Thymosin Beta-4 Fragment (TB-4 Frag)
Also known as: TB4 Fragment · Thymosin Beta-4 Fragment · Ac-SDKP
A synthetic 4-amino acid fragment (Ac-SDKP) derived from the N-terminus of Thymosin Beta-4. This specific fragment is responsible for many of TB-500's anti-inflammatory, stem cell mobilization, and cardiac healing properties, in a more targeted and stable form.
Mechanism of Action
Ac-SDKP is the active N-terminal fragment of TB4 that inhibits the enzyme prolyl oligopeptidase (POP) and prevents T-cell and mast cell proliferation. It mobilizes hematopoietic stem cells, promotes angiogenesis, and reduces cardiac fibrosis. It has been detected as a naturally-occurring peptide in blood and urine.
Benefits
- Anti-inflammatory and anti-fibrotic effects
- Stem cell mobilization
- Cardiac healing and anti-fibrosis
- Reduced mast cell proliferation
- Angiogenesis promotion
- Wound healing
- More stable than full TB-500 molecule
Side Effects & Risks
- Generally well tolerated
- Injection site reactions
- Limited standalone human data (mostly as TB-500)
Where to Buy Thymosin Beta-4 Fragment (TB-4 Frag)
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Storage & Reconstitution Guide
Storage Temperature
-20°C (lyophilized)
24 months (lyophilized), 28 days (reconstituted)
Reconstitution Solvent
Bacteriostatic water (BAC water)
Swirl gently — do not shake or vortex
Handling Notes
Protect lyophilized peptide from moisture and light. Once reconstituted, keep refrigerated. Discard if solution becomes cloudy or discolored. Use insulin syringe for precise dosing.
Step-by-Step Reconstitution
Gather supplies
BAC water, insulin syringe, alcohol swabs, vial
Disinfect tops
Swab rubber stoppers of both vials with alcohol
Draw BAC water
Pull desired mL of BAC water into syringe
Inject slowly
Inject BAC water down the side of the peptide vial, swirl gently to dissolve
Research Protocol
- Dose Range
- 500–1500 mcg
- Frequency
- Once or twice daily
- Cycle
- 4-8 weeks
- Routes
- subcutaneous injectionoral
- Notes
- Fragment of TB-500 with targeted anti-inflammatory/anti-fibrotic effects. Often used in oral capsule blends with BPC-157.
Legal & Regulatory Status
Sold for research purposes only. Not for human use. Laws vary by country.
Commonly Stacked With
View all peptide stacks →External Resources
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