Target Cellular Senescence with the Highest Concentration of the OS-01 Peptide

Target Cellular Senescence with the Highest Concentration of the OS-01 Peptide

With just a quick glance, it’s easy to see that the skin around the eyes is fundamentally different from the rest of the skin on your face. Not only is it far thinner than the skin on your cheeks or forehead, it actually ages faster than the rest of your skin, which might be why many of us start to notice under-eye wrinkles as early as our 20s. But what’s happening beyond these surface-level wrinkles? At the cellular level, under-eye skin behaves differently than the rest of your skin –showing accelerated signs of cellular senescence, one of the 9 hallmarks of aging. Join us as we take a closer look at cellular senescence and what it means for the delicate skin around your eyes.









Reference Lab

March 20, 2023


01 What is cellular senescence?

One of the nine hallmarks of aging, cellular senescence is a central driver of skin aging. Derived from the Latin root senex, meaning “old age,” senescence is the end stage in a cell’s life cycle when it stops dividing.

Cells become senescent when they accumulate too much intrinsic and extrinsic damage, driving them into a zombie-like state of dysfunction. Senescent cells secrete harmful biochemical signals, called SASP, that drive the aging process–inducing chronic inflammation, suppressing the immune system, and accelerating aging in neighboring cells. These signals can even inhibit stem cell function, decreasing your tissues’ ability to regenerate.

While cellular senescence is happening constantly in our bodies throughout our lifetimes, it only becomes a problem when our bodies can no longer keep up with the rate of senescence. When we’re young, our immune system can quickly clear away senescent cells, limiting their impact. But as we grow older, our bodies become less efficient at removing senescent cells, leading to key characteristics of aging. ¹

02 Higher cellular senescence in under-eye skin

To understand why the skin around the eyes ages faster than other areas of the face, scientists analyzed the expression of a key senescence marker, CDK2NA, in periocular skin. What they found was that, in both the epidermal and dermal layers, periocular skin expressed significantly higher levels of cellular senescence than other areas of the face. The same study also found that DNA repair pathways were lower in periocular skin, suggesting that DNA repair insufficiency may be an underlying factor in rapid signs of visible aging. ²

03 Reduce cellular senescence with the OS-01 peptide

By reducing cellular senescence, it’s possible to actually reverse biological aging at the cellular level–helping the delicate skin around the eyes stay healthier for longer. So how can you reduce cellular senescence? With OS-01: the first peptide proven to reduce cellular senescence in ex vivo human skin samples (Zonari, et al). In lab studies, the OS-01 peptide has also been shown to reverse the same senescence marker, CDK2NA, in skin cells in vitro, that are particularly affected in periocular skin. Additionally, the OS-01 peptide can reduce a key DNA damage marker, γH2A.x, as shown in lab studies on ex vivo human skin samples. Let’s take a closer look at how the OS-01 peptide works at the cellular level to reduce cellular senescence and support DNA damage repair.

03 The OS-01 peptide significantly reduces key cellular senescence marker, CDK2NA, in ex vivo human skin samples

Remember the cellular senescence marker that scientists studied in periocular skin? OS-01 has been proven to reduce that exact marker–CDKN2A– in ex vivo human skin samples (Zonari, et al). In a lab study conducted by the OneSkin scientific team, the OS-01 peptide reduced CDKN2A in both the dermal and epidermal layers after 5 days of treatment. This shows that the OS-01 peptide could effectively mitigate the natural elevation of cellular senescence in skin, thereby preventing accelerated signs of skin aging.

mRNA expression analysis of ex vivo human skin samples (35, 55, and 79 yr) exposed to the OS-01 peptide (12.5uM) over 5 days, analyzed in the dermis and epidermis (*p<0.05; ****p<0.0001). (Zonari, et al)

04  The OS-01 peptide reduces a key DNA damage marker, γH2A.x, in skin cells in vitro

In addition to higher cellular senescence, scientists found that periocular skin shows decreased DNA repair pathways. To determine whether OS-01 could address this DNA repair insufficiency, our scientists analyzed in vitro skin derived from patients with Hutchinson-Gilford progeria syndrome, a genetic condition that causes premature skin aging with a high level of cellular senescence.

After treating the skin samples with the OS-01 peptide for 48 hrs, they performed a protein expression analysis to see how the peptide would alter protein levels in skin. They found that a key DNA damage marker, γH2A.x, was significantly reduced, indicating the OS-01 peptide’s potential ability to aid in DNA damage repair (Zonari, et al).

Protein expression analysis for γH2A.x in HGPS fibroblasts in vitro treated with 12.5 μM OS-01 peptide for 48 hr (***p<0.001). (Zonari, et al)

05 The OS-01 peptide promotes a reduction in senescent cells in human fibroblast cultures in vitro

To further confirm the OS-01 peptide’s ability to reduce senescent burden in skin, our team took a look at the quantity of senescent cells in skin to determine if the OS-01 peptide effectively reduced their number. Our team treated in vitro fibroblast cultures derived from HGPS patients with senescence-associated beta galactosidase, a compound that selectively stains senescent cells blue, and counted the number of senescent cells before and after treatment with the OS-O1 peptide.

SA B-Gal (senescence-associated beta galactosidase) stained image of HGPS HDFs (human dermal fibroblasts from patient-derived samples with Hutchinson-Gilford progeria syndrome) treated with 50uM OS-01 peptide for 2 days compared to untreated control. (Zonari, et al)

In this study, our scientists found that exposure to the OS-01 peptide promoted the reduction of senescent cells (blue) by up to 50% (Zonari, et al) while maintaining the total number of cells. This means that the OS-01 peptide promoted not just the reduction of senescent cells, but also the renewal of healthier ones.

06 Target senescence with more OS-01 peptide

Formulated with the highest concentration of our OS-01 peptide, our OS-01 EYE Topical Supplement was specifically designed to treat the delicate skin around the eyes. By testing the full formulation of OS-01 EYE on human eyelid skin, we further confirmed OS-01 EYE’s ability to reduce senescent burden in periocular skin. In a lab study, OS-01 EYE was shown to reduce P16, a key marker associated with cellular senescence, in ex vivo human eyelid skin samples.

The results are the average of testing in 3 different ex vivo human eyelid skin samples grown from 42y, 59y, and 84y donors.



Our scientists exposed ex vivo human eyelid skin samples to either nothing (No Treatment) or OS-01 EYE, then performed an expression analysis to evaluate the effect on P16, a marker associated with cellular senescence. We found that OS-01 EYE decreased P16, which means that OS-01 EYE can help mitigate senescence at the molecular level. The result: visible improvements in the skin around your eyes. In tests using OS-01 EYE, over 90% of users saw an improvement in crow’s feet in just 2 weeks. In as little as 4 weeks, a majority of users also saw an improvement in puffiness, sagging, and skin dryness. (Shown in beta tests conducted on 22 randomly selected participants over 4 weeks using OS-01 EYE 2x daily).

07Key Takeaways

  • Periocular skin shows signs of higher cellular senescence than other areas of the face.
  • Cellular senescence is a central driver of skin aging.
  • The OS-01 peptide has been proven to reduce cellular senescence in lab studies on in vitro human skin (Zonari, et al).
  • Formulated with the highest concentration of the OS-01 peptide, our OS-01 EYE Topical Supplement has been shown to decrease P16, a key marker associated with senescence.
  • OS-01 EYE has also been shown to improve crow’s feet, puffiness, and under-eye sagging in a majority of users, based on a 4 week beta study with 22 randomly selected participants using OS-01 EYE 2x daily.
  • References
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