Noninvasive markers of oxidative DNA stress, RNA degradation and protein degradation are differentially correlated with resting metabolic rate and energy intake in children and adolescents.
Urinary excreted RNA and DNA catabolites are used as noninvasive markers for metabolic processes: 8-oxo-2'-deoxyguanosine (8-oxodG) potentially represents oxidative stress to DNA/deoxyribonucleotidetriphosphate pool, modified ribonucleoside pseudouridine (psi) originating mainly from degraded rRNA and tRNA reflects RNA turnover. Modified amino acid gamma-carboxyglutamic acid (Gla) stems from degraded proteins reflecting turnover of proteins. Aim of the present study was to investigate (44 healthy males, 3-18 y) how excretion rates of 8-oxodG, psi, and Gla are related to resting metabolic rate and energy intake. Excretion rates of 8-oxodG (pmol/kg/d), psi (micromol/kg/d), and Gla (micromol/kg/d) were significantly correlated with resting metabolic rate (kJ/kg/d): r = 0.108 (p = 0.029), 0.691 and 0.552 (p < 0.0001), respectively. Excretion rates of 8-oxodG, psi, and Gla were also significantly correlated with energy intake (kJ/kg/d): r = 0.108 (p = 0.036), 0.602 and 0.462 (p < 0.0001). 8-oxodG and Gla excretion was significantly correlated with psi excretion: r = 0.174 (p = 0.005) and 0.709 (p < 0.0001). These results indicate close relationships between whole-body RNA and protein degradation and metabolic rate. The relationship between 8-oxodG excretion and metabolic rate, however, is less strong suggesting that factors other than metabolic rate considerably affect the oxidative stress to DNA.
Topp
Heinrich
H
Neonatology, University Children's Hospital, 17487 Greifswald, Germany.
Fusch
Gerhard
G
Schöch
Gerhard
G
Fusch
Christoph
C
D015055:1-Carboxyglutamic Acid / Q000652:urine*; D000080242:8-Hydroxy-2'-Deoxyguanosine; D000293:Adolescent; D001481:Basal Metabolism / Q000502:physiology*; D015415:Biomarkers / Q000652:urine; D015992:Body Mass Index; D001835:Body Weight / Q000502:physiology; D002648:Child; D002675:Child, Preschool; D004249:DNA Damage / Q000502:physiology; D003849:Deoxyguanosine / Q000031:analogs & derivatives* / Q000652:urine; D002149:Energy Intake / Q000502:physiology*; D006801:Humans; D008297:Male; D018384:Oxidative Stress / Q000502:physiology*; D011506:Proteins / Q000378:metabolism; D011560:Pseudouridine / Q000652:urine*; D020871:RNA Stability / Q000502:physiology
D015415:Biomarkers; D011506:Proteins; D011560:Pseudouridine; D015055:1-Carboxyglutamic Acid; D000080242:8-Hydroxy-2'-Deoxyguanosine; D003849:Deoxyguanosine