GHK, Dalargin and Thymogen in experimental bone fracture: 2021 rat study
M. Yu. Smakhtin, I. I. Bobyntsev, V. T. Dudka, V. Yu. Cherdakov, A. O. Vorvul, A. A. Chulanova, A. M. Smakhtina · 2021 · Humans and their Health / Chelovek i ego zdorovye. 2021;24(4):59–67
Reported findings and study design
Reported findings
Pairwise GHK combinations improved phagocytosis measures in fractured rats. GHK plus Dalargin also showed the strongest oxygen-dependent reserve pattern; GHK alone had a neutral reserve result. Bone repair was assessed descriptively.
Male Wistar rats with experimental femoral fracture; Table 1 lists eight groups, n=8/group; overall cohort flow not separately specified. Eight displayed groups: uninjured saline, fractured saline, three single peptides and three pairwise combinations. Assessments at day 10; local intraosseous exposure.
Dose, route and schedule
Ten-day local intraosseous exposure in the rat study: GHK and Thymogen 0.5 µg/kg, Dalargin 1.2 µg/kg, singly or in pairs. Experimental methods, not a human regimen.
Protocol source ↗ · Original journal PDF, p.60
| Measure | Result | Comparison, timing and statistics |
|---|---|---|
| Phagocytic index: GHK plus Dalargin | 71.3 ± 5.1% versus 30.8 ± 3.1% in fracture controls | Uninjured control 70.7 ± 7.0%; n=8/group; M±m as printed · Day 10 · p<0.05 versus fracture control; Table 1 marks *2 |
| Phagocytosis activation index: GHK plus Dalargin | 2.4 ± 0.3 versus 0.4 ± 0.03 in fracture controls | Uninjured control 2.7 ± 0.2; GHK alone 1.2 ± 0.1; Dalargin alone 1.3 ± 0.1 · Day 10 · p<0.05 versus fracture control; pairwise superiority to single peptides not established by table symbols |
| Oxygen-dependent reserve: GHK alone | No significant increase versus fracture controls; remained below the uninjured reference | Figure 5 group 2 has no fracture-control significance star; no exact bar values digitized · Day 10 · Figure marker indicates p<0.05 versus uninjured animals |
| Oxygen-dependent reserve: GHK plus Dalargin | Increased versus fracture controls; not marked different from the uninjured reference | Figure 5 group 5; this does not establish equivalence to healthy animals · Day 10 · p<0.05 versus fracture control; exact plotted values not extracted |
| GHK plus Thymogen: phagocytic index | 75.3 ± 5.9% versus 30.8 ± 3.1% in fracture controls | This combination also improved uptake; its oxygen-dependent reserve did not show the same restoration pattern as GHK plus Dalargin · Day 10 · p<0.05 versus fracture control; Table 1 |
| Bone repair | More advanced callus remodeling described with GHK combinations; fracture line described as barely visible | Qualitative histology/radiography, not a quantified union-time or strength endpoint · Day 10 |
| Safety and clinical outcomes | No formal adverse-event series, infection-rate reduction or human treatment outcome reported | |
| Assay group sizes | Table 1 and Figure 5 report n=8/group; histology sample flow not separately established |
Table 1: all reported neutrophil phagocytosis results
| Group | Phagocytic index (%) | Phagocytic number | Phagocytosis activation index |
|---|---|---|---|
| Uninjured saline control | 70.7 ± 7.0 | 4.0 ± 0.3 | 2.7 ± 0.2 |
| Fracture + saline | 30.8 ± 3.1 *1 | 1.3 ± 0.1 *1 | 0.4 ± 0.03 *1 |
| Fracture + GHK | 40.7 ± 3.2 *1,2 | 2.7 ± 0.2 *1,2 | 1.2 ± 0.1 *1,2 |
| Fracture + Dalargin | 40.5 ± 3.0 *1,2 | 2.7 ± 0.2 *1,2 | 1.3 ± 0.1 *1,2 |
| Fracture + Thymogen | 53.2 ± 4.1 *1,2 | 2.8 ± 0.2 *1,2 | 1.7 ± 0.1 *1,2 |
| Fracture + GHK/Dalargin | 71.3 ± 5.1 *2 | 3.9 ± 0.3 *2 | 2.4 ± 0.3 *2 |
| Fracture + GHK/Thymogen | 75.3 ± 5.9 *2 | 4.0 ± 0.3 *2 | 2.6 ± 0.2 *2 |
| Fracture + Thymogen/Dalargin | 54.6 ± 5.1 *1,2 | 2.8 ± 0.2 *1,2 | 1.8 ± 0.1 *1,2 |
Original M±m notation; n=8/group, day 10. *1: p<0.05 versus uninjured animals; *2: p<0.05 versus fracture/saline control. Marks retain the original comparison groups. Missing *1 is not proof of equivalence, and these are not monotherapy-versus-combination tests.
