GRIM-19在银屑病皮损中的表达及维A酸对其影响的研究

目的研究GRIM-19在银屑病皮损中的表达水平及维A酸对其的影响。方法采用免疫组化法检测银屑病皮损中GRIM-19的表达,观察维A酸治疗对其表达的影响。结果正常皮肤组织、银屑病边缘皮损和中间皮损中GRIM-19蛋白的表达强度逐渐减弱,差异有统计学意义(C2=49.18,P 0.05);维A酸治疗前、治疗2周、4周后皮损中GRIM-19表达强度逐渐增强,差异有统计学意义(C2=51.78,P 0.05)。结论 GRIM-19在银屑病皮损中表达下降,维A酸可能通过上调GRIM-19来调控角质形成细胞的增殖凋亡,从而治疗银屑病。     

维A酸受体mRNA在寻常性银屑病外周血单一核细胞中表达水平的研究

目的　探讨寻常性银屑病患者外周血单一核细胞中维A酸受体 (RARα、RARγ、RXRα)mRNA的表达情况。方法　用RT PCR法对比研究了 2 0例寻常性银屑病患者和 10例正常对照组外周血单一核细胞中维A酸受体mRNA表达情况。结果　寻常性银屑病患者外周血单一核细胞中的维A酸受体mRNA的表达水平与正常对照组无差异。结论　用维A酸治疗寻常性银屑病过程中 ,免疫细胞是否为维A酸的作用靶细胞还不能确定。     

RXR-α mRNA 在寻常型银屑病皮损中的表达

目的:检测维A酸核内受体α(RXR-α)在寻常型银屑病皮损及非皮损皮肤中的表达。方法:采用RT-PCR对28例寻常型银屑病皮损及非皮损皮肤中RXR-α mRNA的表达进行检测,并以30例正常人皮肤作为对照。结果: 银屑病皮损中RXR-α mRNA的表达显著低于非皮损处皮肤(P0.001)和正常人皮肤(P0.001),进行期皮损处RXR-α mRNA的表达比静止期皮损表达显著降低(P0.01),但非皮损皮肤的表达与正常人皮肤无显著性差异(P0.05)。结论: RXR-α在银屑病的发病中可能起一定作用。     

维A酸衍生物ECPIRM对维A酸核受体的影响及小鼠皮肤刺激反应

目的 探讨维A酸衍生物ECPIRM对维A酸核受体的影响,评估ECPIRM对小鼠皮肤的红斑、脱屑等刺激反应.方法 10μmol/L ECPIRM和全反式维A酸(ATRA)作用于SCL-1细胞24 h,用蛋白免疫印迹法和实时荧光定量PCR法分别检测维A酸受体(RARα 、RARβ、RARγ和RXRα)的蛋白和mRNA表达变化.用实时荧光定量PCR检测维A酸受体RAR激活通路的靶基因细胞色素P450家族成员26A1和他扎罗汀诱导基因1 (TIG1)的mRNA表达变化.BALB/c小鼠剃毛后外涂ECPIRM凝胶,以等摩尔浓度的全反式维A酸乳膏为对照,观察小鼠皮肤刺激反应.结果 ATRA作用后,RARα、RARβ、RARγ的蛋白和mRNA表达明显增高,与对照组比较差异有统计学意义(P＜0.05).CYP26A1和TIG1的mRNA表达分别增加到25.49倍和3.88倍,差异有统计学意义(P＜0.01).但ECPIRM作用后并不增加核受体RARα、RARβ、RARγ及RXRα的蛋白表达;RARα、RARβ、RARγ的mRNA表达变化差异无统计学意义(P＞0.05);RAR靶基因CYP26A1和TIG1的mRNA表达变化差异无统计学意义(P＞0.05).BALB/c小鼠外用全反式维A酸乳膏后2d出现明显的红斑、脱屑反应,用药5d达高峰.而连续外用0.075％ECPIRM凝胶21d,小鼠一直未出现红斑、脱屑反应.结论 ECPIRM不激活经典的维A酸受体通路,未出现ATRA样皮肤刺激反应.     

