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PubMed1984

[Therapy of gonarthrosis using chondroprotective substances. Prospective comparative study of glucosamine sulphate and glycosaminoglycan polysulphate].

68 patients with mild or moderate gonarthritis were treated with intra-articular injections of glucosamine sulphate or glycosaminoglycan polysulphate over a period of six weeks. The therapy was successful in two thirds of these patients. "Loading" pain was eliminated or improved in about 80%, "getting-going" pain in about 64%, and signs of synovialitis in about 66%. Gait function and mobility were improved. Glucosamine had a superior effect, in particular in mild arthritis, achieving an improvement of pain in 90%, while glycosaminoglycan polysulphate was successful in advanced cases. The tolerance of the two substances was 94%. The results and the underlying modes of action of the substances are discussed.

Arthritis↗

PubMedDate not supplied

[Rapid effect of glucuronyl glucosamine glycan sulfate on the blood levels of HDL-cholesterol in vascular diseases].

The Authors investigated on the main lipidemic parameters in vascular diseases after acute administration of glucuronyl-glucosamine-glycan sulfate (3GS). The study was carried out in 48 subjects, aged 33 to 78, of whom 38 males and 10 females so divided: 6 metabolically healthy controls (N), 10 with vascular cerebral disease (VCD), 15 with coronary heart disease, 17 with peripheral vascular disease (PVD). Each subject, fasting and without drug treatment at least since 14 hours, after venous blood withdrawal, was given endovenous rapid bolus of 570 lipasemic units of glucuronyl-glucosamine-glycan sulfate (3GS); after 10', 20' and 30' other blood samples were taken; plasma NEFA (colorimetric method) triglycerides (TG), total cholesterol (TC) and HDL-cholesterol (C-HDL) (enzyme method) were assayed; C-HDL/TC ratio was calculated and LDL-cholesterol value (C-LDL) according to the Friedwald-Fredrickson's formula was obtained. In controls NEFA increase after 20' (+ 57%) and triglycerides drop (-49%) were detected; TC significant fall (-13%, P less than 0,05) after 20' was found, preceded by both C-HDL marked increase and C-HDL/TC ratio, and followed (30') by C-LDL slight rise. In the 3 groups of vascular patients a striking NEFA increase (respectively + 50%, + 43%, + 26%) was found; in subjects with PVD/TG blunted drop was observed, whereas in VCD and in CHD TG percentage fall -41 and -44%) did not differ from that one of controls. Evident remarked in control, drop of total cholesterolemia, lacked in the 3 groups of vascular diseases; in patients with VCD and PVD C-HDL and C-HDL/TC ratio increasing profile was like normal, while in CHD both progressive reduction of C-HDL (-19% after 30') and C-HDL/TC ratio with C-LDL increase were appreciated. On the basis of their results the Authors believed that in PVD a striking deficit of total plasma lipoprotein lipase (LPL), already in vitro documented, may occur, whereas LPL resulted normal in VCD and in CHD; on the contrary, in CHD an abnormally cholesterol-apo-VLDL affinity, like metabolic atherogenic derangement, was found; in the 3 groups of vascular diseases slow peripheral cholesterol removal was detectable.

Adult↗

PubMed1995

Superovulation affects glucosamine trisaccharides in the glycocalyx of the rat endometrium at the time of implantation.

The presence of glucosamine trisaccharides in the glycocalyx of surface epithelial cells of the endometrium of hyperstimulated pregnant rats was compared with that of normal pregnant animals by means of lectin-avidin-ferritin histochemistry. The lectin Phytolacca americana was used. A statistically significant reduction in ferritin particles and hence, glucosamine trisaccharides, was found in the glycocalyx of the hyperstimulated animals when compared with that of the controls. This reduction could contribute to the failure of implantation in hyperstimulated animals.

Animals↗

PubMed1996

Active site-directed inactivation of Escherichia coli glucosamine-6-phosphate synthase. Determination of the fructose 6-phosphate binding constant using a carbohydrate-based inactivator.

