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Sample records for aged human skin

  1. [Experimental models of human skin aging].

    PubMed

    Nikolakis, G; Zoschke, C; Makrantonaki, E; Hausmann, C; Schäfer-Korting, M; Zouboulis, C C

    2016-02-01

    The skin is a representative model for the study of human aging. Despite the high regenerative capacity of the skin, skin physiology changes over the course of life. Medical and cosmetic research is trying to prevent aging, to slow, to stop, or to reverse it. Effects of age-related DNA damage and of changing skin structure on pharmacological parameters are largely unknown. This review article summarizes the state of scientific knowledge in the field of experimental models of human skin aging and shows approaches to improve organotypic skin models, to develop predictive models of aging, and improve aging research.

  2. [Physiological features of skin ageing in human].

    PubMed

    Tikhonova, I V; Tankanag, A V; Chemeris, N K

    2013-01-01

    The issue deals with the actual problem of gerontology, notably physiological features of human skin ageing. In the present review the authors have considered the kinds of ageing, central factors, affected on the ageing process (ultraviolet radiation and oxidation stress), as well as the research guidelines of the ageing changes in the skin structure and fuctions: study of mechanical properties, microcirculation, pH and skin thickness. The special attention has been payed to the methods of assessment of skin blood flow, and to results of investigations of age features of peripheral microhemodynamics. The laser Doppler flowmetry technique - one of the modern, noninvasive and extensively used methods for the assessmant of skin blood flow microcirculation system has been expanded in the review. The main results of the study of the ageing changes of skin blood perfusion using this method has been also presented.

  3. Oxidative Stress in Aging Human Skin

    PubMed Central

    Rinnerthaler, Mark; Bischof, Johannes; Streubel, Maria Karolin; Trost, Andrea; Richter, Klaus

    2015-01-01

    Oxidative stress in skin plays a major role in the aging process. This is true for intrinsic aging and even more for extrinsic aging. Although the results are quite different in dermis and epidermis, extrinsic aging is driven to a large extent by oxidative stress caused by UV irradiation. In this review the overall effects of oxidative stress are discussed as well as the sources of ROS including the mitochondrial ETC, peroxisomal and ER localized proteins, the Fenton reaction, and such enzymes as cyclooxygenases, lipoxygenases, xanthine oxidases, and NADPH oxidases. Furthermore, the defense mechanisms against oxidative stress ranging from enzymes like superoxide dismutases, catalases, peroxiredoxins, and GSH peroxidases to organic compounds such as L-ascorbate, α-tocopherol, beta-carotene, uric acid, CoQ10, and glutathione are described in more detail. In addition the oxidative stress induced modifications caused to proteins, lipids and DNA are discussed. Finally age-related changes of the skin are also a topic of this review. They include a disruption of the epidermal calcium gradient in old skin with an accompanying change in the composition of the cornified envelope. This modified cornified envelope also leads to an altered anti-oxidative capacity and a reduced barrier function of the epidermis. PMID:25906193

  4. Aging Skin

    MedlinePlus

    ... email address Submit Home > Healthy Aging > Wellness Healthy Aging Aging skin More information on aging skin When it ... treated early. Return to top More information on Aging skin Read more from womenshealth.gov Varicose Veins ...

  5. Skin Aging

    MedlinePlus

    Your skin changes as you age. You might notice wrinkles, age spots and dryness. Your skin also becomes thinner and loses fat, making it ... heal, too. Sunlight is a major cause of skin aging. You can protect yourself by staying out ...

  6. Role of Age-Associated Alterations of the Dermal Extracellular Matrix Microenvironment in Human Skin Aging

    PubMed Central

    Quan, Taihao; Fisher, Gary J

    2015-01-01

    Human skin is largely composed of a collagen-rich connective tissue, which provides structural and functional support. The collagen-rich connective tissue is produced, organized, and maintained by dermal fibroblasts. During aging, dermal collagen fibrils undergo progressive loss and fragmentation, leading to thin and structurally weakened skin. Age-related alterations of collagen fibrils impairs skin structure and function and creates a tissue microenvironment that promotes age-related skin diseases, such as delayed wound healing and skin cancer development. This review describes cellular mechanisms that give rise to self-perpetuating, collagen fibril fragmentation that creates an age-associated dermal microenvironment (AADM), which contributes to decline of human skin function. PMID:25660807

  7. CCN1 contributes to skin connective tissue aging by inducing age-associated secretory phenotype in human skin dermal fibroblasts.

    PubMed

    Quan, Taihao; Qin, Zhaoping; Robichaud, Patrick; Voorhees, John J; Fisher, Gary J

    2011-08-01

    Dermal connective tissue collagen is the major structural protein in skin. Fibroblasts within the dermis are largely responsible for collagen production and turnover. We have previously reported that dermal fibroblasts, in aged human skin in vivo, express elevated levels of CCN1, and that CCN1 negatively regulates collagen homeostasis by suppressing collagen synthesis and increasing collagen degradation (Quan et al. Am J Pathol 169:482-90, 2006, J Invest Dermatol 130:1697-706, 2010). In further investigations of CCN1 actions, we find that CCN1 alters collagen homeostasis by promoting expression of specific secreted proteins, which include matrix metalloproteinases and proinflammatory cytokines. We also find that CCN1-induced secretory proteins are elevated in aged human skin in vivo. We propose that CCN1 induces an "Age-Associated Secretory Phenotype", in dermal fibroblasts, which mediates collagen reduction and fragmentation in aged human skin.

  8. Attenuated noradrenergic sensitivity during local cooling in aged human skin

    PubMed Central

    Thompson, Caitlin S; Holowatz, Lacy A; Kenney, W. Larry

    2005-01-01

    Reflex-mediated cutaneous vasoconstriction (VC) is impaired in older humans; however, it is unclear whether this blunted VC also occurs during local cooling, which mediates VC through different mechanisms. We tested the hypothesis that the sensitization of cutaneous vessels to noradrenaline (NA) during direct skin cooling seen in young skin is blunted in aged skin. In 11 young (18–30 years) and 11 older (62–76 years) men and women, skin blood flow was monitored at two forearm sites with laser Doppler (LD) flowmetry while local skin temperature was cooled and clamped at 24°C. Cutaneous vascular conductance (CVC; LD flux/mean arterial pressure) was expressed as percentage change from baseline (%ΔCVCbase). At one site, five doses of NA (10−10–10−2m) were sequentially infused via intradermal microdialysis during cooling while the other 24°C site served as control (Ringer solution + cooling). At control sites, VC due to cooling alone was similar in young versus older (−54 ± 5 versus −56 ± 3%ΔCVCbase, P= 0.46). In young, NA infusions induced additional dose-dependent VC (10−8, 10−6, 10−4 and 10−2m: −70 ± 2, −72 ± 3, −78 ± 3 and −79 ± 4%ΔCVCbase; P < 0.05 versus control). In older subjects, further VC did not occur until the highest infused dose of NA (10−2m: −70 ± 5%ΔCVCbase; P < 0.05 versus control). When cutaneous arterioles are sensitized to NA by direct cooling, young skin exhibits the capacity to further constrict to NA in a dose-dependent manner. However, older skin does not display enhanced VC capacity until treated with saturating doses of NA, possibly due to age-associated decrements in Ca2+ availability or α2C-adrenoceptor function. PMID:15705648

  9. Natural and sun-induced aging of human skin.

    PubMed

    Rittié, Laure; Fisher, Gary J

    2015-01-05

    With worldwide expansion of the aging population, research on age-related pathologies is receiving growing interest. In this review, we discuss current knowledge regarding the decline of skin structure and function induced by the passage of time (chronological aging) and chronic exposure to solar UV irradiation (photoaging). Nearly every aspect of skin biology is affected by aging. The self-renewing capability of the epidermis, which provides vital barrier function, is diminished with age. Vital thermoregulation function of eccrine sweat glands is also altered with age. The dermal collagenous extracellular matrix, which comprises the bulk of skin and confers strength and resiliency, undergoes gradual fragmentation, which deleteriously impacts skin mechanical properties and dermal cell functions. Aging also affects wound repair, pigmentation, innervation, immunity, vasculature, and subcutaneous fat homeostasis. Altogether, age-related alterations of skin lead to age-related skin fragility and diseases.

  10. Natural and Sun-Induced Aging of Human Skin

    PubMed Central

    Rittié, Laure; Fisher, Gary J.

    2015-01-01

    With worldwide expansion of the aging population, research on age-related pathologies is receiving growing interest. In this review, we discuss current knowledge regarding the decline of skin structure and function induced by the passage of time (chronological aging) and chronic exposure to solar UV irradiation (photoaging). Nearly every aspect of skin biology is affected by aging. The self-renewing capability of the epidermis, which provides vital barrier function, is diminished with age. Vital thermoregulation function of eccrine sweat glands is also altered with age. The dermal collagenous extracellular matrix, which comprises the bulk of skin and confers strength and resiliency, undergoes gradual fragmentation, which deleteriously impacts skin mechanical properties and dermal cell functions. Aging also affects wound repair, pigmentation, innervation, immunity, vasculature, and subcutaneous fat homeostasis. Altogether, age-related alterations of skin lead to age-related skin fragility and diseases. PMID:25561721

  11. Estrogens and aging skin

    PubMed Central

    Thornton, M. Julie

    2013-01-01

    Estrogen deficiency following menopause results in atrophic skin changes and acceleration of skin aging. Estrogens significantly modulate skin physiology, targeting keratinocytes, fibroblasts, melanocytes, hair follicles and sebaceous glands, and improve angiogenesis, wound healing and immune responses. Estrogen insufficiency decreases defense against oxidative stress; skin becomes thinner with less collagen, decreased elasticity, increased wrinkling, increased dryness and reduced vascularity. Its protective function becomes compromised and aging is associated with impaired wound healing, hair loss, pigmentary changes and skin cancer.   Skin aging can be significantly delayed by the administration of estrogen. This paper reviews estrogen effects on human skin and the mechanisms by which estrogens can alleviate the changes due to aging. The relevance of estrogen replacement, selective estrogen receptor modulators (SERMs) and phytoestrogens as therapies for diminishing skin aging is highlighted. Understanding estrogen signaling in skin will provide a basis for interventions in aging pathologies. PMID:24194966

  12. Skin age testing criteria: characterization of human skin structures by 500 MHz MRI multiple contrast and image processing.

    PubMed

    Sharma, Rakesh

    2010-07-21

    Ex vivo magnetic resonance microimaging (MRM) image characteristics are reported in human skin samples in different age groups. Human excised skin samples were imaged using a custom coil placed inside a 500 MHz NMR imager for high-resolution microimaging. Skin MRI images were processed for characterization of different skin structures. Contiguous cross-sectional T1-weighted 3D spin echo MRI, T2-weighted 3D spin echo MRI and proton density images were compared with skin histopathology and NMR peaks. In all skin specimens, epidermis and dermis thickening and hair follicle size were measured using MRM. Optimized parameters TE and TR and multicontrast enhancement generated better MRI visibility of different skin components. Within high MR signal regions near to the custom coil, MRI images with short echo time were comparable with digitized histological sections for skin structures of the epidermis, dermis and hair follicles in 6 (67%) of the nine specimens. Skin % tissue composition, measurement of the epidermis, dermis, sebaceous gland and hair follicle size, and skin NMR peaks were signatures of skin type. The image processing determined the dimensionality of skin tissue components and skin typing. The ex vivo MRI images and histopathology of the skin may be used to measure the skin structure and skin NMR peaks with image processing may be a tool for determining skin typing and skin composition.

  13. Skin age testing criteria: characterization of human skin structures by 500 MHz MRI multiple contrast and image processing

    NASA Astrophysics Data System (ADS)

    Sharma, Rakesh

    2010-07-01

    Ex vivo magnetic resonance microimaging (MRM) image characteristics are reported in human skin samples in different age groups. Human excised skin samples were imaged using a custom coil placed inside a 500 MHz NMR imager for high-resolution microimaging. Skin MRI images were processed for characterization of different skin structures. Contiguous cross-sectional T1-weighted 3D spin echo MRI, T2-weighted 3D spin echo MRI and proton density images were compared with skin histopathology and NMR peaks. In all skin specimens, epidermis and dermis thickening and hair follicle size were measured using MRM. Optimized parameters TE and TR and multicontrast enhancement generated better MRI visibility of different skin components. Within high MR signal regions near to the custom coil, MRI images with short echo time were comparable with digitized histological sections for skin structures of the epidermis, dermis and hair follicles in 6 (67%) of the nine specimens. Skin % tissue composition, measurement of the epidermis, dermis, sebaceous gland and hair follicle size, and skin NMR peaks were signatures of skin type. The image processing determined the dimensionality of skin tissue components and skin typing. The ex vivo MRI images and histopathology of the skin may be used to measure the skin structure and skin NMR peaks with image processing may be a tool for determining skin typing and skin composition.

  14. Raman spectroscopy of human skin: looking for a quantitative algorithm to reliably estimate human age

    NASA Astrophysics Data System (ADS)

    Pezzotti, Giuseppe; Boffelli, Marco; Miyamori, Daisuke; Uemura, Takeshi; Marunaka, Yoshinori; Zhu, Wenliang; Ikegaya, Hiroshi

    2015-06-01

    The possibility of examining soft tissues by Raman spectroscopy is challenged in an attempt to probe human age for the changes in biochemical composition of skin that accompany aging. We present a proof-of-concept report for explicating the biophysical links between vibrational characteristics and the specific compositional and chemical changes associated with aging. The actual existence of such links is then phenomenologically proved. In an attempt to foster the basics for a quantitative use of Raman spectroscopy in assessing aging from human skin samples, a precise spectral deconvolution is performed as a function of donors' ages on five cadaveric samples, which emphasizes the physical significance and the morphological modifications of the Raman bands. The outputs suggest the presence of spectral markers for age identification from skin samples. Some of them appeared as authentic "biological clocks" for the apparent exactness with which they are related to age. Our spectroscopic approach yields clear compositional information of protein folding and crystallization of lipid structures, which can lead to a precise identification of age from infants to adults. Once statistically validated, these parameters might be used to link vibrational aspects at the molecular scale for practical forensic purposes.

