Effect of smoking on skin elastic fibres: morphometric and immunohistochemical analysis

BACKGROUND: It has been established during recent years that smoking is an independent risk factor for the development of premature facial wrinkling. The underlying mechanism is not well known, but elastic fibres of the dermis seem to be the major target of smoke components. OBJECTIVES: To determine quantitative and qualitative changes of the dermal elastic tissue of non-sun-exposed skin induced by smoking, as well as the possible mechanisms responsible for them. METHODS: Sixty-nine patients were recruited (20 nonsmokers, 19 former smokers and 30 smokers). Using static morphometry and immunohistochemistry and lectin staining we analysed elastic fibres of the dermis and their major components, elastin and microfibrillar component. RESULTS: Significantly higher values for the number of elastic fibres mm(-2) and the percentage of the area filled by them in the reticular dermis were found in smokers. Cumulative tobacco dose showed statistically significant correlations with both morphological parameters (Spearman's rank correlation coefficient). Immunohistochemistry demonstrated that the two main components of elastic fibres were altered in smokers. Plasma protease inhibitors and lectin staining were negative in all the samples. CONCLUSIONS: Smoking is an independent risk factor for the increase of elastic fibres in the reticular dermis of nonexposed skin, and it acts on their two main structural components, elastin and microfibrillar component. This increase in the area of elastic fibres in smokers is not due to newly synthesized elastic material, but to their degradation, as occurs in solar elastosis and which acts in an additive manner.     

Annular elastolytic giant cell granuloma causes an irreversible disappearance of the elastic fibres

A 67-year-old man presented with grouped red papules with a smooth surface coalescing to relatively well-demarcated plaques on his left thigh, in the axillae and on the lateral parts of the trunk. The plaques were growing slowly, and the older ones had a frilled surface. A skin biopsy showed a zone of disappearance of the elastic fibres with a rim of giant multinuclear cells with fragments of the elastic fibres in their cytoplasm. This finding is typical of annular elastolytic giant cell granuloma (AEGCG). After corticosteroid therapy, the inflammation resolved, causing the frilled surface of the lesions due to the disappearance of the elastic fibres. Remission of the skin lesions lasted for 1.5 years. A second skin biopsy taken from the site of the previous lesion showed the absence of the elastic fibres, thus their phagocytosis was irreversible.     

Relationships between lung function, smoking and morphology of dermal elastic fibres

OBJECTIVE: To investigate the relationship between lung function and dermal elastic fibres in non-smokers and smokers with and without chronic obstructive pulmonary disease (COPD). METHOD: A cross-sectional study was performed with lung function as the outcome [forced expiratory volume in the first second (FEV1)%, FEV1/forced vital capacity (FVC)% and residual volume (RV)/total lung capacity (TLC)%] and smoking (pack-years) and morphology of dermal elastic fibres (fibres/mm(2) and percentage histologic field filled with them) as independent variables, with assessment of the associations between these variables by univariate and multivariate testing. RESULTS: Sixty outpatients reporting chronic cough and/or phle\gm were enrolled (16 non-smokers/44 smokers; COPD: 26, 43.3%). Both lung function and elastic fibres in the reticular dermis (fibres/mm(2)r(s) = 0.36, percentage of the histologic field filled by elastic fibres r(s) = 0.48, P < or = 0.01) correlated with cumulative smoking (Spearman's rank correlation coefficient). Lung function parameters correlated with percentage of the histologic field filled by elastic fibres (FEV1%: r = -0.43; FEV1/FVC%: r = -0.36 and RV/TLC%: r = 0.43; P < or = 0.01, Pearson correlation coefficient), and COPD was significantly related to this morphologic parameter (odds ratio 1.26, 95% confidence interval 1.06-1.48; P = 0.006), associations that depended mainly on cumulative smoking. CONCLUSION: Lung function impairment with an obstructive pattern is associated with morphologic abnormalities in the reticular dermis appearing in the histologic section as an increase in the percentage of the field filled by elastic fibres. This relationship depends on cumulative smoking and suggests a common effect of smoking on the elastic fibres in both lung and skin.     

