Injection of duck recombinant follistatin fusion protein into duck muscle tissues stimulates satellite cell proliferation and muscle fiber hypertrophy

Abstract

Follistatin (FST) can inhibit the expression of myostatin, which is a predominant inhibitor of muscle development. The potential application of myostatin-based technology has been prompted in different ways in agriculture. We previously constructed an expression vector of duck FST and isolated the FST fusion protein. After the protein was purified and refolded, it was added to the medium of duck myoblasts cultured in vitro. The results show that the 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide value of the myoblasts in the duck FST treatment group is higher than that in the control group, which indicates that the duck FST fusion protein exhibits the biological activities that can accelerate myoblast proliferation. To further investigate the roles of duck FST on muscle development, we injected the protein into the duck muscle tissues in vivo. The results show that both the duck muscle fiber cross-sectional area and the satellite cell activation frequency are influenced more in the FST treatment group than they are in the control group. In addition to these phenomena, expression of MyoD and Myf5 were increased, and the expression of myostatin was decreased. Together, these results suggest the potential for using duck FST fusion protein to inhibit myostatin activity and subsequently to enhance muscle growth in vivo. The mechanism by which FST regulates muscle development in the duck is similar to that in mammals and fishes.

Circulating Follistatin Is Liver-Derived and Regulated by the Glucagon-to-Insulin Ratio

“…Importantly, treatment of mice (46) and ducks (47) with repeated injections of recombinant follistatin induces a hypertrophic response in skeletal muscle tissue. In addition, follistatin treatment induces skeletal muscle repair after injury and immobilization (46).…”

Construction of a eukaryotic expression vector for pEGFP-FST and its biological activity in duck myoblasts

“…Previous research has shown that FST is capable of inducing muscle hypertrophy by activating satellite cells and influencing the expression of myogenesis-related genes [13]. Additionally, inhibition of MSTN by FST is a recently identified novel mechanism for the promotion of muscle hypertrophy [8].…”

“…We also cloned the duck FST gene into a prokaryotic expression vector and purified a duck FST recombinant fusion protein. When administered into adult duck leg muscle tissues, the recombinant FST protein was shown to possess biological activity and promote muscle growth [13]. To better understand the mechanism of FST in regulating muscle hypertrophy in birds, we sought to construct a eukaryotic expression vector for duck FST with biological activity in promoting myoblast proliferation and differentiation.…”

Identification of the crucial molecular events during the large-scale myoblast fusion in sheep

“…In mouse and chick, FST functions as a positive regulator of muscle development and growth by inhibiting TGF-␤ family members including myostatin (2,23,34,43,64). As to cellular behavior, FST regulates the proliferation (4,7,23,35), differentiation (4,32), and fusion (29) of muscle cells in myogenesis in vivo and in vitro of mouse and duck. The present evidence (Fig.…”