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

Abstract

Emerging research suggests that hormones found in anabolic implants interact with polyamine biosynthesis. The objective of this study was to determine the effects of steroidal hormones, polyamines and polyamine precursors on bovine satellite cell (BSC) differentiation and polyamine biosynthesis temporally. Primary BSCs were induced to differentiate in 3% horse serum (CON) and treated with 10 nM trenbolone acetate (TBA), 10 nM estradiol (E2), 10 nM TBA and 10 nM E2, 10 mM methionine, 8 mM ornithine, 2 mM putrescine, 1.5 mM spermidine, or 0.5 mM spermine. Total mRNA was isolated 0, 2, 4, 8, 12, 24, and 48 h post-treatment. Abundance of mRNA for genes associated with induction of BSC differentiation: paired box transcription factor 7, myogenic factor 5, and myogenic differentiation factor 1 and genes in the polyamine biosynthesis pathway: ornithine decarboxylase and S-adenosylmethionine—were analyzed. Overall, steroidal hormones did not impact (p > 0.05) mRNA abundance of genes involved in BSC differentiation, but did alter (p = 0.04) abundance of genes involved in polyamine biosynthesis. Polyamine precursors influenced (p < 0.05) mRNA of genes involved in BSC differentiation. These results indicate that polyamine precursors and polyamines impact BSC differentiation and abundance of mRNA involved in polyamine biosynthesis, while steroidal hormones altered the mRNA involved in polyamine biosynthesis.

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

“…Implants have the added benefit of also increasing both the environmental sustainability of the industry [2] and economic return to producers [15]. However, despite the clear benefits of implanting, the exact physiological and molecular mechanism that anabolic implants operate through to increase overall growth and efficiency remains elusive [9,12]. Furthermore, when trace minerals are supplemented at higher concentrations recommended by feedlot consultants, rather than national research council recommendations, an increase in growth is observed [13].…”

“…Anabolic implants increase economically viable traits such as average daily gain (ADG), feed intake, feed efficiency (FE), hot carcass weight (HCW), and ribeye area (REA) [4,7]. However, the exact physiological and molecular mechanisms by which anabolic implants operate to increase skeletal muscle growth in cattle remains elusive [9][10][11][12]. Furthermore, the increase in growth caused by anabolic implants, may increase trace mineral requirements to support skeletal muscle growth [13], as lambs implanted with zeranol tended to retain greater amounts of Zn, and lose less Cu and Mn in feces and urine [14].…”

Understanding the Effects of Trenbolone Acetate, Polyamine Precursors, and Polyamines on Proliferation, Protein Synthesis Rates, and the Abundance of Genes Involved in Myoblast Growth, Polyamine Biosynthesis, and Protein Synthesis in Murine Myoblasts

“…Control cultures received just SFM. The treatment concentrations used in the analysis of protein synthesis were selected based upon results from past studies completed by our laboratory that impacted the growth of bovine satellite cells [ 22 , 31 ]. Additionally, in the protein synthesis study, which was completed after the proliferation study, the E2 and TBA + E2 treatments were added because further review of past literature demonstrated evidence for a potential interaction between E2 and polyamine biosynthesis [ 29 , 30 ].…”

“…Briefly, cell lysate was collected at three different time points for analysis relative to proliferation (0.5, 12 and 24 h post-treatment) or protein synthesis (1, 12, and 24 h post-treatment). These time points were based off of previous work completed by our research group that demonstrated changes in gene expression in bovine satellite cells [ 22 , 31 ]. In addition, these specific time points were chosen because changes in gene expression are likely to be observed prior to a gross change in proliferation or protein synthesis.…”

“…However, the exact mechanism through which androgens increase growth of skeletal muscle is unknown. Past research suggests that one mechanism by which androgens, such as trenbolone acetate, and estrogens, such as estradiol-17β (E2), may improve growth is through an interaction with the polyamine biosynthetic pathway [ 22 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 ].…”