Low-dose UVA Research Articles

Scleredema treated with broad-band ultraviolet A phototherapy plus colchicine

Scleredema is an uncommon condition characterized by induration of skin. The pathogenesis is not known, although the increased expression of collagen-producing fibroblasts in the skin has been demonstrated. Scleredema has been difficult to treat with scattered reports of success with bath psoralen plus ultraviolet A (PUVA), cream PUVA, UVA1 and others. The use of low-dose broad-band UVA phototherapy was found to be effective in the treatment of morphea. Colchicine has been shown to interfere with collagen synthesis and is used successfully in scleroderma. We report the first case of scleredema that improved markedly with low-dose broad-band UVA plus colchicine treatment.

UVA-induced phenoxyl radical formation: A new cytotoxic principle in photodynamic therapy

Psoralens are regularly used in therapy in combination with ultraviolet A light irradiation (PUVA) to treat skin diseases such as psoriasis, vitiligo, and mycosis fungoides. PUVA therapy is also used within the scope of extracorporeal photopheresis to treat a variety of diseases that have a suspected involvement of pathogenic T cells, including rejection of organ transplants, graft-vs-host disease, cutaneous T cell lymphoma, and autoimmune disorders. Because psoralens are the only photosensitizers used in PUVA therapies and are considered to be responsible for a number of side effects, the identification of alternative drugs is of practical interest. Here we investigated the impact of activated Trolox (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid), a hydrophilic vitamin E analog lacking the phytyl tail, as an alternative photoactivatable agent with T cell cytotoxic properties. Despite the well-known antioxidative capacity of Trolox, we found that at low UVA doses and in the presence of supraphysiological concentration of nitrite, a natural constituent of human skin, this compound selectively enhances radical-mediated cytotoxicity toward T cells but not toward human skin fibroblasts, keratinocytes, or endothelial cells. The cytotoxic mechanism comprises a reaction of Trolox with photo-decomposition products of nitrite, which leads to increased Trolox phenoxyl radical formation, increased intracellular oxidative stress, and a consecutive induction of apoptosis and necrosis in fast proliferating T cells. Thus, the identified UVA/nitrite-induced phenoxyl radical formation provides an opportunity for a new cytotoxic photodynamic therapy.

DNA breakage and cell cycle checkpoint abrogation induced by a therapeutic thiopurine and UVA radiation

The frequency of squamous cell skin carcinoma in organ transplant patients is around 100-fold higher than normal. This dramatic example of therapy-related cancer reflects exposure to sunlight and to immunosuppressive drugs. Here we demonstrate that the interaction between low doses of UVA, the major ultraviolet component of incident sunlight, and 6-TG, a UVA chromophore that is introduced into DNA by one of the most widely-prescribed immunosuppressive drugs, causes DNA single- and double strand breaks (DSB). S phase cells are particularly vulnerable to this DNA breakage and cells defective in rejoining of S-phase DSB are hypersensitive to the combination of low dose UVA and DNA 6-TG. 6-TG/UVA-induced DNA lesions provoke canonical DNA damage responses involving activation of the ATM/Chk2 and ATR/Chk1 pathways and appropriate cell cycle checkpoints. Higher levels of photochemical DNA damage induce a proteasome-mediated degradation of Chk1 and checkpoint abrogation that is consistent with persistent unrepaired DNA damage. These findings indicate that the interaction between UVA and an immunosuppressant drug causes photochemical DNA lesions, including DNA breaks, and can compromise cell cycle checkpoints. These two properties could contribute to the high risk of sunlight-related skin cancer in long-term immunosuppressed patients.

