Analysis of the number of enlarged pores according to site, age, and sex.

BACKGROUND: Increasing the number of enlarged pores causes cosmetic problems. The difference in the number of enlarged pores according to facial site, age, and sex is unclear. OBJECTIVE: To analyze the distribution of the number of enlarged pores according to facial site, age, and sex. METHODS AND MATERIALS: We analyzed the number of the enlarged pores and the percentage of wrinkles in the nose, forehead, and cheek from 434 polarized images. The measurement results were analyzed according to site, age, and sex. Relationship between enlarged pore counts and wrinkle severity was also analyzed. The study was conducted by using DermaVision,™ which can take cross-polarization, parallel polarization, and ultraviolet light images. RESULTS: The enlarged pores of the nose and forehead were more prominent than in the cheeks. Pore counts were increased with age, and the increment was significant between the 30's and 40's. There was no significant difference by gender. Enlarged pore counts were related to wrinkle severity. CONCLUSIONS: The number of enlarged pores differs depending on body site and increased with age. The enlarged pore counts correlate with wrinkle severity and the correlation varies depending on the body site.

The relationship between clinical characteristics including presence of exposed lesions and health-related quality of life (HRQoL) in patients with psoriasis: analysis from the nationwide epidemiologic study for psoriasis in Korea (EPI-PSODE study).

BACKGROUND: Psychological aspect and quality of life should be considered in treating patients with psoriasis. OBJECTIVE: We sought to ascertain which clinical characteristics including presence of exposed lesions are associated with impairment of health-related quality of life (HRQoL) in patients with psoriasis. METHODS: The EPI-PSODE study was a nationwide, multicenter, cross-sectional study conducted in Korea that included 1260 adult patients with psoriasis. In addition to clinical characteristics including presence of exposed lesions, data were collected using the Psoriatic Arthritis (PsA) Screening and Evaluation (PASE), Dermatology Life Quality Index (DLQI), MOS 36-Item Short-Form Health Survey (SF-36), Work Productivity and Activity Impairment Questionnaire Psoriasis (WPAI: PSO) and Medication Satisfaction Questionnaire (MSQ). RESULTS: Patients with a DLQI score > 5 (n = 990) were younger, had an earlier onset of psoriasis, scored higher on the Psoriasis Area and Severity Index (PASI), had higher body surface area (BSA) and had higher PASE scores than patients with DLQI ≤ 5 (n = 266). The group of patients with exposed lesions (n = 871) were younger and male predominance, earlier onset of psoriasis, longer disease duration, higher PASI/BSA score and a higher proportion with drinking and smoking history each than the group of patients without exposed lesions (n = 389). Presence of exposed lesions negatively influenced DLQI, 36-Item Short-Form Health Survey (SF-36) (mental component), presenteeism, total work productivity impairment and total activity impairment in the WPAI: PSO. In multiple regression model, PASI score was the only variable which was significantly associated with all HRQoL measures. Presence of exposed lesions was a significant factor affecting DLQI and SF-36 (mental). CONCLUSION: The presence of exposed lesions has a negative impact on quality of life, mental health and work productivity. Therefore, effective treatments are particularly needed for psoriasis patients with exposed lesions.

Optimal maintenance treatment with calcipotriol/betamethasone dipropionate gel in Korean patients with psoriasis vulgaris: a multicentre randomized, controlled clinical trial.

