State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock, College of Life Science, Inner Mongolia University, Hohhot, 010070, China.
Commun Biol. 2024 Nov 26;7(1):1575. doi: 10.1038/s42003-024-07252-9.
Myostatin (MSTN) is a negative regulator of muscle growth, and its relationship with the gut microbiota is not well understood. In this study, we observed increase muscle area and branched-chain amino acids (BCAAs), an energy source of muscle, in myostatin knockout (MSTN-KO) cattle. To explore the link between increased BCAAs and rumen microbiota, we performed metagenomic sequencing, metabolome analysis of rumen fluid, and muscle transcriptomics. MSTN-KO cattle showed a significant increase in the phylum Bacteroidota (formerly Bacteroidetes), particularly the genus Prevotella (P = 3.12e-04). Within this genus, Prevotella_sp._CAG:732, Prevotella_sp._MSX73, and Prevotella_sp._MA2016 showed significant upregulation of genes related to BCAA synthesis. Functional enrichment analysis indicated enrichment of BCAA synthesis-related pathways in both rumen metagenomes and metabolomes. Additionally, muscle transcriptomics indicated enrichment in muscle fiber and amino acid metabolism, with upregulation of solute carrier family genes, enhancing BCAA transport. These findings suggest that elevated rumen Prevotella in MSTN-KO cattle, combined with MSTN deletion, synergistically improves muscle growth through enhanced BCAA synthesis and transport.
肌肉生长抑制素 (MSTN) 是肌肉生长的负调控因子，但其与肠道微生物群的关系尚不清楚。在本研究中，我们观察到肌肉生长抑制素敲除 (MSTN-KO) 牛的肌肉面积和支链氨基酸 (BCAA) 增加，BCAA 是肌肉的能量来源。为了探索增加的 BCAA 与瘤胃微生物群之间的联系，我们进行了宏基因组测序、瘤胃液代谢组分析和肌肉转录组学分析。MSTN-KO 牛的厚壁菌门（原拟杆菌门）显著增加，特别是普雷沃氏菌属（P = 3.12e-04）。在这个属中，Prevotella_sp._CAG:732、Prevotella_sp._MSX73 和 Prevotella_sp._MA2016 与 BCAA 合成相关的基因显著上调。功能富集分析表明，瘤胃宏基因组和代谢组中都存在 BCAA 合成相关途径的富集。此外，肌肉转录组学表明肌肉纤维和氨基酸代谢富集，溶质载体家族基因上调，增强了 BCAA 的转运。这些发现表明，MSTN-KO 牛中升高的瘤胃普雷沃氏菌与 MSTN 缺失协同作用，通过增强 BCAA 的合成和转运来促进肌肉生长。
