Identification of porcine fast/slow myogenic exosomes and their regulatory effects on lipid accumulation in intramuscular adipocytes  

作　　者：Tiantian Zhao Tingting Tian He Yu Chaoyue Cao Ziyi Zhang Zhaozhao He Zeqiang Ma Rui Cai Fengna Li Weijun Pang 

机构地区：[1]Laboratory of Animal Fat Deposition&Muscle Development,College of Animal Science and Technology,Northwest A&F University,Yangling 712100,Shaanxi,China [2]Laboratory of Animal Nutritional Physiology and Metabolic Process,Key Laboratory of Agro‑ecological Processes in Subtropical Region,Institute of Subtropical Agriculture,Chinese Academy of Sciences,Changsha 410125,Hunan,China

出　　处：《Journal of Animal Science and Biotechnology》2024年第4期1512-1527,共16页畜牧与生物技术杂志（英文版）

基　　金：supported by the National Natural Science Foundation of China (32272847, U22A20516);the Key Research and Development Program of Shaanxi Province (2022ZDLNY01-04);the China Agriculture Research System of MOF and MARA (CARS-35)。

摘　　要：Background Pork quality is affected by the type of muscle fibers, which is closely related to meat color, tenderness and juiciness. Exosomes are tiny vesicles with a diameter of approximately 30–150 nm that are secreted by cells and taken up by recipient cells to mediate communication. Exosome-mediated muscle-fat tissue crosstalk is a newly discovered mechanism that may have an important effect on intramuscular fat deposition and with that on meat quality. Various of adipose tissue-derived exosomes have been discovered and identified, but the identification and function of muscle exosomes, especially porcine fast/slow myotube exosomes, remain unclear. Here, we first isolated and identified exosomes secreted from porcine extensor digitorum longus(EDL) and soleus(SOL), which represent fast and slow muscle, respectively, and further explored their effects on lipid accumulation in longissimus dorsi adipocytes.Results Porcine SOL-derived exosomes(SOL-EXO) and EDL-derived exosomes(EDL-EXO) were first identified and their average particle sizes were approximately 84 nm with double-membrane disc-shapes as observed via transmission electron microscopy and scanning electron microscopy. Moreover, the intramuscular fat content of the SOL was greater than that of the EDL at 180 days of age, because SOL intramuscular adipocytes had a stronger lipid-accumulating capacity than those of the EDL. Raman spectral analysis revealed that SOL-EXO protein content was much greater than that of EDL-EXO. Proteomic sequencing identified 72 proteins that were significantly differentially expressed between SOL-EXO and EDL-EXO, 31 of which were downregulated and 41 of which were upregulated in SOL-EXO.Conclusions Our findings suggest that muscle-fat tissue interactions occur partly via SOL-EXO promoting adipogenic activity of intramuscular adipocytes.

关 键 词：Adipogenesis Exosome Extensor digitorum longus Intramuscular adipocyte Muscle-fat tissue interaction Pig SOLEUS 

分 类 号：S828[农业科学—畜牧学]