This article is for informational and educational purposes only and does not constitute medical advice. Cardiogen is supplied by Wholesale Peps as lyophilized research-grade material for in vitro laboratory use only and is not approved by the FDA for human or veterinary use.
Cardiogen is a synthetic tetrapeptide with the sequence Ala-Glu-Asp-Arg (AEDR) and a molecular weight of approximately 489 Da. It belongs to the peptide bioregulator class developed by Vladimir Khavinson and colleagues at the St. Petersburg Institute of Bioregulation and Gerontology, originally derived from research on bovine cardiac tissue extracts. The compound is proposed to function as a cardiac-specific peptide bioregulator with the capacity to modulate gene expression in cardiomyocytes, the contractile cells of the heart. Preclinical studies from the originating research group have reported cardioprotective effects in experimental ischemia models, proposed influences on cardiomyocyte proliferative activity, and potential antiarrhythmic properties in animal preparations. The proposed mechanism is framed within the Khavinson bioregulator hypothesis that short peptides derived from target organ extracts regulate gene transcription through complementary interactions with promoter DNA sequences. As with other members of this compound class, the published evidence base is largely confined to the originating research group, independent replication by external laboratories has not been widely reported in peer-reviewed literature, and no regulatory authority has approved Cardiogen for any clinical indication.
1. Background
1.1 The Peptide Bioregulator Concept
Cardiogen belongs to the Khavinson peptide bioregulator class — a series of short synthetic peptides proposed to regulate gene expression in a tissue-specific manner by interacting with promoter regions of DNA. The theoretical framework, developed beginning in the Soviet Union in the 1970s and continuing through the post-Soviet Russian scientific program, holds that short peptides derived from organ extracts carry sequence-specific information that modulates transcription in the corresponding target tissue. For a broader review of the bioregulator class and its methodological context, see the companion articles on Epitalon (AEDG) and Pinealon (EDR).
Cardiogen was developed as a derivative of a peptide fraction isolated from bovine cardiac tissue. The design principle reflects the broader Khavinson hypothesis that the biologically active peptide signal embedded within a given organ extract can be identified and reproduced as a short synthetic sequence. In Cardiogen’s case, the four-amino-acid sequence Ala-Glu-Asp-Arg was proposed to represent this cardiac-specific regulatory signal. The AEDR sequence shares its first three residues (Ala-Glu-Asp) with the pineal bioregulator Epitalon (Ala-Glu-Asp-Gly), differing only at the fourth position where Arg replaces Gly — a substitution that introduces a basic residue and alters the charge profile of the peptide.
1.2 Cardiac Biology and the Rationale for Organ-Specific Bioregulation
The heart’s contractile cells — cardiomyocytes — are among the most metabolically active and stress-exposed cells in the body, operating under continuous mechanical load and requiring robust mitochondrial energy supply, calcium cycling infrastructure, and protection against ischemia-reperfusion injury. Unlike many cell types, adult mammalian cardiomyocytes have extremely limited intrinsic regenerative capacity: the vast majority are terminally differentiated and exit the cell cycle early in postnatal development, with estimates of annual cardiomyocyte renewal in adult human hearts in the range of 0.5–2% per year.
This limited regenerative capacity means that cardiomyocyte loss — from ischemia, toxic exposure, pressure overload, or aging-related attrition — tends to be irreversible, with lost cells replaced by fibrous scar tissue rather than functional myocardium. The Khavinson group’s rationale for developing a cardiac-targeted bioregulator was grounded in the hypothesis that a peptide derived from cardiac tissue might restore or support cardiomyocyte gene expression patterns associated with protection, function, and, potentially, limited proliferative activity.
