Reliability of a Fully Automated Interpretation of γ -H2AX Foci in Lymphocytes of Moderately Trained Subjects under Resting Conditions

Juliane Heydenreich; Christoph Otto; Frank Mayer; Anja Carlsohn

doi:10.1155/2014/478324

Reliability of a Fully Automated Interpretation of γ -H2AX Foci in Lymphocytes of Moderately Trained Subjects under Resting Conditions

J Nutr Metab. 2014:2014:478324. doi: 10.1155/2014/478324. Epub 2014 Jul 24.

Authors

Juliane Heydenreich¹, Christoph Otto², Frank Mayer², Anja Carlsohn³

Affiliations

¹ Sports Medicine and Sports Orthopaedics, University Outpatient Clinic, University of Potsdam, 14469 Potsdam, Germany ; ZIEL-Research Centre for Nutrition and Food Sciences, Munich Technical University, 85354 Freising-Weihenstephan, Germany.
² Sports Medicine and Sports Orthopaedics, University Outpatient Clinic, University of Potsdam, 14469 Potsdam, Germany.
³ Sports Medicine and Sports Orthopaedics, University Outpatient Clinic, University of Potsdam, 14469 Potsdam, Germany ; Institute of Health Science, Schwäbisch Gmünd University of Education, 73529 Schwäbisch Gmünd, Germany.

Abstract

Background. Analysis of γ-H2AX foci is a promising approach to evaluate exercise-induced DNA damage. However, baseline levels and day-to-day variability of γ-H2AX foci have not been investigated in healthy subjects at rest. Methods. Blood was taken from eight moderately trained healthy males (29 ± 3 yrs, 1.84 ± 0.03 m, and 85 ± 6 kg) at two separate days (M1/M2) after 24-hour exercise cessation. Number of γ-H2AX foci per 100 lymphocytes (N), number of foci per affected lymphocyte (NAL), percentage of affected lymphocytes (PAL), and diameter (D) of γ-H2AX foci were analyzed (mean ± SD). Differences between M1 and M2 were analyzed using paired t-tests (α = 0.05). Day-to-day variability was evaluated by calculating the coefficients of variation (CV%), bias, and limits of agreement (LoA). Results. There were no statistically significant differences between M1 (N: 7.6 ± 4.4, NAL: 1.2 ± 0.2, PAL: 5.9 ± 2.6%, and D: 0.63 ± 0.07) and M2 (N: 8.4 ± 4.6, NAL: 1.3 ± 0.1, PAL: 6.9 ± 4.2%, and D: 0.66 ± 0.06). CV was calculated to be 98.5% (N), 88.9% (PAL), 11.3% (NAL), and 8.0% (D). Bias (LoA) was 0.75 (-15.2/13.7), -0.02 (-0.36/0.33), -1.0 (-11.9/9.9), and -0.04 (-0.16/0.09), respectively. Conclusions. Background level in healthy subjects is approximately 0.07 to 0.09 γ-H2AX foci/cell. NAL and D are reliable measures.