This is an original animal study, not a clinical review. Neutrophil uptake and oxygen-dependent reserve are surrogate assays; bone outcomes are descriptive. The claimed synergy lacks a formal interaction test. The 2021 local-delivery study and the 2011 systemic patent belong to a related research program; independent replication or shared animals cannot be established from the available reports.
Source for the extracted data ↗ · Checked 2026-11-07
Molekul summary of the linked publication. Educational information, not medical advice. Seek qualified healthcare help for medical conditions.
Methods, limitations & source review
Study limitations
- Small animal groups; randomization, blinded assessment, power calculation and complete participant flow are not described.
- The numerical endpoints are neutrophil assays, not fracture-union time, mechanical bone strength or clinical infection rates.
- Table significance symbols compare uninjured or fracture controls; they do not establish equivalence to healthy animals or a formal combination-interaction effect.
- Local intraosseous administration differs from the systemic 2011 patent experiment. Shared authors and related models do not establish independent replication; cohort overlap is unresolved.
- The peptide tested was unbound GHK, not GHK-Cu. Pairwise combinations must not be recast as one three-peptide cocktail.
Publication counts are not counts of independent trials. Reviews, translations and reports sharing participants may overlap. Findings apply to the studied preparation, population and endpoints.
Document format: Repository copy of the original nine-page journal article
Review depth: Methods and results text checked; Table 1 (p.64) and Figure 5 (p.65) visually verified against rendered PDF pages
Related-report group: kursk-ghk-dalargin-bone-program. Reports in this group are not assumed to be independent trials.
Source access and review scope
Original PDF recovered through CyberLeninka and checked against publisher-deposited Crossref metadata and the Russian Central Scientific Medical Library abstract. Selected methods, results, Table 1 and Figure 5 reviewed; no independent experimental audit. Received 25 September and accepted 20 December 2021; exact publication day not established.
Recorded source-check date: 2026-11-07. This date does not imply a completed systematic review.
Source type: Original preclinical journal study; not a literature review
Citation and original source
Original source: M. Yu. Smakhtin, I. I. Bobyntsev, V. T. Dudka, V. Yu. Cherdakov, A. O. Vorvul, A. A. Chulanova, A. M. Smakhtina. GHK, Dalargin and Thymogen in experimental bone fracture: 2021 rat study Humans and their Health / Chelovek i ego zdorovye. 2021;24(4):59–67 2021.
Molekul research summary: https://molekul.io/research/ghk-dalargin-bone-2021. Cite the original publication for its findings and this page when referring to Molekul’s summary or evidence appraisal.
Bibliography entryRelated compound profiles
GHK-Cu & GHK family
A single research family collecting GHK-Cu, unbound GHK, Russian terminal extensions, stereochemical variants and related delivery constructs. The member map identifies which molecule each source actually studied; a shared card does not establish interchangeable biological activity.
Dalargin
A Soviet synthetic opioid hexapeptide investigated in cytoprotection, stress, hypoxia, ischemia and trauma. Its enkephalin lineage is distinct from organ-derived peptide bioregulators; historical proposals and laboratory effects are not established clinical indications.
Thymogen
EW is discussed in the thymus-derived research program. Thymalin extract outcomes cannot be assigned to this defined peptide.