Glucosamine-6-phosphate synthase (GlmS) catalyzes the formation of glucosamine 6-phosphate from fructose 6-phosphate using glutamine as the ammonia source. Because N-acetylglucosamine is an essential building block of both bacterial cell walls and fungal cell wall chitin, the enzyme is a potential target for antibacterial and antifungal agents. N-Iodoacetylglucosamine 6-phosphate is an active site-directed irreversible inactivator of GlmS from Escherichia coli (kinact/KI = 17 (+/-3) m-1 s-1). Both fructose 6-phosphate and glutamine protect the enzyme from inactivation, indicating that this reagent is directed at both the sugar binding site and the glutamine binding site. Protection studies with fructose 6-phosphate demonstrate that the value of the dissociation constant for fructose 6-phosphate is 3.3 (+/-0.5) x 10(-7) m, approximately 3 orders of magnitude less than the Kia value for this substrate determined from initial velocity experiments (Badet, B., Vermoote, P., and Le Goffic, F. (1988) Biochemistry 27, 2282-2287).

Acetylglucosamine↗

PubMed1977

Inhibition of glucosamine synthesis by salicylates, hydrocortisone and two non-ulcerogenic drugs.

The in vitro inhibition of the glucosamine synthetase activity of rat gastric mucosal homogenates by sodium salicylate and phenylbutazone has been previously reported and has been adduced as a possible mechanism for the ulcerogenic effect of these drugs. This inhibition has been confirmed in human gastric and colonic mucosal homogenates and it is also shown by acetylsalicylic acid and by hydrocortisone hemisuccinate. However, paracetamol and gentamicin, neither of which is known to be ulcerogenic, also inhibited the enzyme to a similar degree to the ulcergenic drugs. This refutes glucosamine synthetase inhibition as the mechanism of the ulcerogenic action of anti-inflammatory drugs.

Acetaminophen↗

PubMed1998

Partial purification and kinetic properties of three different D-glucosamine 6-P:N-acetyltransferase forms from human placenta.

Three distinct forms of D-glucosamine 6-D (Gm 6-P):N-acetyltransferases (EC 2.3.1.4) were partially purified from human placental homogenates by carboxy methyl-Sephadex chromatography. Purification of forms I and II were 13.5-fold, while that of form III was 114-fold. All three forms had a pH optimum value of 9.7 in glycine-NaOH buffer. Enzymes II and III had a K(m) value for Gm 6-P of 3.0 mM, which was less than half of that observed for form I (7.1 mM). The corresponding K(m) values for acetyl CoA were 0.157 (form I), 0.187 (form II) and 0.280 mM (form III), respectively. Activities of all three forms were inhibited at high concentrations of either substrate. These enzymes were inhibited from 82 to 92% by 2.5 mM p-chloromercuribenzoate. The inhibition was largely reversible by inclusion of 2.5 mM dithiothreitol in the incubation mixtures. There was no requirement for divalent cations, as demonstrated by lack of inhibition of enzyme activity by ethylene diamine tetraacetate. The results are discussed in terms of differences among the enzyme properties of human placental, rodent and porcine liver forms.

Acetyl Coenzyme A↗

PubMed1999

Differences in metabolism of 5-fluorouracil and 5-fluorouridine and regulation by glucosamine in human colon cancer multicell tumor spheroids.

Glucosamine (GlcN) modulates fluoropyrimidine metabolism and enhances cytotoxicity of 5-fluorouridine (FUrd), but not of 5-fluorouracil (FUra), in human tumor models. To elucidate the underlying metabolic differences between FUra and FUrd, by the use of 19F and 31P NMR spectroscopy we studied these drugs in multicell tumor spheroids (MTS) formed by human colon carcinoma cells HT-29. This experimental system allowed detailed kinetic measurements of anabolic intracellular phosphates and fluorophosphates over periods of up to 2 days. Time-dependent NMR data were reduced and interpreted by the use of nonlinear compartmental models which yielded numerical values for the empirical rate constants characterizing mass transfer among the compartments. An analysis of these rate constants indicated qualitative and quantitative differences in the metabolism of FUra and FUrd and in the effects of GlcN on these drugs. The enhanced generation of FUDP-hexoses was a predicted effect of GlcN, but inhibited formation of fluorouridine diphosphates and fluorouridine triphosphates in FUra-treated MTS, and the magnitude of stimulation of fluoropyrimidine incorporation into macromolecules in FUrd-treated MTS were not predicted.

