Dynamics and Half-Life of Cell-Free DNA After Exercise: Insights from a Fragment Size-Specific Measurement Approach

Area of Science:

• Molecular Biology
• Biochemistry
• Clinical Diagnostics

Background:

• Cell-free DNA (cfDNA) is found in healthy individuals and increases with physical exertion, trauma, sepsis, and cancer.
• Maintaining cfDNA homeostasis is crucial for immune function and preventing inflammation.
• Understanding cfDNA dynamics, including release and clearance, is key for its use as a clinical biomarker.

Purpose of the Study:

• To investigate the dynamics and half-life of cell-free DNA (cfDNA) fragments, specifically those sized 100-250 base pairs.
• To assess the impact of treadmill exercise on cfDNA fragment size and concentration.
• To evaluate the potential of cfDNA as a real-time biomarker for monitoring disease and treatment efficacy.

Main Methods:

• Healthy adult men (n=5) underwent a 30-minute treadmill exercise.
• Blood samples were collected at multiple time points post-exercise using specialized tubes to preserve cfDNA integrity.
• cfDNA concentration and fragment size (100-250 bp) were quantified using an electrophoresis-based system.

Main Results:

• A transient increase in 100-250 base pair cfDNA fragments was observed immediately post-exercise.
• The estimated half-life of cfDNA was determined to be 24.2 minutes.
• cfDNA levels returned to baseline within one hour after exercise cessation.

Conclusions:

• The rapid clearance of cfDNA suggests its suitability as a biomarker for dynamic physiological changes.
• This study provides insights into cfDNA fragment dynamics, aiding in the standardization of cfDNA analysis.
• Findings support the potential of cfDNA for real-time monitoring of disease progression and therapeutic responses.