Follistatin (FST344) — Activin-Binding Protein

Pharmaceutical Form: Peptide for reconstitution | Alias: Activin-Binding Protein

Presentation

Each 2ml multi-dose vial contains 2mg/vial, with Keifei® wording imprinted on the side. Vials feature a purple flip-off cap stamped with Keifei®. Supplied as:

• 3 × 2mg vials + 3 × 2ml bacteriostatic water ampoules inside a white & purple box with plastic insert.
• One set of 10-digit authentication codes affixed to the plastic tray.

About Follistatin

Follistatin (FST344), also called Activin-Binding Protein, is a secreted glycoprotein expressed in nearly all tissues of higher animals. It contains 3 follistatin-like domains, 3 Kazal-like domains, and 1 TGF-β binding (TB) domain. It is primarily produced by folliculostellate (FS) cells of the anterior pituitary.

Mechanism of Action

• Inhibition of FSH: Follistatin is a specific inhibitor of the biosynthesis and secretion of pituitary follicle-stimulating hormone (FSH).
• Activin antagonist: It binds directly to activin, blocking its signaling pathways.
• Isoforms: Isoform 1 is the predominant form in serum but absent in follicular fluid.

Physiological Role

Initially identified as FSH-suppressing protein (FSP), follistatin was isolated from follicular fluid due to its ability to inhibit FSH secretion. Together with BMPs, it plays a key role in ovarian folliculogenesis.

• Promotes progression of the follicle from early antral to antral/dominant stages.
• Encourages differentiation of granulosa cells (GC) into estrogen-producing cells.
• Supports transition of GC into progesterone-producing luteal cells of the corpus luteum.

Key Points

• Potent regulator of FSH secretion.
• Functions as an activin antagonist.
• Critical role in folliculogenesis and ovarian function.
• Expressed across a wide range of tissues.
• Supplied with QR authentication to ensure originality.

Important: Follistatin is a research peptide. Handling and use should be restricted to professionals in compliance with local regulations.