Urinary Glycosaminoglycan Concentration Research Articles

The SPRT control charts for the Maxwell distribution

AbstractMaxwell distribution has several applications in modeling physical and chemical processes, as well as in reliability and lifetime data analysis. In this paper, we propose the one‐ and two‐sided SPRT control charts for monitoring the scale parameter of a Maxwell distributed process. Using a Markov chain approach, we obtain the measures of statistical performance for the one‐sided charts. Reasonably accurate relationships between the performance measures of a two‐sided SPRT chart and that of its corresponding one‐sided charts are derived through Monte‐Carlo simulations. Approaches for designing the one‐ and two‐sided SPRT charts having the specified in‐control and the optimal out‐of‐control performances are provided. The results of the numerical study reveal that the proposed charts significantly outperform the Shewhart and cumulative sum (CUSUM) charts for detecting a shift of any size in the scale parameter. The mechanisms of the one‐ and two‐sided SPRT charts are illustrated via two real‐data examples: the first in the monitoring of the urinary glycosaminoglycan concentration and the second in the monitoring of the bearing life.

Urinary glycosaminoglycan concentration as a biomarker for effectiveness of enzyme replacement and gene therapy in large animal models of mucopolysaccharidoses

Urinary glycosaminoglycan concentration as a biomarker for effectiveness of enzyme replacement and gene therapy in large animal models of mucopolysaccharidoses

Urinary Glycosaminoglycan Estimation as a Routine Clinical Service.

Mucopolysaccharidoses, a group of inherited disorders are associated with defects in glycosaminoglycan metabolism. Thus, assessment of urinary glycosaminoglycan is used as a screening test for mucopolysaccharidoses. The detection methods range from qualitative spot tests to quantification using metachromatic dyes. In our laboratory we optimized a spectrophotometric quantitative method using a metachromatic dye, dimethylmethylene blue. Heparan sulfate was used for quantification. The glycosaminoglycan-dye complex showed a marked shift in color with increase in concentration. The color complex was quantified at 520nm. The method was linear from 10-89mg/L. An age matched normal range was obtained in 177 healthy individuals, grouped in 8 different age groups from neonates to adults. Urinary glycosaminoglycan concentration varied distinctly amongst the study population wherein the lowest range in healthy neonates was more than 3 times the upper limit of healthy adults. Urine samples from 10 patients with mucopolysaccharidoses were also included in the study for clinical validation. The method qualified both analytical and clinical validation and was found to be simple, robust and ideal to be offered as a screening test for mucopplysaccharidoses in a routine clinical chemistry laboratory.

Influence of proteolytic–antiproteolytic enzymes and prooxidative–antioxidative factors on proteoglycan alterations in children with juvenile idiopathic arthritis

ObjectivesThe influence of proteolytic–antiproteolytic enzymes and prooxidative–anti-oxidative factors on proteoglycan alterations in children with juvenile idiopathic arthritis (JIA) was evaluated in this study. Design, methods, resultsPlasma and urinary glycosaminoglycans (GAGs), as well as plasma levels of matrix metalloproteinases (MMPs) (MMP-3, MMP-10), tissue inhibitors of metalloproteinases (TIMPs) (TIMP-1, TIMP-2), total oxidative status (TOS) and total antioxidative status (TAS), were quantified in samples obtained from 30 healthy subjects and 30 JIA patients before and after treatment. Significantly decreased plasma and urinary concentration of GAGs in JIA patients before treatment was observed. Therapy resulted in an increase in the concentration of the above listed parameters. However, the plasma GAG level still remained significantly lower compared to that in controls. Increased levels of MMP-3 and TIMP-1 in both JIA patient groups were recorded. The plasma MMP-10 and TIMP-2 concentrations in untreated patients were significantly decreased. Anti-inflammatory treatment led to normalization of these parameter concentrations. Significant increase of TOS but decrease of TAS was found in the blood of untreated patients. The treatment resulted only in the normalization of TOS concentration. We have revealed a significant correlation between plasma GAGs and: MMP-3 (r=0.54), TOS (r=0.64) and urinary GAGs (r=0.55), respectively. ConclusionsProteoglycan/glycosaminoglycan alterations in JIA patients, which are stimulated by MMP-3 and reactive oxygen species (ROS), indicate rather systemic disturbance of extracellular matrix metabolism, and not merely local changes which occur in articular structures. Given the destructive potential of ROS and MMPs and their hyperexpression in JIA, inhibition of these compounds should bring a substantial clinical benefit.

