What are Polynucleotides? The Science Behind the Salmon Sperm Facial
- Juvenology Clinic
- Oct 1
- 21 min read
Updated: Oct 2
After six years as a cardiac nurse, watching tissue heal, regenerate, do all these remarkable things, I made the leap into aesthetics. And here's what surprised me: the most impressive skin changes I've seen aren't happening on the surface at all. They're happening deep in the cellular machinery, where your body still remembers how to create healthy, youthful skin.
That's what this 10-part series is really about.
We're cutting through the Instagram hype and celebrity endorsements to explore polynucleotides, a regenerative treatment that works with your body's own repair systems rather than simply masking what time has changed.
Yes, people call it the "salmon sperm facial". (We'll tackle that awkward name head-on, I promise.) But what you're actually getting is regenerative medicine that's been safely used for 40 years, now applied to aesthetic concerns.
Over this series, I'll explain what polynucleotides actually are, show you how they work with your cells, walk you through what the research really says, whether they're safe, what results you can genuinely expect, and how to decide if they're right for your skin.
No medical jargon. No hard sells. Just the honest information I wish someone had given me when I first encountered this treatment, from a nurse who brings that same cardiac-care precision to aesthetics.
This is Part 1, where we start with the essentials. Your foundation before we build the complete picture together.
By the end of this part, you'll actually understand what polynucleotides are (and no, it's not fish sperm on your face, though we need to talk about why everyone thinks that), why the science makes sense, and how they differ from every other treatment you've heard about.
Ready? Let's start with the question on everyone's mind: what on earth are polynucleotides, and why would anyone put salmon DNA in their skin?
TABLE OF CONTENTS:
WHAT ARE POLYNUCLEOTIDES?
Polynucleotides are purified DNA fragments derived from salmon or trout sperm that stimulate your skin's natural regeneration processes through cellular bio-stimulation. Unlike dermal fillers that add volume or Botox that relaxes muscles, polynucleotides activate your own fibroblasts to produce collagen, elastin, and hyaluronic acid.
Key Facts:
Clinical efficacy: Studies show 47% increase in collagen production within 23 days
Safety record: 40+ years in medical use with no serious adverse events reported
Treatment type: Injectable regenerative medicine (not a topical facial)
Results timeline: 8-12 weeks for visible improvement, gradual enhancement
Common names: Salmon sperm facial, PDRN treatment, skin bio stimulation therapy
Mechanism: DNA-based cellular signaling, not volume replacement
What it's NOT: Actual fish sperm (extensively purified), a quick fix (requires 3-4 treatments), or a filler alternative (different mechanism entirely)
Current offers at Juvenology Clinic: Polynucleotides 3 for 2: £450 for three areas
Book consultation: https://juvenology-clinic.book.app/book-now
After six years as a cardiac nurse at KIMS Hospital, I thought I understood cellular regeneration. I’d watched hearts heal, tissues repair, and witnessed the body’s remarkable ability to restore itself at a molecular level. Precision mattered. Anatomical knowledge wasn’t optional, it was life-saving.
Then I transitioned to aesthetics, and a patient asked me about Jennifer Aniston’s “salmon sperm facial.”
I’ll admit, I paused. Salmon… what?
But here’s the thing: once I understood the science behind polynucleotides, the treatment everyone’s calling the salmon sperm facial, my cardiac nursing brain got genuinely excited. This isn’t celebrity nonsense. It’s regenerative medicine applied to skin, using the same cellular principles I relied on in critical care.
You’ve probably heard whispers about this treatment. Maybe you saw Kim Kardashian discussing it. Perhaps you read interviews where Jennifer Aniston credits it for her age-defying complexion. Or maybe you’re researching skin rejuvenation treatments that actually work at a cellular level rather than just sitting on the surface.
If you’re wondering what exactly polynucleotides are, how they work, or whether the “salmon sperm facial” is safe, you’re asking the right questions, questions that deserve honest, evidence-based answers from someone who values medical accuracy over marketing hype.
Either way, you’re in the right place.
I’m going to explain what polynucleotides actually are (spoiler: you’re not getting actual salmon sperm on your face), how they’re processed, why the science makes sense from a regenerative medicine perspective, and whether the “salmon sperm facial” name is accurate or misleading.
No medical jargon requiring a degree to understand. No overselling results that sound too good to be true. Just evidence-based information from a nurse who values honest conversations over hard sells.
Let’s get into it.
WHAT POLYNUCLEOTIDES ACTUALLY ARE
Let me start with what polynucleotides aren't. They're not some mysterious celebrity secret or expensive snake oil slathered on your face. And despite what the tabloids call them, you're definitely not getting actual salmon sperm injected anywhere near your skin.
Here's what they actually are: biopolymers composed of nucleotide chains. Think of nucleotides as the building blocks of DNA and RNA, the fundamental molecules that carry genetic instructions for everything your cells do. The "poly" prefix simply means "many". So polynucleotides are long chains
of these DNA building blocks linked together.
