What Is TB-500?
TB-500 is a synthetic peptide corresponding to the amino acid sequence 17–23 of Thymosin Beta-4 (Tβ4), a naturally occurring 43-amino-acid peptide found abundantly in nearly every cell in the human body. Tβ4 is particularly concentrated in platelets and wound fluid, suggesting a significant physiological role in repair processes.
The active fragment — sometimes described as the "actin-binding domain" — is the basis of TB-500. Research interest in this synthetic version centers on whether it can recapitulate the full biological activity of native Tβ4.
Mechanism of Action
Actin Sequestration
The primary and best-characterized mechanism of Tβ4 (and by extension TB-500) is G-actin sequestration. The peptide binds to monomeric (G) actin, preventing its polymerization into filamentous (F) actin. This regulation of actin dynamics is fundamental to cell migration — particularly critical during wound healing when cells must migrate to close tissue defects.
Angiogenesis and Tissue Remodeling
Multiple preclinical studies document Tβ4's ability to promote angiogenesis. The peptide upregulates plasminogen activator and matrix metalloproteinases (MMPs), enzymes necessary for extracellular matrix remodeling and new vessel formation. This has made TB-500 of substantial interest in cardiovascular and musculoskeletal repair research.
Anti-Inflammatory Effects
Tβ4 has been shown in several models to downregulate NF-κB — a central transcription factor in inflammatory cascades — and to reduce levels of pro-inflammatory cytokines including TNF-alpha and IL-1beta.
Key Research Areas
| Area | Model | Observation |
|---|---|---|
| Cardiac Repair | Mouse / Rat | Improved cardiomyocyte survival post-infarction |
| Corneal Healing | Rat | Accelerated epithelial wound closure |
| Tendon/Ligament | Rat | Improved mechanical strength recovery |
| Dermal Wound | Rat | Faster wound closure, improved collagen deposition |
| Neurological | Mouse | Increased oligodendrocyte differentiation |
"Thymosin beta-4 promotes angiogenesis, wound healing, and hair follicle development — activities consistent with G-actin regulation and downstream MMP modulation." — Preclinical literature summary.
Purity & Verification
Reconstitution & Storage
TB-500 is supplied as a lyophilized powder. Reconstitute with bacteriostatic water using the same approach as other lyophilized peptides — inject BAC water slowly along the vial wall, swirl gently, do not shake. Store reconstituted solution at 2–8°C for up to 30 days. Keep lyophilized powder at −20°C.
| Form | Storage | Shelf Life |
|---|---|---|
| Lyophilized (unopened) | −20°C | 24+ months |
| Reconstituted | 2–8°C | 30 days |
For research use only. Not for human or animal use. Order TB-500 here.