Elastic fibre arrangement in the skin of the pig

Summary After the removal of collagen and ground substance by autoclaving tissue samples and subsequently applying the SEM technique, a dense meshwork of elastic fibres could be demonstrated in the dermis of the pig (wild boar, domestic pig, miniature pig).The abdominal body region showed relatively large amounts of elastic fibres compared to the back and the lateral body wall. In comparison with the papillary layer and the mid-dermis, thicker elastic fibres predominated in the deeper dermis; thinner fibres were attaching to the epidermis and the pilosebaceous units. The results are discussed in relation to corresponding investigations on the human dermis.     

Morphometric analysis of elastic skin fibres from patients with: cutis laxa, anetoderma, pseudoxanthoma elasticum, and Buschke–Ollendorff and Williams–Beuren syndromes

Computed morphometric analysis of elastic skin fibres in patients with cutis laxa, anetoderma, Williams-Beuren syndrome, pseudoxanthoma elasticum (PXE), and Buschke-Ollendorff syndrome, all clinically ascertained, was performed and compared with data obtained from healthy individuals of the same age. The diameters, area fractions (AA%) and volume fractions (VV%) occupied by pre-elastic fibres and dermal elastic fibres were determined. Irrespective of age the diameter of dermal elastic fibres followed a Gaussian distribution for all groups studied. These diameters were taken into consideration for VV% determinations. Compared with data from skin of healthy subjects of similar age range, VV% of pre-elastic fibres was significantly decreased in patients with cutis laxa, anetoderma, Williams-Beuren syndrome, and PXE and undetectable in Buschke-Ollendorff patients. VV% of dermal elastic fibres was four- to fivefold increased in Buschke-Ollendorff syndrome, two- to threefold increased in PXE skin, four- to fivefold decreased in cutis laxa and anetoderma skin and about twofold decreased in Williams-Beuren skin. The diameter of oxytalan fibres was decreased in anetoderma and Williams-Beuren syndrome while oxytalan fibre diameter was unchanged in PXE and cutis laxa. The diameter of dermal elastic fibres was increased in PXE and Buschke-Ollendorff syndrome, but was decreased in anetoderma and Williams-Beuren syndrome and unchanged in cutis laxa. We demonstrated that cutis laxa, anetoderma, Williams-Beuren syndrome, PXE, and Buschke-Ollendorff syndrome could be easily differentiated by morphometric analysis of elastic skin fibres. Thus we propose that morphometric analyses together with skin biopsies are a valuable tool for distinguishing between inherited and/or acquired skin diseases known to display alterations of elastic fibres.     

Intra‐epidermal nerve fibres in human skin: back to the roots

Regarding the existence and the role of intra‐epidermal nerve fibres, the literature is ambiguous. However, performing a literature search, a landmark paper turned up that even many dermatologists seem to have forgotten, or may not even know at all. This paper is entitled ‘The innervation of human epidermis’ written by Arthur and Shelley (J Invest Dermatol, 32, 1959, 397). The full text is available via http://www.nature.com/jid/journal/v32/n3/pdf/jid195969a.pdf . The authors present data on intra‐epidermal nerves at 16 representative body areas. The existence of intra‐epidermal nerve fibres is undisputable and does not only explain clinical symptoms but may even provide a promising target for drug development.     

Transepithelial elimination of elastic fibres in the regenerated human epidermis

The elimination of elastic fibres through the regenerated epidermis of human skin was studied using histochemical, immunofluorescent and electron microscopic techniques. No abnormality was detected in the elastic fibres which were being eliminated, but they were in direct contact with the cytomembranes of some lymphocytes and were captured by histiocytes. It seemed that these elastic fibres were recognized as a foreign substance and provoked inflammation. Lymphocytes and histiocytes may play an important role in the transepithelial elimination of elastic fibres.     

