AUTHOR=Xu Guli , Yuan Yexian , Luo Pei , Yang Jinping , Zhou Jingjing , Zhu Canjun , Jiang Qingyan , Shu Gang 

TITLE=Acute Succinate Administration Increases Oxidative Phosphorylation and Skeletal Muscle Explosive Strength via SUCNR1

JOURNAL=Frontiers in Veterinary Science

VOLUME=Volume 8 - 2021

YEAR=2022

URL=https://www.frontiersin.org/journals/veterinary-science/articles/10.3389/fvets.2021.808863

DOI=10.3389/fvets.2021.808863

ISSN=2297-1769

ABSTRACT=Endurance training and explosive strength training, with different contraction proteins and energy metabolism adaptation in skeletal muscle, are both beneficial for physical function and quality of life. Our previous study found that chronic succinate feeding enhanced the endurance exercise of mice by inducing skeletal muscle fiber-type transformation. The purpose of this study is to investigate the effect of acute succinate administration on skeletal muscle explosive strength and its potential mechanism.
 Succinate was injected to mature mice to explore the acute effect of succinate on skeletal muscle explosive strength. And C2C12 cells were used to verify the short-term effect of succinate on oxidative phosphorylation. Then the cells interfered with SUCNR1 siRNA and the SUCNR1-GKO mouse model was used for verifying the role of SUCNR1 in succinate induced muscle metabolism and expression and explosive strength. The results showed that acute injection of succinate remarkably improved the explosive strength in mice, and also decreased the ratio of NADH to NAD+, increased the mitochondrial complex enzymes activity and CK activity in skeletal muscle tissue. Similarity, treatment of C2C12 cells with succinate revealed that succinate significantly enhanced oxidative phosphorylation with increased ATP content, CK, and the activities of mitochondrial complex I and complex II, while decreased lactate content, ROS content, and NADH/NAD+ ratio. Moreover, the succinate’s effects on oxidative phosphorylation were blocked in SCUNR1-KD cells and SUCNR1-KO mice. In addition, succinate-induced explosive strength was also abolished by SUCNR1 knockout. All the results indicate that acute succinate administration increases oxidative phosphorylation and skeletal muscle explosive strength in the SUCNR1-dependent manner.