The objective of the study was to evaluate the effects of chromium (Cr) and methionine on myogenic gene expression, GLUT4 and insulin receptor (IR) synthesis, and amino acid uptake in differentiated bovine satellite cells. Cells were treated with 0, 1, or 10 μM of chromium acetate (CrAc) and 0, 1, or 10 mg/mL of methionine, with cells utilized for the amino acid assay receiving 0.1 μM instead of 1 μM of CrAc. The addition of 10 μM of Cr tended to downregulate AMPKα mRNA gene expression (P < 0.1). Myogenin was impacted by methionine and CrAc with high doses and low doses upregulating expression (P < 0.01). The ratio and protein levels of AMPKα to pAMPKα, GLUT4, and IR abundance were not affected (P > 0.1). Increase in time decreased concentrations of leucine, isoleucine, threonine, methionine, phenylalanine, glutamine, ornithine, lysine, and cysteine (P < 0.01) in conditioned media. Over time, alanine increased (P < 0.01). Methionine inclusion increased alanine, proline, glutamic acid, ornithine, and tryptophan concentrations, as well as decreased leucine, isoleucine, and cysteine (P < 0.01). CrAc only affected glutamine and tryptophan, which both increased with CrAc dose, whereas alanine decreased (P < 0.01). Methionine decreased over time within the 10 mg/mL group (P < 0.01). Tryptophan was generally unaffected but decreased in the 0 mg/mL group at 48 h. Cysteine decreased with a decreased dosage of CrAc at 24 h (P < 0.01). Lysine was generally unaffected by this interaction (P > 0.1), with the exception of the 0.1 μM treatment group at 24 h being higher (P < 0.01). CrAc affected the uptake of alanine, glutamine, and tryptophan (P < 0.01). Methionine inclusion increased alanine, proline, glutamic acid, ornithine, and tryptophan, as well as decreased leucine, isoleucine, and cystine (P < 0.01). Increased time saw a significant decrease in leucine, isoleucine, threonine, methionine, phenylalanine, glutamine, ornithine, lysine, and cystine (P < 0.01) and an increase in alanine (P < 0.01).
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