特应性皮炎患儿与健康儿童皮肤屏障功能的对比

目的探讨特应性皮炎(AD)患儿与健康儿童皮肤屏障功能的差异。方法 0～7岁的AD患儿和健康儿童各60名,根据不同年龄段分成2组,0～2岁组和2～7岁组各30例。依次进行角质层含水量、pH值、经表皮水分丢失量(TEWL)的测量,使用SPSS13.0统计软件分析。结果 0～2岁、2～7岁AD患儿与健康儿童比较,角质层含水量除前臂无差异外,前额和颊前均明显低于健康对照组;皮肤表面pH值均明显高于健康对照组;0～2岁的AD患儿TEWL值除前臂无差异外,前额和颊前均明显高于健康对照组,而2～7岁AD患儿TEWL值均明显高于健康对照组。结论 AD患儿与健康儿童比较,皮肤屏障功能存在障碍。表现为角质层含水量、皮肤表面pH值、TEWL值有不同程度的差异。     

健康儿童皮肤透皮失水率与角质层含水量的相关性研究

目的探讨角质层含水量与透皮失水率的相关性。方法 2021年10月至2022年6月在普宁市公共健康医疗中心、2所幼儿园及2所小学招募≤ 17岁健康儿童。用皮肤生理功能测量仪测量健康儿童左前臂屈侧和右胫前部位的透皮失水率和角质层含水量, 采用Pearson相关分析法分析不同年龄、性别儿童的透皮失水率与角质层含水量的相关性。结果共招募1 396例健康儿童, 年龄1个月至17岁, 男783例、女613例。在1 ～ < 12个月组, 除男童前臂部位的皮肤透皮失水率与角质层含水量无显著相关性外, 男童胫前和女童前臂及胫前部位的透皮失水率与角质层含水量均呈正相关(r值为0.283、0.404、0.420, 均P < 0.05);在1 ～ 2岁组, 男童前臂和女童胫前部位的皮肤透皮失水率与角质层含水量无显著相关性, 而男童胫前和女童前臂部位的透皮失水率与角质层含水量均呈正相关(r值为0.370、0.419, 均P < 0.01);在3 ～ 5岁组和6 ～ 11岁组, 除6 ～ 11岁组男童胫前的透皮失水率与角质层含水量无显著相关性外, 两组男女性其他部位的透皮失水率与角质层含水量均呈...     

Functional analyses of the eyelid skin constituting the most soft and smooth area on the face: contribution of its remarkably large superficial corneocytes to effective water-holding capacity of the stratum corneum

BACKGROUND/PURPOSE: The eyelid constitutes a unique area on the face because of its soft, smooth and thin skin distinct from that of other facial portions. Its softness facilitates their easy compliance to blinking movement, which is indispensable to protect the wet surface of the eyeball. Moreover, the skin of the eyelid does not show any prominent follicular orifices or an oily appearance even in adults. Despite such uniqueness, its biophysical characteristics have remained unclear as compared with other facial skin. METHODS: We conducted non-invasive instrumental measurements on the skin of the upper eyelid of 22 healthy Japanese adults in comparison with those of the adjacent facial skin, i.e. the cheek and nose. Additionally, we examined 10 adult patients with atopic dermatitis (AD) whose facial skin remained clinically free from skin lesions for at least 2 months. RESULTS: The eyelid skin showed high transepidermal water loss like other facial skin. Its skin surface hydration state was as high as that of the adjacent skin, despite the fact that the eyelid skin revealed extremely low amounts of surface lipids unlike its neighboring skin regions. However, in contrast to small corneocytes found in other facial areas, the corneocytes of the eyelid skin displayed a significantly larger surface size, suggesting that slow turnover of its stratum corneum (SC) takes place to allow sufficient maturation of the corneocytes, enabling them to exert efficient water-binding capacity. Its pH tended to be higher than that of the adjacent skin. Its superficial blood flow was significantly higher than that of others, although skin color assessment showed lower color values for redness than those of the other facial skin sites. In clinically non-lesional skin of adult AD patients, we found increased blood circulation and a higher parameter for redness, suggesting the presence of invisible mild inflammation in the dermis even long after subsidence of visible inflammatory changes. CONCLUSION: Our present biophysical findings suggest that, although the eyelid skin is poor in surface lipids, its extraordinary large superficial corneocytes play an important role in maintaining sufficient hydration state of its skin surface to keep it soft and flexible, enabling its good compliance with the blinking movement.     