Still with me? Good.
In aesthetic medicine, we use polynucleotides as bio-stimulators. Substances that trigger your body's natural regenerative processes rather than adding something foreign to replace what you've lost. They're essentially biological instructions that remind your skin cells how to behave like younger, healthier versions of themselves.
This is DNA-based skin treatment using cellular signaling rather than physical augmentation. Your body already knows how to create youthful skin. It just needs reminding, and sometimes a bit of molecular assistance.
But I know what you're thinking: "If they're so scientifically sound, why haven't I heard about them until celebrities started talking about salmon sperm facials?"
Fair question. Let me explain the whole salmon situation, because this is where it gets interesting and where most confusion happens.
THE SALMON SPERM QUESTION
Here's where the "salmon sperm facial" name comes from, and why it's both technically accurate and deeply misleading.
Polynucleotides used in aesthetic treatments are derived from the sperm cells of salmon or trout. Specifically, from their gonads. Yes, really. Before you get squeamish about this marine-derived skin treatment, let me explain why this makes perfect scientific sense.
Why Salmon or Trout Sperm? The Science
Sperm cells contain exceptionally pure DNA. Unlike other cells in the body, they're designed for one purpose: carrying genetic information. This means:
Minimal cellular debris. No contamination from other cellular components. Just clean, concentrated genetic material.
Freshly produced DNA. Not damaged by aging or environmental stress. These cells are optimized for genetic transmission, which means pristine DNA structure.
High concentration. Packed with the nucleotides needed for treatment formulations at therapeutic levels.
Structural similarity. Fish DNA closely resembles human DNA in molecular architecture. The structure is biocompatible with human cellular systems.
Sustainable source. By-product of the food industry. Salmon already harvested for human consumption provide the raw material, making this an efficient, ethical use of resources.
In my cardiac nursing days, we used porcine heart valves for human transplants because of biological compatibility. Same principle here. Once purified, the source becomes irrelevant. What matters is the molecular structure and cellular communication capability.
The Purification Process: From Fish to Medical-Grade Injectable
This isn't raw fish material being injected into your face. The DNA goes through extensive pharmaceutical-grade processing that transforms it completely:
Step 1: Extraction.
DNA removed from sperm cells through careful chemical processes that isolate nucleic acids.
Step 2: Fragmentation.
Long DNA strands broken into specific chain lengths (typically 50-1,500 kDa molecular weight). This controls how the polynucleotides will behave once injected, their breakdown rate, and how long they'll remain bioactive in tissue.
Step 3: Purification.
Multiple filtration stages remove all proteins, cellular debris, and potential contaminants. This is critical. Proteins cause allergic reactions. Purification removes them completely, leaving only pure DNA fragments.
Step 4: Sterilization.
Medical-grade sterilization ensures no bacterial, viral, or fungal contamination. The same pharmaceutical standards used for any injectable medical product approved for human use.
Step 5: Formulation.
Suspended in sterile physiological solution for injection. The final product is a clear gel that looks similar to other injectables, with no fish-like properties whatsoever.
By the time it reaches your skin, you're receiving highly purified DNA fragments. Molecular building blocks that happen to have originated from fish, but bear no resemblance to anything remotely "fishy."
What You're NOT Getting
Let me be crystal clear about what's not happening with this treatment:
Not actual sperm. The cells are long gone. What remains are extracted, purified, fragmented DNA molecules stripped of all cellular components.
Not fish proteins. Completely removed during purification. This matters enormously for allergy concerns.
Nothing that smells, looks, or feels like fish. The final product is a clear, sterile medical solution indistinguishable from other injectable treatments.
Not random genetic material being injected into your face. Specific polynucleotide chains (PDRN—polydeoxyribonucleotides to be exact) have been proven over 40 years to stimulate tissue repair and cellular regeneration through well-documented mechanisms.
Not topical application. Despite the "facial" name, this is an injectable treatment. The DNA fragments must reach the dermis where fibroblasts live to work effectively.
So yes, technically the "salmon sperm facial" name is accurate in the sense that DNA originates from salmon sperm. But it's about as accurate as calling a heart valve transplant a "pig parts surgery". Medically correct, but missing the sophisticated pharmaceutical processing and science behind the treatment.
I prefer to call it what it is: polynucleotide therapy, bio-stimulation treatment, or regenerative skin injection. Less sensational, more accurate, and it keeps patients from unnecessary anxiety about having fish products on their face.
HOW POLYNUCLEOTIDES DIFFER FROM EVERYTHING ELSE YOU KNOW
If you've explored aesthetic treatments before, you've probably encountered dermal fillers, anti-wrinkle injections (Botox), skin boosters like Profhilo, or various laser therapies. Polynucleotides work differently from all of them, and understanding these distinctions helps clarify what polynucleotides can and can't do for your skin.
They Are NOT Fillers
Dermal fillers add volume and structure using hyaluronic acid or other volumizing substances. They physically fill spaces, lift descended tissue, create contours, restore volume loss from aging.
