Satellite cells and their regulation in livestock

Abstract

Satellite cells are the myogenic stem and progenitor population found in skeletal muscle. These cells typically reside in a quiescent state until called upon to support repair, regeneration, or muscle growth. The activities of satellite cells are orchestrated by systemic hormones, autocrine and paracrine growth factors, and the composition of the basal lamina of the muscle fiber. Several key intracellular signaling events are initiated in response to changes in the local environment causing exit from quiescence, proliferation, and differentiation. Signals emanating from Notch, wingless-type mouse mammary tumor virus integration site family members, and transforming growth factor-β proteins mediate the reversible exit from growth 0 phase while those initiated by members of the fibroblast growth factor and insulin-like growth factor families direct proliferation and differentiation. Many of these pathways impinge upon the myogenic regulatory factors (MRF), myogenic factor 5, myogenic differentiation factor D, myogenin and MRF4, and the lineage determinate, Paired box 7, to alter transcription and subsequent satellite cell decisions. In the recent past, insight into mouse transgenic models has led to a firm understanding of regulatory events that control satellite cell metabolism and myogenesis. Many of these niche-regulated functions offer subtle differences from their counterparts in livestock pointing to the existence of species-specific controls. The purpose of this review is to examine the mechanisms that mediate large animal satellite cell activity and their relationship to those present in rodents.

Supplementing organic-complexed or inorganic Co, Cu, Mn, and Zn to beef cows during gestation: postweaning responses of offspring reared as replacement heifers or feeder cattle

“…The intramuscular region, however, is the last depot for adipogenesis in growing cattle (Oliveira et al, 2011), and the puberty process is likely more influenced by subcutaneous fat accretion ( Lammoglia et al, 2000 ; Garcia et al, 2002 ; Roberts et al, 2017 ). In turn, myogenic factors are downregulated as cattle mature and muscle fibers are fully developed ( Picard et al, 2002 ; Du et al, 2010 ); hence, treatment differences noted for mRNA expression of myogenin and PAX7 in the LM (day 584) may be indicative of hastened physiological maturation in heifers from AAC cows ( Gonzalez et al, 2020 ).…”

The Impact of Polyamine Precursors, Polyamines, and Steroid Hormones on Temporal Messenger RNA Abundance in Bovine Satellite Cells Induced to Differentiate

“…In the current study, when the BSCs were induced to differentiate, PAX7 mRNA abundance increased 2 h post-induction, and then proceeded to decrease in abundance. One possible explanation for this is that satellite cells are a heterogeneous population, with a portion of cells remaining in reserve and proliferating, not differentiating [ 8 ]. Additionally, the compounds used in this study have been found to increase proliferation rates of BSCs [ 25 ], and therefore it would not be surprising if some of the cells remained in a proliferative phase initially when being induced to differentiation.…”

“…Satellite cells are muscle precursor cells that proliferate, then differentiate and fuse into myotubes or with existing muscle fibers to support hypertrophy [ 5 ]. Differentiation and phenotypic maturation are necessary for satellite cells to fuse [ 8 ]. Markers of differentiation in skeletal muscle include increased expression of myogenic differentiation factor 1 (MyoD ), myogenic factor 5 ( Myf5 ), and myogenin, and decreased expression of paired box transcription factor 7 ( Pax7 ) [ 6 , 9 , 10 ].…”

Anabolic Implants Varying in Hormone Type and Concentration Influence Performance, Feeding Behavior, Carcass Characteristics, Plasma Trace Mineral Concentrations, and Liver Trace Mineral Concentrations of Angus Sired Steers

“…Zinc is vital to cellular proliferation [26] and is a cofactor to metalloproteinases 2 and 9 [27], both of which are associated with increased proliferation rates [11], and protein turnover [10] in bovine satellite cells. Satellite cells are essentially muscle precursor cells [28] and are required to support skeletal muscle hypertrophy. Increasing satellite cell numbers allows for an increased capacity for skeletal muscle growth to occur [29].…”