Meeting Abstract
Myoglobin is a hemoprotein that is involved in oxygen storage and transport, a nitric oxide and reactive oxygen species scavenger, and has shown interactions suggesting a role in cellular lipid transport. Typically, myoglobin expression follows an established slow muscle fiber type. These slow muscle fibers contain a protein called myosin heavy chain I and are found in endurance muscles. Interestingly, recent evidence has shown a change in myoglobin expression without a change in fiber type. This indicates that myoglobin expression is not always fiber type dependent and could be expressed through alternate mechanisms. Our lab has shown that mixed lipid supplements elevate myoglobin levels in cells from terrestrial and marine mammals, but it is unknown how these supplements affect myoglobin expression relative to the fiber type of the cultured tissue. To investigate, we have cultured and differentiated C2C12 myoblasts in the presence and absence of lipid. Cells were then harvested each day after differentiation initiation. Western blots were conducted to ascertain the expression of myoglobin and myosin heavy chain I and assayed for functional myoglobin content. With these methods, we have found myoglobin expression prior to that of myosin heavy chain I. This could indicate that there are pathways to myoglobin expression independent from fiber type expression. Examination of alternate routes of myoglobin expression that are not reliant on fiber type establishment could yield potential therapeutic benefits to combat ischemic diseases seen in humans.