Long-term efficacy of hematopoietic stem cell transplantation on brain involvement in patients with mucopolysaccharidosis type II: A nationwide survey in Japan

Hematopoietic stem cell transplantation (HSCT) has not been indicated for patients with mucopolysaccharidosis II (MPS II, Hunter syndrome), while it is indicated for mucopolysaccharidosis I (MPS I) patients <2years of age and an intelligence quotient (IQ) of ≥70. Even after the approval of enzyme replacement therapy for both of MPS I and II, HSCT is still indicated for patients with MPS I severe form (Hurler syndrome). To evaluate the efficacy and benefit of HSCT in MPS II patients, we carried out a nationwide retrospective study in Japan. Activities of daily living (ADL), IQ, brain magnetic resonance image (MRI) lesions, cardiac valvular regurgitation, and urinary glycosaminoglycan (GAG) were analyzed at baseline and at the most recent visit. We also performed a questionnaire analysis about ADL for an HSCT-treated cohort and an untreated cohort (natural history). Records of 21 patients were collected from eight hospitals. The follow-up period in the retrospective study was 9.6±3.5years. ADL was maintained around baseline levels. Cribriform changes and ventricular dilatation on brain MRI were improved in 9/17 and 4/17 patients, respectively. Stabilization of brain atrophy was shown in 11/17 patients. Cardiac valvular regurgitation was diminished in 20/63 valves. Urinary GAG concentration was remarkably lower in HSCT-treated patients than age-matched untreated patients. In the questionnaire analysis, speech deterioration was observed in 12/19 patients in the untreated cohort and 1/7 patient in HSCT-treated cohort. HSCT showed effectiveness towards brain or heart involvement, when performed before signs of brain atrophy or valvular regurgitation appear. We consider HSCT is worthwhile in early stages of the disease for patients with MPS II.

Pharmacokinetic profile of recombinant human N‐acetylgalactosamine 4‐sulphatase enzyme replacement therapy in patients with mucopolysaccharidosis VI (Maroteaux–Lamy syndrome): a phase I/II study

Mucopolysaccharidosis VI (Maroteaux-Lamy syndrome) is a lysosomal storage disease caused by a deficiency of the enzyme-N-acetylgalactosamine 4-sulphatase (ASB). Enzyme replacement therapy with recombinant human ASB (rhASB) has been studied in a randomized, double-blind, two-dose (0.2 and 1.0 mg/kg/week) phase I/II study (n = 7) followed by an open-label single dose (1.0 mg/kg/week) extension study. We report the pharmacokinetic profile of rhASB and the impact of antibody development. Pharmacokinetic analysis was performed at weeks 1, 2, 12, 24, 83, 84 and 96. Infusions were administered over 4 hours using a ramp-up protocol. Plasma ASB and rhASB antibody concentrations and urine glycosaminoglycan (GAG) concentrations were determined. The area under the plasma concentration-time curve (AUC(0-t)) for the high-dose group increased from week 1 to week 2, but remained unchanged at weeks 12 and 24. A large difference in mean AUC(0-t) was observed between the low- and high-dose groups. Pharmacokinetic results at weeks 83, 84 and 96 were similar to those at week 24. Six patients developed antibodies to rhASB. One patient developed high antibody levels in combination with a high ASB concentration, while a second patient also developed high antibody levels with undetectable ASB concentrations. Antibodies from the second patient blocked detection of ASB. By week 72, antibody levels had decreased in all patients. The high-dose rhASB produced a more rapid and greater percentage reduction in urinary GAG concentrations than the lower dose (70% versus 55% at 24 weeks). Antibody levels did not appear to influence urinary GAG concentrations. Pharmacokinetic parameters appear to be independent of the duration of treatment and are not linear between the 0.2 and 1.0 mg/kg/week doses. Antibodies to rhASB develop in most patients, but their concentration decreases over time. Antibody formation may influence pharmacokinetic parameters during the early phases of treatment, although it appears to have limited impact on biochemical efficacy.