977 THIOTHYMIDINE COMBINED WITH UVA AS A POTENTIAL NOVEL THERAPY FOR BLADDER CANCER

You have accessJournal of UrologyBladder Cancer: Basic Research II1 Apr 2010977 THIOTHYMIDINE COMBINED WITH UVA AS A POTENTIAL NOVEL THERAPY FOR BLADDER CANCER Simon Pridgeon, Gordon Taylor, Keiran O'Toole, Mary Robinson, and Alan Boddy Simon PridgeonSimon Pridgeon London, United Kingdom More articles by this author , Gordon TaylorGordon Taylor Newcastle upon Tyne, United Kingdom More articles by this author , Keiran O'TooleKeiran O'Toole Newcastle upon Tyne, United Kingdom More articles by this author , Mary RobinsonMary Robinson Newcastle upon Tyne, United Kingdom More articles by this author , and Alan BoddyAlan Boddy Newcastle upon Tyne, United Kingdom More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2010.02.1924AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Thiothymidine (TT) is a thymidine analogue which is readily incorporated into cellular DNA. TT is sensitive to UVA (336nm) and on exposure undergoes photochemichal reactions. It is hypothesised that TT incorporated into bladder tumors and subsequently exposed to UVA will form cytotoxic DNA lesions. METHODS MYU-3L and AY27 bladder cancer cell lines were cultured with TT and exposed to UVA. Cytotoxicity was assessed using the SRB assay. Following DNA extraction and digestion, TT incorporation was measured using LC/MS. DNA lesions were characterised using the COMET assay. Bladder tumours were established in Fischer rats by intravesical instillation of tumor cells. TT incorporation into tumor DNA following intravesical or intravenous administration was measured using LC/MS. In vivo efficacy was studied in 5 animals treated with TT and UVA delivery using a 0.4 mm fiber optic. TT uptake into human bladder tumours was studied in an ex-vivo setting. RESULTS TT was measured in DNA of bladder cancer cells replacing 0.1-0.6% thymidine. 100% growth inhibition was observed when AY27 cell lines were incubated with 2uM TT and exposure to 2.5 KJ/m2 UVA. For MYU-3L cells, 100% growth inhibition was observed following incubation with 20 uM TT and exposure to 10 KJ/m2 UVA. Following treatment with TT and UVA, the COMET assay demonstrated the formation of bulky DNA adducts with >50% reduction in Olive tail moments. ProteinaseK treatment suggested these DNA lesions were both DNA-DNA adducts and DNA-protein crosslinks. TT and UVA treatment was associated with an 8-fold increase in caspase 3/7 activity and positive annexin binding suggesting apoptosis. Bladder tumours were successfully established in Fischer rats using MYU-3L cells. TT incorporation was detectable follwing both intravesical and intravenous TT administration. TT replaced 0.0035% of thymidine residues following a 2 hour intravesical TT instillation (16mg) and 0.2 % thymidine replacement was measure following IV TT injection (32 mg). Treatment responses were observed in 60% rats following intravenous TT and intravesical UVA (5 KJ/m2) delivery. TT was detected in 30/40 human bladder tumor resection specimens following 24 hour ex-vivo incubation replacing 0.03 % thymidine. CONCLUSIONS TT has been shown to be incorporated into bladder cancer cell lines. The subsequent exposure to low doses of UVA results in growth inhibition due to the formation of DNA crosslinks. These crosslinks are associated with apoptosis. In vivo and ex vivo treatment suggest that the combination of TT and UVA may offer a novel selective local treatment for bladder cancer © 2010 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 183Issue 4SApril 2010Page: e380 Advertisement Copyright & Permissions© 2010 by American Urological Association Education and Research, Inc.MetricsAuthor Information Simon Pridgeon London, United Kingdom More articles by this author Gordon Taylor Newcastle upon Tyne, United Kingdom More articles by this author Keiran O'Toole Newcastle upon Tyne, United Kingdom More articles by this author Mary Robinson Newcastle upon Tyne, United Kingdom More articles by this author Alan Boddy Newcastle upon Tyne, United Kingdom More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Cyclobutane pyrimidine dimers are photosensitised by carprofen plus UVA in human HaCaT cells

Every year in the UK about 75,000 cases of non-melanoma skin cancer (NMSC) are registered, and about 9500 people are diagnosed with cutaneous melanoma (CM). The main risk factor for these cancers is exposure to sunlight. The effects of light on skin are wavelength dependent, with wavelengths in the UVB waveband (280–315nm) being the most carcinogenic. UVB is directly absorbed by DNA, producing dimeric pyrimidine photoproducts including cyclobutane pyrimidine dimers (CPD) and pyrimidine (6-4) pyrimodone photoproducts (6-4PP). However UVA (315–400nm) can also produce CPD, induce skin tumours in mice, and has been shown to be mutagenic in cell culture. Although the precise role of UVA in human skin cancer remains to be elucidated, it comprises the major portion of solar UV radiation, transmits through window glass and can be delivered in high doses from tanning lamps. Non-steroidal anti-inflammatory drugs (NSAIDs), in particular the 2-aryl propionic acid derivatives, are a well-documented group of photosensitising chemicals producing clinical phototoxic and photoallergic reactions. We have used carprofen, a model compound from this group to see if it could amplify the effects of UVA and contribute to the formation of CPD by UVA. Preliminary work has shown that carprofen combined with low doses of UVA (λmax: 365nm; 5J/cm2) can produce both strand breaks (SB) and CPD in human skin or blood cells. CPD were detected indirectly by both an immunofluorescence method and as T4 endonuclease V sensitive sites in the comet assay. These findings show that compounds other than fluoroquinolones and psoralen derivatives may contribute to CPD formation in skin cells in combination with UVA.