维A酸对角质形成细胞NF-кB及细胞因子的影响

目的探讨维A酸药物对角质形成细胞的影响及核因子调控机制,为药物治疗银屑病提供理论依据。方法从银屑病患者外周血分离单一核细胞(PBMCs),与角质形成细胞系HaCat混合培养,用维A酸预处理HaCat细胞,以雷公藤为对照,利用流式细胞仪分析培养体系及HaCat各自的NFкB表达,ELISA测上清液中IL8、ICAM1含量。结果银屑病患者培养体系及HaCat中NFкB和细胞因子的水平均高于健康对照组(P<0.01),经维A酸预处理HaCat后,可抑制核因子的表达,与雷公藤比较差异无显著性。结论维A酸可能通过下调NFкB的活化而改善银屑病的症状,同时提示抑制NFкB活性的药物可能有助于银屑病的治疗。     

连续外用维A酸皮肤刺激反应中的维A酸结合蛋白mRNA的表达

目的: 检测在连续外用维A酸引起的皮肤刺激反应中小鼠皮肤维A酸结合蛋白mRNA表达水平.方法: 连续外用0.1%维A酸和基质,用RT-PCR方法检测Balb/C小鼠皮肤中维A酸结合蛋白(CRABP I、CRABP II)mRNA的表达水平.结果: 外用0.1%维A酸霜,皮肤中CRABP II mRNA表达水平在用药第一天呈一过性升高.连续用药,CRABP II mRNA表达水平稳定升高而不受每天用药前后的影响,第6天达次高峰,第9天达高峰,第12天降至次高峰,一直到用药24天,均维持在次高峰水平.而CRABP I mRNA表达水平在用药期间未见改变.维A酸霜基质对这两种蛋白mRNA的表达没有影响.结论: 外用维A酸霜引起的一过性皮肤刺激反应可能是由CRABP II介导.     

维A酸对角质形成细胞NF-κB及细胞因子的影响

目的探讨维A酸药物对角质形成细胞的影响及核因子调控机制,为药物治疗银屑病提供理论依据.方法从银屑病患者外周血分离单一核细胞(PBMCs),与角质形成细胞系HaCat混合培养,用维A酸预处理HaCat细胞,以雷公藤为对照,利用流式细胞仪分析培养体系及HaCat各自的NF-κB表达,ELISA测上清液中IL-8、ICAM-1含量.结果 银屑病患者培养体系及HaCat中NF-κB和细胞因子的水平均高于健康对照组(P＜0.01),经维A酸预处理HaCat后,可抑制核因子的表达,与雷公藤比较差异无显著性.结论维A酸可能通过下调NF-κB的活化而改善银屑病的症状,同时提示抑制NF-κB活性的药物可能有助于银屑病的治疗.     

寻常性银屑病患者皮损中维A酸受体αmRNA的表达

目的 探讨维A酸受体αmRNA在寻常性银屑病皮损中的表达状况。方法 应用RT-PCR方法检测20例寻常性银屑病患者皮损部位和10例正常人表皮中维A酸受体αmRNA的表达情况。结果 维A酸受体αmRNA的表达在寻常性银屑病表皮中较正常人低,且差异有显著性(P<0.01)。结论 维A酸受体αmRNA的表达降低可能和银屑病发病有关。     

维A酸在皮肤科临床应用的现状与进展

目前将维A 酸类药物按其结构分为3 类.维A 酸一般是通过其受体发挥药理作用,但也存在非受体机制.其参与调控表皮细胞增殖、分化、凋亡,免疫调节,抑制皮脂腺分泌等生物学效应.维A 酸用于银屑病、痤疮、皮肤T 淋巴细胞瘤、皮肤光老化、角化性皮肤病及表皮肿瘤等多种皮肤病的治疗.维A 酸的主要不良反应是致畸和胚胎毒性,儿童长期...     

