Follistatin 315

Follistatin, also called activin-binding protein, is found in nearly all tissues of vertebrate animals. Its primary function is to neutralize members of the TGF-β family, which play fundamental roles in everything from growth and development to energy homeostasis and immune system regulation. In particular, follistatin interacts with activin, which plays an important part in cell proliferation and cell death as well as in the immune response as it applies to wound repair.

Follistatin 344 and 315 are engineered analogues of naturally occurring follistatin. Both are created by alternative splicing of the follistatin mRNA transcript. Scientific research in non-human primates as well as in mice have indicated that both molecules are capable of improving muscle growth by antagonizing myostatin (a member of the TGF-β family).

Follistatin is fascinating protein that can increase muscle mass beyond natural potential by suppressing myostatin. Scientists first identified follistatin while examining porcine (re: pig) follicular fluid in the ovaries.

Follistatin is naturally found in the skeletal muscle of almost all mammals with advanced or developed characteristics, such as humans, rodents, and cows. Follistatin is high in the non-essential amino acid cystine but unlike most proteins discussed in the fitness world, follistatin has carbohydrates attached to it.