  15. Rejuvenation of Gene Expression Pattern of Aged Human Skin by Broadband Light Treatment: A Pilot Study

    PubMed Central

    Chang, Anne Lynn S; Bitter, Patrick H; Qu, Kun; Lin, Meihong; Rapicavoli, Nicole A; Chang, Howard Y

    2013-01-01

    Studies in model organisms suggest that aged cells can be functionally rejuvenated, but whether this concept applies to human skin is unclear. Here we apply 3′-end sequencing for expression quantification (“3-seq”) to discover the gene expression program associated with human photoaging and intrinsic skin aging (collectively termed “skin aging”), and the impact of broadband light (BBL) treatment. We find that skin aging was associated with a significantly altered expression level of 2,265 coding and noncoding RNAs, of which 1,293 became “rejuvenated” after BBL treatment; i.e., they became more similar to their expression level in youthful skin. Rejuvenated genes (RGs) included several known key regulators of organismal longevity and their proximal long noncoding RNAs. Skin aging is not associated with systematic changes in 3′-end mRNA processing. Hence, BBL treatment can restore gene expression pattern of photoaged and intrinsically aged human skin to resemble young skin. In addition, our data reveal, to our knowledge, a previously unreported set of targets that may lead to new insights into the human skin aging process. PMID:22931923

  16. Role of Age-Associated Alterations of the Dermal Extracellular Matrix Microenvironment in Human Skin Aging: A Mini-Review.

    PubMed

    Quan, Taihao; Fisher, Gary J

    2015-01-01

    Human skin is largely composed of a collagen-rich connective tissue, which provides structural and functional support. The collagen-rich connective tissue is produced, organized, and maintained by dermal fibroblasts. During aging, dermal collagen fibrils undergo progressive loss and fragmentation, leading to thin and structurally weakened skin. Age-related alterations of collagen fibrils impairs skin structure and function and creates a tissue microenvironment that promotes age-related skin diseases, such as delayed wound healing and skin cancer development. This mini-review describes cellular mechanisms that give rise to self-perpetuating, collagen fibril fragmentation that creates an age-associated dermal microenvironment, which contributes to decline of human skin function.

  17. AGE-RELATED GENE EXPRESSION CHANGES IN HUMAN SKIN FIBROBLASTS INDUCED BY MMS

    EPA Science Inventory

    Age-Related Gene Expression Changes In Human Skin Fibroblasts Induced By methyl methanesulfonate. Geremy W. Knapp, Alan H. Tennant, and Russell D. Owen. Environmental Carcinogenesis Division, National Health and Environmental Effects Research Laboratory, U. S. Environmental Prote...

  18. Collagen Fragmentation Promotes Oxidative Stress and Elevates Matrix Metalloproteinase-1 in Fibroblasts in Aged Human Skin

    PubMed Central

    Fisher, Gary J.; Quan, Taihao; Purohit, Trupta; Shao, Yuan; Cho, Moon Kyun; He, Tianyuan; Varani, James; Kang, Sewon; Voorhees, John J.

    2009-01-01

    Aged human skin is fragile because of fragmentation and loss of type I collagen fibrils, which confer strength and resiliency. We report here that dermal fibroblasts express increased levels of collagen-degrading matrix metalloproteinases-1 (MMP-1) in aged (>80 years old) compared with young (21 to 30 years old) human skin in vivo. Transcription factor AP-1 and α2β1 integrin, which are key regulators of MMP-1 expression, are also elevated in fibroblasts in aged human skin in vivo. MMP-1 treatment of young skin in organ culture causes fragmentation of collagen fibrils and reduces fibroblast stretch, consistent with reduced mechanical tension, as observed in aged human skin. Limited fragmentation of three-dimensional collagen lattices with exogenous MMP-1 also reduces fibroblast stretch and mechanical tension. Furthermore, fibroblasts cultured in fragmented collagen lattices express elevated levels of MMP-1, AP-1, and α2β1 integrin. Importantly, culture in fragmented collagen raises intracellular oxidant levels and treatment with antioxidant MitoQ10 significantly reduces MMP-1 expression. These data identify positive feedback regulation that couples age-dependent MMP-1-catalyzed collagen fragmentation and oxidative stress. We propose that this self perpetuating cycle promotes human skin aging. These data extend the current understanding of the oxidative theory of aging beyond a cellular-centric view to include extracellular matrix and the critical role that connective tissue microenvironment plays in the biology of aging. PMID:19116368

  19. Skin aging and dry skin.

    PubMed

    Hashizume, Hideo

    2004-08-01

    Skin aging appears to be the result of both scheduled and continuous "wear and tear" processes that damage cellular DNA and proteins. Two types of aging, chronological skin aging and photoaging, have distinct clinical and histological features. Chronological skin aging is a universal and inevitable process characterized primarily by physiologic alterations in skin function. In this case, keratinocytes are unable to properly terminally differentiate to form a functional stratum corneum, and the rate of formation of neutral lipids that contribute to the barrier function slows, causing dry, pale skin with fine wrinkles. In contrast, photoaging results from the UVR of sunlight and the damage thus becomes apparent in sun-exposed skin. Characteristics of this aging type are dry and sallow skin displaying fine wrinkles as well as deep furrows, resulting from the disorganization of epidermal and dermal components associated with elastosis and heliodermatitis. Understanding of the functions of the skin and the basic principles of moisturizer use and application is important for the prevention of skin aging. Successful treatment of dry skin with appropriate skin care products gives the impression of eternal youth.

  20. Ultrastructural age-related changes in the sensory corpuscles of the human genital skin.

    PubMed

    Tammaro, A; Parisella, F R; Cavallotti, C; Persechino, S; Cavallotti, C

    2013-01-01

    In human genital skin the majority of superficial sensory corpuscles is represented by glomerular corpuscles. These corpuscles show an own morphology. Our aim is to compare the ultra-structure of superficial sensory corpuscles in the penis skin of younger and older subjects. In this report the ultra-structure of the sensitive corpuscle in the penis skin of the younger and older subjects was compared, showing that the genital skin of the older humans contains more simple complexes than the younger ones. Our findings support the view that the age-related changes that can be observed in human glomerular genital corpuscles are consistent with an increase of the simple complexes and a strong decrease of the poly-lamellar one in the older people. These findings demonstrate that human genital corpuscles underwent age-related changes. Moreover our morphological findings can be correlated in relation to the clinical evolution of the sensitivity in the genital skin.

  1. An Analysis of Human Dorsal Hand Skin Texture Using Hyperspectral Imaging Technique for Assessing the Skin Aging Process.

    PubMed

    Calin, Mihaela Antonina; Parasca, Sorin Viorel; Calin, Marian Romeo; Petrescu, Emil

    2016-11-21

    Skin texture has become an important issue in recent research with applications in the cosmetic industry and medicine. In this paper, we analyzed the dependence of skin texture features on wavelength as well as on different parameters (age and gender) of human participants using grey-level co-occurrence matrix and hyperspectral imaging technique for a more accurate quantitative assessment of the aging process. A total of 42 healthy participants (men and women; age range, 20-70 years) was enrolled in this study. A region of interest was selected from the hyperspectral images. The results were analyzed in terms of texture using the gray-level co-occurrence matrix which generated four features (homogeneity, contrast, entropy, and correlation). The results showed that most of these features displayed variations with wavelength (the exception was entropy), with higher variations in women. Only correlation in both sexes and contrast in men proved to vary statistically significant with age, making them the targeted variables in future attempts to characterize aging skin using the complex method of hyperspectral imaging. In conclusion, by using hyperspectral imaging some measure of the degree of damage or the aging process of the hand skin can be obtained, mainly in terms of correlation values. At the present time, reasonable explanations that can link the process of skin aging and the above mentioned features could not be found, but deeper investigations are on the way.

  2. The effect of skin aging on the percutaneous penetration of chemicals through human skin

    SciTech Connect

    Roskos, K.V.

    1989-01-01

    Despite much research into the mechanisms of cutaneous aging and the identification of significant age-associated biological and biophysical changes within the skin, the question how does aging affect percutaneous absorption (PA) in vivo remains unanswered. The author has made in vivo measurements of PA in young (18-40 years) and old (> 65 years) subjects. Standard radiotracer methodology was employed and PA was quantified from the urinary excretion profiles of {sup 14}C radiolabel (corrected for incomplete renal elimination). Testosterone (TST), estradiol (EST), hydrocortisone (HC), benzoic acid (BA), acetylsalicylic acid (ASA) and caffeine (CAFF) have been studied. Penetration of HC, BA, ASA, and CAFF were significantly lower in aged subjects whereas TST and EST absorption were not distinguishable from the young controls. Thus it appears that aging can affect PA in vivo and that relatively hydrophilic compounds may be most sensitive. Work was done to elucidate whether the observations were related to documented skin aging changes. Cutaneous microcirculation efficiency suspected to decline with increasing age, could not be correlated with the observed penetration changes. However, in vivo infrared spectroscopic studies of aged stratum corneum (SC) reveal a decreased amount of epidermal lipid. The diminished lipid content implies a diminished dissolution medium for compounds administered to the skin surface. They hypothesize that the compounds most affected by a loss of SC lipids would be those compounds whose overall solubility is lowest (compounds with lower octanol-water partition coefficients, eg., HC, BA, ASA and CAFF). Conversely, a diminished lipid content may not affect dissolution into the SC of highly lipophilic compounds (e.g., TST and EST).

  3. Ontogeny and aging of the distal skin temperature rhythm in humans.

    PubMed

    Batinga, H; Martinez-Nicolas, A; Zornoza-Moreno, M; Sánchez-Solis, M; Larqué, E; Mondéjar, M T; Moreno-Casbas, M; García, F J; Campos, M; Rol, M A; Madrid, J A

    2015-01-01

    In circadian terms, human ontogeny is characterized by the emergence of a daily pattern, from a previous ultradian pattern, for most variables during the first 6 months of life. Circadian aging in humans is characterized by a phase advance, accompanied by rhythm fragmentation and flattening. Despite an expanding body of literature focused on distal skin temperature, little information is available about the ontogeny and practically nothing about age-related changes in this rhythm. Thus, the aim was to evaluate the degree of maturation and aging of the circadian pattern of distal skin temperature to identify those parameters that are modified throughout life and could be used to differentiate subjects according to their age. For this, distal skin temperature was measured in 197 volunteers (55 % women), including babies aged 15 days (30 subjects), 1 month (28 subjects), 3 months (31 subjects), and 6 months (10 subjects); young adults aged 19 years (37 subjects); middle-aged persons aged 46 years (27 subjects); older people aged 72 (34 subjects). Circadian system maturation was associated with an increase in amplitude and a reduction in skin temperature during sleep. During adulthood, women showed a more robust pattern (lower fragmentation, and higher night-time temperature, amplitude, circadian function index, and first harmonic relative power); however, these differences were lost with aging, a period of life that was consistently associated with a phase advance of the rhythm. In summary, distal skin temperature pattern can be used as a robust variable to discern between different ages throughout the life.

  4. Retinoids suppress cysteine-rich protein 61 (CCN1), a negative regulator of collagen homeostasis, in skin equivalent cultures and aged human skin in vivo.

    PubMed

    Quan, Taihao; Qin, Zhaoping; Shao, Yuan; Xu, Yiru; Voorhees, John J; Fisher, Gary J

    2011-07-01

    Alterations in connective tissue collagen are prominent features of both chronologically aged and photoaged (ageing because of sun exposure) human skin. These age-related abnormalities are mediated in part by cysteine-rich protein 61 (CCN1). CCN1 is elevated in the dermis of both chronologically aged and photoaged human skin in vivo and promotes aberrant collagen homeostasis by down-regulating type I collagen, the major structural protein in skin, and promoting collagen degradation. Vitamin A and its metabolites have been shown to improve chronologically aged and photoaged skin by promoting deposition of new collagen and preventing its degradation. Here, we investigated regulation of CCN1 expression by retinoids in skin equivalent cultures and chronologically aged and photoaged human skin in vivo. In skin equivalent cultures, all-trans retinoic acid (RA), the major bioactive form of vitamin A in skin, significantly increased type I procollagen and reduced collagenase (matrix metalloproteinases-1, MMP-1). Addition of recombinant human CCN1 to skin equivalent cultures significantly reduced type I procollagen and increased MMP-1. Importantly, RA significantly reduced CCN1 expression in skin equivalent cultures. Topical treatment with retinol (vitamin A, 0.4%) for 7days significantly reduced CCN1 mRNA and protein expression in both chronologically aged (80+years) and photoaged human skin in vivo, compared to vehicle-treated skin. These data indicate that the mechanism by which retinoids improve aged skin, through increased collagen production, involves down-regulation of CCN1.

  5. Detection of advanced glycation end products (AGEs) on human skin by in vivo confocal Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Martin, A. A.; Pereira, L.; Ali, S. M.; Pizzol, C. D.; Tellez, C. A.; Favero, P. P.; Santos, L.; da Silva, V. V.; Praes, C. E. O.

    2016-03-01

    The aging process involves the reduction in the production of the major components of skin tissue. During intrinsic aging and photoaging processes, in dermis of human skin, fibroblasts become senescent and have decreased activity, which produce low levels of collagen. Moreover, there is accumulation of advanced glycation end products (AGEs). AGEs have incidence in the progression of age-related diseases, principally in diabetes mellitus and in Alzheimer's diseases. AGEs causes intracellular damage and/or apoptosis leading to an increase of the free radicals, generating a crosslink with skin proteins and oxidative stress. The aim of this study is to detect AGEs markers on human skin by in vivo Confocal Raman spectroscopy. Spectra were obtained by using a Rivers Diagnostic System, 785 nm laser excitation and a CCD detector from the skin surface down to 120 μm depth. We analyzed the confocal Raman spectra of the skin dermis of 30 women volunteers divided into 3 groups: 10 volunteers with diabetes mellitus type II, 65-80 years old (DEW); 10 young healthy women, 20-33 years old (HYW); and 10 elderly healthy women, 65-80 years old (HEW). Pentosidine and glucosepane were the principally identified AGEs in the hydroxyproline and proline Raman spectral region (1000-800 cm-1), in the 1.260-1.320 cm-1 region assignable to alpha-helical amide III modes, and in the Amide I region. Pentosidine and glucosepane calculated vibrational spectra were performed through Density Functional Theory using the B3LYP functional with 3-21G basis set. Difference between the Raman spectra of diabetic elderly women and healthy young women, and between healthy elderly women and healthy young women were also obtained with the purpose of identifying AGEs Raman bands markers. AGEs peaks and collagen changes have been identified and used to quantify the glycation process in human skin.

  6. Skin Care and Aging

    MedlinePlus

    ... version of this page please turn Javascript on. Skin Care and Aging How Aging Affects Skin Your skin changes with age. It becomes thinner, ... to make it feel and look better. Dry Skin and Itching Click for more information Many older ...

