Xu Xiaochun, Zhan Cong, Qiao Jiaqi, Yang Yuxuan, Li Changyuan, Li Pan, Ma Sen
Collaborative Innovation Center for Food Production and Safety, School of Biological Science & Engineering, North Minzu University, Yinchuan 750021, China.
College of Animal Science and Technology, Henan Agricultural University, Zhengzhou 450002, China.
Int J Mol Sci. 2025 Apr 5;26(7):3414. doi: 10.3390/ijms26073414.
Intramuscular fat (IMF) content is a key factor influencing meat properties including tenderness, flavor, and marbling. However, the complex molecular mechanisms regulating IMF deposition, especially the interactions between intramuscular preadipocytes (IMAdCs) and skeletal muscle satellite cells (SMSCs), remain unclear. In this study, a direct co-culture system of sheep IMAdCs and SMSCs was used to elucidate their intercellular interactions. RNA sequencing and bioinformatics analyses were performed under monoculture and co-culture conditions for later stages of differentiation. The obtained results showed that SMSCs significantly inhibited the adipogenic capacity of IMAdCs. This was reflected in the co-culture markedly altered gene expression and observations of lipid droplets in our studies, i.e., the , , , , , , , , , and genes were down-regulated in the co-cultured IMAdCs in association with the inhibition of fat deposition, whereas , , , and within the genes upregulated in co-culture IMAdCs were associated with the promotion of lipid metabolism. In addition, GO, KEGG, and ligand-receptor pairing analyses further elucidated the molecular mechanisms of intercellular communication. These findings emphasize the regulatory role of SMSCs on intramuscular preadipocyte differentiation and lipid metabolism, providing a theoretical framework for targeted molecular strategies to improve sheep meat quality.
肌内脂肪（IMF）含量是影响肉品质的关键因素，包括嫩度、风味和大理石花纹。然而，调节IMF沉积的复杂分子机制，尤其是肌内前体脂肪细胞（IMAdCs）与骨骼肌卫星细胞（SMSCs）之间的相互作用，仍不清楚。在本研究中，采用绵羊IMAdCs和SMSCs的直接共培养系统来阐明它们之间的细胞间相互作用。在分化后期的单培养和共培养条件下进行了RNA测序和生物信息学分析。所得结果表明，SMSCs显著抑制IMAdCs的成脂能力。这在共培养中显著改变的基因表达以及我们研究中对脂滴的观察中得到体现，即在共培养的IMAdCs中， 、 、 、 、 、 、 、 、 和 基因下调，与脂肪沉积的抑制相关，而在共培养的IMAdCs中上调的基因中的 、 、 、 和 与脂质代谢的促进相关。此外，GO、KEGG和配体-受体配对分析进一步阐明了细胞间通讯的分子机制。这些发现强调了SMSCs对肌内前体脂肪细胞分化和脂质代谢的调节作用，为改善绵羊肉品质的靶向分子策略提供了理论框架。