Severely Photosensitive Psoriasis: A Phenotypically Defined Patient Subset

A subset of patients with chronic plaque psoriasis exhibits severely photosensitive psoriasis (PP) with a pronounced seasonal pattern, but the pathomechanism is not understood. We performed two related studies; first, a detailed clinical characterization of PP, and second, a controlled investigation exploring the underlying pathomechanisms through the assessment of disease onset after photoprovocation. Patients with PP (n=20) showed striking female predominance (19F:1M), very low mean age of psoriasis onset (11 years, range 2-24), family history of psoriasis (13/20), a strong HLA-Cw*0602 association (16/17), and a rapid abnormal clinical response to broadband UVA, comprising erythema+/-scaling plaques (17/20). Subsequently, patients with PP (n=10), non-PP (n=9), and healthy volunteers (n=11) were challenged with low-dose broadband UVA on 3 consecutive days, and serial biopsies were taken after 6 hours to 7 days and from unchallenged skin. Histological changes consistent with early psoriasis occurred in 4 of 10 PP patients, but in neither of the control groups, with significant dermal infiltration by neutrophils, CD4+, CD8+, and CD45RO+ cells at 24 h, accompanied by acanthosis. Thus, a phenotypically distinct subset of psoriasis has been characterized. In contrast with earlier assumptions, UV can provoke psoriasiform features rapidly de novo; a role for memory effector T cells is supported in the early phase.

Low‐dose UVA1 phototherapy for proximal and acral scleroderma in systemic sclerosis

Previous studies report the benefit of UVA1 phototherapy in treating acrosclerosis in patients with systemic sclerosis. We carried out a retrospective study to examine the effectiveness of UVA1 phototherapy in scleroderma affecting acral and proximal sites in patients with this disease. Patients with systemic sclerosis (diffuse type, n=5; limited type, n=3) underwent low-dose UVA1 radiation (30-40 J/cm(2)) thrice weekly. In all patients skin lesions improved, demonstrated by a fall in the modified Rodnan skin score ranging from 8 to 18 points in diffuse systemic sclerosis and 6 to 10 points in limited disease. This study would suggest that UVA1 phototherapy is effective for scleroderma affecting proximal and acral sites in patients with systemic sclerosis.

Medium-dose is more effective than low-dose ultraviolet A1 phototherapy for localized scleroderma as shown by 20-MHz ultrasound assessment

Recent studies suggest that ultraviolet (UV) A1 phototherapy is an effective treatment for localized scleroderma (LS); however, the optimum UVA1 dose remains to be determined. We sought to compare the immediate and long-term efficacy of low- versus medium-dose UVA1 phototherapy for plaque-type LS. Three comparable plaques in 16 patients were treated with 20 J/cm2 UVA1, 70 J/cm2 UVA1, or no irradiation. In total, 30 treatments were given. Skin thickness was determined by high-frequency ultrasound examination and clinical scoring. Assessments were done at baseline, immediately after treatment, and 3, 6, and 12 months thereafter. Ultrasound measurement showed a significantly greater reduction of skin thickness with 70 J/cm2 than with 20 J/cm2 at all time points of the study except immediately after UVA1 treatment. The clinical score of the irradiated plaques also decreased substantially but failed to detect a significant difference between the two dose regimens. Our results only pertain to plaque-type LS and are limited by a small sample size. Medium-dose provides for better long-term results than low-dose UVA1 in LS as shown by ultrasound assessment. With clinical scoring, no significant difference between the two UVA1 dose regimens was detected, indicating that ultrasound measurement is a more sensitive method for quantifying treatment-induced skin changes in patients with LS.

Experimental study on the effect of different doses of UVA1 irradiation in the treatment of mouse model of scleroderma.

