ATR-FTIR技术在面部敏感性皮肤角质层成分分析中的应用研究

【摘要】 目的 利用衰减全反射傅里叶变化红外光谱仪（ATR-FTIR）分析敏感性皮肤与正常皮肤角质层成分的差异,探讨该技术在敏感性皮肤发生机制研究中的应用价值。方法 自2018年12月至2019年2月,招募在上海市居住 ≥ 6年的148例志愿者,通过问卷调查、乳酸刺痛试验和辣椒素试验,将受试者分为正常皮肤组和敏感性皮肤组;同时,记录乳酸刺痛试验和辣椒素试验中受试者的总刺痛评分和总灼痛评分。应用ATR-FTIR检测角质层成分,包括天然保湿因子（NMF）、角质层脂质、游离脂肪酸（FFA）和β/α比值;同时应用其他无创技术测量经表皮失水率（TEWL）、角质层含水量、角质层脂质、皮肤pH值和3种周围感觉神经纤维的电流感觉阈值和浅表皮肤血流灌注量等皮肤生理参数。分析角质层成分与总刺痛评分和总灼痛评分的Spearman相关系数,以及与皮肤生理参数的Pearson相关系数。结果 73例志愿者完成全部试验,其中敏感性皮肤组34例,男15例,女19例,年龄（41.8 ± 8.9）岁;正常皮肤组39例,男19例,女20例,年龄（42.8 ± 9.4）岁。敏感性皮肤组和正常皮肤组角质层NMF分别为30.90 ± 7.38、37.01 ± 8.77（t = 3.193,P < 0.01）,FFA分别为14.90 ± 6.75和20.45 ± 11.76（t = 2.422,P < 0.05）,β/α值分别为3.17 ± 1.03和2.67 ± 0.56（t = -2.595,P < 0.05）,角质层脂质两组差异无统计学意义（t = 1.458,P > 0.05）。皮肤生理参数中,敏感性皮肤组TEWL显著高于正常皮肤组（t = -3.496,P < 0.001）,而5 Hz电流感觉阈值和表皮致密度显著低于正常皮肤组（P < 0.05）,角质层脂质差异无统计学意义（P > 0.05）。相关分析显示,NMF、FFA和β/α与TEWL（r值分别为-0.405、-0.562、0.503,均P < 0.01）和总刺痛评分（rs值分别为-0.401、-0.285、0.316,P < 0.01或0.05）均呈良好的相关性,同时,表皮致密度与NMF（r = 0.402,P < 0.01）和β/α比值（r = -0.369,P < 0.05）也呈良好的相关性。但NMF、FFA和β/α与角质层脂质、3种感觉神经纤维的电流感觉阈值、浅表皮肤血流灌注量及表皮厚度之间均无相关性（均P > 0.05）。结论 敏感性皮肤与正常皮肤角质层NMF、FFA和β/α存在显著差异,且NMF、FFA和β/α与部分角质层屏障功能生理参数之间具有良好的相关性。因此,ATR-FTIR是一种有效评价敏感性皮肤屏障功能的手段。     

银屑病患者皮肤屏障功能受损的研究

目的 探讨银屑病患者皮肤屏障功能受损的实验依据,以指导临床辅助治疗银屑病。方法 60例银屑病患者运用无创性皮肤生理功能测试仪检测皮损角质层含水量、皮脂含量及经表皮水分流失（TEWL）。电镜观察皮损处细胞超微结构,同时运用免疫组化方法检测皮损处酸性神经酰胺酶的表达。结果 与正常皮肤比较,银屑病皮损角质层含水量降低（P < 0.01）,TEWL值增加（P < 0.01）,皮脂含量差异无统计学意义。电镜下,皮损颗粒层角质形成细胞中板层小体数量较正常对照组减少,分布紊乱,体积大小不等;免疫组化染色显示酸性神经酰胺酶表达明显减少。结论 银屑病皮肤屏障功能明显受损,因此,恢复皮肤屏障功能,加强保湿是银屑病重要的辅助治疗手段之一。     

The keratin polypeptides of psoriatic epidermis

The polyacrylamide SDS electrophoretic pattern of protein extracted from the stratum corneum obtained by scraping the surface of involved skin of patients with psoriasis was different from that of uninvolved skin and normal controls. The pattern from superficial scales was similar to that of whole stratum corneum in the case of involved psoriatic epidermis but different in uninvolved and normal epidermis. These data indicate that the changes which are observed in the structural proteins during normal keratinization are not seen in involved psoriatic epidermis. In addition, the relative proportion of keratin polypeptides was different in involved psoriatic epidermis compared to normal skin. That these changes are not specific for psoriasis was shown by finding similar electrophoretic patterns with stratum corneum proteins from patients with other keratinizing disorders.     

