一氧化氮和一氧化氮合酶与皮肤血管炎性疾病

一氧化氮是体内重要的信号转导分子,具有广泛的生物学效应。一氧化氮合酶的表达受免疫分子的调控。最近研究发现,一氧化氮和一氧化氮合酶表达异常与皮肤血管炎性疾病的发病关系密切。现就一氧化氮和一氧化氮合酶及其与皮肤血管炎性疾病的关系的研究现状进行综述。     

一氧化氮和一氧化氮合酶与皮肤血管炎性疾病

一氧化氮是体内重要的信号转导分子，具有广泛的生物学效应。一氧化氮合酶的表达受免疫分子的调控。最近研究发现，一氧化氮和一氧化氮合酶表达异常与皮肤血管炎性疾病的发病关系密切。现就一氧化氮和一氧化氮合酶及其与皮肤血管炎性疾病的关系的研究现状进行综述。     

过氧化物酶体增殖激活物受体γ在皮肤自然衰老过程中的表达及意义

目的研究过氧化物酶体增殖激活物受体γ（PPARγ）在皮肤自然衰老过程中的表达及其意义。方法采用免疫组化方法（SP法）检测PPARγ的蛋白表达水平，RT—PCR方法检测PPARγ的mRNA表达水平。结果免疫组化研究结果表明中老年组PPARγ蛋白的表达强度显著高于青少年组（x^2=15．48，P=0．001）；RT—PCR检测结果表明中老年组PPARγmRNA的平均表达水平为0．697±0．204，青少年组为0．337±0．124，中老年组亦显著高于青少年组（t=8．25，P〈0．001）。结论随着年龄的增加，皮肤PPARγ的表达增高，在皮肤自然老化过程中可能起重要作用，PPARγ有可能成为研制延缓皮肤自然衰老药物的新靶点。     

iNOS在皮肤肿瘤中的表达及其意义

目的:检测诱导型一氧化氮合酶(iNOS)在皮肤良恶性肿瘤中的表达。方法:采用免疫组织化学技术检测25例脂溢性角化病、25例光线性角化病、25例基底细胞癌、30例鳞状细胞癌(I级13例,II-III级17例)、10例正常皮肤组织中iNOS的表达。结果:2例(8.00%)脂溢性角化病、13例(52.00%)光线性角化病、11例(44.00%)基底细胞癌、22例(73.33%)鳞状细胞癌中iNOS呈阳性表达,正常皮肤表达均为阴性。iNOS在鳞状细胞癌、基底细胞癌及光线性角化病中的阳性率明显高于脂溢性角化病组(P<0.01),鳞状细胞癌组与光线性角化病组间无明显差别(P>0.05),与其他各组间差异显著(P<0.01或P<0.05),II III级鳞状细胞癌iNOS表达明显高于I级鳞状细胞癌(P<0.05)。结论:皮肤肿瘤中存在iNOS的表达,其合成的一氧化氮可能在皮肤的癌前病变及恶性肿瘤的发生、发展中起到一定的作用。其表达可能有助于皮肤肿瘤恶性度及预后的判断。     

皮肤恶性黑素瘤中诱导型一氧化氮合酶mRNA及其蛋白的表达

目的探讨皮肤恶性黑素瘤中诱导型一氧化氮合酶（iNOS）的表达及其临床意义。方法免疫组化方法检测30例皮肤恶性黑素瘤患者肿瘤组织中iNOS蛋白的表达，逆转录聚合酶链反应（RT-PCR）检测其中6例患者肿瘤组织和肿瘤邻近正常组织中iNOSmRNA的表达。结果iNOS在肿瘤组织中无论蛋白或mRNA阳性表达率皆明显高于邻近正常组织（P〈0．05）。其中iNOS蛋白在无转移的恶性黑素瘤中阳性表达率为69．2％，有转移的恶性黑素瘤中阳性表达率为100％。结论iNOS表达异常在恶性黑素瘤发生、发展与转移过程中可能起重要作用。     

一氧化氮及一氧化氮合酶与皮肤血管炎的关系

本研究旨在探讨一氧化氮(NO)/一氧化氮合酶(NOS)与皮肤血管炎的关系,并为皮肤血管炎的诊断和病情评价提供依据.     

