TB-500 Fragment (1-4)
Also known as: TB-500 Fragment 1-4, Thymosin Beta-4 Fragment 1-4, TB4 Frag 1-4
TB-500 Fragment 1-4 is the N-terminal tetrapeptide (Ac-SDKP) of thymosin beta-4, studied for anti-fibrotic and tissue-protective effects. This fragment is distinct from the actin-binding region and is associated with regulation of fibrosis and inflammation.
Last updated
Mechanism of Action
Fragment 1-4 corresponds to N-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP), a naturally occurring tetrapeptide released from thymosin beta-4 by prolyl oligopeptidase. Ac-SDKP exerts anti-fibrotic activity by inhibiting TGF-beta and Smad signaling, reducing collagen deposition and fibroblast-to-myofibroblast transition. It also displays anti-inflammatory and pro-angiogenic properties and helps regulate hematopoietic stem cell proliferation.
- Half-life
- Very short; Ac-SDKP is rapidly degraded by angiotensin-converting enzyme
- Administration Routes
- subcutaneous
- Research Status
- Preclinical
Reported Benefits
- Anti-fibrotic activity through TGF-beta and Smad inhibition
- Reduces excess collagen deposition in tissue
- Supports angiogenesis and tissue protection
- Modulates inflammatory responses
- Studied for cardiac, renal, and pulmonary fibrosis models
Potential Side Effects
- Limited human safety data
- Possible injection-site reactions
- Theoretical effects on blood pressure regulation
- Unknown long-term effects
Common Dosing
No validated human protocols exist; preclinical work uses microgram-to-milligram ranges scaled to body weight. For research use only and not personal medical advice.
The dosing information above is aggregated from research literature and anecdotal community reports for educational purposes only. It is not a recommendation, prescription, or medical advice. Peptides are sold as research chemicals only and are not intended for human use.
Contraindications
- Use with ACE inhibitors, which raise endogenous Ac-SDKP levels
- Pregnancy or breastfeeding
- Known hypersensitivity to thymosin-derived peptides
BPC-157
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TB-500
A synthetic version of the active region of Thymosin Beta-4, a naturally occurring peptide that regulates cell migration and tissue repair. Researched for recovery, flexibility, and wound healing.
TB-500 Fragment (17-23)
TB-500 Fragment 17-23 is a short peptide corresponding to the actin-binding region of thymosin beta-4, studied for tissue repair and regeneration. It represents the core bioactive sequence often credited with TB-500's healing effects.
GHK-Cu
A naturally occurring copper-binding tripeptide (glycyl-L-histidyl-L-lysine) widely researched for skin regeneration, collagen synthesis, and wound healing. Common in topical cosmetics.
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Thymosin β4 and its degradation product, Ac-SDKP, are novel reparative factors in renal fibrosis
2013
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Prolyl oligopeptidase is involved in release of the antifibrotic peptide Ac-SDKP
2004
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Decreased endogenous levels of Ac-SDKP promote organ fibrosis
2007
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The Role of Tβ4-POP-Ac-SDKP Axis in Organ Fibrosis
2022