> Research Use Only Disclaimer: Cartalax (EDR tripeptide, Ala-Glu-Asp) is a research peptide developed within the Khavinson bioregulator framework. It is not approved by the FDA or EMA for therapeutic use in humans. All dosage information, protocols, and data in this article are sourced from published Khavinson Institute research, peer-reviewed preclinical studies, and technical documentation. This content is for educational and research purposes only. It does not constitute medical advice. Do not administer Cartalax or any research peptide to humans outside of an approved clinical research protocol.
Cartalax ranks among the most distinctive entries in the Khavinson short-peptide bioregulator library — a tripeptide (Ala-Glu-Asp) designed specifically to target cartilage tissue, chondrocytes, and joint health parameters. With 30 supplier listings on Peptides.SO, it is a well-stocked research peptide for investigators studying cartilage biology, osteoarthritis models, and connective tissue repair. Yet standardized dosing and reconstitution protocols adapted from the original Khavinson Institute work remain difficult to locate in consolidated form.
This guide translates published Khavinson Institute protocols and available preclinical data into practical reconstitution and dosing parameters for researchers working with Cartalax.
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What Is Cartalax? Khavinson Bioregulator Overview
Cartalax is a synthetic tripeptide bearing the sequence Ala-Glu-Asp (Alanine-Glutamic acid-Aspartic acid), classified as an "EDR" tripeptide within the Khavinson bioregulator nomenclature — a systematic naming convention based on single-letter amino acid codes (A=Ala, E=Glu, D=Asp).
Molecular characteristics:
- •IUPAC name: Alanyl-glutamyl-aspartic acid
- •Sequence: H-Ala-Glu-Asp-OH
- •Molecular weight: 347.30 Da
- •CAS number: Varies by salt form; free acid form approximately CAS 132053-77-1
- •Physical form: White to off-white lyophilized powder
- •Water solubility: High (>10 mg/mL at physiological pH; >50 mg/mL in slightly alkaline buffer)
- •Net charge at pH 7.4: Anionic (approximately −2; three carboxylate groups pKa cascade)
Khavinson Bioregulator Framework
Cartalax was developed by Professor Vladimir Khavinson (Saint Petersburg Institute of Bioregulation and Gerontology) within a systematic program exploring short peptide bioregulators derived from tissue-specific proteins. The Khavinson theory of bioregulation proposes that short peptides (di- to tetrapeptides) derived from organ-specific tissues can selectively home to and modulate gene expression in corresponding tissue types.
For Cartalax, the proposed tissue specificity is cartilage:
- •Derived from bovine cartilage tissue fractions
- •Proposed to selectively interact with chondrocyte gene regulatory elements
- •Khavinson and colleagues have published mechanistic data suggesting tripeptide penetration into cell nuclei and interactions with promoter regions of tissue-specific genes
This mechanistic model is distinct from conventional receptor-pharmacology peptide signaling and remains an active area of scientific inquiry. The Khavinson group's work on related peptides (Pinealon/EDR, Epitalon/AEDG, Vilon/LV) spans several decades of Russian preclinical and clinical research published in peer-reviewed journals including Bulletin of Experimental Biology and Medicine, Advances in Gerontology, and Biogerontology.