Comparison of skin barrier function and sensory nerve electric current perception threshold between IgE-high extrinsic and IgE-normal intrinsic types of atopic dermatitis

Background  Two types of atopic dermatitis (AD) have been proposed, with different pathophysiological mechanisms underlying this seemingly heterogeneous disorder. The extrinsic type shows high IgE levels presumably as a consequence of skin barrier damage and feasible allergen permeation, whereas the intrinsic type exhibits normal IgE levels and is not mediated by allergen-specific IgE.
Objectives  To investigate the relationship between pruritus perception threshold and skin barrier function of patients with AD in a comparison between the extrinsic and intrinsic types.
Methods  Enrolled in this study were 32 patients with extrinsic AD, 17 with intrinsic AD and 24 healthy individuals. The barrier function of the stratum corneum was assessed by skin surface hydration and transepidermal water loss (TEWL), and pruritus perception was evaluated by the electric current perception threshold (CPT) of sensory nerves upon neuroselective transcutaneous electric stimulation.
Results  Skin surface hydration was significantly lower and TEWL was significantly higher in extrinsic AD than intrinsic AD or normal controls. Although there was no statistically significant difference in CPT among extrinsic AD, intrinsic AD and normal controls, CPT was significantly correlated with skin surface hydration and inversely with TEWL in intrinsic AD and normal controls, but not extrinsic AD. Finally, CPT was correlated with the visual analogue scale of itch in the nonlesional skin of patients with extrinsic but not intrinsic AD.
Conclusions  Patients with extrinsic AD have an impaired barrier, which increases the pre-existing pruritus but rather decreases sensitivity to external stimuli. In contrast, patients with intrinsic AD retain a normal barrier function and sensory reactivity to external pruritic stimuli.     

Stratum corneum lipid profile and maturation pattern of corneocytes in the outermost layer of fresh scars: the presence of immature corneocytes plays a much more important role in the barrier dysfunction than do changes in intercellular lipids

BACKGROUND: The functional characteristics of the stratum corneum (SC) of fresh scars as well as keloids and hypertrophic scars are characterized by elevated transepidermal water loss (TEWL) and increased SC hydration. OBJECTIVES: To study the composition of the intercellular lipids and maturation properties of the cornified envelope (CE) of the SC, as these are the most important components for the SC barrier function in fresh scars. METHODS: SC lipids were extracted from the donor site for split-thickness skin grafting soon after re-epithelialization using a cup method, and were analysed with high-performance thin-layer chromatography. CEs, which were prepared from superficial layers of the SC, were double stained with Nile red and anti-involucrin. RESULTS: We found a significant decrease in the proportion of ceramide (CER) in the SC lipids of fresh scars. We also observed changes in the SC CER profile that consisted of an increase in CER 4 and CER 7 and a decrease in CER 3, without any significant change in the proportion of CER 1. These changes were insufficient to explain the remarkably high TEWL recorded in the early stage of fresh scars. In contrast, with double staining of CE with Nile red and anti-involucrin, we detected the presence of numerous immature and less hydrophobic corneocytes in the outermost layer of the SC of fresh scars. Scanning electron microscopy of such corneocytes revealed numerous fine wrinkles on their enlarged surface area. Most of all, we found a closely similar, time-dependent, exponential decrease in the ratio of immature corneocytes with a poorly hydrophobic CE and in the recorded TEWL values in fresh scars. There was a highly significant positive correlation between the proportion of immature corneocytes in the outermost layer of the SC and TEWL values. CONCLUSIONS: These results suggest that the SC barrier dysfunction of the fresh scars is attributable to the presence of immature corneocytes with a less hydrophobic CE, rather than to the changes in SC lipid composition.     

