Senior researcher Yu Su-ji majored in biotechnology during her undergraduate years and mainly studied membrane protein in graduate school. She earned her master's degree in cell focused research, such as identifying by which mechanism the protein complex in the endometrium of mitochondria recognizes and sends numerous proteins back to place. She joined LG Household & Health Care as her first job in 2018 and is currently conducting human testing research at a research organization that develops efficacy. She is in charge of measuring various characteristics of actual skin and evaluating skin improvement by cosmetics.
Kim Mi-rim, a senior researcher at the institute, majored in life sciences in both academic and master's courses, and studied the mechanisms, which are diseases of allergic diseases such as asthma and atopy, in the laboratory of allergic immunology. In particular, she studied how allergic diseases caused by extracellular vesicles (EVs), a morbid substance produced by microorganisms, are induced and how immune responses appear. She joined LG Household & Health Care in 2011 and have been focusing on efficacy research for 10 years. The school mainly conducted animal testing, but the company is conducting research focusing on various cell experiments that can replace animal testing. She is currently conducting research on finding effective materials to identify causes of aging of human body and skin and to help alleviate or improve the status quo.
‘Oxygen’. Oxygen is an essential element for the survival of living things, and in most cases it is an element with a positive image. However, under the theme of "skin health," negative images are stronger because there is a strong perception that "active oxygen" caused by cell breathing is the main culprit of cell damage and skin aging. This is why most anti-aging functional cosmetics have 'anti-oxidation' as a key effective point.
Among them, a study focused on the role of "good oxygen" on the skin, not on "bad oxygen." The paper is titled "Relationship of Transcurious Oxygen Tension with age and skin elastability in Korean women," which was published in a joint study by Yu Su-ji, a senior researcher at LG Household & Health Care, and Kim Mi-rim, a senior researcher at the institute. This paper is an online published paper published in November 2019 in the international journal “Skin Research and Technology”, which analyzes skin characteristics according to people's age group and reveals that "cystic oxygen tension" has a significant correlation with each skin characteristic. This paper met the two researchers and heard firsthand how they started their research from this perspective and how they were able to derive their findings. (They wore masks during the interview and took pictures outdoors due to COVID-19.)
The subject of research is interesting. Usually, in cosmetic research, oxygen has a negative image that causes skin aging, but in contrast, how did you set oxygen as the target material for improving skin aging?
Mirim: We have noted that the oxygen that affects the skin has some negative effects, such as active oxygen that promotes skin aging, but on the contrary, some have good effects such as skin regeneration. The active oxygen in cosmetic research is a chemically reactive form of oxygen that is produced inside our bodies, which can damage cells by taking electrons away from other molecules around us and activating protease. In particular, the skin exposed to ultraviolet rays, stress, and other environmental pollutants will increase the number of these free radicals, causing damage cells to proliferate, which will soon become "aging."
But if the free radicals produced in the body are bad oxygen that has a negative effect on the human body, the other oxygen present in the body is not only vital to life but also positive for skin regeneration. This view is mainly in the medical field, and we often see the use of techniques that speed healing by injecting high concentrations of oxygen after surgical procedures. The role of good oxygen is the same for the skin. The basis of skin regeneration is cell division. It's a process in which old cells are replaced by new cells through the synthesis of extracellular components. At this point, he thought that higher concentrations of transcutaneous oxygen would help improve aging skin as the metabolism of skin cells would be activated.
You must have been referring to a lot of medical research.
Mirim: That's right. Assuming that there will be many reliable research results since oxygen-based procedures are a medical treatment method, we found that high-pressure oxygen treatment has a positive effect on skin regeneration and collagen promotion. However, since it was not a topic that was mainly addressed in the field of cosmetic research (the skin regeneration/healing effect is a medical treatment effect and not a cosmetic efficacy area), few studies have been conducted regarding skin aging specific to the facial area. We focused on this part and analyzed the role of oxygen as the target material for skin aging care as a prior study to implement oxygen effects in Facial-care cosmetics.
Have you ever released any oxygen-based cosmetics before?
Mirim: In fact, there has been an effort in the past to improve skin using oxygen. In fact, between 2011 and 2012, many products such as oxygen masks and cleansers were released and became an issue. Because these products had the concept of oxygen water or oxygen directly in the product, there was a problem that oxygen could not be maintained for a long time, and it was difficult to show sincere effects because empirical research on the amount of oxygen in the skin was not supported. In other words, by putting oxygen in the formulation and supplying it to the surface of the skin, there was a limit to improving aging in the skin. I thought that to solve the fundamental problem of oxygen-applied cosmetics, a basic study was needed to confirm the link between changes in oxygen volume (capsular oxygen tension, TcPO2) on the skin and skin aging. To that end, we're working with Yoo Soo-ji, a senior researcher in charge of human testing research in our research.
Please explain the concept of Transcutaneous oxygen tension, TcPO2.
Mirim: TcPO2 is 'Transcutaneous Oxygen Pressure' and can be understood as a Skin Oxygen Tension in the skin. The measurement sensor is mounted on the skin and heated to measure non-invasive oxygen in the skin through the transcutaneous. Simply put, the amount of oxygen that can be supplied to the skin.
