Increasing levels of sodium benzoate affect myosin heavy chain type expression in cultured bovine satellite cells

Abstract Text:

Sodium benzoate is used by commercial bakers to increase tolerance in yeast to calcium propionate, a mold inhibitor.  Yeast cell wall is produced during the production of yeast extract from primary grown bakers yeast.  While this primary grown yeast is washed before yeast cell wall is produced from the culture, some residual sodium benzoate may be retained.  Due to increasing interest in feeding yeast cell wall to feedlot cattle, the present study was conducted to examine the effects of sodium benzoate on bovine muscle satellite cells (BSC).  Cultured BSC were grown to confluence and treated with increasing levels of sodium benzoate added to the differentiation media, a negative control, 0.001 μM, 0.01 μM, 0.1 μM, 1 μM, 10 μM, and 100 μM, with 4 wells per dose.  The cells were allowed to differentiate for 48 hours and then harvested for RNA and protein analysis.  The 1 μM dose increased (P < 0.05) the gene expression of AMPKα compared with the 0.001 μM dose and tended (P < 0.10) to be greater than the 0.01 μM dose.  The 0.1 μM dose tended (P < 0.10) to have a greater expression of the AMPKα gene compared with the 0.001 μM dose.  Concentrations IGF-1 mRNA were greater in the 0.1 μM dose compared with the control (P < 0.05).  Among the cultures receiving sodium benzoate, there was a numerical increase of myosin heavy chain (MHC) type I gene expression as concentration of sodium benzoate increased, with the 10 μM and 100 μM doses having greater (P < 0.05) gene expression than the control, 0.001 μM, and 0.01 μM doses.  The 0.001 μM dose tended (P <0.10) to have a lower abundance of MHC type I mRNA than the 0.1 μM and 1 μM doses.  The 100 μM dose had a greater expression of MHC type IIA than the control, 0.001 μM, and 0.01 μM doses (P < 0.05).  The 10 μM and 100 μM doses had greater (P < 0.05) levels of MHC type IIX mRNA compared with the control, 0.001 μM, and 0.01 μM doses.  The 0.01 μM dose had a greater (P < 0.05) concentration of AMPKα protein than the 10 μM and 100 μM doses.  These results indicated sodium benzoate could induce MHC type I expression in cultured BSC.

Keywords: benzoate, myosin, satellite cells