Skin Water Content Research Articles

皮膚のバリア機能および水分量の可視化

「角層バリア機能」と「角層水分量」が高い状態にあることが美容分野において美しい皮膚の要件とされている。通常これらの皮膚パラメーターは数値データとして機器測定するが，これらの測定方法では点での測定に限られており，可視化して二次元で観察することができない。近年，「角層バリア機能」はフルオレセイン塗布した皮膚を蛍光マイクロスコープで観察することにより，また「角層水分量」は近赤外（NIR）カメラにより可視化することができるようになった。これらの可視化技術により二次元での皮膚計測が可能になり，皮膚状態をより詳細に把握することが可能になった。

Development of an in-vivo sensor for monitoring of water content in skin

AbstractA change in the water distribution of the human body, such as water retention in the skin, can be a symptom of a pathological condition including heart failure. Therefore, a sensor for the non-invasive quantification of the water content of the skin could be useful where continuous monitoring of patients is required to detect and avoid life threatening conditions. As water is a major absorber of tissue in the near-infrared wavelength range, the water content can be determined based on reflectance measurements. Measuring the diffuse reflectance at multiple distances from the point of illumination allows the determination of absorption in scattering media such as skin. The aim of this project was to develop a small and portable sensor based on light emitting diodes and photodiodes. Evaluation of the first functional sensor design has showed that the water content of tissue phantoms can be predicted with a prediction error of 1%. Further developments towards a sensor that can be applied in a future field study are ongoing.

Use of reflectance near-infrared spectroscopy to investigate the effects of daily moisturizer application on skin optical response and barrier function.

A number of noninvasive techniques and instruments have emerged over the years allowing much progress toward clarifying the structure and function of human skin and studying the effects of various applied substances. All of this research has provided great insight into the interactions between skin and various products through quantitative and qualitative measurements. Such methods include near-infrared spectroscopy (NIRS), a technique which has gained popularity over the years and has often been employed to accurately determine the moisture levels and water content of skin based on its sensitivity to hydrogen bonding. NIRS has also been applied in many studies to report the efficacy of moisturizing products and assess their benefits to the skin. However, many of these studies have reported an increase in skin water content following moisturizer application while some have challenged the benefits of long-term moisturizer use, particularly on normal skin, and even suggested that it can increase the skin's susceptibility to irritants. This paper reports the results of a pilot in vivo study carried out on the skin of 20 healthy volunteers, categorized into groups depending on their skin type and frequency of moisturizer use, in order to investigate the optical response of human skin after direct short-term contact with water followed by application of a moisturizer. The measurements were obtained using a highly advanced spectrophotometer in the region of 900 to 2100 nm equipped with a customized reflectance fiber optic handheld probe. Scatter graphs of group results and second derivative spectra have shown an interesting pattern between frequent users of moisturizers and individuals who do not use moisturizers, suggesting that long-term daily moisturization may have an effect on skin barrier function. The results also raise some questions regarding the optical characteristics of different skin types, as well as the varying response between different water bands in the NIR region. Future work will focus on gaining more knowledge about these subjects and obtaining results from a larger population, as well as performing statistical analysis through regression methods in order to further improve optical skin measurements.

Investigating skin barrier function utilizing reflectance NIR spectroscopy.

Near Infrared Spectroscopy is seen as a potentially valuable technique for skin analysis, and has been employed by many previous studies to measure skin hydration, since it is competent of providing information regarding various functional groups including OH, CH and NH bands. The aim of this study was to investigate the capability of further utilizing this method by attempting to analyze skin barrier function as well as water content, through the evaluation of skin water uptake on two test sites, one untreated, and another treated with a high lipid moisturizer for a period of 7 days. Reflectance NIRS measurements were supported by capacitance readings obtained using the Corneometer® CM 825. Baseline recordings taken on the first day following treatment showed that more differences were observed between the treated and untreated sites in the regions belonging to, or are influenced by CH and NH groups rather than purely on the water bands. On the hand, moisture levels measured after placing a wet patch on the skin remained nearly equal for both sites but second derivative spectra showed that a clear contrast existed between absorbance heights at the water bands of the treated and untreated, suggesting that moisturizer use could have limited water uptake to a more superficial layer of the skin, whereas for the untreated site, the opposite would have been true and water was able to penetrate deeper. Overall, results here suggest that NIR spectroscopy can possibly provide valuable information not only on skin water contents but perhaps on other skin parameters such as barrier function.

