Significant increase in prostaglandin E-major urinary metabolite with physical exercise suggesting muscle inflammation

Abstract

Introduction: Prostaglandin E-major urinary metabolite (PGE-MUM) may be a good biomarker of inflammation and useful in monitoring diseases, without the necessity of invasive sampling. To see whether inflammation in muscles occurs during physical exercise, the influence of physical exercise on urinary PGE-MUM levels was analyzed in high school boys belonging to a soccer club.

Materials and methods: Void urine samples were obtained before and after physical exercises 1 (mild exercise) and 2 (repeated mild exercise). To avoid the influence of a change in urinary volume, PGE-MUM values (ng/mL) were corrected by the concentration of urinary creatinine (mg/dL) and expressed as PGE-MUM·Cr (µg/g creatinine). Urinary total protein·Cr (µg/g creatinine) and L-type fatty acid-binding protein·Cr (µg/g creatinine) (L-FABP·Cr) were compared with PGE-MUM·Cr.

Results: The PGE-MUM·Cr level increased significantly immediately after playing soccer (regular ‘mild’ exercise) in exercise study 1 or running (repeated mild exercise) in exercise study 2, but declined the next morning. PGE-MUM (ng/mL) levels in both exercises strongly correlated (Spearman correlation coefficient, ρ = 0.728; 0.480, respectively) with urinary creatinine (mg/dL) thought to be derived from muscle exercise.

Conclusion: The early increase in the PGE-MUM·Cr level just after physical exercise may reflect muscle damage and inflammation caused by the exercise.

KEYWORDS:

• Biomarker
• muscle inflammation
• prostaglandin E-major urinary metabolite
• physical exercise
• urine
• urinary creatinine

Acknowledgments

The authors are grateful to all students for allowing them to perform this study. The authors would like to thank Chieko Takano, a nurse teacher and head of the wellness center of Kiryu Daiici High School, for collecting and summarizing data from soccer club members in general annual health checkups.

Author contributions

I.O. and H.O. firstly conceived the present work.

I.O. developed and precisely designed the project.

I.O., H.K., K.H., S.S., K.S., G.T., and K.U. collected and analyzed the data and samples, and offered suggestions for the study.

K.U. performed laboratory work to measure urinary markers in this study.

I.O, K.S., and N.I. analyzed data using related software.

R.S., a high school doctor obtained general health check data of participants, analyzed, and confirmed their healthy state for the present study.

R.S. and H.O. critiqued the study and made suggestions, particularly on the methods and interpretation of the results.

I.O. wrote the main text and prepared figures.

All members reviewed and approved the final manuscript.

Disclosure statement

K.U., an employee of Fujirebio Inc., the company that has the commercial rights to PGE-MUM tests, measured PGE-MUM values blinded to participant data. I.O. received a research grant for part of this study from Fujirebio Inc. The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publications.

Data Availability Statement

All relevant data are within the manuscript. Supplementary figures are available. All raw data for the information is available. Search on 4TU Research Data https://doi.org/10.4121/21778979

Additional information

Funding

This study was supported by an annual research grant for the study from Kiryu University and partly supported by a research grant, Kiryu 2018, 2019 from Fujirebio Inc.