Effect of High Fat Diet and Endurance Training on the Gene Expression of Sarco/Endoplasmic Reticulum ATPase2 (SERCA2) and Ryanodine Receptor2 (RYR2) under Near-Thermoneutrality in Inguinal Adipose Tissue of Mice

Abstract

Introduction: Non shivering thermogenesis is partly yielded by a futile-calcium-cycle mechanism that is regulated by Sarco/Endoplasmic Reticulum ATPase2 (SERCA2) and Ryanodine Receptor2 (RYR2). This study aimed to investigate the effect of a high-fat diet and endurance training under near-thermoneutrality (in which humans live) on the gene expression of SERCA2 and RYR2 in inguinal subcutaneous adipose tissue in mice. Material & Methods: A total of 28 C57BL/6 male mice were assigned into four groups of seven animals per group. The groups included 1) control 2), high-fat diet (HFD), 3) endurance training (ET), and 4) HFD-ET. The environment temperature was set out at 26°C. The mice in the HFD group were fed a high-fat diet (fat=42%) for 12 weeks. The mice in the ET group underwent ET on the treadmill for six weeks. The mice of the HFD-ET had both the HFD and ET. The real-time-PCR method was used to measure the gene expression of SERCA2a, SERCA2b, and RYR2 in adipose tissue. (Ethic code: ABRU.AC.IR/15664-96.44) Findings: Two-way ANOVA showed that the relative gene expression of SERCA2a, SERCA2b, and RYR2 were not significantly affected by HFD, ET, and HFD-ET (P>0.05). Discussion & Conclusion: The HFD and ET did not change the regulatory proteins of the futile-calcium-cycle under near-thermoneutrality in the beige adipose tissue. Therefore, it was speculated that the non-shivering thermogenesis that is induced by these conditions might occur independently of futile-cycle-calcium.

Keywords

• beige adipose tissue
• futile cycle
• obesity
• thermogenesis