Skin photoprotection and consumption of coffee and polyphenols in healthy middle-aged Japanese females.

Reactive oxygen species are known to mediate skin photoaging, which results in the formation of pigmented spots and wrinkles. Coffee is the largest source of polyphenols, which supplies a large number of antioxidants in one's daily life. However, little is known about how much coffee and polyphenol consumption influences skin health. In this study, a cross-sectional survey of the diet, environmental factors, and skin conditions was conducted in healthy Japanese females to explore the influence of coffee and polyphenol consumption on skin conditions. Non-smoking, healthy female subjects with moderate sun exposure in their daily lives were recruited for this study (n=131, age range: 30-60years old) and recorded their food and beverage intake and life circumstances using questionnaires. The skin water content, transepidermal water loss, and elasticity were measured on the cheek of each subject using non-invasive methods: a Corneometer, a Tewameter, and a Cutometer, respectively. Wrinkles and pigmented spots were evaluated using digital photograph images. Consumption of coffee and total polyphenols from all sources and from coffee showed a statistically significant correlation towards a decrease in pigmented spot scores (P<0.05). Subjects with high total polyphenol consumption from coffee or chlorogenic acids (the third tertile group) showed the lowest score of ultraviolet pigmented spots (P<0.05). Coffee and polyphenol consumption was associated with low facial pigmented spots in Japanese middle-aged females. We speculated that coffee helps protect human skin from photoaging, and polyphenols, including chlorogenic acids, may contribute to the decreased hyperpigmentation of pigmented spots.

A layered sensor for simultaneous measurement of skin water content and softness

In this paper, a layered sensor was developed for simultaneous measurement of skin water content and softness. The sensor consisted of a thin stainless steel film on top of a polyvinylidene difluoride (PVDF) film. Electrostatic and piezoelectric effects generated voltages which were measured simultaneously in the stainless steel and PVDF films while the sensor was repeatedly in contact with/released from the skin. The voltages in the films depended on the skin water content and softness. The layered sensor measured the skin water content and softness at the same position using the voltage waveforms. The relationships between the voltages obtained using the layered sensor and results obtained with commercial moisture and softness sensors were evaluated. The potential of the proposed sensor for skin condition measurements was evaluated.

Purification, characterization and promoting effect on wound healing of an exopolysaccharide from Lachnum YM405

An exopolysaccharide (LEP-2b) with molecular weight of 2.8×104Da was isolated from Lachnum YM405 and purified by DEAE-cellulose 52, Sepharose CL-6B chromatographic column. It consisted of rhamnose (Rha), mannose (Man), glucose (Glc) and galactose (Gal) in a molar ratio of 1.0:5.0:11.5:12.5. Its backbone consisted of →4)-β-d-Manp-(1→, →2)-α-d-Rhap-(1→, →6)-β-d-Glcp-(1→, and →6)-α-d-Galp-(1→, and three types of branches were composed of →6)-α-d-1-OMe-Manf-(2→, →6)-β-d-1-OMe-Manf-(2→, →1)-α-d-Galp-(6→, →1)-β-d-Galp-(6→, and →1)-β-d-Glcp, which were at O-3 of 1,3,6-linked α-d-Manp and O-2, O-3 of the same 1,2,3,6-linked β-d-Glcp in the backbone respectively. LEP-2b ointment significantly accelerated the decrustation of the wounded skin, shortened the healing time and increased the water and hydroxyproline contents of the healed skin. Combined with the results of macroscopic and histological observations, we deemed that LEP-2b could inhibit inflammatory reaction of scalded skin, accelerate tissue repair and re-epithelialization, thereby playing a positive role in promoting wound healing.

