What Bronchogen Is
Bronchogen is a synthetic tetrapeptide, C18H30N4O9, 446.46 g/mol, classified within the bioregulator family as respiratory-associated.
One study names it, and it is an unusually direct one.
Research use only. Supplied for laboratory research. Not for human or veterinary use. No marketing authorisation exists and no therapeutic claim is made.
Sequence: AEDL
The sequence is Ala-Glu-Asp-Leu (AEDL). Worth noting because the title of the single published study naming this compound writes it as Ala-Asp-Glu-Leu, with the middle two residues transposed.
Both orderings contain the same residues, so molecular formula and mass are identical either way — C18H30N4O9, 446.46 g/mol. The ordering is not identical, and AEDL is the correct one. The transposition in that paper title appears to be an error at the source, and is flagged here so that anyone comparing our specification against the citation does not read the difference as a discrepancy in the material.
What the Study Reports
The paper measures the effect of the peptide on DNA thermostability (Monaselidze et al., Bull Exp Biol Med 2011, PMID 21240358).
This matters more than a single citation usually would. The family's proposed mechanism is that short peptides interact directly with DNA. A thermostability measurement is a physical test of exactly that: it asks whether the peptide changes the energy required to denature the double helix. It is not a cell study, not an animal study, and not a respiratory study — it is a measurement of the interaction the whole framework is built on.
Read alongside the chromatin work on Livagen and Prostamax, it forms the small set of papers in this family that test the mechanism rather than assume it.
What Is Not Established
Nothing connects Bronchogen to respiratory tissue in the published record. The bronchial association comes from the family classification scheme. No effect on respiratory epithelium, no safety profile, and no amount for any species has been published.
Structure and Handling
- Sequence. Ala-Glu-Asp-Leu (AEDL), tetrapeptide.
- Formula. C18H30N4O9, 446.46 g/mol.
- Form. Lyophilised powder, ≥98% purity, third-party certificate of analysis per batch.
- Storage. Sealed vial at −20 °C, protected from light; reconstituted solution at 2–8 °C.
- Reconstitution. Bacteriostatic water down the vial wall, never onto the powder cake. Do not shake. See the reconstitution calculator.
Related Compounds
Chonluten (Thr-Glu-Asp) carries the same respiratory association and has no study naming it. Full family on the bioregulator overview.
Proposed Molecular Mechanism: Peptide–DNA Interaction
The bioregulator framework advanced by Khavinson and colleagues rests on a specific structural hypothesis: short peptides of two to four residues interact directly with double-stranded DNA, influencing gene expression by altering chromatin accessibility or helix stability rather than by binding a membrane receptor. Bronchogen (AEDL) is positioned within this framework as a putative bronchial-tissue peptide, but its placement is taxonomic — it derives from the classification scheme, not from tissue-distribution experiments.
The single published measurement bearing directly on this mechanism is the differential scanning calorimetry (DSC) study by Monaselidze et al. (2011).[3] DSC measures the enthalpy and melting temperature (Tm) of the DNA helix under defined ionic conditions; a shift in Tm in the presence of a peptide is interpreted as evidence of a thermodynamic interaction between the two molecules. The Monaselidze group applied this approach to several bioregulator tetrapeptides including Bronchogen, reporting a measurable shift in DNA thermostability parameters. This is a physical chemistry result — it does not identify a binding site, does not specify a groove preference (major vs. minor), does not report an affinity constant, and does not connect the interaction to any gene or tissue. The result is consistent with the hypothesis; it does not confirm it at a mechanistic level.
Importantly, the study design does not permit inference about selectivity. The peptide–DNA interaction observed in DSC is a bulk thermodynamic measurement. Whether AEDL preferentially associates with specific sequence motifs, whether the interaction is electrostatic or hydrophobic in character, and whether it is displaced by physiological concentrations of competing cations are all unstudied questions. An analogy to transcription-factor binding or epigenetic modulation — which occasionally appears in secondary literature on this family — goes substantially beyond what DSC data support.
Epistemic status: The peptide–DNA interaction for AEDL is reported in one biophysical model (in vitro DSC, cell-free). No receptor, no binding constant, no downstream gene target, and no cellular model has been reported for this compound. The mechanism is proposed by analogy to the broader bioregulator family; it has not been demonstrated for Bronchogen in any cellular or organismal system.
Comparison with Structurally Adjacent Bioregulator Tetrapeptides
Bronchogen (AEDL) shares three of its four residues with Epithalon (Ala-Glu-Asp-Gly), differing only at position 4 where leucine replaces glycine. This is the closest structural neighbor in the published bioregulator literature, and the contrast is instructive precisely because it illustrates how thin the evidence base is for inferring compound-specific effects from shared residues.