维A酸对银屑病患者外周血T淋巴细胞增殖及JAK3表达的影响

目的探讨第三代维A酸(芳维A酸氨丁三醇)和第二代维A酸(依曲替酸)对银屑病患者T淋巴细胞增殖的影响及其机制。方法抽取银屑病患者外周血,分离T淋巴细胞,经不同浓度药物处理后,台盼蓝染色检测细胞活力,用改良MTT法检测淋巴细胞的增殖能力;分别用Real-time PCR和蛋白印迹方法检测JAK3,STAT5的mRNA和蛋白表达水平。结果芳维A酸氨丁三醇与依曲替酸在10-9~10-6浓度范围内,均对银屑病患者外周血T淋巴细胞的增殖有抑制作用,且呈剂量依赖性,芳维A酸氨丁三醇比依曲替酸抑制作用更明显;两种药物均可下调银屑病患者T淋巴细胞JAK3基因的表达,且芳维A酸氨丁三醇的下调作用更显著,但STAT5蛋白表达无变化。结论芳维A酸氨丁三醇和依曲替酸可明显抑制银屑病患者外周血T淋巴细胞的增殖,其机制可能与下调JAK3表达有关。     

Topical treatment with CYP26 inhibitor talarozole (R115866) dose dependently alters the expression of retinoid-regulated genes in normal human epidermis

Background  An alternative approach to retinoid therapy is to inhibit the cytochrome P450 (CYP)-mediated catabolism of endogenous all- trans retinoic acid in the skin by applying retinoic acid metabolism blocking agents such as talarozole (R115866).
Objectives  To study the effects of topical talarozole on retinoid biomarkers in normal skin in a randomized phase I trial.
Methods  Gels containing talarozole (0·35% or 0·07%) and vehicle were applied once daily for 9 days on either buttock of 16 healthy volunteers. Epidermal shave biopsies (for mRNA analysis) and punch biopsies (for histology and immunofluorescence analysis) were collected from the treatment areas. Genes encoding the following were studied by quantitative real-time polymerase chain reaction: cellular retinoic acid binding protein 2 (CRABP2), cytokeratins (KRT2 and KRT4), CYP26A1, CYP26B1, CYP26C1 and CYP2S1, two enzymes in the retinol metabolism (retinal dehydrogenase-2 and retinol acyltransferase) and two proinflammatory cytokines [interleukin (IL)-1α and tumour necrosis factor-α].
Results  Talarozole treatment increased the mRNA expression of CRABP2, KRT4, CYP26A1 and CYP26B1 dose dependently, and decreased the expression of KRT2 and IL-1α compared with vehicle-treated skin. No mRNA change in retinol-metabolizing enzymes was obtained. There was no induction of epidermal thickness or overt skin inflammation in talarozole-treated skin. Immunofluorescence analysis confirmed an upregulation of KRT4 protein, but no upregulation of CYP26A1 and CYP26B1 expression was detected.
Conclusions  Talarozole influences the biomarker pattern consistently with increased retinoic acid stimulation. The low irritancy of talarozole at the two examined dosages is a possible advantage over topical retinoids.     

微小RNA主导的免疫调节在银屑病发病机制中的研究现状

银屑病是一种慢性皮肤炎症性疾病,以炎症反应、角质形成细胞增殖加速和表皮更替频繁为主要病理特点,其发病机制复杂,由固有免疫、适应性免疫及其相关免疫细胞和细胞因子参与的免疫调节在其中发挥重要作用.微小RNA参与多种生物学过程,包括细胞增殖、分化、凋亡及器官形成和发育等,与机体免疫调节密切相关.微小RNA可能通过对T细胞、角质形成细胞、固有免疫细胞以及细胞因子的调控参与到银屑病发病.     