Changes in cat urinary glycosaminoglycans with age and in feline urologic syndrome.

The aim of the present study was to characterize the urinary excretion of glycosaminoglycans in kittens and adult healthy cats, as well as in cats with a low urinary tract disease, the feline urologic syndrome (FUS). The main urinary glycosaminoglycan in cats was found to be chondroitin sulfate, with smaller amounts of dermatan sulfate and heparan sulfate. There was no difference in the urinary glycosaminoglycan concentration with sex, but a marked decrease occurred with age, due to chondroitin sulfate. Trace amounts of keratan sulfate were also detected in the urine of kittens, but not of healthy adult cats. Dermatan sulfate and heparan sulfate were the only glycosaminoglycans found in the urinary tract and kidney, and chondroitin sulfate was the only glycosaminoglycan found in the plasma. These data suggest that the main urinary glycosaminoglycan chondroitin sulfate is of systemic origin and filtered in the kidney, while the minor components dermatan sulfate and heparan sulfate may come from the urinary tract. The urinary glycosaminoglycan concentration was greatly decreased in animals with FUS, as compared to normal adults. We hypothesize that these low glycosaminoglycan levels reflect a damage to the bladder surface, resulting in absorption and/or degradation of the endogenous urinary glycosaminoglycans.

Replacement therapy in Mucopolysaccharidosis type VI: advantages of early onset of therapy

This study evaluates the immunological response following weekly 2 h infusions of recombinant human N-acetylgalactosamine 4-sulfatase (rh4S) in Mucopolysaccharidosis VI (MPS VI) cats. The results of three trials (Trial “A”: 9 month duration with onset at 3–5 months of age, n=5; and Trials “B” and “C”: 6 month duration starting at birth, n=9) were compared. No detrimental effects were noted throughout Trials B and C. Temporary hypersensitivity reactions (e.g., vomiting, diarrhoea) occurred in four cats in Trial A and were alleviated by increasing the dose of antihistamine premedication and the duration of infusion. All cats in Trial A developed antibodies to rh4S (range of final titres: 1041–134,931). All cats treated from birth showed negligible titres (range: <50–598). In vitro inhibition of rh4S activity (up to 47%) was demonstrated with plasma from four cats with elevated titres. Significant reduction of urinary glycosaminoglycan concentration in all cats indicated the ability of rh4S to metabolize stored substrates regardless of the presence of circulating antibodies. Similarly, lysosomal storage in reticuloendothelial cells and fibroblasts of kidney interstistium, dura and skin was reduced in all cats irrespective of their antibody titre although cats with elevated titre had less beneficial effect on cardiovascular tissues (aorta smooth muscle cells, heart valve fibroblasts). Overall improvement in the disease condition (at physical, neurological, and skeletal levels) was most pronounced for cats treated from birth compared with cats treated at a later age.

The effect of Phyllanthus niruri on urinary inhibitors of calcium oxalate crystallization and other factors associated with renal stone formation.

To evaluate the effect of an aqueous extract of Phyllanthus niruri (Pn), a plant used in folk medicine to treat lithiasis, on the urinary excretion of endogenous inhibitors of lithogenesis, citrate, magnesium and glycosaminoglycans (GAGs). The effect of chronic (42 days) administration of Pn (1.25 mg/mL/day, orally) was evaluated in a rat model of urolithiasis induced by the introduction of a calcium oxalate (CaOx) seed into the bladder of adult male Wistar rats. The animals were divided into four groups: a sham control (16 rats); a control+Pn (six); CaOx+water instead of Pn (14); and CaOx+Pn (22). Plasma and urine were collected after 42 days of treatment for biochemical analysis and the determination of urinary excretion of citrate, magnesium and GAGs. The animals were then killed and the calculi analysed. The creatinine clearance or urinary and plasma concentrations of Na+, K+, Ca2+, oxalate, phosphate and uric acid were unaffected by Pn or the induction of lithiasis. Treatment with Pn strongly inhibited the growth of the matrix calculus and reduced the number of stone satellites compared with the group receiving water. The calculi were eliminated or dissolved in some treated animals (three of 22). The urinary excretion of citrate and magnesium was unaffected by Pn treatment. However, the mean (sd) urinary concentration of GAGs was significantly lower in rats treated with CaOx+Pn, at 5.64 (0.86) mg/g creatinine, than when treated with CaOx + water, at 11.78 (2.21) mg/g creatinine. In contrast, the content of GAGs in the calculi was higher in the CaOx + Pn rats, at 48.0 (10.4) g/g calculus, than in the CaOx + water group, at 16.6 (9.6) g/g calculus. These results show that Pn has an inhibitory effect on crystal growth, which is independent of changes in the urinary excretion of citrate and Mg, but might be related to the higher incorporation of GAGs into the calculi.