When injected, fillers stay where placed (though HA fillers spread slightly over weeks). They create immediate, visible structural changes. You see the difference when you leave the clinic—fuller cheeks, smoother nasolabial folds, plumper lips.
Polynucleotides don't add volume. They stimulate your body to improve tissue quality from within through cellular optimization. No structural changes, just enhanced cellular function. You won't look different immediately because nothing is being added or filled.
This is tissue regeneration, not tissue augmentation.
They Are NOT Neurotoxins
Botox and similar anti-wrinkle treatments work by temporarily paralyzing muscles, preventing the movements that create expression lines. The botulinum toxin blocks the nerve signal that tells muscles to contract.
Polynucleotides don't touch your muscles or nerves. They work at the skin cell level, specifically targeting fibroblasts, the cells responsible for producing collagen, elastin, and hyaluronic acid. Completely different mechanism, completely different target tissue.
If you have forehead lines from raising your eyebrows repeatedly, polynucleotides won't address that. Botox will. But if your skin texture and quality have declined independently of muscle movement, polynucleotides address the underlying cellular issue that Botox can't touch.
They Are NOT Traditional Skin Boosters
Products like Profhilo use hyaluronic acid to deeply hydrate and subtly bio-remodel skin. While both Profhilo and polynucleotides fall under the "skin booster" category, their mechanisms differ fundamentally.
Profhilo is primarily about hydration with mild collagen stimulation. You're flooding tissue with moisture-attracting molecules that spread through tissue planes, creating a hydration reservoir.
Polynucleotides are primarily about cellular regeneration with some hydration as a secondary benefit. You're activating repair mechanisms at the DNA level, stimulating fibroblasts to produce more collagen, elastin, and hyaluronic acid naturally.
Both are excellent treatments. Neither is universally "better." They address different underlying issues.
They ARE Bio-Stimulators
This is the key distinction that separates polynucleotides from most aesthetic treatments you've heard about.
Bio-stimulators don't replace anything or block anything. They activate your body's existing repair mechanisms through cellular communication.
Think of them as a wake-up call to dormant systems rather than a substitute for lost substances. It's regenerative aesthetics rather than corrective aesthetics.
When polynucleotides are introduced to your dermis (the deeper layer of skin where fibroblasts live), they essentially communicate with those cells through adenosine receptors: "Remember when you used to produce abundant collagen? When you efficiently repaired DNA damage? When you maintained optimal cellular function? Time to do that again."
Your body already knows how to create youthful skin. It just needs reminding, biological signaling, and sometimes a bit of molecular assistance to reactivate those pathways.
This is why results take 8-12 weeks rather than appearing immediately. You're waiting for your body to respond to the stimulation, produce new collagen, repair cellular damage, and improve tissue quality from within. That biological process takes time.
THE HISTORICAL CONTEXT: NOT ACTUALLY NEW AT ALL
Here's something that might surprise you: polynucleotides aren't a trendy new treatment dreamed up for Instagram influencers in 2023. They've been used in regenerative medicine since the 1980s, over 40 years of clinical application in various medical contexts.
The Medical Origins
Originally, polynucleotide therapy (specifically PDRN—polydeoxyribonucleotides) was developed for wound healing and tissue repair in clinical medicine. Surgeons and wound care specialists noticed that injecting PDRN into damaged tissue accelerated healing, reduced inflammation, and improved tissue quality outcomes.
This wasn't cosmetic. It was reconstructive medicine addressing serious medical needs.
The documented applications included:
Chronic wound management in diabetic patients who struggled with healing due to impaired vascular function and cellular repair mechanisms.
Post-surgical healing enhancement to speed recovery and optimize scar formation, particularly in patients with compromised healing capacity.
Burn recovery support to improve tissue quality after thermal injury, reducing scarring and improving functional outcomes.
Tissue repair after trauma to optimize regeneration in damaged areas where cellular function was compromised.
Vascular insufficiency treatment where poor blood flow impaired healing, using PDRN to stimulate angiogenesis and improve tissue oxygenation.
For decades, polynucleotides were a medical tool documented in peer-reviewed journals, not an aesthetic one featured in beauty magazines.
The Evolution to Aesthetic Applications
In the early 2000s, particularly in South Korea and Italy (both leaders in aesthetic innovation), practitioners started asking an interesting question: "If polynucleotides can heal damaged tissue and stimulate cellular repair in medical wound care, what happens when we use them on aging skin that's experiencing cellular decline?"
The answer was compelling enough that aesthetic-specific versions were developed:
Longer DNA chains for sustained release over weeks. Medical versions used short chains (50-150 kDa) for rapid wound healing action. Aesthetic versions use longer chains (300-1,500 kDa) that break down gradually, providing weeks of cellular stimulation rather than acute wound response.
Different concentrations for various treatment areas based on tolerance and desired outcomes. Under-eyes need gentler formulations (10-15mg/ml) to minimize swelling. Face and neck can handle higher concentrations (18-20mg/ml) for stronger bio-stimulation.
