Discover how a simple urine biomarker is unlocking new insights into muscle strength, bone health and fitness in young adults, paving the way for better health monitoring and interventions.
Brief reference: Urinary pentosidine as a potential biomarker of muscle and physical performance in young adult men. Image credit: Shutterstock AI
In a recent study published in Journal of Physiological Anthropologyresearchers evaluated associations between urinary pentosidine levels and physical performance and musculoskeletal status in young adult men.
Peak bone and muscle mass in early adulthood is necessary to maintain (and prevent) bone and muscle loss in late adulthood. Pentosidine is representative of the cross-linked structure of advanced glycation end products formed after oxidation of bone collagen crosslinks. Urinary pentosidine levels are known to increase with age and have been associated with various health parameters in older adults.
Serum pentosidine levels have been reported to be negatively related to muscle strength in older subjects. Urinary pentosidine is a risk factor for fracture in postmenopausal women independent of bone mineral density and age. Therefore, urinary pentosidine may be a valuable biomarker for assessing muscle mass and bone and muscle strength in adolescence and later life.
About the study
In the present study, researchers investigated the associations of urinary pentosidine with physical performance and musculoskeletal status in young adult men. They recruited 32 Japanese men aged 19–39 years. Bioelectrical impedance analysis was performed to measure fat-free mass index (FFMI), skeletal muscle and body mass.
The thickness of the anterior thigh and rectus femoris muscle of the dominant leg was measured using an ultrasound system. Further, heel stiffness index was measured by quantitative ultrasound. The team conducted four performance tests: grip strength, a timed up and go (TUG) test, a functional reach (FR) test, and a 30-second (30 seconds) chair stand test.
A digital dynamometer was used to measure grip strength of the dominant hand. The TUG test involved standing up from a chair, walking three meters forward, and returning to the chair at normal speed. The TUG score was calculated as the mean of two (TUG) tests. In the FR test, participants stood upright and extended their arms as far as possible without losing balance or leaning forward.
In the 30s chair-based test, subjects sat in a chair with arms crossed over chest, knees at 90°, and feet flat. stood up with a straight back and returned to their sitting position, maintaining smooth movement and proper form throughout. Participants were asked to repeat this task as many times as possible. Further, participants provided second urine samples for biomarker analysis.
The subjects were asked to refrain from drinking and eating from two hours before the experiment. High performance liquid chromatography was performed to measure pentosidine levels in urine. Furthermore, urinary levels of collagen type 1 N-telopeptide (NTx) and cortisol were measured using a chemiluminescent enzyme assay. Correlations between urinary biomarkers and other variables were calculated using Pearson correlation analysis.
Findings
The mean age of the participants was 24.3 years, with a mean body mass index (BMI) of 21.5 kg/m². On average, urinary pentosidine levels were 5.2 pmol/ml. The researchers observed that urinary pentosidine levels were significantly inversely correlated with FFMI, dominant grip strength, and thickness of the dominant femoris and rectus femoris muscles.
Urinary pentosidine levels did not correlate with body fat percentage. Furthermore, a marginal inverse correlation was observed between urinary pentosidine and the FR test. The researchers also noted an inverse correlation between urinary NTx levels and TUG score, although the physiological mechanisms behind this association remain unclear.
conclusions
In summary, the findings illustrate inverse associations of urinary pentosidine levels with grip strength and thickness of the rectus femoris and anterior thigh muscles of the dominant leg. Furthermore, urinary pentosidine levels showed a marginal inverse correlation with the FR test and no correlation with other physical performance parameters such as the TUG and 30s chair stand tests.
Urinary NTx levels correlated only with the TUG score and showed no correlation with bone mass or other measures, which highlights the potential limitations of NTx as a biomarker for young adults.
Limitations of the study include the inability to establish causal links given the cross-sectional nature. In addition, the study was unable to account for underlying confounders due to a limited number of parameters and small sample size. The researchers stressed that further research is needed to clarify these findings and explore the biological mechanisms involved.
Together, the findings implicate urinary pentosidine as a potential biomarker for physical performance and muscle condition in young adults. Additionally, the study highlights the potential value of reducing advanced glycation end product (AGE) accumulation through lifestyle interventions such as diet and exercise to maintain muscle health.