Biomarkers of mitochondrial stress and DNA damage during pediatric catheter-directed neuroangiography - a prospective single-center study.

Abstract

Neuroangiography represents a critical diagnostic and therapeutic imaging modality whose associated radiation may be of concern in children. The availability of in vivo radiation damage markers would represent a key advancement for understanding radiation effects and aid in the development of radioprotective strategies. Determine if biomarkers of cellular damage can be detected in the peripheral blood mononuclear cells (PBMC) of children undergoing neuroangiography. Prospective single-site study of 27 children. Blood collected pre and post neuroangiography, from which PBMC were isolated and assayed for biomarkers of mitochondrial stress (mitochondrial membrane potential (MMP), reactive oxygen species (ROS), and mitochondrial DNA (mtDNA)) and DNA damage (γH2AX). Dose response of biomarkers vs. radiation dose was analyzed using linear regressions. The cohort was divided into higher (HD) and lower dose (LD) groups and analyzed using linear mixed models and compared using Welch's t-tests. No biomarker exhibited a dose-dependent response following radiation (γH2AX: R2 = 0.0012, P = 0.86; MMP: R2 = 0.016, P = 0.53; mtDNA: R2 = 0.10, P = 0.11; ROS: R2 = 0.0023, P = 0.81). Groupwise comparisons showed no significant differences in γH2AX or ROS after radiation (γH2AX: LD: 0.6 ± 6.0, P = 0.92; HD: -7.5 ± 6.3 AU, P = 0.24; ROS: LD: 1.3 ± 2.8, P = 0.64; HD: -3.6 ± 3.0 AU, P = 0.24). Significant changes were observed to mitochondrial markers MMP (-53.7 ± 14.7 AU, P = 0.0014) and mtDNA (-1.1 ± 0.4 AU, P = 0.0092) for HD, but not the LD group (MMP: 26.1 ± 14.7 AU, P = 0.090; mtDNA: 0.2 ± 0.4, P = 0.65). Biomarkers of mitochondrial stress in PBMC were identified during pediatric neuroangiography and warrant further investigation for radiation biodosimetry. However, isolating radiation-specific effects from those of procedural stress and general anesthesia requires further investigation.