glu148-Gln mutant deaminase shows that the loss of the carboxy group and its replacement with the corresponding amide modifies the k(cat) versus pH profile of the enzyme, suggesting that the catalytic step requiring the participation of His143 has become rate-limiting. This, in turn, indicates that the interaction Glu148-His143 in the wild-type enzyme in the R state contributes to make the enzyme functional over a wide pH range.

Aldose-Ketose Isomerases↗