Measurement of urinary 8-oxo-7,8-dihydro-2-deoxyguanosine in a novel point-of-care testing device to assess oxidative stress in children

Abstract

Background: 8-oxo-7,8-dihydro-2-deoxyguanosine (8-oxodG), also known as 8-hydroxy-2'-deoxyguanosine (8-OHdG), is an oxidatively damaged nucleobases of DNA and is excreted into urine. Therefore, its urinary level is used as a sensitive marker for oxidative stress (OS). Although it can be measured by enzyme-linked immunosorbent assay (ELISA), its application to clinical pediatrics remains limited. Recently, a novel automatic analyzer (model no. ICR-001: Techno Medica Co., Ltd., Japan) has been developed for point-of-care testing (POCT) to measure urinary 8-oxodG. We verified the reliability of the value of urinary 8-oxodG measured by this novel analyzer and to set the age-related reference intervals.

Method: We obtained random urine samples from 100 healthy Japanese adults and 157 healthy Japanese children aged 0-15years. Urinary 8-oxodG was determined using two methods: competitive immunochromatography using a novel automatic analyzer (ICR-001) and another was ELISA.

Results: Both urinary 8-oxodG and urinary creatinine measured by ICR-001 correlated well with those measured by ELISA (r(s)=0.945, p<0.0001) and an enzymatic method (r(s)=0.988, p<0.0001). Age-related reference for 8-oxodG corrected by creatinine were highest in the youngest subjects and decreased until adolescence, consistent with published data by ELISA.

Conclusion: A new automatic analyzer that measures urinary 8-oxodG can be used as a POCT for the assessment of OS levels in children.