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TB-500

Also known as: Thymosin Beta-4, Tβ4, TB4

TB-500 is a synthetic fraction of the naturally occurring thymosin beta-4 protein. It has been studied for its role in cell migration, blood vessel formation, and tissue repair, with particular interest in muscle, tendon, and cardiac tissue regeneration.

Last updated: February 1, 2025Reviewed by: PeptideHub Research Team

TB-500 is a 4,963.44 Da research peptide. TB-500 is a synthetic fraction of the naturally occurring thymosin beta-4 protein. It has been studied for its role in cell migration, blood vessel formation, and tissue repair, with particular interest in muscle, tendon, and cardiac tissue regeneration.

Also called: Thymosin Beta-4, Tβ4, TB4

4,963.44

Molecular Weight

Daltons

1

Strong Evidence

benefits

5

Studies Cited

peer-reviewed

2000-2500

Typical Dose

mcg

Overview

TB-500 is a synthetic peptide representing the active region of thymosin beta-4 (Tβ4), a 43-amino acid protein that is naturally produced by the thymus gland and found in virtually all human and animal cells. Thymosin beta-4 is one of the most abundant intracellular proteins and plays a central role in actin regulation, which is fundamental to cell structure, motility, and division. The synthetic fragment TB-500 consists of the amino acid sequence that is primarily responsible for the protein's tissue-repair properties, specifically the actin-binding domain. Research has focused on its potential to promote cell migration to injury sites, upregulate actin production, reduce inflammation, and stimulate new blood vessel growth. The peptide has been studied across multiple tissue types, including skeletal muscle, cardiac muscle, tendons, ligaments, skin, and corneal tissue. TB-500 has seen particularly notable use in equine veterinary medicine, where it has been used to support recovery from musculoskeletal injuries.

Key Takeaways: TB-500

  • Strongest evidence supports TB-500 for muscle repair & recovery
  • Research doses typically range from 2000 to 2500 mcg via subcutaneous injection
  • 1 benefits with strong evidence, 4 moderate, 1 preliminary
  • Half-life: Estimated 2-3 hours (effects may persist longer due to cellular mechanisms)
  • 5 cited research studies in this guide

Mechanism of Action

TB-500 exerts its effects primarily through upregulation of actin, a cell-building protein critical to cell structure and movement. By promoting actin polymerization, TB-500 facilitates cell migration; the process by which cells move toward injury sites to initiate repair. This is considered its central mechanism. The peptide also promotes angiogenesis (new blood vessel formation), which improves blood supply to damaged tissue and delivers nutrients essential for healing. TB-500 has been shown to reduce inflammatory cytokines, modulating the inflammatory response to prevent excessive tissue damage while maintaining the beneficial aspects of inflammation needed for repair. Additionally, the peptide appears to influence matrix metalloproteinases (MMPs), enzymes involved in tissue remodeling, and may promote the differentiation of stem and progenitor cells into functional tissue-specific cells. Its effects on cardiac tissue have shown particular promise, with research demonstrating activation of cardiac progenitor cells following injury.

Research Benefits

TB-500 at a Glance

Primary mechanism:

TB-500 exerts its effects primarily through upregulation of actin, a cell-building protein critical to cell structure and movement.

Top researched benefits:
Muscle Repair & RecoveryTendon & Ligament HealingAnti-Inflammatory EffectsCardiac RepairWound Healing & Skin RepairHair Growth Promotion

Muscle Repair & Recovery

Strong Evidence

Studies demonstrate accelerated repair of muscle fibers after injury, with improved cell migration to damaged tissue and enhanced regeneration. TB-500 has been shown to reduce recovery time in preclinical muscle injury models.

Tendon & Ligament Healing

Moderate Evidence

Research shows improved healing of connective tissue through enhanced collagen deposition and cellular migration. TB-500 may improve the structural properties of healed tendons compared to untreated controls.