Objective To compare the changes of skin thickness and collagen content in mouse models of scleroderma after irradiated with different doses of UVA1, so as to seek the suitablc irradiation dose in the treatment for scleroderma. Methods Sixty mice were randomly and equally divided into 6 groups: blank control group (no injection and no irradiation), model control group (injected only and killed 2 days after the last injection), high-dose (HD) UVA1 group (injected with bleomycin and irradiated with UVA1 of 100 J/cm2), medium-dose (MD) UVA1 group (injected with bleomycin and irradiated with UVA1 of 60 J/cm2), low-dose (LD) UVA1 group (injected with bleomycin and irradiated with UVA1 of 20 J/cm2), and negative control group (injected only and killed until the end of irradiation). Experimental mouse models of scleroderma were established by subcutaneous injection of 100 μL bleomycin (BLM) at 400 μg/mL into the back of BALB/c mouse once a day for 4 weeks. Phototherapy was performed 3 times weekly for 10 weeks. Thereafter, skin specimens were obtained from the injected or irradiated back of mice, and subjected to an observation on pathological changes of skin tissue and thickness, as well as the measurement of collagen content. Results There was statistical differences between blank control group and model control group in both the skin thickness (t= 4.945, P<0.001) and collagen content (t=3.712, P<0.01). UVAI phototherapy improved the skin sclerosis and reduced the thickness in mouse models, but significant effect was only observed with HD-UVA1 in both the parameters(both P<0.05). There was significant difference among the 3 groups receiving phototherapy in the changes of skin thickness (F=14.853, P<0.01) and collagen content (F= 6.317, P<0.01), and HD-UVAI was significantly more effective than MD-UVA1 and LD-UVA1. Conclusion High-dose UVAI irradiation could significantly reduce the changes in skin thickness and col- lagen content in mouse model of sclerosis induced by bleomycin,which may be related to its inhibition on collagen fiber proliferation and decrease in collagen content. Key words: Sclerodelma, limited; Ultraviolet ray; Disease models, animal

Effect of ultraviolet radiation on the expression of pp38MAPK and furin in human keratinocyte‐derived cell lines

Ultraviolet radiation (UVR) is known to induce the activation of stress-inflammation signal transduction pathways, and to induce the activity of many proteases in skin cells. It is unknown whether the activation of proteases such as furin is related to changes in the phosphorylation status of p38MAPK. The effect of UVR on immortalized keratinocyte (HaCaT) and squamous cell carcinoma (Colo16) cells was investigated with respect to cell survival, phosphorylation of p38MAPK, and the proprotein convertase, furin. The cells were exposed to either a low or a high dose of UVA and/or UVB and the viability was monitored over 48 h, along with changes in the intracellular expression of p38MAPK and furin. Low-dose UVA (2 kJ/m(2)) and/or UVB (0.2 kJ/m(2)) radiation had no effect on cell viability, except in UVA-irradiated Colo16 cells. High UVA (20 kJ/m(2)) caused a loss of cell viability in HaCaT cells, but not in Colo16 cells. The opposite effect was seen in cells exposed to a high UVB dose (2 kJ/m(2)). The viability of both cell cultures decreased when exposed to high-dose UVA+B radiation. UV irradiation downregulated the expression of phosphorylated p38 (pp38) in HaCaT cells irrespective of the UV dose and type. In Colo16 cells, UV radiation induced pp38 expression in the cells following exposure, with the highest increase in cells exposed to high-dose UVA. The expression of furin in UV-irradiated HaCaT cells was similar to that seen for pp38 expression. In Colo16 cells, UV radiation induced furin expression, with the highest increase seen in cells 24 h after exposure to both high-dose UVB and UVA+B radiation. The results show that there are differences between the effect of UV types and doses on cell function in the keratinocyte-derived cell lines examined in this study. The level of furin expression in Colo16 cells correlated to changes in pp38 levels in the cells following exposure to UV radiation, but not in HaCaT cells. From an improved understanding of the signalling pathways and their downstream events and how these may differ as a result of tumorigenesis, it may enable the development of inhibitors, which may have therapeutic applications.

