폴리올을 이용한 각질층 수분량 측정의 표준화 연구

남개원 ( Gaewon Nam ) 대한화장품학회 2015 대한화장품학회지 Vol.41 No.2

The measurement of hydration level in the surface layer of the skin, stratum corneum (SC), gives important information on the biophysical properties and function of the skin barrier such as softness, flexibility, and healthiness of the skin. But it is difficult to measure a consistent hydration level from a sample to another sample due to individual variations and environmental changes. The aim of this study was to evaluate objective hydration after using various products in the SC. The SC Hydration was measured by capacitance (CorneometerⓇ, C+K, Germany) on the ventral site of forearm from 40 healthy volunteers. The skin surface was chronologically measured immediately after application of the test products and 3 and 6 hours later. We analyzed the averages of five measurements of each site and used the hydration increase rate for correction on untreated site variation. We found that most polyols including glycerol and butylenes glycol influenced directly the hydration increase rate in the SC previously. In this study, glycerol was used to prepare the standard products from 0 to 20 percents and applied to the same volunteers. The individual standard curve showed linear relation to glycerol concentrations. Based on the the standard curve, hydration of SC was converted into hydration increase rate to glycerol concentrations. The converted glycerol concentrations of products were repetitive and reproducible. In addition, the individual standard curve was used to relate the skin type of each individual. These results suggest that the hydration of the SC standardized regardless of external variation and individual skin condition can explain detailed skin state variation. Further studies will be conducted with other ingredients such as surfactants, lipids and aqueous materials, and with other methods for noninvasive measurement.

Adenophorae Radix 뿌리 추출물에 의한 Keratinocyte의 분화 및 피부장벽 기능에 대한 연구

남개원 ( Gaewon Nam ) 대한화장품학회 2017 대한화장품학회지 Vol.43 No.4

We have studied on the keratinocytes differentiation and skin barrier function using Adenophorae radix (A. radix) root extract, which was known to contain triterpenoid, saponin and starch. A. radix root extracts showed the PPARα expression level of Wy-14,643 0.5-1.0 μM in CV-1 cells. The cornified envelop formation (CE) of human keratinocyte cell line (HaCaT) and normal human keratinocyte (NHK) showed a statistically significant increased compared to the control. When HaCaT cells were treated with A. radix root extract, transglutaminase (TGase-1) was significantly increased. As a result of clinical study of the simple cosmetic formulation containing A. radix root extract for about 2 weeks, TEWL values were significantly decreased and water contents were increased. The ceramides, which were obtained from the inner forearm, were also significantly increased statistically. We suggest that the A. radix root extract can be used as a preventive and therapeutic agent for skin diseases such as dry skin and atopy.

pH에 따른 하이드록시 산(Hydroxy Acid)의 각질 박리 효과 연구

남개원 ( Gaewon Nam*† ) 대한화장품학회 2016 대한화장품학회지 Vol.42 No.4

Hydroxy acid has been used to enhance anti-aging and skin moisturization by peeling effect on the skin stratum corneum, and thus it has been widely used in topical products and cosmetic products. Among them, the effect that appears most effectively in a short period of time has been reported to be effected by the pH of the cosmetic formulations. However, there are many difficulties in use due to irritation caused by pH and concerns about side effects. The purpose of this study was to evaluate the effect of applying cosmetics with (1) varying concentrations, (2) types and (3) pH of hydroxy acid on human skin. 22 healthy adults were stained with DHA (dihydroxyacetone) and DC (dansyl chloride) on the forearm, and the skin exfoliation effect was measured after application of the test products. (1) The application of GA (glycolic acid) increased the desquamation by concentration dependent. (2) the test product prepared with neutral pH showed no exfoliation effect. In contrast, SA (salicylic acid) showed a statistically significant exfoliation effect at both acidic pH and neutral pH. (3) The neutral pH SA showed excellent exfoliation effect on both DHA and DC stained stratum corneum. These results suggest that it is possible to manufacture safe cosmetics without damaging the skin barrier, providing an opportunity to use cosmetics that are expected to exfoliate to people, whose skin is sensitive to pH.