Physiological effect of olfactory stimuli inhalation in humans: an overview

The importance of odorants in human life has long been recognized. Literature contains different approaches of physiological and psychological effects of odorant compounds, fragrances and essential oils. This work discusses odorants inhalation effect, based on an overview of major studies in humans. Beneficial effect of fragrances is mainly related to human behaviour. Studies document odorants influence in sympathetic and parasympathetic nervous systems, and neurophysiological brain activity. Moreover, odours compounds can act on the neuroendocrine system, neurotransmitters and neuromodulators, influencing psychological behaviour as well as body function. Odorant inhalation modulates physiological pathways, and in some cases, results in skin function regulation. The mechanism is incompletely elucidated. These findings suggest that olfactory system plays a role in central nervous system function beyond that of smell. In this overview, it was observed that odour compounds influenced stress biomarkers, dehydroepiandrosterone, oxidative stress, estradiol, dopamine, cutaneous barrier, sebum secretion and cutaneous immune system in humans. Some can be related with skin function. As the skin is associated with an extensive biochemical cascade and has complex mechanisms, studies have far to go, as there are processes not yet investigated related to skin that may be affected through olfaction. Future researches are needed to further understand and describe the mechanisms of action of physiological effects in fragrance compounds.

Confocal Raman spectroscopy: determination of natural moisturizing factor profile related to skin hydration

INTRODUCTION: Skin health and skin care to reduce the effects of aging are the main interests of many researchers. The skin is very important because it protects the body from various effects of the external environment, and studies of the largest organ of the human body have been conducted since antiquity. In skin, aging effects are severe enough to promote changes in cell structure and biochemical composition. In this study, we quantitatively analyzed the water content and natural moisturizing factor of human facial skin in vivo and in real time by confocal Raman spectroscopy. This non-invasive technique is capable of providing detailed information on the biochemical composition at different depth profiles in the skin. METHODS: We studied 10 volunteers, phototype II (40 and 50 years old), using a confocal Raman system to examine the skin surface down to 25 µm. Raman spectra were obtained before product use (T0), and after 30 days of continuous use of cosmetics (T30). RESULTS: The results show a significant increase of 6.4% in water content in the surface layer of the facial skin after the cosmetic use. The amounts of natural moisturizing factor (NMF) compounds were also increased. Urocanic acid underwent a greater change in relation to carboxylic acid pyrrolidone, with a 38.5% increase in the stratum corneum. CONCLUSION: Confocal Raman spectroscopy identified changes in the biochemical composition of the superficial layers of the epidermis, which suggests the anti-aging efficacy of the formulation.

透析患者における皮膚水分量の特性ならびに痒みとの関係

【目的】透析患者に高頻度で認められる瘙痒症および皮膚乾燥症の特性ならびに両者の関係を明らかにする. 【対象と方法】血液透析患者450名において, 痒みに関するアンケート調査を実施するとともに, 前腕内側部および腰背部の皮膚水分量を測定した. 【結果】全体の65.6%が痒みを自覚していた. 腕および背中の水分量の中央値は, それぞれ30.9%および31.2%であり, 両者間に正の単相関関係が認められた. 一方, 腕および背中の水分量と, 性別, 年齢, 透析歴, 糖尿病の有無, 痒みの有無, 痒みの頻度, 痒みの程度 (VAS値), 睡眠障害の有無, 治療の有無, 外用薬の有無, 治療満足度との間に関連性は認められなかった. 重回帰分析の結果, 痒みの有無と関連する因子として, 男性, 糖尿病, 透析後未補正血清Caが, また, 水分量と関連する因子として, 透析後血清Na, 透析前補正血清Caが選ばれた. 【結語】血液透析患者において, 皮膚水分量は瘙痒症の有無および程度と関連しない.