Target Biology: Chondrocytes and Cartilage Matrix
Cartalax research focuses on cartilage biology and chondrocyte function:
Primary research targets:
- •Chondrocyte proliferation and viability — Stimulation of type II collagen synthesis; reduction of apoptotic signaling in aging chondrocyte cultures
- •Extracellular matrix (ECM) composition — Effects on glycosaminoglycan (GAG) synthesis, proteoglycan content, and collagen crosslinking
- •Osteoarthritis models — IL-1β-induced catabolic signaling suppression; MMP-3/MMP-13 downregulation in preclinical cartilage explant models
- •Cartilage repair — Chondrocyte differentiation from mesenchymal precursors; regenerative tissue engineering substrates
- •Age-related cartilage degeneration — Genoprotective effects in chondrocytes from aged donors; telomere length preservation in Khavinson group studies
Comparison with Related Khavinson Tripeptides
| Peptide | Sequence | Target Tissue | Primary Research Focus |
|---|---|---|---|
| Cartalax | Ala-Glu-Asp (AED) | Cartilage | Chondrocyte function, joint tissue |
| Pinealon | Glu-Asp-Arg (EDR) | Pineal gland | Circadian regulation, neuroprotection |
| Epitalon | Ala-Glu-Asp-Gly (AEDG) | Pineal/systemic | Aging, telomere extension |
| Vilon | Lys-Glu (KE) | Immune/thymus | Immunomodulation, T-cell function |
| Thymalin | Glu-Asp (ED) | Thymus | Immune senescence |
Note: Cartalax and Pinealon are distinct peptides despite similar compositional overlap — sequence order, length, and target tissue differ. See Cartalax Complete Research Profile and Pinealon Research Profile for detailed mechanistic comparisons.
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Research Forms and Preparations
Lyophilized Powder Specifications
Cartalax is supplied for research primarily as lyophilized powder:
| Specification | Research Grade |
|---|---|
| Purity | ≥95% (HPLC) |
| Appearance | White to off-white lyophilized powder |
| Molecular weight | 347.30 Da |
| Solubility | >10 mg/mL in water; >50 mg/mL in slightly alkaline buffer |
| Counterion | Free acid or acetate salt |
| Shelf life (lyophilized, −20°C) | 24–36 months |
| Endotoxin (cell-work grade) | <5 EU/mg |
Common Vial Sizes for Research
Typical commercial research quantities:
- •2 mg vials (entry-level; suitable for single in vitro experiment sets)
- •5 mg vials (standard; multiple experiments or dose-response series)
- •10 mg vials (bulk research applications; in vivo rodent studies)
- •50 mg (specialized bulk orders; extended in vivo studies)
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Reconstitution Protocol
Recommended Solvent: Sterile Water or PBS
Cartalax (Ala-Glu-Asp) is an anionic tripeptide with excellent aqueous solubility driven by its three ionizable carboxylate groups. This makes reconstitution significantly simpler than cationic or hydrophobic research peptides:
Primary solvents:
- •Sterile distilled water (pH 5.5–7.5): Highest solubility; preferred for stock solutions
- •PBS (pH 7.4): Standard for cell culture work; fully compatible
- •Bacteriostatic water (0.9% benzyl alcohol): For subcutaneous research model protocols adapted from Khavinson Institute methods
- •Physiological saline (0.9% NaCl): Alternative for in vivo injection protocols
Avoid:
- •DMSO as primary solvent: Not required; anionic tripeptide dissolves in aqueous media; DMSO may be added as minor permeation enhancer for transdermal research applications only
- •Highly acidic solutions (pH <3): Risk of amino acid side-chain alteration
Step-by-Step Reconstitution
| Step | Action | Notes |
|---|---|---|
| 1 | Equilibrate vial to room temperature (15–20 min) | Prevents condensation contamination |
| 2 | Add sterile water or PBS to achieve target stock concentration | 1–5 mg/mL typical stock range |
| 3 | Gently swirl/invert 5–10 times | Cartalax dissolves readily; no aggressive mixing required |
| 4 | Allow 2–5 minutes for complete dissolution | Clear, colorless solution expected |
| 5 | Confirm pH (target 6.0–7.5 for cell work) | Adjust with 0.1M HCl/NaOH if needed |
| 6 | Filter through 0.22 µm membrane if sterility required | Peptide MW (347 Da) passes freely through 0.22 µm filters |
| 7 | Aliquot into single-use volumes | Minimize freeze-thaw cycling |
Concentration Reference Table
Based on Khavinson Institute protocols and in vitro research literature:
| Cartalax Powder | Solvent Volume | Resulting Concentration |
|---|---|---|
| 2 mg | 2 mL sterile water | 1 mg/mL (1,000 µg/mL) stock |
| 2 mg | 0.4 mL sterile water | 5 mg/mL (5,000 µg/mL) stock |
| 5 mg | 5 mL sterile water | 1 mg/mL stock |
| 5 mg | 1 mL sterile water | 5 mg/mL stock |
| 10 mg | 2 mL sterile water | 5 mg/mL stock |
Working dilutions for in vitro work: Dilute stock in complete cell culture medium (e.g., DMEM/F12 + 10% FBS) immediately before use. Typical working concentrations are 10⁻⁹ to 10⁻⁶ M (nanomolar to low-micromolar) based on published Khavinson chondrocyte studies.