| Compound | Sequence | Putative tissue classification | Published studies (PubMed-indexed, compound named) | DNA/chromatin measurement reported |
|---|---|---|---|---|
| Bronchogen | Ala-Glu-Asp-Leu (AEDL) | Bronchial / respiratory | 1 (DSC, in vitro) | Yes — DSC Tm shift[3] |
| Epithalon | Ala-Glu-Asp-Gly (AEDG) | Pineal / epigenetic aging | Multiple, including rodent longevity and telomerase activation | Yes — telomerase assay and chromatin studies reported |
| Livagen | Lys-Glu-Asp-Trp (KEDW) | Liver / immune | Several; chromatin decondensation in lymphocytes reported | Yes — chromatin accessibility assay |
| Prostamax | Lys-Glu-Asp-Gly (KEDG) | Prostate | Limited; DNA thermostability also examined in same Monaselidze series | Yes — DSC, same series as Bronchogen[3] |
The table makes plain a pattern the individual compound pages can obscure: tissue classification in this family is an organismal-isolation legacy, not a receptor-selectivity observation. Bronchogen was originally derived from bronchial tissue extracts in the Khavinson group's peptide isolation programme; the name and the classification followed from the source material, not from a demonstrated bronchial-specific pharmacology. No binding assay has shown AEDL to preferentially associate with bronchial epithelial receptors over any other cell type, because no such assay has been reported. The single-residue difference between AEDL and AEDG (Leu vs. Gly at position 4) represents a substantial change in side-chain character — leucine is bulky and aliphatic, glycine is minimal and flexible — yet whether this difference produces distinguishable DNA-interaction profiles, distinguishable cellular effects, or distinguishable tissue distribution has not been tested in any published study. Claims of compound-specific respiratory activity for Bronchogen that exceed the DSC measurement therefore rest on classification logic rather than pharmacological evidence.
Research Evidence Landscape: What the Published Record Contains
The evidence base for Bronchogen (AEDL) is, by any standard assessment, extremely narrow. A structured search of PubMed using the terms "Bronchogen," "Ala-Glu-Asp-Leu," and "AEDL peptide" retrieves a single indexed study that names this compound directly: the Monaselidze et al. calorimetric analysis of peptide–DNA interaction (Bull Exp Biol Med, 2011).[4] That paper is documented in the existing sections of this article. No additional indexed trials, no animal dose-response studies, no cell-culture assays, and no pharmacokinetic measurements for Bronchogen as a discrete compound have been located.
The table below reflects this situation without inflation. Where the column value is unknown, it is stated as such rather than inferred from structurally adjacent peptides.
| Study / Year | Model | Compound Tested | Dose / Concentration | Key Finding | PMID |
|---|---|---|---|---|---|
| Monaselidze et al., 2011 | In vitro — differential scanning calorimetry on isolated DNA | Bronchogen (AEDL, named explicitly) | Not specified in the abstract; molar ratio to DNA not reported | Peptide altered DNA thermostability as measured by calorimetric melting profile; direction and magnitude require access to full text | 21240358 |
One row is the correct table for one study. Populating additional rows with data from Epitalon, Livagen, or other Khavinson tetrapeptides would misrepresent those as Bronchogen evidence — which they are not. The implication for researchers is direct: any in-laboratory hypothesis about Bronchogen's biological activity beyond peptide–DNA interaction is currently operating without supporting published data for this compound specifically. That gap is part of the scientific record, not an oversight of this article.
The broader Khavinson bioregulator program has produced published work on several tetrapeptides — Epithalon (Ala-Glu-Asp-Gly), Livagen (Lys-Glu-Asp-Ala), Prostamax (Lys-Glu-Asp-Pro), and others — in a range of models including lymphocyte chromatin, rodent lifespan, and human aging cohorts. That body of work informs the mechanistic framework applied to the whole family, but it does not transfer directly to Bronchogen: each peptide in this class is proposed to have tissue-specific activity, and evidence for one is not evidence for another even when the sequences differ by only one residue.
Regulatory Status and Research Classification
Bronchogen carries no marketing authorisation in any jurisdiction with a publicly searchable regulatory database, including the FDA (Drugs@FDA), the EMA (EPAR database), and the UK MHRA product registry, as of this writing. It is not listed in any pharmacopeial monograph (USP, Ph. Eur., BP). Its CAS number — where assigned — does not appear in a regulatory submission context in publicly accessible records.
In research commerce, short synthetic peptides of this type are generally classified under research chemical or active pharmaceutical ingredient (API) precursor frameworks, depending on jurisdiction, purity specification, and intended use declaration. The relevant regulatory boundary in the United States is the FDA's definition of a drug under 21 U.S.C. § 321(g)(1): a substance intended for use in the diagnosis, cure, mitigation, treatment, or prevention of disease. A tetrapeptide supplied with explicit research-only documentation and without therapeutic labelling does not meet that trigger on its face, but the classification is context-dependent and the supplier bears responsibility for end-use controls.
Bronchogen is not a scheduled substance under the U.S. Controlled Substances Act, and it does not appear on the World Anti-Doping Agency (WADA) Prohibited List by name. However, WADA's S2 category (Peptide Hormones, Growth Factors, Related Substances and Mimetics) is written with a catch-all clause covering substances with similar chemical structure or biological effect; whether AEDL would be captured under that clause has not been formally adjudicated, and researchers working in athletic or anti-doping contexts should seek independent legal review before procurement or use.[5]
For laboratory procurement purposes, the compound is handled as a research-use-only (RUO) material. Certificate of Analysis (CoA) requirements, storage conditions, and purity thresholds appropriate for RUO peptides are described in the Structure and Handling section of this article.
