
Originally Posted by
MuscleScience
Muscle cells are terminally differentiated cells. They under virtually no circumstance de-differentiate (anaplasia) back to a more primordial cell type and undergo mitosis. Hyperplasia and Metaplasia are often times mistaken as the same thing. Metaplasia adds to the nuclear count of a muscle fiber, but is a one for one addition. Satellite cells are progenitor cells that when called upon first differentiate into a myoblastic cell before final terminal differentiation. This is a one for one process. To date in the literature Metaplasia is not considered a major contributor to muscle growth. Hyperplasia if it does occur in humans (cant say with certainty that it doesnt) should and could be very easily identified with simple muscle biopsy and nuclear staining techniques, when the process of mitosis initiates.
It is true that in some research it has shown that with certain cocktails of growth factors and or viral exposure that some anaplastic effect can be demonstrated in vitro. However this process has not been seen in vivo. Additionally under viral exposure and cancerous conditions, in vivo muscle cells can again be forced back into state of mitotic reproduction. This is of course different and is termed neoplasia or sometimes called desmoplasia because it does not form normal myogenic tissue.