PDRN CareSalmon DNA (Oncorhynchus keta)
Dr. Sarah Chen
PhD, Molecular Biology
Salmon DNA, in the context of skincare and regenerative medicine, refers to polydeoxyribonucleotide (PDRN) extracted from the sperm cells (milt) of Pacific salmon, primarily *Oncorhynchus keta* (chum salmon) and less commonly *Oncorhynchus mykiss* (rainbow trout) [1,2].
Definition
Salmon DNA, in the context of skincare and regenerative medicine, refers to polydeoxyribonucleotide (PDRN) extracted from the sperm cells (milt) of Pacific salmon, primarily Oncorhynchus keta (chum salmon) and less commonly Oncorhynchus mykiss (rainbow trout) [1][2]. The term "salmon DNA" is the popular name used in cosmetics marketing, while PDRN is the precise pharmacological designation for the purified DNA fragments used therapeutically [1].
Source Species
Oncorhynchus keta (Chum Salmon)
The primary source species for pharmaceutical-grade PDRN [1][2]. Chum salmon are chosen for several reasons:
- High DNA yield — Salmon sperm cells contain exceptionally dense, highly polymerized DNA [2]
- Sustainable sourcing — Milt is a byproduct of the commercial fishing and aquaculture industries, making PDRN production environmentally efficient [2]
- Biological compatibility — Salmon DNA shares the same basic nucleotide composition (adenine, thymine, guanine, cytosine) as human DNA, with a similar GC content (~42%) [2]
- Regulatory precedent — O. keta-derived PDRN has the longest regulatory history, with approval in South Korea, Italy, and other markets [1]
Oncorhynchus mykiss (Rainbow Trout)
Used by some European manufacturers as an alternative source. The resulting PDRN is pharmacologically equivalent to O. keta-derived material [2].
Extraction and Purification
The manufacturing process for pharmaceutical-grade PDRN involves multiple purification steps designed to isolate DNA fragments while removing all proteins, lipids, and other cellular components [1][2]:
- Cell lysis — Salmon sperm cells are lysed to release their DNA content
- Protein removal — Enzymatic digestion with proteinase K followed by phenol-chloroform extraction removes all proteinaceous material [2]
- Lipid removal — Organic solvent washes eliminate lipid contaminants
- DNA fragmentation — Controlled enzymatic or mechanical fragmentation produces DNA chains of 50-1500 kDa [1][2]
- Sterilization and quality control — The final product is sterilized and tested for protein content (below detectable limits), endotoxins, and microbial contamination [2]
The purification process is critical because it eliminates the proteins (parvalbumin, collagen) responsible for fish allergies, rendering PDRN non-allergenic despite its fish origin [1][2].
Distinction from Whole Salmon Extract
"Salmon DNA" in skincare marketing sometimes refers to crude salmon-derived extracts that may contain proteins, peptides, and other cellular components alongside DNA [3]. These are pharmacologically distinct from purified PDRN:
- Purified PDRN (pharmaceutical grade) — Defined molecular weight range, no detectable protein, specific A2A receptor activity [1]
- Salmon DNA extract (cosmetic grade) — Variable composition, may contain proteins, undefined mechanism of action [3]
When evaluating products, look for the designation "PDRN," "polydeoxyribonucleotide," or "c-PDRN" rather than generic terms like "salmon DNA extract" or "salmon sperm extract," which may indicate less refined material [1][3].
Pharmacological Significance
The therapeutic value of salmon DNA lies not in its genetic information (the nucleotide sequence is irrelevant to its activity) but in its physical structure as a polymer of deoxyribonucleotides [1][2]. Once in contact with tissue, PDRN fragments serve two distinct functions:
- A2A receptor agonism — PDRN fragments bind to the adenosine A2A receptor, activating signaling cascades that promote fibroblast proliferation, collagen synthesis, angiogenesis, and anti-inflammatory modulation [1][5][6]
- Nucleotide salvage — Enzymatic degradation of PDRN by tissue nucleases releases individual nucleosides and nucleotides, which enter the salvage pathway and serve as building blocks for cellular DNA repair and synthesis [1][2]
Commercial Applications
Salmon DNA-derived PDRN is used across three product categories [1][3][4]:
- Injectable skin boosters — Rejuran Healer, Rejuran S, Nucleofill, Plinest (medical devices for intradermal injection)
- Topical skincare — Serums, creams, ampoules, masks containing PDRN or PN (polynucleotides) as the active ingredient
- Medical applications — Wound healing preparations, orthopedic treatments for cartilage repair, dental healing agents [1][5]
References
- [1]Squadrito F, Bitto A, Irrera N, et al.. Pharmacological Activity and Clinical Use of PDRN. Curr Pharm Des. 2017;23(27):3948-3957. doi:10.2174/1381612823666170516153716
- [2]Veronesi F, Dallari D, Sabbioni G, Carubbi C, Martini L, Fini M. Polydeoxyribonucleotides (PDRNs): From Physical Chemistry to Biological Activities and Clinical Applications. Int J Mol Sci. 2017;18(9):1927. doi:10.3390/ijms18091927
- [3]Colangelo MT, Galli C, Giannelli M. Polydeoxyribonucleotide: A Promising Biological Platform for Dermal Regeneration. Curr Pharm Des. 2020;26(17):2049-2056.
- [4]Kim TH, Kim JY, Bae JH, et al.. Biostimulatory effects of polydeoxyribonucleotide for facial skin rejuvenation. J Cosmet Dermatol. 2019;18(6):1767-1773. doi:10.1111/jocd.12958
- [5]Galeano M, Bitto A, Altavilla D, et al.. Polydeoxyribonucleotide stimulates angiogenesis and wound healing in the genetically diabetic mouse. Wound Repair Regen. 2008;16(2):208-217. doi:10.1111/j.1524-475X.2008.00361.x
- [6]Bitto A, Polito F, Irrera N, et al.. Polydeoxyribonucleotide reduces cytokine production and the severity of collagen-induced arthritis by stimulation of adenosine A2A receptor. Arthritis Res Ther. 2011;13(1):R28. doi:10.1186/ar3254