Correlation between the properties of the lipid matrix and the degrees of integrity and cohesion in healthy human Stratum corneum

The correlation between the degrees of integrity and cohesion in healthy human Stratum corneum (SC) and the properties of the SC lipid matrix could be examined non-invasively in vivo using ATR-FTIR spectroscopy and measurements of pH, conductance, and transepidermal water loss (TEWL) taken in the course of tape-stripping. The change of TEWL following the removal of a SC layer with a predefined thickness served as a measure for the SC integrity, and the amount of protein removed by predefined number of tapes - as a measure for the SC cohesion. The extent of lipids organized in orthorhombic lattices and the pH in the inner SC emerged as the main factors that determine the degree of integrity. The amounts and molecular organization of the SC lipids did not correlate with the degree of cohesion, while the pH and the hydration of SC correlated well with the degree of cohesion in the superficial but not in the inner SC layers. This study evidenced the variability of SC integrity and cohesion existing in healthy human skin, demonstrated the importance of the lipid molecular organization for the SC integrity, and illustrated the limitations in the determination the degree of corneodesmolysis in SC based only on the protein content of tape-strips.     

Decreased hydration state of the stratum corneum and reduced amino acid content of the skin surface in patients with seasonal allergic rhinitis

Recent studies of the stratum corneum (SC) in patients with atopic dermatitis (AD) have disclosed various functional impairments even in clinically unaffected skin. However, it has not been clear whether the presence of atopic background itself has any influence on the function of the SC. In this study, we conducted functional studies of the SC in the mid-portion of the flexor surface of the forearm of 49 skin lesion-free patients with allergic rhinitis to Japanese cedar pollen (atopic respiratory disease; ARD) in early spring, their disease-active season, by comparing the findings obtained with those in 28 patients with AD and 57 age-matched healthy control subjects. The results showed that the patients with ARD had significantly lower skin surface hydration levels assessed by high-frequency conductometry than those of the healthy control subjects. These levels were, however, not as low as those noted in moderately or severely affected patients with AD. Moreover, by measuring the amounts of water-soluble amino acids contained in the superficial portions of the SC, we found that these are also decreased at a marginal level ( P  = 0.051) in patients with ARD compared with levels in healthy control subjects. In contrast, the water barrier function of the SC evaluated by measurements of transepidermal water loss in patients with ARD was not different from that of the healthy control subjects. These results suggest that, although their skin appears normal clinically, the SC of the patients with ARD has functional deficiency in water-holding capacity.     

Normal recovery of the stratum corneum barrier function following damage induced by tape stripping in patients with atopic dermatitis

Patients with atopic dermatitis (AD) constantly inflict mechanical damage to their skin by scratching induced by pruritus. On excoriated lesions of the cheek we found exceedingly high levels of transepidermal water loss (TEWL) as compared to those in the normal skin of healthy subjects. However, it is not clear whether the skin of patients with AD also shows an abnormally slow recovery after mechanical damage. We compared the recovery of the barrier function of the stratum corneum (SC). after its complete removal by tape stripping, in patients with AD and age-matched healthy control subjects. On the normal-looking skin of the flexor forearm, we found no difference in the recovery process of the water barrier function of the SC between the two groups. This suggests that ability to reconstruct SC barrier function after mechanical damage is not impaired in AD patients.     

