The aim of the present study was to investigate the effect of a triathlon (3.8 km swim, 180 km cycle, 42,2 km run) on the genomic stability of nine highly trained non-
professional athletes.
Therefore, the SCE assay, a relevant biological response marker for genotoxicity in
human biomonitoring studies [PENDZICH et al., 1997] was performed using peripheral
lymphocytes, on account of their effortless accessibility [WILKOSCY and RYNARD,
1990].
Duplicate lymphocyte cell cultures, of each participant, were incubated for 72 h (37°C, 5% CO2) according to a short-term human lymphocyte cell culture. For each participant at least 50 metaphases, containing 43-46 chromosomes were scored, to evaluate the mean SCE frequency. The number of SCEs per cell was calculated to a chromosome set of a normal diploid human cell, containing 46 chromosomes.
In the present study the alteration of SCE frequency, 48 h pre- and 24 h postrace was evaluated. As an additional endpoint Top 5 HFCs (highest five absolute SCE means) were assayed. It could be demonstrated that both the total mean SCE frequency and the mean Top 5 HFC frequency (n=9) 24 h postrace were significantly decreased (*p< 0.05) compared to 48 h prerace values. Considering the training status, a significant negative correlation between the relative SCE changes before and after the triathlon was observed for the cycling training per week (km) (r=-0.86; **p< 0.01), the running training per week (km) (r=-0.90; *p< 0.05)
as well as for the weekly net exercise training time (h) (r=-0.89; *p< 0.05). The relative changes of Top 5 HFCs before and after the race correlated significantly with the cycling training per week (km) (r=-0.79; *p< 0.05) and with the body mass index
(kg/m2) (r=-0.69; *p< 0.05). These findings suggest the existence of endogenous repair mechanisms which seem to prevent DNA damage.
Inhaltsverzeichnis (Table of Contents)
- 1. INTRODUCTION
- 2. BACKGROUND
- 2.1. Human lymphocytes
- 2.2. Cell cycle
- 2.2.1. Interphase
- 2.2.2. Mitosis
- 2.3. Sister Chromatid Exchange
- 2.4. The Correlation between strenuous endurance exercise and genotoxicity
- 3. MATERIALS AND METHODS
- 4. RESULTS AND DISCUSSION
- 5. CONCLUSION
- 6. SUMMARY
- 7. ZUSAMMENFASSUNG
Zielsetzung und Themenschwerpunkte (Objectives and Key Themes)
This diploma thesis investigates the alterations of sister chromatid exchange (SCE) frequency in peripheral lymphocytes following participation in an Ironman triathlon. The study aims to explore the relationship between strenuous endurance exercise and genotoxicity, specifically focusing on the impact of oxidative stress induced by intense physical activity on DNA.
- The effect of an Ironman triathlon on SCE frequency in lymphocytes.
- The role of reactive oxygen species (ROS) in exercise-induced DNA damage.
- The correlation between exercise intensity and the level of genotoxicity.
- The methodology of SCE assay and its application in this context.
- Analysis of potential confounding factors influencing SCE frequency.
Zusammenfassung der Kapitel (Chapter Summaries)
1. INTRODUCTION: This introductory chapter sets the stage for the research by providing a general overview of the study's focus: the impact of strenuous exercise, specifically an Ironman triathlon, on the genetic material of participants. It lays out the rationale behind investigating sister chromatid exchange (SCE) frequency as a measure of genotoxicity and introduces the key research question of whether the extreme physical demands of the event lead to detectable DNA damage.
2. BACKGROUND: This chapter provides a comprehensive overview of relevant scientific concepts. It delves into the biology of human lymphocytes, detailing their role in the immune system and their cell cycle. Crucially, it extensively explains the mechanisms of sister chromatid exchange (SCE), its significance as a biomarker of DNA damage, factors that influence SCE frequency (including both environmental and biological factors), and the methods used for its detection. A significant portion of the chapter focuses on the established link between strenuous exercise, reactive oxygen species (ROS) production, and the resulting oxidative stress and DNA damage. The section establishes a critical foundation for understanding the potential genotoxic effects of the Ironman triathlon.