BACKGROUND: There is a lack of response data for topical treatments for psoriasis vulgaris in Asian patients. OBJECTIVES: To determine the optimal maintenance regimen for topical treatment with calcipotriol monohydrate/betamethasone dipropionate gel in Korean patients with psoriasis vulgaris, by comparing the efficacy of three 8-week maintenance regimens. METHODS: This was a multicentre, prospective, randomized, controlled, parallel-group, open-label, phase 4 clinical trial, conducted in South Korea. Patients with psoriasis vulgaris on the limbs/trunk received once-daily treatment with calcipotriol monohydrate (50 µg/g)/betamethasone dipropionate (500 µg/g) gel for 8 weeks (induction phase). Responders (defined as an Investigator's Global Assessment of Disease Severity (IGA) grade of 'clear' or 'almost clear') were then randomized to receive 8 weeks' maintenance treatment with Xamiol® gel once daily as needed [pro re nata (PRN Group)], once daily every day (Continuous group), or twice weekly - on Saturday and Sunday (Weekend group). The primary endpoint was the percentage of IGA responders at week 16. RESULTS: At the end of the induction phase, 62.18% of patients were IGA responders. At the end of the maintenance phase (week 16), the responder rate was 63.89% for the PRN group, 67.5% for the Continuous group and 31.43% for the Weekend group. The PRN and Continuous groups were statistically superior to the Weekend group (P = 0.0109 and P = 0.0015), but the PRN and Continuous groups did not differ statistically. The incidence of adverse events did not differ significantly between the groups. CONCLUSION: Among Korean patients with psoriasis vulgaris, maintenance treatment with calcipotriol monohydrate/betamethasone dipropionate using a continuous daily regimen or an 'as needed' daily regimen provided similar efficacy, whereas a twice-weekly regimen was significantly less efficacious than either of these regimens.

Psoriasis concurrent with inflammatory bowel disease.

BACKGROUND: Previous studies have indicated an association between psoriasis and inflammatory bowel disease (IBD), and the concurrence of the two diseases reportedly has higher morbidities in Caucasian populations. However, reports on the concurrence of psoriasis with IBD in the Asian population in the literature are scarce. Objective To analyse the characteristics of psoriasis concurrent with IBD and investigate the associated morbidity in the Asian population. METHODS: We retrospectively examined the medical records of 15 patients with a confirmed diagnosis of both psoriasis and IBD. Sixty age-, gender-, and ethnicity-matched patients with a confirmed diagnosis of only psoriasis were included as controls. Both cases and controls had visited the Seoul National University Hospital or Seoul National University Boramae Hospital between 1990 and 2012. The characteristics of psoriasis, presence of comorbidity and laboratory parameters were compared between the two groups. RESULTS: Compared to controls with psoriasis only, cases of psoriasis concurrent with IBD had a younger age of onset, longer duration of psoriasis and a higher Psoriasis Area Severity Index (PASI) score. A larger proportion of cases was treated with phototherapy, systemic therapy and biologics. However, all these differences above were not statistically significant. Cases of psoriasis with concurrent IBD showed higher erythrocyte sedimentation rate and C-reactive protein levels compared with the controls (both P = 0.000). Furthermore, this case group had a higher proportion of patients with psoriatic arthritis and with more than one autoimmune disease as compared with the control group (P = 0.007 and 0.005 respectively). CONCLUSION: Asian patients having psoriasis concurrent with IBD exhibited different characteristics as compared with those having psoriasis only, particularly in terms of psoriasis severity, risk of psoriatic arthritis, systemic inflammatory parameters and presence of autoimmune comorbidity. However, further studies elucidating the exact pathogenesis and including a larger number of patients are required.

Could colorimetric method replace the individual minimal erythemal dose (MED) measurements in determining the initial dose of narrow-band UVB treatment for psoriasis patients with skin phototype III-V?