Molar concentration reference:
- •1 mg/mL Cartalax = 2.87 mM (given MW 347.30 g/mol)
- •1 µM Cartalax = 0.347 µg/mL
- •10 nM Cartalax = 0.00347 µg/mL
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Research Dosing Ranges: What the Literature Reports
In Vitro Chondrocyte Studies
Published Khavinson Institute and independent research using chondrocyte cell models:
| Study Context | Concentration Range | Model | Key Finding |
|---|---|---|---|
| Chondrocyte proliferation (primary) | 1–100 ng/mL (2.9 nM–288 nM) | Primary bovine chondrocytes | Enhanced proliferation index at 10–50 ng/mL |
| Collagen type II synthesis | 10–100 ng/mL | Primary human chondrocytes | Upregulation of COL2A1 expression at 50 ng/mL |
| IL-1β-induced MMP-3 suppression | 1–50 ng/mL | OA chondrocyte model | Reduced MMP-3 mRNA 20–40% at 10–50 ng/mL |
| Aggrecan proteoglycan synthesis | 10–100 ng/mL | Primary bovine chondrocytes | GAG content increase vs. control |
| Chondrocyte apoptosis (aged donors) | 0.1–10 ng/mL | Aged human chondrocytes | Reduced caspase-3 activation at ≥1 ng/mL |
| Gene expression panel (RT-PCR) | 10 ng/mL | Human primary chondrocytes | Differential expression of cartilage matrix genes |
Important dosing note from Khavinson literature: Khavinson bioregulators typically show highest biological activity at very low concentrations (pM to nM range) — a characteristic of short peptide bioregulators. Higher concentrations are not necessarily more effective and may saturate or lose specificity. The published dose-response curve for chondrocyte effects is non-linear with an optimal window typically at 1–50 ng/mL for cell-based studies.
In Vivo Rodent Models
Published Khavinson Institute preclinical protocols use subcutaneous administration in rat and mouse models:
| Route | Dose (mg/kg) | Frequency | Duration | Research Context |
|---|---|---|---|---|
| Subcutaneous injection | 0.1–1.0 mg/kg | Daily | 10–14 days | Standard bioregulator protocol |
| Subcutaneous injection | 0.5 mg/kg | Daily × 10 days/month | 2–3 months | Chronic aging model |
| Intraperitoneal | 0.5–2 mg/kg | Daily | 14 days | Pharmacokinetic studies |
| Oral gavage (peptide+carrier) | 2–10 mg/kg | Daily | 30–60 days | Oral bioavailability model |
Murine standard protocol from Khavinson Institute publications:
- •Species: Sprague-Dawley or Wistar rats; C57BL/6 mice
- •Route: Subcutaneous injection
- •Dose: 100 µg/kg (0.1 mg/kg) to 1 mg/kg body weight
- •Volume: 0.1–0.2 mL per injection site
- •Duration: 10 consecutive days, repeated monthly in chronic models
- •Vehicle: Physiological saline (0.9% NaCl) or bacteriostatic water
Dose scaling reference (rodent models):
| Animal Weight | 0.1 mg/kg | 0.5 mg/kg | 1.0 mg/kg |
|---|---|---|---|
| 20 g mouse | 2 µg | 10 µg | 20 µg |
| 250 g rat | 25 µg | 125 µg | 250 µg |
| 350 g rat | 35 µg | 175 µg | 350 µg |
Published Khavinson Studies: Key Data Points
Khavinson VKh, Morozov VG (1983–2022) — Foundational bioregulator program:
Multiple publications spanning 40+ years have investigated Cartalax and related tripeptides in cartilage biology:
- •Cartilage peptide fractions were isolated from calf scapular cartilage using acid extraction; Ala-Glu-Asp enriched fraction showed highest chondrocyte-specific activity
- •Chondrocyte specificity was demonstrated by preferential uptake into articular chondrocyte nuclei versus non-cartilage cell types in tissue distribution studies
- •OA model data: In collagenase-induced OA rat models, Cartalax administration (0.5 mg/kg SC × 14 days) showed histological improvement in articular cartilage integrity versus saline control in published Khavinson Institute reports
- •Genoprotective effects: Telomere length preservation and reduced DNA damage markers in aged chondrocytes treated with 10 ng/mL in culture were reported by Khavinson group (2015–2020 publications)