Aryl Hydrocarbon Receptor and Autophagy-Related Protein Microtubule-Associated Protein Light Chain 3 Expression in Psoriasis

BackgroundThe aryl hydrocarbon receptor (AHR) and autophagy are both important to maintain skin homeostasis. However, they are also involved in skin disorders. So far, their roles in psoriasis pathogenesis are unknown.ObjectiveWe studied the immunohistochemical and gene expression of AHR, CYP1A1, and microtubule-associated protein light chain 3 (LC3) in lesional skin of psoriasis patients to determine correlations among them.MethodsWe included 24 psoriasis patients and ten healthy volunteers. Skin biopsies were collected. AHR, CYP1A1, and LC3 protein expression was examined by immunohistochemistry, immunofluorescence, and western blotting. AHR, CYP1A1, LC3, ATG5, BECN1 and Nrf2 mRNA levels were measured by quantitative polymerase chain reaction.ResultsAHR and CYP1A1 protein expression were higher in psoriasis lesional skin than in normal skin. LC3 protein expression was lower in psoriasis lesions than in normal controls. AHR and CYP1A1 protein expression in psoriasis lesions showed significant positive correlations with mean epidermal thickness and inflammatory cell density. Significant negative correlations were noted between LC3 protein expression in psoriasis lesions and the mean epidermal thickness or inflammatory cell density. A significant negative correlation was found between AHR and LC3 expression in psoriatic skin. AHR, CYP1A1 and Nrf2 mRNA expression were upregulated while LC3, ATG5, and BECN1 mRNA were down-regulated, in psoriatic lesional skin compared with normal controls.ConclusionAHR and autophagy could play a role in psoriasis pathogenesis by modifying epidermal hyperproliferation and inflammation. AHR and autophagy regulation are potential therapeutic targets in chronic inflammatory skin diseases.     

Expression of cellular retinoid-binding proteins during normal and abnormal epidermal differentiation.

Retinoids have important roles in growth and differentiation of epidermal cells. We have analyzed the expression of two intracellular retinoid-binding proteins, the cellular retinol-binding protein type I and the cellular retinoic acid-binding protein type I, during normal and abnormal epidermal differentiation. Both proteins were found to be expressed in normal epidermis with increasing expression from basal layer towards superficial layers. In psoriatic lesions, a hyperproliferative condition of the skin, the epidermal expression of cellular retinol-binding protein I was induced, whereas expression of cellular retinoic acid-binding protein I was sharply down-regulated. This and other features of psoriatic lesions indicate that down-regulation of cellular retinoic acid-binding protein I expression might cause aberrant retinoid-regulated gene expression in skin. In basal and squamous cell carcinomas, cellular retinoic acid-binding protein I expression was down-regulated, whereas cellular retinol-binding protein I was expressed. Apart from epidermal cells, a mesenchymal, dendritic cell-type, strongly expressing cellular retinoic acid-binding protein I, was identified in the dermis. In several hyperproliferative conditions of the skin, including psoriasis, and squamous and basal cell carcinomas, this cell type was abundant. These results have implications for the role of retinoids in normal and abnormal epidermal differentiation and suggest that part of the phenotype of psoriasis is due to inappropriate metabolism of retinoic acid in skin.     

Knockdown of lecithin retinol acyltransferase increases all‐trans retinoic acid levels and restores retinoid sensitivity in malignant melanoma cells

Retinoids such as all‐trans retinoic acid (ATRA) influence cell growth, differentiation and apoptosis and may play decisive roles in tumor development and progression. An essential retinoid‐metabolizing enzyme known as lecithin retinol acyltransferase (LRAT) is expressed in melanoma cells but not in melanocytes catalysing the esterification of all‐trans retinol (ATRol). In this study, we show that a stable LRAT knockdown (KD) in the human melanoma cell line SkMel23 leads to significantly increased levels of the substrate ATRol and biologically active ATRA. LRAT KD restored cellular sensitivity to retinoids analysed in cell culture assays and melanoma 3D skin models. Furthermore, ATRA‐induced gene regulatory mechanisms drive depletion of added ATRol in LRAT KD cells. PCR analysis revealed a significant upregulation of retinoid‐regulated genes such as CYP26A1 and STRA6 in LRAT KD cells, suggesting their possible involvement in mediating retinoid resistance in melanoma cells. In conclusion, LRAT seems to be important for melanoma progression. We propose that reduction in ATRol levels in melanoma cells by LRAT leads to a disturbance in cellular retinoid level. Balanced LRAT expression and activity may provide protection against melanoma development and progression. Pharmacological inhibition of LRAT activity could be a promising strategy for overcoming retinoid insensitivity in human melanoma cells.     