Low-dose Ultraviolet A1 Phototherapy for Treating Pityriasis Rosea

UVA1 phototherapy has recently demonstrated high levels of efficacy and tolerability for treating a variety of inflammatory and neoplastic skin diseases. The purpose of the present study was to assess the clinical efficacy of UVA1 (340~400 nm) phototherapy for treating pityriasis rosea and to assess the course of the disease after treatment. Fifteen patients with extensive pityriasis rosea were treated with low-dose UVA1 phototherapy (starting at 10~20 J/cm(2) and then it was increased to 30 J/cm(2)). The treatments were given 2~3 times a week until complete clearance of lesions was achieved or until there was partial improvement without further amelioration, in spite of 5 additional treatments. The rate of clearing was monitored by estimating the pityriasis rosea severity (PRSS) score and the pruritus score. The extent of disease (PRSS) in all 15 patients lessened during the study (30.1+/-3.6 vs. 2.0+/-1.6, respectively, p<0.05). The overall reduction of the PRSS showed a significant improvement after the second or third treatment. The pruritus of 12 of 15 patients lessened during the treatment period, and it was unchanged in the remaining 3 patients. The mean previous duration of disease was 11.2+/-4.9 days and this did not interfere with the successful outcome of UVA1 phototherapy. This study shows that UVA1 phototherapy is a useful, well-tolerated treatment option for patients suffering from pityriasis rosea with extensive eruptions and considerable pruritus.

Efficacy of UVA1 phototherapy in 230 patients with various skin diseases

Investigation of the efficacy of ultraviolet (UV) A1 phototherapy on atopic eczema, scleroderma, granuloma annulare, urticaria pigmentosa, prurigo nodularis, lichen sclerosus et atrophicus, T-cell lymphoma, keratosis lichenoides chronica, chronic urticaria and some rare, sclerosing skin diseases. The data of 230 patients treated with low-dose, medium-dose and high-dose UVA1 therapy during 6 years were retrospectively analysed. The mean single dose (J/cm(2)), the mean number of irradiations and the mean total dose (J/cm(2)) were evaluated. The efficacy of phototherapy was assessed by a grading scale and the number of patients was given in percentage for each group. Good therapeutic effects of UVA1 therapy were shown in patients with atopic eczema, scleroderma, lichen sclerosus et atrophicus, keratosis lichenoides chronica, prurigo nodularis and with cutaneous T-cell lymphoma. Positive effects in some patients were seen in the urticaria pigmentosa and granuloma annulare group, no change to slight improvement was seen in most of the patients with rare, sclerosing skin diseases and no effect was seen in the chronic urticaria group. Besides topical and systemic therapy, UVA1 radiation is a good option of treatment in various skin diseases. It is one of the first-line treatments for several sclerotic diseases and it often improves pruritus considerably.

Thiothymidine plus low-dose UVA kills hyperproliferative human skin cells independently of their human papilloma virus status

The thymidine analogue 4-thiothymidine (S(4)TdR) is a photosensitizer for UVA radiation. The UV absorbance spectrum of S(4)TdR and its incorporation into DNA suggests that it might act synergistically with nonlethal doses of UVA to selectively kill hyperproliferative or cancerous skin cells. We show here that nontoxic concentrations of S(4)TdR combine with nonlethal doses of UVA to kill proliferating cultured skin cells. Established cell lines with a high fraction of proliferating cells were more sensitive than primary keratinocytes or fibroblasts to apoptosis induction by S(4)TdR/UVA. Although S(4)TdR plus UVA treatment induces stabilization of p53, cell death, as measured by apoptosis or clonal survival, occurs to a similar extent in both p53 wild-type and p53-null backgrounds. Furthermore, different types of human papilloma virus E6 proteins, which protect against UVB-induced apoptosis, have little effect on killing by S(4)TdR/UVA. S(4)TdR/UVA offers a possible therapeutic intervention strategy that seems to be applicable to human papilloma virus-associated skin lesions.

Tight Control of Matrix Metalloproteinase-1 Activity in Human Skin¶

Chronic ultraviolet irradiation leads to photoaging in human skin, which is associated with degradation of connective tissue. This is partly due to the fibroblast collagenase (matrix metalloproteinase 1 [MMP-1]). Using complementary DNA array technique we demonstrate that after UV irradiation, MMP-1, MMP-3 and the tissue inhibitor of matrix metalloproteinase 1 (TIMP-1) are time-dependently induced on the messenger RNA level in dermal fibroblasts in vitro and in vivo in human buttock skin. This increase in gene expression is paralleled by an increase of latent and active MMP-1 protein after low-dose UV-A exposure in vitro. In vivo the concentration of latent MMP-1 in suction blister fluids peaks 24 h after irradiation with 2 minimal erythema doses of solar simulated radiation. However, only a small proportion of MMP-1 in vitro (5.5 ± 1.5%) and in vivo is active, whereas the majority of MMP-1 remains in its inactive proform. Interestingly, in suction blister fluid the concentration and duration of TIMP-1 expression exceeds that of MMP-1. Taken together, these data indicate that MMP-1 activity is tightly regulated transcriptionally and posttranscriptionally. Furthermore, the pronounced individual differences in all targets investigated provide a possible explanation for the different susceptibility of individuals to UV exposure and, thus, to the clinical features of photodamage.