Optimized formulations for dermal injection in healthy skin tissue rather than wound beds requiring acute repair.
Refined protocols for facial aesthetics (multiple treatments over weeks) rather than medical wound care (often single or few applications).
Brands like Rejuran (South Korean pioneer), Plinest/Plenhyage (Italian manufacturers), and more recently Ameela (UK clinics) emerged as the aesthetic applications were refined and commercialized.
The Evidence Base That Matters
This 40-year medical history matters enormously from a safety and efficacy perspective. Unlike treatments that appear with minimal testing and disappear when the next trend emerges, polynucleotides have:
Decades of safety data from medical use in vulnerable populations (diabetics, burn victims, post-surgical patients). We're not experimenting. We're applying proven technology to a new application with well-understood safety parameters.
Peer-reviewed research documenting mechanisms and outcomes. Lee et al.'s 2024 comprehensive review (published in the International Journal of Molecular Sciences, DOI: 10.3390/ijms25158224) found that "polynucleotides have been used to improve skin texture, reduce wrinkle depth, and enhance facial appearance" with "some studies demonstrating significant improvements in skin elasticity and hydration." The science isn't speculative. It's documented.
Established protocols from years of clinical refinement across multiple specialties. We know dosing, frequency, injection technique, expected timelines.
Known risk profiles with extensive patient exposure across diverse populations. Side effects and complications are understood through documentation, not discovered unexpectedly years after market introduction.
When I evaluate new aesthetic treatments, my cardiac nursing training kicks in: Show me the data. How long has this been used?
What does the safety profile look like over time? What are the mechanisms of action?
Are they biologically plausible?
Polynucleotides pass that test comprehensively. They're not experimental. They're not trendy science with five years of existence. They're proven regenerative medicine now being applied to aesthetic concerns. That distinction matters enormously for patient safety and outcome predictability.
WHAT MAKES THEM "NATURAL" (AND WHAT DOESN'T)
I'm cautious about the word "natural" in aesthetics. It's marketing gold but scientifically fuzzy. However, polynucleotides come closer to deserving that label than most aesthetic treatments, with important caveats.
The Natural Element
DNA structure familiarity. Your body recognizes and processes these molecules because they're structurally similar to your own DNA. There's no foreign substance triggering immune rejection or inflammatory cascades.
Existing biological pathways. They work through cellular mechanisms your body already uses (adenosine receptor activation, growth factor release). You're not introducing a foreign process. You're enhancing an existing one through molecular signaling.
No synthetic substances. Once purified, they're just nucleotide chains—the building blocks that exist in every cell of your body, not manufactured chemical compounds.
Biocompatible molecules. Minimal risk of rejection or allergic reaction because your body doesn't identify them as foreign invaders requiring immune response.
Completely biodegradable. Broken down by natural enzymatic processes and absorbed by the body. Nothing remains permanently in tissue. No accumulation over repeated treatments.
The Not-So-Natural Element
External source. Yes, they come from fish. But so do many supplements (omega-3s, collagen) we consume without concern about "naturalness."
Extensively processed product. Pharmaceutical-grade purification and formulation. Nothing "straight from nature" about the manufacturing process, even if the source is natural.
Injectable delivery. Nothing natural about needles penetrating your dermis. This is a medical intervention requiring technique and expertise.
Controlled chain length. Manufactured to specific molecular weight specifications for optimal cellular interaction, not naturally occurring in this exact form.
My perspective? Calling them "natural" matters less than understanding they work with your body's existing biology rather than against it or introducing completely foreign mechanisms.
They don't disrupt normal cellular function. They don't introduce synthetic materials that sit inert in your tissue forever. They stimulate biological processes, then degrade naturally, leaving behind the beneficial results of that temporary stimulation.
That's regenerative medicine. That's how your body heals itself with a bit of molecular assistance and biological nudging.
THE CLINICAL EVIDENCE: WHAT RESEARCH ACTUALLY SHOWS
While I'll cover mechanisms in depth in Part 2, here's what peer-reviewed studies document about polynucleotide efficacy. This isn't marketing fluff. This is published, peer-reviewed research.
Collagen Production Increases
Clinical studies document impressive collagen stimulation. Research shows polynucleotides can increase collagen production by up to 47% within 23 days and help create a thicker, healthier epidermis with improvements of 52% in the same timeframe.
These aren't marketing claims from manufacturers. They're measurable, documented cellular changes verified through histological analysis.
DNA Repair Mechanisms
Lee et al.'s 2024 review (International Journal of Molecular Sciences) documented a particularly fascinating finding: "PDRN promoted cyclobutene pyrimidine dimer (CPD) repair in UVB-exposed dermal fibroblasts."
In plain English? Polynucleotides help repair the specific DNA damage caused by sun exposure. CPDs are the primary DNA lesions created by UV radiation that lead to mutations, cellular dysfunction, and skin aging. The ability to enhance repair of this specific damage is significant for photoaging treatment.