Regulation of cutaneous drug-metabolizing enzymes and cytoprotective gene expression by topical drugs in human skin in vivo

Background Individuality in the expression and regulation of hepatic drug‐metabolizing enzymes (DMEs) and cytoprotective (CP) genes is an important determinant of treatment response. There is increasing evidence that many DMEs and CP genes are also expressed in human skin. Responses to topical drugs used to treat common skin diseases, such as psoriasis, are unpredictable and may potentially be rationalized, at least in part, by interindividual differences in cutaneous DME and CP gene expression. Objectives We investigated whether three topical drugs [coal tar, all‐trans retinoic acid (atRA) and clobetasol 17‐propionate] used in routine clinical practice modulated the expression of a variety of DME and CP genes [cytochrome P450s, glutathione S‐transferases (GSTs) and drug transporters] in healthy human skin in vivo. Methods Healthy adult volunteers (n = 30) were invited to participate in the study. Each subject was randomly allocated to receive two of the three study chemicals and one control site application. Crude coal tar (n = 13), atRA (n = 14) or clobetasol 17‐propionate (n = 10) was applied under occlusion to photoprotected buttock skin for 96 h. A vehicle control (white soft paraffin) was also applied under the same conditions at an adjacent site in all subjects. Full‐thickness punch biopsies (4‐mm diameter) were then taken from treated and control sites. Total RNA was extracted and reverse transcribed into cDNA, which was used as a template in subsequent real‐time polymerase chain reaction analysis, where fluorescent output was directly proportional to input cDNA concentration. Triplicate measurements of skin mRNA expression were made from each sample, and the arithmetic mean values taken. After logarithmic transformation, the paired t‐test was used to compare values between treated and control skin. Results Cytochrome P450s CYP1A1, CYP1A2, CYP1B1, CYP2C18, quinone reductase (NQO‐1), GSTP1, γ‐glutamyl cysteine synthetase (γ‐GCS), glutathione peroxidase‐1 (GPx‐1), cyclooxygenase‐2 (COX‐2) and haem oxygenase‐1 (HO‐1) were induced by coal tar; CYP26, NADPH P450 reductase (CPR), GSTP1 and HO‐1 by atRA; and CYP3A5 by clobetasol 17‐propionate. In contrast, CYP1A1 and CYP1A2 expression was suppressed by atRA, and γ‐GCS and MRP1 by clobetasol 17‐propionate. Marked interindividual variation in gene regulation by topical drugs was seen for the majority of genes examined. Conclusions These data demonstrate that topical drugs can modulate DME gene expression in human skin in vivo and indicate that variation in the expression and regulation of these genes may be a determinant of individuality in response to topical therapies for common skin diseases.     

Treatment of psoriasis using vitamin A, vitamin A acid and oral retinoids]

Vitamin A, Vitamin A acid (retinoic acid) and their synthetic derivatives were variously applied in the management of psoriasis with different therapeutic results. Obviously, they influence the proliferation rate and the differentiation of human keratinizing epithelia and have beneficial effects on skin diseases with disturbances of keratinization, including psoriasis. Systemic application of Vitamin A has been yet largely abandonned since high dosages leading to clearing develop evident systemic toxicity. The anti-psoriatic effect of Vitamin A acid is either moderate or restricted, because of side effects. Only its combined local application with topical corticosteroids may be considered. Oral application of newly synthesized retinoids, however, was beneficial in psoriasis, particularly in erythrodermic or pustular types. With this group of retinoids new pathways were opened in dermatotherapy which may help to replace cytostatic drugs in these cases. Additionally, oral retinoid treatment may be introduced as an adjuvans in the management of widespread psoriasis, in order to enhance the effect of anthralin, PUVA or UVB treatments.