Electrical measurement of moisturizing effect on skin hydration and barrier function in psoriasis patients

Transepidermal water loss (TEWL) in psoriatic skin lesions seems to be related to the severity of the psoriasis, and the electrical capacitance and conductance of the skin are indicators of the hydration level of the stratum corneum. We compared the characteristics of these electrical measurements, in assessing the persistent effect of a moisturizing cream on skin hydration and barrier function in psoriasis patients. Seventeen Korean psoriasis patients were recruited. Their right leg was treated with the moisturizer twice daily for 6 weeks, while their left leg was used as the control site. For each patient, one psoriatic plaque on each leg was selected as the involved psoriatic lesion. Uninvolved psoriatic skin was regarded as the apparently healthy looking skin 4-5 cm away from the periphery of the psoriatic lesion. The TEWL, electrical capacitance and conductance were measured, in order to evaluate the barrier function and hydration level of the stratum corneum. The clinical and biophysical data for each patient were recorded at the start of the study and after 2, 4 and 6 weeks. The degree of skin dryness at the applied area improved progressively. The electrical capacitance at the treated psoriatic lesion increased significantly after 2 weeks, and this improvement was maintained during the entire study period. However, no noticeable change was observed in the electrical conductance. The TEWL showed an inverse pattern to that of the skin capacitance, decreasing during the study period. The skin capacitance and TEWL exhibited good correlation with the visual assessment of skin dryness, but the skin conductance did not. Our data suggest that electrical capacitance and TEWL may be useful in the evaluation of the effect of a moisturizer on the hydration status and barrier function of psoriatic skin.     

Defective barrier function in melasma skin

Background Melasma is characterized by increased pigmentation and photodamaged features, which include solar elastosis. Recently, we detected the downregulation of the genes most associated with lipid metabolism using microarray analysis in melasma. These findings suggested that lesional skin may have different biophysical characteristics, and, in particular, an altered skin barrier function. Objective To determine the cutaneous biophysical characteristics of melasma. Methods The melanin index, erythema index, stratum corneum hydration, sebum content and transepidermal water loss (TEWL) were measured for lesional and perilesional normal skin of 16 melasma patients and then compared. In addition, a skin biopsy was performed on 11 of the 16 study subjects to measure stratum corneum thickness and to study the protein expressions of PPAR‐α and ALOX15B. Results Melanin index, erythema index and stratum corneum hydration were significantly higher in lesional skin than in perilesional normal skin. No significant difference was found between lesional and normal skin in terms of basal TEWL level or sebum content. However, the rate of TEWL after barrier perturbation was significantly higher for lesional skin, and the barrier recovery rate was significantly delayed. Furthermore, a trend towards thinned stratum corneum was observed for lesional skin, and this was correlated with barrier recovery rate. The expressions of PPAR‐α and ALOX15B were variable in the samples. Conclusions Melasma skin is characterized by impaired stratum corneum integrity and a delayed barrier recovery rate.     

Evaluation of skin surface hydration in Korean psoriasis patients: a possible factor influencing psoriasis

Psoriasis is recognized as a chronic, relapsing disorder of the skin, and its clinical course is influenced by various environmental factors. However, only a few articles have addressed the effect of low epidermal hydration status as an exacerbating factor of psoriasis. Our study was performed to investigate the relationship between subjective assessment and quantified data regarding dryness parameters in psoriasis patients. Seventy psoriasis patients were enrolled in our study. Subjective assessments were undertaken by evaluating the extent of involvement, erythema, scale and infiltration of individual lesions. Functional status of stratum corneum was evaluated by measuring electrical capacitance and conductance of the lesional and uninvolved skin of psoriatic patients. In addition, measurement of trans-epidermal water loss was performed. The results showed poor hydration status and barrier function in involved psoriatic epidermis compared with the uninvolved skin. Subjective assessment showed fairly good correlation with the quantified values. In conclusion, the degree of dryness in psoriatic skin lesions--which we presume to be one of the aggravating factors of psoriasis--seemed to be related to disease severity.     

