Measurement of 1,5-anhydroglucitol in blood and saliva: from non-targeted metabolomics to biochemical assay.
J Transl Med
; 14(1): 140, 2016 05 18.
Article
em En
| MEDLINE
| ID: mdl-27188855
ABSTRACT
BACKGROUND:
Diabetes testing using saliva, rather than blood and urine, could facilitate diabetes screening in public spaces. We previously identified 1,5-anhydro-D-glucitol (1,5-AG) in saliva as a diabetes biomarker. The Glycomark™ assay kit is FDA approved for 1,5-AG measurement in blood. Here we evaluated its applicability for 1,5-AG quantification in saliva.METHODS:
Using pooled saliva samples, we validated Glycomark™ assay use with a RX Daytona(+) clinical chemistry analyser. We then used this set-up to analyse 82 paired blood and saliva samples from a diabetes case-control study, for which broad mass spectrometry-based characterization of the blood and saliva metabolome was also available. Osmolality was measured to account for potential variability in saliva samples.RESULTS:
The technical variability of the read-outs for the pooled saliva samples (CV = 2.05 %) was comparable to that obtained with manufacturer-provided blood surrogate quality controls (CV = 1.38-1.8 %). We found a high correlation between Glycomark assay and mass spectrometry measurements of serum 1,5-AG (r(2) = 0.902), showing reproducibility of the non-targeted metabolomics results. The significant correlation between the osmolality measurements performed at two independent platforms with the time interval of 2 years (r(2) = 0.887), also indicates the sample integrity. The assay read-out for saliva was not correlated with the mass spectrometry-based 1,5-AG saliva measurements. Comparison with the full saliva metabolome revealed a high correlation of the saliva assay read-outs with galactose.CONCLUSIONS:
Glycomark™ assay read-outs for saliva were stable and replicable. However, the signal was dominated by galactose, which is biochemically similar to 1,5-AG and absent in blood. Adapting the 1,5-AG kit for saliva analysis will require enzymatic depletion of galactose. This should be feasible, since the assay already includes a similar step for glucose depletion from blood samples.
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Base de dados:
MEDLINE
Assunto principal:
Saliva
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Bioensaio
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Desoxiglucose
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Metabolômica
Tipo de estudo:
Observational_studies
Limite:
Adult
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Aged
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Female
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Humans
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Male
/
Middle aged
Idioma:
En
Revista:
J Transl Med
Ano de publicação:
2016
Tipo de documento:
Article
País de afiliação:
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