A recent study featured in the Journal of Cosmetic Dermatology has analyzed the impact of a topical product containing OS-01. This is a senotherapeutic peptide that targets senescence, affecting the skin’s barrier function and multiple aging biomarkers [1].
Conducted by a team from OneSkin alongside academic partners, this initial trial aimed to determine if skin treatment could yield significant results both at the epidermal layer and throughout the body, particularly regarding inflammation and signs of biological aging.
Destroy or modify?
As people age, senescent cells build up in various tissues, such as the skin. These old, damaged cells release persistent inflammatory signals, which harm tissue integrity and function. These inflammatory signals are collectively called the senescence-associated secretory phenotype (SASP).
Senotherapeutics have shown promise in targeting aging cells and improving overall health. These are therapies that target senescent cells, which have stopped dividing and contribute to aging and age-related diseases.
By eliminating or altering these cells to be less harmful, senotherapeutics aim to improve overall health, reduce inflammation, and potentially extend lifespan.
The elimination of these cells using senolytics has emerged as the primary approach in research. A number of companies are actively developing senolytic drugs to remove these potentially harmful cells from the body.
While some researchers initially believed that all senescent cells were a problem and that it would be better to remove them all, the situation appears to be nuanced. Some scientists warn that targeting all senescent cells may result in reduced functions, including impaired wound healing [2].
The late Dr. Judith Campisi, a pioneer in senescent cell research, cautioned that there are many kinds of senescent cells in tissues and that their roles are not fully understood. This is part of why there are ongoing efforts to better understand the different kinds of senescent cells in tissues and what they do.
While interest in senolytics continues apace, some researchers hold that senomorphics, which prevent, modify, or reverse senescence, might be a better approach [3]. OS-01, or Pep 14, can be considered a senomorphic because rather than actively seeking and destroying senescent cells, it instead reduces SASP markers. In other words, it does not kill old, damaged cells; it modifies the harmful signals they secrete.
OS-01 and other senomorphics have previously shown promise in various studies, particularly in relation to skin aging and systemic inflammation. We reported back in 2023 how the OS-01 peptide puts the brakes on cellular senescence.
Anti-inflammatory results
As the skin is the body’s biggest organ, it can potentially generate a large number of senescent cells as it ages. Therefore, these cells’ contribution to whole-body inflammation may be highly significant. Any therapy that can remove them, slow down their accumulation, or modify their signals to be less harmful could have a significant impact on inflammation.
This study appears to suggest that the use of OS-01 correlates with a reduction of systemic inflammatory biomarkers. The data also appears to show an improvement in skin function.
The study looked at cytokines and how they changed following OS-01 treatment. The activity of IL-8, a pro-inflammatory cytokine, was reduced. Interestingly, IL-10, another cytokine that normally has an anti-inflammatory function, was also reduced. The study’s authors suggest that this drop in IL-10, which still remained within its typical range, may be due to a balancing of the wider cytokine landscape.
The researchers reported that TNF-α and IFN-γ both significantly increased in the control group. TNF-α is a master regulator of inflammatory responses and is involved in some age-related and autoimmune diseases. IFN-γ is a cytokine that has many functions, mainly in the immune system. It helps activate macrophages and boosts their ability to eat and kill germs. This cytokine coordinates both innate and adaptive immune responses against viruses, bacteria, and tumors.
The team used mass spectrometry to analyze blood components. They confirmed that the OS-01 peptide was not present in the circulatory system before initial treatment and 12 weeks following application. This confirms that OS-01 remains localized within the skin area where it is administered.
However, even though it was not present in the bloodstream, test group participants showed a reduction in inflammatory markers. This suggests that simply improving the skin’s integrity and function may reduce systemic inflammation. This does make sense given that the skin is the first line of defense for keeping invading pathogens out.
Finally, instrumental evaluations indicated that the OS-01 cohort demonstrated more significant enhancements in skin moisture levels and transepidermal water loss than the control group. Participants also reported that their skin quality had improved, including skin elasticity, hydration, and visual appearance.
An interesting study, but there are issues
Unfortunately, the paper isn’t too specific on the size of the skin area that was treated, so it is hard to understand the scale of the treatment and the quantity of the peptide that was used.
Another issue was that the control group was given another commercial skin product. It would have been useful to have opted for a control group given DMSO or even the OneSkin product with the OS-01 peptide removed. Because they opted to use another skin product, it makes a comparison challenging.
The study group was also quite small. The smaller the study group, the more outliers can skew the results, which may have happened here. The authors have acknowledged some of these limitations, and there is certainly enough evidence to justify further, larger-scale studies.
Finally, and perhaps most obviously, many of the study’s authors have a commercial interest in selling products containing OS-01. OneSkin at the end of the day is a company that needs to sell products and while being directly involved in the research is not a deal breaker, it is something to keep in mind when evaluating the published data.
The skin is an ideal target for testing senotherapeutics due to ease of access and ability to take measurements. Hopefully, we will see more studies using OS-01 or other senolytics or senomorphics in the near future.
Literature
[1] Zonari, A., Brace, L. E., Buhrer, L. B., Harder, N. H., Harker, C., Aronson, A. B., … & Carvalho, J. L. (2025). OS‐01 Peptide Topical Formulation Improves Skin Barrier Function and Reduces Systemic Inflammation Markers: A Pilot 12‐Week Clinical Trial. Journal of Cosmetic Dermatology, 24(4), e70169.
[2] Demaria, M., Ohtani, N., Youssef, S. A., Rodier, F., Toussaint, W., Mitchell, J. R., … & Campisi, J. (2014). An essential role for senescent cells in optimal wound healing through secretion of PDGF-AA. Developmental cell, 31(6), 722-733.
[3] Kim, E. C., & Kim, J. R. (2019). Senotherapeutics: emerging strategy for healthy aging and age-related disease. BMB reports, 52(1), 47.