BACKGROUND: Assessment of minimal erythemal dose (MED) for individual patients has been used to guide the narrowband Ultraviolet B (NB-UVB) phototherapy, which sometimes causes discomfort and additional time. The L* value (the lightness of color in Commission Internationlale de l'Eclairge L*a*b* color scale) measured by colorimeter was shown to be useful for predicting sensitivity to NB-UVB irradiation. OBJECTIVE: To compare the efficacy and safety of NB-UVB phototherapy between 50% of MED and colorimetric L* value starting dose regimens for skin phototype III-V Korean patients with psoriasis. METHOD: Twenty seven patients determined starting doses based on colorimetric L* value, and 27 patients based on 50% of MED. Since correlation analysis showed that L* value had the most significant association with MED compared with skin phototypes, a*, and b* values, we designated starting doses of L* value regimen as follows: 300 mJ/cm(2) (L* >66), 400 mJ/cm(2) (62 < L* ≤ 66), and 500 mJ/cm(2) (L* ≤ 62). RESULTS: There was no significant difference between two groups in clinical efficacy including response rate, mean number of sessions, duration of treatment, maximum dose and cumulative dose until achieving the state of near clearance. The proportion of adverse effects was not also significantly different. CONCLUSIONS: NB-UVB starting dose determination based on colorimetric L* value was comparable with conventional MED based regimen in efficacy and safety for skin phototype III-V patients. Since it provides much convenience and ease for both patients and physicians, colorimetric L* value could partly substitute the MED checking methods in NB-UVB phototherapy.

A comparison of serum inflammatory cytokines according to phenotype in patients with psoriasis.

BACKGROUND: Plaque-type psoriasis manifests with various morphological phenotypes and different clinical activity over time in the same individual or from one patient to another. Circulating cytokines, especially T-helper (Th) 1- and Th17-related, have been suggested to reflect the inflammatory nature of psoriasis. However, studies regarding cytokine profile according to morphological phenotypes are quite scarce. OBJECTIVES: We sought to analyse the circulating Th1 and Th17 cytokines according to clinical phenotype and investigated the correlation between disease severity [Psoriasis Area and Severity Index (PASI)] and the serum level of inflammatory cytokines. METHODS: Seventy-one patients with psoriasis were divided into two groups according to clinical phenotype: chronic stable (CS) and eruptive inflammatory (EI). Th1- and Th17-derived cytokines were measured using multiplex cytokine assay. RESULTS: It was noted that interleukin (IL)-1 receptor antagonist and IL-17A were elevated in the EI group compared with the CS group. We also noticed that the PASI is relatively well correlated with serum cytokine level in the CS state but not as well in the EI counterpart. CONCLUSIONS: The level of serum inflammatory cytokines differs according to morphological phenotype. Also, the PASI does not seem to be a suitable tool to assess disease severity in patients with psoriasis with EI characteristics.

Cross-sectional study on the correlation of serum uric acid with disease severity in Korean patients with psoriasis.

BACKGROUND: Hyperuricaemia is a common finding in patients with psoriasis. However, previous studies have reported inconsistent results about the association between serum uric acid concentration (SUAC) and psoriasis severity. Recent studies have also reported that SUAC is associated with metabolic dysregulation. AIM: To assess any association between SUAC and clinical features of psoriasis, and to investigate the characteristics of patients with psoriasis with hyperuricaemia compared with similar patients with normouricaemia. METHODS: Cross-sectional data from 198 Korean patients with psoriasis who visited our clinic were analysed. Association of SUAC with clinical features of psoriasis, body mass index (BMI) and various laboratory values was assessed in both genders separately. RESULTS: The average uric acid concentration of patients with psoriasis was not significantly different from that of the healthy population, for both genders (P > 0.05). There was a positive correlation between SUAC and Psoriasis Area and Severity Index (PASI) and BMI in patients with psoriasis (P < 0.05). There was no association with age of disease onset, family history of psoriasis, or other laboratory values (P > 0.05), in either gender. Of the other factors of disease severity, the extent of body surface involvement was correlated with uric acid concentration (P < 0.05) although there was no significant relationship with activity of individual lesions (P > 0.05). Mean PASI and extent of psoriasis were increased in hyperuricaemic compared with normouricaemic patients (P < 0.05). CONCLUSIONS: SUAC in patients with psoriasis is positively associated with PASI, extent of skin involvement and BMI for both genders independently.

Branched oligomerization of cell-permeable peptides markedly enhances the transduction efficiency of adenovirus into mesenchymal stem cells.