新型弹力加压敷料较传统材料对体表创伤包扎效果研究

目的对比分析应用新型弹力加压敷料与传统材料包扎体表创伤的临床疗效。方法利用大、中、小三种型号的弹力加压敷料,用以包扎全身各部位体表伤口。同时与普通棉垫、绷带相对照,比较急救医护人员包扎操作所用的时间以及伤口包扎止血的效果。结果弹力加压敷料可完成普通棉垫、绷带所有的包扎任务,急救医护人员操作的时间明显短于使用普通棉垫、绷带,P〈0．05,伤口的止血效果与普通棉垫、绷带差异无统计学意义,P〉0．05。结论此弹力加压敷料可有效地、快速地、牢固地对全身各部位体表伤口进行包扎,易于操作,可在院外急救中发挥良好的包扎作用。     

弹力纤维染色在营养不良型大疱性表皮松解症中的诊断价值

 目的:通过免疫组织化学染色回顾性诊断营养不良型大疱性表皮松解症（DEB）患者，并了解弹力纤维在DEB和大疱性类天疱疮(BP)患者皮损中的分布情况，进一步探讨弹力纤维染色在DEB诊断中的临床意义。方法： 收集17例DEB和3例BP患者皮损标本和临床资料,采用免疫组织化学染色方法检测角蛋白14、层粘蛋白5和胶原蛋白Ⅳ、Ⅶ在DEB患者中的表达，弹力纤维染色检测弹力纤维在DEB患者和BP患者皮损中的分布情况。结果：17例DEB患者皮损中，角蛋白14和层粘蛋白5在真、表皮裂隙的表皮侧表达，胶原蛋白Ⅳ在表皮侧表达或表达缺失，而胶原蛋白Ⅶ表达缺失。弹力纤维在17例DEB患者真皮浅中层均缺失，而在BP患者真皮乳头处减少。结论：DEB可根据角蛋白14、层粘蛋白5、胶原蛋白Ⅳ和胶原蛋白Ⅶ在皮损中的免疫组化检测结果诊断。弹力纤维在DEB和BP患者皮肤中分布不同，弹力纤维染色可作为DEB和BP的鉴别诊断依据之一。     

Rubbing test responses of the skin to man-made mineral fibres of different diameters

The irritant potency of 5 types of insulation wools (2 types of rockwool and 3 types of glass wool) were studied on the basis of their differences in diameter by a standardized rubbing test. Assessment was done by laser Doppler flowmetry (LDF) and erythema scores. Insulation wools show a wide distribution of the diameter around the mean. Of the rockwool material, 30% consisted of small grains, called "shot". The control test site did not change over time; thus, the rubbing procedure itself does not seem to contribute to the skin reactions. All fibre types proved to be irritant to the skin. The irritant reactions did not correspond with the mean diameter, although the fibre type with the smallest diameter was the least irritant and the fibre type with the largest diameter the strongest. The presence of "shot" had a significant effect on the LDF responses. "Shot" and the distribution around the mean diameter may play a role in eliciting the skin irritation by insulation wools.     

Immunohistochemical study of epidermal nerve fibres in involved and uninvolved psoriatic skin using confocal laser scanning microscopy

Abstract Psoriasis is a typical hyperproliferative epidermal disease whose aetiopathogenesis is still to be defined. One of the most likely hypotheses is that it has a neurogenic origin correlated with an altered release of some neuropeptides by sensitive cutaneous nerves via antidromic pathways. As there are conflicting reports about the existence of cutaneous nerve alterations in psoriasis, we carried out an immunolocalization study using the protein gene product 9.5 as a marker for neuronal structures observed by confocal laser scanning microscopy in order to determine the pattern of sensory nerves in psoriatic skin. The investigation was carried out on cutaneous biopsies taken from involved (mature and long-established lesions) and uninvolved skin of ten patients with extensive chronic plaque psoriasis. In uninvolved psoriatic skin a significant decrease in epidermal nerve fibres was found, a further decrease was observed in mature lesions and almost a complete lack of epidermal nerve fibres in long-established psoriatic lesions. The reduction in epidermal nerve fibres and the consequent loss of relationship between these nerve structures and the skin immunocompetent cells (antigen-presenting cells, Langerhans cells, keratinocytes) might be a factor of fundamental importance in the self-maintenance of the disease. Received: 26 May 1997     

All-trans retinoic acid promotes the repair of tortuosity of elastic fibres in rat skin

To elucidate the repair effects of all-trans retinoic acid (t-RA) on ultraviolet (UV)-induced tortuosity of elastic fibres in rat skin, the hind limbs of Sprague-Dawley rats were irradiated at a suberythemal dose of UV (three times/week for 6 weeks) and 0.025% t-RA in ethanol was applied topically five times/week for 6 weeks. The three-dimensional arrangement of elastic fibres with special reference to their linearity was quantified by image analysis using a scanning electron microscope following a combination of intravascular resin injection and selective digestion using formic acid. When t-RA was topically applied for 6 weeks on wrinkles formed by 6 weeks' exposure of the skin of rat hind limbs to UV radiation, the wrinkles disappeared to control levels, concomitant with an improvement in skin elasticity. The linearity of the elastic fibres was significantly (P < 0.01) increased compared with age-matched UV-irradiated controls. These findings suggest that the degeneration and deposition of elastic fibres accompanied by an increase in their linearity is involved in the process of wrinkle repair by topical application of t-RA.     