  7. In vivo quantification of human dermal skin aging using SHG and autofluorescence

    NASA Astrophysics Data System (ADS)

    Puschmann, Stefan; Rahn, Christian-Dennis; Wenck, Horst; Gallinat, Stefan; Fischer, Frank

    2012-03-01

    There are visible changes during skin aging. In the extracellular matrix these changes referred to as intrinsic aging (skin areas not exposed to sunlight) and extrinsic aging can be measured using various methods, such as subjective clinical evaluation, histology and molecular analysis. In this study we developed a new parameter for the non-invasive quantitative determination of dermal skin aging utilizing a five-dimensional intravital tomography (5D-IVT). This device, also known as 5D - multi-photon laser scanning microscopy, is a powerful tool to investigate (photo)aging-associated alterations in vivo. Structural alterations in the dermis of extrinsically aged (chronically sun-exposed) and intrinsically aged (sun-protected) human skin were recorded utilizing the collagen-specific second harmonic generation (SHG) signal and the elastin-specific autofluorescence (AF) signal. Recording took place in young and elderly volunteers. The resulting images were processed in order to gain the elastin percentage and the collagen percentage per image. Then, the elastin - to - collagen ratio (ELCOR) was calculated. With respect to volar forearm skin, the ELCOR significantly increased with age. In elderly volunteers, the ELCOR value calculated for the chronically sun-exposed temple area was significantly augmented compared with the sun-protected upper arm area. Based on 5D-IVT we introduce the ELCOR as a new means to quantify age-associated alterations in the extracellular matrix of in vivo human skin. This novel parameter is compared to the currently used "SHG to AF aging index" of the dermis (SAAID).

  8. Peripheral mechanisms of thermoregulatory control of skin blood flow in aged humans

    PubMed Central

    Kenney, W. Larry

    2010-01-01

    Human skin blood flow is controlled via dual innervation from the sympathetic nervous system. Reflex cutaneous vasoconstriction and vasodilation are both impaired with primary aging, rendering the aged more vulnerable to hypothermia and cardiovascular complications from heat-related illness. Age-related alterations in the thermoregulatory control of skin blood flow occur at multiple points along the efferent arm of the reflex, including 1) diminished sympathetic outflow, 2) altered presynaptic neurotransmitter synthesis, 3) reduced vascular responsiveness, and 4) impairments in downstream (endothelial and vascular smooth muscle) second-messenger signaling. This mechanistic review highlights some of the recent findings in the area of aging and the thermoregulatory control of skin blood flow. PMID:20413421

  9. Age-related changes in expression and function of Toll-like receptors in human skin.

    PubMed

    Iram, Nousheen; Mildner, Michael; Prior, Marion; Petzelbauer, Peter; Fiala, Christian; Hacker, Stefan; Schöppl, Alice; Tschachler, Erwin; Elbe-Bürger, Adelheid

    2012-11-01

    Toll-like receptors (TLRs) initiate innate immune responses and direct subsequent adaptive immunity. They play a major role in cutaneous host defense against micro-organisms and in the pathophysiology of several inflammatory skin diseases. To understand the role of TLRs in the acquisition of immunological competence, we conducted a comprehensive study to evaluate TLR expression and function in the developing human skin before and after birth and compared it with adults. We found that prenatal skin already expresses the same spectrum of TLRs as adult skin. Strikingly, many TLRs were significantly higher expressed in prenatal (TLRs 1-5) and infant and child (TLRs 1 and 3) skin than in adult skin. Surprisingly, neither dendritic cell precursors in prenatal skin nor epidermal Langerhans cells and dermal dendritic cells in adult skin expressed TLRs 3 and 6, whereas the staining pattern and intensity of both TLRs in fetal basal keratinocytes was almost comparable to those of adults. Stimulation of primary human keratinocytes from fetal, neonatal and adult donors with selected TLR agonists revealed that the synthetic TLR3 ligand poly (I:C) specifically, mimicking viral double-stranded RNA, induced a significantly enhanced secretion of CXCL8/IL8, CXCL10/IP-10 and TNFα in fetal and neonatal keratinocytes compared with adult keratinocytes. This study demonstrates quantitative age-specific modifications in TLR expression and innate skin immune reactivity in response to TLR activation. Thus, antiviral innate immunity already in prenatal skin may contribute to protect the developing human body from viral infections in utero in a scenario where the adaptive immune system is not yet fully functional.

  10. Nested PCR-denaturing gradient gel electrophoresis analysis of human skin microbial diversity with age.

    PubMed

    Li, Wei; Han, Lei; Yu, Pengbo; Ma, Chaofeng; Wu, Xiaokang; Xu, Jiru

    2014-01-01

    To determine whether the composition and structure of skin microbiota differ with age, cutaneous bacteria were isolated from the axillary fossa of 37 healthy human adults in two age groups (old people and young adults). Bacterial genomic DNA was extracted and characterized by nested PCR-denaturing gradient gel electrophoresis (PCR-DGGE) with primers specifically targeting V3 region of the 16S rRNA gene. The excised gel bands were sequenced to identify bacterial categories. The total bacteria, Staphylococcus spp., Staphylococcus epidermidis and Corynebacterium spp. were further enumerated by quantitative PCR. There were no significant differences in the species diversity profiles between age groups. The similarity index was lower across age groups than that it was intra-group. This indicates that the composition of skin flora is more similar to others of the same age than across age groups. While Staphylococcus spp. and Corynebacterium spp. were the dominant bacteria in both groups, sequencing and quantitative PCR revealed that skin bacterial composition differed by age. The copy number of total bacteria and Corynebacterium spp. were significantly lower in younger subjects, whereas there were no statistical differences in the quantity of Staphylococcus spp. and Staphylococcus epidermidis. These results suggest that the skin flora undergo both quantitative and qualitative changes related to aging.

  11. Collagen cross-linking in sun-exposed and unexposed sites of aged human skin

    NASA Technical Reports Server (NTRS)

    Yamauchi, M.; Prisayanh, P.; Haque, Z.; Woodley, D. T.

    1991-01-01

    A recently described nonreducible, acid-heat stable compound, histidinohydroxylysinonorleucine (HHL), is a collagen cross-link isolated from mature skin tissue. Its abundance is related to chronologic aging of skin. The present communication describes the quantity of HHL from aged human skin of the same individuals in sun-exposed (wrist) and unexposed (buttock) sites. Punch biopsies were obtained from these sites from nine people of age 60 or older. HHL contents (moles/mole of collagen) at these sites were for wrist 0.13 +/- 0.07 and for buttock 0.69 +/- 0.17 (mean +/- SD, p less than 0.001). In addition, it was found that acute irradiation of the cross-linked peptides with UVA (up to 250 J/cm2) and UVB (up to 1 J/cm2) had no effect on HHL structure. The same treatment significantly degraded another nonreducible, stable collagen cross-link, pyridinoline. The results suggest that chronic sunlight exposure may be associated with an impediment to normal maturation of human dermal collagen resulting in tenuous amount of HHL. Thus, the process of photoaging in dermal collagen is different from that of chronologic aging in human skin.

  12. Sympathetic modulation of sensory nerve activity with age: human and rodent skin models.

    PubMed

    Khalil, Z; LeVasseur, S; Merhi, M; Helme, R D

    1997-11-01

    1. Sensory nerves serve an afferent role and mediate neurogenic components of inflammation and tissue repair via an axon reflex release of sensory peptides at sites of injury. Dysfunction of these nerves with age could contribute to delayed tissue healing. 2. Complementary animal and human skin models were used in the present studies to investigate changes in the modulation of sensory nerve function by sympathetic efferents during ageing. Laser Doppler flowmetry was used to monitor neurogenic skin vascular responses. 3. The animal model used skin of the hind footpad of anaesthetized rats combined with electrical stimulation of the sciatic nerve, while the human model comprised capsaicin electrophoresis to the volar surface of the forearm. Sympathetic modulation was effected by systemic phentolamine pretreatment in animals and local application in the human model. 4. The results obtained from the human model confirmed the reported decline in sensory nerve function and showed no change in sympathetic modulation with age. The results from the animal model confirm and expand results obtained from the human model. 5. The use of low (5 Hz) and high (15 Hz) frequency electrical stimulation (20 V, 2 ms for 1 min) revealed a preferential response of aged sensory nerves to low-frequency electrical stimulation parameters with differential sympathetic modulation that is dependent on the frequency of stimulation.

  13. Consistency of the Proteome in Primary Human Keratinocytes With Respect to Gender, Age, and Skin Localization*

    PubMed Central

    Sprenger, Adrian; Weber, Sebastian; Zarai, Mostafa; Engelke, Rudolf; Nascimento, Juliana M.; Gretzmeier, Christine; Hilpert, Martin; Boerries, Melanie; Has, Cristina; Busch, Hauke; Bruckner-Tuderman, Leena; Dengjel, Jörn

    2013-01-01

    Keratinocytes account for 95% of all cells of the epidermis, the stratified squamous epithelium forming the outer layer of the skin, in which a significant number of skin diseases takes root. Immortalized keratinocyte cell lines are often used as research model systems providing standardized, reproducible, and homogenous biological material. Apart from that, primary human keratinocytes are frequently used for medical studies because the skin provides an important route for drug administration and is readily accessible for biopsies. However, comparability of these cell systems is not known. Cell lines may undergo phenotypic shifts and may differ from the in vivo situation in important aspects. Primary cells, on the other hand, may vary in biological functions depending on gender and age of the donor and localization of the biopsy specimen. Here we employed metabolic labeling in combination with quantitative mass spectrometry-based proteomics to assess A431 and HaCaT cell lines for their suitability as model systems. Compared with cell lines, comprehensive profiling of the primary human keratinocyte proteome with respect to gender, age, and skin localization identified an unexpected high proteomic consistency. The data were analyzed by an improved ontology enrichment analysis workflow designed for the study of global proteomics experiments. It enables a quick, comprehensive and unbiased overview of altered biological phenomena and links experimental data to literature. We guide through our workflow, point out its advantages compared with other methods and apply it to visualize differences of cell lines compared with primary human keratinocytes. PMID:23722187

  14. Aging of human skin: review of a mechanistic model and first experimental data.

    PubMed

    Giacomoni, P U; Declercq, L; Hellemans, L; Maes, D

    2000-04-01

    The physical, chemical, and biochemical factors that accelerate skin aging have been proposed to activate a self-maintained microinflammatory process, one of the expected end results of which is an imbalance in the turnover of macromolecules in the dermis. Surface peroxides are recognized as controllable factors of skin aging, and their accumulation is attributed to environmentally induced impairment of defense enzymes. Topical application of antioxidants decreases the rate at which skin elasticity and skin thickness are modified.

  15. Oral sapropterin acutely augments reflex vasodilation in aged human skin through nitric oxide-dependent mechanisms.

    PubMed

    Stanhewicz, Anna E; Alexander, Lacy M; Kenney, W Larry

    2013-10-01

    Functional constitutive nitric oxide synthase (NOS) and its cofactor tetrahydrobiopterin (BH4) are required for full reflex cutaneous vasodilation and are attenuated in primary aging. Acute, locally administered BH4 increases reflex vasodilation through NO-dependent mechanisms in aged skin. We hypothesized that oral sapropterin (Kuvan, shelf-stable pharmaceutical formulation of BH4) would augment reflex vasodilation in aged human skin during hyperthermia. Nine healthy human subjects (76 ± 1 yr) ingested sapropterin (10 mg/kg) or placebo in a randomized double-blind crossover design. Venous blood samples were collected prior to, and 3 h following, ingestion of sapropterin for measurement of plasma BH4. Three intradermal microdialysis fibers were placed in the forearm skin for local delivery of 1) lactated Ringer's solution, 2) 10 mM BH4, and 3) 20 mM N(G)-nitro-l-arginine methyl ester (l-NAME) to inhibit NOS. Red cell flux was measured at each site by laser-Doppler flowmetry (LDF) as reflex vasodilation was induced using a water-perfused suit. At 1°C rise in oral temperature, mean body temperature was clamped and 20 mM l-NAME was perfused at each site. Cutaneous vascular conductance was calculated (CVC = LDF/MAP) and expressed as a percentage of maximum (%CVCmax 28 mM sodium nitroprusside and local heat 43°C). Plasma concentrations of BH4 were significantly elevated 3 h after ingestion of sapropterin (0 h: 19.1 ± 2 pmol/ml vs. 3 h: 43.8 ± 3 pmol/ml; P < 0.001). Sapropterin increased NO-dependent vasodilation at control site (placebo: 14 ± 1 %CVCmax vs. sapropterin: 25 ± 4 %CVCmax; P = 0.004). Local BH4 administration increased NO-dependent vasodilation compared with control in placebo trials only (control: 14 ± 1 %CVCmax vs. BH4-treated: 24 ± 3 %CVCmax; P = 0.02). These data suggest oral sapropterin increases bioavailable BH4 in aged skin microvasculature sufficiently to increase NO synthesis through NOS and that sapropterin may be a viable intervention to

  16. Stressed out mitochondria: the role of mitochondria in ageing and cancer focussing on strategies and opportunities in human skin.

    PubMed

    Tulah, Asif S; Birch-Machin, Mark A

    2013-09-01

    Mitochondrial DNA damage has been used as a successful and unique biomarker of tissue stress. A valuable example of this is sun damage in human skin which leads to ageing and skin cancer. The skin is constantly exposed to the harmful effects of sunlight, such as ultraviolet radiation, which causes it to age with observable characteristic features as well as clinical precancerous lesions and skin cancer. Formation of free radicals by the sun's harmful rays which contribute to oxidative stress has been linked to the induction of deletions and mutations in the mitochondrial DNA. These markers of mitochondrial DNA damage have been proposed to contribute to the mechanisms of ageing in many tissues including skin and are associated with many diseases including cancer. In this article we highlight the role of this important organelle in ageing and cancer with particular emphasis on experimental strategies in the skin.