Cell-permeable peptides (CPPs) promote the transduction of nonpermissive cells by recombinant adenovirus (rAd) to improve the therapeutic efficacy of rAd. In this study, branched oligomerization of CPPs significantly enhanced the transduction of human mesenchymal stem cells (MSCs) by rAd in a CPP type-independent manner. In particular, tetrameric CPPs increased transduction efficiency at 3000-5000-fold lower concentrations than did monomeric CPPs. Although branched oligomerization of CPPs also increases cytotoxicity, optimal concentrations of tetrameric CPPs required for maximum transduction are at least 300-1000-fold lower than those causing 50% cytotoxicity. Furthermore, although only approximately 60% of MSCs were maximally transduced at 500 muM of monomeric CPPs, >95% of MSCs were transduced with 0.1 muM of tetrameric CPPs. Tetrameric CPPs also significantly increased the formation and net surface charge of CPP/rAd complexes, as well as the binding of rAd to cell membranes at a greater degree than did monomeric CPPs, followed by rapid internalization into MSCs. In a critical-size calvarial defect model, the inclusion of tetrameric CPPs in ex vivo transduction of rAd expressing bone morphogenetic protein 2 into MSCs promoted highly mineralized bone formation. In addition, MSCs that were transduced with rAd expressing brain-derived neurotrophic factor in the presence of tetrameric CPPs improved functional recovery in a spinal cord injury model. These results demonstrated the potential for tetrameric CPPs to provide an innovative tool for MSC-based gene therapy and for in vitro gene delivery to MSCs.

High-concentration (20 µg g⁻¹ ) tacalcitol ointment in the treatment of facial psoriasis: an 8-week open-label clinical trial.

BACKGROUND: Facial psoriasis gives rise to considerable concern because of associated cosmetic problems and psychosocial distress. It requires a treatment approach other than topical corticosteroids, which bear a risk of cutaneous adverse reactions. Recently, topical tacalcitol has been shown to be effective in psoriasis. OBJECTIVES: The aim of this open-label single-centre study is to investigate the efficacy and safety of high-concentration (20 µg g⁻¹) ) tacalcitol ointment (Bonalfa-high(®) , Teijin Pharma, Tokyo, Japan) in patients with facial psoriasis and to evaluate clinical response according to the distribution of facial psoriatic lesions. PATIENTS AND METHODS: Thirty-seven patients were enrolled to this clinical trial. Tacalcitol 20 µg g⁻¹ ointment was applied once daily to psoriatic lesions of the face over an 8-week period. Patients were also categorized into three subtypes according to facial lesion distribution. Efficacy was evaluated by the facial Psoriasis Area and Severity Index (facial PASI) and the Physician's Global Assessment (PGA) score at weeks 2, 4 and 8. The Subjective Global Assessment (SGA) was also determined at the end of the study. RESULTS: Thirty-three patients completed the clinical trial. Mean facial PASI of 33 patients at baseline was 9·58 and after 8 weeks of treatment the mean facial PASI decreased significantly to 3·88. By using PGA, patients showed the following responses to treatment: clearance (n = 1); excellent (6); good (16); fair (4); slight (5); no change (1). The response rate among the three facial psoriasis types showed no difference. Using the SGA, 27 (82%) of the patients presented excellent (15%) or good (67%) effect with tacalcitol 20 µg g⁻¹ ointment. No serious adverse reactions were observed. CONCLUSIONS: This is the first clinical study reporting a relevant therapeutic effect and favourable safety profile of tacalcitol 20 µg g⁻¹ ointment in facial psoriasis. These results suggest that tacalcitol 20 µg g⁻¹ ointment can be used as the first-line treatment in patients with facial psoriasis.

A fully validated HPLC method for the simultaneous determination of acitretin and etretinate in plasma and its application to a pharmacokinetic study in healthy Korean subjects.

