TY - JOUR
T1 - Human and methodological sources of variability in the measurement of urinary 8-oxo-7,8-dihydro-2'-deoxyguanosine
AU - Barregard, Lars
AU - Møller, Peter
AU - Henriksen, Trine
AU - Mistry, Vilas
AU - Koppen, Gudrun
AU - Rossner, Pavel
AU - Sram, Radim J
AU - Weimann, Allan
AU - Poulsen, Henrik E
AU - Nataf, Robert
AU - Andreoli, Roberta
AU - Manini, Paola
AU - Marczylo, Tim
AU - Lam, Patricia
AU - Evans, Mark D
AU - Kasai, Hiroshi
AU - Kawai, Kazuaki
AU - Li, Yun-Shan
AU - Sakai, Kazuo
AU - Singh, Rajinder
AU - Teichert, Friederike
AU - Farmer, Peter B
AU - Rozalski, Rafal
AU - Gackowski, Daniel
AU - Siomek, Agnieszka
AU - Saez, Guillermo T
AU - Cerda, Concha
AU - Broberg, Karin
AU - Lindh, Christian
AU - Hossain, Mohammad Bakhtiar
AU - Haghdoost, Siamak
AU - Hu, Chiung-Wen
AU - Chao, Mu-Rong
AU - Wu, Kuen-Yuh
AU - Orhan, Hilmi
AU - Senduran, Nilufer
AU - Smith, Raymond J
AU - Santella, Regina M
AU - Su, Yali
AU - Cortez, Czarina
AU - Yeh, Susan
AU - Olinski, Ryszard
AU - Loft, Steffen
AU - Cooke, Marcus S
PY - 2013/6/20
Y1 - 2013/6/20
N2 - AIMS: Urinary 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) is a widely used biomarker of oxidative stress. However, variability between chromatographic and ELISA methods hampers interpretation of data, and this variability may increase should urine composition differ between individuals, leading to assay interference. Furthermore, optimal urine sampling conditions are not well defined. We performed inter-laboratory comparisons of 8-oxodG measurement between mass spectrometric-, electrochemical- and ELISA-based methods, using common within-technique calibrants to analyze 8-oxodG-spiked phosphate-buffered saline and urine samples. We also investigated human subject- and sample collection-related variables, as potential sources of variability.RESULTS: Chromatographic assays showed high agreement across urines from different subjects, whereas ELISAs showed far more inter-laboratory variation and generally overestimated levels, compared to the chromatographic assays. Excretion rates in timed 'spot' samples showed strong correlations with 24 h excretion (the 'gold' standard) of urinary 8-oxodG (rp 0.67-0.90), although the associations were weaker for 8-oxodG adjusted for creatinine or specific gravity (SG). The within-individual excretion of 8-oxodG varied only moderately between days (CV 17% for 24 h excretion and 20% for first void, creatinine-corrected samples).INNOVATION: This is the first comprehensive study of both human and methodological factors influencing 8-oxodG measurement, providing key information for future studies with this important biomarker.CONCLUSION: ELISA variability is greater than chromatographic assay variability, and cannot determine absolute levels of 8-oxodG. Use of standardized calibrants greatly improves intra-technique agreement and, for the chromatographic assays, importantly allows integration of results for pooled analyses. If 24 h samples are not feasible, creatinine- or SG-adjusted first morning samples are recommended.
AB - AIMS: Urinary 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) is a widely used biomarker of oxidative stress. However, variability between chromatographic and ELISA methods hampers interpretation of data, and this variability may increase should urine composition differ between individuals, leading to assay interference. Furthermore, optimal urine sampling conditions are not well defined. We performed inter-laboratory comparisons of 8-oxodG measurement between mass spectrometric-, electrochemical- and ELISA-based methods, using common within-technique calibrants to analyze 8-oxodG-spiked phosphate-buffered saline and urine samples. We also investigated human subject- and sample collection-related variables, as potential sources of variability.RESULTS: Chromatographic assays showed high agreement across urines from different subjects, whereas ELISAs showed far more inter-laboratory variation and generally overestimated levels, compared to the chromatographic assays. Excretion rates in timed 'spot' samples showed strong correlations with 24 h excretion (the 'gold' standard) of urinary 8-oxodG (rp 0.67-0.90), although the associations were weaker for 8-oxodG adjusted for creatinine or specific gravity (SG). The within-individual excretion of 8-oxodG varied only moderately between days (CV 17% for 24 h excretion and 20% for first void, creatinine-corrected samples).INNOVATION: This is the first comprehensive study of both human and methodological factors influencing 8-oxodG measurement, providing key information for future studies with this important biomarker.CONCLUSION: ELISA variability is greater than chromatographic assay variability, and cannot determine absolute levels of 8-oxodG. Use of standardized calibrants greatly improves intra-technique agreement and, for the chromatographic assays, importantly allows integration of results for pooled analyses. If 24 h samples are not feasible, creatinine- or SG-adjusted first morning samples are recommended.
KW - 8-Hydroxy-2'-Deoxyguanosine
KW - Adult
KW - Artifacts
KW - Buffers
KW - Deoxyguanosine/analogs & derivatives
KW - Female
KW - Head and Neck Neoplasms/urine
KW - Humans
KW - Male
KW - Middle Aged
KW - Reference Standards
KW - Reproducibility of Results
KW - Sodium Chloride
KW - Solutions
KW - Urinalysis/standards
KW - Young Adult
UR - https://www.scopus.com/pages/publications/84878591374
U2 - 10.1089/ars.2012.4714
DO - 10.1089/ars.2012.4714
M3 - Journal article
C2 - 23198723
SN - 1523-0864
VL - 18
SP - 2377
EP - 2391
JO - Antioxidants & Redox Signaling
JF - Antioxidants & Redox Signaling
IS - 18
ER -