Barrier recovery and influence of irritant stimuli in skin treated with a moisturizing cream

Moisturizers are used daily by many people to alleviate symptoms of clinically and subjectively dry skin. Recent studies suggest that certain ingredients in creams may accelerate the recovery of a disrupted barrier and decrease the skin susceptibility to irritant stimuli. In the present single-blind study, a moisturizing cream was tested for its influence both on barrier recovery in surfuctant-damaged skin and on the susceptibility of normal skin to exposure to the irritant sodium lauryl sulphate (SLS). Parameters measured were transepidermal water loss (TEWL) and skin corneometer values, indicating degree of hydration. Treatment of surfactant-damaged skin with the test cream for 14 days promoted barrier recovery, as observed as a decrease in TEWL. Skin corneometer values also normalized more rapidly during the treatment. In normal skin, use or the test cream significantly reduced TFWL after 14 days of treatment, and irritant reactions to SLS were, significantly decreased. Skin corneometer values increased after only 1 application and remained elevated after 14 days. In conclusion, the accelerated rate of recovery of surfactant-damaged skin and the lower degree of SLS-induced irritation in normal skin treated with the test cream may be of clinical relevance in attempts to reduce contact dermatitis due to irritant stimuli.     

舒敏保湿特护霜射频导入治疗敏感性皮肤疗效评价

目的:评价射频导入舒敏保湿特护霜治疗面部敏感性皮肤的有效性和安全性.方法:将40例敏感性皮肤患者随机分为治疗组和对照组,每组20例.两组均口服枸地氯雷他定片8.8 mg/d,治疗组外用舒敏保湿特护霜,对照组外用凡士林霜,每日两次,联合射频导入治疗,1次/周,持续治疗4周.分别于0周、4周做疗效判定,使用CK无创皮肤检测...     

The effect of aqueous cream BP on the skin barrier in volunteers with a previous history of atopic dermatitis

Background The emollient aqueous cream BP is frequently used for the treatment of atopic dermatitis (AD), yet it is associated with a high rate of adverse cutaneous reactions. It contains the harsh anionic surfactant sodium lauryl sulphate, a known negative environmental factor associated with the exacerbation of AD. Objectives To investigate the effect of aqueous cream BP on stratum corneum (SC) integrity and skin barrier function in volunteers with a predisposition to a defective skin barrier. Methods Thirteen volunteers with a previous history of AD (no symptoms for 6 months) applied aqueous cream BP twice daily to the volar side of one forearm for 4 weeks. The other forearm was left untreated as a control. Permeability barrier function and SC integrity were determined before and after treatment by measuring transepidermal water loss (TEWL) in conjunction with tape‐stripping. For comparison, 13 volunteers with current AD were recruited for assessment, without treatment, of SC integrity and skin barrier function at unaffected sites. Results Topical application of aqueous cream BP resulted in significant elevation of baseline TEWL and a concomitant decrease in SC integrity. Measurements made after no treatment in volunteers with current AD, at unaffected sites, suggest that application of aqueous cream BP negatively affects the skin barrier towards the damaged state associated with onset of flares of the disease. Conclusions Aqueous cream BP used as a leave‐on emollient caused severe damage to the skin barrier in volunteers with a previous history of AD. Aqueous cream BP should not be used as a leave‐on emollient in patients with AD.     

Improvement in skin barrier function in patients with atopic dermatitis after treatment with a moisturizing cream (Canoderm)

Patients with atopic skin show a defective barrier function both in rough and in clinically normal skin, with an increasing risk of developing contact dermatitis. Moisturizing creams are often used in the treatment of dry skin. The purpose of this study was to investigate the influence of treatment with a urea-containing moisturizer on the barrier properties of atopic skin. Fifteen patients with atopic dermatitis treated one of their forearms twice daily for 20 days with a moisturizing cream. Skin capacitance and transepidermal water loss (TEWL) were measured at the start of the study and after 10 and 20 days. On day 21 the skin was exposed to sodium lauryl sulphate (SLS) and on day 22 the irritant reaction was measured non-invasively. Skin capacitance was significantly increased by the treatment, indicating increased skin hydration. The water barrier function, as reflected by TEWL values, tended to improve (P = 0.07), and the skin susceptibility to SLS was significantly reduced, as measured by TEWL and superficial skin blood flow (P < 0.05). Thus, it seems that certain moisturizers could improve skin barrier function in atopics and reduce skin susceptibility to irritants. The mechanism and the clinical relevance need further investigation.     

