Crystagen Research, Specifications & Scientific Information

Introduction

Crystagen has the smallest published record of any compound on this list: two primary papers, both in excised tissue, and a name-to-sequence identification that runs through a single review table.

Two verifiable primary sources is the floor this library publishes at, and this compound sits exactly on it. The page is therefore short, and it is short on purpose — padding it would mean writing sentences that nothing supports, which is the failure this programme exists to avoid.

The two papers are worth reading against each other, because they split. One names the compound and reports that it activates the B-cell arm of the immune system in ageing spleen but does not affect cell renewal there ^[1]. The other gives its sequence under a laboratory code and reports that it stimulated proliferation in skin explants from young rats, alongside three of four siblings ^[2]. Neither reports an interaction, a target, or a measurement in an intact organism.

The family's shared limitations apply in a concentrated form and are stated once here. One originating research programme; both papers Russian in origin and one Russian-language; small studies; no whole-animal work on this compound located; no clinical report of any design; and no independent replication of anything.

What Is Crystagen?

A synthetic tripeptide with free termini, EDP in single-letter code: L-alpha-glutamyl-L-alpha-aspartyl-L-proline. PubChem carries the sequence as compound identifier 145455337.

The identification is worth stating carefully, because it is thinner than for the other compounds on this list. The trade name Crystagen is linked to the sequence Glu-Asp-Pro in one published source: the originating group's 2022 transporter review, whose table lists them together ^[3]. The PubChem record for Glu-Asp-Pro does not carry the trade name among its synonyms. The one experimental paper that states the sequence uses only the laboratory code T-36 ^[2]. The one paper that uses the trade name never gives a sequence ^[1]. The chain holds, and it is one link long — which is a fact about the record rather than a doubt about the compound, and it is stated here so that a reader can weigh it.

Within the series the compound is listed as an immunoprotector, and that attribution in the review table is referenced to a patent rather than to a published study ^[3]. A patent is a claim of invention examined for novelty; it is not a result examined by peers.

Crystagen has not been approved by the U.S. Food and Drug Administration for any indication. No marketing application is on record in the United States, and no study of it appears on ClinicalTrials.gov.

Crystagen Specifications

PubChem carries the free tripeptide as compound identifier 145455337, formula C14H21N3O8 and an average mass of 359.33 g/mol. No CAS registry number and no FDA/NCATS unique ingredient identifier resolve for it, so both fields are published as unknown rather than estimated — this is the most thinly registered compound in this batch. The identification of the trade name Crystagen with the sequence Glu-Asp-Pro rests on a single published source, the originating group's 2022 transporter review, which lists the two together; the PubChem record for the sequence does not carry the trade name as a synonym. The laboratory code T-36 is the label used in the one experimental paper that gives the sequence explicitly. The C-terminal proline restricts backbone rotation, removes a backbone amide hydrogen, and permits cis as well as trans configuration of the preceding peptide bond, so material of a single sequence can exist as two slowly interconverting conformers.

Values that a public register does not carry are shown as not publicly characterised rather than estimated. Identifiers are reference values; the certificate of analysis supplied with a laboratory order is the record for a given lot.

How Does Crystagen Work?

Not established, and the record for this compound is emptier than for any other page in this batch.

No receptor has been identified and none is proposed. The specification table shows primary target, receptor family and agonist status as not publicly characterised, and those entries are accurate rather than unfinished.

No binding study of this tripeptide exists. The originating group's general hypothesis for the series is direct interaction with nucleic acids or with histones, and that hypothesis has been tested by fluorescence quenching, differential scanning calorimetry and molecular docking for Epitalon, Pinealon, Bronchogen, Testagen, Cardiogen and others. No such experiment on Glu-Asp-Pro has been located. Whatever support the series' mechanistic hypothesis has, none of it is specific to this compound.

What the two papers measure are cell populations. B-cell activation without accompanying cell renewal in ageing spleen tissue; proliferation in skin explants from young rats ^{[1, 2]}. Both are several steps downstream of any molecular event, and neither paper attempts the intervening steps.

No transport, no pharmacokinetics, no whole-animal study. In both experiments the peptide was applied to excised tissue in culture.

Crystagen Mechanism of Action

In vitro research

Immunoprotective effects in ageing spleen. Four short peptides were compared: Vilon, Thymogen, this compound and a peptide designated R-1. Vilon and R-1 were reported to activate T-helper cells, Vilon through reduced apoptosis and R-1 through increased proliferation and differentiation. Thymogen was reported to activate B-lymphocytes by reducing apoptosis and increasing proliferation of spleen cells. This compound was reported to activate the B-cell arm of the immune system as well — but not to affect the processes of cell renewal in the spleen as it ages ^[1].

The qualification is the substance of the result. Four peptides producing four described profiles, one of them with an explicit exception attached, is a more discriminating report than a summary that credits all four with the same effect. The indexed abstract gives no group sizes, no concentrations, no statistical detail and no explicit statement of whether the spleen tissue was examined in culture or in intact animals; the study design and the authorship both point to explant culture, and this page places it under the in vitro tier on that basis rather than claiming an animal result it cannot support.

Organotypic skin explants under laboratory codes. Five synthesised tripeptides were tested in organotypic skin cultures from young and old rats: T-32 (Glu-Asp-Ala), T-33 (Glu-Asp-Arg), T-34 (Glu-Asp-Gly), T-36 (Glu-Asp-Pro) and T-38 (Lys-Glu-Asp). In explants from young rats, all peptides except T-34 — which is Chonluten — stimulated cell proliferation. In explants from old rats, only T-38 produced a marked stimulatory effect. Immunocytochemistry for the proapoptotic p53 protein indicated that increased proliferation came with less pronounced apoptosis ^[2].

