Ultraviolet A1 (340-400 nm) phototherapy for scleroderma in systemic sclerosis

BACKGROUND: The presence of an inflammatory infiltrate consisting of helper T cells and a dysregulated matrix metabolism leading to excessive deposition of collagen are two pathogenetic factors responsible for the developments of fibrosis and sclerosis in patients with systemic sclerosis. In previous studies, ultraviolet A1 (UVA1) radiation phototherapy was shown to deplete skin-infiltrating T cells through the induction of T-cell apoptosis and to up-regulate the expression of matrixmetalloproteinase-1 (collagenase-1) in dermal fibroblasts. OBJECTIVE: Our purpose was to determine whether UVA1 phototherapy is effective for systemic sclerosis. METHODS: Lesional skin on the forearms of patients with systemic sclerosis (diffuse type, n =3; limited type, n =1) was exposed to medium-dose UVA1 radiation (60 J/cm(2)) daily. RESULTS: In all patients studied, UVA1 phototherapy-treated skin lesions were markedly softened after 9 to 29 exposures. Clinical improvement was associated with an increase in (1) joint passive range of motion values (P <.05), (2) skin temperature (thermography, P <.05), and (3) cutaneous elasticity (cutaneous elastometry, P <.05). Histologic evaluation of skin specimens obtained before and after UVA1 phototherapy revealed loosening of collagen bundles and the appearance of small collagen fibers. CONCLUSION: These studies indicate that UVA1 phototherapy is effective for patients with systemic sclerosis.     

Ultrastructural changes induced in cutaneous collagen by ultraviolet-A1 and psoralen plus ultraviolet A therapy in systemic sclerosis

In the present study, we examined the ultrastructural alterations in collagen fibrils clinically softened by ultraviolet-A1 (UVA1, 340-400 nm) therapy and psoralen plus long-wave ultraviolet (PUVA) therapy and compared collagen fibril diameters in four patients with systemic sclerosis (SSc). In skin sclerosis, the dermis is compacted from the epidermal layer to the sweat glands, and the collagen bundles are thicker with decreased space between them. We obtained skin specimens before and after UVA1 or PUVA therapy, and compared cutaneous alterations in one diffuse-type patient and one limited-type patient following UVA1 therapy, and in two diffuse-type patients following PUVA treatment. Ultramicroscopic analysis revealed that UVA1 treatment decreased the diameter of the broad collagen fibrils, mainly in the upper reticular layer. PUVA induced similar alterations in the collagen fibrils, extending to the upper and middle reticular layers. PUVA therapy induced alterations in collagen fibril diameter in deeper layers than did UVA1 therapy, which might be related to the direct action of UV light and the depth of the light penetration. In three of four patients, collagen fibril diameter decreased, collagen fibril thickness equalized, and new, thin fibrils developed among the collagen fibrils, suggesting that collagen degradation and synthesis underlie the alterations induced by UVA1 and PUVA phototherapies.     

Induction of matrix metalloproteinase‐1 by small interfering RNA targeting connective tissue growth factor in dermal fibroblasts from patients with systemic sclerosis