Functional analysis of the stratum corneum of scalp skin: studies in patients with alopecia areata and androgenetic alopecia

Abstract Because of the presence of thick long hairs on the scalp, little information is available concerning the functional characteristics of the stratum corneum (SC) of scalp skin. We therefore conducted a functional study of the SC of lesional scalp skin of patients with alopecia areata and of patients with androgenetic alopecia. We compared the scalp with the cheek and the flexor surface of the forearm (volar forearm). The water barrier function of the scalp SC of both patient groups, in terms of transepidermal water loss (TEWL), was almost comparable to that of the volar forearm, and was far better than that of facial skin. However, hydration of the scalp skin surface, as evaluated by measurement of high-frequency conductance, was markedly higher than that of facial skin, and showed significantly higher values than the volar forearm. These characteristics seem to be dependent, at least to some extent, on the amount of sebum-derived skin surface lipids because these were abundant on the scalp skin. Moreover, removal of skin surface lipids led to a significant decrease in skin surface hydration. The superficial corneocytes, the size of which reflects the proliferative activity of the epidermis, were substantially smaller on the scalp than on the volar forearm but significantly larger than on the cheek. These findings suggest that the rate of turnover of the scalp epidermis is intermediate between that of the facial and volar forearm epidermis. We conclude that the SC of the scalp skin in humans is functionally distinct from that of the face and extremities. Received: 6 January 2000 / Revised: 11 August 2000 / Accepted: 25 September 2000     

Clinical severity correlates with impaired barrier in filaggrin-related eczema

Mutations in the gene-encoding filaggrin (FLG), a key molecule involved in skin barrier function, have been shown to be a major predisposing factor for atopic dermatitis (AD; eczema). To elucidate the pathomechanisms underlying filaggrin-related AD, we investigated stratum corneum (SC) hydration and transepidermal water loss (TEWL) as parameters of barrier function in AD patients harboring FLG mutations compared to AD patients without any FLG mutation. In filaggrin-related AD, SC hydration was both significantly reduced (P<0.01-0.05) and thicker (P<0.01-0.05) than that in healthy controls. TEWL was demonstrably increased in non-filaggrin AD compared to healthy controls (P<0.01-0.05). The objective score of atopic dermatitis (OSCORAD), a disease clinical severity index, significantly correlated with TEWL (r=0.81, P<0.005), SC hydration (r=-0.65, P<0.05), and SC thickness (r=0.59, P<0.05) in filaggrin-related AD. On the contrary, there was no correlation between these parameters and the OSCORAD in non-filaggrin AD. Furthermore, a significant correlation was obtained between the OSCORAD and specific IgE for house dust (r=0.66, P<0.05), mite allergen (r=0.53, P<0.05), and cat dander (r=0.64, P<0.05) in filaggrin-related AD, but not in non-filaggrin AD. All these data suggest that experimentally demonstrable skin barrier defects due to FLG mutations may play a crucial role in the pathogenesis of AD.     

Percutaneous penetration of sodium lauryl sulphate is increased in uninvolved skin of patients with atopic dermatitis compared with control subjects

BACKGROUND: Involved regions of the skin in patients with atopic dermatitis (AD) have been shown to have higher transepidermal water loss (TEWL), indicating a compromised skin barrier. Whether uninvolved skin also has diminished barrier characteristics is controversial. OBJECTIVES: To study the penetration of sodium lauryl sulphate (SLS) into uninvolved skin of patients with AD compared with the skin of control subjects. METHODS: Percutaneous penetration was assessed using the tape stripping technique on the stratum corneum (SC). Twenty patients with AD and 20 healthy subjects were exposed to 1% SLS for 4 h on the mid-volar forearm. After the end of exposure the SC was removed by adhesive tape. The amount of SLS was determined in each consecutive strip. Fick's second law of diffusion was used to deduce the diffusivity and the partition coefficient of SLS between water and the SC. RESULTS: The SC thickness was similar in both groups; however, the TEWL was higher in patients with AD compared with that of the control group (mean+/-SD 8.4+/-4.3 and 6.3+/-2.0 g m-2 h-1, respectively). There was a correlation between SC thickness and TEWL in control subjects but no correlation was found in patients with AD. The diffusivity of SLS through uninvolved AD skin was higher compared with normal skin (mean+/-SD 12.7+/-5.8x10(-9) and 6.2+/-3.0x10(-9) cm-2 h-1, respectively), while the partition coefficient between SC and water was lower (mean+/-SD 137+/-64 and 196+/-107, respectively). CONCLUSIONS: The results show a different penetration profile of SLS into the SC of patients with AD compared with control subjects. This indicates that even noninvolved skin in patients with AD has altered barrier characteristics, emphasizing the importance of skin protection and prevention of skin contact with chemicals.     