  17. Oral sapropterin augments reflex vasoconstriction in aged human skin through noradrenergic mechanisms.

    PubMed

    Stanhewicz, Anna E; Alexander, Lacy M; Kenney, W Larry

    2013-10-01

    Reflex vasoconstriction is attenuated in aged skin due to a functional loss of adrenergic vasoconstriction. Bioavailability of tetrahydrobiopterin (BH4), an essential cofactor for catecholamine synthesis, is reduced with aging. Locally administered BH4 increases vasoconstriction through adrenergic mechanisms in aged human skin. We hypothesized that oral sapropterin (Kuvan, a pharmaceutical BH4) would augment vasoconstriction elicited by whole-body cooling and tyramine perfusion in aged skin. Ten healthy subjects (age 75 ± 2 yr) ingested sapropterin (10 mg/kg) or placebo in a randomized, double-blind crossover design. Venous blood samples were collected prior to, and 3 h following ingestion. Three intradermal microdialysis fibers were placed in the forearm skin for local delivery of 1) lactated Ringer, 2) 5 mM BH4, and 3) 5 mM yohimbine + 1 mM propranolol (Y+P; to inhibit adrenergic vasoconstriction). Red cell flux was measured at each site by laser-Doppler flowmetry (LDF) as reflex vasoconstriction was induced by lowering and then clamping whole-body skin temperature (Tsk) using a water-perfused suit. Following whole-body cooling, subjects were rewarmed and 1 mM tyramine was perfused at each site to elicit endogenous norepinephrine release from the perivascular nerve terminal. Cutaneous vascular conductance was calculated as CVC = LDF/mean arterial pressure and expressed as change from baseline (ΔCVC). Plasma BH4 was elevated 3 h after ingestion of sapropterin (43.8 ± 3 vs. 19.1 ± 2 pmol/ml; P < 0.001). Sapropterin increased reflex vasoconstriction at the Ringer site at Tsk ≤ 32.5°C (P < 0.05). Local BH4 perfusion augmented reflex vasoconstriction at Tsk ≤ 31.5°C with placebo treatment only (P < 0.05). There was no treatment effect on reflex vasoconstriction at the BH4-perfused or Y+P-perfused sites. Sapropterin increased pharmacologically induced vasoconstriction at the Ringer site (-0.19 ± 0.03 vs. -0.08 ± 0.02 ΔCVC; P = 0.01). There was no

  18. Genetics and skin aging

    PubMed Central

    Makrantonaki, Evgenia; Bekou, Vassiliki; Zouboulis, Christos C.

    2012-01-01

    Skin aging is a complex process and underlies multiple influences with the probable involvement of heritable and various environmental factors. Several theories have been conducted regarding the pathomechanisms of aged skin, however fundamental mechanisms still remain poorly understood. This article addresses the influence of genetics on skin aging and in particular deals with the differences observed in ethnic populations and between both genders. Recent studies indicate that male and female aged skin differs as far as the type, the consistency and the sensitivity to external factors is concerned. The same has been also documented between elderly people of different origin. Consequently, the aging process taking place in both genders and in diverse ethnic groups should be examined separately and products specialized to each population should be developed in order to satisfy the special needs. PMID:23467395

  19. Anti-Aging Potential of Phytoextract Loaded-Pharmaceutical Creams for Human Skin Cell Longetivity.

    PubMed

    Jadoon, Saima; Karim, Sabiha; Bin Asad, Muhammad Hassham Hassan; Akram, Muhammad Rouf; Khan, Abida Kalsoom; Malik, Arif; Chen, Chunye; Murtaza, Ghulam

    2015-01-01

    The exposure to ultraviolet radiations (UVR) is the key source of skin sunburn; it may produce harmful entities, reactive oxygen species (ROS), leading to aging. The skin can be treated and protected from the injurious effects of ROS by using various pharmaceutical formulations, such as cream. Cream can be loaded with antioxidants to quench ROS leading to photo-protective effects. Moreover, modern medicines depend on ethnobotanicals for protection or treatment of human diseases. This review article summarizes various in vivo antioxidant studies on herbal creams loaded with phyto-extracts. These formulations may serve as cosmeceuticals to protect skin against injurious effects of UVR. The botanicals studied for dermatologic use in cream form include Acacia nilotica, Benincasa hispida, Calendula officinalis, Camellia sinensis, Camellia sinensis, Nelumbo nucifera, Capparis decidua, Castanea sativa, Coffea arabica, Crocus sativus, Emblica officinalis Gaertn, Foeniculum vulgare, Hippophae rhamnoides, Lithospermum erythrorhizon, Malus domestica, Matricaria chamomilla L., Moringa oleifera, Morus alba, Ocimum basilicum, Oryza sativa, Polygonum minus, Punica granatum, Silybum marianum, Tagetes erecta Linn., Terminalia chebula, Trigonella foenum-graecum, and Vitis vinifera. The observed anti-aging effects of cream formulations could be an outcome of a coordinating action of multiple constituents. Of numerous botanicals, the phenolic acids and flavonoids appear effective against UVR-induced damage; however the evidence-based studies for their anti-aging effects are still needed.

  20. Anti-Aging Potential of Phytoextract Loaded-Pharmaceutical Creams for Human Skin Cell Longetivity

    PubMed Central

    Jadoon, Saima; Karim, Sabiha; Asad, Muhammad Hassham Hassan Bin; Akram, Muhammad Rouf; Kalsoom Khan, Abida; Malik, Arif; Chen, Chunye; Murtaza, Ghulam

    2015-01-01

    The exposure to ultraviolet radiations (UVR) is the key source of skin sunburn; it may produce harmful entities, reactive oxygen species (ROS), leading to aging. The skin can be treated and protected from the injurious effects of ROS by using various pharmaceutical formulations, such as cream. Cream can be loaded with antioxidants to quench ROS leading to photo-protective effects. Moreover, modern medicines depend on ethnobotanicals for protection or treatment of human diseases. This review article summarizes various in vivo antioxidant studies on herbal creams loaded with phyto-extracts. These formulations may serve as cosmeceuticals to protect skin against injurious effects of UVR. The botanicals studied for dermatologic use in cream form include Acacia nilotica, Benincasa hispida, Calendula officinalis, Camellia sinensis, Camellia sinensis, Nelumbo nucifera, Capparis decidua, Castanea sativa, Coffea arabica, Crocus sativus, Emblica officinalis Gaertn, Foeniculum vulgare, Hippophae rhamnoides, Lithospermum erythrorhizon, Malus domestica, Matricaria chamomilla L., Moringa oleifera, Morus alba, Ocimum basilicum, Oryza sativa, Polygonum minus, Punica granatum, Silybum marianum, Tagetes erecta Linn., Terminalia chebula, Trigonella foenum-graecum, and Vitis vinifera. The observed anti-aging effects of cream formulations could be an outcome of a coordinating action of multiple constituents. Of numerous botanicals, the phenolic acids and flavonoids appear effective against UVR-induced damage; however the evidence-based studies for their anti-aging effects are still needed. PMID:26448818

  1. Characterizing facial skin ageing in humans: disentangling extrinsic from intrinsic biological phenomena.

    PubMed

    Trojahn, Carina; Dobos, Gabor; Lichterfeld, Andrea; Blume-Peytavi, Ulrike; Kottner, Jan

    2015-01-01

    Facial skin ageing is caused by intrinsic and extrinsic mechanisms. Intrinsic ageing is highly related to chronological age. Age related skin changes can be measured using clinical and biophysical methods. The aim of this study was to evaluate whether and how clinical characteristics and biophysical parameters are associated with each other with and without adjustment for chronological age. Twenty-four female subjects of three age groups were enrolled. Clinical assessments (global facial skin ageing, wrinkling, and sagging), and biophysical measurements (roughness, colour, skin elasticity, and barrier function) were conducted at both upper cheeks. Pearson's correlations and linear regression models adjusted for age were calculated. Most of the measured parameters were correlated with chronological age (e.g., association with wrinkle score, r = 0.901) and with each other (e.g., residual skin deformation and wrinkle score, r = 0.606). After statistical adjustment for age, only few associations remained (e.g., mean roughness (R z ) and luminance (L (*)),  β = -0.507, R (2) = 0.377). Chronological age as surrogate marker for intrinsic ageing has the most important influence on most facial skin ageing signs. Changes in skin elasticity, wrinkling, sagging, and yellowness seem to be caused by additional extrinsic ageing.

  2. Investigation of age-related decline of microfibril-associated glycoprotein-1 in human skin through immunohistochemistry study.

    PubMed

    Zheng, Qian; Chen, Siming; Chen, Ying; Lyga, John; Wyborski, Russell; Santhanam, Uma

    2013-01-01

    During aging, the reduction of elastic and collagen fibers in dermis can lead to skin atrophy, fragility, and aged appearance, such as increased facial wrinkling and sagging. Microfibril-associated glycoprotein-1 (MAGP-1) is an extracellular matrix protein critical for elastic fiber assembly. It integrates and stabilizes the microfibril and elastin matrix network that helps the skin to endure mechanical stretch and recoil. However, the observation of MAGP-1 during skin aging and its function in the dermis has not been established. To better understand age-related changes in the dermis, we investigated MAGP-1 during skin aging and photoaging, using a combination of in vitro and in vivo studies. Gene expression by microarray was performed using human skin biopsies from young and aged female donors. In addition, immunofluorescence analysis on the MAGP-1 protein was performed in dermal fibroblast cultures and in human skin biopsies. Specific antibodies against MAGP-1 and fibrillin-1 were used to examine protein expression and extracellular matrix structure in the dermis via biopsies from donors of multiple age groups. A reduction of the MAGP-1 gene and protein levels were observed in human skin with increasing age and photoexposure, indicating a loss of the functional MAGP-1 fiber network and a lack of structural support in the dermis. Loss of MAGP-1 around the hair follicle/pore areas was also observed, suggesting a possible correlation between MAGP-1 loss and enlarged pores in aged skin. Our findings demonstrate that a critical "pre-elasticity" component, MAGP-1, declines with aging and photoaging. Such changes may contribute to age-related loss of dermal integrity and perifollicular structural support, which may lead to skin fragility, sagging, and enlarged pores.

  3. Age-associated increase of skin fibroblast-derived prostaglandin E2 contributes to reduced collagen levels in elderly human skin

    PubMed Central

    Li, Yong; Lei, Dan; Swindell, William R; Xia, Wei; Weng, Shinuo; Fu, Jianping; Worthen, Christal A; Okubo, Toru; Johnston, Andrew; Gudjonsson, Johann E; Voorhees, John J; Fisher, Gary J

    2015-01-01

    Production of type I collagen declines during aging, leading to skin thinning and impaired function. Prostaglandin E2 (PGE2) is a pleiotropic lipid mediator that is synthesized from arachidonic acid by the sequential actions of cyclooxygenases (COX) and PGE synthases (PTGES). PGE2 inhibits collagen production by fibroblasts in vitro. We report that PTGES1 and COX2 progressively increase with aging in sun-protected human skin. PTGES1 and COX2 mRNA was increased 3.4-fold and 2.7-fold, respectively, in the dermis of elderly (>80 years) versus young (21-30 years) individuals. Fibroblasts were the major cell source of both enzymes. PGE2 levels were increased 70% in elderly skin. Fibroblasts in aged skin display reduced spreading due to collagen fibril fragmentation. To investigate the relationship between spreading and PGE2 synthesis, fibroblasts were cultured on micropost arrays or hydrogels of varying mechanical compliance. Reduced spreading/mechanical force resulted in increased expression of both PTGES1 and COX2 and elevated levels of PGE2. Inhibition of PGE2 synthesis by diclofenac enhanced collagen production in skin organ cultures. These data suggest that reduced spreading/mechanical force of fibroblasts in aged skin elevates PGE2 production, contributing to reduced collagen production. Inhibition of PGE2 production may be therapeutically beneficial for combating age-associated collagen deficit in human skin. PMID:25905589

  4. Instrumental evaluation of anti-aging effects of cosmetic formulations containing palmitoyl peptides, Silybum marianum seed oil, vitamin E and other functional ingredients on aged human skin

    PubMed Central

    Hahn, Hyung Jin; Jung, Ho Jung; Schrammek-Drusios, Med Christine; Lee, Sung Nae; Kim, Ji-Hyun; Kwon, Seung Bin; An, In-Sook; An, Sungkwan; Ahn, Kyu Joong

    2016-01-01

    Anti-aging cosmetics are widely used for improving signs of aged skin such as skin wrinkles, decreased elasticity, low dermal density and yellow skin tone. The present study evaluated the effects of cosmetic formulations, eye cream and facial cream, containing palmitoyl peptides, Silybum marianum (S. marianum) seed oil, vitamin E and other functional ingredients on the improvement of facial wrinkles, elasticity, dermal density and skin tone after 4 weeks period of application on aged human skin. Healthy volunteers (n=20) with aged skin were recruited to apply the test materials facially twice per day for 4 weeks. Skin wrinkles, elasticity, dermal density and skin tone were measured instrumentally for assessing the improvement of skin aging. All the measurements were conducted prior to the application of test materials and at 2 and 4 weeks of treatment. Crow's feet wrinkles were decreased 5.97% after 2 weeks of test material application and 14.07% after 4 weeks of application in comparison of pre-application. Skin elasticity was increased 6.81% after 2 weeks and 8.79% after 4 weeks. Dermal density was increased 16.74% after 2 weeks and 27.63% after 4 weeks. With the L* value indicating skin brightness and the a* value indicating erythema (redness), the results showed that brightness was increased 1.70% after 2 weeks and 2.14% after 4 weeks, and erythema was decreased 10.45% after 2 weeks and 22.39% after 4 weeks. Hence, the test materials appear to exert some degree of anti-aging effects on aged human skin. There were no abnormal skin responses from the participants during the trial period. We conclude that the facial and eye cream containing palmitoyl peptides and S. marianum seed oil, vitamin E and other ingredients have effects on the improvement of facial wrinkles, elasticity, dermal density and skin tone. PMID:27446338

  5. Instrumental evaluation of anti-aging effects of cosmetic formulations containing palmitoyl peptides, Silybum marianum seed oil, vitamin E and other functional ingredients on aged human skin.

    PubMed

    Hahn, Hyung Jin; Jung, Ho Jung; Schrammek-Drusios, Med Christine; Lee, Sung Nae; Kim, Ji-Hyun; Kwon, Seung Bin; An, In-Sook; An, Sungkwan; Ahn, Kyu Joong

    2016-08-01

    Anti-aging cosmetics are widely used for improving signs of aged skin such as skin wrinkles, decreased elasticity, low dermal density and yellow skin tone. The present study evaluated the effects of cosmetic formulations, eye cream and facial cream, containing palmitoyl peptides, Silybum marianum (S. marianum) seed oil, vitamin E and other functional ingredients on the improvement of facial wrinkles, elasticity, dermal density and skin tone after 4 weeks period of application on aged human skin. Healthy volunteers (n=20) with aged skin were recruited to apply the test materials facially twice per day for 4 weeks. Skin wrinkles, elasticity, dermal density and skin tone were measured instrumentally for assessing the improvement of skin aging. All the measurements were conducted prior to the application of test materials and at 2 and 4 weeks of treatment. Crow's feet wrinkles were decreased 5.97% after 2 weeks of test material application and 14.07% after 4 weeks of application in comparison of pre-application. Skin elasticity was increased 6.81% after 2 weeks and 8.79% after 4 weeks. Dermal density was increased 16.74% after 2 weeks and 27.63% after 4 weeks. With the L* value indicating skin brightness and the a* value indicating erythema (redness), the results showed that brightness was increased 1.70% after 2 weeks and 2.14% after 4 weeks, and erythema was decreased 10.45% after 2 weeks and 22.39% after 4 weeks. Hence, the test materials appear to exert some degree of anti-aging effects on aged human skin. There were no abnormal skin responses from the participants during the trial period. We conclude that the facial and eye cream containing palmitoyl peptides and S. marianum seed oil, vitamin E and other ingredients have effects on the improvement of facial wrinkles, elasticity, dermal density and skin tone.

