How Polynucleotides Actually Work: The Science Behind the Results

Polynucleotides, also known as PDRN or polydeoxyribonucleotides, are long-chain DNA fragments extracted and purified from salmon sperm cells. I know that sentence sometimes produces a reaction in the consultation room. Let me explain why it should not.

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Salmon DNA shares a remarkably high structural similarity with human DNA. The fragments used in treatment are not cells, not organisms, not anything biologically active in their own right once extracted. They are purified nucleotide chains that our own cellular machinery recognises and processes as if they were endogenous. The purification process removes proteins entirely, which is why adverse reactions are rare to the point of being clinically unusual.

The critical distinction from almost every other injectable treatment is this. Polynucleotides do not add volume. They do not fill space. They do not freeze muscle activity or create an injury response. Instead, they communicate directly with the cells in your dermis, triggering a biological cascade that instructs those cells to behave as they did when you were younger. This is molecular signalling. Not filler. Not damage repair. Something categorically different.

A 2025 comparative review published in PMC confirms that PDRN selectively activates the adenosine A2A receptor, a process that modulates inflammation, stimulates angiogenesis, and enhances collagen production in dermal fibroblasts. The evidence base spans decades. This is not an emerging hypothesis. It is an established mechanism.

What is actually happening in your skin

The biological timeline of polynucleotide treatment is the part of my consultations that patients find most engaging, possibly because I cannot help becoming genuinely animated when I explain it. This is the science that won me over.

In the first hours after injection, the polynucleotide gel disperses through the dermis. You will see small raised blebs at

the injection points. These are a distribution pattern, the product settling into tissue planes. There is no aesthetic change and there should not be. This treatment asks you to wait, and the waiting is doing something.

Over the first week, your own endogenous DNase enzymes begin breaking the long polynucleotide chains into smaller fragments. This is the part most practitioners do not explain clearly enough. The breakdown is not the treatment wearing off. It is the treatment beginning. The enzymatic digestion creates the bioactive nucleotide fragments that drive everything that follows. Nature has designed a sustained-release mechanism, and the product works with it rather than around it.

Somewhere between day three and day fourteen, those smaller fragments bind to adenosine A2A receptors on the surface of dermal fibroblasts, the cells responsible for producing collagen and elastin.

This is the moment that separates polynucleotides from every injury-based collagen treatment. Research published in PMC confirms that A2A receptor activation simultaneously reduces inflammatory infiltration, promotes fibroblast differentiation and maturation, and upregulates VEGF to support new blood vessel formation. A coordinated biological response. Not a wound signal.

That last point is worth dwelling on, because it is the most clinically significant distinction in the whole treatment category. Radiofrequency, lasers, chemical peels: all of these work by creating controlled tissue damage.

The body responds to that damage by producing collagen as part of a wound-healing response. The collagen is structurally adequate, but it is scar-type collagen. Disorganised. Less functionally optimal than what a healthy fibroblast produces when properly signalled. Polynucleotides bypass injury entirely. The collagen produced through A2A receptor activation is structured, organised, and functionally equivalent to what your dermis generates naturally in youth.

Over the following weeks, the fibroblasts activated by this process increase protein synthesis. Growth factors released during this cascade stimulate surrounding cells, amplifying the effect well beyond the direct injection points. By weeks four to twelve, new collagen and elastin are forming structured networks in the dermis.

Naturally produced hyaluronic acid integrates into the extracellular matrix. Skin visibly thickens, firms, and smooths. This is not oedema resolving. This is genuine structural change at the dermal level, and it continues even after the polynucleotide itself has been metabolised, because the cells it activated remain in a heightened state of function.

Three things most practitioners do not mention

The timeline above is what good practitioners explain. But three additional mechanisms place polynucleotides in a fundamentally different category to conventional skin boosters, and they deserve more attention than they typically receive.

The first is what happens to senescent fibroblasts. As we age, fibroblasts do not die. They enter a state of cellular senescence, a kind of biological retirement where they stop responding to normal signalling and contribute nothing to collagen production. They are present. They are just no longer participating.

Research published in PLOS ONE demonstrated that PDRN treatment mitigates senescence induced by UVB and oxidative stress, restoring migration capacity and activity in these dormant cells. A related PMC study found the effects particularly consistent in donors over sixty, directly suggesting a selective benefit precisely where ageing skin needs it most. Polynucleotides do not just stimulate active fibroblasts. They call the retired ones back.

The second is UV damage repair. Studying longevity medicine at postgraduate level has deepened my understanding of how photoageing actually works at the molecular level, and this mechanism genuinely surprised me when I first encountered the evidence.

The salvage pathway activated by polynucleotides supports repair of cyclobutane pyrimidine dimers, the specific DNA lesions created by UVB radiation. For patients with years of accumulated sun exposure, polynucleotides are not addressing the surface appearance of that damage. They are intervening at the level where the damage actually lives.

The third is the anti-inflammatory effect. Chronic low-grade inflammation, what longevity scientists now call inflammaging, is one of the primary drivers of accelerated tissue ageing. It degrades collagen, impairs fibroblast function, and creates a cellular environment consistently hostile to repair. Polynucleotides actively suppress the pro-inflammatory cytokines that sustain this process. You are not just treating the skin you have today. You are changing the biological conditions in which that skin will age tomorrow.