OBJECTIVE: Acitretin is used for the treatment of psoriasis. The purpose of this study was to validate an HPLC method for the determination of acitretin and etretinate and to investigate the pharmacokinetic characteristics of acitretin in healthy Korean subjects. MATERIALS AND METHODS: Plasma samples or calibrators were mixed with acetonitrile and retinyl acetate (internal standard). Butanol: acetonitrile (1:1 v/v) and K2HPO4 were added later. After vortexing, 30 microl of the supernatant was injected directly into the analytical column of an HPLC system. The samples were separated by C18 reversed phase HPLC and UV detection was performed at 350 nm. Various assay performances were evaluated. RESULTS: The linearity of acitretin and etretinate was adequate up to 500 ng/ml (R2 = 0.9937 for acitretin and R2 = 0.9923 for etretinate). The accuracy was 89.5 - 113.5% and the precision was satisfactory (within-run CV, 4.4 - 15.8%; between-run CV, 3.3 - 17.4%). The LLOQ was 2 ng/ml and the stability and specificity were satisfactory. However, after storage at room temperature for 24 h under light exposure, the concentrations of acitretin and etretinate decreased by 26.0 - 66.5%. Extraction recovery was 75.1 - 91.5%. Nine healthy Korean subjects were evaluated to study the pharmacokinetics of acitretin. A single oral dose of 30 mg acitretin (Neotigason, Roche Pharmaceuticals) was given to all volunteers. The mean +/- SD pharmacokinetics of acitretin in Koreans were as follows: Cmax 148.7 +/- 93.0 ng/ml, tmax 3.2 +/- 1.3 h, t1/2 81.2 +/- 26.5 h, and AUClast 2641.9 +/- 1274.8 ng h/ml. CONCLUSION: A simple HPLC method for the simultaneous determination of acitretin and etretinate was validated, and the pharmacokinetic characteristics of acitretin in the Korean population were investigated.

Effects of 12-O-tetradecanoyl-phorbol-13-acetate [corrected] and sodium lauryl sulfate on the production and expression of cytokines and proto-oncogenes in photoaged and intrinsically aged human keratinocytes.

Skin aging may be divided into photoaging and intrinsic aging. The purpose of this study was to investigate the effects of 12-O-tetradecanoyl-phorbol-13-acetate and sodium lauryl sulfate on the production and expression of cytokines and proto-oncogenes in photoaged and intrinsically aged skin, compared with young skin. Keratinocytes were taken from newborns, young adults in their twenties, and from the forearm and thigh of volunteers in their fifties and seventies. Interleukin-1alpha and -6, and interleukin-1 receptor antagonist, c-fos and c-myc were measured after cultured keratinocytes had been treated with 12-O-tetradecanoyl-phorbol-13-acetate and sodium lauryl sulfate. There has been no report concerning the dependence of cytokine production by sodium lauryl sulfate upon photoaging and intrinsic aging. This study also involves the first investigation of the effects of aging on c-myc expression by 12-O-tetradecanoyl-phorbol-13-acetate treatment. Cytokine production decreased markedly with age. These results suggest the progressive decline of cellular function with age. The ratio of cytokine production in the irritant-treated group compared with that in the control group showed a different pattern in photoaging and intrinsic aging. With the significant difference between photoaging and intrinsic aging, T/C ratio decreased in interleukin-1alpha and interleukin-1 receptor antagonist upon aging, whereas it increased in interleukin-6. S/C ratio was uniquely elevated on photoaged skin in the 50 y age group. It is suggested that photoaged skin shows an exaggerated reaction to surfactant. Compared with the control, c-fos expression in 12-O-tetradecanoyl-phorbol-13-acetate-treated keratinocytes decreased with age in the thigh, but increased in the photoaged skin of forearm. The increased c-fos expression in 12-O-tetradecanoyl-phorbol-13-acetate-treated keratinocytes could be relevant for the predisposition of photoaged keratinocytes to malignant transformation.

The association of psoriasis with human leukocyte antigens in Korean population and the influence of age of onset and sex.