Pigmentation Improvement
Research published in the Journal of Cosmetic Dermatology found that "PDRN significantly inhibits melanin synthesis by suppressing melanogenesis via the inhibition of melanogenic gene expression and tyrosinase enzymatic activity."
This contributes to more even skin tone over time, particularly beneficial for post-inflammatory hyperpigmentation or sun-induced pigmentation irregularities.
Angiogenesis and Tissue Repair
Studies document that PDRN promotes angiogenesis, cellular activity, collagen synthesis, soft tissue regeneration, and skin priming and revitalization. This multi-mechanism action explains why polynucleotides show benefits across various skin concerns rather than addressing only one specific issue.
Safety Profile Documentation
Lee et al.'s comprehensive 2024 review analyzing multiple clinical studies found: "In all of the above studies, there were no serious adverse events reported."
That's remarkable for any injectable treatment. The safety profile over 40 years of medical use across thousands of patients is extraordinarily clean.
Long-Term Efficacy
A 2007 clinical trial following 143 patients found significant skin elasticity and hydration improvements maintained for 6 months post-treatment. The 2020 expert consensus report by Cavallini et al. (Journal of Cosmetic Dermatology, DOI: 10.1111/jocd.13679) confirmed long-term skin quality improvements, especially in cheeks, perioral region, and neck with proper maintenance protocols.
Important Caveats (Being Honest About Research Limitations)
Lee et al. emphasize important context: "There were varying degrees of efficacy and safety" across studies, and much of the evidence comes from observational studies rather than large randomized controlled trials.
They note "heterogeneity across protocols, populations, and outcome measures," which complicates direct comparisons. Additionally, "uncertainty around the optimal dosing, administration methods, and long-term effects" remains.
My interpretation as a nurse? The consistency of safety data and efficacy signals across decades of use in multiple applications provides solid evidence for clinical use. We're not dealing with experimental science. But more rigorous studies would strengthen the evidence base, particularly for aesthetic-specific applications.
The research supports what I see clinically: meaningful skin quality improvements with an exceptionally clean safety profile. That's enough for me to recommend polynucleotides confidently to appropriate candidates.
THE SCIENCE BEHIND THE NAMES: PDRN VS PN AND BRAND CONFUSION
If you research polynucleotides, you'll encounter confusing terminology that makes comparing products difficult. Let me clarify the landscape so you understand what practitioners are actually discussing.
PDRN vs. PN: What's the Difference?
PDRN (Polydeoxyribonucleotide) refers to DNA-only fragments, typically shorter chains (50-150 kDa molecular weight), historically used in medical wound healing applications where rapid cellular response was needed.
PN (Polynucleotide) is a broader term encompassing both DNA and RNA fragments, typically longer chains (300-1,500 kDa) used in aesthetic applications where sustained release and prolonged bio-stimulation are desired.
Some practitioners and manufacturers use these terms interchangeably, which creates confusion. Technically, most aesthetic products now use longer-chain polynucleotides (PN) rather than the shorter medical-grade PDRN, though the cellular mechanisms are fundamentally similar—both work through adenosine receptor activation and growth factor signaling.
Brand Names You'll Encounter in UK Clinics
Ameela. Currently the most popular in UK practices, known for longest chain length (1,500 kDa) for sustained bio-stimulation. This is what we use at Juvenology Clinic due to its evidence-based formulation.
Nucleofill/Nucleadyn. Earlier aesthetic brands. Nucleadyn was actually rebranded as Ameela, so if you've read about Nucleadyn and wonder where it went, it's now marketed under the Ameela name.
Plinest/Plenhyage. Italian brand from Mastelli, offers the highest concentration options available (20mg/ml). Some practitioners prefer this for more dramatic bio-stimulation, though it comes with more swelling.
PhilArt by Croma. Newer formulation gaining traction in UK market, competitively priced.
VITARAN. Unique because it's trout-derived rather than salmon, marketed specifically for delicate under-eye treatments with lower concentration (10mg/ml).
Rejuran. The South Korean original that popularized the "salmon sperm facial" term internationally through celebrity endorsements and Asian beauty trends.
Does Brand Actually Matter for Results?
Somewhat, but less than you might think. The key differences are:
Chain length. Longer generally means longer-lasting results because the enzymatic breakdown process takes more time, providing sustained cellular stimulation over weeks.
Concentration. Higher concentration (20mg/ml) means more intense bio-stimulation but also more temporary swelling and discomfort initially. Lower concentration (10-15mg/ml) means gentler experience but possibly requires more treatments.
Purity standards. All CE-marked products meet European safety standards, so the quality baseline is consistent across reputable brands.
Specific formulations. Some brands have variations designed for eyes, scalp, body, or face specifically, optimizing viscosity and concentration for different tissue characteristics.
In my practice at Juvenology Clinic, I use products from established European manufacturers with rigorous quality control and CE marking. Brand matters less than proper injection technique, appropriate product selection for the treatment area, and practitioner expertise in layering and depth.