Body Fluid Compartments↗

PubMed2001

Preferential incorporation of glucosamine into the galactosamine moieties of chondroitin sulfates in articular cartilage explants.

OBJECTIVE: To determine the metabolic fate of glucosamine (GlcN) in intact articular cartilage tissue. METHODS: Intact articular cartilage explants were cultured for up to 13 days in Dulbecco's modified Eagle's medium supplemented with 1) 1-13C-labeled GlcN, 2) 1-13C-labeled glucose (Glc), or 3) no labeling. Every 3-4 days, samples were removed and frozen in liquid nitrogen for carbon-13 magnetic resonance spectroscopic (MRS) analysis. The metabolic products of the labeled precursors were determined from the MRS data based on resonance positions and comparison with known standards and published values. RESULTS: GlcN was taken up by the chondrocytes and incorporated selectively into the hexosamine, but not the hexuronic acid, components of the glycosaminoglycan chains of articular cartilage proteoglycan. The data also demonstrated that GlcN is the substrate of choice for the galactosamine moieties of the chondroitin sulfates, incorporating at levels 300% higher than with an equivalent amount of labeled Glc. CONCLUSION: The results indicate that GlcN facilitates the production of proteoglycan components that are synthesized through the hexosamine biochemical pathway.

Animals↗

PubMed2002

Effect of oral glucosamine on cartilage and meniscus in normal and chymopapain-injected knees of young rabbits.

OBJECTIVE: To determine if oral glucosamine (GlcN) improves joint biology after acute damage by a protease. METHODS: The effect of 8 weeks of dietary GlcN (20 or 100 mg/kg/day) on knee joint cartilage was evaluated in 2.2-kg male NZW rabbits with and without damage introduced by intraarticular injection of chymopapain (CP). Cartilage was evaluated histologically and scored according to the Mankin scale. Analyses of total hydroxyproline and glycosaminoglycan (GAG) contents and reverse transcription-polymerase chain reaction (RT-PCR) analysis of selected genes were performed. RESULTS: After 8 weeks, there was no effect of GlcN on the GAG content of normal cartilage. Both levels of GlcN treatment significantly increased the sulfated GAG content in the cartilage of the medial femoral condyle in damaged and contralateral knees, but did not change the collagen content. In CP-injected knees, there was still some loss of surface proteoglycan (PG) that was not completely corrected by dietary GlcN. Even after 8 weeks, levels of messenger RNA (mRNA) detected by RT-PCR showed changes indicative of damage and repair, such as elevated type II collagen mRNA, and these levels were not influenced by GlcN treatment. Meniscal GAG content was increased in the contralateral knee of rabbits receiving high-dose GlcN, but was decreased in those receiving no GlcN or low-dose GlcN. Neither diet nor treatment affected the meniscal collagen content. CONCLUSION: These results suggest that oral GlcN treatment might be useful in a situation where GlcN is limiting, such as where there is a rapid replacement of cartilage PG.

Administration, Oral↗

PubMed2004

The bioavailability and pharmacokinetics of glucosamine hydrochloride and chondroitin sulfate after oral and intravenous single dose administration in the horse.