Please cite this paper as: Induction of matrix metalloproteinase‐1 by small interfering RNA targeting connective tissue growth factor in dermal fibroblasts from patients with systemic sclerosis. Experimental Dermatology 2010; 19 : e111–e116. Abstract: We aimed to evaluate the effect of small interfering RNA (siRNA) targeting CTGF on extracellular matrices (ECMs) metabolism in normal and SSc fibroblasts. Normal and SSc fibroblasts were transfected with CTGF‐specific siRNAs to silence CTGF synthesis. After silencing CTGF, production of type I collagen and matrix metalloproteinase (MMP)‐1 by fibroblasts stimulated with TGF‐β was examined. Then quantitative analyses of protein production or mRNA expression of type I collagen, MMP‐1,‐2,‐9 and tissue inhibitor of metalloproteinase (TIMP)‐1 with TGF‐β stimulation were carried out. Furthermore, after silencing CTGF, proliferations of normal and SSc fibroblasts were investigated. CTGF‐specific siRNA significantly reduced CTGF production. The production of type I collagen was significantly reduced by CTGF silencing in normal fibroblasts. The CTGF silencing significantly increased the production of MMP‐1 and decreased the production of TIMP‐1 in SSc fibroblasts. The mRNA expression of MMP‐1 was increased in CTGF‐silenced SSc fibroblasts, but not in normal fibroblasts. There were no significant changes in the production or mRNA expression of other ECM‐related genes in normal and SSc fibroblasts. Fibroblast proliferations were suppressed by CTGF silencing in normal and SSc fibroblasts. Our data showed that MMP‐1 was increased by CTGF‐specific siRNA transfection only in SSc fibroblasts. RNAi targeting CTGF could be a novel therapeutic strategy for SSc.     

Serum amyloid A1 secreted from UV‐irradiated keratinocytes induces matrix metalloproteinase‐1 in fibroblasts through toll‐like receptor 4

Ultraviolet (UV) irradiation on skin triggers photoageing‐related phenotypes such as formation of wrinkles. UV ray upregulates matrix metalloproteinase‐1 (MMP‐1), which in turn degrades extracellular matrix proteins, mostly collagens. Serum amyloid A1 (SAA1) is an acute‐phase protein of which plasma concentration increases in response to inflammation. Although the expression of SAA1 in the skin was reported, its function in the skin is yet to be studied. In this research, we found that the expression of SAA1 was increased in acute UV‐irradiated buttock skin and photoaged forearm skin in vivo. UV irradiation also increased SAA1 in normal human epidermal keratinocytes (NHEK), and treatment of recombinant human SAA1 (rhSAA1) induced MMP‐1 in normal human dermal fibroblasts (NHDF) but not in NHEK. Next, we demonstrated that NHDF treated with UV‐irradiated keratinocyte‐conditioned media showed the increased MMP‐1 expression; however, this increase of MMP‐1 in NHDF was inhibited by knockdown of SAA1 in NHEK. In addition, knockdown of Toll‐like receptor 4 (TLR4) inhibited rhSAA1‐induced MMP‐1 expression in NHDF. Taken together, our data showed that UV‐induced SAA1 production in NHEK, and this secreted SAA1 induced MMP‐1 expression in NHDF in a paracrine manner through TLR4 signalling pathway. Therefore, our results suggest that SAA1 can be a potential mediator for UV‐induced MMP‐1 expression in human skin.     

Immunohistochemical expression of matrix metalloproteinase-2 and -9 in melanocytic nevi is altered by ultraviolet B

BACKGROUND: Ultraviolet B (UVB) radiation can cause morphological and biological alterations similar to those of melanoma in situ in irradiated melanocytic nevi. matrix metalloproteinase (MMP-2) and -9 appear to be involved with tumour invasion, the formation of metastases and neoangiogenesis in melanomas. The effects of UVB on the immunohistochemical expression of gelatinases in different cell types in melanocytic nevi have not been completely studied. PURPOSE: Evaluate the effects of UVB on the immunohistochemical expression of MMP-2 and -9 in different cell types in melanocytic nevi. METHODS: Forty-two melanocytic nevi had one half irradiated with 2 MEDs of UVB and were excised 1 week later. Three different observers compared the intensity of the immunohistochemical expression of gelatinases in keratinocytes, melanocytes, endothelial cells and fibroblasts on the irradiated (IS) and non-irradiated sides (NIS). RESULTS: All the cell types showed an increase in the expression of MMP-2 on the IS, especially the epidermal melanocytes. No significant increase in the expression of MMP-9 in keratinocytes was detected on the IS; significant increase was observed in all the remaining cells. CONCLUSIONS: One single irradiation of UVB increases the immunohistochemical expression of gelatinases in almost all evaluated cell lines, with the exception of MMP-9 in keratinocytes.     

