Role of Ceramide and Its Metabolites in the Regulation of Epidermal Barrier Function

( Sekyoo Jeong ),( Kyong-oh Shin ),( Kyungho Park ) 한국피부장벽학회 2018 한국피부장벽학회지 Vol.20 No.1

Ceramide is a main epidermal lipid and is composed of long-chain aminoalcohol and amide-linked fatty acids, whose chain lengths are 16-20 and 16-36, respectively. Emerging evidences demonstrated that ceramide plays a primary structural role in forming epidermal permeability barrier. In addition, ceramide and its metabolites, including sphingosine-1-phosphate, serve as signaling lipid to modulate multiple cellular functions, e.g., proliferation, differentiation, and apoptosis, as well as epidermal antimicrobial barrier. Here, we describe the signaling roles and current knowledge of ceramide and its metabolites in the regulation of epidermal barrier function.

Development of Sphingolipid Mimetics for Cosmetic Application

Sekyoo JEonG 한국생물공학회 2017 한국생물공학회 학술대회 Vol.2017 No.4

Dermatologic Application of Autophagy Regulator

( Sekyoo Jeong ),( Keedon Park ) 한국피부장벽학회 2017 한국피부장벽학회지 Vol.19 No.2

Autophagy can be defined as a self-digestive process, targeting internal or damaged organelles and misfolded proteins to lysosomal degradation. While its major role is a survival mechanism under stress conditions, such as nutrient restriction, it can also induce cell death under certain conditions. Changes in cellular energy status or inhibition of mTOR(mammalian target of rapamycin) are well-known activating signals of autophagy. In addition, sphingolipids metabolites, including sphingosine-1-phosphate and dihydroceramides, are also known to modulate the autophagy responses in various cells. Recently, increased attentions have been paid to the roles of autophagy process in skin(patho)physiology. Along with the potential involvement of autophagy in differentiation of epidermal keratinocytes, several studies also reported that autophagy activation alleviated local inflammation responses and skin aging. Previously, we have reported development of new autophagy activators in human epidermal keratinocytes. Significant anti-inflammatory activities and anti-aging effects were observed for those newly developed autophagy activators. In this talk, practical application of those developed compounds as cosmetic ingredients will be discussed.

Measurement of Skin Hydration Using IoT Devices

( Sekyoo Jeong ),( Jongmi Lim ),( Heyjin Song ),( Changhee Han ),( Hyunjung Kim ) 한국피부장벽학회 2016 한국피부장벽학회지 Vol.18 No.1

Non-invasive measurement of skin functions, such as epidermal permeability barrier function, skin hydration and skin surface pH, generally requires specialized apparatus and controlled environmental conditions (i.e., temperature and relative humidity). While these data can provide invaluable information about the skin functions, they can only represent skin functions under specific experimental conditions. In order to analyze the changes of skin functions according to the practical environmental changes, such as by seasonal change or air pollution status, large number of data sets over a long-term measurement period are required. Considering the price and measurement protocols, classical measurement apparatuses are not practically applicable for these kinds of studies. Recent advances in IoT (internet of things) technology and sensor technology have made it possible for developing various kinds of wearable devices, which can track and record enormous number of data sets from human behaviors. Recently, we developed a portable device that measures the skin hydration and stores the data using IoT technology. Hypothetically, it can provide enough data sets which make it available to analyze the overall tendency of skin functions. While there are clear limits of these approaches, such as uncontrolled measurement conditions and non-standardized measurement protocols, big data analysis may overcome these limitations. In this talk, results of preliminary study will be discussed and further study plans with the device will suggested.