Anti-Inflammatory Effects

Moderate Evidence

TB-500 has demonstrated reduction in inflammatory cytokines and markers, helping to manage the inflammatory response during tissue repair without completely suppressing beneficial inflammation.

Cardiac Repair

Moderate Evidence

Preclinical research has shown thymosin beta-4 can activate cardiac progenitor cells and improve heart function following ischemic injury. Studies in mouse models of myocardial infarction showed improved ventricular function.

Wound Healing & Skin Repair

Moderate Evidence

Animal studies show accelerated dermal wound healing, with improved collagen deposition, angiogenesis, and reduced scarring. TB-500 promotes keratinocyte and endothelial cell migration.

Hair Growth Promotion

Preliminary

Preliminary research suggests thymosin beta-4 may promote hair follicle stem cell migration and differentiation, with observed hair growth stimulation in animal models.

Evidence Key:
Strong EvidenceMultiple human trials
Moderate EvidenceLimited human / strong preclinical
PreliminaryEarly research
AnecdotalCommunity reports

Research Dosing Protocols

Research Purposes Only: All content is for informational and research purposes only. This site does not provide medical advice, diagnosis, or treatment. Consult a qualified healthcare professional before using any peptide or supplement.

Research ProtocolDose RangeRoute
Loading phase (weeks 1-4)20002500 mcgSubcutaneous injection
Maintenance phase20002500 mcgSubcutaneous injection
Acute injury research protocol50007500 mcgSubcutaneous injection

Frequency

2x per week (loading), 1x per week (maintenance)

Timing

Consistent scheduling, often Monday/Thursday or similar spacing

Cycle Length

4-6 weeks loading + 4-8 weeks maintenance

Research Notes

  • 1Loading phase typically involves more frequent administration to achieve tissue saturation.
  • 2Maintenance dosing can be reduced in both dose and frequency after the loading period.
  • 3TB-500 is often paired with BPC-157 in research protocols targeting connective tissue repair.
  • 4Due to its larger molecular size, TB-500 has systemic distribution and is not typically injected near the injury site.
  • 5Equine veterinary use has provided substantial observational data on dosing and effects.

Reconstitution Guide

Standard Reconstitution

Vial Size

5 mg

Bacteriostatic Water

2 mL

Concentration

25 mcg

per 0.1 mL (10 units)

Step-by-Step Guide

1

Gather Materials

TB-500 vial, bacteriostatic water, alcohol swabs, insulin syringes.

2

Equilibrate Temperature

Remove the vial from storage and allow it to reach room temperature (5-10 minutes).

3

Sanitize

Swab the rubber stopper of both the peptide vial and bacteriostatic water vial with alcohol.

4

Draw Water

Draw 2 mL of bacteriostatic water into a syringe.

5

Add Water to Vial

Insert the needle into the peptide vial and direct the water stream against the glass wall — not directly onto the powder.

6

Mix Gently

Swirl the vial gently until the powder is fully dissolved. Never shake. The solution should be clear and colorless.

7

Store Properly

Refrigerate at Refrigerated (2-8°C / 36-46°F) after reconstitution. Up to 30 days refrigerated after reconstitution.

Storage Temperature

Refrigerated (2-8°C / 36-46°F) after reconstitution

Shelf Life

Up to 30 days refrigerated after reconstitution

Important Notes

  • Use bacteriostatic water for multi-use vials.
  • Store lyophilized (unreconstituted) vials frozen (-20°C).
  • Allow the vial to equilibrate to room temperature before adding water.
  • Direct water against the glass wall, not onto the powder.
  • Swirl gently, never shake.
  • TB-500 vials may also come in 2 mg sizes; adjust water volume accordingly.

