Effect of sera from elite athletes on cytokine secretion and insulin signaling in preadipocytes and skeletal muscle cells

Sara Alheidous; Shamma Al-Muraikhy; Nasser Rizk; Maha Sellami; Francesco Donati; Francesco Botre; Layla Al-Mansoori; Mohamed A Elrayess

doi:10.3389/fmolb.2022.943034

Effect of sera from elite athletes on cytokine secretion and insulin signaling in preadipocytes and skeletal muscle cells

Front Mol Biosci. 2022 Nov 24:9:943034. doi: 10.3389/fmolb.2022.943034. eCollection 2022.

Authors

Sara Alheidous¹, Shamma Al-Muraikhy¹, Nasser Rizk^{1

2}, Maha Sellami³, Francesco Donati⁴, Francesco Botre^{4

5}, Layla Al-Mansoori¹, Mohamed A Elrayess^{1

6}

Affiliations

¹ Biomedical Research Center, Qatar University, Doha, Qatar.
² Biomedical Sciences Department, College of Health Sciences, QU Health, Qatar University, Doha, Qatar.
³ Physical Education Department (PE), College of Education, Qatar University, Doha, Qatar.
⁴ Federazione Medico Sportiva Italiana (FMSI), Rome, Italy.
⁵ REDs-Research and Expertise in AntiDoping Sciences, University of Lausanne, Lausanne, Switzerland.
⁶ College of Pharmacy, QU Health, Qatar University, Doha, Qatar.

Abstract

Introduction: The immunomodulatory effect of physical activity can impact insulin signaling differentially in adipose tissues and skeletal muscle cells, depending on sport intensity. In this study, the effect of serum from elite athletes with varying endurance levels and playing different power sports on cytokine secretion and insulin signaling in preadipocyte and skeletal muscle cell lines was investigated. Methods: Preadipocytes (3T3-L1) and skeletal muscle cells (C2C12) were cultured in media containing pooled sera from elite athletes who play high-endurance (HE), high-power (HP), or low-endurance/low-power (LE/LP) sports for 72 h. Secreted cytokines (IL-6 and TNF-alpha) were assessed in the supernatant, and insulin signaling phosphoproteins levels were measured in lysates following treatment using cells multiplex immunoassays. Results: Sera from LE/LP and HP induced TNF-α secretion in C2C12, while serum from HE reduced IL-6 secretion compared to non-athlete serum control. All elite athlete sera groups caused decreased insulin sensitivity in 3T3-L1 cells, whereas in C2C12 cells, only HE athlete serum reduced insulin signaling, while LE/LP and HP caused increased insulin sensitivity. Conclusion: Sera from elite athletes of different sport disciplines can affect the inflammatory status and insulin signaling of preadipocytes and myoblasts differently, with risk of developing insulin resistance. Furthermore, investigation of the functional relevance of these effects on exercise physiology and pathophysiology is warranted.

Keywords: elite athletes; high-endurance sports; high-power sports; inflammation; insulin signaling; preadipocytes; skeletal muscle cells.