To identify HLA markers that may contribute to the genetic susceptibility of Koreans to psoriasis, we studied 84 psoriasis patients, with serologic HLA types of A, B, and genotypes of HLA-Cw, DRB1, DQA1, DQB1, DPB1 alleles. The distribution of HLA markers and the associated haplotypes were analyzed according to age and sex. HLA-Cw*0602 showed the strongest association with psoriasis (relative risk = 36.0, p < 10-8, Pc < 8 x 10-7). The frequencies of A1 (relative risk = 17.0, p < 9 x 10-7, Pc < 7 x 10-5), A30 (relative risk = 5.5, p < 2 x 10-5, Pc < 0.001), B13 (relative risk = 5.6, p < 4 x 10-6, Pc < 3 x 10-4), B37 (relative risk = 30.3, p < 7 x 10-7, Pc < 6 x 10-5), DRB1*07 (relative risk = 5.9, p < 2 x 10-6, Pc < 8 x 10-5), DRB1*10 (relative risk = 26.4, p < 4 x 10-6, Pc < 3 x 10-4), DQA1*02 (relative risk = 6.2, p < 5 x 10-7, Pc < 4 x 10-4), DQB1*02 (relative risk = 2.5, p < 0.005, Pc = ns) and DPB1*1701 (relative risk = 24.6, p < 9 x 10-6, Pc < 7 x 10-4) were also significantly increased in Korean psoriasis patients. Type I and type II psoriasis were subdivided into groups of below and above 30 y of age, because of the significant difference found in HLA-Cw*0602 phenotype frequency between the two groups (83.9% vs. 54.5%, p < 0. 009). In addition to HLA-Cw*0602, the frequencies of B37 and DPB1*1701 were significantly higher in type I as opposed to type II psoriasis. HLA-A30-B13-Cw*0602-DRB1*07-DQA1* 02-DQB1*02 was identified as a high risk haplotype. This was particularly true at an early age in the female. HLA-A33-B44-Cw*1401-DRB1*13-DQA1* 01-DQB1*06-DPB1*0401 was defined as a protective haplotype for psoriasis. The extended haplotype HLA-A1-B37-Cw*0602-DRB1*10-DQA1*01-DQB1*05 was discovered to be a high-risk factor in Koreans. To summarize, this study demonstrates the differential association of HLA according to sex, and identifies a newly found high-risk haplotype and a protective haplotype in Korean psoriasis patients.

Vitamin D receptor polymorphism is associated with psoriasis.

Vitamin D receptor is a trans-acting transcriptional factor that mediates 1alpha,25-dihydroxyvitamin D3 action in the regulation of target gene expression. Recent studies have shown that clinical response of psoriasis to 1alpha,25-dihydroxyvitamin D3 is correlated with the vitamin D receptor mRNA expression level, which may be influenced by the genotype of the vitamin D receptor. In this study, we have explored a possible association between psoriasis and the polymorphism in the gene encoding the vitamin D receptor. We examined the allelic frequencies of the vitamin D receptor in psoriasis patients (n = 104) and in healthy controls (n = 104) by analyzing the restriction pattern of the polymerase chain reaction products. A significant increase in the frequency of the A allele (absence of the restriction site at intron 8) by ApaI restriction fragment length polymorphism was observed in psoriasis patients compared with that of the control group, and the tendency was more accentuated in early onset psoriasis. Odds ratios (95% confidence interval) for psoriasis of AA and Aa genotypes were 5.0 (1.3-19.1) and 2.4 (1.3-4.3), and odds ratios for early onset of AA and Aa genotypes were 6.4 (1.6-25.0) and 3.1 (1.7-5.9), respectively. Allele frequencies for A and a alleles were 0.317 and 0.683 in the psoriasis group and 0.168 and 0.832 in the control group (p = 0.001). A significant association between vitamin D receptor genotypes and the mean age at onset was observed (p < 0.05). Our findings suggest that allelic variance in the vitamin D receptor gene itself or other genes in linkage disequilibrium with this gene, could predispose to the development of psoriasis.