OBJECTIVE: The purpose of this study was to determine if glucosamine (GL) hydrochloride (FCHG49) and low molecular weight (LMW) chondroitin sulfate (CS) (TRH122) are absorbed after oral administration to horses. The bioavailability of LMWCS was evaluated by quantifying the total disaccharides found in the plasma following chondroitinase ABC digestion. METHODS: Two separate studies were conducted. In study 1, ten adult horses received the following four treatments in a randomized crossover fashion: (1) i.v. LMWCS (3 g of 8 kDa), (2) p.o. LMWCS (3 g of 8 kDa), (3) i.v. LMWCS (3 g of 16.9 kDa) and (4) p.o. LMWCS (3 g of 16.9 kDa). Each group received 9 g GL with LMWCS. In a second study, each horse (n=2) was randomly assigned to receive either i.v. administration of GL HCl (9 g) or p.o. administration of GL HCl (125 mg/kg). Blood samples were collected, assayed and pharmacokinetic parameters were determined. RESULTS: GL was absorbed after oral dosing with a mean C(max) of 10.6 (6.9) microg/ml and a mean T(max) of 2.0 (0.7) h. The extent of absorption of LMWCS after dosing with both the 8.0 and 16.9 kDa provides evidence that LMWCS is absorbed orally. C(max) and AUC were higher (p<0.05) for the 16.9 kDa material compared with 8.0 kDa. However, the 16.9 kDa bioavailability was less than 8.0 kDa, but this difference was not significant. CONCLUSIONS: This study provides the first report of the bioavailability of orally administered GL and LMWCS in the horse.

Administration, Oral↗

PubMedDate not supplied

Alkylating agents from sugars: synthesis of chlorambucil derivatives carried by chiral glycosyl glycerols derived from D-glucosamine.

Chlorambucilamide derivatives involving chiral glycosyl glycerols derived from D-glucosamine were synthesized in good yield by coupling the chlorambucil moiety to the amino group of omega-amino-(omega-1)-hydroxyalkyl 2-acylamino-4,6-O-benzylidene-2-deoxy-beta-D-glucopyranosides, and subsequent hydrolysis of the benzylidene group. The starting material was easily available from 2-acetamido-2-deoxy-D-glucose. The bonding of 2,3,4,6-tetra-O-pivaloyl-beta-D-galactopyranosylamine to chlorambucil by formation of an amide function is also described.

Alkylating Agents↗

PubMed1983

A cross-reacting human idiotype (B17) associated with antibodies to N-acetyl-D-glucosamine. Specificity, immunoglobulin class association, and distribution in the population.

This report describes the study of the expression of an idiotype in the human population which is associated with antibodies to N-acetyl-D-glucosamine (GlcNAc) present in most human sera presumably due to streptococcal infections. The idiotype is identified with antisera and monoclonal antibodies prepared against the IgM (kappa) antibody secreted by the Epstein-Barr virus-transformed human B cell line B17. At least 90% of 207 individuals tested had immunoglobulin with B17 idiotypic determinants in their sera, as demonstrated with conventional and one monoclonal anti-idiotypic antibody. Another monoclonal anti-idiotypic antibody reacted with antibodies in only a few of the sera. No correlation was found between the level of expression of different idiotopes in individual human sera, suggesting molecular heterogeneity of the B17-positive antibody population. B17-positive immunoglobulins are to a large extent specific for GlcNAc but represent only a minor population of all GlcNAc-specific antibodies in human sera. B17 determinants are on IgM (kappa) in all human sera and on IgG and IgA in some. In addition, some lambda-bearing Ig was found to react with anti-B17 antisera, suggesting the detection of VH-associated idiotypic determinants in this experimental system.

Acetylglucosamine↗

PubMed1986

Structural requirements for inducing in vitro B lymphocyte activation by chemically synthesized derivatives related to the nonreducing D-glucosamine subunit of lipid A.