한국인의 피부 수분함유량, 유분 함유량 및 경표피수분손실량의 특성에 관한 연구

본 연구에서는 연령별 수분함유량, 유분함유량 및 경표피수분함유량에 대한 데이터를 비교 분석함으로써 연령별 피부 특성 차이를 규명하여 향후 화장품 산업개발에 도움을 줄 수 있는 기초자료를 제공하고자 한다. 피험자 남녀 총 638명을 대상으로 볼 부위의 수분함유량, 코 끝 부위의 유분함유량, 볼과 전박부위의 경표피수 분손실량을 측정하였으며, Statistical Package for the Social Sciences (version 19.00; SPSS Inc., Chicago, IL, USA) 프로그램을 사용하여 분석하였고 피험자에 대한 정보뿐 아니라 피부 수분함유량, 유분함유량, 경표피수분손실량의 피부 측정치 결과를 평균 <TEX>${\pm}$</TEX> 표준편차로 나타내었다. 그 결과 볼 부위의 수분함유량은 여성이 남성보다 높았으며, 연령이 높아질수록 수분함유량이 증가하였다. 또한 코 부위의 유분함유량은 남성이 여성보다 높았으며 연령이 낮아질수록 유분함유량이 증가하였다. 볼 부위의 경표피손실량은 여성이 남성보다 높은 반면, 전박 부위의 경표피손실량은 남성이 여성보다 높았다. 이상의 연구 결과로 추후 화장품 산업에서 연령별, 성별 기초화장품 개발 등에 도움을 줄 수 있는 기초자료로 활용될 수 있을 것이라 사료된다. In this study, water content, sebum content, and transepidermal water content were investigated to provide basic data for the future cosmetics industry as comparing the skin characteristics of different ages. Water content of cheek area, sebum content of nose area, and transepidermal water loss (TEWL) of cheek and forearm of trial subjects (total 638 people of both male and female) were measured. Data were analyzed using Statistical Package for the Social Sciences program (version 19.00; SPSS Inc., Chicago, IL, USA). Water content, sebum content, and TEWL of skin were measured as mean <TEX>${\pm}$</TEX> standard deviation. As a result, water content of cheek from female was higher than male and the water content increased with the older ages. However, sebum content of nose from male was higher than female and the sebum content increased with the younger ages. TEWL of cheek from female was higher than male, but TEWL of forearm from male was higher than female. Therefore, these results can be used as basic data in the development of future cosmetics for different ages and genders.

Good agreement between minimal erythema dose test reactions and objective measurements: an in vivo study of human skin

The erythema resulting from the minimal erythema dose (MED) test is subjectively assessed. The evaluator visually grades erythema on an ordinal scale. Both intra- and interobserver variation have been found for this erythema assessment. We wanted to examine if objective measurements could be used to confirm the subjective finding. One hundred two ultraviolet radiation (UVR)-exposed skin sites on the backs of 17 healthy volunteers were assessed. Erythema was visually graded according to a 5-point scale [0, (+), 1+, 2+, 3+] and objectively measured by a skin reflectance meter. Skin water content was objectively measured by tissue dielectric constant measurements. The relationship between subjective assessments and objective measurements of erythema was found to be linear (R(2) = 0.482, P < 0.0001). A positive correlation was found between subjective assessments of erythema and objective measurements of water content (Spearman's Rho = 0.414, P < 0.0001). Water content in categories 2+ and 3+ of the subjective erythema assessments differed significantly from the lesser categories (P < 0.0001). A linear relationship was found between the objective measurements of erythema and water content (R(2) = 0.241, P < 0.0001). Objective measurements of skin erythema and water content after UV exposure were in good agreement with the subjective assessments of erythema, but showed considerable interpersonal variation.

Methanol extract of Ulmus pumila. L exerts potent anti‐inflammatory effects in murine macrophages and mouse skin

Ulmus pumila.L has been reported to be used as an oriental medicine for treating inflammation for centuries, but the effects and mechanism of its action have not been fully characterized. In this study, we investigated the in vitro and in vivo anti‐inflammatory effect of methanol extract of Ulmus pumila (UP). UP was found to inhibit significantly LPS‐induced nitric oxide (NO) in RAW 264.7 cells. UP significantly reduced the mRNA expression of pro‐inflammatory cytokines including TNF‐α, iNOS, IL‐1β, COX‐2 and IL‐6 in LPS‐stimulated RAW 264.7 cells. Moreover, nuclear translocation of p65 subunit was also dose dependently suppressed by UP treatment. In addition, UP also inhibited phorbol ester‐induced increase in ear swelling and skin water content in BALB/c mice. These results suggest that UP can be a potential candidate for inhibiting inflammation and can be used for the development of new anti‐inflammatory agents.