Noninvasive biophysical assessments of the efficacy of a moisturizing cosmetic cream base for patients with atopic dermatitis during different seasons

BACKGROUND: The use of emollients is recommended for patients with atopic dermatitis (AD) to maintain improved condition. OBJECTIVES: To ascertain objectively the effectiveness of a moisturizing cream for patients with AD during different seasons. METHODS: We conducted clinical evaluations, noninvasive biophysical measurements and biochemical analyses of the stratum corneum (SC) components of the volar forearm skin of 23 patients with AD after a moisturizer was applied twice daily for 4 weeks. The moisturizer was formulated according to the consensus of cosmetic scientists belonging to major Japanese cosmetic companies. The nontreated forearm served as a control. RESULTS: After using the moisturizer treatment, the hydration of the SC significantly increased together with a decrease in the desquamation measurements and an improvement in the regularity of skin surface corneocytes. An improvement was observed in the SC barrier function in winter, but was achieved only after 4 weeks in late spring during which time there even occurred exacerbation of skin conditions in three patients. With use of the moisturizer treatment, we found no change in the SC content of free amino acids or ceramides, the ratio of interleukin (IL)-1 receptor antagonist to IL-1alpha, the ratio of immature to mature cornified envelopes, the size of the corneocytes or the emergence of parakeratotic cells in the skin surface corneocytes. CONCLUSION: Treatment with an adequate moisturizer is beneficial for the dry skin of patients with AD during the dry, cold season but it does not influence the impaired SC barrier function as effectively in the less arid season.     

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     

Skin irritation due to repetitive application of adhesive tape: the influence of adhesive strength and seasonal variability

BACKGROUND/PURPOSE: Influence of the repetitive application of pressure-sensitive adhesive tapes on skin was evaluated. METHODS: Two kinds of tapes with different adhesive strengths were repetitively applied to the inside of the forearm of six volunteers in winter and summer, in order to examine the dermal peeling force, the amount of stripped corneocytes, transepidermal water loss (TEWL), hydration and deepened skin furrows (changes in skin surface topography) in the epidermal stratum corneum. RESULTS AND CONCLUSION: As adhesive tapes were applied repetitively, dermal peeling force gradually increased while the amount of stripped corneocytes decreased. As the cumulative amount of stripped corneocytes increased with repetitive applications, the skin irritation worsened as measured by increased destruction of the skin surface topography and TEWL. These phenomena were more marked with the stronger adhesive tape, and there was seasonal variability.     

Effects of skin moisturizer on the skin barrier dysfunction model: An evaluation of the heel via tape-stripping in healthy,young adults

BackgroundThis study seeks to establish the skin barrier dysfunction model at the heel via tape-stripping (TS) by evaluating the skin moisturizing effects.Materials and methodsNineteen young, female participated in the study. A sequence of TS was performed at the heel and trans-epidermal water loss (TEWL), stratum corneum (SC) hydration, and surface pH were measured. Following TS, the subjects were divided into three groups: moisturizer, emollient, and overcoat. These agents were applied daily at night, and the skin parameters were measured the next morning for a week.ResultsThe TEWL value of TS immediately and 5 min after TS were significantly higher than what was obtained before TS, while the SC hydration after TS was significantly lower than what was obtained before TS. However, there were no significant differences in the skin parameters among the three agents on day 7 after application, with the two-way ANOVA showing no interaction among the agents and number of days.ConclusionThe skin barrier dysfunction model at the heel was established by TS in healthy, young adults. However, the physiological function of the skin at the heel did not change drastically and showed no differences even after continuous application for 7 days.     

The Effect of Gromwell (Lithospermum erythrorhizon) Extract on the Stratum Corneum Hydration and Ceramides Content in Atopic Dermatitis Patients

Background

A disruption of the balance between the water content of the stratum corneum (SC) and skin surface lipids may lead to the clinical manifestation of dryness of skin in patients with atopic dermatitis (AD).