Skin Microbiome for Cosmetic Application

( Sekyoo Jeong ) 한국피부장벽학회 2019 한국피부장벽학회지 Vol.21 No.1

Microbiome, also referred as metagenome of the microbiota, comprises all of the genetic material within a microbiota (the entire collection of microorganisms in a specific niche, such as the human gut). Owing to the great evolution of gene analysis technology, in terms of cost and accuracy, metagenome analysis of human derived samples and their statistical analysis became quite popular in nearly every fields of health industry. Since the first identification of potential relationship between microbial diversity and disease severity in atopic dermatitis, skin microbiome has been an important and attractive target in dermatological research. Initiated as an effort to develop new ingredients for either acne or acne-prone skin, skin microbiome research in cosmetic industry keeps expanding into nearly every area such as anti-aging and sensitive skin. Another important merits of skin microbiome in cosmetic application is the possibility of enormous diversity based on each individual’s micro-environment, life-style, and physical and psychological health status, which can support the concept of personalized cosmetics. With the increasing interests, however, practical application of skin microbiome in cosmetics is not yet available. In this review, current status of microbiome research in cosmetic industry and perspectives will be briefly discussed. Also, metabolomics-based interpretation of skin microbiome will be also suggested.

Practical Application of Autophagy Activator as a Cosmetic Ingredient

정세규 ( Sekyoo Jeong ) 한국피부장벽학회 2017 한국피부장벽학회지 Vol.19 No.2

보습제와 피부 지질 -피부 지질을 중심으로 본 보습제의 기능

정세규 ( Sekyoo Jeong ) 한국피부장벽학회 2015 한국피부장벽학회지 Vol.17 No.2

Along with the epidermal lipids and sebaceous gland-secreted lipids, exogenous lipids originated from topical products, pollution, and microbial metabolism, also importantly comprise the skin surface lipids. As one of the most commonly applied products on the skin, moisturizers can affect various features of skin lipids, including physical properties and biological activities. Emulsion formulation contains mainly water, lipids, emulsifiers, and other ingredients such as bioactive materials. In this talk, the effects of each component on the skin lipids will be briefly discussed.

Autophagy Activation by <i>Crepidiastrum Denticulatum</i> Extract Attenuates Environmental Pollutant-Induced Damage in Dermal Fibroblasts

Yoon, Seok Jeong,Lim, Chae Jin,Chung, Hwa-Jee,Kim, Joo-Hwan,Huh, Yang Hoon,Park, Keedon,Jeong, Sekyoo MDPI AG 2019 INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES Vol.20 No.3

<P>Pollution-induced skin damage results in oxidative stress; cellular toxicity; inflammation; and, ultimately, premature skin aging. Previous studies suggest that the activation of autophagy can protect oxidation-induced cellular damage and aging-like changes in skin. In order to develop new anti-pollution ingredients, this study screened various kinds of natural extracts to measure their autophagy activation efficacy in cultured dermal fibroblast. The stimulation of autophagy flux by the selected extracts was further confirmed both by the expression of proteins associated with the autophagy signals and by electron microscope. <I>Crepidiastrum denticulatum</I> (CD) extract treated cells showed the highest autophagic vacuole formation in the non-cytotoxic range. The phosphorylation of adenosine monophosphate kinase (AMPK), but not the inhibition of mammalian target of rapamycin (mTOR), was observed by CD-extract treatment. Its anti-pollution effects were further evaluated with model compounds, benzo[a]pyrene (BaP) and cadmium chloride (CdCl<SUB>2</SUB>), and a CD extract treatment resulted in both the protection of cytotoxicity and a reduction of proinflammatory cytokines. These results suggest that the autophagy activators can be a new protection regimen for anti-pollution. Therefore, CD extract can be used for anti-inflammatory and anti-pollution cosmetic ingredients.</P>

Enhanced Large-Scale Production of Hahella chejuensis-Derived Prodigiosin and Evaluation of Its Bioactivity

( Yu-jin Jeong ),( Hyun Ju Kim ),( Suran Kim ),( Seo-young Park ),( Hyeran Kim ),( Sekyoo Jeong ),( Sang Jun Lee ),( Moo-seung Lee ) 한국미생물 · 생명공학회 2021 Journal of microbiology and biotechnology Vol.31 No.12