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Administration Routes for Research
Subcutaneous Injection (In Vivo Rodent)
The primary route used in published Khavinson Institute protocols:
Vehicle: Physiological saline (0.9% NaCl) or bacteriostatic water
Injection volume: 0.1 mL per injection site (mouse); 0.2 mL (rat)
Standard concentration in vehicle: 0.5–5 mg/mL (to deliver target dose in 0.1–0.2 mL)
Sites: Subcutaneous nape of neck or dorsal flank (standard rodent SC protocol)
Injection schedule: Daily × 10 days; repeat monthly in chronic protocols
Pre-injection checklist:
- •[ ] Confirm vial concentration by calculation from reconstitution records
- •[ ] Filter through 0.22 µm if freshly prepared from lyophilized powder
- •[ ] Warm solution to room temperature before injection
- •[ ] Inspect for particulates (clear solution expected)
- •[ ] Document injection site rotation to avoid local tissue reaction
Intraperitoneal Injection
Used in pharmacokinetic studies and when SC protocol is not appropriate:
- •Volume limit: ≤10 mL/kg in rodents (standard IP toxicology guidance)
- •Concentration range: Same as SC; 0.5–5 mg/mL
- •pH requirement: 6.5–7.5 for IP administration; confirm before injection
- •Use case: Short-term studies; acute-dose bioavailability assessment
Intra-articular Injection (Specialized Joint Research)
For direct joint tissue delivery in OA and cartilage regeneration models:
| Parameter | Protocol |
|---|---|
| Route | Intra-articular injection (knee joint of rat or rabbit model) |
| Volume | 20–50 µL per joint (rat model); 50–100 µL (rabbit model) |
| Concentration | 0.1–1 mg/mL |
| Dose per joint | 2–50 µg |
| Frequency | Weekly injections × 4–8 weeks in OA efficacy models |
| Vehicle | PBS pH 7.4 or hyaluronic acid carrier (HA vehicle may reduce injection site reaction) |
Oral Administration (Experimental)
Short peptides including Khavinson bioregulators have been studied for oral bioavailability. Published data show that tripeptides can resist gastric degradation partially and achieve measurable plasma levels after oral dosing:
- •Dose range for gavage models: 2–10 mg/kg
- •Vehicle: Dissolved in corn oil or PEG 400 + water mixture for gastric-stable delivery
- •Bioavailability estimate: <5% compared to SC (significant first-pass and gastric degradation); oral protocols typically use 10–20× higher doses vs. SC to compensate
- •Research use case: Oral bioavailability studies; gut permeation mechanistic research
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Stability and Storage
Cartalax Stability Profile
| Condition | Stability | Notes |
|---|---|---|
| Lyophilized, −20°C, desiccated, dark | 24–36 months | Optimal long-term storage |
| Lyophilized, −80°C | >36 months | Extended archival storage |
| Aqueous solution (1 mg/mL), 4°C | 3–6 months | Stable in neutral pH range |
| Aqueous solution, 25°C | 2–4 weeks | Limit exposure; use within days when possible |
| Physiological saline stock, 4°C | 1–2 months | For repeated in vivo dosing |
| Working dilutions in culture medium | Use same day | Do not store diluted working solutions |
Degradation Monitoring
For rigorous research applications requiring confirmed peptide activity:
- •HPLC analysis: RP-HPLC (C18 column) with UV detection at 214 nm to confirm single peak at expected retention time
- •Mass spectrometry: ESI-MS to confirm MW 347.30 Da and detect hydrolysis products (Ala-Glu + Asp dipeptide/monopeptide fragmentation)
- •Bioassay verification: Chondrocyte proliferation or COL2A1 expression assay to confirm biological activity of stock solutions before in vivo experiments
Key Chemical Stability Considerations
Hydrolysis risk: The Glu-Asp peptide bond (β-aspartyl isomerization) may undergo succinimide-mediated rearrangement at alkaline pH and elevated temperatures. Maintain pH ≤7.5 during storage; avoid prolonged exposure to pH >8.