黄芩甙影响人成纤维细胞诱导型一氧化氮合酶蛋白表达研究

目的 研究成纤维细胞诱导型一氧化氮合酶(iNOS)蛋白表达情况，以及细胞因子和黄芩甙对其表达的影响，探讨黄芩甙治疗银屑病机制。方法 体外培养的成纤维细胞，通过TNF-α、IFN-γ和IL-8刺激，用免疫组化方法研究成纤维细胞表达iNOS情况，并观察黄芩甙对其表达的影响。结果 未受到细胞因子刺激时成纤维细胞不表达iNOS；TNF-α(终浓度1000U／mL)、IFN-γ(200U／mL)、IL-8(200pg/mL)单独或分别组合后刺激成纤维细胞24h后的蛋白分析显示：单独TNF-α能够刺激成纤维细胞表达较弱iNOS，而IFN-γ或IL-8处理未显示该效应，联合TNF-α、IFN-γ和IL-8显示增强的诱导iNOS表达作用，免疫组化有强染色区，位于胞浆近胞核处；50μg／mL黄芩甙能够抑制细胞因子诱导成纤维细胞表达iNOS。结论黄芩甙能够抑制细胞因子刺激成纤维细胞的iNOS蛋白表达，减少NO的产生，发挥抗炎和治疗银屑病的作用。     

非酶糖化与皮肤自然衰老的关系

皮肤自然衰老的机制尚不完全清楚。非酶糖化尤其是它的晚期糖化终末产物（advancedgly—cationendproducts,AGEs）在其中起重要作用。研究发现,AGEs在皮肤的不断累积导致真皮胶原蛋白发生交联,皮肤弹性下降;并参与了促进成纤维细胞凋亡的过程;发现细胞内的波形蛋白是AGEs修饰的靶点;细胞外基质因为AGEs的累积也发生改变,包括透明质酸的下降,以及基质金属蛋白酶系统失衡。此外,最近研究发现表皮也有AGEs的累积。     

皮肤自然衰老的分子生物学机制

衰老是指机体对环境的适应随年龄增长进行性下降。皮肤衰老表现为形态和功能等方面改变。在细胞,分子水平,可表现为染色体端粒缩短,ＤＮＡ甲基化水平下降,表皮生长因子等生长因子及其受体或其它生长,抑制相关基因（如成视网膜细胞瘤基因,ｆｏｓ,ｊｕｎ,ＧＡＤＤ１５３）数量,功能的变化,对外界反应性逐渐降低,进而皮肤细胞增殖分析能力减弱,皮肤呈出出衰老外貌。     

一氧化氮与皮肤

一氧化氮作为一种多效性生物调节分广日益受到人们的重视,它可在机体多种细胞中合成,并在多种生理和病理过程中起到重要作用。近年研究表明,皮肤组织中一些细胞亦能原生和被诱导合成一氧化氮,一氧化氮在皮肤生理和病理过程中的具体作用尚不明,但已有证据表明,它可能参与皮肤血液循环、抗感染、组织修复、免疫和炎症反应等诸多方面的调节,并可能与某些皮肤病的发生发展有密切联系。     

Skin wound healing in the SKH-1 female mouse following inducible nitric oxide synthase inhibition

BACKGROUND: The inducible isoform of the nitric oxide (NO) synthase (NOS) enzyme (iNOS) is upregulated by inflammatory mediators and/or other pathological stresses, generating high, sustained levels of NO. Cumulative data suggest a role for NO in the regulation of skin wound healing, although it is not clear to what extent NO generated by iNOS, and possibly endothelial NOS (eNOS), contribute to that healing process. Because of the current lack of understanding regarding the contribution of iNOS in wound healing, as well as the lack of wound healing data available for SC-842, an iNOS inhibitor, this in vivo study was conducted to investigate the possible role of SC-842 in interfering with wound healing. OBJECTIVES: This study evaluated whether inhibition of iNOS affects incisional skin wound healing. METHODS: Using a cutaneous full-thickness, sutured, incisional wound model in hairless SKH-1 mice, the role of iNOS in the wound healing process was evaluated by comparing in vivo effects of the iNOS inhibitor, SC-842, at various doses that result in selective inhibition of iNOS as well as nonselective NOS inhibition (as evidenced by elevated blood pressure resulting in inhibition of eNOS and/or neuronal NOS). Dexamethasone was used as a positive control. RESULTS: There were no differences in wound healing at day 28 postwounding, as evaluated by tensile strength and histology, between SC-842- and vehicle-treated animals. A decrease in tensile strength was noted at day 14 postwounding in wounds from the mid- and high-dose-treated animals as compared with vehicle-treated animals, but this difference was slight and was not associated with histological differences from vehicle-treated controls. CONCLUSIONS: These data indicate that iNOS inhibition does not adversely affect the healing of incisional wounds in SKH-1 mice as assessed over 28 days by wound tensile strength and histology.     