Urinary heparan sulfate proteoglycan excretion in black African women with pre-eclampsia.

The heparan sulfate proteoglycan of the glomerular basement membrane is considered to be mainly responsible for the charge selectivity of the glomerular basement membrane. Decreased heparan sulfate proteoglycan results in a decreased anionic charge of the glomerular basement membrane with increased heparan sulfate proteoglycan in the urine, and is believed to be responsible for the proteinuria in pre-eclampsia. To determine the urinary heparan and chondroitin sulfate proteoglycan levels in women with pre-eclampsia. Eighty-four patients were studied: 28 were normotensive pregnant, 28 were nonproteinuric hypertensive, and 28 were pre-eclamptic. Urine samples were obtained and urinary glycosaminoglycan concentrations were determined using the dimethyl-methylene blue assay. Plotting absorbance against the concentrations of heparan and chondroitin sulfate proteoglycans drew a standard curve. The concentration of heparan and chondroitin sulfate proteoglycans was read-off from the linear portion of the standard curve. The standard solutions contained 25, 50, 100 and 200 mg/l heparan or chondroitin sulfate. The Mann-Whitney U-test was used to detect differences between the three groups, and the Pearson's correlation coefficient was calculated for clinical data correlation of the pre-eclamptic group. Urinary excretion of heparan sulfate proteoglycan (123.1 +/- 22.1 mg/l) was significantly increased in the pre-eclamptic group compared with the normotensive pregnant group (60.5 +/- 5.1 mg/l; p < 0.0001) and the hypertensive nonproteinuric group (63. 2 +/- 3.7 mg/l; p < 0.0001). Urinary chondroitin sulfate proteoglycan excretion followed a similar pattern, being significantly increased in the pre-eclamptic group (88.86 +/- 9.79 mg/l) compared with the normotensive pregnant group (49.1 +/- 8.49 mg/l; p < 0.0001) and the hypertensive nonproteinuric group (43. 9 +/- 5.7 mg/l; p < 0.0001). A significant Pearson's correlation between 24-h urine output vs. 24-h protein excretion (r = 0.51; p < 0.001), and between loss of HSPG versus 24-h urinary protein excretion (r = 0.72; p < 0.0001) was obtained in the pre-eclamptic group. This study demonstrates a reduction of glomerular charge in pre-eclampsia. The strong correlation between the severity of proteinuria and the loss of charge supports the hypothesis that the loss of glomerular charge induces structural changes of the filtration barrier, and may be the mechanism responsible for the proteinuria in pre-eclampsia. Furthermore, the elevated levels of urinary proteoglycan (heparan and chondroitin sulfate proteoglycans) in this disorder show a loss into the urine rather than a neutralization of these macromolecules.