What I won't do is claim one brand is categorically "better" than others in all circumstances. They're tools with different specifications. The skill lies in matching the right tool to the patient's needs, tolerance, and goals.
WHAT ACTUALLY GOES INTO YOUR SKIN
When I prepare a polynucleotide treatment, here's what I'm working with in clinical practice:
The Product Appearance
A clear, slightly viscous gel in a sterile syringe. It looks similar to hyaluronic acid fillers at first glance but feels different when injected, less thick and cohesive, more fluid and spreadable through tissue planes.
Depending on the brand and concentration, one syringe typically contains:
2ml of solution. Standard volume for most facial aesthetic treatments, though some eye-specific products come in 1ml syringes.
Polynucleotides at concentrations ranging from 10mg/ml (gentle, used for under-eyes) to 20mg/ml (stronger bio-stimulation for face and body). Higher concentration delivers stronger cellular activation but more temporary swelling as a trade-off.
Sterile physiological solution as the carrier. Usually sterile water or saline. Simple, biocompatible base without additional additives.
Minimal additives. Unlike hyaluronic fillers, no lidocaine typically included in the formulation. Some practitioners apply numbing cream pre-treatment, or use dental blocks for more sensitive patients.
The Molecular Composition
Polynucleotides consist of nucleotide chains with specific molecular weights carefully controlled during manufacturing. Generally between 50 and 1,500 kDa (kilodaltons) depending on whether it's shorter PDRN or longer-chain aesthetic PN.
The longer chains (like Ameela at 1,500 kDa) provide sustained release over 4-6 weeks. The shorter chains act more rapidly but are metabolized faster. Different applications benefit from different chain lengths based on desired timeline.
What Happens When Injected
Once introduced to your dermis through multiple microinjection points:
The polynucleotide solution disperses through the tissue matrix
Natural enzymes (DNases) begin breaking down the long chains into smaller fragments
These fragments (eventually becoming mononucleotides, single building blocks) bind to adenosine receptors on fibroblast cell membranes
Cellular activation begins immediately at the receptor level, though visible results take weeks
Over 4-8 weeks, the accumulated bio-stimulation effect manifests as increased collagen, elastin, and hyaluronic acid production
All polynucleotide material is fully absorbed and metabolized by 6-8 weeks
Nothing remains permanently. No foreign substance sitting in your dermis like filler. No accumulation over repeated treatments. Just the beneficial results of temporary cellular activation that prompted your body to improve tissue quality naturally.
This is fundamentally different from fillers (which remain as intact molecules for 6-18 months) or permanent implants. Polynucleotides do their job through biological signaling and disappear completely through natural metabolic processes.
WHY POLYNUCLEOTIDES ARE SAFE
Given my cardiac nursing background, I'm acutely aware of tissue rejection risks. When introducing anything foreign to the body, the immune system evaluates constantly: friend or foe?
Polynucleotides typically register as "friend" for several biological reasons.
Structural Familiarity at Molecular Level
DNA structure is universally recognized by cells across all species. Your body doesn't see polynucleotides as invaders because the molecular architecture, the double helix structure, the nucleotide base pairs, the sugar-phosphate backbone is identical to what exists in every cell you have.
Your immune system evolved to recognize foreign proteins, cellular membranes with different surface markers, and pathogens with distinctive molecular patterns. Pure DNA fragments don't trigger these recognition pathways because DNA itself is a fundamental molecule your body produces constantly.
No Protein Content to Trigger Allergies
Proteins trigger the vast majority of allergic reactions. When people have fish allergies, they're reacting to specific fish proteins (primarily parvalbumin). Fish proteins could theoretically cause problems for people with true fish allergies.
But pharmaceutical-grade purification removes proteins completely. What remains are pure nucleotide chains, DNA building blocks without the cellular components that trigger immune responses.
Your immune system has nothing to react against because there's nothing "foreign" in the immunological sense about purified DNA fragments devoid of protein content.
No Cellular Components
No fish cells. No cellular membranes with foreign surface markers. No organelles. No mitochondria. Just molecular building blocks that could have come from any species because DNA structure is remarkably conserved across evolution.
Your immune system recognizes threats at the cellular and protein level. Individual DNA molecules divorced from their cellular context don't register as threatening.
Biocompatible Molecules Your Body Uses Daily
When polynucleotides are broken down by DNase enzymes into mononucleotides (adenine, guanine, cytosine, thymine), they're chemically indistinguishable from the nucleotides your cells produce naturally every moment for DNA replication, RNA synthesis, and cellular energy (ATP).
Your body is already processing millions of nucleotides daily. Adding purified exogenous nucleotides doesn't introduce anything foreign to your metabolic pathways.
The Rare Exceptions
True allergic reactions to properly purified polynucleotides are extraordinarily uncommon. Clinical trials report essentially zero incidence of allergic responses.
