TB-500

TB-500 is a synthetic peptide based on the active region of Thymosin Beta-4 (TB4), a naturally occurring 43-amino acid peptide found in virtually all human and animal cells. Thymosin Beta-4 is one of the most abundant intracellular peptides and plays a fundamental role in cell motility, wound healing, and tissue repair.

Originally identified in the thymus gland (hence the name), Thymosin Beta-4 has since been found to be expressed in nearly every tissue type. Its primary intracellular function is sequestering G-actin (monomeric actin), which regulates the polymerization of actin into filaments — the structural scaffolding that cells use for movement and shape maintenance.

TB-500 gained widespread attention in equine medicine, where it has been used to treat injuries in racehorses. Its use in human research and the biohacking community has grown significantly, particularly in combination with BPC-157 (the "Wolverine Stack") for accelerated injury recovery.

TB-500 exerts its healing effects through several key mechanisms:

Actin regulation and cell migration: By binding to and sequestering G-actin, TB-500 promotes the formation of new actin filaments. This is crucial because actin dynamics drive cell migration — the process by which cells move toward injury sites to begin repair. Enhanced cell migration means faster recruitment of repair cells to damaged tissues.

Angiogenesis: TB-500 promotes the formation of new blood vessels, ensuring that healing tissues receive adequate oxygen and nutrient supply. This is particularly important for injuries in areas with poor blood supply, such as tendons and ligaments.

Anti-inflammatory effects: TB-500 has been shown to downregulate inflammatory cytokines and reduce inflammation at injury sites, creating a more favorable environment for tissue repair.

Stem cell differentiation: Research suggests TB-500 may promote the differentiation of stem cells into specific tissue types needed for repair, potentially enhancing the quality of healed tissue.

Keratinocyte and endothelial cell migration: TB-500 specifically promotes the migration of keratinocytes (skin cells) and endothelial cells (blood vessel lining cells), explaining its wound healing and angiogenic properties.

Wound healing: Multiple animal studies demonstrate accelerated wound closure with Thymosin Beta-4 treatment. Topical application in rat models showed faster wound contraction and re-epithelialization (Malinda et al., 1999).

Cardiac repair: Thymosin Beta-4 has been studied for cardiac repair following myocardial infarction. Animal studies show reduced infarct size, improved cardiac function, and activation of cardiac progenitor cells (Bock-Marquette et al., 2004). A small Phase 1 human trial (RegeneRx) evaluated safety and tolerability in post-MI patients.

Corneal healing: RegeneRx Biopharmaceuticals developed RGN-259, a topical Thymosin Beta-4 formulation for dry eye and corneal injury, which has progressed through multiple clinical trials showing improved corneal healing.

Equine research: TB-500 has been used extensively in equine medicine for tendon and ligament injuries, with reported improvements in healing times and tissue quality. While much of this evidence is veterinary rather than peer-reviewed human research, it provides a substantial body of real-world data.

Hair growth: Animal studies suggest Thymosin Beta-4 plays a role in hair follicle development and may stimulate hair growth, with some users reporting improved hair density as a secondary benefit.

Loading phase: Many research protocols use a loading phase of 4-8 mg per week (split into 2 doses of 2-4 mg) for the first 4-6 weeks to build tissue concentrations.

Maintenance phase: After the loading phase, a maintenance dose of 2-4 mg every 1-2 weeks is commonly described.

Injection sites: TB-500 is typically administered subcutaneously. Unlike BPC-157, it does not need to be injected near the injury site — systemic administration is effective due to TB-500's ability to travel through the bloodstream to areas of injury.

Reconstitution: TB-500 typically comes as a lyophilized powder (2 mg or 5 mg vials). Reconstitute with bacteriostatic water — typically 1-2 mL per vial.

Storage: Store reconstituted TB-500 refrigerated (2-8°C) and use within 2-3 weeks. Lyophilized powder can be stored at room temperature.

TB-500 is generally well-tolerated based on available research and anecdotal reports:

Common side effects: Head rush or lightheadedness shortly after injection, injection site irritation, temporary lethargy or fatigue, and headache.

Theoretical concerns: Like BPC-157, TB-500's promotion of angiogenesis and cell migration raises theoretical concerns about its use in individuals with active cancers, as these mechanisms could potentially support tumor growth and metastasis.

Contraindications: Active malignancies, pregnancy/breastfeeding, and individuals under 18. Caution advised for those on anticoagulant therapy.

The combination of BPC-157 and TB-500 is often called the "Wolverine Stack" due to the perceived synergistic healing effects. The rationale for combining them is that they work through different but complementary mechanisms:

• TB-500 excels at cell migration, bringing repair cells to the injury site, and promoting new blood vessel formation
• BPC-157 excels at growth factor signaling, nitric oxide modulation, and direct tissue protection

Together, they are believed to create a more comprehensive healing response than either peptide alone. Pre-mixed BPC-157/TB-500 blends are available from research peptide suppliers. Typical combined protocols run 4-8 weeks.