Failure of physiologic doses of pure UVA or UVB to induce lesions in photosensitive cutaneous lupus erythematosus: implications for phototesting

Phototesting studies in cutaneous lupus erythematosus have yielded variable results, with most trials reporting photo-induction of lesions by both UVA and UVB in substantial numbers of patients. To determine the minimal erythema dose in patients with subacute cutaneous lupus erythematosus (SCLE) and controls. We phototested nine patients with SCLE and 14 skin type-matched controls, using repetitive dosing of UVA1 and UVB, but with filters that removed most of the shorter UVC and longer infrared and visible light. In addition, DNA was isolated from anticoagulated blood to genotype the TNF-alpha 308 region in each patient and control. We were unable to demonstrate a difference in minimal erythema dose (MED) between patients and controls, or any correlation of MED with either TNF genotype or systemic drug therapy for SCLE. In addition, no SCLE skin lesions were induced in the nine patients with either UVA or UVB, and one patient cleared a skin lesion after low-dose UVA1 irradiation. The potential role of wavelengths outside the UVA and UVB range in the photo-induction of cutaneous lupus skin lesions needs to be investigated, and there is a need to standardize phototesting equipment and procedures for patients with cutaneous lupus erythematous.

The Repair Enzyme Peptide Methionine-S-Sulfoxide Reductase Is Expressed in Human Epidermis and Upregulated by UVA Radiation

Recently, we reported that photoaging correlates well with the amount of oxidized protein accumulated in the upper dermis, while protein oxidation levels in the viable epidermis are very low. We hypothesized that this might be due to epidermal expression of the repair enzymes methionine sulfoxide reductases (MSRs). The expression of human methionine sulfoxide reductase A (MSRA) was investigated in HaCaT cells, primary human keratinocytes, and in human skin. High MSRA mRNA and protein levels as well as MSR activity were found in cultured human keratinocytes. MSRA was expressed in human epidermis, as shown by immunohistochemistry in healthy human skin. Repetitive in vivo exposure of human skin to solar-simulated light on 10 consecutive days (n=10 subjects) significantly increased epidermal MSRA expression. To further assess the functional relevance of the enzyme, its expression in response to UVB, UVA, and H(2)O(2) was investigated in HaCaT cells. While UVB lowered protein expression of MSRA, an upregulation was observed in response to low doses of UVA and H(2)O(2). In summary, MSRA represents the only enzyme so far identified in human skin that is capable of repairing oxidative protein damage. In addition to melanogenesis and DNA repair systems, a wavelength-specific activation of epidermal MSRA may be involved in epidermal photoprotection.

A trial of low-dose UVA1 phototherapy for two patients with recalcitrant discoid lupus erythematosus

A trial of low-dose UVA1 phototherapy for two patients with recalcitrant discoid lupus erythematosus

A randomized controlled study of low-dose UVA1, medium-dose UVA1, and narrowband UVB phototherapy in the treatment of localized scleroderma

In previous trials, UV therapy has been demonstrated to be effective in the treatment of localized scleroderma (LS). To date, a randomized comparison study to evaluate the efficacy and safety of different, commonly used phototherapeutic modalities in LS is still outstanding. The aim of this study was to compare the safety and efficacy of low-dose (LD) UVA1, medium-dose (MD) UVA1, and narrowband (NB) UVB phototherapy in the treatment of LS. Sixty four patients with LS were consecutively included in a prospective, open, randomized controlled 3-arm study. Severity of LS was determined by means of a clinical score, and clinical improvement was also monitored by histopathologic analysis and 20-MHz ultrasound. A total of 27 patients were treated with LD UVA1 (20 J/cm2), 18 patients received MD UVA1 (50 J/cm2), and 19 patients were treated with NB UVB dependent on their skin type. Phototherapy was performed 5 times weekly for 8 weeks. Two of the 64 patients included in this trial discontinued therapy. Skin status significantly improved in all patients who finished the treatment protocol, resulting in a reduction of the clinical score in all groups (LD UVA1, 7.6-5.0 [P < .001, 95% confidence interval 1.6-3.4]; MD UVA1, 11.1-6.6 [P < .001, 95% confidence interval 2.5-6.2]; NB UVB, 7.3-4.9 [P < .001, 95% confidence interval 1.6-3.2]). The reduction of the score was accompanied by an improvement of the visual analog scale for itching and tightness, histologic score, and 20-MHz ultrasound. MD UVA1 was significantly more effective than NB UVB (P < .05). There were no significant differences between LD UVA1 and NB UVB and the former and MD UVA1 (P > .05). We had a relatively small study sample and nonblinded assessment of primary outcome. Phototherapy, as previously reported in several noncontrolled trials, is an effective therapeutic option in LS, with a favorable risk/benefit ratio. UVA1 phototherapy should be considered among the first approaches in the management of LS.