However, we need to discuss potential concerns transparently:
Severe fish protein anaphylaxis. If you have life-threatening anaphylactic reactions to fish consumption (throat swelling, breathing difficulty, cardiovascular collapse), we should discuss this thoroughly during consultation. Though purification removes proteins, I understand if you prefer avoiding anything fish-derived for psychological comfort or extreme caution.
Shellfish allergy. NOT a contraindication. This is critical to understand. Completely different proteins. Shellfish allergies involve tropomyosin and other crustacean-specific proteins. Fish proteins are different molecules entirely, and polynucleotides contain neither shellfish nor fish proteins after purification.
General seafood sensitivity. Usually fine, but patch testing is available for cautious patients who want additional reassurance before proceeding with full treatment.
In my years treating patients at Juvenology Clinic, including many with various food allergies, I've never witnessed an allergic reaction to properly purified, CE-marked polynucleotides. The safety profile is remarkably clean.
QUICK COMPARISON: POLYNUCLEOTIDES VS OTHER INJECTABLE TREATMENTS
Treatment Type | Primary Function | Mechanism | Results Timeline | Duration | Best For |
Polynucleotides | Cellular regeneration | Bio-stimulation through DNA signaling | 8-12 weeks gradual | 6-9 months with maintenance | Skin quality, texture, cellular health, UV damage repair |
Dermal Fillers (HA) | Volume replacement | Physical filling with gel | Immediate | 6-18 months | Structural loss, contours, volume restoration, lips |
Botox / Dysport | Muscle relaxation | Neurotoxin blocking nerve signals | 3-7 days | 3-4 months | Expression lines, wrinkle prevention, muscle-related lines |
Profhilo | Hydration + bio-remodeling | HA spreading + mild stimulation | 2-3 weeks | 6-9 months | Dehydration, quick radiance boost, skin laxity |
Skinboosters (HA) | Deep moisturizing | Hydration reservoir | 1-2 weeks | 3-6 months | Surface hydration, glow, dehydrated skin |
Sculptra | Collagen stimulation | PLLA particle irritation | 3-6 months gradual | 18-24 months | Volume loss, facial contouring, structural support |
Key Takeaway: Polynucleotides address the underlying cellular dysfunction and DNA damage that other treatments don't touch. They're complementary, not replacements for other injectables. Many patients benefit from strategic combinations.
We'll compare these treatments in exhaustive detail in Part 4 of this series, including when to choose each treatment and how to combine them effectively.
COMMON QUESTIONS ABOUT POLYNUCLEOTIDES
Is the salmon sperm facial really salmon sperm?
Technically yes, the DNA originates from salmon or trout sperm cells. But it's extensively purified through pharmaceutical-grade processing. The DNA is extracted, fragmented to specific chain lengths, stripped of all proteins and cellular material, sterilized, and formulated into medical-grade injectable solution. What's injected is purified DNA fragments, not fish sperm cells or fish material. By the time it reaches your skin, it's molecular building blocks that happen to have originated from fish but bear no resemblance to anything "fishy."
Are polynucleotides safe for long-term use?
Yes, with an exceptional safety record. Polynucleotides have been used in regenerative medicine for 40+ years. Clinical studies report no serious adverse events. The treatment is completely biodegradable, nothing remains permanently in tissue. Each treatment is fully metabolized within 6-8 weeks, so there's no accumulation. Temporary swelling and minor bruising are the most common side effects.
How are polynucleotides different from dermal fillers?
Completely different mechanisms and purposes. Fillers add volume physically using hyaluronic acid gel that sits in tissue. Results are immediate and structural. Polynucleotides stimulate your own collagen production through cellular signaling, nothing is added structurally. Results take 8-12 weeks and focus on tissue quality rather than volume. Fillers address "I've lost volume and need it replaced." Polynucleotides address "My skin quality has declined and needs cellular optimization." Different tools for different concerns.
Do I have to worry about fish allergies?
Shellfish allergies are NOT a contraindication, these are completely different proteins. True fish protein allergies are rare, and the purification process removes all proteins from the final product. What remains are pure DNA fragments without the proteins that cause allergic reactions. However, if you have severe anaphylactic fish allergy, discuss this during consultation. Patch testing is available for cautious patients. In my clinical experience treating hundreds of patients, including many with food allergies, I've never witnessed an allergic reaction to properly purified polynucleotides.
How much do polynucleotides cost in the UK?
UK pricing ranges from £199 to £1,200+ per treatment depending on location (London premium vs regional pricing), practitioner expertise, brand used, and area treated. A typical full facial treatment at mid-range clinics costs £350-£450. Under-eyes alone are typically £300-£600. You need 3-4 treatments initially (spaced 3-4 weeks apart), then maintenance every 6-9 months.
At Juvenology Clinic, our current offer is Polynucleotides 3 for 2: £450 for three treatment areas.
How long until I see results from polynucleotides?