2. Molecular Structure
| Property | Value |
|---|---|
| Full name | Cardiogen |
| Sequence (single-letter) | AEDR |
| Sequence (full names) | Ala-Glu-Asp-Arg |
| Molecular weight | ~489 Da |
| Molecular formula | C ₁₈H ₃₁N ₇O ₉ |
| Peptide length | 4 amino acids (tetrapeptide) |
| Net charge (physiological pH) | −1 (two acidic residues at positions 2–3; one basic at position 4) |
| Origin | Synthetic; sequence derived from bovine cardiac tissue extract research |
| Proposed primary target | Cardiomyocyte gene promoter regions (proposed); cardiac tissue-specific transcription |
| Related compound | Epitalon (AEDG) — shares Ala-Glu-Asp N-terminal tripeptide; differs at position 4 |
The net charge of −1 at physiological pH reflects the balance between two acidic side chains (Glu and Asp, each carrying −1 at pH 7.4) and one basic side chain (Arg, carrying +1 due to its guanidinium group with a pKa of approximately 12.5). This charge profile distinguishes Cardiogen from the closely related Epitalon sequence (AEDG), which carries a net charge of −2 because glycine at position 4 contributes no side-chain charge. The partial internal charge balance in Cardiogen has been proposed as relevant to its proposed DNA-binding mode within the Khavinson framework, though specific structural evidence for peptide-promoter interactions in cardiomyocytes has not been published from independent structural biology laboratories.
3. Proposed Mechanisms of Action
4. Key Research Findings
4.1 In Vitro Cardiomyocyte Studies
The primary in vitro evidence base for Cardiogen centers on studies using isolated cardiomyocyte preparations and cardiac cell culture models. The Khavinson group has reported that Cardiogen treatment in these systems is associated with changes in markers of cell viability, proliferative activity (including Ki-67 positivity and other cell cycle markers), and expression of structural cardiomyocyte proteins such as components of the sarcomere and contractile apparatus [1]. These in vitro observations form the mechanistic foundation for the proposed cardioprotective and regenerative hypotheses associated with the compound.
As with other members of the Khavinson bioregulator class, a consistent feature of this in vitro literature is that the studies originate predominantly from a single research group, using reagents and methods developed within that group. Replication of key findings by independent cardiac biology laboratories using standard contemporary methods — including quantitative gene expression profiling, single-cell analysis, and live-cell imaging of cardiomyocyte behavior — has not been widely reported in peer-reviewed literature.
4.2 Animal Cardiac Models
Animal model studies from the Khavinson group have examined Cardiogen in experimental preparations designed to model cardiac ischemia and arrhythmia. In rodent ischemia models, Cardiogen treatment was reported to be associated with attenuated markers of myocardial damage, reduced arrhythmia incidence following pharmacological provocation, and improvements in functional cardiac indices relative to control animals [2]. Additional studies have examined cardiomyocyte morphology and histological markers in cardiac tissue from treated animals.
These animal data represent the most experimentally complex tier of evidence for Cardiogen, moving beyond cell culture toward integrated organ and whole-animal physiology. However, the rodent cardiac ischemia models used in this literature differ substantially from the heterogeneous etiology, comorbidity burden, and treatment context of human cardiac disease. All reported animal studies have been conducted by the originating research group, and independent replication in animal models by external cardiac physiology laboratories has not been published.
Schematic representation of evidence depth at each research stage. Bar lengths are qualitative, not derived from a numerical index. Independent replication in each category is absent or minimal as of the review date.
4.3 Published Human Data
Published human data relevant to Cardiogen are very limited. The Khavinson group has included cardiac bioregulators alongside other compounds in broader observational reports examining bioregulator peptide use in clinical populations, but controlled human trials with Cardiogen as the primary intervention and cardiac endpoints as pre-registered primary outcomes have not been identified in peer-reviewed literature accessible to this review [3].
No peer-reviewed, randomized, placebo-controlled trial of Cardiogen in human subjects has been identified as of the review date. The absence of controlled human trial data means no assessment of safety, tolerability, pharmacokinetics, or cardiac efficacy in human subjects can be drawn from the published evidence. Human cardiovascular outcomes — the endpoints most relevant to a compound targeting cardiomyocyte biology — have not been evaluated in this compound at the controlled trial level.
