The certificate published for this listing is Janoshik task 65048, batch SU50968: 2.08 mg reported, 99.357% purity, analysed 15 May 2025. Verification key 5Y6WGJI9VTZ4. That measured amount is what the report says. It is not a certificate for the blend. The product page is TB-500.
TB-500 refers to a specific fragment of thymosin beta-4 (Tβ4), the most abundant intracellular actin-sequestering protein in mammalian cells. The full protein is a 43-amino-acid peptide; TB-500 corresponds to the active domain responsible for actin binding and most of Tβ4's regenerative properties.
Thymosin Beta-4 Biology
Tβ4 is constitutively expressed in virtually all cell types and is released into the extracellular space following tissue injury. Its primary function is sequestering G-actin monomers, regulating the dynamic polymerisation and depolymerisation of the actin cytoskeleton. This regulation is fundamental to cell migration, wound healing, and myogenesis.
Beyond actin dynamics, Tβ4 and its active fragments promote angiogenesis through multiple pathways. Tβ4 upregulates HIF-1α (hypoxia-inducible factor) and VEGF (vascular endothelial growth factor), driving endothelial cell sprouting. It also has direct cardioprotective effects — Tβ4 is one of the few peptides shown to stimulate epicardial progenitor cell migration in adult cardiac tissue.
TB-500 vs Full-Length Tβ4
TB-500 (the Ac-LKKTETQ peptide fragment) retains the actin-binding and angiogenic properties of the full protein while being more amenable to synthesis and formulation. Some studies suggest the fragment may have a more favourable pharmacokinetic profile due to its smaller size, though direct comparative pharmacokinetic studies are limited.
Tissue Repair Evidence
In rodent models of tendon injury, cardiac infarction, corneal damage, and skin wounds, systemic or local Tβ4/TB-500 administration has consistently shown accelerated healing, reduced fibrosis, and improved functional recovery. A corneal wound-healing study in rabbits remains one of the most frequently cited, showing re-epithelialisation 1.7x faster in treated animals.
A small Phase I/II human trial exploring Tβ4 in epidermolysis bullosa showed tolerability and some healing benefit, though the trial was not powered for efficacy conclusions. Tβ4 has also been investigated for cardiac repair post-myocardial infarction, with early human feasibility data suggesting safety.
Systemic vs Local Administration
An important feature of TB-500 research is the apparent systemic distribution of its effects. Unlike some peptides that require local injection at the injury site, Tβ4 fragments have shown regenerative effects on distant tissues when administered systemically in animal models. This suggests a circulating signalling role rather than purely local activity.
Key Points
- Active fragment of thymosin beta-4; retains actin-binding and angiogenic domains
- Promotes VEGF expression and endothelial cell migration
- Strong preclinical evidence across multiple injury models
- Limited but encouraging early human data in epidermolysis bullosa and cardiac repair
- Apparent systemic activity — not limited to local injection site
Research purposes only. Not approved for therapeutic use in humans. All applications require appropriate research authorisation.