Read for what it says about this compound specifically: it acted in young tissue and was not among those singled out for acting in old tissue. For a series whose defining claim is geroprotection, being active in young explants and not named among the active ones in old explants is a limited result, and it is the only experimental result available that states this compound's sequence.

Findings in this section were obtained in excised tissue in culture. None of them establishes anything about an intact animal, and none about a person.

What Is Crystagen Being Researched For?

Two things, once each.

• Immunoprotection in ageing spleen tissue — B-cell activation, with cell renewal explicitly unaffected ^[1].
• Proliferation in organotypic skin explants — under the laboratory code, alongside four sibling tripeptides ^[2].

No other research area has an identifiable primary literature for this compound. The immunoprotective role listed for it in the originating group's review table traces to a patent rather than to a study ^[3], and is therefore not described here as a research area in its own right.

None of that is research into, or evidence about, research-grade material supplied for laboratory use.

Current Research Status

Status as of September 22, 2026. This block is rendered from maintained fields, not from prose, so it cannot go stale in one place and stay current in another.

Crystagen vs Related Compounds

Cortagen :: Ala-Glu-Asp-Pro — this exact sequence with an alanine added at the front, and assigned to brain cortex rather than immune tissue. A tripeptide and its own N-terminal extension placed in different organs is the series' premise at its most demanding, and no experiment testing the two against each other has been located. Prostamax :: Lys-Glu-Asp-Pro — the same sequence extended with lysine instead, and assigned to prostate. The three compounds share a C-terminal Glu-Asp-Pro and are held to act on three different tissues. Pinealon, Chonluten and Vesugen :: T-33, T-34 and T-38 in the coded literature — the three tripeptides tested beside this one in the skin explant experiment, where T-34 was inactive in young tissue and T-38 was the only one singled out as active in old tissue ^[2]. Vilon and Thymogen :: The two named comparators in the spleen study, each reported with a different immunological profile from this compound and from each other ^[1].

Evidentiary position

Not approved by the U.S. Food and Drug Administration, no registered trial, no clinical report of any design, no whole-animal study located, no binding study of any kind, and two primary papers in total.

No comparison of effect between these compounds is made on this page.

Chemical & Molecular Characteristics

Proline governs the shape of this molecule. It is the only standard amino acid whose side chain closes back onto its own backbone nitrogen. That removes a backbone amide hydrogen the peptide would otherwise use to donate a hydrogen bond, restricts rotation about the preceding bond, and permits that bond to adopt a cis as well as the usual trans configuration. A single pure sequence can therefore exist as two slowly interconverting conformers — which in practice can show as a broadened or split chromatographic peak for material that is genuinely one compound, and is a common cause of a purity figure being read as impurity.

Charge is strongly acidic. The glutamate side chain, the aspartate side chain and the proline C-terminal carboxyl give three acidic groups against a single N-terminal amine, with no basic side chain anywhere. At physiological pH the molecule is net negative and very water-soluble, with no meaningful hydrophobic surface.

Reversed-phase retention is poor. A 359-dalton peptide of this polarity is weakly retained on conventional C18 and can elute near the void volume alongside salts and synthesis-related impurities. A bare "purity by HPLC" figure carries little information for this compound without the method behind it.

No aromatic residue, so no absorbance at 280 nm. Quantification relies on peptide-bond absorbance near 214 nm, where buffers and solvents also absorb.

Adjacent acidic residues make isomerisation the identity question. Glutamate followed directly by aspartate is the motif most prone to alpha/beta and alpha/gamma rearrangement under heat and acid, and the rearranged species have the same molecular formula and the same mass as the intended compound. Combined with the cis/trans proline question, this is a molecule with two distinct kinds of heterogeneity that a mass measurement cannot see.

Both register identifier fields are empty. No CAS registry number and no FDA/NCATS unique ingredient identifier resolve for this tripeptide; only the PubChem compound identifier 145455337 does. They are shown as unknown above rather than filled from a neighbouring substance. For a compound whose trade-name identification also rests on one source, the practical consequence is that a certificate of analysis carrying a registry number for material sold under this name is worth checking rather than assuming.

Frequently Asked Questions

Scientific References

1. Сhervyakova NA, Linkova NS, Chalisova NI, et al.. [Molecular aspects of immunoprotective activity of peptides in spleen during the ageing process] Advances in gerontology = Uspekhi gerontologii; 2014. PMID 28976144
2. Voicekhovskaya MA, Chalisova NI, Kontsevaya EA, et al.. Effect of bioregulatory tripeptides on the culture of skin cells from young and old rats Bulletin of experimental biology and medicine; 2012. PMID 22803085 doi:10.1007/s10517-012-1527-9
3. Khavinson V, Linkova N, Kozhevnikova E, et al.. Transport of Biologically Active Ultrashort Peptides Using POT and LAT Carriers International journal of molecular sciences; 2022. PMID 35887081 doi:10.3390/ijms23147733

Every identifier above is resolved against PubMed, Crossref or ClinicalTrials.gov at build time, and the title returned by the register is compared with the title stored here. A page does not publish if a reference fails to resolve.

Research-Use Information

For in vitro research use only. This material is a laboratory reagent. It is not a drug, food, dietary supplement, or cosmetic and is not for human or veterinary use, including ingestion, injection, or any other administration. No information on this page describes or implies any effect in humans or animals. Sold only to researchers under our Terms of Sale.