Objective

To determine whether supplementation of gromwell (Lithospermum erythrorhizon), one of herbs used in East Asia in remedies for various abnormal skin conditions, may improve the SC level of hydration and ceramides, major lipid in SC in patients with AD.

Methods

A total of 28 subjects with AD were randomly assigned into two groups: either gromwell group received dextrose contained capsules with 1.5 g of gromwell extracts or placebo group received only dextrose contained capsules for 10 weeks.

Results

In contrast to no alteration of SC hydration and ceramides in placebo group, the SC hydration in gromwell group was significantly increased in parallel with an increase of SC ceramides. Furthermore, % increase of SC hydration in gromwell group bore a positive correlation with the clinical severity, which suggests that the increase of SC hydration in gromwell group was more effective as AD was more severe.

Conclusion

Supplementation of gromwell improves SC hydration in parallel with an increase of ceramides in part.     

Increased stratum corneum serine protease activity in acute eczematous atopic skin

Background Atopic dermatitis (AD) is a chronic inflammatory disease associated with changes in stratum corneum (SC) structure and function. The breakdown of epidermal barrier function in AD is associated with changes in corneocyte size and maturation, desquamation, lipid profiles, and some protease activities. Objectives The purpose of this study was: (i) to examine physiological changes in lesional (L) skin of acute eczematous AD, compared with nonlesional (NL) AD skin and healthy (H) skin, using sequential tewametry and SC protein analysis to estimate SC thickness; and (ii) to assess which serine proteases might be involved in pathogenesis. Methods Six subjects with H skin, six AD patients with NL skin and six AD patients with mild to moderate eczema (L skin) were enrolled. Skin was assessed using several noninvasive techniques but SC thickness was estimated using tewametry and SC protein content of D‐Squame strippings. SC integrity was determined by sequential tape stripping (D‐Squame) and infrared densitometry. Kallikreins, plasmin, urokinase and leucocyte elastase protease activities together with a novel SC tryptase‐like enzyme activity were quantified. Results Transepidermal water loss (TEWL) levels after D‐Squame stripping were elevated in L compared with NL and H skin at all sampling points (P < 0·05). Conversely, the amount of SC removed by sequential tape stripping was decreased in L skin, indicating increased intracorneocyte cohesion (P < 0·05). By correlating 1/TEWL values and SC removed as an estimate of SC thickness, a significantly thinner SC was observed in L compared with NL and H skin (P < 0·05). Elevated extractable serine protease activity was measured in AD skin in the order: SC tryptase‐like enzyme (45×), plasmin (30×), urokinase (7·1×), trypsin‐like kallikreins (5·8×) and chymotrypsin‐like kallikreins (3·9×). Leucocyte elastase activity was not detected in H and NL skin but was observed in AD SC samples (L skin). All enzymes were elevated in the deeper layers of L SC compared with NL and H SC samples. All consistently elevated SC protease activities were significantly correlated with the bioinstrumental data. Conclusions We report increased serine protease activities in acute eczematous AD, especially in deeper layers of the SC, including SC tryptase‐like enzyme, plasmin, urokinase and leucocyte elastase activities. These elevations in protease activities were associated with impaired barrier function, irritation, and reduced skin capacitance. Increased SC cohesion was apparent despite elevated TEWL during tape stripping, which would indicate reduced SC thickness in acute eczematous lesions of AD. Indeed, this was observed using an estimate of SC thickness.     