This is cellular regeneration, not instant transformation. The timeline is gradual: immediate swelling for 24-48 hours, then nothing visible for 3-4 weeks while cellular activation occurs. Visible results typically appear 8-12 weeks after starting treatment, peaking about one month after completing your full course. This isn't a quick fix, it's biological regeneration that requires patience.
Can I combine polynucleotides with other treatments?
Yes, and strategic combinations often deliver superior results. Polynucleotides work beautifully with Profhilo (complementary hydration + regeneration), before fillers (extends filler longevity by up to 40%), with RF microneedling (synergistic collagen production), and alongside Botox (different mechanisms don't interfere). The key is proper timing and sequencing. Some combinations should be done simultaneously, others require spacing.
KEY TAKEAWAYS
What You've Learned About Polynucleotides:
✓ Polynucleotides are purified DNA fragments derived from salmon/trout sperm, not actual fish sperm. Pharmaceutical-grade processing removes all cellular material and proteins.
✓ They've been used in regenerative medicine for 40+ years in wound healing before aesthetic applications, establishing a strong safety record with no serious adverse events documented in clinical studies.
✓ They work as bio-stimulators that activate cellular repair mechanisms through DNA signaling rather than replacing lost substances. This is regenerative medicine, not volume replacement.
✓ Fundamentally different from fillers, toxins, and traditional skin boosters in both mechanism and purpose. Understanding these distinctions is crucial for realistic expectations and treatment selection.
✓ Exceptionally safe due to high biocompatibility. Your body recognizes DNA structure as familiar molecular building blocks, minimizing rejection risk. All material is biodegradable and fully metabolized.
✓ Multiple reputable brands exist with variations in chain length (50-1,500 kDa) and concentration (10-20mg/ml). All CE-marked brands meet European safety standards. Brand matters less than technique.
✓ The "salmon sperm facial" name is technically accurate but misleading. You're receiving purified molecular building blocks used in cellular signaling, not fish material. More accurately called polynucleotide therapy or bio-stimulation treatment.
✓ Clinical evidence shows 47% collagen increase within 23 days, DNA damage repair, melanin synthesis inhibition, and sustained results for 6+ months with maintenance protocols.
✓ Results are gradual (8-12 weeks), not immediate. This is biological regeneration requiring patience. Three to four treatments needed for visible improvement, then maintenance every 6-9 months.
✓ Shellfish allergies are NOT a contraindication (different proteins entirely). True fish allergies rarely problematic after purification removes all proteins, but discuss severe allergies during consultation.
Now you understand what polynucleotides are, their medical history, and why they're not as strange as "salmon sperm facial" suggests. But how do these DNA fragments actually communicate with your skin cells to produce collagen?
Part 2 explores the fascinating cellular mechanism:
How polynucleotides trigger fibroblasts to increase collagen production by 47%
The adenosine receptor pathway that activates cellular regeneration
Why senescent (dormant) fibroblasts reactivate after polynucleotide treatment
DNA repair mechanisms for UV-damaged cells
Anti-inflammatory and antioxidant effects at the molecular level
What the peer-reviewed research actually shows (and doesn't show)
Why results take 8-12 weeks from a biological perspective
We'll dive into the cellular biology explained clearly without intimidating technical jargon, review the clinical evidence with proper context, and discuss what polynucleotides can and can't do for your skin from a mechanistic standpoint.
READY TO EXPLORE POLYNUCLEOTIDES FOR YOUR SKIN?
After reading Part 1, you understand the science behind this treatment and why it's gaining attention in evidence-based aesthetic medicine. If you're interested in learning whether polynucleotides suit your specific skin concerns:
Book a consultation at Juvenology Clinic, 82 King Street, Maidstone, Kent.
Current Treatment Offers:
Polynucleotides 3 for 2: Three treatment areas for the price of two - £450 total (save £225)
Lumi Eyes 3 for 2: Buy 2 treatments, get 1 free - £300 total (save £150)
Location & Accessibility:
Easily accessible from London (30-40 minutes by train from various London stations)
Free parking available nearby
Flexible appointment times including evenings
Book Consultation: https://juvenology-clinic.book.app/book-now
ABOUT THE AUTHOR
Nurse Marina is an aesthetic nurse specialist with 8 years of experience leading Juvenology Clinic in Maidstone, Kent. Her background includes 6 years as a cardiac nurse at KIMS Hospital (where she developed expertise in vascular anatomy and precision injection technique) and 2 years as an aesthetic nurse specialist at Spencer Private Hospitals.
She holds NMC registration and is a member of BACN (British Association of Cosmetic Nurses), JCCP (Joint Council for Cosmetic Practitioners), ACE Group, and the Royal College of Nursing. She's also registered with the ICO (Information Commissioner's Office) and verified by the Professional Standards Authority.
Her approach combines rigorous medical expertise with warm, maternal care—bringing cardiac nursing precision and anatomical knowledge to aesthetic practice. She's passionate about evidence-based treatments over trend-chasing, patient education over sales pressure, and honest conversations about realistic outcomes.