Safety & Side Effects

Reported Side Effects

  • !Temporary lethargy or fatigue (commonly reported during loading phase)
  • !Head rush or lightheadedness shortly after administration
  • !Injection site discomfort — redness, swelling, or mild pain
  • !Mild nausea (infrequent)
  • !Headache (reported occasionally)
  • !No serious adverse effects reported in published animal studies at standard research doses
  • !Long-term safety data in humans is limited

Potential Interactions

  • May interact with anticoagulant medications due to effects on tissue remodeling pathways.
  • Potential additive effects when combined with other angiogenic compounds.
  • Theoretical interaction with immunomodulatory drugs given thymosin beta-4's immune system origins.
  • Caution with concurrent use of other growth factor-related peptides, overlapping mechanisms.
  • No formal drug interaction studies have been conducted in humans.

Important: Side effects and interactions listed here are compiled from published research and community reports. This is not a complete list. No formal drug interaction studies have been conducted for most research peptides. Always consult a qualified healthcare provider.

Research Studies

The following studies are referenced in this profile. PubMed IDs are provided where available for independent verification.

Thymosin β4 promotes angiogenesis, wound healing, and hair follicle development

Philp D, et al.2004Annals of the New York Academy of Sciences
PMID: 15677399

Demonstrated thymosin beta-4's role in promoting angiogenesis, dermal wound healing, and hair follicle growth through enhanced cell migration and differentiation.

Thymosin β4 activates integrin-linked kinase and promotes cardiac cell migration, survival and cardiac repair

Bock-Marquette I, et al.2004Nature
PMID: 15502815

Landmark study showing thymosin beta-4 promotes survival of cardiac myocytes after ischemic injury through integrin-linked kinase (ILK) activation, with improved cardiac function in mouse models.

Thymosin β4 and cardiac repair

Smart N, et al.2011Annals of the New York Academy of Sciences
PMID: 21276002

Reviewed evidence for thymosin beta-4 in cardiac regeneration, including activation of epicardial progenitor cells and their differentiation into cardiomyocytes following myocardial injury.

Thymosin β4 is an actin-sequestering protein

Safer D, et al.1991Proceedings of the National Academy of Sciences
PMID: 2023929

Foundational paper establishing thymosin beta-4 as the primary G-actin sequestering peptide, explaining its fundamental role in cell motility and cytoskeleton regulation.

Acceleration of wound healing by topical application of thymosin beta-4

Malinda KM, et al.1999FASEB Journal
PMID: 10428762

Demonstrated that topical application of thymosin beta-4 accelerated wound healing in rat models, with enhanced angiogenesis, collagen deposition, and keratinocyte migration.

Note: This is not an exhaustive list of all published research. Studies are selected for relevance and quality. Click PubMed IDs to verify sources independently. Inclusion does not imply endorsement of the peptide for any clinical use.

Frequently Asked Questions

TB-500 is a synthetic peptide that replicates the active region of thymosin beta-4, a naturally occurring protein involved in cell migration, tissue repair, and blood vessel formation. It is studied for recovery and healing applications.

TB-500 is a synthetic fragment of the full thymosin beta-4 protein, containing the key actin-binding and cell migration sequence. The full protein has 43 amino acids while TB-500 represents the most active functional region.

TB-500 and BPC-157 are frequently combined in research protocols. They work through different but complementary mechanisms; BPC-157 promotes local healing and angiogenesis while TB-500 enhances systemic cell migration and actin regulation.

Research protocols typically involve a 4-6 week loading phase with twice-weekly administration, followed by a 4-8 week maintenance phase with weekly or biweekly dosing. Total protocol duration is usually 8-14 weeks.

No. TB-500 is not FDA-approved for any clinical use. It is classified as a research compound. While thymosin beta-4 has been in clinical trials for cardiac and ophthalmological applications, regulatory approval has not been granted.

Unlike some peptides that are injected locally near injury sites, TB-500 is typically administered subcutaneously in the abdominal area or other convenient sites. Its systemic distribution means the injection location is generally not critical.

⚠️

Research & Educational Use Only

All content is for informational and research purposes only. This site does not provide medical advice, diagnosis, or treatment. Consult a qualified healthcare professional before using any peptide or supplement.

The information presented here is compiled from published research studies and is intended for informational purposes only. Individual results may vary. Always consult with a licensed healthcare provider.