Low UVA doses activate the transcription factor NFAT in human fibroblasts by a calcium–calcineurin pathway

UVA radiation induces an inflammatory response as observed in erythema, and the cytokine genes involved in this response are under the control of the transcription factor NFAT (nuclear factor of activated T lymphocytes). The effects of UVA on NFAT DNA binding activity were investigated in cultured human fibroblasts. A dose-dependent increase was observed within the range of 0.6–4.5 J/cm 2 UVA. Beyond this value, the activity decreased and a value of 60% of control was found at 13.5 J/cm 2. The enhancement of NFAT activity was transient and peaked 45 min after irradiation. Furthermore, immunoblot analysis demonstrated a nuclear translocation of NFAT under low UVA doses. Concomitantly, as assessed by the fluorescent probe Fluo3, UVA induced an increase in intracellular free calcium, with a maximum increase found at 9 J/cm 2. The UVA-induced activation of NFAT was prevented by the intracellular calcium trapping drug BAPTA, whereas the extracellular calcium chelator EGTA had no significant effect. In addition, the calcineurin inhibitors cyclosporin A and FK506 both prevented the UVA-induced NFAT activation. Furthermore, the antioxidant vitamin E prevented the UVA-induced increase in both intracellular free calcium and NFAT binding activity. Finally, the cytotoxicity of UVA was enhanced in the presence of the inhibitors cyclosporin and FK506, suggesting that the activation of NFAT might play a protective role after the UVA-induced oxidative stress. These results demonstrate that UVA activates the calcium–calcineurin signaling pathway of NFAT activation, that the calcium ions are mainly released from intracellular stores, and that the increase in calcium is, at least partially, due to the oxidative stress generated under UVA. Because NFAT regulates several genes implicated in the inflammatory response, the enhancement of NFAT activity by low UVA doses might be interpreted in view of the proinflammatory action of solar radiation.

Vitamin E Delivery to Human Skin by a Rinse-Off Product: Penetration of α-Tocopherol versus Wash-Out Effects of Skin Surface Lipids

α-Tocopherol, the major biologically active form of vitamin E, represents a frequently added lipophilic compound of skin care products. Despite its emerging use in rinse-off formulations, little is known on its efficacy with respect to its deposition or its antioxidant potential in human skin. The objective of this study was to investigate whether the single use of an α-tocopherol-enriched rinse-off product provides effective deposition of α-tocopherol on human stratum corneum. To test this, forearm skin of 13 volunteers was washed either with an α-tocopherol-enriched rinse-off product (test product, TP) or with an α-tocopherol-free vehicle control (control product, CP) (contralateral arm) using a standardized wash protocol. Thereafter, skin surface lipids were extracted with pure ethanol after the wash procedure as well as after 24 h. Additionally, one group of volunteers was subjected to irradiation of their forearms with low-dose UVA (8 J/cm²) prior to lipid extraction. Skin lipid extracts were analyzed by high performance liquid chromatography using electrochemical detection for vitamin E and UV detection for squalene (SQ) and squalene monohydroperoxide. The results of this in vivo study demonstrated that (1) while CP treatment lowers, TP treatment strongly increases α-tocopherol levels of skin barrier lipids; (2) increased vitamin E deposition levels were maintained for a period of at least 24 h, and (3) TP treatment significantly inhibited photooxidation of SQ. In conclusion, the use of α-tocopherol-enriched rinse-off products may help to maintain the integrity of the skin barrier by providing protection against photooxidative stress at the level of skin surface lipids.