痤疮丙酸杆菌诱导人单核细胞iNOS、NO及 Nramp1表达的研究

目的：观察人源性单核细胞系THP-1在痤疮丙酸杆菌（P．acnes）活菌刺激后，不同时段诱导型一氧化氮合成酶（iNOS）、自然抗性相关巨噬细胞蛋白1（Nramp1）的表达水平和细胞培养液上清中一氧化氮（NO）的含量，初步探讨天然免疫过程中单核-巨噬细胞反应氮中间产物（RNI）系统对PP．acnes感染的反应机制。方法：使用实时荧光定量PCR技术检测iNOS、Nramp1表达量，Griess法检测培养液上清NO含量。结果：P．acnes活菌可以有效诱导人源性单核细胞系THP-1 iNOS、NO和Nramp1的显著表达，表达量在刺激后6～24h达到高峰。结论：天然免疫中的RNI系统在P．acnes感染的初期即参加免疫反应，同时Nramp1也开始表达，对RNI系统起到辅助作用。     

Expression of the inducible isoform of nitric oxide synthase in pigment cell lesions of the skin

Nitric oxide (NO) is a small molecule produced during the conversion of L-arginine to L-citrulline by NO synthase (NOS). Several isoforms of NOS exist, of which the Ca2+-independent, inducible NOS (iNOS or NOS2) is most prominently expressed by macrophages. iNOS activity and increased levels of iNOS have been found in various tumours and tumour cell lines but not in normal tissues; however, the precise role of NO in tumour progression has yet to be elucidated. We studied the expression of iNOS in paraffin sections of 41 benign naevi and 52 primary malignant melanomas (MM) of the skin, as well as in 13 metastatic MM. In addition, nitrotyrosine, indicative of NO production and formation of peroxynitrite, was studied in frozen sections of 13 naevi and 30 MM. Virtually all naevi expressed iNOS, but very few expressed nitrotyrosine, indicating either that iNOS in naevi is functionally inactive, or that naevus cells lack reactive oxygen radicals and thus do not form peroxynitrite. Normal melanocytes in adjacent uninvolved skin were unreactive for both markers. In MM, iNOS was most frequently expressed in the 'pure' and 'invasive' radial growth phase (RGP), whereas expression in the vertical growth phase (VGP) and metastatic phase occurred only in 76% of cases; moreover, in these latest phases of tumour progression, iNOS staining was weak and focal. We conclude that iNOS is expressed de novo in most benign pigment cell lesions. In MM (iNOS-generated) NO appears to play an important part in the early steps of invasion (i.e. the 'invasive' RGP), where it may stimulate neo-angiogenesis and may be a prerequisite for further tumour progression; this view is also supported by the finding of iNOS in the associated blood vessels in the papillary dermis. Finally, our data suggest that (iNOS-generated) NO plays a less significant part in the VGP and in metastatic melanoma.     