23 Na Magnetic Resonance Imaging-Determined Tissue Sodium in Healthy Subjects and Hypertensive Patients

High dietary salt intake is associated with hypertension; the prevalence of salt-sensitive hypertension increases with age. We hypothesized that tissue Na(+) might accumulate in hypertensive patients and that aging might be accompanied by Na(+) deposition in tissue. We implemented (23)Na magnetic resonance imaging to measure Na(+) content of soft tissues in vivo earlier, but had not studied essential hypertension. We report on a cohort of 56 healthy control men and women, and 57 men and women with essential hypertension. The ages ranged from 22 to 90 years. (23)Na magnetic resonance imaging measurements were made at the level of the calf. We observed age-dependent increases in Na(+) content in muscle in men, whereas muscle Na(+) content did not change with age in women. We estimated water content with conventional MRI and found no age-related increases in muscle water in men, despite remarkable Na(+) accumulation, indicating water-free Na(+) storage in muscle. With increasing age, there was Na(+) deposition in the skin in both women and men; however, skin Na(+) content remained lower in women. Similarly, this sex difference was found in skin water content, which was lower in women than in men. In contrast to muscle, increasing Na(+) content was paralleled with increasing skin water content. When controlled for age, we found that patients with refractory hypertension had increased tissue Na(+) content, compared with normotensive controls. These observations suggest that (23)Na magnetic resonance imaging could have utility in assessing the role of tissue Na(+) storage for cardiovascular morbidity and mortality in longitudinal studies.

Comparing the rates of absorption and weight loss during a desorption test using near infrared spectroscopy

The importance of determining skin hydration has over the years prompt the development of many instruments and methods, specifically designed to assess this parameter or water contents especially in the stratum corneum, and have greatly matured to suit different anatomical sites and measure multiple attributes. Of those, Near Infrared Spectroscopy (NIRS) has gained wide interest as a precise, safe, fast and noninvasive technique for determining skin hydration due to its high sensitivity to hydrogen bonding and ability to measure the amount of water in skin directly using the intensities of overtone and combination bands of OH and HOH water bonds occurring in the NIR region, that are good indicators of the state of skin hydration. This paper reports near infrared spectrophotometric measurements using a highly sophisticated spectrophotometer in the region of 1000-2500nm to study the water uptake and dehydration properties of skin in vitro using samples of porcine skin. Initial results of pure liquid water and skin samples have clearly displayed the prominent bands associated with water content, and desorption tests have been able to verify changes in these bands associated with water content, although a clear correlation between the rates of weight loss and absorbance loss at various hydration periods has not yet been established. These preliminary results are expected to further explain the relationship between water and skin, and its role within, in hope to aid the future development of a portable instrument based on near infrared spectroscopy that would be capable of directly measuring skin hydration and/or water content in a fast and noninvasive manner.

Warming of one hand causes sustained increases in skin surface temperature and water content of the contralateral forearm

Warming of one hand causes sustained increases in skin surface temperature and water content of the contralateral forearm

Skin Tissue Water Assessed via Tissue Dielectric Constant Measurements in Persons With and Without Diabetes Mellitus

Skin changes in diabetes mellitus (DM) include possible increases in foot skin water content as interpreted from altered echogenicity in high-frequency ultrasound images. The present goal was to investigate the possibility of undetected increased local skin water in persons with DM using a handheld portable rapid measuring device that measures the tissue dielectric constant (TDC) as an indicator of skin tissue water. TDC measurements were done bilaterally on 18 persons with DM and 18 persons without DM (NODM) at foot dorsum and anterior forearm to tissue depths of 0.5, 1.5, and 2.5 mm. DM duration was 11.1 ± 10.9 years. Age, body mass index, and blood pressures were not significantly different between groups. NODM and DM TDC values decreased with increasing depth at forearm but were depth independent at foot dorsum. All DM foot TDC values were significantly (P<0.05) greater than for NODM, with foot TDC values at 2.5 mm depth being 14.8% greater than in NODM. DM forearm TDC values were not significantly greater than NODM. A technology that characterizes local skin water in a rapid and noninvasive way has been used for the first time in persons with DM. The greater TDC value at the foot dorsum of the DM group is consistent with the presence of previously unrecognized increased fluid content. This suggests that there may be benefit utilizing this measurement method as a way to screen for early changes in foot skin features that may tend to cause DM-related edema.