Changes in collagen I and collagen III metabolism in patients with generalized atopic eczema undergoing medium-dose ultraviolet A1 phototherapy

Fourteen patients suffering from acute, exacerbated atopic eczema were screened for changes in collagen I and collagen III metabolism in serum (n = 11), urine (n = 11) and skin biopsies (n = 9) before and after medium-dose ultraviolet (UV) A1 phototherapy (15 exposures of 50 J/cm2 over a 3-week period, total dose 750 J/cm2). Mature collagen I and, to a lesser extent, mature collagen III were found to be decreased after the therapy in skin samples from the irradiated patients. As markers of collagen I degradation, the cross-links pyridoline and deoxypyridoline were analysed in urine using high-performance liquid chromatography. Both cross-links were found to be mildly increased after UVA1 phototherapy, without reaching statistical significance. As markers of de novo collagen synthesis we screened for the procollagen I-carboxyterminal peptide (PICP) and procollagen III-aminoterminal peptide (PIIINP) levels in serum and skin. The ratio of PICP to PIIINP in serum dropped significantly after the UVA1 phototherapy, suggesting a different impact of UVA1 on the two collagens. These findings were paralleled by a diminished ratio of PICP to PIIINP in tissue samples. Staining for matrix metalloproteinase 1 (MMP-1) and its specific counterpart, tissue inhibitor of MMP-1 (TIMP-1), showed slight increases for both proteins by therapeutic UVA1; this was also seen in serum for TIMP-1 but not MMP-1. In our study, high-energy UVA1 doses induced changes of the skin collagens in patients with atopic eczema which are measurable by their metabolites in serum and urine.     

Immunoprotective haem oxygenase induction by ultraviolet A (320-400 nm) radiation in the mouse is inhibited in interferon-gamma null mice

BACKGROUND: A protective role for the ultraviolet (UV) A waveband against immunosuppression induced by UVB (280-320 nm) radiation has been identified. The mechanism for UVA immunoprotection was found to involve two apparently unrelated mediators, the T-helper-1-associated proinflammatory cytokine interferon (IFN)-gamma and the UVA-induced redox-regulated stress protein, haem oxygenase (HO). OBJECTIVES: To identify a relationship between these two immune regulators. METHODS: The HO response to UVA radiation in the skin and liver was examined in mice with a targeted disruption of the IFN-gamma gene, known to be unresponsive to UVA photoimmunoprotection. Results IFN-gamma null mice did not respond to UVA irradiation with the normal upregulation of HO activity in either the irradiated skin or the liver. Injection of these mice with recombinant IFN-gamma previously shown to restore the UVA-photoimmunoprotective effect, here partially and dose-responsively restored their ability for induction of HO activity in both skin and liver following UVA irradiation. CONCLUSIONS: IFN-gamma appears to be a prerequisite for the immunoprotective induction of HO, although other mediators may also be involved. The UVA responsiveness of HO in an internal organ such as the liver suggests the existence of a soluble UVA-induced mediator from the skin, which may be IFN-gamma.     

Expression of extracellular matrix protein 1 (ECM1) in human skin is decreased by age and increased upon ultraviolet exposure