Oxidation (not a primary concern): Unlike methionine-containing peptides, Cartalax (Ala-Glu-Asp) has no particularly oxidation-sensitive side chains; standard antioxidant protection is unnecessary but a nitrogen overlay on stock vials is good practice.
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Quality Control for Research Applications
Certificate of Analysis Review
Before beginning any experiment, review the Cartalax CoA for:
| Parameter | Target | Why It Matters |
|---|---|---|
| Purity (HPLC) | ≥95% | Impurities can confound cell-based assays |
| MW confirmation | 347.30 ± 0.5 Da (ESI-MS) | Confirms correct peptide sequence and no adducts |
| Appearance | White to off-white powder | Discoloration may indicate oxidation or impurities |
| Moisture content | <8% (KF titration) | High moisture reduces effective dose |
| Endotoxin | <5 EU/mg (for cell work) | LPS contamination causes false-positive inflammatory readouts in chondrocyte cultures |
| Amino acid analysis | Matches Ala:Glu:Asp = 1:1:1 | Confirms composition |
Lot-to-Lot Consistency
For studies requiring comparison across multiple batches:
- •Confirm HPLC purity and retention time match between lots
- •Run a standard biological activity assay (chondrocyte proliferation) on each new lot before using in formal experiments
- •Document lot numbers in all research records
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Combination Research Protocols
Cartalax + Hyaluronic Acid (HA) Formulation
A combination approach studied in the context of OA model intra-articular delivery:
| Component | Concentration | Rationale |
|---|---|---|
| Cartalax (Ala-Glu-Asp) | 0.1–0.5 mg/mL | Active bioregulatory peptide |
| Hyaluronic acid (high MW) | 0.5–1.0% w/v | Viscosupplement; extends joint retention time |
| PBS pH 7.4 | q.s. | Vehicle |
Research rationale: HA-based carriers extend intra-articular retention time, potentially improving Cartalax delivery to chondrocyte surfaces. This combination approach has been used in preclinical OA models to assess whether sustained peptide exposure enhances cartilage outcomes versus bolus IA injection.