Elevated phosphorus in psoriatic skin determined by energy dispersive x-ray micro-analysis

Scanning electron-microscopy in combination with secondary electron imaging and x-ray energy spetrometry (electron-probe micro-analysis) was performed on the stratum corneum of involved and uninvolved, psoriatic skin. The significant, elemental alterations included an increase in phosphorus and calcium in the involved skin regions. A composite, chemical, elemental profile of normal and uninvolved, psoriatic stratum corneum is presented.     

Effect of skin pH for wrinkle formation on Asian: Korean,Vietnamese and Singaporean

Background Skin pH may be influenced by various factors, such as hydration of stratum corneum, rate of sebum excretion rate, transepidermal water loss (TEWL) and sweating in relation to skin ageing. Objective The aim of this study was to evaluate the correlation between skin pH and wrinkle formation that is directly related to ageing. In addition, we investigated the factors related to skin ageing by comparing the association between skin pH and other skin properties. Methods Three hundred volunteers were selected from three countries: Korea, Vietnam and Singapore. Hydration on the stratum corneum, the rate of sebum excretion rate, melanin index, TEWL and skin temperature on the cheek were measured in a controlled room, and wrinkle length and depth using replicas were compared with skin pH variation. Results The mean and standard deviation of skin surface pH among the three countries were 5.510 ± 0.625. The greatest gap of skin pH that revealed significant differences for skin properties was represented between the Koreans and the Vietnamese. For all three countries, skin hydration, melanin contents, wrinkle length, wrinkle depth and skin temperature were significantly correlated with skin pH. Factors related to skin moisturizing, such as skin hydration, sebum excretion rate and skin temperature, were negatively correlated with skin pH. Wrinkle length and depth decreased as skin pH became more acidic. Conclusions Skin properties displayed various values depending on skin pH. In particular, wrinkle formation significantly decreased as skin pH becomes more acidic. We conclude that skin pH is determined by skin properties, such as skin hydration, sebum excretion rate, melanin concentration, TEWL and skin temperature that affects wrinkle formation.     

The relationship of transepidermal water loss to skin temperature in psoriasis and eczema.

Transepidermal water losses (TEWL) from psoriatic and eczematous skin were measured while skin temperature was varied between 29 degrees C and 37 degrees C. The relationship of TEWL to skin temperature in these diseases is different from that obtaining in normal skin. These differences are thought to be due to the altered filtration properties of diseased stratum corneum. Formulae were devised to allow TEWL rates in psoriasis and eczema to be expressed at a standard temperature for comparative purposes.     

X-ray microanalysis of psoriatic skin

Electron probe x-ray microanalysis was used to study elemental distribution in uninvolved and involved skin from patients with psoriasis, and in skin from healthy controls. Significant differences were found between the involved and uninvolved psoriatic skin. In the involved skin, the concentrations of Mg, P, and K were higher in the stratum germinativum, spinosum, and granulosum, compared to the corresponding strata in uninvolved skin. Neither involved nor uninvolved psoriatic stratum germinativum differed markedly from nonpsoriatic control stratum germinativum. In uninvolved psoriatic skin only a lower level of K was noted. In comparison to uninvolved psoriatic skin, the elemental composition of the various strata of involved psoriatic skin shows a pattern typical for highly proliferative, nonneoplastic cells.     

Developmental alterations of physical properties and components of neonatal-infantile stratum corneum of upper thighs and diaper-covered buttocks during the 1st year of life

BackgroundAlthough physical properties of neonatal-infantile stratum corneum (SC) change drastically after birth, precise developmental alterations of specific sites have not been fully elucidated.ObjectiveTo determine the longitudinal alterations of neonatal-infantile SC functions and components of upper thighs and diaper-covered buttocks during the first year of life. The data were compared with those of adults.MethodsNineteen full-term neonates and their mothers were subjected to the measurements. Skin hydration, water sorption/retention capacity, TEWL were measured. Superficial SC analyses for NMF, ester binding sebum, and free fatty acids were performed by ATR-FTIR spectrometer. Total amount of ceramides (CERs) and CER subclasses were analyzed by NPLC-ESI-MS.ResultsSC hydration of neonatal thighs was lower than that of their mothers, which rapidly increased during the 1st month. Skin hydration of neonatal buttocks was similar to that of their mothers. This also rapidly increased during the 1st month. The neonatal TEWL was less than those of their mothers indicating more efficient barrier function at both sites, which significantly increased during the 1st year development. This was mostly correlated decreased in the ω-hydroxy fatty acid-esterified CERs. Superficial ester-binding sebum content of neonates was similar to that of their mothers, which significantly decreased during the measurement; the decrease was more marked on buttocks. Neither NMF nor FFA of the superficial SC showed significant alteration during the 1-year development.ConclusionOur results indicate that physical functions and components of neonatal-infantile SC show considerable alterations between diaper-covered buttocks and upper thighs during the 1st year development.     

