Cell-Free Plasma DNA as a Novel Marker of Aseptic Inflammation Severity Related to Exercise Overtraining

Abstract

Background: Circulating free plasma DNA is implicated in conditions associated with tissue injury, including exercise-induced inflammation, and thus is a potential marker for athletic overtraining. Methods: We measured free plasma DNA along with C-reactive protein (CRP), creatine kinase (CK), and uric acid (UA) in 17 recreationally trained men participating in a 12-week resistance training regimen (8 resistance multi-joint exercises selected to stress the entire musculature: bench press, squat, leg press, snatch, hang clean, dead lifts, barbell arm curls, and rowing), consisting of 4 training periods (t1, t2, t3, and t4). Results: Plasma DNA concentrations increased markedly after t1, t2, and t3 and returned to baseline after t4. There were substantial differences between t2 and t1 and between t3 and t2 plasma DNA concentrations. CRP increased by 300% after t2 and by 400% after t3 (there was no difference between t2 and t3 CRP values) compared with baseline (t0). CK increased only after t3. UA increased after t2 and t3, with a greater increase after t3. Conclusions: This study demonstrates that, after chronic excessive resistance exercise, plasma DNA concentrations increase in proportion to training load, suggesting that plasma DNA may be a sensitive marker for overtraining-induced inflammation.

High‐Intensity Resistance Training with Insufficient Recovery Time Between Bouts Induce Atrophy and Alterations in Myosin Heavy Chain Content in Rat Skeletal Muscle

“…Compared to the Co group, the Tr group exhibited a significant (P < 0.05) decrease in pure fiber IIA and IID CSA in the plantaris DR portion; there was also a tendency for pure fiber I and IIB CSA to decrease in this portion (P ¼ 0.08 and P ¼ 0.09, respectively). Our results are consistent with several studies which show a predominance of catabolic condition (Seene et al, 1999;Petibois et al, 2000;Seene et al, 2004) in situations with a persistent combination of excessive overload plus inadequate recovery (Jamurtas et al, 2000;Fatouros et al, 2006). Although the molecular events that underlie our findings remain unknown, these observations raise questions as to what signals and cellular conditions initiate muscle mass changes during overtraining conditions.…”

“…Thus, progression from the benign adaptive microtrauma stage may exacerbate the initial injury (Stone et al, 1991) resulting in a subclinical injury in the overtrained athlete. Muscle injury induces a reduction in strength (Fatouros et al, 2006) due to extensive muscle damage (Seene et al, 1999), swelling in the injured area, soreness, edema (Jamurtas et al, 2000;Fatouros et al, 2006), and local inflammatory response (Smith, 2004). Also, Petibois et al (2003) demonstrated that overtrained individuals have higher amino acid and lower protein blood accumulation in response to exercise than welltrained individuals.…”

Changes in cell free DNA during a college soccer season

“…However, few investigations of cf-DNA, as it relates to exercise and/or training, have been conducted. Recent studies of cf-DNA have explored the acute response of cf-DNA after a single bout of exercise [12][13][14][15][16][17] , as well as chronic changes in cf-DNA concentrations with resistance training 18 . These initial inquiries of post-exercise cf-DNA concentrations and training have suggested that cf-DNA may provide benefits over other markers of tissue damage and inflammation such as creatine kinase (CK) and C-reactive protein (CRP), for inclusion in a LTAMP.…”

Circulating miR-21, miR-146a and Fas ligand respond to postmenopausal estrogen-based hormone replacement therapy – A study with monozygotic twin pairs

“…The physiological role of sFasL is controversial since it has been reported to induce non-apoptotic signals, possibly including NF-kβ-mediated stimulation of cell proliferation, survival or inflammation within an elevated cytokine milieu (Suda, et al 1997, Mogi, et al 2001, Serrao, et al 2001). In addition to FasL, circulating cell free DNA (cfDNA) has quite recently been discovered as a potential marker of inflammation, apoptosis, senescence and malignant conditions (Stroun, et al 1987, Fatouros, et al 2006, Jylhava, et al 2012). …”