Category: Preclinical Development
Purpose: There is little information on metabolic responses to exercise training of female adolescent volleyball athletes. Conventional biological markers, hormonal markers and immunological markers have been learned to evaluate the physical status in volleyball athletes with exercise training. However, these markers are usually preselected based on some expected hypothesis, could not sensitively reflect all physiological differences and would be unable to explain the interaction between a variety of the metabolites. This study aims to obtain metabolite markers in serum and urine of female adolescent volleyball athletes within 2-week strength-endurance training and to gain mechanistic insights into the effect of training using metabolomics approach coupled with biochemical analysis.
Methods: Twelve female adolescent volleyball athletes were recruited for 2-week strength-endurance training. Differential serum and urine metabolic profiles between pre- and post-training were investigated by gas chromatograph-mass spectrometry (GC-MS) and data further underwent orthogonal partial least-squares (OPLS) analysis. Multivariate statistics was applied to process the data followed by the identification of the potential biomarkers. Biochemical parameters were analyzed using specific assays or were measured using an automated biochemistry analyzer.
Results: Exposure to the 2-week strength-endurance training led to a significant increase in cortisol (197.27±34.29 to 282.05±44.99 ng/mL, p=0.004), blood urea nitrogen (4.70±0.26 to 6.32±0.44 mmol/L, p=0.000), malondialdehyde (2.12±0.14 to 2.61±0.52 nmol/mL, p=0.030) and superoxide dismutase (23.98±0.80 to 25.20±0.50 U/mL, p=0.000) and to a decrease in testosterone (56.69±7.98 to 42.91±6.92 nmol/L, p=0.007) level in serum in comparison with the pre-training group. There were also a slight and non-significant increase in creatine kinase and lactic dehydrogenase levels with exercise training (p >0.05). Additionally, the metabolic perturbations were attributed to shifts in various organic acids, amino acids, fatty acids, and other compounds in serum and urine within training. The altered metabolites included increased alanine, valine, glycerol, isoleucine, glycine, serine, threonine, 5-oxoproline, glutamic acid, ornithine, palmitic acid, linoleic acid, oleic acid, and octadecanoic acid and decreased threonic acid, aspartic acid, and critic acid in serum; and increased glycine, threonine, threonic acid, phosphoric acid, myo-inositol and uric acid and decreased valine, leucine, 5-oxoproline, ornithine, aconitic acid, citric acid, fumaric acid, and histidine in urine of post-training group as compared with pre-training group.
Conclusion: By means of high throughput metabolomics, the variations in serum and urine between pre-training and post-training groups were well differentiated. The 2-week strength-endurance training affected the balance of hormone adjustment and caused oxidative stress response in female adolescent volleyball athletes, no significant changes of muscle damage markers were found. Meanwhile, female athletes were slightly protected from exercise-induced oxidative stress. During training, female athletes showed an increased propensity to oxidize lipids as the major energy source and conserve protein metabolism. Disordered urea cycle and inositol metabolism also occurred with training.
Chunming Lyu– Research Scientist, Shanghai Zhulian Intelligent Technology Co., Ltd., Shanghai, Shanghai, China (People's Republic)
Guigang Zeng– Shanghai, Shanghai, China (People's Republic)
Shen Zhang– Shanghai, Shanghai, China (People's Republic)
Hai Wei– Shanghai University of Traditional Chinese Medicine, Shanghai, Shanghai, China (People's Republic)