Clinical association with urinary glycosaminoglycans and urolithiasis

Objectives. To determine the clinical association between urinary glycosaminoglycan (GAG) concentration and kidney stone disease. Methods. Thirty-five patients (14 women and 21 men) with a history of stone disease and 37 controls (13 women and 24 men) were evaluated for urinary GAG concentration. By using a new dye-binding assay, the total GAG concentration in the urine was measured and corrected to urinary creatinine levels (micrograms of GAG per milligram creatinine). Results. The mean urinary GAG concentration in those with stones was significantly lower (31.5 ± 2.6 μg GAG/mg creatinine) than in the controls (43.8 ± 3.8 μg GAG/mg creatinine, P = 0.01). Male patients with stones also had a significantly lower mean GAG concentration (26.1 ± 1.8) than did the female patients (39.6 ± 5.3, P = 0.009). The mean GAG concentration between ureteral (n = 13) versus renal (n = 22), single (n = 19) versus multiple (n = 16), family history (n = 11) versus no family history (n = 24), large (n = 13) versus small (n = 20), and the presence (n = 22) versus absence (n = 13) of residual stones did not show any significant differences. However, patients with recurrent stone formation (n = 21) had significantly lower mean GAG levels (26.4 ± 1.6) compared with those with single stone formation (n = 14; 39.2 ± 5.5, P = 0.01). Conclusions. Lower urinary GAG levels are more common in patients with stone formation. This may play a more determinant role in male patients and those with recurrent stone formation.

Urinary heparan sulfate proteoglycan excretion in black African women with pre-eclampsia

Background. The heparan sulfate proteoglycan of the glomerular basement membrane is considered to be mainly responsible for the charge selectivity of the glomerular basement membrane. Decreased heparan sulfate proteoglycan results in a decreased anionic charge of the glomerular basement membrane with increased heparan sulfate proteoglycan in the urine, and is believed to be responsible for the proteinuria in pre-eclampsia. Aim. To determine the urinary heparan and chondroitin sulfate proteoglycan levels in women with pre-eclampsia. Materials and methods. Eighty-four patients were studied: 28 were normotensive pregnant, 28 were nonproteinuric hypertensive, and 28 were pre-eclamptic. Urine samples were obtained and urinary glycosaminoglycan concentrations were determined using the dimethyl-methylene blue assay. Plotting absorbance against the concentrations of heparan and chondroitin sulfate proteoglycans drew a standard curve. The concentration of heparan and chondroitin sulfate proteoglycans was read-off from the linear portion of the standard curve. The standard solutions contained 25, 50, 100 and 200 mg/l heparan or chondroitin sulfate. The Mann–Whitney U-test was used to detect differences between the three groups, and the Pearson's correlation coefficient was calculated for clinical data correlation of the pre-eclamptic group. Results. Urinary excretion of heparan sulfate proteoglycan (123.1 ± 22.1 mg/l) was significantly increased in the pre-eclamptic group compared with the normotensive pregnant group (60.5 ± 5.1 mg/l; p < 0.0001) and the hypertensive nonproteinuric group (63. 2 ± 3.7 mg/l; p < 0.0001). Urinary chondroitin sulfate proteoglycan excretion followed a similar pattern, being significantly increased in the pre-eclamptic group (88.86 ± 9.79 mg/l) compared with the normotensive pregnant group (49.1 ± 8.49 mg/l; p < 0.0001) and the hypertensive nonproteinuric group (43. 9 ± 5.7 mg/l; p < 0.0001). A significant Pearson's correlation between 24-h urine output vs. 24-h protein excretion (r = 0.51; p < 0.001), and between loss of HSPG versus 24-h urinary protein excretion (r = 0.72; p < 0.0001) was obtained in the pre-eclamptic group. Conclusion. This study demonstrates a reduction of glomerular charge in pre-eclampsia. The strong correlation between the severity of proteinuria and the loss of charge supports the hypothesis that the loss of glomerular charge induces structural changes of the filtration barrier, and may be the mechanism responsible for the proteinuria in pre-eclampsia. Furthermore, the elevated levels of urinary proteoglycan (heparan and chondroitin sulfate proteoglycans) in this disorder show a loss into the urine rather than a neutralization of these macromolecules.

Glycosaminoglycans in thyroid eye disease.

