Investigating Myogenic Potency of Proteolipids Contained Within Fertilized Gallus gallus domesticus Egg Yolk

Abstract Purpose To identify novel fertilized egg yolk–derived compounds that enhance myoblast differentiation, we used a myosin light chain (MLC) luciferase C2C12 reporter cell line to quantify myotube formation, an indicator of myoblast differentiation, in response to adding three different fractions: granule, lipid, and aqueous. Methods A C2C12 MLC-luciferase reporter myoblast cell line was cultured in media supplemented with three different egg yolk–derived fractions. Cellular assays and fluorescence imaging were conducted to determine the viability, morphology, and myotube formation in response to the egg yolk fraction additives. Fertilized and unfertilized egg yolk fractions were examined for their protein MW profile to determine if there were differences in the protein populations. Results None of the fractions had a negative effect on cellular viability measured on days 0, 3, 7, and 10. Two fractions showed increased differentiation compared to the null control (1%): the granule and the lipid. Comparison of the MW profiles of the fractions confirmed differences in protein populations between them with apo-LDLs, apo-HDLs, and phosvitin being the major bands present in the granule and lipid groups. No differences in protein profiles were observed between the fertilized and unfertilized groups. Conclusion Granule- and lipid-fertilized egg yolk–derived fractions show potential for use as differentiating agents for myotube formation in C2C12 myoblasts supporting their nutritional value for treatment of sarcopenia or to enhance myoblast differentiation for tissue engineering. Lay Summary Sarcopenia or muscle wasting is a prevalent problem in the elderly population which leads to increased healthcare costs. We have separated fertilized egg yolk into fractions to test their potential to increase muscle formation by adding them to muscle progenitor cells. Some of these fractions show great potential for increase differentiation of muscle tissue in treatment of sarcopenia or for muscle tissue engineering.