  6. Skin anti-aging strategies

    PubMed Central

    Ganceviciene, Ruta; Liakou, Aikaterini I.; Theodoridis, Athanasios; Makrantonaki, Evgenia; Zouboulis, Christos C.

    2012-01-01

    Skin aging is a complex biological process influenced by a combination of endogenous or intrinsic and exogenous or extrinsic factors. Because of the fact that skin health and beauty is considered one of the principal factors representing overall “well-being” and the perception of “health” in humans, several anti-aging strategies have been developed during the last years. It is the intention of this article to review the most important anti-aging strategies that dermatologists have nowadays in hand, including including preventive measurements, cosmetological strategies, topical and systemic therapeutic agents and invasive procedures. PMID:23467476

  7. Skin anti-aging strategies.

    PubMed

    Ganceviciene, Ruta; Liakou, Aikaterini I; Theodoridis, Athanasios; Makrantonaki, Evgenia; Zouboulis, Christos C

    2012-07-01

    Skin aging is a complex biological process influenced by a combination of endogenous or intrinsic and exogenous or extrinsic factors. Because of the fact that skin health and beauty is considered one of the principal factors representing overall "well-being" and the perception of "health" in humans, several anti-aging strategies have been developed during the last years. It is the intention of this article to review the most important anti-aging strategies that dermatologists have nowadays in hand, including including preventive measurements, cosmetological strategies, topical and systemic therapeutic agents and invasive procedures.

  8. Molecular aspects of skin ageing.

    PubMed

    Naylor, Elizabeth C; Watson, Rachel E B; Sherratt, Michael J

    2011-07-01

    Ageing of human skin may result from both the passage of time (intrinsic ageing) and from cumulative exposure to external influences (extrinsic ageing) such as ultraviolet radiation (UVR) which promote wrinkle formation and loss of tissue elasticity. Whilst both ageing processes are associated with phenotypic changes in cutaneous cells, the major functional manifestations of ageing occur as a consequence of structural and compositional remodeling of normally long-lived dermal extracellular matrix proteins. This review briefly considers the effects of ageing on dermal collagens and proteoglycans before focusing on the mechanisms, functional consequences and treatment of elastic fibre remodeling in ageing skin. The early stages of photoageing are characterised by the differential degradation of elastic fibre proteins and whilst the activity of extracellular matrix proteases is increased in photoexposed skin, the substrate specificity of these enzymes is low. We have recently shown however, that isolated fibrillin microfibrils are susceptible to direct degradation by physiologically attainable doses of UV-B radiation and that elastic fibre proteins as a group are highly enriched in UV-absorbing amino acid residues. Functionally, elastic fibre remodeling events may adversely impact on: the mechanical properties of tissues, the recruitment and activation of immune cells, the expression of matrix metalloproteinases and cytokine signaling (by perturbing fibrillin microfibril sequestration of TGFβ). Finally, newly developed topical interventions appear to be capable of regenerating elements of the elastic fibre system in ageing skin, whilst systemic treatments may potentially prevent the pathological tissue remodeling events which occur in response to elastic fibre degradation.

  9. Elevated cysteine-rich protein 61 (CCN1) promotes skin aging via upregulation of IL-1β in chronically sun-exposed human skin.

    PubMed

    Qin, Zhaoping; Okubo, Toru; Voorhees, John J; Fisher, Gary J; Quan, Taihao

    2014-02-01

    Chronic exposure of human skin to solar ultraviolet (UV) irradiation causes premature skin aging, which is characterized by reduced type I collagen production and increased fragmentation of the dermal collagenous extracellular matrix. This imbalance of collagen homeostasis is mediated, in part, by elevated expression of the matricellular protein cysteine-rich protein 61 (CCN1), in dermal fibroblasts, the primary collagen producing cell type in human skin. Here, we report that the actions of CCN1 are mediated by induction of interleukin 1β (IL-1β). CCN1 and IL-1β are strikingly induced by acute UV irradiation, and constitutively elevated in sun-exposed prematurely aged human skin. Elevated CCN1 rapidly induces IL-1β, inhibits type I collagen production, and upregulates matrix metalloproteinase-1, which degrades collagen fibrils. Blockade of IL-1β actions by IL-1 receptor antagonist largely prevents the deleterious effects of CCN1 on collagen homeostasis. Furthermore, knockdown of CCN1 significantly reduces induction of IL-1β by UV irradiation, and thereby partially prevents collagen loss. These data demonstrate that elevated CCN1promotes inflammaging and collagen loss via induction of IL-1β and thereby contributes to the pathophysiology of premature aging in chronically sun-exposed human skin.

  10. Recovery of Aging-Related Size Increase of Skin Epithelial Cells: In vivo Mouse and In vitro Human Study

    PubMed Central

    Sokolov, Igor; Guz, Natali V.; Iyer, Swaminathan; Hewitt, Amy; Sokolov, Nina A.; Erlichman, Joseph S.; Woodworth, Craig D.

    2015-01-01

    The size increase of skin epithelial cells during aging is well-known. Here we demonstrate that treatment of aging cells with cytochalasin B substantially decreases cell size. This decrease was demonstrated on a mouse model and on human skin cells in vitro. Six nude mice were treated by topical application of cytochalasin B on skin of the dorsal left midsection for 140 days (the right side served as control for placebo treatment). An average decrease in cell size of 56±16% resulted. A reduction of cell size was also observed on primary human skin epithelial cells of different in vitro age (passages from 1 to 8). A cell strain obtained from a pool of 6 human subjects was treated with cytochalasin B in vitro for 12 hours. We observed a decrease in cell size that became statistically significant and reached 20–40% for cells of older passage (6–8 passages) whereas no substantial change was observed for younger cells. These results may be important for understanding the aging processes, and for cosmetic treatment of aging skin. PMID:25807526

  11. Age-dependent variation in cytokines, chemokines, and biologic analytes rinsed from the surface of healthy human skin

    PubMed Central

    Kinn, Patrick M.; Holdren, Grant O.; Westermeyer, Brittney A.; Abuissa, Mousa; Fischer, Carol L.; Fairley, Janet A.; Brogden, Kim A.; Brogden, Nicole K.

    2015-01-01

    In the skin, aging is associated with overall epidermal thinning, decreased barrier function, and gradual deterioration of the epidermal immune response. However, the presence and role of cytokines, chemokines, and biologic analytes (CCBAs) in immunosenescence are not known. Here we identified age-related changes in skin properties and CCBAs from stratum corneum of healthy human subjects, providing a means to utilize CCBAs as benchmarks for aging skin health. Transepidermal water loss and a(*) (skin redness) decreased in an age-dependent manner, and were significantly lower (p < 0.05) in Groups 2 (56.6 ± 4.6 years) and 3 (72.9 ± 3.0 years) vs. Group 1 (24.3 ± 2.8 years). In skin wash fluid, 48 CCBAs were detected; seven were significantly lower (p < 0.05) in Groups 2 and 3: EGF, FGF-2, IFNα2, IL-1RA, HSA, keratin-6, and involucrin; cortisol was significantly higher (p < 0.05) in Groups 2 and 3. Our results correspond with the pro-inflammatory shift that occurs with immunosenescence and also provides basis for understanding the inflammatory changes in normal aging skin. PMID:26035055

  12. Continuous irradiation with a 633-nm light-emitting diode exerts an anti-aging effect on human skin cells.

    PubMed

    Kim, Hak Sun; Park, Won Sang; Baek, Jong-In; Lee, Bo-Sub; Yoo, Dae Sung; Park, Si Jun

    2015-02-01

    Accumulating evidence has indicated that the light source emitted from light‑emitting diode (LED) has a potential anti-aging effect on human skin. Studies using single and interval LED irradiation have documented such effects; however, to the best of our knowledge, the anti-aging effects of continuous LED irradiation have not yet been investigated. In the present study, we demonstrated that continuous irradiation with a 633±3-nm LED exerted anti-aging effects in both in vitro and ex vivo experiments. More specifically, irradiation with a 633-nm LED for 2 days increased the synthesis of type 1 procollagen and decreased the expression of matrix metalloproteinase (MMP)1 and MMP2 in skin fibroblasts. In addition, irradiation with a 633-nm LED decreased the expression levels of inflammatory genes, such has cyclooxygenase-2 (COX-2), and interleukin-1-α (IL-1α) in keratinocytes. Furthermore, a 14-day LED irradiation moderately increased keratinocyte proliferation. Using human skin explants, we confirmed the safety of this 633-nm LED irradiation, which resulted in unaltered morphology and allergy-free potential in human tissue. Overall, these data provide insight into the anti-aging effects of continuous LED irradiation on human skin.

  13. Influence of age and sun exposure on the biophysical properties of the human skin: an in vivo study.

    PubMed

    Adhoute, H; de Rigal, J; Marchand, J P; Privat, Y; Leveque, J L

    1992-06-01

    The physical properties of the skin were measured by using noninvasive methods on 72 people displaying various levels of solar elastosis on the neck. The physical parameters measured were the skin extensibility, the elastic recovery, the skin colour, the skin thickness and the electrical conductance. The correlation between the above parameters, the clinical grades of elastosis and the chronological age of each subject were studied using two different statistical approaches. They both showed that elastotic skin is less elastic, dryer, darker, more erythematous and less yellowish than the nonexposed skin. The similarities and differences between the properties of elastotic skin and purely chronologically aged skin are discussed.

  14. Neuromodulators for Aging Skin

    MedlinePlus

    ... Stretch Marks Sun-damaged Skin Unwanted Hair Unwanted Tattoos Varicose Veins Vitiligo Wrinkles Treatments and Procedures Ambulatory ... Stretch Marks Sun-damaged Skin Unwanted Hair Unwanted Tattoos Varicose Veins Vitiligo Wrinkles Treatments and Procedures Ambulatory ...

  15. Characteristics of the Aging Skin

    PubMed Central

    Farage, Miranda A.; Miller, Kenneth W.; Elsner, Peter; Maibach, Howard I.

    2013-01-01

    Significance Although most researches into the changes in skin with age focus on the unwelcome aesthetic aspects of the aging skin, skin deterioration with age is more than a merely cosmetic problem. Although mortality from skin disease is primarily restricted to melanoma, dermatological disorders are ubiquitous in older people with a significant impact on quality of life. The structural and functional deterioration of the skin that occurs with age has numerous clinical presentations, ranging from benign but potentially excruciating disorders like pruritus to the more threatening carcinomas and melanomas. Recent Advances The degenerative changes that occur in the aging skin are increasingly understood at both the molecular and cellular level, facilitating a deeper understanding of the structural and functional deterioration that these changes produce. Critical Issues A loss of both function and structural stability in skin proceeds unavoidably as individuals age, which is the result of both intrinsic and extrinsic processes, which contribute simultaneously to a progressive loss of skin integrity. Intrinsic aging proceeds at a genetically determined pace, primarily caused by the buildup of damaging products of cellular metabolism as well as an increasing biological aging of the cells. Estrogen levels strongly influence skin integrity in women as well; falling levels in midlife, therefore, produce premature aging as compared with similarly aged men. Extrinsic insults from the environment add to the dermatological signs of aging. Future Directions A deeper understanding of the physiological basis of skin aging will facilitate progress in the treatment of the unwelcome sequelae of aging skin, both cosmetic and pathogenic. PMID:24527317

  16. Reflex vasoconstriction in aged human skin increasingly relies on Rho kinase-dependent mechanisms during whole body cooling

    PubMed Central

    Jennings, John D.; Holowatz, Lacy A.; Kenney, W. Larry

    2009-01-01

    Primary human aging may be associated with augmented Rho kinase (ROCK)-mediated contraction of vascular smooth muscle and ROCK-mediated inhibition of nitric oxide synthase (NOS). We hypothesized that the contribution of ROCK to reflex vasoconstriction (VC) is greater in aged skin. Cutaneous VC was elicited by 1) whole body cooling [mean skin temperature (Tsk) = 30.5°C] and 2) local norepinephrine (NE) infusion (1 × 10−6 M). Four microdialysis fibers were placed in the forearm skin of eight young (Y) and eight older (O) subjects for infusion of 1) Ringer solution (control), 2) 3 mM fasudil (ROCK inhibition), 3) 20 mM NG-nitro-l-arginine methyl ester (NOS inhibition), and 4) both ROCK + NOS inhibitors. Red cell flux was measured by laser-Doppler flowmetry over each site. Cutaneous vascular conductance (CVC) was calculated as flux/mean arterial pressure and normalized to baseline CVC (%ΔCVCbaseline). VC was reduced at the control site in O during cooling (Y, −34 ± 3; and O, −18 ± 3%ΔCVCbaseline; P < 0.001) and NE infusion (Y, −53 ± 4, and O, −41 ± 9%ΔCVCbaseline; P = 0.006). Fasudil attenuated VC in both age groups during mild cooling; however, this reduction remained only in O but not in Y skin during moderate cooling (Y, −30 ± 5; and O, −7 ± 1%ΔCVCbaseline; P = 0.016) and was not altered by NOS inhibition. Fasudil blunted NE-mediated VC in both age groups (Y, −23 ± 4; and O, −7 ± 3%ΔCVCbaseline; P < 0.01). Cumulatively, these data indicate that reflex VC is more reliant on ROCK in aged skin such that approximately half of the total VC response to whole body cooling is ROCK dependent. PMID:19717729

  17. Reflex vasoconstriction in aged human skin increasingly relies on Rho kinase-dependent mechanisms during whole body cooling.