Morphological architecture and distribution of blood capillaries and elastic fibres in the human skin

This study was undertaken to clarify the morphological features in the blood capillary and elastic fibre distribution of the human skin in terms of susceptibility to pressure sore development. Skin tissues were obtained from bony areas: the sacrum and ischial tuberosity and non-bony area: the centre of the gluteus maximus of 5 aged subjects post mortem for examination using light and scanning electron microscopy. It was observed that the sacral skin had finger-like papillae and underneath the blood capillary loops were most numerous. In the ischial skin the dermal papillae consisted of a combination of finger-like and trapezoid shapes having moderate density of blood capillaries. In contrast, the dermal papillae in the gluteal skin were almost flat, so that the blood capillaries were scattered. The size of elastic bundles in the papillary layer of the sacral, ischial and gluteal skin ranged from 2 to 3 microns, 5 to 10 microns, and 3 to 5 microns, respectively. The elastic fibres were densely distributed in the ischial skin while less so in the sacral skin.     

The utility of elastic Verhoeff‐Van Gieson staining in dermatopathology

Elastic fibers are important components of the skin and are responsible for skin elasticity. Genetic defects are well‐known in numerous hereditary elastic tissue disorders and skin biopsies are often the first step in the evaluation of those disorders. Verhoeff‐Van Gieson elastic staining is a simple method that is used for visualizing elastic fibers. With the development of modern immunohistochemical methods, the value of routine histochemical staining is sometimes underestimated. Histochemical stains are less expensive, easy to perform and help to resolve numerous diagnostic quandaries in dermatopathology. This article focuses on the value of elastic tissue staining in dermatopathology, with a focus on primary elastic tissue disorders, alopecia, inflammatory skin disorders and neoplastic proliferations.     

Increment of subcutaneous adipose tissue is associated with decrease of elastic fibres in the dermal layer

Obesity is a significant risk factor for various skin disorders, including pressure ulcer and delayed wound healing. We previously showed that increment of subcutaneous adipose tissue contributes to poor skin condition by decreasing dermal elasticity. Here, we examined the mechanism involved. Histologic observation of abdominal skin from middle‐aged females with a wide range of body mass index (BMI), an indicator of subcutaneous fat mass, showed that dermal elastic fibre abundance was significantly decreased with increment of BMI. Concomitantly, adipocytes were significantly enlarged. Adipocyte enlargement was significantly negatively correlated with dermal elastic fibre abundance. We hypothesized that enlarged adipocytes negatively influence dermal elastic fibres, so we investigated elastic fibre‐degrading factors in in vitro‐cultured enlarged adipocytes. MMP9 gene expression and secretion were significantly increased; further, these changes were blocked by extracellular signal‐regulated kinase (ERK) inhibitor. Nuclear translocation (activation) of AP‐1, a downstream ERK signalling molecule, was also observed in enlarged adipocytes. MMP9 abundance was significantly increased in skin of subjects with high BMI and enlarged adipocytes. These results suggest that increment of subcutaneous adipose tissue leads to adipocyte enlargement together with increased degradation of dermal elastic fibres, mediated at least in part by an ERK signalling‐mediated increase of MMP9 in enlarged adipocytes.     