BACKGROUND: The extracellular matrix protein 1 (ECM1) is expressed in human skin and plays an important role in its normal structure and function. In the rare genetic skin disease lipoid proteinosis, which is characterized by a loss-of-function mutation in the ECM1 gene, skin areas habitually exposed to the sun may show a more severely scarred and photoaged appearance. However, no data are available on the possible involvement of ECM1 expression in intrinsic and extrinsic skin ageing. OBJECTIVES: We hypothesized that ECM1 expression in human skin is regulated by age- and ultraviolet (UV)-dependent mechanisms. METHODS: Skin biopsies from 12 patients with histologically confirmed solar elastosis, from non-UV-exposed sites of 12 age-matched controls and 12 young subjects were analysed. To evaluate the influence of acute UV exposure, buttock skin of 10 healthy subjects was irradiated repetitively on 10 days with a solar simulator and compared intraindividually with non-UV-treated contralateral sites. The expression of ECM1 was investigated by immunohistochemistry using an ECM1 antibody detecting ECM1a and ECM1c isoforms. Semiquantitative analysis of staining intensity was carried out by densitometric image analysis. RESULTS: In normal human skin ECM1a and ECM1c are expressed mainly in the basal cell layers of epidermal keratinocytes and in dermal vessels. For the first time, an expression in the outer root sheath of hair follicles, in sebaceous lobules and epithelium of sweat glands is described. Intrinsically (UV-protected) aged skin shows a significantly reduced expression in basal and upper epidermal cell layers compared with young skin. In photoaged skin, expression is significantly increased within the lower and upper epidermis compared with age-matched UV-protected sites. Importantly, after acute UV exposure in young healthy subjects expression of ECM1 is markedly increased in both lower and upper epidermal cell layers. CONCLUSIONS: This is the first study to demonstrate a regulation of ECM1 expression in human skin by age and UV exposure. These data suggest that ECM1 expression may represent a cutaneous stress response to acute and chronic UV irradiation.     

Epidermal growth factor-induced matrix metalloproteinase-1 expression is negatively regulated by p38 MAPK in human skin fibroblasts

Background

Many extracellular stimuli, including epidermal growth factor (EGF), are known to induce MMP-1 expression. Recently, several reports have shown that ERK activity plays an important role in EGF-induced MMP-1 expression. However, EGF is also known to activate many signaling pathways in addition to the ERK pathway, but the roles of these pathways during the induction of MMP-1 by EGF are unclear.

Objective

We investigated the role of JNK, p38 MAPK, and PI3K/Akt pathways in EGF-induced MMP-1 expression in human skin fibroblasts. Then, we further explored the inhibitory effect of p38 MAPK pathway on EGF-induced MMP-1 expression and studied the molecular mechanisms involved in the processes.

Methods

Human skin fibroblasts were pretreated with various chemical inhibitors or small interfering RNA (siRNA) at the indicated concentrations and then treated with EGF, TNF-alpha, or IL-1beta for the indicated times. Protein and mRNA levels of various target molecules were assessed by Western blotting and quantitative real-time PCR, respectively.

Results

We found that EGF-induced MMP-1 expression was positively regulated by JNK as well as ERK but negatively regulated by p38 MAPK in human skin fibroblasts. On the other hand, the PI3K/Akt pathway did not significantly affect MMP-1 induction by EGF. Then we found that the inhibition of p38 MAPK pathway specifically increased the MMP-1 expression stimulated by EGF but not by TNF-alpha or IL-1beta, indicating that the effect of p38 MAPK on MMP-1 expression may be stimulus-type specific in human skin fibroblasts. In addition, the inhibitory effect of p38 MAPK on EGF-induced MMP-1 expression was shown to be mainly mediated by p38-alpha MAPK. Our further studies showed that the inhibition of p38 MAPK but not PI3K specifically increased EGF-induced ERK and JNK activations, and that the augmentation of EGF-induced MMP-1 expression by p38 MAPK inhibition was significantly attenuated by inhibiting the activities of ERK and/or JNK.

Conclusions

Our results indicate that EGF-induced MMP-1 expression is differentially regulated by the JNK, p38 MAPK, and PI3K/Akt pathways, and suggest that p38 MAPK negatively regulates EGF-induced MMP-1 expression by suppressing the activations of ERK and JNK.     

