Description

Technical Parameters

Introduction

peptides

product-1400-1400

Products Description

#### **1. Overview**

TB500 (Thymosin β4 synthetic peptide) is a small molecule peptide designed based on the active fragment of thymosin β4 (Thymosin β4, Tβ4), composed of 43 amino acids and a molecular weight of about 4.9 kDa. Tβ4 naturally exists in mammalian cells and participates in processes such as cell migration, angiogenesis, anti-inflammation and tissue repair. TB500, as its synthetic derivative, enhances stability and bioavailability by optimizing the structure and is widely used in the fields of medicine, sports rehabilitation and regenerative medicine.

#### **2. Structural classification and functional characteristics**

Based on structural modification and functional differences, TB500 can be divided into the following categories:

##### **1. Natural analogs (unmodified)**

- **Structural features**: Retains the Tβ4 core sequence (Ac-Ser-Asp-Lys-Pro-Asp-Met-Ala-Glu-Ile-Glu-Lys-Phe-Asp-Lys-Ser-Lys-Leu-Lys-Lys-Thr-Glu-Thr-Gln-Glu-Lys-Asn-Pro-Leu-Pro-Ser-Lys-Glu-Thr-Ile-Glu-Gln-Glu-Lys-Gln-Ala-Gly-Glu-Ser).

- **Advantages**:

- High biological activity, directly mimics the function of natural Tβ4.

- Promotes endothelial cell migration and accelerates wound repair.

- **Limitations**: Short half-life (about 2 hours), frequent dosing required.

##### **2. Synthetic modification (stabilized variant)**

- **Structural modification**: Enhanced stability through acetylation, PEGylation or amino acid substitution (such as Met→Norleucine).

- **Advantages**:

- Extended half-life to 8-12 hours, reducing dosing frequency.

- Improved anti-enzymatic ability, suitable for oral or topical application.

- **Representative variant**: TB500-Fc (fused with immunoglobulin Fc segment), significantly increases blood drug concentration.

##### **3. Functional targeting (coupling type)**

- **Design principle**: Coupling with targeting molecules (such as RGD peptides, antibodies) to enhance tissue specificity.

- **Application scenarios**:

- Myocardial ischemia repair: Targeting heart damage areas.

- Joint inflammation: Local enrichment through hyaluronic acid carriers.

#### **3. Functional application classification**

Based on the main biological activity, the application of TB500 can be divided into the following categories:

##### **1. Tissue repair and regeneration**

- **Mechanism**: Activate actin polymerization, promote cell migration and proliferation.

- **Application areas**:

- **Skin trauma**: Accelerate the healing of burns and chronic ulcers.

- **Muscle injury**: Reduce the recovery time of muscle strain in athletes (clinical data show that the recovery speed is increased by 30-50%).

- **Advantages**: Non-scar healing, reduce fibrosis.

##### **2. Anti-inflammatory and immune regulation**

- **Action pathway**: Inhibit NF-κB signaling, reduce pro-inflammatory factors such as IL-6 and TNF-α.

- **Indications**:

- Arthritis: Relieve synovial inflammation.

- Intestinal inflammation: Relieve the symptoms of ulcerative colitis.

##### **3. Angiogenesis and cardiovascular repair**

- **Mechanism**: Upregulate VEGF expression and promote the formation of new blood vessels

- **Clinical application**:

- Myocardial infarction: Improve blood flow in ischemic areas.

- Peripheral arterial disease: Enhance collateral circulation.

##### **4. Sports medicine enhancement**

- **Function**:

- Reduce muscle inflammation and oxidative stress.

- Enhance tendon flexibility and prevent sports injuries.

- **Controversy**: The World Anti-Doping Agency (WADA) has listed it as a banned substance since 2022.

#### **4. Physical and chemical properties**

##### **1. Basic parameters**

- **Molecular formula**: C₃₄H₅₄N₁₀O₁₂S (core fragment).

- **Molecular weight**: About 4963 Da.

- **Isoelectric point (pI)**: 4.5-5.0, weakly acidic.

##### **2. Solubility and stability**

- **Solubility**:

- Easily soluble in water (≥10 mg/mL, pH 5.0-7.4).

- Slightly soluble in ethanol, insoluble in organic solvents.

- **Stability**:

- Lyophilized state: stored at -20℃ for 2 years, activity retention>95%.

- Solution state: stable for 7 days at 4℃, avoid repeated freezing and thawing.

##### **3. Purity and detection**

- **HPLC purity**: ≥98% (214 nm detection).

- **Quality control indicators**: Endotoxin <0.1 EU/mg, residual solvents meet ICH standards.

#### **5. Color and morphological characteristics**

##### **1. Raw material form**

- **Lyophilized powder**: White or off-white loose solid.

- **Salt type effect**:

- Acetate: pure white, pH 4.5-5.5.

- Hydrochloride: off-white, pH 3.0-4.0.

##### **2. Form of preparation**

- **Injection**: colorless transparent liquid (concentration 1-5 mg/mL).

- **Topical gel**: translucent colloid (containing 0.1-0.5% TB500).

#### **6. Safety and toxicology**

##### **1. Acute toxicity**

- LD₅₀ (rat intravenous injection): >200 mg/kg, a low-toxic substance.

##### **2. Long-term safety**

- 90-day subchronic test: no significant liver and kidney damage (dose ≤10 mg/kg/day).

##### **3. Side effects**

- Local reaction: redness and swelling at the injection site (incidence <5%).

- Systemic risk: high doses may inhibit platelet aggregation (coagulation function needs to be monitored).

#### **7. Future development and challenges**

- **Nano delivery system**: Liposome encapsulation technology can improve transdermal absorption rate.

- **Gene editing combined**: Combined with CRISPR technology to enhance tissue regeneration efficiency.

- **Regulatory barriers**: The regulatory boundaries between medical and enhancement use need to be clarified.

#### **Summary**

As a multifunctional synthetic peptide, TB500 has achieved a leap from basic scientific research to clinical transformation through structural optimization. It has significant application potential in tissue repair, anti-inflammatory and sports medicine, but it needs to balance efficacy and ethical norms. In the future, with the advancement of delivery technology and targeted modification, TB500 may become one of the core tools of regenerative medicine.