Ultraviolet B irradiation-enhanced interleukin (IL)-6 production and mRNA expression are mediated by IL-1 alpha in cultured human keratinocytes.

Ultraviolet (UV) B radiation may trigger cutaneous inflammatory responses by directly inducing epidermal keratinocytes to elaborate specific cytokines such as interleukin (IL-1) and IL-6. Because IL-1 is a potent inducer of IL-6, one may speculate that the release of IL-6 by keratinocytes after UV exposure is mediated via the release of IL-1 in an autocrine or paracrine manner. We demonstrated that UVB irradiation upregulated IL-1 alpha mRNA at a lower dose (15 mJ/cm2) and then downregulated IL-1 alpha mRNA expression at high doses (30-40 mJ/cm2). The kinetic profile of IL-1alpha mRNA expression showed a biphasic response, with the early increase by 1 h after UV exposure and the secondary increase at 6 h after UV. On the other hand, the expression of IL-6 mRNA was increased with increasing doses of UVB (0-45 m/J/cm2) and showed a single peak at 6 h post UV. These results may indicate that UVB radiation could regulate the expression of IL-1alpha and IL-6 mRNA in keratinocytes by different mechanisms. Our data show that anti-human IL-1alpha antibody inhibits UV-induced IL-6 production and mRNA expression in cultured keratinocytes. The addition of recombinant IL-1alpha to the medium increased IL-6 synthesis and augmented IL-6 production and mRNA expression in cultured human keratinocytes by UVB irradiation. These results support the hypothesis that UVB irradiation-enhanced IL-6 production and mRNA expression may be mediated by IL-1alpha.

Effect of ultraviolet A on IL-1 production by ultraviolet B in cultured human keratinocytes.

Human skin is exposed to significant amounts of UVA and UVB radiation simultaneously. The effects of UVA and UVB interactions have been examined in many aspects such as erythema response. The effects of UVA on the production of cytokines by UVB have not been studied yet. The purpose of this study is to observe the effect of UVB and UVA on the production of IL-1 in cultured human keratinocytes and to determine whether UVA can modify the effects of UVB on the IL-1 production. Human keratinocytes derived from normal foreskin were exposed to UVA (0-30 J/cm2) and subsequently to UVB (0-50 mJ/cm2). After 48 h incubation, IL-1 levels in the culture supernatants and cell extracts of the cultured keratinocytes were measured by thymocyte proliferation assay. We have observed that UVB increased the production of IL-1 in cultured keratinocytes. However, UVA suppressed the production of IL-1 and also the stimulatory effect of UVB on the IL-1 production. We think that the opposite effects of UVB and UVA on the IL-1 production in human keratinocytes might explain the different action mechanisms of UVB and UVA in many cutaneous responses.

The photoprotective effect of 1,25-dihydroxyvitamin D3 on ultraviolet light B-induced damage in keratinocyte and its mechanism of action.

We investigated the photoprotective effect of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) both in vivo and in vitro, revealing its relationship with glutathione, a well-known antioxidant. We also probed into the possible mechanism of photoprotection of 1,25(OH)2D3 through immunohistochemical study for metallothionein (MT). At the same time, endogenous antioxidant effect of 1,25(OH)2D3 was examined. Survival of cultured human keratinocytes was decreased when the cells were irradiated with ultraviolet light-B (UVB) at doses above 30 mJ/cm2. But in the presence of 1,25(OH)2D3 (12 nM), the decrease of survival of keratinocytes by UVB was diminished. The formation of sunburn cells by UVB irradiation in the skin of ICR mice was inhibited by topical application of 1,25(OH)2D3, regardless of prior glutathione depletion. Immunohistochemical staining revealed that 1,25(OH)2D3 induced the expression of MT, a potent radical scavenger, mainly in the basal layer of ICR mice skin. 1,25(OH)2D3 neither inhibited peroxidation of plasma lipids nor interacted with superoxide, nor removed hydrogen peroxide as an antioxidant. These findings suggest that 1,25(OH)2D3 has photoprotective effect not related with glutathione or its endogenous antioxidant property. Rather, it could be attributed to 1,25(OH)2D3-induced MT and its capacity to prevent radical-related damage in UVB irradiation.