Mitogenic and polyclonal B cell activation (PBA) activities of 16 synthetic compounds related to the nonreducing D-glucosamine (GlcN-II) subunit of lipid A were investigated. Among compounds possessing the GlcN backbone, a 4-O-phosphorylated GlcN derivative carrying N-linked 3-tetradecanoyloxytetradecanoyl [C14-O-(C14)] and 3-O-linked tetradecanoyl (C14) groups, GLA-27, expressed the highest degree of both activities. Omission of the 3-O-linked C14 group from GLA-27 and transfer of the C14 group to the C-6 position induced critical changes in expression of activities. Both 4-O-phosphorylated compounds carrying an N-linked C14 or 3-hydroxytetradecanoyl (C14OH) group instead of the C14-O-(C14) group in GLA-27 showed no detectable activity. Substituting a 3-O-linked C14 group in GLA-27 for the C14-O-(C14) group also markedly decreased mitogenic and PBA activities. Change of phosphorylation site from the C-4 to the C-6 position and bisphosphorylation at the C-4 and C-6 positions induced somewhat weak depression. Much weaker activities were observed in a compound carrying N-linked 3-dodecanoyloxydodecanoyl [C12-O-(C12)] and 3-O-dodecanoyl (C12) as fatty acid substituents. No detectable activity was seen in a compound carrying N-linked 3-hexadecanoyloxyhexadecanoyl [C16-O-(C16)] and 3-O-hexadecanoyl (C16), indicating that the most suitable carbon chain length for expressing the activities is C14. Regarding structural change of the GlcN backbone, a 1-deoxy derivative of GLA-27 exhibited stronger activity than did GLA-27 itself. Mitogenic and PBA activity of GLA-27 were stronger than those of lipid X, which corresponds to the reducing D-GlcN (GlcN-I) subunit of Escherichia coli lipid A and is a 1-O-phosphorylated GlcN derivative carrying N- and 3-O-linked C14OH groups. These results indicate that N-linked acyloxyacyl and 3-O-linked acyl groups and phosphorylation are critical for expressing both mitogenic and PBA activities.

Animals↗

PubMed1987

Platelet-derived growth factor stimulation of [3H]-glucosamine incorporation in density-arrested BALB/c-3T3 cells.

G0/G1 traverse in density-arrested BALB/c-3T3 cells is controlled by multiple serum-derived growth factors. Platelet-derived growth factor (PDGF) initiates a proliferative response, whereas factors present in plasma facilitate progression through G0/G1. In the absence of competence formation, progression factors are unable to stimulate cell cycle traverse. We have identified the stimulation of a biochemical process specific to competence formation in BALB/c-3T3 cells. PDGF treated BALB/c-3T3 cells incorporated 5-10-fold more [3H]-glucosamine (GlcN) into acid-insoluble material as compared to platelet-poor plasma (PPP) treated cultures. Increased GlcN incorporation occurred in density-arrested BALB/c-3T3 cells in response to treatment with other competence factors, fibroblast growth factor, and Ca3 (PO4)2 and was not due to cell-cycle traverse. Stimulation of [3H]-GlcN incorporation by PDGF was time dependent, and increased incorporation of [3H]-GlcN into protein required de novo protein synthesis. Several mechanisms through which PDGF could increase GlcN incorporation into cellular material were examined. Results of these studies suggest an increase in the cellular capacity to glycosylate proteins is a response to or a part of competence formation.

Animals↗

PubMed2002

Complete amino acid sequence and characterization of the reaction mechanism of a glucosamine-induced novel alcohol dehydrogenase from Agrobacterium radiobacter (tumefaciens).