【开放获取】皮肤干燥是通透屏障功能受损的表现吗？

【摘要】 有学者认为,皮肤干燥是表皮通透屏障功能受损的表现,但目前尚没有足够的证据证明这一观点。实际上,皮肤干燥是角质层含水量降低的表现。角质层含水量主要由角质层天然保湿因子的量决定,而表皮通透屏障功能则主要由角质层脂质的质和量以及结构蛋白决定。如果皮肤干燥是由表皮通透屏障功能降低所致,那么,角质层含水量应当与透皮失水率呈负相关性。但是研究表明,无论是正常人皮肤、鱼鳞病皮损或皮脂腺缺乏的小鼠皮肤,角质层含水量与透皮失水率均无负相关性。相反,有研究显示,人角质层含水量与透皮失水率呈正相关性。因此,皮肤干燥似乎不是表皮通透屏障功能受损的表现。     

Altered [125I]epidermal growth factor binding and receptor distribution in psoriasis

Stimulation of growth and differentiation of human epidermis by epidermal growth factor (EGF) is mediated by its binding to specific receptors. Whether EGF receptors primarily mediate cell division or differentiation in hyperproliferative disease such as psoriasis vulgaris is unclear. To study the pathogenesis of psoriasis, 4-mm2 punch biopsy specimens of normal, uninvolved, and involved psoriatic skin were assayed for EGF receptors by autoradiographic, immunohistochemical, and biochemical methods. Using autoradiographic and immunohistochemical methods, basal keratinocytes were found to contain the greatest number of EGF binding sites and immunoreactive receptors as compared to the upper layers of the epidermis in both normal epidermis and psoriatic skin. No EGF receptor differences between normal and psoriatic epidermis were observed in this layer. In the upper layers of the epidermis, a 2-fold increase in EGF binding capacity was observed in psoriatic skin as compared with normal thin or thick skin. Biochemical methods indicated that [125I]EGF binding was increased in psoriatic epidermis as compared with similar thickness normal epidermis when measured on a protein basis. Epidermal growth factor was shown to increase phosphorylation of the EGF receptor in skin. EGF receptors retained in the nonmitotic stratum spinosum and parakeratotic stratum corneum may reflect the incomplete, abnormal differentiation that occurs in active psoriatic lesions. Alternatively, retained EGF receptors may play a direct role in inhibiting cellular differentiation in the suprabasal layers.     

Biophysical characteristics of skin in diabetes: a controlled study

Background  Cutaneous complications are common in diabetes. Previous assays suggest that hyperglycemia and decreased insulin signal are involved in the impairment of skin function. The aim of this study was to evaluate the biophysical characteristics of skin in patients with diabetes mellitus and compares them with healthy non-diabetic controls.
Objective  To measure biophysical characteristic of skin including transepidermal water loss (TEWL), water content, sebum and skin elasticity in patients with diabetes mellitus and compare them with healthy non-diabetic controls.
Methods  This case-control study was conducted on 38 patients with diabetes and 40 age- and sex-matched healthy people. The biophysical properties of skin including stratum corneum (SC) hydration, sebum content, TEWL and skin elasticity were measured and compared between the two groups at three different locations of the body.
Results  The measurement of SC hydration and TEWL showed no significant difference between diabetics and controls. The skin surface lipids on the forehead but not other sites were significantly lower in the diabetics than in the controls. Acoustic wave propagation speed, a measurement related to skin elasticity, was significantly lower in forearm and forehead of diabetics.
Conclusion  Diabetes affects some functional properties of epidermis and dermis that may responsible for many cutaneous manifestations of diabetes. These results suggest that patients with diabetes mellitus tend to show a normal hydration state of the SC together with decreased sebaceous gland activity and impaired skin elasticity, without any impairment of the SC barrier function.