케라틴 펩타이드에 의한 모발 및 두피 특성 변화 연구

남개원 ( Gaewon Nam ) 대한화장품학회 2019 대한화장품학회지 Vol.45 No.4

Using Fervidobacterium islandicum AW-1, keratin peptides were produced and confirmed factors related to the scalp and hair. The cytotoxicity and proliferation tests as a function of the concentration of the keratin peptide did not show toxicity and effect on the cellular proliferation in the immortalized human hair dermal papilla cell line. Hair shampoos and hair essences containing keratin peptides were produced, and conducted human patch test. Result showed no skin irritation. The shampoo and the essence were apploed to 2 groups of 30 healthy adults for 4 weeks and showed statistically significant positive results for gloss, hair loss, scalp trouble, and hair roughness by visual assessment. The scalp water content was significantly increased after 2 and 4 weeks compared to before using the shampoo or the essence. Trans-epidermal water loss (TEWL) and the sebum secretion amount in the scalp were significantly decreased after 4 weeks compared to before. The frictional force against combing before and after using the hair shampoo and the essence for normal hair tress and damaged hair tress was significantly changed. The combing force was increased for normal hair tress and decreased for damaged hair tress. In conclusion, we suggest that keratin peptides are appropriated as cosmetic ingredients to be used in hair and scalp related products.

Recent Studies of Skin Barrier Research

( Jimin So ),남개원 ( Gaewon Nam ) 한국피부장벽학회 2019 한국피부장벽학회지 Vol.21 No.1

The epidermis, the outermost layer of the skin, functions as skin barrier. The epidermis regulates the outside-in and inside-out penetration of water, nutrients, ions and environmental stimuli. Epidermal cells continuously regenerating, thus to understand dynamically changing characteristics and functions of epidermis, it is important to observe viable epidermal tissues. 3D imaging technique can be used to observe live tissue, however is not suitable for human tissues. Instead, in vitro artificial 3D human epidermis can replace human tissues. 3D skin model is in vitro developed 3-dimensional model mimicking native human skin. It is now broadly used to replacement for animal experiments. 3D skin models have numerous uses. They can be applied to permeability test, toxicity test as well as efficacy test for drugs and cosmetics. In this review, we summarize comprehensive understanding of 3D skin models for skin barrier function study. We report development and application of 3D skin models, current limitations of its use and directions of further investigations.

3D 측정 기기를 이용한 얼굴의 부피 정량법 연구

박신영 ( Shinyoung Park ),남개원 ( Gaewon Nam ),김승훈 ( Seunghun Kim ),이해광 ( Heakang Lee ),안성연 ( Sungyeon Ahn ),문성준 ( Seongjoon Moon ),김한곤 ( Hankon Kim ) 대한화장품학회 2008 대한화장품학회지 Vol.34 No.4

The evaluation for the visage volume was performed with human and dummy face using PRIMOS body^Ⓡ. Three researchers measured the dummy face attached different volume of clay (6.6 mL, 13.2 mL, and 19.8 mL). It is identified that the high correlation between measured values and real volume (R² = 0.99). The percent (%) of relative standard deviation (RSD) of the data was shown below 10 %. In Gage R&R analysis, the percent of contribution, the percent of study variation and distinct categories values were 0.78 %, 8.85 %, and 15 % respectively. Therefore this method was regarded as the good standard condition in aspect of reproducibility and repetitiveness of data. The face volume variation was measured by PRIMOS body^Ⓡ on the face in participated 10 healthy Korean women volunteers. Subjects used the product once a day for two weeks as night sleeping pack. After application of the test products, the 3D image data of face were taken 1 and 2 weeks later. We found the face volume was significantly decreased after using products. In conclusion, this novel non-invasive technique was useful in measuring and visualizing alterations in face volume as a consequence of certain treatments. This system will provide a rapid and precise analysis of 3D topographical information for face.