Orbital accumulation of hydrophilic, interstitial glycosaminoglycans (GAG) and subsequent expansion of retrobulbar tissue lead to the clinical manifestation of exophthalmos in patients with thyroid eye disease (TED). In order to analyze whether the alteration of distribution pattern and biochemical composition of GAG and proteoglycans play a role in the development of the disease, a highly specific high-pressure liquid chromatography (HPLC) method was developed. The concentration of total GAG, chondroitin sulfate A (CA), dermatan sulfate (DS), and hyaluronic acid (HA) was determined in patients and controls, revealing marked differences in urinary concentration of total GAG and HA, as well as an elevation of CA in patients versus controls. Method sensitivity was 0.86 for patients with active disease, and 0.87 for patients with untreated ophthalmopathy, whereas specificity was 1.0 for patients with inactive disease. Patients with increased GAG concentration responded well to steroids and/or orbital irradiation. Furthermore, distribution pattern of orbital extracellular matrix GAG exhibited a significant increase in the tissue fractions of CA and HA in patients with TED in comparison to controls. In conclusion, GAG polysaccharides not only play a major role in the pathogenesis of TED but have been successfully introduced as an activity marker of the disease.

Urine glycosaminoglycan concentrations in mucopolysaccharidosis VI-affected cats following bone marrow transplantation or leukocyte infusion

Urinary glycosaminoglycan (GAG) concentrations were determined in nineteen normal cats (eleven kittens and eight adult cats), eighteen mucopolysaccharidosis VI (MPS VI)-affected untreated cats (ten kittens and eight adult cats), thirteen MPS VI-affected cats following bone marrow transplantation (BMT), and two MPS VI-affected cats following intravenous infusion of leukocytes from normal cats. Mucopolysaccharidosis VI-affected cats treated with BMT had a precipitous decrease in urinary GAG by day 7 post-BMT, then a transient increase just prior to engraftment, followed by a sustained decrease to within, or near, the range of urinary GAG concentration established for normal cats. The pre-engraftment changes in urinary GAG excretion were reproduced by leukocyte infusion. After infusion of comparable numbers of normal peripheral blood leukocytes, a significant decrease in urinary GAG concentrations, specifically dermatan sulfate (DS), was seen with a nadir at day 5 post-infusion, followed by a return by day 9 to pre-infusion values. Post-engraftment, a continued low urinary GAG concentration with a specific decrease in DS can be utilized to document successful autologous engraftment in MPS VI-affected cats

Urinary Glycosaminoglycan Concentrations in Postmenopausal Osteoporosis

The organic bone matrix contains glycosaminoglycans (GAGs). Structural changes in bones with inflammatory and degenerative processes generally lead to the break-down of macromolecules from connective tissue and increase their urinary excretion. In the present study, the levels of urinary GAGs were investigated in 28 healthy controls consisting of 18 premenopausal and 10 postmenopausal women and 25 patients with postmenopausal and 10 postmenopausal women and in 25 patients with postmenopausal osteoporosis. Urinary GAGs were measured in 24 hour collected urine samples by the carbazole method and corrected for the excretion level of creatinine. There was a significant increase in GAGs excretion in patients with postmenopausal osteoporosis compared with healthy premenopausal (p

Glycosaminoglycans in urolithiasis.

To determine if there are differences in urinary glycosaminoglycan (GAG) concentrations, 43 stone-forming patients and 37 healthy control subjects of both sexes were studied. Urinary concentrations of calcium, magnesium, creatinine, uric acid and GAGs were determined. GAGs were measured by the Di Ferrante precipitation procedure followed by the Bitter and Muir reaction. Urinary GAG concentration and daily output were significantly lower in stone-forming patients. The present study clearly demonstrates the decreased urinary GAG concentration and excretion in stone-forming patients and suggests an interaction between GAGs and urate that could modify the inhibitory potency of GAGs.

EFFECT OF ALCOHOL ON URINARY GLYCOSAMINOGLYCAN AND PROTEIN EXCRETION IN NORMAL AND DIABETIC MICE

The effect of alcohol on urinary glycosaminoglycan (GAG) and protein excretion was studied in one-month-old normal control C57BL/6J (CBL) and genetically diabetic (db/db) mice. Ethyl alcohol (4 g/kg) was given once a day by gavage for 58-64 days. Increased amounts of urinary total GAGs and protein were found in diabetic mice. Alcohol treatment increased urinary excretion of total GAGs, heparan sulfate and protein only in nondiabetic CBL but not in diabetic mice. Also, alcohol increased creatinine clearance only in CBL mice. The reason for the lack of effect of alcohol in diabetic mice is unknown. A significant positive linear relationship was found between urinary total GAG and protein concentrations. Possible significance of this relationship in diabetes is discussed.