3. MATERIALS AND METHODS: This chapter meticulously outlines the methodology employed in the study. It describes the subject selection criteria, including inclusion and exclusion criteria, which were crucial for ensuring the reliability of the results. The chapter details the procedures used for blood collection and the subsequent sister chromatid exchange (SCE) assay, providing a clear and precise account of the laboratory methods. It explains the statistical methods utilized for data analysis and the guidelines for microscopic assessment of the SCEs, thereby ensuring reproducibility of the study.
4. RESULTS AND DISCUSSION: This chapter presents the findings of the study, detailing the observed SCE frequencies and statistical analysis results. It analyzes the data to explore any correlations between exercise intensity, physiological parameters, and the measured SCE frequency. The discussion section interprets these findings within the context of the existing literature, explaining any discrepancies, limitations and insights gained. It critically examines whether the results support a direct link between the Ironman triathlon and increased genotoxicity as measured by SCE frequency. (Note: No content from the conclusion or final chapter is included to avoid spoilers.)
Schlüsselwörter (Keywords)
Sister chromatid exchange (SCE), Ironman triathlon, genotoxicity, oxidative stress, reactive oxygen species (ROS), lymphocytes, DNA damage, physical exercise, cell cycle, BrdU incorporation.
Frequently Asked Questions: Ironman Triathlon and Genotoxicity
What is the main topic of this study?
This diploma thesis investigates the effects of strenuous endurance exercise, specifically an Ironman triathlon, on the genetic material of participants. It focuses on whether this extreme physical activity leads to detectable DNA damage, measured by sister chromatid exchange (SCE) frequency in peripheral lymphocytes.
What methods were used to assess DNA damage?
The study used a sister chromatid exchange (SCE) assay to measure DNA damage in peripheral lymphocytes. This assay detects exchanges between sister chromatids, which are indicators of DNA damage.
What is the significance of Sister Chromatid Exchange (SCE)?
SCE is a biomarker of DNA damage. The frequency of SCEs is analyzed to determine the level of genotoxicity. Increased SCE frequency suggests higher levels of DNA damage.
What are the key themes explored in this research?
Key themes include the relationship between strenuous endurance exercise and genotoxicity, the role of reactive oxygen species (ROS) in exercise-induced DNA damage, the correlation between exercise intensity and genotoxicity, and the methodology of the SCE assay.
What is the role of reactive oxygen species (ROS) in this study?
The study explores the role of ROS, produced during intense physical activity, in causing oxidative stress and subsequent DNA damage. The researchers investigated whether increased ROS levels, due to the Ironman triathlon, led to a higher frequency of SCEs.
What are the chapter summaries?
The thesis includes an introduction setting the research context, a background chapter covering relevant biological concepts (lymphocytes, cell cycle, SCE), a materials and methods chapter detailing the study's procedures, and a results and discussion chapter presenting and interpreting the findings. The conclusion and summary chapters are not detailed here.
What were the objectives of the study?
The study aimed to determine the effect of an Ironman triathlon on SCE frequency, to investigate the role of ROS in exercise-induced DNA damage, to explore the correlation between exercise intensity and genotoxicity, to describe the SCE assay methodology, and to analyze potential confounding factors influencing SCE frequency.
What type of participants were involved in the study?
The study describes the subject selection criteria, including inclusion and exclusion criteria, used to ensure reliable results. These details are specified in the "Materials and Methods" chapter.
What kind of statistical analysis was used?
The "Materials and Methods" chapter details the statistical methods employed for analyzing the data obtained from the SCE assay.
What are the keywords associated with this research?
Keywords include sister chromatid exchange (SCE), Ironman triathlon, genotoxicity, oxidative stress, reactive oxygen species (ROS), lymphocytes, DNA damage, physical exercise, cell cycle, and BrdU incorporation.
Where can I find more detailed information?
The full text of the diploma thesis would provide comprehensive details on the methodology, results, and discussion of the findings.
- Quote paper
- Mag.rer.nat. Marlies Meisel (Author), 2007, Alterations of the Sister Chromatid Exchange frequency in peripheral lymphocytes caused by an Ironman triathlon, Munich, GRIN Verlag, https://www.grin.com/document/86371
