Treating Under-Eye Wrinkles by Waking Up Fibroblasts

When someone asks me which treatment actually helps under-eye wrinkles, my answer rarely starts with a device or a brand name. It starts with a cell: the fibroblast. The skin under the eye is thin and moves constantly, so it shows fatigue in the collagen-producing cells before almost any other part of the face. At our clinic in Gangnam, when I evaluate a patient for under-eye wrinkles, I look first at whether a treatment can get those fibroblasts working again, not just at how much volume it can add.

That is why I reach for polynucleotide (PN) skin boosters more often than other options for this specific area. PN is a DNA fragment extracted from the milt of salmon and similar fish species. Once injected into the dermis, it binds to the adenosine A2A receptor and signals dormant fibroblasts to resume producing collagen and elastin. It is a biological nudge rather than a filling material, which matters in an area where the skin is too thin to tolerate heavy volumizing.

Why I Start With the Fibroblast, Not the Wrinkle

Under-eye wrinkles form differently from wrinkles elsewhere on the face. The skin here is repeatedly folded by blinking and expression, and because it is so thin, the underlying collagen network shows wear earlier. Treating this as a volume problem, by filling the crease, addresses the visible line but not the reason the line keeps reappearing.

Kyung-A Byun and colleagues at Gachon University, in a 2025 study published in the International Journal of Molecular Sciences, examined how polynucleotides act on senescent macrophages and found that PN modulates their cytokine secretion in a way that reduces inflammation, which in turn increases collagen synthesis by nearby fibroblasts. A. Khan and colleagues, in a 2022 review published in the Chinese Journal of Plastic and Reconstructive Surgery, similarly described this class of ingredient as promoting collagen and elastin synthesis while lowering the activity of inflammatory cytokines. Read together, these two papers point to the same conclusion I apply in consultation: for a wrinkle caused by tired connective tissue, restoring fibroblast activity is a more direct target than adding filler volume.

PN Versus PDRN: What the Difference Actually Changes

Patients often ask why we recommend PN specifically rather than the related ingredient PDRN. Both work through the same adenosine A2A receptor pathway, but they differ in molecular weight and chain length. PN carries a larger molecular weight and breaks down more slowly once injected, which is generally understood to give it a longer duration of action compared with PDRN.

I am careful not to overstate the practical difference this makes for comfort during treatment. How much a patient feels during injection depends on the product's concentration, how deep it is placed, and the injector's technique, so it is not accurate to say one ingredient class is simply "less painful" than the other. What I can control, and what I discuss with every patient before treatment, is skin thickness, sensitivity, and any prior procedures in the area, because those three factors determine which concentration and which family of ingredient we design the protocol around.

How We Design the Protocol at Our Clinic

Every under-eye consultation at our Gangnam clinic starts with an assessment before any product is chosen. I check skin condition and try to identify what is actually driving the wrinkle pattern, since not every case has the same underlying cause. After that, we apply a topical anesthetic for about fifteen minutes and inject by hand across the full face rather than isolating the under-eye area alone.

We take this whole-face approach deliberately. Treating the eye area in isolation ignores the fact that skin tone and texture change together across the face, so we address them as one field. For most patients, I recommend a course of three sessions spaced three to four weeks apart before judging the result, since the mechanism is a gradual return of fibroblast activity rather than an instant filling effect.

When a patient also has visible loss of skin firmness, I sometimes combine PN with radiofrequency treatments such as Thermage FLX or OligioX. The controlled thermal injury from these devices creates a healing process that appears to make fibroblasts more responsive during the same window PN is working to reactivate them, so pairing the two can be part of a more complete plan for a patient who has both wrinkling and laxity. If you want a broader sense of how a diagnosis-first process should work before you commit to any Gangnam clinic, our earlier piece on comparing Gangnam skin clinics before you book walks through the questions worth asking.

FAQ

Will I see results from PN skin boosters right away?

No. Because PN works by reactivating fibroblasts rather than filling the area, visible change takes several weeks to appear. I generally ask patients to complete the recommended course of three sessions, spaced three to four weeks apart, before we evaluate the outcome together.

Can PN be used on sensitive or easily flushed skin?

The mechanism described in the research, reduced inflammatory cytokine activity, suggests PN can be well suited to sensitive skin, but individual reactions vary. I always assess the skin in person before treatment to confirm it is the right fit for that patient.

Can I get PN and a lifting treatment on the same day?

It depends on skin thickness and how much recovery capacity the skin has at the time. At our clinic, we decide whether to combine treatments, and in what order, based on the diagnosis from that visit rather than a fixed rule.