The 24‐hr, 28‐day,and 7‐day post‐moisturizing efficacy of ceramides 1, 3, 6‐II containing moisturizing cream compared with hydrophilic cream on skin dryness and barrier disruption in senile xerosis treatment

Direct replacement of decreased ceramides in the stratum corneum can be efficacious for skin hydration, skin barrier function, and skin pH. Our study aimed to evaluate the 24‐hr, 28‐day, and 7‐day post‐moisturizing efficacy of ceramide‐containing moisturizer in senile xerosis treatment. A split site, double‐blinded, randomized, controlled study was conducted in 24 senile subjects (91.7% females, mean age 54.83 ± 5.45 years) with mild to moderate xerosis, who were randomized to receive ceramide‐containing moisturizer or hydrophilic cream, daily applied on each side of the shin. A single application of ceramide‐containing moisturizer increased skin hydration, while improving transepidermal water loss (TEWL) and skin pH for up to 24 hr, with statistically significant difference. After 28 days of twice‐daily application, more significant improvement on skin hydration, barrier function, and skin pH was observed in those with ceramide‐containing moisturizer at all‐time points. At day 28, there was a statistically significant decrease of hemoglobin index, wrinkle, and texture on the ceramide treated side. The 7‐day post‐moisturizing efficacy on the ceramide treated side was superior for skin hydration, TEWL, skin pH, and wrinkle. Thus, the ceramide‐containing moisturizer can be a novel promising treatment for senile xerosis.     

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.     

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.     

Combination therapy improves the recovery of the skin barrier function: an experimental model using a contact allergy patch test combined with TEWL measurements.

BACKGROUND: Nickel (Ni) allergic contact dermatitis (ACD) alters the skin barrier. OBJECTIVE: Our aim was to compare the efficacy of combination therapies on ACD, using a topical corticosteroid and a corneotherapy agent (barrier cream), with that of a single therapy with corticosteroids. METHODS: On day 1, 3 Ni test patches were applied on each forearm of 14 Ni-patch-test-positive females. Four contained 5% Ni and 2 physiological saline. Either topical corticosteroid or barrier cream were matched with the combination of both products on 3 of the 4 Ni ACD. The fourth was not treated. Clinical scoring, transepidermal water loss (TEWL) and stratum corneum (SC) capacitance were measured before (day 1) and after (days 4-8) ACD. RESULTS: The combination therapy showed a significant decrease in TEWL values and an increase in SC capacitance. CONCLUSION: Combining a topical corticosteroid with corneotherapy agents prevents the delay in the healing process of skin barrier disruption due to ACD.     

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     

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.     

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)     

The self-recovery of facial skin barrier and erythema after nanochip treatment

Objective: To determine the degree of acute skin damage and the time required for the recovery of facial skin barrier function after the skin was treated with micro-needles and nanochips of various tip lengths. Methods: For this split face comparative study, a total of 16 subjects were enrolled and randomly divided into 2 groups. In the first group, one of the facial side of each subject was treated with 0.25-mm long nanotips for a total of 6 times while the other facial side was treated with 0.25-mm traditional micro-needles with a straight blade for a total of 6 times. In the second group, one of the facial side was treated with 0.5-mm nanotips for a total of 6 times while the other facial side was treated with 0.5-mm traditional micro-needles with a straight blade for a total of 6 times. Evaluations for trans-epidermal water loss (TEWL), skin hydration and erythema were carried out at baseline, 0, 4, 8, 24, 48 and 72 hours after the treatment. Results: There was no significant difference in TEWL, skin hydration and erythema between the two facial sides of the subjects in the Group one who were treated with 0.25 mm nanochips and traditional micro-needles. However, in the subjects of the Group two, the mean TEWL of the facial side treated with 0.5 mm nanochips was relatively lower than that of the 0.5 mm traditional micro-needles treated facial side at 0, 4, 8 and 24 hours after the treatment. Mean erythema of the facial side treated with 0.5-mm nanochips micro-needles was also relatively lower than that of the 0.5-mm traditional micro-needles treated facial side at 8 hours after the treatment. Rapid recovery of skin barrier function was observed within 4–8 hours after treatment with various lengths of nanochips while it took at least 48–72 hours for recovery of skin barrier function after treatment with various lengths of traditional micro-needles as measured by TEWL. Conclusion: The skin disruption caused by nanotips treatment recovers quicker than the traditional microneedle treatment at equal lengths.     

