The recovery and characterization of acid glycosaminoglycans in normal human urine. Influence of a circadian rhythm

Our plain-English summary of The recovery and characterization of acid glycosaminoglycans in normal human urine. Influence of a circadian rhythm, by J.E. Scott, D.J. Newton (Connective Tissue Research, 1975).

The study

• Authors: J.E. Scott, D.J. Newton
• Journal: Connective Tissue Research
• Published: 1975;3(2):157-64
• Cited by: 23 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

A method is described for the recovery of acid GAG (AGAG) as solid Ba salts from relatively small volumes (100+/-50 ml) of normal adult human urine. It is pointed out that (a) the amount recovered, (b) the molecular characteristics (i.e. molecular weight and charge density), (c) the ionic strength at which the AGAG are recovered and (d) the "critical electrolyte concentrations" of the AGAG-precipitating reagent (or anion exchanger) are inseparably linked, and that different fractions are obtained by variations in any parameter. Our product is defined as that fraction of heterodisperse material precipitated at room temperature by cetyl trimethylammonium bromide from urine diluted with 3 volumes of 0.05 M sodium acetate buffer pH 5.7, in the presence of asbestos powder. It is less degraded than other AGAG remaining in the urine supernatant. The product contained three electrophoretically separa0le components, characterized by susceptibility to pronase digestion, infrared and ultraviolet spectroscopy, hexosamine identification, tests for uronic and sialic acids, and the "critical electrolyte concentrations" of their Alcian blue complexes, as "chondroitin sulphate", "heparan sulphate" and acid glycoprotein. The method is simple, rapid and suita0le for use on multiple samples. The product is directly usable in electrophoretic analyses, etc. Using this method AGAG was recovered from the urine of nine males and five females, aged 25-43, collected during a 24-hr cycle, in six 4-hr aliquots. The ratios of "chondroitin sulphate" to "heparan sulphate" quantitated from the electrophoretic strip, showed a marked peak in every subject at 18-22 hrs.

In plain English

This was a laboratory methods paper, not a study of asbestos exposure or disease. The authors developed a way to recover acid glycosaminoglycans (breakdown products of connective tissue) from normal human urine. They used commercial asbestos powder as a laboratory adsorbent during precipitation with the chemical CTAB. The article does not name the asbestos fiber type. In their comparison, asbestos recovered more material than another adsorbent, Celite, especially material in the "heparan sulphate" band. In one experiment, precipitation for 2 hours gave over 95% of the yield obtained in 24 hours. The recovered material separated into three components, identified as mainly "chondroitin sulphate", "heparan sulphate" and acid glycoprotein. The method was applied to urine from 14 healthy adults (nine male, five female, aged 25-43), each collected as six 4-hour samples over 24 hours. The ratio of chondroitin sulphate to heparan sulphate ranged from 2.7 to 11.8 and peaked at 18-22 hours in every subject. The authors concluded that, to the extent their isolated material is representative, the results support differential control of the metabolism of different connective tissues during activity and rest.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: Laboratory methods development study, with an application to timed urine samples from healthy volunteers
• Who was studied: Urine from 14 healthy adults (nine male, five female) aged 25-43 who were not on medication, each collected as six 4-hour samples over a 24-hour cycle; the article does not state the location or dates of collection
• Exposure: No human asbestos exposure was studied. Commercial asbestos powder (fiber type not named) was used as a laboratory adsorbent to collect the precipitated material from urine.
• Main results:
  • In the authors' comparison, asbestos powder recovered more total urinary acid glycosaminoglycan than Celite, particularly material in the "heparan sulphate" band. At 2 hrs, asbestos gave 1.30 and 0.235 Alcian blue units for the chondroitin sulphate and heparan sulphate bands; Celite gave 1.08 and 0.15.
  • In one experiment, precipitation for 2 hours gave over 95% of the amount obtained in 24 hours.
  • In one experiment, precipitating at room temperature rather than at 4 degrees C increased recovered "heparan sulphate" by 91%.
  • The recovered material contained three components: band 1 mainly "chondroitin sulphate", band 2 mainly "heparan sulphate" and band 3 acid glycoprotein.
  • Recovery was 0.53-1.3 mg uronic acid per gm creatinine on 14 samples. On 12 urine samples it was about 30% of the recovery by Whiteman's Alcian blue method.
  • Across the 14 subjects, the chondroitin sulphate to heparan sulphate ratio varied from 2.7 to 11.8, with a well-marked maximum in every subject at 18-22 hrs.
• The authors' conclusion: The authors concluded that, to the extent their isolated material represents degraded connective tissue material, the results support the idea that metabolic activity of different connective tissues is differentially controlled during normal activity and rest.
• Limitations the authors state:
  • The authors noted that the nature of the water-insoluble part of the recovered material had not been determined.
  • The authors cautioned that urinary material cannot be identified simply by comparing its electrophoresis with tissue extracts, because it appears degraded.

Topics

Medical terms in this study, explained in our Lexicon: Glycoprotein.

Related studies

• Effect of insulin and epidermal growth factors on the synthesis of glycosaminoglycans/proteoglycans in cultured human malignant mesothelioma cells of different phenotypic morphology — G.N. Tzanakakis, N.K. Karamanos, et al. (1996)
• Glycosaminoglycans from two human malignant mesothelioma cell lines: determination, distribution, and effect of platelet-derived growth factor on their synthesis — G.N. Tzanakakis, N.K. Karamanos, et al. (1995)
• Acetic acid induces cell death: an in vitro study using normal rat gastric mucosal cell line and rat and human gastric cancer and mesothelioma cell lines — S. Okabe, T. Okamoto, et al. (2014)
• Hemolysis by chrysotile asbestos fibers. I. Influence of the sialic acid content in human, rat, and sheep red blood cell membranes — J.P. Pelé, R. Calvert (1983)
• Ingested mineral fibers: elimination in human urine — P.M. Cook, G.F. Olson (1979)
• Induction and recovery of CpG site specific methylation changes in human bronchial cells after long-term exposure to carbon nanotubes and asbestos — D. Öner, M. Ghosh, et al. (2020)

Browse return to medical research.