Stratum Corneum Carbonylated Protein (SCCP)의 피부 생물학적 파라미터와의 관계

이용직 ( Yongjik Lee ),남개원 ( Gaewon Nam ) 대한화장품학회 2019 대한화장품학회지 Vol.45 No.2

Carbonylated proteins (CPs) are synthesized by the chemical reaction of basic amino acid residues in proteins with aldehyde compounds yielded by lipid peroxidation. CPs are excited by a range of light from UVA to blue light, and resulted in the generation of superoxide anion radicals (^·O₂^-) by photosensitizing reaction. Then, they CPs induce new protein carbonylation in stratum corneum through ROS generation. Furthermore, the superoxide anion radicals produce CPs in the stratum corneum (SC) through lipid peroxidation and finally affects skin conditions including color and moisture functions. The purpose of this study was to investigate the relationship between the production of stratum corneum carbonylated protein (SCCP) and the skin elasticity. 46 healthy female Koream at the ages of 30 ∼ 50 years old were participated in this study for 8 weeks. The skin test was experiment conducted into two groups; placebo group (N = 23) used cream that did not contain active ingredients, and the other group (N = 23) used cream containing the elasticity improving ingredients. Test areas were the crow ‘s feet and the cheek. Various non-invasive methods were carried out to measure biophysical parameters on human skin indicating that dermis density and skin wrinkle were measured by using DUB scanner and Primos premium, respectively. Skin elasticity were measured using dermal torque meter (DTM310) and balistometer (BLS780). SCCP was assessed in a simple and non-invasive method using skin surface biopsy on the cheek of the subject. The amount of SCCP was determined using image analysis. All measurements were taken at 0, 4 and 8 8week. Results revealed that the amount of CP in SC was reduced when the skin wrinkle and skin elasticity related parameters were improved. This indicates that the correlation between the elasticity improvement and the amount of CP can be used as a anti-aging indicator and applicable to the skin clinical test for the measurement of skin aging in the future.

한국 여성의 피부 부위 및 연령에 따른 피부 측정 인자와 생물 인자 연구

조석철 ( Seok-cheol Cho ),남개원 ( Gaewon Nam ) 대한화장품학회 2015 대한화장품학회지 Vol.41 No.4

The skin is one of the largest organs in our body and participates in many of the human organism’s physiological and pathological events. Skin function were known for self-maintenance and self-repair, mechanical and chemical stress protection, protection against UV and environmental pathogenic micro-organisms, production of vitamin D, and social and psychological function through the physical aspect. The aim of this study was to evaluate the variation of biophysical parameters and to find relation with skin biomarkers in different anatomical site and age in Korean women. About 70 healthy volunteers in age range 20 to 49 were participated in this test. Test areas were the forearms and the cheek. Investigation to determine biophysical parameters on human skin, was carried out using various non-invasive methods. For analysis to skin biomarkers, we studied to examine various biomarkers for the quantitative determination of cortisol, fibronectin, keratin-1, 10, and 11, involucrin, and keratin-6 in human face and forearm. And we measured to skin biophysical parameters for skin anatomical site and age difference with non-invasive methods. As results of measuring site, some parameters were have following significant difference, stratum corneum hydration, trans epidermal water loss and skin color (L and a value). As results of age difference, skin colors were had only significant difference with age. For cortisol, keratin-6, fibronectin, keratin-1, 10, 11 contents, there were no significant difference in age and site. However, involucrin level in the cheeks were the highest for age group 30 ∼ 39 compared to other age groups. These results suggest that in individual skin condition may explain detailed skin state variation.

극성 저분자 케라틴 펩타이드에 의한 피부 탄력 변화 연구

맹지혜 ( Jihye Maeng ),남개원 ( Gaewon Nam ) 대한화장품학회 2020 대한화장품학회지 Vol.46 No.3

Using Fervidobacterium islandicum AW-1, polar low molecular weight keratin peptides were produced and confirmed through factors related to the skin elasticity. As a result of confirming the cytotoxicity and collagen synthesis ability according to the concentration of the polar low molecular weight keratin peptide in human fibroblasts, it was confirmed that the cytotoxicity did not appear and the collagen synthesis in human fibroblasts was increased. A mask pack containing a polar low-molecular weight keratin peptide was used, and a test product was used for 4 weeks in 22 healthy women subjects. As a result, it showed statistically significant effects on skin elasticity, skin torsion elasticity, skin color and moisture improvement. Through this test, it was confirmed that the polar low-molecular keratin peptide can be used as a cosmetic ingredient that helps improve skin elasticity.

Confocal Scanning Laser Microscope (CSLM)을 이용한 신규 미백 효과 측정 연구

김명기 ( Myong Ki Kim ),조석철 ( Seok-cheol Cho ),남개원 ( Gaewon Nam ) 대한화장품학회 2015 대한화장품학회지 Vol.41 No.3

Hyperpigmentation on face is a highly anxiety-producing symptom, especially for women from the aspect of beauty. Pigmentation of the skin is related to the amount of melanin that provides protection against UV radiation. In vivo reflectance confocal microscopy is a non-invasive imaging tool allowing visualization of the skin without tissue alteration, by placing a microscopy directly on the living skin. The aim of this study was to develop the new evaluation method of whitening effects using in vivo reflectance confocal microscopy and to validate other instruments for measuring skin colors, and UV-induced hyperpigmentation was elicited on the inside skin of the forearm. It suggested that the new method for whitening effects using the confocal microscopy was useful to evaluate the de-pigmentation products and to easy for understanding to customers.