Change of glutathione S-transferases in the skin by ultraviolet B irradiation.

Glutathione S-transferases (GSTs) may play an important role in protecting skin from ultraviolet radiation (UVR). However, the study on the response of GST to UVR is limited at present. We have examined the effects of a single exposure to ultraviolet B (UVB) radiation on GST in cultured human keratinocytes and the epidermis of SKH/hr-1 hairless mice. We have also investigated the changes of skin GST by chronic irradiation of UVB on the hairless mice. Significant decreases in GST activities in vitro and in vivo were observed at 24 h after 30 and 50 mJ/cm2 UVB irradiation. Chronic UVB exposure also caused decrease in GST activities of the skin tissue. However, any changes in mRNA expression or protein amount of GST have not been observed by Northern blot analysis and Western blot analysis after 30 mJ/cm2 UVB irradiation in cultured human keratinocytes, which suggests that mRNA expression and protein amount of GST are not affected by UVB. These results suggest that UVB irradiation results in inhibitory effect on GST activity in the skin.

Regulations of collagen synthesis by ascorbic acid, transforming growth factor-beta and interferon-gamma in human dermal fibroblasts cultured in three-dimensional collagen gel are photoaging- and aging-independent.

Decreased collagen synthesis and loss of responsiveness to growth factors are well known phenomena in in vivo or in vitro aged cells. Ascorbic acid and some cytokines such as transforming growth factor-beta and interferon-gamma are important regulators of collagen synthesis. To investigate the responsiveness of fibroblasts with regard to the photoaging and aging process, we examined the effect of ascorbic acid, TGF-beta, and IFN-gamma on collagen synthesis in dermal fibroblasts from three newborn foreskins (1 day old) and in both exposed and unexposed skin fibroblasts from 4 old individuals (60-76 years old) cultured in monolayer and in collagen gel. We demonstrated that basal levels of collagen synthesis decreased with increasing age. Photoaged fibroblasts in collagen gel showed greater basal collagen synthesis than aged fibroblasts in the same individuals, but similar basal collagen synthesis in monolayer cultures. Even though basal levels of collagen synthesis in collagen gel are downregulated in a photoaging- and aging-dependent manner, collagen synthesis by ascorbic acid in collagen gel, and by TGF-beta and IFN-gamma in both monolayer culture and collagen gel were regulated in a photoaging- and aging-independent manner. In monolayer culture, however, the responsiveness to ascorbic acid in newborn fibroblasts was greater than in photoaged and aged fibroblasts. Our results suggest that there are differences in collagen synthesis between photoaged and aged cells, depending on culture conditions. Responsiveness to ascorbic acid, TGF-beta and IFN-gamma related to collagen synthesis in photoaged and aged fibroblasts in collagen gel appears to be the same as in newborn fibroblasts, even though basal levels of collagen synthesis are downregulated in a photoaging- or aging-dependent manner.

Reconstruction of human hard-palate mucosal epithelium on de-epidermized dermis.

Artificial hard-palate mucosa equivalents were reconstructed using keratinocytes derived from normal human hard-palate and de-epidermized dermis. Reconstructed hard-palate mucosal epithelium formed in three-dimensional culture was compared to native hard-palate mucosal epithelium and reconstructed oral buccal mucosal epithelium with regard to keratin expression. Artificial hard-palate mucosal epithelium reconstructed in medium with delipidized serum showed a differentiation pattern similar to that of hard-palate epithelium in vivo. The present study also confirmed that keratinocytes derived from hard-palate mucosa are intrinsically different from those of nonkeratinizing oral surfaces.