Butyrate Influences Myogenic Potential of Porcine Satellite Cells

Dietary butyrate supplementation has been shown to increase growth performance in weaned pigs, which has been attributed to its beneficial effects on intestinal health. Butyrate ability to trigger cellular differentiation has been reported in several different human malignancies both in vitro and in vivo. Its effect on satellite cell activity remains controversial, as previous studies have reported that butyrate can either increase or decrease satellite cell differentiation into myoblasts. Recent muscle injury model studies suggest that butyrate speeds muscle repair and growth. Our objective was to determine the effect of butyrate on the proliferation and differentiation potential of porcine satellite cells in vitro. Primary satellite cells were isolated from newly weaned pigs (n = 6, 21±2 days old) and cultured in media designed to promote proliferation (10% FBS + DMEM) or differentiation (2% horse serum + DMEM). Media was supplemented with either 0, 0.1, 0.5, or 1mM of sodium butyrate (NaBu). Under proliferative conditions, proliferation rates were reduced at the highest concentration of (NaBu) after 24h. After 48h there was a dose‐dependent reduction in proliferation rate based on NaBu concentration. There was no increase in the rate of apoptosis, as assessed by TUNEL staining. Under proliferative culture conditions, there were no significant changes in the gene expression of Pax7, or of two muscle regulatory factors (MRFs), MyoD and MyoG. Under culture conditions designed to promote differentiation, the presence of NaBu allowed for greater gene expression of MyoD and MyoG, without an increase in Pax7 gene expression. Butyrate is an inhibitor of histone deacetylases, and it may be via this mechanism that it upregulates these MRFs in satellite cells. Altering satellite cell myogenic potential in vivo could dramatically effect growth performance in pigs.