Please introduce the research.
Suji: In this study, we focused on correlating transcutaneous oxygen tension with various biophysical skin indicators, especially skin aging. We measured the elasticity, moisturization, sebum, skin brightness, redness, blood flow, and transcutaneous oxygen tension within certain conditions for female subjects of various ages (20 to 60s).
First of all, we analyzed the correlation between skin characteristics and age, similar to previous studies, and we found that as you get older, the elasticity decreases, the skin color darkens, and the sebum decreases. And as I got older, I could see that the tension of the transcutaneous oxygen decreased. In Table 1, 'r' is a 'Pearson correlation coefficient', which indicates that the higher the absolute value, the higher the correlation, and the positive/negative correlation direction depending on the sign. If you look at the correlation between transcutaneous oxygen tension and other skin properties, you can see that the higher the transcutaneous oxygen tension, the greater the elasticity of the skin (Table 2). Now, if you infer from these two experiments, you can see that as you get older, your transcutaneous oxygen tension decreases, which leads to skin aging, such as decreased skin elasticity.
Were there any similar studies? Please explain the differences in this study.
Suji: There was a similar study published in China, the same Asian country, about a year before our team. In this study, we found a positive correlation between transcutaneous oxygen tension and skin elasticity. The devices used for measurement were different, but similar results were found for the relationship between transcutaneous oxygen and skin elasticity. However, unlike our research, the Chinese research team's research focused on skin elasticity and wrinkles for subjects of limited age (36-49 years old), who are already aging. If Chinese studies are static studies that analyze the relationship between the two parameters of skin characteristics and indicators, we have conducted a complex and dynamic study of subjects in their 20s and 60s by linking age-specific skin changes and biophysical indicators called transcutaneous oxygen tension.
In the meantime, we have been able to find that oxygen, which is known to have a negative impact on skin aging, can serve as an improvement point for skin elasticity degradation caused by aging. It is a study that proved the vague illusion of oxygen, which existed only as an image of a woman like oxygen in the past, as an objective indicator.
Was there anything difficult in the research?
Suji: in fact, the transcutaneous oxygen tension was an unfamiliar concept to us. It's a concept that was mainly used in the medical field, so all of the experimental devices were medical devices. Of course, it wasn't used in our lab, not in the medical institution, and we had to buy a new device for this research and learn how to use it. There were a lot of trials and errors from the beginning of the study because I used the device for the first time.
The medical device we used, for example, was used to measure the skin of the necrotized arms and legs, but when we measured the skin on the face, it was very difficult because it had a different structure from the arms and legs, and there was no fixed measurement area. So I asked the researchers from the same team for help, and I had to test every single part of the face to see if the skin could be measured well. Because of this, it took about four months to set up the device. And every time you measure it with the device.
The cost of disposable consumables was so high that I remember proceeding more carefully. (laughs)
What would you expect?
Suji: We have identified the possibility of improving skin aging through transcutaneous oxygen control, and I think the biggest achievement is that it has served as a foundation for developing new concepts of products. By identifying the relationship between transcutaneous oxygen tension in the skin and skin aging, we've come up with a new paradigm for improving aging by making sure that the skin has full access to the oxygen it needs, unlike the conventional way of putting oxygen directly into the formulation and applying it to the skin surface. Although not introduced in this paper, we studied and applied the components that can improve the transcutaneous oxygen tension inside the lab. Through the human evaluation with the developed product, we were able to confirm that it has the effect of increasing skin elasticity. The product developed and released in this way is the new ‘Sum37 New Secret Essence’ renewed this year. This product is one of the representative products of our Sum37 brand and is introduced as a product that boosts the oxygen tension of the skin, and I heard that it is well received not only by domestic but also by overseas consumers. We feel the most rewarding when our basic research results are applied to the actual product and introduced to our customers.
There seems to have been more follow-up research since then. Can you introduce them?
Mirim: This paper was approved last November, and since then, we have selected transcutaneous oxygen tension as the main target for skin aging improvement and conducted further research on improvement measures and mechanisms. We've experimented with the effects of oxygen on aging from the perspective of skin cells, and we're still working on key factors that affect the amount of oxygen in the skin. In the process, we were able to develop components that improve the tension of the transcutaneous oxygen, and we're also preparing a follow-up paper. I hope to be able to reveal this in a good journal sooner or later.
Please tell me your future plans or aspirations.
Mirim: The more I study aging, the more I think I'm not familiar with it. It's already been 10 years since I've studied skin aging and efficacy, and I want to be an expert who can confidently explain skin aging anywhere. I’ll need more effort and study than I do now. I also want to contribute to the development of good products that customers can feel based on my research.
Suji: From the first year of my career, I had a valuable experience working with amazing senior on an interesting topic. As we proceed with this study, we will find new topics related to aging and skin on our own and take the initiative in various studies. Next time, I'd like to suggest to Mirim to do research together with my idea. I also look forward to hearing from junior researchers to work with me. (laugh)