Protective role of nitric oxide-mediated inflammatory response against lipid peroxidation in ultraviolet B-irradiated skin

Ultraviolet (UV) irradiation is known to induce serious oxidative damage in the skin via lipid peroxidation. Nitric oxide (NO) synthesized by keratinocytes, melanocytes and endothelial cells in response to proinflammatory cytokines and UV radiation, has been reported to prevent UV-induced apoptosis in the skin. We have examined the effects of NO on UVB-induced lipid peroxidation in murine skin in vivo. UVB induced a dose-dependent increase in lipid peroxidation of skin extracts in vitro; however, lipid peroxidation in the skin in vivo remained unaffected at irradiation doses of less than 1.0 J cm-2 and decreased significantly at doses over 1.5 J cm-2 (P < 0.01). Time-delayed inhibition of lipid peroxidation in the skin in vivo was observed after irradiation at 1.5 J cm-2. Administration of N G-nitro-L-arginine methyl ester (L-NAME), an inhibitor of NO synthesis, enhanced lipid peroxidation (P < 0.05), while it suppressed the ear-swelling response (ESR), a biological marker of inflammation. By contrast, administration of sodium nitroprusside, an NO enhancer, suppressed lipid peroxidation (P < 0. 01), while it enhanced the ESR. Expression of inducible nitric oxide synthase (iNOS) was observed from 12 to 48 h postirradiation at doses of 0.4-1.6 J cm-2. The UVB-induced iNOS expression was markedly inhibited by L-NAME, suggesting that iNOS is a major enzyme in the production of NO. These results suggest that NO acts as a mediator of the inflammatory response in UVB-irradiated skin, and that lipid peroxidation is inversely regulated with the NO-mediated inflammatory response in vivo.     

金属硫蛋白I、II在正常人皮肤中的表达及其意义

目的:探讨金属硫蛋白II、I(Metallothionein II、I,MT-I、II)在正常人皮肤的表达及其意义。方法:采用组织芯片、免疫组化灰度分析方法,研究正常皮肤MT-II、I表达情况。结果:(1)正常皮肤MT-II、I主要表达于表皮基底层和基底层上1~2层角质形成细胞。真皮极少数成纤维细胞、外毛根鞘、小汗腺导管上皮细胞以及皮脂腺外单层嗜碱性细胞也有MT表达。(2)同性别同部位正常皮肤MT-II、I表达强度与年龄呈显著负相关(面r=-0.73,臀部r=-0.98,P<0.01),40岁之前面部皮肤表达强度随年龄增长而快速下降。(3)同年龄同部位正常皮肤MT-II、I表达强度男性显著高于女性(t=6.95,P<0.01)。(4)同年龄同性别正常皮肤MT-II、I表达强度遮光部位显著高于曝光部位(t=4.14,P<0.01)。结论:正常皮肤MT-II、I的表达可能存在人种、性别和年龄差异。老化皮肤合成MT的能力降低,MT-II、I在对抗皮肤老化方面可能有重要作用。皮肤光老化与MT-II、I表达降低有关。     

金属硫蛋白Ⅰ、Ⅱ在正常人皮肤中的表达及其意义

目的：探讨金属硫蛋白Ⅰ、Ⅱ（Metallothionein Ⅰ、Ⅱ，MT—Ⅰ、Ⅱ）在正常人皮肤的表达及其意义。方法：采用组织芯片、免疫组化灰度分析方法，研究正常皮肤MT—Ⅰ、Ⅱ表达情况。结果：（1）正常皮肤MT—Ⅰ、Ⅱ主要表达于表皮基底层和基底层上1-2层角质形成细胞。真皮极少数成纤维细胞、外毛根鞘、小汗腺导管上皮细胞以及皮脂腺外单层嗜碱性细胞也有MT表达。（2）同性别同部位正常皮肤MT—Ⅰ、Ⅱ表达强度与年龄呈显著负相关（面r=-0．73，臀部r=-0．98，P〈0．01），40岁之前面部皮肤表达强度随年龄增长而快速下降。（3）同年龄同部位正常皮肤MT—Ⅰ、Ⅱ表达强度男性显著高于女性（t=6．95，P〈0．01）。（4）同年龄同性别正常皮肤MT—Ⅰ、Ⅱ表达强度遮光部位显著高于曝光部位（t=4．14，P〈0．01）。结论：正常皮肤MT—Ⅰ、Ⅱ的表达可能存在人种、性别和年龄差异。老化皮肤合成MT的能力降低，MT—Ⅰ、Ⅱ在对抗皮肤老化方面可能有重要作用。皮肤光老化与MT—Ⅰ、Ⅱ表达降低有关。