    PubMed

    Lang, James A; Jennings, John D; Holowatz, Lacy A; Kenney, W Larry

    2009-11-01

    Primary human aging may be associated with augmented Rho kinase (ROCK)-mediated contraction of vascular smooth muscle and ROCK-mediated inhibition of nitric oxide synthase (NOS). We hypothesized that the contribution of ROCK to reflex vasoconstriction (VC) is greater in aged skin. Cutaneous VC was elicited by 1) whole body cooling [mean skin temperature (T(sk)) = 30.5 degrees C] and 2) local norepinephrine (NE) infusion (1 x 10(-6) M). Four microdialysis fibers were placed in the forearm skin of eight young (Y) and eight older (O) subjects for infusion of 1) Ringer solution (control), 2) 3 mM fasudil (ROCK inhibition), 3) 20 mM N(G)-nitro-l-arginine methyl ester (NOS inhibition), and 4) both ROCK + NOS inhibitors. Red cell flux was measured by laser-Doppler flowmetry over each site. Cutaneous vascular conductance (CVC) was calculated as flux/mean arterial pressure and normalized to baseline CVC (%DeltaCVC(baseline)). VC was reduced at the control site in O during cooling (Y, -34 + or - 3; and O, -18 + or - 3%DeltaCVC(baseline); P < 0.001) and NE infusion (Y, -53 + or - 4, and O, -41 + or - 9%DeltaCVC(baseline); P = 0.006). Fasudil attenuated VC in both age groups during mild cooling; however, this reduction remained only in O but not in Y skin during moderate cooling (Y, -30 + or - 5; and O, -7 + or - 1%DeltaCVC(baseline); P = 0.016) and was not altered by NOS inhibition. Fasudil blunted NE-mediated VC in both age groups (Y, -23 + or - 4; and O, -7 + or - 3%DeltaCVC(baseline); P < 0.01). Cumulatively, these data indicate that reflex VC is more reliant on ROCK in aged skin such that approximately half of the total VC response to whole body cooling is ROCK dependent.

  18. Endothelial nitric oxide synthase mediates cutaneous vasodilation during local heating and is attenuated in middle-aged human skin.

    PubMed

    Bruning, Rebecca S; Santhanam, Lakshmi; Stanhewicz, Anna E; Smith, Caroline J; Berkowitz, Dan E; Kenney, W Larry; Holowatz, Lacy A

    2012-06-01

    Local skin heating is used to assess microvascular function in clinical populations because NO is required for full expression of the response; however, controversy exists as to the precise NO synthase (NOS) isoform producing NO. Human aging is associated with attenuated cutaneous vasodilation but little is known about the middle aged, an age cohort used for comparison with clinical populations. We hypothesized that endothelial NOS (eNOS) is the primary isoform mediating NO production during local heating, and eNOS-dependent vasodilation would be reduced in middle-aged skin. Vasodilation was induced by local heating (42°C) and during acetylcholine dose-response (ACh-DR: 0.01, 0.1, 1.0, 5.0, 10.0, 50.0, 100.0 mmol/l) protocols. Four microdialysis fibers were placed in the skin of 24 men and women; age cohorts were 12 middle-aged (53 ± 1 yr) and 12 young (23 ± 1 yr). Sites served as control, nonselective NOS inhibited [N(G)-nitro-l-arginine methyl ester (l-NAME)], inducible NOS (iNOS) inhibited (1400W), and neuronal NOS (nNOS) inhibited (N(ω)-propyl-l-arginine). After full expression of the local heating response, l-NAME was perfused at all sites. Cutaneous vascular conductance was measured and normalized to maximum (%CVC(max): Nitropress). l-NAME reduced %CVCmax at baseline, all phases of the local heating response, and at all ACh concentrations compared with all other sites. iNOS inhibition reduced the initial peak (53 ± 2 vs. 60 ± 2%CVC(max); P < 0.001); however, there were no other differences between control, nNOS-, and iNOS-inhibited sites during the phases of local heating or ACh-DR. When age cohorts were compared, NO-dependent vasodilation during local heating (52 ± 6 vs. 68 ± 4%CVC(max); P = 0.013) and ACh perfusion (50 mmol/l: 83 ± 3 vs. 93 ± 2%CVC(max); 100 mmol/l: 83 ± 4 vs. 92 ± 3%CVC(max); both P = 0.03) were reduced in middle-aged skin. There were no differences in NOS isoform expression obtained from skin biopsy samples between groups (all

  19. Effects of ageing and fitness on skin-microvessel vasodilator function in humans.

    PubMed

    Tew, Garry A; Klonizakis, Markos; Saxton, John M

    2010-05-01

    The impact of cardiopulmonary fitness (VO(2max)) on the age-related decline in skin-microvessel vasodilator function has not been fully established and the inter-relationships among different measures of microvascular vasodilator function are unknown. We used laser Doppler flowmetry to assess relative changes in forearm skin blood flow to various stimuli in three groups of adults: young (n = 15; 27 +/- 2 years), older sedentary (n = 14; 65 +/- 6 years) and older fit (n = 15; 61 +/- 5 years). Local-heating induced and post-occlusive hyperaemia responses were higher in the young and older fit groups compared to the older sedentary group (P < 0.05) and were moderately correlated with VO(2max) in the pooled cohort of older adults (r = 0.49-0.58; P < 0.05). Peak hyperaemia responses to acetylcholine and sodium nitroprusside were higher in young compared to older sedentary adults (P < 0.05) and were not associated with VO(2max) in older adults (P > 0.05). Associations among different measures of microvascular vasodilator function were generally moderate at best. In summary, the local heating and reactive hyperaemia data indicate that the age-related decline in skin-microvessel vasodilator function can be ameliorated through regular aerobic exercise training. As this is not supported by the iontophoresis data, we recommend that, when assessing microvascular function, the use of a single physiological or pharmacological stimulation coupled to laser Doppler flowmetry should be avoided. Finally, the moderate correlations between outcomes probably reflect the distinct mediators that are responsible for the vasodilator response to each test.

  20. Aging Differences in Ethnic Skin

    PubMed Central

    Buainain De Castro Maymone, Mayra; Kundu, Roopal V.

    2016-01-01

    Aging is an inevitable and complex process that can be described clinically as features of wrinkles, sunspots, uneven skin color, and sagging skin. These cutaneous effects are influenced by both intrinsic and extrinsic factors and often are varied based on ethnic origin given underlying structural and functional differences. The authors sought to provide updated information on facets of aging and how it relates to ethnic variation given innate differences in skin structure and function. Publications describing structural and functional principles of ethnic and aging skin were primarily found through a PubMed literature search and supplemented with a review of textbook chapters. The most common signs of skin aging despite skin type are dark spots, loss of elasticity, loss of volume, and rhytides. Skin of color has many characteristics that make its aging process unique. Those of Asian, Hispanic, and African American descent have distinct facial structures. Differences in the concentration of epidermal melanin makes darkly pigmented persons more vulnerable to dyspigmentation, while a thicker and more compact dermis makes facial lines less noticeable. Ethnic skin comprises a large portion of the world population. Therefore, it is important to understand the unique structural and functional differences among ethnicities to adequately treat the signs of aging. PMID:26962390

  1. Aging changes in skin

    MedlinePlus

    ... sun exposure with areas that are protected from sunlight. Natural pigments seem to provide some protection against ... Exposures to industrial and household chemicals Indoor heating Sunlight can cause: Loss of elasticity (elastosis) Noncancerous skin ...

  2. Oxygen tension changes the rate of migration of human skin keratinocytes in an age-related manner.

    PubMed

    Ross, Caitlin; Alston, Myrissa; Bickenbach, Jackie R; Aykin-Burns, Nukhet

    2011-01-01

    Migration of keratinocytes to re-epithelialize wounds is a key step in dermal wound healing. In aged human skin, wound healing rates decrease and cellular damage by reactive oxygen species (ROS) accumulates. The relationship between age, ROS and human skin keratinocyte migration is not clearly understood. In this study, 4% and 21% oxygen tensions were used to modify levels of ROS produced by metabolism to model low and high oxidative stress conditions. When migration of keratinocytes from young and old primary skin was compared using an in vitro scratch assay, old keratinocytes migrated faster in high oxygen tension than did young keratinocytes, whereas young keratinocytes migrated faster in low oxygen tension. Although all young and old cells at the scratch margins showed intense increases in dihydroethidium oxidation immediately after scratching, the old keratinocytes grown at 21% oxygen demonstrated a greater decrease in the DHE oxidation following scratching and migrated the fastest. These results show that old and young keratinocytes respond to oxygen tension differently and support the hypothesis that keratinocyte migration is affected by the capacity to remove ROS.

  3. Archaea on Human Skin

    PubMed Central

    Probst, Alexander J.; Auerbach, Anna K.; Moissl-Eichinger, Christine

    2013-01-01

    The recent era of exploring the human microbiome has provided valuable information on microbial inhabitants, beneficials and pathogens. Screening efforts based on DNA sequencing identified thousands of bacterial lineages associated with human skin but provided only incomplete and crude information on Archaea. Here, we report for the first time the quantification and visualization of Archaea from human skin. Based on 16 S rRNA gene copies Archaea comprised up to 4.2% of the prokaryotic skin microbiome. Most of the gene signatures analyzed belonged to the Thaumarchaeota, a group of Archaea we also found in hospitals and clean room facilities. The metabolic potential for ammonia oxidation of the skin-associated Archaea was supported by the successful detection of thaumarchaeal amoA genes in human skin samples. However, the activity and possible interaction with human epithelial cells of these associated Archaea remains an open question. Nevertheless, in this study we provide evidence that Archaea are part of the human skin microbiome and discuss their potential for ammonia turnover on human skin. PMID:23776475

  4. Archaea on human skin.

    PubMed

    Probst, Alexander J; Auerbach, Anna K; Moissl-Eichinger, Christine

    2013-01-01

    The recent era of exploring the human microbiome has provided valuable information on microbial inhabitants, beneficials and pathogens. Screening efforts based on DNA sequencing identified thousands of bacterial lineages associated with human skin but provided only incomplete and crude information on Archaea. Here, we report for the first time the quantification and visualization of Archaea from human skin. Based on 16 S rRNA gene copies Archaea comprised up to 4.2% of the prokaryotic skin microbiome. Most of the gene signatures analyzed belonged to the Thaumarchaeota, a group of Archaea we also found in hospitals and clean room facilities. The metabolic potential for ammonia oxidation of the skin-associated Archaea was supported by the successful detection of thaumarchaeal amoA genes in human skin samples. However, the activity and possible interaction with human epithelial cells of these associated Archaea remains an open question. Nevertheless, in this study we provide evidence that Archaea are part of the human skin microbiome and discuss their potential for ammonia turnover on human skin.

  5. Mechanisms of acetylcholine-mediated vasodilatation in young and aged human skin

    PubMed Central

    Holowatz, Lacy A; Thompson, Caitlin S; Minson, Christopher T; Kenney, W Larry

    2005-01-01

    Thermoregulatory cutaneous vasodilatation (VD) is attenuated in aged skin. While acetylcholine (ACh) plays a role in thermally mediated VD, the precise mechanisms through which ACh-mediated VD acts and whether those downstream mechanisms change with ageing are unclear. We tested the hypotheses that both nitric oxide (NO)- and prostanoid-mediated pathways contribute to exogenous ACh-mediated VD, and that both are attenuated with advanced age. Twelve young (Y: 23 ± 1 years) and 10 older (O: 69 ± 1 years) subjects underwent infusions of 137.5 μm ACh at four intradermal microdialysis sites: control (C, Ringer solution), NO synthase inhibited (NOS-I, 10 mml-NAME), cyclooxygenase inhibited (COX-I, 10 mm ketorolac) and NOS-I + COX-I. Red blood cell flux was monitored using laser-Doppler flowmetry, and cutaneous vascular conductance (CVC) was calculated (laser-Doppler flux/mean arterial pressure) and normalized to maximal CVC (%CVCmax) (28 mm sodium nitroprusside + local heating to 43°C). Baseline %CVCmax was increased in the O at COX-I sites (COX-I 16 ± 1, NOS-I + COX-I 16 ± 2 versus C 10 ± 1%CVCmax; P < 0.001) but not in the young, suggesting an age-related shift toward COX vasoconstrictors contributing to basal cutaneous vasomotor tone. There was no difference in peak %CVCmax during ACh infusion between age groups, and the response was unchanged by NOS-I (O: NOS-I 35 ± 5 versus C 38 ± 5%CVCmax; P = 0.84) (Y: NOS-I 41 ± 4 versus C 39 ± 4%CVCmax; P = 0.67). COX-I and NOS-I + COX-I attenuated the peak CVC response to ACh in both groups (COX-I O: 29 ± 3, Y: 22 ± 2%CVCmaxversus C; P < 0.001 both groups; NOS-I + COX-I O: 32 ± 3 versus Y: 29 ± 2%CVCmax; versus C; P < 0.001 both groups). ACh mediates cutaneous VD through prostanoid and non-NO-, non-prostanoid-dependent pathways. Further, older subjects have a diminished prostanoid contribution to ACh-mediated VD. PMID:15661816

  6. Gastrodia elata Blume Extract Modulates Antioxidant Activity and Ultraviolet A-Irradiated Skin Aging in Human Dermal Fibroblast Cells.

    PubMed

    Song, Eunju; Chung, Haeyon; Shim, Eugene; Jeong, Jung-Ky; Han, Bok-Kyung; Choi, Hyuk-Joon; Hwang, Jinah

    2016-11-01

    Gastrodia elata Blume (GEB), a traditional herbal medicine, has been used to treat a wide range of neurological disorders (e.g., paralysis and stroke) and skin problems (e.g., atopic dermatitis and eczema) in oriental medicine. This study was designed to investigate the antioxidant ability of GEB and its antiaging effect on human dermal fibroblast cells (HDF). The total phenolic and flavonoid contents of GEB were 21.8 and 0.43 mg/g dry weight (DW), respectively. The ergothioneine content of GEB was 0.41 mg/mL DW. The DPPH and ABTS radical scavenging activities of GEB at 5 and 10 mg/mL approximately ranged between 31% and 44%. The superoxide dismutase activity of GEB at 10 and 25 mg/mL was 57% and 76%, respectively. GEB increased procollagen type 1 (PC1) production and inhibited matrix metalloproteinase-1 (MMP-1) production and elastase-1 activity in UVA-irradiated HDF. PC1 messenger RNA (mRNA) levels decreased upon UVA irradiation, but recovered in response to high doses of GEB in HDF. On the contrary, GEB significantly decreased MMP-1 and elastase-1 mRNA levels, which were markedly induced in UVA-irradiated HDF. Collectively, these results suggest that GEB has sufficient antioxidant ability to prevent the signs of skin aging in UVA-irradiated human skin cells, suggesting its potential as a natural antiaging product.