5. Evidence Status
| Proposed Effect | Current Status | Evidence Level |
|---|---|---|
| Cardiomyocyte gene expression modulation | Reported in vitro by Khavinson group; no independent replication published | Limited |
| Cardiomyocyte proliferative marker induction | In vitro observations from originating group; functional significance not established | Limited |
| Cardioprotection in ischemia models | Animal model data from Khavinson group; no independent replication | Limited |
| Antiarrhythmic properties (experimental) | Animal preparation data; single group; mechanism not characterized | Limited |
| Human cardiac outcomes | No controlled trials identified; no RCT data | Not Established |
| Sequence-specific promoter binding (AEDR) | Computational modeling only; no independent structural validation | Limited |
| Human pharmacokinetics / safety | Not characterized in published studies | Not Established |
What We Still Don’t Know
- Whether cardiomyocyte gene expression effects are reproducible by independent investigators: All published observations of Cardiogen’s effects on cardiomyocyte gene expression and proliferative markers originate from the Khavinson group. Independent replication using contemporary transcriptomic, proteomic, and live-cell methods is necessary to validate these findings.
- Whether any cardiomyocyte proliferation is functionally meaningful: Even if Cardiogen induces cell cycle marker expression in cardiomyocytes in vitro, the question of whether adult cardiomyocytes actually complete productive cell division and form functional new contractile units — as opposed to entering abortive cell cycle attempts that do not result in new cells — has not been resolved by the published evidence.
- Whether animal ischemia model results translate to human cardiac disease: Rodent cardiac ischemia models differ from human myocardial infarction and ischemic cardiomyopathy in important ways, including heart rate, metabolic substrate utilization, collateral circulation anatomy, and the comorbidity burden typical of patients with human cardiac disease. Translation of Cardiogen’s animal data to human cardiac efficacy is therefore uncertain.
- The molecular mechanism linking AEDR to cardiac protection: No independent published study has mapped the intracellular signaling pathway connecting AEDR to any reported cardiomyocyte effect — whether through receptor-mediated signaling, chromatin interaction, epigenetic modification, or another route.
- Pharmacokinetics in humans: For a tetrapeptide of ~489 Da without protective modifications, rapid proteolytic degradation in plasma is expected following parenteral administration, and oral bioavailability is expected to be negligible. Whether sufficient intact Cardiogen peptide reaches cardiac tissue in concentrations relevant to the proposed mechanism has not been established in published pharmacokinetic studies.
6. Limitations of Current Research
References
- Khavinson VKh, Linkova NS, Polyakova VO, Kvetnoy IM. “Biological activity of short peptides and their role in regulation of functions of the pineal gland and myocardium.” Bulletin of Experimental Biology and Medicine. 2011;152(1):114–117. doi:10.1007/s10517-011-1470-6
- Khavinson VKh, Malinin VV. “Gerontological Aspects of Genome Peptide Regulation.” Basel: Karger; 2005. Monograph covering the peptide bioregulator class including cardiac tetrapeptide research.
- Anisimov VN, Khavinson VK. “Peptide bioregulation of aging: results and prospects.” Biogerontology. 2010;11(2):139–149. doi:10.1007/s10522-009-9249-8
- Khavinson VKh, Morozov VG. “Peptides of pineal gland and thymus prolong human life.” Neuro Endocrinology Letters. 2003;24(3–4):233–240. PMID:14523363 [Observational human data from the Khavinson group encompassing multiple bioregulator peptides including cardiac preparations.]
- Bergmann O, Bhardwaj RD, Bernard S, Zdunek S, Barnabé-Heider F, Walsh S, Zupicich J, Alkass K, Bhardwaj RD, Druid H, Jovinge S, Fr�sen J. “Evidence for cardiomyocyte renewal in humans.” Science. 2009;324(5923):98–102. doi:10.1126/science.1164680 [Background reference establishing the limited renewal rate of human cardiomyocytes used as biological context throughout this article.]