Dynamics of skin barrier repair following preconditioning by a biotechnology-driven extract from samphire (Crithmum maritimum) stem cells

Background With aging, the barrier repair kinetics following any weakening of the epidermal permeability barrier function is commonly slowed down. Objective To assess the recovery rate of the epidermal permeability barrier function following controlled stripping and applications of samphire and control formulations. Method In 12 healthy subjects older than 50 years, controlled stratum corneum (SC) strippings were used to increase the transepidermal water loss (TEWL) just above 15 g/m²/h. This procedure followed a 14‐day skin preconditioning by daily applications of formulations enriched or not with a samphire (Crithmum maritimum) biomass. An untreated skin site served as control. The epidermal permeability repair kinetics was assessed for 14 days by daily measurements of both TEWL and the colorimetric value a*. Results A rapid (96 h) recovery to lower TEWL values was obtained at each of the samphire‐preconditioned sites (0.1% serum, 0.05% cream, the serum–cream association, and 0.5% silicone oil). This process was significantly (P < 0.001) faster than that on both the placebo‐preconditioned (silicone oil) and the untreated sites. No adverse inflammatory and sensory reactions were recorded. At the sites preconditioned by samphire formulations, the SC moisture (capacitance) was higher at completion of the study compared to inclusion. Conclusions The present experimental pilot study brings some clues supporting a beneficial boosting effect of samphire cell biomass on the kinetics of epidermal permeability barrier repair.     

Moisturizers change the mRNA expression of enzymes synthesizing skin barrier lipids

In a previous study, 7-week treatment of normal human skin with two test moisturizers, Complex cream and Hydrocarbon cream, was shown to affect mRNA expression of certain genes involved in keratinocyte differentiation. Moreover, the treatment altered transepidermal water loss (TEWL) in opposite directions. In the present study, the mRNA expression of genes important for formation of barrier lipids, i.e., cholesterol, free fatty acids and ceramides, was examined. Treatment with Hydrocarbon cream, which increased TEWL, also elevated the gene expression of GBA, SPTLC2, SMPD1, ALOX12B, ALOXE3, and HMGCS1. In addition, the expression of PPARG was decreased. On the other hand, Complex cream, which decreased TEWL, induced only the expression of PPARG, although not confirmed at the protein level. Furthermore, in the untreated skin, a correlation between the mRNA expression of PPARG and ACACB, and TEWL was found, suggesting that these genes are important for the skin barrier homeostasis. The observed changes further demonstrate that long-term treatment with certain moisturizers may induce dysfunctional skin barrier, and as a consequence several signaling pathways are altered.     

Facilitating facial retinization through barrier improvement

The utility of topical tretinoin as a treatment for improving the appearance of photodamaged skin is limited by irritation that occurs during the early phases of facial retinization. The observed side effects are consistent with stratum corneum barrier compromise. This paired double-blinded study was conducted to determine if preconditioning the skin with a barrier-enhancing cosmetic facial moisturizer before beginning tretinoin therapy and continuing moisturizer application during therapy would mitigate these side effects. Women with facial photodamage were recruited and randomly assigned to apply one cosmetic moisturizer to one side of the face and the other cosmetic moisturizer to the other side of the face twice daily for 10 weeks. One moisturizer contained a mixture of vitamins (niacinamide, panthenol, and tocopheryl acetate) to enhance stratum corneum barrier function, and the other moisturizer contained similar moisturizing ingredients but no vitamins. Daily full-face treatment with tretinoin cream 0.025% commenced 2 weeks into the study. Subjects' facial skin condition was monitored via investigator assessments, instrumental measurements, and subject self-assessments. The results show that improving stratum corneum barrier function before beginning topical tretinoin therapy and continuing use of a barrier-enhancing cosmetic moisturizer during therapy facilitates the early phase of facial retinization and augments the treatment response.     

Cosmetic formulations containing <Emphasis Type="Italic">Lithospermum erythrorhizon</Emphasis> root extract show moisturizing effects on human skin

Retention of water in the stratum corneum of skin epidermis plays an important role in regulation of skin function. Loss of water may decline skin appearance gradually and lead to irregular skin disorders. The root extract of Lithospermum erythrorhizon (LES) is known for its various pharmacological activities. However, the potential skin care effect of LES is not clear. The aim of this study was to evaluate the moisturizing efficacy and skin barrier repairing activity of LES. For this study, 30 healthy Asian females (age 20-30) with healthy skin had applied the test emulsions twice daily over a period of 28 days. The skin properties were measured by skin bioengineering techniques. Our preliminary results indicated that LES show moisturizing effect on skin hydration in a time- and dose-dependent pattern, and the maximum increase in skin humidity was 11.77 +/- 1.18% for emulsion LES5.00. Particularly, LES-containing emulsions significantly improve skin barrier function by decreasing the value of transepidermal water loss (TEWL) in a time- and dose-dependent pattern, and the maximum decrease in TEWL value was 7.68 +/- 0.79% for emulsion LES5.00. Taken together, our data demonstrate that LES is more effective in increasing skin humidity and decreasing the TEWL values, indicating the potential skin care effects of LES.     

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.     

