-15%Thymosin Beta 4 (Frag 1-4) Capsules
60 capsules · Ac-SDKP Fragment · Active TB-500 Fragment · Limitless Life Nootropics
Price with PeptideDeck coupon applied at checkout
PeptideDeck
≥98% Purity
Third-party verified
60 Capsules
Convenient oral form
GMP Compliant
USA manufactured
Active TB-500 Fragment
N-terminal Ac-SDKP
About TB4 Fragment 1-4
Thymosin Beta 4 Fragment 1-4, also known as Ac-SDKP (N-acetyl-seryl-aspartyl-lysyl-proline), is the bioactive N-terminal tetrapeptide derived from the full-length Thymosin Beta 4 (TB-500) protein. It is naturally produced in the body when prolyl oligopeptidase (POP) cleaves TB-500. Ac-SDKP is a well-characterized endogenous peptide with potent anti-fibrotic, anti-inflammatory, and stem cell mobilizing properties. It has been extensively studied for its role in cardiac repair, tissue remodeling, and the regulation of hematopoietic stem cell proliferation.
Product Specifications
Recommended Dosage
Key Benefits
Tissue Repair & Wound Healing
TB4 Frag 1-4 (Ac-SDKP) promotes endothelial cell migration and differentiation, accelerating tissue repair. It enhances wound closure by stimulating fibroblast activity and supporting extracellular matrix remodeling.
Anti-Fibrotic Effects
Ac-SDKP is a potent anti-fibrotic peptide that inhibits collagen deposition in multiple organs. It prevents and reverses fibrosis in cardiac, renal, and hepatic tissue by suppressing TGF-β/Smad signaling pathways.
Cardiac Repair & Protection
Ac-SDKP protects the heart after ischemic injury by reducing inflammation, limiting scar formation, and promoting angiogenesis in damaged cardiac tissue. It is especially beneficial for post-myocardial infarction recovery.
Anti-Inflammatory Activity
TB4 Frag 1-4 modulates inflammatory responses by inhibiting macrophage activation and reducing pro-inflammatory cytokine release. It helps regulate the balance between inflammation and tissue repair processes.
Stem Cell Mobilization
Ac-SDKP stimulates the proliferation and migration of stem and progenitor cells. It plays a key role in hematopoietic stem cell regulation and promotes bone marrow-derived cell recruitment to sites of tissue damage.
How TB4 Fragment 1-4 Works
TB4 Fragment 1-4 (Ac-SDKP) exerts its biological effects through several well-documented mechanisms. As a potent anti-fibrotic agent, it inhibits the differentiation of fibroblasts into myofibroblasts and reduces collagen synthesis by suppressing the TGF-β/Smad signaling pathway. This makes it highly effective for conditions involving excessive tissue scarring.
Ac-SDKP also plays a critical role in stem cell regulation. It acts as a negative regulator of hematopoietic stem cell entry into S-phase, helping maintain the quiescent stem cell pool. Additionally, it promotes the mobilization and migration of bone marrow-derived stem and progenitor cells to sites of tissue injury, supporting endogenous repair mechanisms.
The peptide promotes angiogenesis by stimulating endothelial cell proliferation, migration, and tube formation. Ac-SDKP provides protective effects after myocardial infarction by reducing fibrosis, promoting new blood vessel formation, and limiting inflammatory damage. It is naturally regulated by ACE, which is why ACE inhibitors elevate endogenous Ac-SDKP levels.
Frequently Asked Questions
What is TB4 Frag 1-4 vs full TB-500?
TB4 Fragment 1-4 (Ac-SDKP) is the active N-terminal tetrapeptide derived from the full 43-amino-acid Thymosin Beta 4 (TB-500) protein. While full-length TB-500 has broad biological activity, the Ac-SDKP fragment specifically concentrates the anti-fibrotic, stem cell mobilization, and tissue repair properties. It is naturally produced in the body when TB-500 is cleaved by prolyl oligopeptidase (POP).
How does oral TB4 Fragment compare to injectable?
Oral TB4 Fragment capsules offer convenience and ease of use compared to injectable forms. While injectable TB-500 provides direct systemic bioavailability, oral Ac-SDKP is a small tetrapeptide that absorbs well through the gastrointestinal tract. Oral capsules are ideal for those who prefer a non-invasive administration route.
Can TB4 Fragment be combined with BPC-157?
Yes, TB4 Fragment 1-4 and BPC-157 are frequently combined for comprehensive tissue repair. BPC-157 primarily supports gut healing and tendon/ligament repair via the nitric oxide pathway, while Ac-SDKP provides anti-fibrotic and stem cell mobilization effects. Together they target complementary repair mechanisms.
How should TB4 Fragment capsules be stored?
Store at room temperature in a cool, dry place away from direct sunlight and moisture. Refrigeration is not required but can extend shelf life. Keep the container tightly sealed between uses. Properly stored capsules maintain potency for the duration of the labeled shelf life.
Is Ac-SDKP found naturally in the body?
Yes. Ac-SDKP is an endogenous peptide naturally present in human plasma and tissues. It is continuously produced from Thymosin Beta 4 by the enzyme prolyl oligopeptidase (POP) and degraded by angiotensin-converting enzyme (ACE). Plasma levels of Ac-SDKP are elevated in patients taking ACE inhibitors, which is believed to contribute to some of their anti-fibrotic benefits.