How polynucleotides compare to the alternatives

I want to answer this honestly, because not every treatment suits every patient and I have no interest in overstating what polynucleotides do.

Profhilo is a hyaluronic acid bio-remodeller. It works by spreading through tissue planes, hydrating deeply, and stimulating collagen through the mechanical and biochemical effects of high-concentration HA. It addresses hydration, laxity, and a particular quality of superficial skin firmness that polynucleotides do not target in the same way. Polynucleotides target cellular regeneration, UV repair, senescent cell reactivation, and inflammatory modulation. The two treatments work through completely different mechanisms and I frequently recommend both in a phased approach, because the combination addresses aspects of skin ageing that neither handles alone.

Injury-based treatments, radiofrequency, lasers, chemical peels, work by creating controlled damage and harvesting the collagen produced during wound healing. They are effective, particularly for surface resurfacing and pigmentation, and some patients are excellent candidates. The collagen produced is structurally different from what polynucleotides generate. Neither approach is categorically superior. They suit different presentations and different patient priorities.

What polynucleotides offer that nothing else currently does: organised structural collagen produced without injury, senescent cell reactivation, molecular-level UV repair, and an anti-inflammatory effect on the ageing tissue environment. For a patient whose primary concern is skin quality rather than volume, who wants biological regeneration rather than augmentation, and who has the patience to let a cellular process unfold properly, the evidence points clearly in one direction.

What results look like and

when

A patient I treated last year, a woman in her early fifties with significant photoageing and the particular dullness that follows years of sun damage, described her results at her twelve-week review with a phrase that has stayed with me. She said her skin looked like it had remembered something. I thought that was a more precise description of the mechanism than most clinical language manages.

Weeks one to four bring subtle changes: improved texture and hydration as initial fibroblast activity begins. Most patients notice their skin feels different before it looks different. Weeks four to eight bring noticeable firmness and the beginning of fine line smoothing as new collagen integrates into the dermis. By weeks eight to twelve, the remodelling is at peak activity. Skin looks healthier, firmer, and more luminous. Not altered. Restored.

A standard course is two sessions four weeks apart. Maintenance, depending on skin condition and age, is typically one session every six to twelve months.

Are you a canditate?

Polynucleotides suit a wide range of patients and a wide range of concerns, but they are particularly well-matched for early to moderate skin laxity, loss of firmness and fine lines, dull or dehydrated skin lacking vitality, and the visible consequences of photoageing. They work as a standalone treatment and as a regenerative foundation within a broader protocol including Profhilo, microneedling, or red light therapy.

They are not the right choice where the primary concern is significant volume loss or deep structural change. Those presentations need a different conversation, usually involving dermal filler or PDO threads. Part of what I offer at consultation is that honest distinction.

"I have been practising aesthetic medicine long enough to have watched treatments arrive with extraordinary claims and leave without evidence. Polynucleotides have not done that. The A2A receptor mechanism, the senescent fibroblast reactivation, the cyclobutane pyrimidine dimer repair, the anti-inflammatory effect on the inflammaging environment: these are not industry claims. They are documented, replicated mechanisms published in peer-reviewed literature. For someone trained to demand that standard of evidence before accepting anything as real medicine, that matters more than any treatment photograph. In cardiac nursing I learned to trust the science over the sales cycle. Polynucleotides are the treatment that, more than any other in my aesthetic practice, has earned that trust. The biology is real. The results follow the biology. That is how medicine should work."

Marina, Founder of Juvenology Clinic

About Juvenology Clinic

Juvenology Clinic is an aesthetics and longevity-focused clinic based in Maidstone, Kent. It was founded by Nurse Marina, a clinician with 25 years of nursing experience, including six years in cardiac care at KIMS Hospital. The clinic integrates regenerative aesthetic medicine with longevity science, combining clinical precision from critical care with preventive and aesthetic healthcare approaches.

Founder & Clinical Background

Nurse Marina brings a background in acute and cardiac nursing alongside advanced training in longevity and hormonal health. Her qualifications include:

• Executive MSc in Longevity from the Geneva College of Longevity Science

• Healthy Longevity Clinician Programme at the National University of Singapore

• NMC Registered nurse

• Memberships and affiliations including JCCP Verified, BACN Member, ACE Group Registered, Royal College of Nursing, and recognition by the Professional Standards Authority

Clinical Approach

The clinic’s approach blends:

• Regenerative aesthetic medicine

• Evidence-based preventive health strategies

• Longevity science principles

• Anatomically precise, medically informed treatment planning

Book a polynucleotide consultation at Juvenology

References

1. Comparative review of PDRN and PN mechanisms — PMC: pmc.ncbi.nlm.nih.gov/articles/PMC12388916

2. A2A receptor activation, fibroblast response and VEGF upregulation — PMC: pmc.ncbi.nlm.nih.gov/articles/PMC8618295

3. PDRN and cellular senescence mitigation — PLOS ONE: journals.plos.org/plosone/article?id=10.1371/journal.pone.0321005

4. Prospective observational study of polynucleotide injections for periorbital rejuvenation — PMC: ncbi.nlm.nih.gov/pmc/articles/PMC12905022