  7. Expression of catalytically active Matrix Metalloproteinase-1 in dermal fibroblasts induces collagen fragmentation and functional alterations that resemble aged human skin

    PubMed Central

    Xia, Wei; Hammerberg, Craig; Li, Yong; He, Tianyuan; Quan, Taihao; Voorhees, John J; Fisher, Gary J

    2013-01-01

    Summary Increased expression of matrix metalloproteinase-1 (MMP-1) and reduced production of type I collagen by dermal fibroblasts are prominent features of aged human skin. We have proposed that MMP-1-mediated collagen fibril fragmentation is a key driver of age-related decline of skin function. To investigate this hypothesis, we constructed, characterized, and expressed constitutively active MMP-1 mutant (MMP-1 V94G) in adult human skin in organ culture and fibroblasts in three dimensional collagen lattice cultures. Expression of MMP-1 V94G in young skin in organ culture caused fragmentation and ultrastructural alterations of collagen fibrils similar to those observed in aged human skin in vivo. Expression of MMP-1 V94G in dermal fibroblasts cultured in three-dimensional collagen lattices caused substantial collagen fragmentation, which was markedly reduced by MMP-1 siRNA-mediated knockdown or MMP inhibitor MMI270. Importantly, fibroblasts cultured in MMP-1 V94G-fragmented collagen lattices displayed many alterations observed in fibroblasts in aged human skin, including reduced cytoplasmic area, disassembled actin cytoskeleton, impaired TGF-β pathway, and reduced collagen production. These results support the concept that MMP-1-mediated fragmentation of dermal collagen fibrils alters the morphology and function of dermal fibroblasts, and provide a foundation for understanding specific mechanisms that link collagen fibril fragmentation to age-related decline of fibroblast function. PMID:23601157

  8. Chromophores in human skin

    NASA Astrophysics Data System (ADS)

    Young, Antony R.

    1997-05-01

    Human skin, especially the epidermis, contains several major solar ultraviolet-radiation- (UVR-) absorbing endogenous chromophores including DNA, urocanic acid, amino acids, melanins and their precursors and metabolites. The lack of solubility of melanins prevents their absorption spectra being defined by routine techniques. Indirect spectroscopic methods show that their spectral properties depend on the stimulus for melanogenesis. The photochemical consequences of UVR absorption by some epidermal chromophores are relatively well understood whereas we lack a detailed understanding of the consequent photobiological and clinical responses. Skin action spectroscopy is not a reliable way of relating a photobiological outcome to a specific chromophore but is important for UVR hazard assessment. Exogenous chromophores may be administered to the skin in combination with UVR exposure for therapeutic benefit, or as sunscreens for the prevention of sunburn and possibly skin cancer.

  9. [Skin ageing and its prevention].

    PubMed

    Passeron, Thierry; Ortonne, Jean-Paul

    2003-09-27

    INTRINSIC AND EXTRINSIC FACTORS: Skin ageing is due to the conjunction of intrinsic (chronological ageing) and extrinsic factors (fundamentally photo-ageing). The physiopathological mechanisms of intrinsic ageing rejoin those of the ageing of all the other organs. Among the intrinsic causes, tobacco and above all ultra-violet radiation, UVB and also UVA, play a preponderant role. Photo-ageing is secondary to complex mechanisms that are increasingly known. The UVB directly interact with the DNA of the cutaneous cells. The deleterious effects of UVA are principally due to the formation of free radical oxygen, which result in an alteration in the nuclear and also mitochondrial DNA, but also an activation of the enzymes, metalloproteinase, capable of damaging the extra-cellular matrix. DELETERIOUS CONSEQUENCES: The phenomena of ageing provoke the decline in defence, healing and perception mechanisms and in the thermoregulation of the skin tissue. There are numerous and often unsightly clinical manifestations. Photo-ageing can be considered as a marker of risk of photo-carcinogenesis requiring increased clinical surveillance. PREVENTIVE AND CURATIVE MEASURES: The prevention of skin ageing must be based on the use of sunscreens protecting against both UVB and UVA, but, in order for them to be effective, they require a change in general life style. There are many efficient therapeutic means, but the possible side effects must be known and explained to the patient. Retinoids, in view of their innocuousness and efficacy not only in prevention but also treatment of skin ageing, should be considered as a therapeutic option of choice.

  10. Local tetrahydrobiopterin administration augments reflex cutaneous vasodilation through nitric oxide-dependent mechanisms in aged human skin.

    PubMed

    Stanhewicz, Anna E; Bruning, Rebecca S; Smith, Caroline J; Kenney, W Larry; Holowatz, Lacy A

    2012-03-01

    (max), P < 0.001) but not the young (BH(4): 23 ± 4%CVC(max) vs. control: 21 ± 4%CVC(max), P = 0.718) subject group. Together these data suggest that reduced BH(4) contributes to attenuated vasodilation in aged human skin and that BH(4) NOS coupling mechanisms may be a potential therapeutic target for increasing skin blood flow during hyperthermia in older humans.

  11. Factors of skin ageing share common mechanisms.

    PubMed

    Giacomoni, P U; Rein, G

    2001-01-01

    Ageing has been defined as the accumulation of molecular modifications which manifest as macroscopic clinical changes. Human skin, unique among mammalians insofar as it is deprived of fur, is particularly sensitive to environmental stress. Major environmental factors have been recognized to induce modifications of the morphological and biophysical properties of the skin. Metabolites from ingested or inhaled substances do affect skin, which is also sensitive to endogenous hormone levels. Factors as diverse as ultraviolet radiation, atmospheric pollution, wounds, infections, traumatisms, anoxya, cigarette smoke, and hormonal status have a role in increasing the rate of accumulation of molecular modifications and have thus been termed 'factors of ageing'. All these factors share as a common feature, the capability to directly or indirectly induce one of the steps of the micro-inflammatory cycle, which includes the expression of ICAM-1 in endothelial cells. This triggers a process leading to the accumulation of damages in the skin resulting in skin ageing since ICAM-1 expression provokes recruitment and diapedesis of circulating immune cells, which digest the extracellular matrix (ECM) by secreting collagenases, myeloperoxidases and reactive oxygen species. The activation of these lytic processes provokes random damage to resident cells, which in turn secrete prostaglandines and leukotrienes. These signaling molecules induce the degranulation of resident mast cells which release the autacoid histamine and the cytokine TNF-alpha thus activating endothelial cells lining adjacent capillaries which release P-selectin and synthesize ICAM-1. This closes a self-maintained micro-inflammatory cycle, which results in the accumulation of ECM damage, i.e. skin aging. In this paper we review the evidence that two factors able to induce macroscopical and molecular modifications in the skin, protein glycation and stretch, activate the micro-inflammatory cycle. We further present

  12. Ultraviolet radiation exposure accelerates the accumulation of the aging-dependent T414G mitochondrial DNA mutation in human skin.

    PubMed

    Birket, Matthew J; Birch-Machin, Mark A

    2007-08-01

    The accumulation of mitochondrial DNA (mtDNA) mutations has been proposed as an underlying cause of the aging process. Such mutations are thought to be generated principally through mechanisms involving oxidative stress. Skin is frequently exposed to a potent mutagen in the form of ultraviolet (UV) radiation and mtDNA deletion mutations have previously been shown to accumulate with photoaging. Here we report that the age-related T414G point mutation originally identified in skin fibroblasts from donors over 65 years also accumulates with age in skin tissue. Moreover, there is a significantly greater incidence of this mutation in skin from sun-exposed sites (chi(2)= 6.8, P < 0.01). Identification and quantification of the T414G mutation in dermal skin tissue from 108 donors ranging from 8 to 97 years demonstrated both increased occurrence with photoaging as well as an increase in the proportion of molecules affected. In addition, we have discovered frequent genetic linkage between a common photoaging-associated mtDNA deletion and the T414G mutation. This linkage indicates that mtDNA mutations such as these are unlikely to be distributed equally across the mtDNA population within the skin tissue, increasing their likelihood of exerting focal effects at the cellular level. Taken together, these data significantly contribute to our understanding of the DNA damaging effects of UV exposure and how resultant mutations may ultimately contribute towards premature aging.

  13. Sexual hormones in human skin.

    PubMed

    Zouboulis, C C; Chen, W-C; Thornton, M J; Qin, K; Rosenfield, R

    2007-02-01

    The skin locally synthesizes significant amounts of sexual hormones with intracrine or paracrine actions. The local level of each sexual steroid depends upon the expression of each of the androgen- and estrogen-synthesizing enzymes in each cell type, with sebaceous glands and sweat glands being the major contributors. Sebocytes express very little of the key enzyme, cytochrome P450c17, necessary for synthesis of the androgenic prohormones dehydroepiandrosterone and androstenedione, however, these prohormones can be converted by sebocytes and sweat glands, and probably also by dermal papilla cells, into more potent androgens like testosterone and dihydrotestosterone. Five major enzymes are involved in the activation and deactivation of androgens in skin. Androgens affect several functions of human skin, such as sebaceous gland growth and differentiation, hair growth, epidermal barrier homeostasis and wound healing. Their effects are mediated by binding to the nuclear androgen receptor. Changes of isoenzyme and/or androgen receptor levels may have important implications in the development of hyperandrogenism and the associated skin diseases such as acne, seborrhoea, hirsutism and androgenetic alopecia. On the other hand, estrogens have been implicated in skin aging, pigmentation, hair growth, sebum production and skin cancer. Estrogens exert their actions through intracellular receptors or via cell surface receptors, which activate specific second messenger signaling pathways. Recent studies suggest specific site-related distribution of ERalpha and ERbeta in human skin. In contrast, progestins play no role in the pathogenesis of skin disorders. However, they play a major role in the treatment of hirsutism and acne vulgaris, where they are prescribed as components of estrogen-progestin combination pills and as anti-androgens. These combinations enhance gonadotropin suppression of ovarian androgen production. Estrogen-progestin treatment can reduce the need for shaving

  14. In vivo confocal Raman microspectroscopy of the human skin: highlighting of spectral markers associated to aging via a research of correlation between Raman and biometric mechanical measurements.

    PubMed

    Eklouh-Molinier, Christophe; Gaydou, Vincent; Froigneux, Emmanuel; Barlier, Pascale; Couturaud, Virginie; Manfait, Michel; Piot, Olivier

    2015-11-01

    Skin plays a protective role against the loss of water and external aggression, including mechanical stresses. These crucial functions are ensured by different cutaneous layers, particularly the stratum corneum (SC). During aging, the human skin reveals some apparent modifications of functionalities such as a loss of elasticity. Our investigations aimed at demonstrating that Raman microspectroscopy, as a label-free technique with a high molecular specificity, is efficient to assess in vivo the molecular composition of the skin and the alterations underwent during aging. Our approach was based on a search for correlation between Raman data collected on healthy female volunteers of different ages (from 21 to 70 years old) by means of a remote confocal Raman and skin firmness measurements used as a reference method. Raman and biometric data were then submitted to a partial least square (PLS)-based data processing. Our experiments demonstrated the potential of Raman microspectroscopy to provide an objective in vivo assessment of the skin "biological age" that can be very different from the "chronological age" of the person. In addition, Raman features sensitive to the elasticity and the fatigability of the SC were highlighted. Thereafter, calibration transfer functions were constructed to show the possibility to compare the results obtained during two distinct measurement campaigns conducted with two Raman probes of the same conception. This approach could lead to several interesting prospects, in particular by objectifying the effects of dermocosmetic products on the superficial layers of the skin and by accessing some underlying molecular mechanisms.

  15. Age-related crosslink in skin collagen

    SciTech Connect

    Yamauchi, M.; Mechanic, G.

    1986-05-01

    A stable crosslinking amino acid was isolated from mature bovine skin collagen and its structure was identified as histidinohydroxylysinonorleucine (HHL) using fast atom bombardment mass spectrometry and /sup 1/H, /sup 13/C-NMR. This newly identified crosslink has a linkage between C-2 histidine and C-6 of lysine in the latter's portion of hydroxylysinonorleucine. Quantitative studies using various aged samples of cow and human skin collagen indicated that this acid-heat stable nonreducible compound was the major age-related crosslink. In case of cow skin collagen, for example, during early embryonic development (3 and 5 month old embryos) the content of HHL stayed less than 0.01 residue/mole of collagen, however from the middle of gestation period (7 month old embryo) through the maturation stage it showed rapid increase with age and reached approximately 0.5 residues/mole of collagen in the 3 year old animal. Small increments (up to 0.65 res/mole of collagen) were observed in the 9 year old cow. The amounts of the crosslink unlike pyridinoline do not decrease with aging. Similar patterns were observed in human skin collagen.

  16. Curcumin induces stress response and hormetically modulates wound healing ability of human skin fibroblasts undergoing ageing in vitro.

    PubMed

    Demirovic, Dino; Rattan, Suresh I S

    2011-10-01

    Wound healing becomes impaired in several diseases and during ageing. A commonly used model for the study of wound healing is a scratched monolayer of cells in vitro, which is convenient for the analysis of the cellular and molecular changes occurring during the two phases of wound healing, namely cell migration and cell proliferation. Cell migration, which is the primary event to occur during initial wound healing, is inversely dependent on the number of focal adhesions (FA) that attach cells to the extracellular matrix. Here we report that the number of FA, measured by determining the levels of FA-proteins paxillin and talin, increase with increasing population doubling level of the serially passaged normal adult skin fibroblasts, and that this increase may account for the age-related slowing down of wound healing in vitro. We also report that curcumin, a component of the widely used spice turmeric, modulates wound healing in vitro in a biphasic dose response manner, being stimulatory at low doses (between 1 and 5 μM), and inhibitory at higher doses. Furthermore, our results show that the hormetic effects of low levels of curcumin are achieved by virtue of it being a hormetin in terms of the induction of stress response pathways, including Nrf2 and HO-1 in human cells.

