TB-500 (Thymosin Beta-4): The Good, The Bad & The Research
Explore the science behind TB-500 (Thymosin Beta-4). Research on tissue repair, cardiac benefits, anti-inflammation and more. For Research Use Only.
May 31, 2026 | 10 min read
What Is TB-500?
TB-500 is a synthetic peptide derived from Thymosin Beta-4 (Tβ4), a naturally occurring protein found in virtually every cell of the human body. It is specifically derived from the actin-binding domain of Thymosin Beta-4 — a short sequence responsible for much of its biological activity.
Thymosin Beta-4 was first isolated from thymus tissue and has since been identified as a key regulator of actin — the protein responsible for cell structure, movement, and repair. TB-500 replicates the most active region of this protein, making it a highly targeted research compound.
CAS Number: 77591-33-4
Molecular Formula: C₂₁₂H₃₅₀N₅₆O₇₈S
Molecular Weight: 4963.5 g/mol
⚠️ TB-500 is not FDA approved. All research discussed is preclinical or early clinical. For Research Use Only.
How Does TB-500 Work? (Mechanism of Action)
TB-500’s primary mechanism centers on actin regulation. Actin is one of the most abundant proteins in the body and plays a critical role in cell migration, cell proliferation, and cell differentiation.
By sequestering G-actin (globular actin), TB-500 promotes the dynamic reorganization of the actin cytoskeleton — accelerating the migration of endothelial cells, keratinocytes, and fibroblasts to injury sites.
