The effect of bovine lactoferrin on muscle growth in vivo and in vitro

Lactoferrin was found to be a potent stimulator of proliferation for L6 myoblasts. Both apo and holo-forms of lactoferrin were equipotent. By contrast, only the holo-form of transferrin (a structurally related iron binding protein) stimulated proliferation, apo-transferrin was without activity. Holo-transferrin was also less stimulatory than lactoferrin. Purified lactoferrin was administered to mature female rats and to neonatal rats by daily subcutaneous injection to determine if there was a measurable effect on muscle cell growth in vivo. Results from the in vivo studies suggest that lactoferrin has little or no effect on muscle cell growth in the whole animal.