Functional assessment of the stratum corneum under the influence of oral aromatic retinoid (etretinate) in guinea-pigs and humans. Comparison with topical retinoic acid treatment

Clinically we have noted that the skin of patients treated with long-term oral etretinate becomes uniformly soft and smooth to touch, like facial skin that becomes smoother and less wrinkled following treatment with topical tretinoin. This suggests that retinoids, whether used systemically or topically, alter the physical properties of the skin, particularly of the stratum corneum (SC). To study the influence of retinoids on the SC, we serially assessed the functional properties of the SC non-invasively in retinoid-treated humans and experimental animals. SC hydration and barrier function were assessed by measurement of high-frequency conductance and transepidermal water loss (TEWL), respectively. Daily application of topical retinoic acid creams was found to rapidly induce a time- and dose-dependent, linear increase in SC hydration of the forearm skin of healthy adults over a 2-week period and to compromise its water barrier function in a similar fashion. Systemic administration of high-dosage etretinate, 4 or 8 mg/kg/day, to guinea-pigs also induced dose-dependent increases in both SC hydration and TEWL measured on the plantar skin after 1 month. Moreover, in the animals given etretinate 4 mg/kg/day we confirmed a slight but significant decrease in the number of cell layers of the plantar SC. Likewise, patients with various dermatoses began to show similar functional changes of the SC in the uninvolved skin of the flexor surface of the forearms 3 weeks after the start of oral etretinate treatment, consisting of 50 mg daily for 2 weeks, followed by gradual dose tapering.(ABSTRACT TRUNCATED AT 250 WORDS)     

Functional properties of the stratum corneum in patients with diabetes mellitus: similarities to senile xerosis

BACKGROUND: Although diabetes mellitus is known to induce many pathophysiological changes in the skin, none of the earlier studies has focused on the state of the stratum corneum (SC) in patients with diabetes. In our previous report on a diabetic mouse model, we described a decreased SC hydration state and abnormalities in the function of the sebaceous gland together with a normally retained barrier function of the SC. OBJECTIVES: To examine the functional changes of the SC in patients with diabetes. METHODS: The following values were measured in 49 patients with diabetes: fasting plasma glucose (FPG) and haemoglobin A1c (HbA1c); skin surface lipid level on the forehead; and high-frequency conductance (HFC) and transepidermal water loss (TEWL) of the SC of the volar forearm and extensor surface of the lower leg. These functions of the SC were compared in two pairs of patient groups, i.e. between groups with high and low FPG, and between groups with high and low HbA1c. RESULTS: The HFC levels on the extensor leg and volar forearm were significantly lower in the group with high FPG (FPG > 110 mg dL(-1)) than in the group with low FPG (FPG < 110 mg dL(-1)), although TEWL values were almost the same in these two groups. The skin surface lipids on the forehead were significantly lower in the former than in the latter. The HFC did not differ significantly between the group with high HbA1c (HbA1c > 5.8%) and the group with low HbA1c (HbA1c < 5.8%), whereas the TEWL of the volar forearm was slightly lower in the former than in the latter. CONCLUSIONS: These new results as well as our earlier results with diabetic mice suggest that patients with diabetes mellitus tend to show a reduced hydration state of the SC together with decreased sebaceous gland activity, without any impairment of the SC barrier function.     

Assessment of effects of an additional dietary natural mineral water uptake on skin hydration in healthy subjects by dynamic barrier function measurements and clinic scoring

BACKGROUND/AIMS: The skin protects the body's organs and tissues from damage and physical, chemical and bacteriological injuries. It also prevents the transcutaneous loss of water. The present study was conducted to assess the effects of additional dietary natural mineral water uptake on skin hydration and cutaneous well-being in subjects with dry skin. METHODS: Eighty subjects (44 women and 36 males, mean age 56+/-5.6 years) were included in the study, randomised per forearm and stratified by gender. Skin surface hydration, transepidermal water loss (TEWL), sorption-desorption test, skin colour, thickness and micro-relief were evaluated on the forearms. Clinical scoring of dryness, roughness and elasticity was performed by a dermatologist. RESULTS: An improvement of skin hydration was observed after additional water uptake, statistically modifying the hydration level as well as TEWL, the water-binding capacity of the uppermost layers of the stratum corneum. Improvements of softness, smoothness and skin-moisturising effect were perceived by healthy subjects, and skin micro-relief was improved. CONCLUSION: We suggest that natural mineral water supplementation may be used in order to improve the hydration of skin dryness as a complementary cosmetic approach.