Follistatin 344 1mg (FST)
 
Overview
Follistatin (FST) is a secreted glycoprotein that plays a critical role in regulating various biological processes. Initially discovered as a follicle-stimulating hormone (FSH) inhibiting substance in ovarian follicular fluid, Follistatin is a key modulator of the TGF-beta (Transforming Growth Factor Beta) family of ligands. Human Follistatin, encoded by a cDNA sequence, consists of 344 amino acids and includes multiple functional domains, such as an atypical TGF-beta binding domain and three Follistatin domains that feature EGF-like and Kazal-like motifs. The protein binds and inhibits a wide range of TGF-beta ligands, modulating their activity and blocking their access to signaling receptors. Notably, Follistatin antagonizes proteins like Myostatin, GDF-11, BMPs (bone morphogenetic proteins), and TGF-Beta1, which are involved in regulating growth, muscle development, and other crucial physiological functions.
Mechanism of Action
Follistatin exerts its effects by binding directly to ligands of the TGF-beta family, preventing their interaction with activin receptors and other cell surface receptors. This inhibition significantly influences various cellular functions, including growth, differentiation, and regeneration. Follistatin’s role in regulating myogenesis (muscle development) through the inhibition of Myostatin and GDF-11 is of particular interest, as these proteins typically act to limit muscle growth and regeneration. By counteracting their effects, Follistatin has been studied for its potential to promote muscle hypertrophy and tissue regeneration.
Clinical Applications and Benefits
Muscle Growth and Regeneration
Follistatin is well known for its ability to inhibit Myostatin, a negative regulator of muscle growth. Myostatin inhibits muscle differentiation and hypertrophy, and its suppression by Follistatin has shown promising results in promoting muscle growth, improving muscle mass, and aiding in muscle regeneration. Clinical studies have indicated that Follistatin-based therapies could be beneficial in treating muscular dystrophies or age-related muscle wasting (sarcopenia) (Ref: Amthor, et al., 2009).
Treatment of Muscle Wasting Disorders
Follistatin has garnered significant attention in the treatment of muscle wasting disorders, such as cachexia (a severe weight loss condition often associated with cancer or chronic diseases). By inhibiting Myostatin and GDF-11, Follistatin can counteract the muscle atrophy seen in these conditions. Studies in animal models have shown that Follistatin promotes muscle preservation and improves muscle function in conditions of chronic muscle wasting (Ref: Ríos, et al., 2015).
Reproductive Health and Fertility
Follistatin's role in regulating FSH levels is critical in reproductive health. By inhibiting Activin A, Follistatin can suppress the expression and secretion of FSH from the pituitary gland, which plays a key role in the development of ovarian follicles in women and spermatogenesis in men. This has led to investigations into Follistatin's potential in fertility treatments, particularly for ovarian dysfunction or FSH-related infertility (Ref: Ueno, et al., 2010).
Anti-Aging and Tissue Regeneration
Beyond its effects on muscle, Follistatin has also been explored for its role in tissue regeneration and anti-aging therapies. The inhibition of Myostatin and GDF-11—proteins that increase with age and limit muscle and tissue regeneration—has led to the hypothesis that Follistatin may help delay aging-related decline in muscle function, tissue repair, and overall vitality (Ref: Sinha, et al., 2014).
Bone Health
Follistatin is also involved in regulating bone morphogenetic proteins (BMPs), which play a pivotal role in bone formation and repair. By modulating BMP signaling, Follistatin has the potential to promote bone regeneration and improve bone density, which is especially relevant in conditions like osteoporosis or following fractures (Ref: Tuckermann, et al., 2001).
Safety and Efficacy
Follistatin has been shown to have a favorable safety profile in clinical studies, with most adverse effects being minor and related to dosing regimens. As a peptide, it is typically administered under medical supervision to ensure precise regulation of its effects on muscle growth and other physiological systems. Careful monitoring is required to avoid overstimulation of tissue growth and other unintended effects.
References:
Amthor, H., et al. (2009). Inhibition of myostatin and GDF-11 by follistatin enhances muscle growth and regeneration. Proceedings of the National Academy of Sciences USA.
Ríos, J. L., et al. (2015). Follistatin as a potential therapeutic target in muscle wasting diseases. Journal of Clinical Investigation.
Ueno, N., et al. (2010). The role of follistatin in fertility and reproductive health. Human Reproduction Update.
Sinha, M., et al. (2014). Myostatin inhibition and the potential of Follistatin in anti-aging therapies. Aging Cell.
Tuckermann, J. P., et al. (2001). Follistatin regulation of BMPs and implications for bone health. Journal of Bone and Mineral Research.