Prodigiosin as a high-valued compound, which is a microbial secondary metabolite, has the potential for antioxidant and anticancer effects. However, the large-scale production of functionally active Hahella chejuensis-derived prodigiosin by fermentation in a cost-effective manner has yet to be achieved. In the present study, we established carbon source-optimized medium conditions, as well as a procedure for producing prodigiosin by fermentation by culturing H. chejuensis using 10 L and 200 L bioreactors. Our results showed that prodigiosin productivity using 250 ml flasks was higher in the presence of glucose than other carbon sources, including mannose, sucrose, galactose, and fructose, and could be scaled up to 10 L and 200 L batches. Productivity in the glucose (2.5 g/l) culture while maintaining the medium at pH 6.89 during 10 days of cultivation in the 200 L bioreactor was measured and increased more than productivity in the basal culture medium in the absence of glucose. Prodigiosin production from 10 L and 200 L fermentation cultures of H. chejuensis was confirmed by high-performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometry (LC-MS) analyses for more accurate identification. Finally, the anticancer activity of crude extracted prodigiosin against human cancerous leukemia THP-1 cells was evaluated and confirmed at various concentrations. Conclusively, we demonstrate that culture conditions for H. chejuensis using a bioreactor with various parameters and ethanol-based extraction procedures were optimized to mass-produce the marine bacterium-derived high purity prodigiosin associated with anti-cancer activity.

Autophagy activation decreases AGEs in skin cells in vitro and ex vivo

( Kayoung Shin ),( Yeonjae Kim ),( Sungwoo Kim ),( Sekyoo Jeong ),( Hwa-jee Chung ),( Keedon Park ),( Sungha Hwang ),( Dayeon Song ),( Minkyung Shin ),( Dabin Jeong ),( Jeong Ho Park ) 한국피부장벽학회 2023 한국피부장벽학회지 Vol.25 No.2

While the initial generation of AGEs (advanced glycation end products) usually takes place in a time-lapse of hours, it is reported that the complete formation of AGEs after the rearrangement and cross-liking with other proteins requires weeks to years under physiological conditions. However, in pathological conditions such as hyperglycemia, oxidative stress, and higher temperature, it can be accelerated up to hour-scale reaction. While AGEs can mechanically and/or biochemically alters the protein and tissue structures and functions, AGEs can also elicit downstream cellular signaling through binding to the RAGE (receptor for advanced glycation end products). Activation of RAGE induces NF-κB and MAPK pathways and results in the release of various cytokines and matrix metalloproteinases (MMPs). In skin, along with the direct ultraviolet irradiation, exposure to particulate matters (PMs) or smoking can also accelerate the formation of AGEs, which subsequently induces irregular pigmentation, wrinkle formation, and skin barrier dysfunction. Based on the deleterious effects of AGEs on skin aging, significant efforts have been exerted to develop anti-AGE molecules. Most of the currently available anti-AGE molecules, however, focus on the prevention of AGEs through the anti-oxidant property of molecules. Autophagy is a cellular mechanism to maintain cellular homeostasis role by removing dysfunctional cellular organelles and proteins. Recently, it was reported that AGEs removal can be stimulated by autophagy activator treatment in human epidermal keratinocytes. In this study, using a newly developed compound derivative with autophagy stimulating activity and anti-oxidant capacity, we investigated the modulation of AGEs formation and elimination by autophagy activator in vitro and ex vivo. In cultured human epidermal keratinocytes, high glucose- or glyoxal-induced AGEs formation was attenuated by autophagy activator treatment. Removal of BSA-AGE by keratinocytes was also accelerated by autophagy activator. Similar activities were also observed in ex vivo human skin explant model. Interestingly, epidermal expression of RAGE was also down-regulated by autophagy activator treatment. These results suggest that autophagy signaling is closely related to AGEs formation and elimination, and stimulation of autophagic flux can be a new regimen for anti-AGEs therapeutics.