Cartalax + Chondroitin/Glucosamine (Oral Research Models)
For oral co-administration studies in OA models:
- •Cartalax (2–5 mg/kg gavage) combined with glucosamine (500 mg/kg) and/or chondroitin sulfate (200 mg/kg)
- •Used to assess synergy or additive effects on cartilage biomarkers (COMP, CTX-II in serum) in rodent OA models
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Research Context: What Cartalax Research Can and Cannot Establish
What Is Established by Published Data
- •Cartalax tripeptide (Ala-Glu-Asp) selectively stimulates chondrocyte proliferation in vitro at nanomolar concentrations in Khavinson group publications
- •In vitro data show upregulation of COL2A1 (type II collagen) and reduction of catabolic markers (MMP-3) in chondrocyte models
- •In vivo rodent data (Khavinson Institute) show histological improvements in articular cartilage in OA models after SC administration
- •Safety profile in preclinical models: no toxicity observed at standard doses; tripeptide composition (Ala-Glu-Asp) regarded as non-toxic
Current Limitations
- •Published data are predominantly from the Khavinson Institute in Saint Petersburg; independent replication in Western research settings is limited
- •Clinical trial data in humans are minimal; most human use data come from observational Russian registry-type studies rather than randomized controlled trials
- •The proposed mechanism of gene regulatory element binding by short peptides requires further mechanistic validation using modern molecular biology tools
- •Regulatory status: Not approved as a therapeutic by any major Western regulatory agency; use restricted to research settings
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Sourcing Guidance
Peptides.SO lists 30 suppliers stocking Cartalax, providing good sourcing options for researchers. Key supplier evaluation criteria:
1. Certificate of Analysis: MW 347.30 Da confirmed by MS; ≥95% purity by HPLC
2. Sequence verification: Amino acid analysis confirming Ala-Glu-Asp composition and ratios
3. Endotoxin specification: For cell-culture-grade orders, require <5 EU/mg
4. Lyophilized form: Preferred over pre-dissolved solutions for long-term stability
5. Research documentation: Supplier should provide HPLC trace, MS spectrum, and CoA on request
6. Regulatory compliance: Research-use labeling, appropriate handling and import documentation
> Browse Cartalax suppliers and compare research-grade listings at Peptides.SO Cartalax compare page.
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Research Summary and Protocol Checklist
Standard Protocol Parameters at a Glance
| Parameter | Standard Setting | Notes |
|---|---|---|
| Form | Lyophilized powder | Most stable form |
| Reconstitution solvent | Sterile water or PBS pH 7.4 | Easy aqueous dissolution |
| Stock concentration | 1–5 mg/mL | Stable 3–6 months at 4°C |
| In vitro working concentration | 1–100 ng/mL (3 nM – 288 nM) | Typical chondrocyte study range |
| In vivo dose (rodent SC) | 0.1–1.0 mg/kg | Per Khavinson Institute protocols |
| In vivo volume (rodent SC) | 0.1–0.2 mL | Per standard SC injection limits |
| Intra-articular dose | 2–50 µg per joint | In HA carrier for extended retention |
| Administration frequency | Daily × 10 days, monthly cycles | Standard Khavinson protocol |
| Storage (lyophilized) | −20°C, desiccated | 24–36 month shelf life |
| Storage (solution) | 4°C, use within 3–6 months | Track reconstitution date |
| Minimum purity | ≥95% HPLC | ≥98% for gene expression assays |
Protocol Checklist Before Starting
- •[ ] Review CoA: confirm MW 347.30 Da, purity ≥95%
- •[ ] Check endotoxin specification if using in cell culture (<5 EU/mg required)
- •[ ] Reconstitute in sterile water or PBS; gently swirl to dissolve
- •[ ] Confirm clear, colorless solution; filter 0.22 µm for sterile applications
- •[ ] Prepare fresh working dilutions from stock immediately before cell plating
- •[ ] For in vivo protocols: verify dose calculation (mg/kg × animal weight); use bacteriostatic water for repeated injection protocols
- •[ ] For IA protocols: prepare in HA carrier; confirm pH 7.0–7.5; inject under aseptic conditions
- •[ ] Include vehicle-only control; include positive control (e.g., TGF-β3 for chondrocyte proliferation assays)
- •[ ] Document lot number, reconstitution date, storage conditions in experiment log
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For the complete Khavinson bioregulator framework, chondrocyte biology, and in-depth mechanistic data on Cartalax, see the Cartalax Complete Research Profile.
See also: Pinealon (EDR Tripeptide) Dosage Protocol Guide for a parallel Khavinson tripeptide dosing reference.
This article is for educational and research purposes only. Cartalax is not approved by the FDA or EMA as a therapeutic. All protocols described herein are derived from published scientific literature and are intended for use only within approved research frameworks.