Abstract 180: Interleukin (IL) 16 Acts as a Regulator of Skin Electrolyte Metabolism and Blood Pressure

We showed that Na + is stored in the skin without commensurate water retention. In response to interstitial electrolyte load, mononuclear phagocyte system (MPS) cells secrete VEGF C, as regulated by tonicity enhancer binding protein (TonEBP) attaching to the VEGF C promoter. VEGF C induces hyperplasia of skin lymphcapillaries. As IL16 harbors a TonEBP binding site, we tested the hypothesis that IL16 participates in this process. We cultured bone marrow-derived macrophages in isotonic or hypertonic cell culture media and measured IL16 expression. We fed male FVB mice a low salt diet (LSD; &lt; 0.1% NaCl + tap) or a high salt diet (HSD; 4% NaCl + 0.9% saline) for two weeks. We treated the groups with either IL16 specific antibodies or no antibody. After two weeks we measured mean arterial blood pressure (MAP), skin Na + , Cl - , and water content (rSKNa, rSKCl, rSKW), quantified lymphcapillary density, VEGF C and TonEBP expression. IL16 was specifically secreted from macrophages in response to hypertonicity in vitro . HSD increased skin electrolytes, activated TonEBP/VEGF C, and resulted in lymphcapillary hyperplasia. Anti IL16 treatment under LSD increased skin electrolyte, water content and MAP. The IL16 antibody blunted the VEGF C driven lymphcapillary response despite salt load. No differences in skin electrolytes and MAP were found between IL16 antibody treated and untreated mice after HSD. We conclude that IL16 is a regulator of electrolyte and water metabolism and MAP, even in the absence of HSD. The finding that the IL16 promoter contains a TonEBP binding site suggests that IL16 could act as an osmoprotective gene that is involved in regulation of electrolyte homeostasis and MAP control.

Interleukin-8 Content in the Stratum Corneum as an Indicator of the Severity of Inflammation in the Lesions of Atopic Dermatitis

Background: Atopic dermatitis (AD) is an inflammatory skin disease characterized by both acute and chronic eczema. Various markers are used to clinically evaluate the severity of AD. In order to identify a marker of local severity of AD, we measured IL-8, IL-18, vascular endothelial growth factor (VEGF), and transforming growth factor-α (TGF-α) levels in the stratum corneum (scIL-8, scIL-18, scVEGF and scTGF-α) and evaluated the correlation between the levels of these cytokines and the clinical severity scores of localized skin lesions. Methods: Stratum corneum samples were collected from the skin lesions of 50 patients with AD using the tape-stripping technique, and the scIL-8, scIL-18, scVEGF and scTGF-α levels were evaluated using the ELISA method. The trans-epidermal water loss and skin water content of the lesions were also measured prior to tape stripping. Results: The levels of scIL-8, scIL-18, scVEGF and scTGF-α were significantly higher in patients with AD than in healthy controls. Additionally, the levels of scIL-8, scIL-18 and scVEGF significantly correlated with the severity of AD. Conclusions: Among these cytokines, scIL-8 showed the highest correlation with the severity scores of lesions in AD as well as other parameters. Our results also suggest that measuring cytokines in the stratum corneum by using ELISA combined with tape stripping is a convenient method to evaluate the severity of skin lesions in AD.

The Effects of Different Relative Humidity with Low Temperature on Skin Physiology

People always experience different humidity and temperature in very short span of time. Therefore, people can adapt themselves to the changes of environment by their physiological changes. Many studies had showed that relative humidity (RH) affects thermal regulatory process. However, there is no related research showing the effects of different humidity with low temperature on skin physiology. The purpose of this study was to evaluate the effects of different RH with low temperature on skin physiology. Twenty subjects were selected for this study. All subjects stayed a chamber in 60% RH ands 24°C for 30minutes, and then moved to a chamber of 60% RH and 10°C on the first day. The second day, the combination of the chamber changed to 90% RH and 10°C. Skin temperature and skin water content were tested very minutes from the beginning to the 20th minute. The conclusions indicated that lower RH would induce lower skin temperature. Gender was not a factor to influence the skin temperature on different RH. Skin water content may not easily changed in a short span of time.