Curcumin inhibits UVB‐induced matrix metalloproteinase‐1/3 expression by suppressing the MAPK‐p38/JNK pathways in human dermal fibroblasts

Curcumin (diferuloylmethane) is a polyphenol derived from turmeric (Curcuma longa), which is commonly used as a spice. Recent studies have shown that curcumin has a wide range of pharmacological activities, including anticarcinogenic, antioxidant, anti‐inflammatory and antiangiogenic activities. However, the antiphotoageing effects of curcumin have yet to be characterized. In this study, we investigated the inhibitory effects of curcumin on matrix metalloproteinase (MMP)‐1 and MMP‐3 expression in human dermal fibroblast cells. Western blot analysis revealed that curcumin inhibited ultraviolet (UV) B‐induced MMP‐1 and MMP‐3 expression. Furthermore, curcumin significantly blocked UVB‐induced reactive oxygen species generation in fibroblasts. Curcumin treatment significantly blocked the UVB‐induced activation of nuclear factor (NF)‐κB and activator protein (AP)‐1. Additionally, curcumin strongly repressed the UVB‐induced phosphorylation of p38 and c‐Jun N‐terminal kinase. Curcumin prevented UVB‐induced MMP expression through mitogen‐activated protein kinase/NF‐κB inhibition and AP‐1 activation. In conclusion, curcumin may be useful for preventing and treating skin photoageing.     

雌二醇对体外培养的人皮肤成纤维细胞基质金属蛋白酶-1基因表达的影响

绝经后女性皮肤老化的加速使人们很早就注意到了雌激素在皮肤老化中的作用.研究显示,在光老化和正常皮肤中,局部使用雌激素可以增加皮肤组织中胶原的含量,改善皮肤的厚度和弹性,本试验通过观察雌二醇对体外培养的人皮肤成纤维细胞基质金属蛋白酶-1(matrix metalloproteinase-1,MMP-1)mRNA水平的影响,探讨雌二醇减缓皮肤老化的机制.     

Merkel cell carcinoma arising in immunosuppressed patients treated with high-dose ultraviolet A1 (320-400 nm) phototherapy: a report of two cases

Merkel cell carcinoma (MCC) is an aggressive neuroendocrine tumour of the skin. Though immunodeficiency is the most relevant risk factor, ultraviolet (UV) radiation is also involved, but as of yet we do not know the action spectrum, pattern or dose which would produce a dangerous exposure. A retrospective study of two immunosuppressed patients who developed MCC during, or soon after a treatment cycle with high dose UVA1 exposures was conducted, in order to understand wether repeated exposures to suberythemogenic UVA1 radiation may have a cancerogenic activity provoking MCC in immunosuppressed patients.     

5‐Methoxypsoralen plus ultraviolet (UV) A is superior to medium‐dose UVA1 in the treatment of severe atopic dermatitis: a randomized crossover trial

Background Ultraviolet (UV) A1 and psoralen plus UVA (PUVA) are effective treatment options for severe atopic dermatitis (AD); however, their relative efficacy has not yet been determined in a head‐to‐head study. Objectives To compare UVA1 and oral 5‐methoxypsoralen (5‐MOP) plus UVA with respect to efficacy, tolerability and duration of response in patients with severe generalized AD. Methods Forty patients were included in this randomized observer‐blinded crossover trial. The patients received either 15 exposures to medium‐dose UVA1 as the first treatment and, in cases of relapse, another 15 exposures to 5‐MOP plus UVA as the second treatment, or vice versa. All patients were followed until 12 months after discontinuation of the last treatment. The SCORAD score was determined by a blinded investigator at baseline, after 10 and 15 treatments each and during the follow‐up period. In addition, all adverse events were recorded during the whole study period. Results Twenty‐three patients completed the crossover treatment. Both phototherapies resulted in clinical improvement; however, PUVA reduced the baseline SCORAD score to a significantly greater extent than UVA1 (mean ± SD 54·3 ± 25·7% vs. 37·7 ± 22·8%; P = 0·041). The median length of remission was 4 weeks (interquartile range 4–12) after UVA1 and 12 weeks (interquartile range 4–26) after PUVA therapy (P = 0·012). Conclusions PUVA provides a better short‐ and long‐term response than medium‐dose UVA1 in patients with severe AD.