Exercise-Induced Myokine Response Following 75-km Cycling

ASU Author/Contributor (non-ASU co-authors, if there are any, appear on document)
Brandon Tolbert (Creator)
Institution
Appalachian State University (ASU )
Web Site: https://library.appstate.edu/
Advisor
Kevin Zwetsloot

Abstract: Abstract Myokine is a term referring to a variety of cytokines or chemokines that are produced and released by myocytes in response to skeletal muscle contractions. The myokine response to prolonged exercise is not well known. Therefore, the purpose of this study was to investigate the myokine response to prolonged exercise by measuring fifteen different myokines in skeletal muscle biopsies. Trained cyclists (N=14) participated in a 75-­-km cycling time trial, with muscle samples from the vastus lateralis taken before and after the exercise bout. The skeletal muscle biopsy samples were analyzed for 15 myokines including: APLN, CX3CL1, BDNF, EPO, SPARC, LIF, IL15, GDF8, FABP3, Irisin, FSTL1, OSM, IL6, FGF21, and OSTN. These myokines were analyzed with a magnetic bead-­-based multiplex assay. The 75km cycling exercise bout significantly increased skeletal muscle Interleukin-­-15, Oncostatin M, and Fractalkine protein levels from, 0.043±0.008 to 0.055±0.021, 0.0014±0.002 to 0.0059±0.004 and 4.45±0.46 to 4.60±0.54 pg/µg, respectively (all p<0.05). Apelin protein levels exhibited a decrease from 3.95±1.18 to 3.33±1.21 pg/µg (p<0.05). No statistically significant difference was observed for FSTL1, IL6, SPARC, BDNF, FGF21, LIF, or OSTN. Erythropoietin, Irisin, and Myostatin were all below detectable limits for the assay, and Fatty Acid-­-Binding Protein 3 exhibited values above the detection limit. Over the last couple decades, our knowledge of cytokine proteins has increased considerably as has our understanding of their functions and regulatory mechanisms. However, with few exceptions, our knowledge is still relatively limited as to the mechanism and regulation of cytokine production during exercise, especially in the muscle tissue. Consequently, research is still ongoing for many of the tested proteins to determine their function when it comes to skeletal muscle adaptation.

Additional Information

Publication
Thesis
Tolbert, B (2016) "Exercise-Induced Myokine Response Following 75-km Cycling" Unpublished Honor's Thesis. Appalachian State University, Boone, NC
Language: English
Date: 2016

Email this document to