A glucosamine-induced novel alcohol dehydrogenase has been isolated from Agrobacterium radiobacter (tumefaciens) and its fundamental properties have been characterized. The enzyme catalyzes NAD-dependent dehydrogenation of aliphatic alcohols and amino alcohols. In this work, the complete amino acid sequence of the alcohol dehydrogenase was determined by PCR method using genomic DNA of A. radiobacter as template. The enzyme comprises 336 amino acids and has a molecular mass of 36 kDa. The primary structure of the enzyme demonstrates a high homology to structures of alcohol dehydrogenases from Shinorhizobium meliloti (83% identity, 90% positive) and Pseudomonas aeruginosa (65% identity, 76% positive). The two Zn(2+) ion binding sites, both the active site and another site that contributed to stabilization of the enzyme, are conserved in those enzymes. Sequences analysis of the NAD-dependent dehydrogenase family using a hypothetical phylogenetic tree indicates that these three enzymes form a new group distinct from other members of the Zn-containing long-chain alcohol dehydrogenase family. The physicochemical properties of alcohol dehydrogenase from A. radiobacter were characterized as follows. (1) Stereospecificity of the hydride transfer from ethanol to NADH was categorized as pro-R type by NMR spectra of NADH formed in the enzymatic reaction using ethanol-D(6) was used as substrate. (2) Optimal pH for all alcohols with no amino group examined was pH 8.5 (of the C(2)-C(6) alcohols, n-amyl alcohol demonstrated the highest activity). Conversely, glucosaminitol was optimally dehydrogenated at pH 10.0. (3) The rate-determining step of the dehydrogenase for ethanol is deprotonation of the enzyme-NAD-Zn-OHCH(2)CH(3) complex to enzyme-NAD-Zn-O(-)CH(2)CH(3) complex and that for glucosaminitol is H(2)O addition to enzyme-Zn-NADH complex.

Alcohol Dehydrogenase↗

PubMed1997

Quantitative determination of amino acid levels in neutral and glucosamine-containing carbohydrate polymers.

Low-level (subanomole) determination of amino acids in samples of naturally derived polymeric carbohydrates has been demonstrated using vapor-phase acid hydrolysis and subsequent precolumn derivatization with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate. Application has been demonstrated for neutral polysaccharide polymers such as laminarin (beta-1,3; branched), curdland (beta-1,3; unbranched), pullulan (alpha-1, 6-maltotriose), glycogen (alpha-1,4-glucan), and inulin (polyfructose). Successful determination (acceptable recovery and lack of interferences) was possible in samples which also contained up to roughly 50 micrograms amino sugars (e.g., chitosan or glucans with copurified glucosamine oligomers), although optimum utility is for samples containing up to ca. 10 micrograms total amines. The limit of quantification was roughly 20 ng protein/ mg sample, based on analysis of reagent blanks, although the limit of detection was much lower (ca. 0.1 ng protein/mg sample). Incorporation of a relatively rapid hydrolysis (150 degrees C for 1.5 h) gave similar results to use of 110 degrees C for 24 h and allowed for relatively rapid processing. The method has shown good sensitivity, linearity, ruggedness, and ease. Recovery has been optimized, although yield varied somewhat depending on polymer composition.

Amino Acids↗

PubMed2000

Glucosamine and chondroitin sulfates in the treatment of osteoarthritis: a survey.

For more than 30 years, non-steroidal anti-inflammatory drugs (NSAIDs) have been used as standards in the treatment of osteoarthritis (OA). Serious and often life-threatening adverse effects due to these agents are common. Clinical findings have revealed that glucosamine sulfate and chondroitin sulfate are effective and safer alternatives to alleviate symptoms of OA. Experimental evidence indicates that these compounds and their low molecular weight derivatives have a particular tropism for cartilage where they serve as substrates in the biosynthesis of component building blocks. This paper is a literature review of the chemistry, mechanism of action, pharmacokinetics, clinical efficacy and safety of these two nutraceuticals.

Chondroitin↗

PubMed1985

Effect of 2-deoxyglucose, alpha-methylglucoside, and glucosamine on aflatoxin production by Aspergillus parasiticus.

The effects of 2-deoxyglucose (2-DOG), alpha-methylglucoside (alpha-MG), and glucosamine (GA) on aflatoxin production by Aspergillus parasiticus were studied using conidia-initiated and replacement cultures. In conidia-initiated, 2-DOG, alpha-MG, and GA supported varying amounts of growth when employed as sole carbon sources. In both conidia-initiated and replacement cultures, 2-DOG, but not alpha-MG nor GA, as sole carbon sources support toxin formation. None of the compounds inhibited aflatoxin production when used in combination with glucose. It appears that neither 2-DOG, alpha-MG, nor GA can be considered nonmetabolizable analogs of glucose in A. parasiticus.

Aflatoxins↗