Effect of a topical corticosteroid, a retinoid and a vitamin D3 derivative on sodium dodecyl sulphate induced skin irritation

Exposure of the skin to sodium dodecyl sulfate (SDS) leads to disruption of barrier and skin irritation. We used repetitive short exposure to a low molarity SDS solution as an in vivo model to mimic the development of irritant contact dermatitis. In this model, we studied clinical (erythema), functional (transepidermal water loss(TEWL)) and cell biological changes, 24 healthy volunteers were patch tested with SDS (0.2%) for 4 h a the day for 5 consecutive days. After removal of the patches, the exposed sites were treated 1 × daily either with a topical corticosteroid (triamcinolon acetoide cream 0.05%). a retinoid (tretinoin cream 0.025%). or a vitamin D₃ derivative (calcipotriol ointment 50 microgram/g). Irritant reactions were assessed by erythema scoring and measurement of barrier function with TEWL up to 14 days after the first challenge. Skin biopsies were taken for cell biological changes at day 4. Vehicle-treated sites served as controls. Repetitive exposure of human skin to SDS resulted in a gradual increase in erythema scoring and TEWL associated with the upregulation of proliferative cells as measured by the expression of Ki-67-antigen and of differentiation markers, visualized by increased expression of involucrin and epidermal-fatty-acid binding protein (E-FABP). Skin irritation as assessed by erythema scoring and TEWL was not significantly suppressed by triamcinolone cream. However, a significant reduction of the number of cycling keratinocytes and a decrease in involucrin positive cell layers was observed in this group. Neither treatment with calcipotriol ointment nor with tretinoin cream induced improvement of skin irritation as judged by visual scoring and TEWL. In contrast to steroid treatment no significant elf eel of calcipotriol ointment or tretinoin cream treatment was observed with regard to the number of cycling cells and differentiation markers. Further studies are needed to assess whether treatment with topical corticosteroids is an effective modality in skin irritation and irritant contact dermatitis.     

类人胶原蛋白敷料治疗面部脂溢性皮炎疗效观察及对皮肤屏障功能的影响

目的探讨类人胶原蛋白敷料治疗面部脂溢性皮炎的疗效、安全性及其对皮肤屏障功能的影响。方法将20~50岁女性面部脂溢性皮炎患者67例随机入组,试验组患者外用酮康唑乳膏加类人胶原蛋白敷料,对照组患者单独外用酮康唑乳膏,两组患者均用药10 d,观察皮损变化并测定皮肤屏障功能相关指标。结果第2次随访时,试验组症状积分[(1.06±1.06)分]、经皮水分丢失量(transepidermal water loss,TEWL)[(11.99±5.84)g/(m2?h)]均低于对照组[(1.94±1.17)分、(16.17±8.47)g/(m2?h)],角质层含水量(40.20±11.69)高于对照组(34.13±10.86),差异均有统计学意义(P=0.002,0.024,0.033)。两组患者均未出现明显不良反应。结论类人胶原蛋白敷料治疗成年女性面部脂溢性皮炎,能改善皮肤屏障功能,减轻皮损,可以作为面部脂溢性皮炎的一个安全有效的辅助治疗手段。     

Variation in barrier impairment and inflammation of human skin as determined by sodium lauryl sulphate penetration rate

BACKGROUND: Skin irritability after a brief exposure to the model skin irritant, sodium lauryl sulphate (SLS), is known to vary considerably between individuals. A difference in the skin barrier to SLS may contribute to this variation. To date, no human in vivo data have been available on SLS penetration into the skin. OBJECTIVES: We studied whether the SLS penetration rate into the stratum corneum (SC) is related to impairment of the water barrier function and inflammation of the skin. METHODS: The penetration of SLS into the SC was assessed using a noninvasive tape-stripping procedure in 20 volunteers after a 4-h exposure to 1% SLS. Additionally, the effect of a 24-h exposure to 1% SLS on the skin water barrier function was assessed by measuring the transepidermal water loss (TEWL). The accompanying inflammation was quantified by measuring erythema. RESULTS: The mean +/- SD diffusivity of SLS (D) and the SLS permeability coefficient (Kp) were 1.4 +/- 0.6 x 10(-8) cm2 h(-1) and 1.5 +/- 0.7 x 10(-3) cm h(-1), respectively. A multiple regression analysis showed that the baseline TEWL, SC thickness and SLS penetration parameters K (SC/water partition coefficient) and D clearly influenced the increase in TEWL after the 24-h irritation test (explained variance: r2 = 0.80). Change in erythema was mainly influenced by SC thickness. CONCLUSIONS: We found that variation in the barrier impairment and inflammation of human skin depends on the SLS penetration rate, which was mainly determined by SC thickness.