What is Follistatin-315?

Follistatin-315 is one of three isoforms of naturally occurring Follistatin. This glycoprotein is produced predominantly in the liver but can be found in almost all body tissues. According to research, Follistatin-315 accounts for 95% of all FSTs in the body. [R]

In animal studies, FST-315 has demonstrated some peculiar effects. For instance, this FST appears to be predominantly localized in circulation. It also demonstrates a low binding affinity for heparin, a compound that inhibits blood coagulation in the body. [R]

FST-315 also exhibits excellent and irreversible binding affinity to activins, a protein complex that has a variety of effects in different tissues. For instance, activins increase scar formation in some tissues and inhibit it in others. FST-315 opposes these effects. [R]

FST-315 has exhibited excellent subcutaneous bioavailability and a tolerable safety profile in mice. These effects have not been investigated in humans. Clinical research is thus needed to fully substantiate the effects of FST-315 in randomized populations.

How Does Follistatin-315 Work?

These are the proven effects of FST-315 :

• Inhibits the action of activins. Activins are protein complexes that are involved in apoptosis (cell death), fibrosis inflammation, and cancer development. As an inhibitor of activins, FST opposes all these effects. [R][R]
• Blocks the activity of myostatin. Myostatin is a hormone produced by muscle cells. Ironically, it inhibits the growth and differentiation of muscle mass. Myostatin opposes muscle growth to facilitate easy muscle movement. [R][R]
• Impedes the action of GDF-11. Growth differentiation factor 11 is a protein with essential functions in the heart, skeletal muscle, and brain. It is primarily expressed in the nervous system, limbs, and spinal cord. [R]
• Inhibits the activity of the follicle-stimulating hormone. Follicle-stimulating hormone is involved in the production of sperm (spermatogenesis). It also helps control the menstrual cycle and stimulates the growth of eggs in the ovaries. [R][R]

Follistatin-315 vs Follistatin-344

Follistatin 315 and Follistatin 344 are two isoforms of the protein follistatin, which is naturally produced in the body. Although they have similarities, there are distinct differences between the two isoforms.

Follistatin 315 is the shorter isoform of follistatin, consisting of 315 amino acids. It is primarily known for its role in binding and inhibiting the action of myostatin, a protein that regulates muscle growth and limits muscle mass. By blocking myostatin, follistatin 315 can potentially promote muscle growth and hypertrophy. It is believed to have potent anabolic effects.

Follistatin 344 is the longer isoform of follistatin, consisting of 344 amino acids. Like follistatin 315, it also acts as a myostatin inhibitor and promotes muscle growth. However, follistatin 344 has an additional peptide sequence at its C-terminus, which may provide further research benefits. This additional peptide sequence is thought to help increase its stability and enhance its interaction with cell surfaces.

Follistatin-315 Research

Following is a summary of existing research on FST-315. The information presented in this section is for educational purposes only and doesn’t constitute medical advice. PureRawz doesn’t sell Follistatin-315 for human consumption.

Follistatin-315 and Muscle Growth

Early research on this activin-binding protein led to the production of the ‘mighty’ mouse, whose weight was 4x as much as that of the average mouse. Subsequent research indicated that FST-315 knocked out the myostatin gene to give the mice twice the muscle mass of controls. [R][R]

Further research showed that the increase in muscle wasn’t solely due to the inhibition in the activity of the myostatin gene. Other regulators of muscle mass with similar activity to myostatin were also responsible. To date, those other regulators are yet to be determined. [R]

Follistatin-315 and Muscle Strength

According to a preclinical study involving nonhuman primates, the FST gene enhances muscle growth as well as strength in nonhuman primates. These effects were observed by the administration of Follistatin 344, from which FST-315 is produced by alternative splicing. [R][R]

In another study, researchers injected normal and dystrophic mice with the human FS344 transgene, which encodes the FS-315 protein isoform. This treatment led to significant increases in muscle mass and strength even when given to older mice. [R]

Follistatin-315 and Hair Growth

In a clinical trial involving 26 men with male-pattern baldness, a single injection of follistatin and other growth factors increased hair density. An increase in hair shaft thickness, terminal hair density, and thickness density was also observed at the treated site. [R]

Given that FST-315 is the most predominant form of FST in the bloodstream, the above effect can be attributed to it. Still, more hair research is needed.

Follistatin-315 and Fertility

In a mouse model, female mice treated with FST-315 displayed a short period of neonatal growth retardation and female infertility.

The latter may be due to a decline in the ovarian follicular population. Plus, mice treated with this bone morphogenic protein had improved survival compared to members of the control group. [R]

Frequently Asked Questions

What is Follistatin?

Follistatin is a single-chain glycoprotein. It is produced predominantly in the liver but can be found in almost all tissues. In clinical studies, this protein has demonstrated the ability to increase muscle mass, improve hair density, and prevent muscle dysfunction. [R][R][R]

What is the half-life of follistatin?

Follistatin (molecular weight 31.5 kDa) has a relatively short half-life of 90 – 122 minutes.

Can follistatin prevent muscular dystrophy?

It is delivered by adeno-associated virus (AAV) and has been shown to increase the size and function of muscle in patients with neuromuscular disease. [R]

Can follistatin prevent breast cancer?

In a mouse model of HER-2-positive breast cancer, follistatin was reported to be a metastasis suppressor. Experimental data revealed reduced FST expression in breast cancers compared with normal tissue. [R]

Where to Buy Follistatin Online?

PureRawz is the best place to buy the highest-quality FST-315 online.

In order to be the best supplier of research chemicals, we provide reference materials with every product we sell. All of our products come with an independent, third-party-issued Certificate of Analysis for identification, purity, and concentration.

We offer free international shipping on all orders above $100. You can pay for your purchase through various methods, including PayPal and Bitcoin. We sell liquid, powder, and capsule high-quality TUDA formulations. All the formulations are equally high-quality.

Summary

FST-315 is a synthetic analog of the naturally occurring protein. Preclinical studies have shown that it inhibits the action of myostatin, the hormone that impedes muscle growth. PureRawz sells Follistatin-315 for laboratory and research purposes only.