147 - The Effects of Creatine Monohydrate and Guanidinoacetic Acid Supplementation on Bovine Satellite Cells

Abstract: Creatine (CRE) is an energy-storing molecule of skeletal muscle and is reported as potential growth promotants. With Guanidinoacetic acid (GAA) being a precursor to creatine, the potential to evaluate supplemental GAA's role in the body from a skeletal muscle focus is needed within the beef industry. Study objectives were to evaluate the effects of CRE and GAA on bovine satellite cells (BSCs) proliferation and myogenic potential. BSCs were obtained from three-month-old Holstein calves (n=3), harvested, and incubated with 10% FBS/DMEM. Following 24h of cell adhesion, BSCs were incubated with treatments: 1) Control, 2) 10mM GAA, and 3) 5mM CRE. Cell proliferation rate was measured at 0, 24, 48, 72, and 96h. In order to identify the effects of CRE and GAA during myogenic differentiation, satellite cells were incubated in a differentiation medium (2% horse serum/DMEM) containing 10mM GAA and 5mM CRE. After 48h, cells were harvested and used for mRNA gene expression (Myh7, MyoG, IGF-1, and S6KB1). One-way ANOVA and Tukey's HSD test were used for gene expression. Two-way ANOVA and Tukey's HSD test were conducted for cell proliferation assay. No interaction effect was noted (P > 0.05) between the effects of treatment against time in end output of cell proliferation. Cell proliferation rate was not altered (P > 0.05), with proliferation rate time measurement having a greater result of cell proliferation (P < 0.001). The expression of IGF-1 was overexpressed (P < 0.05) in GAA treated BSC during the myogenic differentiation. CRE increased (P < 0.01) MyoG expression. GAA and CRE did not alter Myh7 orS6KB1 mRNA gene expression. Results suggest that the treatment of BSCs with creatine or GAA may improve myogenic differentiation and promote skeletal muscle growth via IGF-1, respectively.