Carbon dioxide laser treatment promotes repair of the three-dimensional network of elastic fibres in rat skin

BACKGROUND: We have previously reported that ultraviolet (UV) B irradiation induces a loss of linearity in the three-dimensional structure of dermal elastic fibres, which results in the reduction of elastic properties of the skin and leads to wrinkle formation. We further reported that repair of wrinkles by all-trans retinoic acid is accompanied by recovery of the linearity of elastic fibres. Carbon dioxide (CO2) lasers are widely used for treating wrinkles in cosmetic surgery. OBJECTIVES: To perform CO2 laser treatment of wrinkles induced in rat skin by UVB irradiation and to evaluate changes in the three-dimensional structure of dermal elastic fibres during wrinkle repair. METHODS: Wrinkles were induced in the hind limb skin of Sprague-Dawley rats by UVB irradiation (130 mJ cm-2 three times weekly for 6 weeks), followed by CO2 laser treatment (11.3 J cm-2). The surface appearance of the skin was evaluated by replica observation 6 and 10 weeks after CO2 laser treatment followed by measurement of mechanical properties using a Cutometer. Subsequently, perfusion fixation and digestion with formic acid were performed and elastic fibres were observed by scanning electron microscopy (SEM). Image analysis of SEM micrographs was carried out to evaluate the linearity in the three-dimensional structure of elastic fibres. RESULTS: Six weeks after CO2 laser treatment, all parameters of skin mechanical properties in the UVB-irradiated group recovered to levels of the control non-irradiated group, accompanied by repair of wrinkles and a significant increase in linearity of the three-dimensional structure of elastic fibres. CONCLUSIONS: These findings indicate that CO2 laser treatment has a therapeutic potential to repair wrinkles to non-irradiated levels through recovery of the three-dimensional structure of elastic fibres.     

强脉冲光照射对小鼠皮肤胶原纤维、弹性纤维及透明质酸含量的影响

目的 探讨强脉冲光照射对昆明小鼠皮肤胶原纤维、弹性纤维、透明质酸含量的意义。方法用强脉冲光照射小鼠右侧背部皮肤,左侧为对照,取各时间点照射组和对照组皮肤进行组织学观察,包括HE染色、Ⅰ型和Ⅲ型胶原纤维饱和苦味酸-天狼猩红染色、弹性纤维Gomori醛品红法染色,同时提取皮肤组织,碱水解-分光光度法测定羟脯氨酸含量,放射免疫法测定透明质酸含量。结果 照射后2周,真皮厚度较对照组增加（t = 4.623,P < 0.05）,4周时达最大值,较对照组增加18.71%,8周时仍大于对照组,差异有统计学意义（t = 3.904,P < 0.05）。照射后1周,Ⅲ型胶原纤维较对照组增加40.54%（t = 5.129,P < 0.05）,照射后2周和4周,Ⅰ型和Ⅲ型胶原纤维均较对照组增多明显,至8周时,均大于对照组（P < 0.05）。照射后2 ~ 8周,弹性纤维均较对照组增多（P < 0.05）;照射后1 ~ 8周,羟脯氨酸含量均较对照组增多（P < 0.05）。照射后1 d和3 d,透明质酸含量显著增加,1 ~ 8周,渐进性降低,但均高于对照组（P < 0.05）。结论 强脉冲光照射小鼠皮肤可刺激真皮胶原纤维、弹性纤维、透明质酸含量增加。     

Increased deposition of fibulin-2 in solar elastosis and its colocalization with elastic fibres

BACKGROUND: Fibulin-2 is a 195-kDa protein belonging to a novel family of extracellular matrix proteins that might be involved in microfibril and elastic fibre organization. OBJECTIVES: To determine the localization of fibulin-2 in relation to elastic fibres in normal skin and in solar elastosis characterized by increased elastotic material in the papillary dermis. METHODS: The expression and synthesis of fibulin-2 was investigated by means of in situ hybridization, immunohistochemistry and Western blot analysis in normal and photoaged skin. RESULTS: Immunohistochemistry and elastic tissue staining revealed that fibulin-2 deposition mainly colocalized with microfibrils and elastin fibres, with a marked staining of elastotic material in solar elastosis. Western blot analysis demonstrated that in photoaged skin fibulin-2 showed the same electrophoretic mobility as in sun-protected skin. However, in actinic elastosis the amount of fibulin-2 was significantly higher. In addition, smaller degradation products were detectable, presumably reflecting increased proteinase activity in photodamaged skin. CONCLUSIONS: This study shows that deposition of fibulin-2 and elastin is highly co-ordinated, indicating that this protein plays an important role in elastic fibre and microfibril formation in normal and actinically damaged skin.