Conflicts of interest

None declared     

comparison between DNA synthesis and mitosis in uninvolved and involved psoriatic epidermis and normal epidermis

Biopsies have been taken from the involved and uninvolved skin of eleven patients with psoriasis and the normal skin of six patients without psoriasis, 1 h after in vivo injection of 10 μCi of ³H-thymidine. Mitotic counts and counts of labelled cells (synesizing DNA) after autoradiography have been carried out. The ratio of mitoses to labelled cells was 1: 25 in clinical psoriasis, 1: 190 in uninvolved psoriatic epidermis and 1: 450 in normal epidermis. The number of labelled cells in clinical psoriasis was approximately 12 times greater than normal epidermis. However, the number of labelled cells in uninvolved psoriatic epidermis was approximately twice that of normal. These results imply an alteration in the components of the cell cycle in both involved and uninvolved psoriatic epidermis.     

Changes in Transepidermal Water Loss and Skin Hydration according to Expression of Aquaporin-3 in Psoriasis

Background

Aquaporins (AQPs) are a family of water transporting proteins present in many mammalian epithelial and endothelial cell types. Among the AQPs, AQP3 is known to be a water/glycerol transporter expressed in human skin.

Objective

The relationship between the expression level of AQP3 and transpidermal water loss (TEWL) in the lesional and peri-lesional skin of psoriasis-affected patients, and skin hydration in the lesional and peri-lesional skin of psoriasis patients, was investigated.

Methods

The expression of AQP3 in psoriasis-affected and healthy control skin was determined using immunohistochemical and immunofluroscence staining. TEWL and skin hydration were measured using a Tewameter® TM210 (Courage & Khazaka, Cologne, Germany) and a Corneometer® CM 820 (Courage & Khazaka), respectively.

Results

AQP3 was mainly expressed in the plasma membrane of stratum corneum and the stratum spinosum in normal epidermis. Unlike the normal epidermis, AQP3 showed decreased expression in the lesional and peri-lesional epidermis of psoriasis. TEWL was increased, and skin hydration was decreased, in the lesional and peri-lesional skin of psoriasis patients, compared with the healthy control sample.

Conclusion

Although various factors contribute to reduced skin hydration in the lesional and peri-lesional skin of psoriasis, AQP3 appears to be a key factor in the skin dehydration of psoriasis-affected skin.     

SDS-PAGE analysis of whole and fractionated psoriatic epidermis

The SDS-PAGE patterns of keratinous proteins extracted from whole epidermis and fractionated epidermal cells were studied. Those from the whole and fractionated epidermal cells of psoriatic involved skin showed an extra 58,000 dalton polypeptide in addition to the four major polypeptides (M.W.: 67,000, 63,000, 59,000 and 55,000) which were demonstrated to be common to normal epidermis and psoriatic-uninvolved epidermis. The stratum corneum of psoriatic involved skin did not contain a 67,000 dalton polypeptide which was present in the stratum corneum of normal and psoriatic uninvolved skin. The presence of the additional 58,000 dalton polypeptide may be due to abnormal synthesis of keratin proteins in the psoriatic epidermis, since this additional polypeptide was present in the lower living layers of the psoriatic epidermis as well. On the other hand, the absence of the 67,000 dalton polypeptide in the psoriatic stratum corneum may be due to enzymatic modifications during the transition from the living cell layers to the horny layer.     

Interrelationship between water-barrier and reservoir functions of pathologic stratum corneum

Scaly skin lesions are caused by decreased water content of the stratum corneum, despite the well-known fact that they usually show increased water passage. By performing simultaneous measurements of transepidermal water loss (TEWL) to check the water-barrier function of the stratum corneum and cutaneous conductance to the high-frequency electric current of 3.5 MHz, which is an indicator of skin-surface hydration state, in patients with psoriasis who had lesions of various grades of severity, we obtained data indicating that there is an inverse relationship between these functions of the stratum corneum. Furthermore, a time course study of TEWL and functional analysis of stratum corneum by an in vivo water sorption-desorption test performed on the experimentally induced scaly lesions after adhesive-tape stripping demonstrated that such pathologic stratum corneum is characterized by a water-holding defect that is associated with increased TEWL.