  17. The Influence of Age and Gender on Skin-Associated Microbial Communities in Urban and Rural Human Populations

    PubMed Central

    Ying, Shi; Zeng, Dan-Ning; Chi, Liang; Tan, Yuan; Galzote, Carlos; Cardona, Cesar; Lax, Simon; Gilbert, Jack; Quan, Zhe-Xue

    2015-01-01

    Differences in the bacterial community structure associated with 7 skin sites in 71 healthy people over five days showed significant correlations with age, gender, physical skin parameters, and whether participants lived in urban or rural locations in the same city. While body site explained the majority of the variance in bacterial community structure, the composition of the skin-associated bacterial communities were predominantly influenced by whether the participants were living in an urban or rural environment, with a significantly greater relative abundance of Trabulsiella in urban populations. Adults maintained greater overall microbial diversity than adolescents or the elderly, while the intragroup variation among the elderly and rural populations was significantly greater. Skin-associated bacterial community structure and composition could predict whether a sample came from an urban or a rural resident ~5x greater than random. PMID:26510185

  18. The Influence of Age and Gender on Skin-Associated Microbial Communities in Urban and Rural Human Populations.

    PubMed

    Ying, Shi; Zeng, Dan-Ning; Chi, Liang; Tan, Yuan; Galzote, Carlos; Cardona, Cesar; Lax, Simon; Gilbert, Jack; Quan, Zhe-Xue

    2015-01-01

    Differences in the bacterial community structure associated with 7 skin sites in 71 healthy people over five days showed significant correlations with age, gender, physical skin parameters, and whether participants lived in urban or rural locations in the same city. While body site explained the majority of the variance in bacterial community structure, the composition of the skin-associated bacterial communities were predominantly influenced by whether the participants were living in an urban or rural environment, with a significantly greater relative abundance of Trabulsiella in urban populations. Adults maintained greater overall microbial diversity than adolescents or the elderly, while the intragroup variation among the elderly and rural populations was significantly greater. Skin-associated bacterial community structure and composition could predict whether a sample came from an urban or a rural resident ~5x greater than random.

  19. The influence of age and gender on skin-associated microbial communities in urban and rural human populations

    DOE PAGES

    Ying, Shi; Zeng, Dan -Ning; Chi, Liang; ...

    2015-10-28

    Differences in the bacterial community structure associated with 7 skin sites in 71 healthy people over five days showed significant correlations with age, gender, physical skin parameters, and whether participants lived in urban or rural locations in the same city. While body site explained the majority of the variance in bacterial community structure, the composition of the skin-associated bacterial communities were predominantly influenced by whether the participants were living in an urban or rural environment, with a significantly greater relative abundance of Trabulsiella in urban populations. Adults maintained greater overall microbial diversity than adolescents or the elderly, while the intragroupmore » variation among the elderly and rural populations was significantly greater. Lastly, skin-associated bacterial community structure and composition could predict whether a sample came from an urban or a rural resident ~ 5x greater than random.« less

  20. The influence of age and gender on skin-associated microbial communities in urban and rural human populations

    SciTech Connect

    Ying, Shi; Zeng, Dan -Ning; Chi, Liang; Tan, Yuan; Galzote, Carlos; Cardona, Cesar; Lax, Simon; Gilbert, Jack; Quan, Zhe -Xue; Badger, Jonathan H.

    2015-10-28

    Differences in the bacterial community structure associated with 7 skin sites in 71 healthy people over five days showed significant correlations with age, gender, physical skin parameters, and whether participants lived in urban or rural locations in the same city. While body site explained the majority of the variance in bacterial community structure, the composition of the skin-associated bacterial communities were predominantly influenced by whether the participants were living in an urban or rural environment, with a significantly greater relative abundance of Trabulsiella in urban populations. Adults maintained greater overall microbial diversity than adolescents or the elderly, while the intragroup variation among the elderly and rural populations was significantly greater. Lastly, skin-associated bacterial community structure and composition could predict whether a sample came from an urban or a rural resident ~ 5x greater than random.

  1. [Age-dependent characteristics of the skin peripheral blood flow oscillations by nonlinear dynamics methods in humans].

    PubMed

    Tankanag, A V; Tikhonova, I V; Chemeris, N K

    2008-03-01

    Study of peripheral microhaemodynamics was carried out with laser Doppler flowmetry in healthy volunteers of different age groups. The ageing changes in the state of the skin peripheral blood flow, in the functioning of separate links and regulatory systems ofmicrovascular bed have been estimated in terms of relative entropy and fractal dimension values. The revealed significant age-dependent decrease of relative entropy values in the respiratory rhythm ranges, the neurogenic and myogenic activities yielded some evidence concerning the reduction of the microcirculation system chaotic changes within these frequency ranges during the ageing. The significant increase of fractal dimension values in the ranges of cardio-rhythm and the endothelial activity in the oldest group with the mean age of 77 years indicated that the structural complexity of the oscillations in these frequency ranges increased during ageing.

  2. Monogenic human skin disorders.

    PubMed

    Lemke, Johannes R; Kernland-Lang, Kristin; Hörtnagel, Konstanze; Itin, Peter

    2014-01-01

    Human genodermatoses represent a broad and partly confusing spectrum of countless rare diseases with confluent and overlapping phenotypes often impeding a precise diagnosis in an affected individual. High-throughput sequencing techniques have expedited the identification of novel genes and have dramatically simplified the establishment of genetic diagnoses in such heterogeneous disorders. The precise genetic diagnosis of a skin disorder is crucial for the appropriate counselling of patients and their relatives regarding the course of the disease, prognosis and recurrence risks. Understanding the underlying pathophysiology is a prerequisite to understanding the disease and developing specific, targeted or individualized therapeutic approaches. We aimed to create a comprehensive overview of human genodermatoses and their respective genetic aetiology known to date. We hope this may represent a useful tool in guiding dermatologists towards genetic diagnoses, providing patients with individual knowledge on the respective disorder and applying novel research findings to clinical practice.

  3. Skin Aging-Dependent Activation of the PI3K Signaling Pathway via Downregulation of PTEN Increases Intracellular ROS in Human Dermal Fibroblasts

    PubMed Central

    Park, Jinny; Song, Hwa-Ryung; Lee, Minok; Hong, On-Yu; Whang, Pyoung H.; Han, Myung-Kwan; Kwon, Kang-Beom

    2016-01-01

    Reactive oxygen species (ROS) play a major role in both chronological aging and photoaging. ROS induce skin aging through their damaging effect on cellular constituents. However, the origins of ROS have not been fully elucidated. We investigated that ROS generation of replicative senescent fibroblasts is generated by the modulation of phosphatidylinositol 3,4,5-triphosphate (PIP3) metabolism. Reduction of the PTEN protein, which dephosphorylates PIP3, was responsible for maintaining a high level of PIP3 in replicative cells and consequently mediated the activation of the phosphatidylinositol-3-OH kinase (PI3K)/Akt pathway. Increased ROS production was blocked by inhibition of PI3K or protein kinase C (PKC) or by NADPH oxidase activating in replicative senescent cells. These data indicate that the signal pathway to ROS generation in replicative aged skin cells can be stimulated by reduced PTEN level. Our results provide new insights into skin aging-associated modification of the PI3K/NADPH oxidase signaling pathway and its relationship with a skin aging-dependent increase of ROS in human dermal fibroblasts. PMID:28003865

  4. Transforming growth factors (TGF-alpha and TGF-beta1) in the determination of vitality and wound age: immunohistochemical study on human skin wounds.

    PubMed

    Grellner, W; Vieler, S; Madea, B

    2005-10-29

    In continuation of former investigations on proinflammatory cytokines, in the present study the relevance of the transforming growth factors TGF-alpha and TGF-beta1 was evaluated for the diagnosis of vitality and wound age. Paraffin sections from human skin wounds due to sharp force influence, which had been collected in operations and autopsies, were investigated using immunohistochemistry. The wound age varied from a few minutes to a maximum of 6 weeks with focus on the early post-traumatic interval up to 5h. Samples from uninjured skin were available as controls. TGF-alpha (n=74) was weakly expressed in normal skin and showed a marked increase in epidermal reactivity after a wound age of approximately 10 min. The maximum was between 30 and 60 min. TGF-beta1 (n=51) revealed constitutional expression only in connective tissue. An increase of immunohistochemical reaction was partially detected even in classical stab wounds (wound age of several minutes). The immunohistochemically detectable signal concerned--presumably due to an infiltration with TGF-beta-rich thrombocytes--large parts of the traumatized skin and also the epidermal layers (cellular and interstitial marking). TGF-beta1 peaked after a post-traumatic interval of 30-60 min. Both factors, especially TGF-beta1, remained detectable in elevated levels also in older wounds with an age of days to weeks (network in granulation tissue). TGF-alpha and TGF-beta1 can efficiently contribute to the estimation of vitality and wound age based on the evaluation of cytokine patterns. In particular, this applies to TGF-beta1 because of its easier evaluation and rapid up-regulation. Similar to other cytokines, the parallel investigation of control skin from the same individual must be recommended to eliminate variation in the basal expression.

  5. Human skin: an independent peripheral endocrine organ.

    PubMed

    Zouboulis, C C

    2000-01-01

    The historical picture of the endocrine system as a set of discrete hormone-producing organs has been substituted by organs regarded as organized communities in which the cells emit, receive and coordinate molecular signals from established endocrine organs, other distant sources, their neighbors, and themselves. In this wide sense, the human skin and its tissues are targets as well as producers of hormones. Although the role of hormones in the development of human skin and its capacity to produce and release hormones are well established, little attention has been drawn to the ability of human skin to fulfil the requirements of a classic endocrine organ. Indeed, human skin cells produce insulin-like growth factors and -binding proteins, propiomelanocortin derivatives, catecholamines, steroid hormones and vitamin D from cholesterol, retinoids from diet carotenoids, and eicosanoids from fatty acids. Hormones exert their biological effects on the skin through interaction with high-affinity receptors, such as receptors for peptide hormones, neurotransmitters, steroid hormones and thyroid hormones. In addition, the human skin is able to metabolize hormones and to activate and inactivate them. These steps are overtaken in most cases by different skin cell populations in a coordinated way indicating the endocrine autonomy of the skin. Characteristic examples are the metabolic pathways of the corticotropin-releasing hormone/propiomelanocortin axis, steroidogenesis, vitamin D, and retinoids. Hormones exhibit a wide range of biological activities on the skin, with major effects caused by growth hormone/insulin-like growth factor-1, neuropeptides, sex steroids, glucocorticoids, retinoids, vitamin D, peroxisome proliferator-activated receptor ligands, and eicosanoids. At last, human skin produces hormones which are released in the circulation and are important for functions of the entire organism, such as sex hormones, especially in aged individuals, and insulin-like growth

  6. Airborne particle exposure and extrinsic skin aging.

    PubMed

    Vierkötter, Andrea; Schikowski, Tamara; Ranft, Ulrich; Sugiri, Dorothea; Matsui, Mary; Krämer, Ursula; Krutmann, Jean

    2010-12-01

    For decades, extrinsic skin aging has been known to result from chronic exposure to solar radiation and, more recently, to tobacco smoke. In this study, we have assessed the influence of air pollution on skin aging in 400 Caucasian women aged 70-80 years. Skin aging was clinically assessed by means of SCINEXA (score of intrinsic and extrinsic skin aging), a validated skin aging score. Traffic-related exposure at the place of residence was determined by traffic particle emissions and by estimation of soot in fine dust. Exposure to background particle concentration was determined by measurements of ambient particles at fixed monitoring sites. The impact of air pollution on skin aging was analyzed by linear and logistic regression and adjusted for potential confounding variables. Air pollution exposure was significantly correlated to extrinsic skin aging signs, in particular to pigment spots and less pronounced to wrinkles. An increase in soot (per 0.5 × 10(-5) per m) and particles from traffic (per 475  kg per year and square km) was associated with 20% more pigment spots on forehead and cheeks. Background particle pollution, which was measured in low residential areas of the cities without busy traffic and therefore is not directly attributable to traffic but rather to other sources of particles, was also positively correlated to pigment spots on face. These results indicate that particle pollution might influence skin aging as well.

  7. Reduction of fibroblast size/mechanical force down-regulates TGF-β type II receptor: implications for human skin aging.

    PubMed

    Fisher, Gary J; Shao, Yuan; He, Tianyuan; Qin, Zhaoping; Perry, Daniel; Voorhees, John J; Quan, Taihao

    2016-02-01

    The structural integrity of human skin is largely dependent on the quality of the dermal extracellular matrix (ECM), which is produced, organized, and maintained by dermal fibroblasts. Normally, fibroblasts attach to the ECM and thereby achieve stretched, elongated morphology. A prominent characteristic of dermal fibroblasts in aged skin is reduced size, with decreased elongation and a more rounded, collapsed morphology. Here, we show that reduced size of fibroblasts in mechanically unrestrained three-dimensional collagen lattices coincides with reduced mechanical force, measured by atomic force microscopy. Reduced size/mechanical force specifically down-regulates TGF-β type II receptor (TβRII) and thus impairs TGF-β/Smad signaling pathway. Both TβRII mRNA and protein were decreased, resulting in 90% loss of TGF-β binding to fibroblasts. Down-regulation of TβRII was associated with significantly decreased phosphorylation, DNA-binding, and transcriptional activity of its key downstream effector Smad3 and reduced expression of Smad3-regulated essential ECM components type I collagen, fibronectin, and connective tissue growth factor (CTGF/CCN2). Restoration of TβRII significantly increased TGF-β induction of Smad3 phosphorylation and stimulated expression of ECM components. Reduced expression of TβRII and ECM components in response to reduced fibroblast size/mechanical force was fully reversed by restoring size/mechanical force. Reduced fibroblast size was associated with reduced expression of TβRII and diminished ECM production, in aged human skin. Taken together, these data reveal a novel mechanism that provides a molecular basis for loss of dermal ECM, with concomitant increased fragility, which is a prominent feature of human skin aging.

  8. Skin aging: are adipocytes the next target?

    PubMed Central

    Kruglikov, Ilja L.; Scherer, Philipp E.

    2016-01-01

    Dermal white adipose tissue (dWAT) is increasingly appreciated as a special fat depot. The adipocytes in this depot exert a variety of unique effects on their surrounding cells and can undergo massive phenotypic changes. Significant modulation of dWAT content can be observed both in intrinsically and extrinsically aged skin. Specifically, skin that has been chronically photo-damaged displays a reduction of the dWAT volume, caused by the replacement of adipocytes by fibrotic structures. This is likely to be caused by the recently uncovered process described as “adipocyte-myofibroblast transition” (AMT). In addition, contributions of dermal adipocytes to the skin aging processes are also indirectly supported by spatial correlations between the prevalence of hypertrophic scarring and the appearance of signs of skin aging in different ethnic groups. These observations could elevate dermal adipocytes to prime targets in strategies aimed at counteracting skin aging. PMID:27434510

  9. Autophagy in human skin fibroblasts: Comparison between young and aged cells and evaluation of its cellular rhythm and response to Ultraviolet A radiation.

    PubMed

    Pernodet, Nadine; Dong, Kelly; Pelle, Edward

    2016-01-01

    Autophagic mechanisms play critical roles in cell maintenance. Damaged organelles that are not removed by autophagosomes, which act by engulfing and degrading these cellular components, have been linked to various pathologies. Recently, the progression of aging has also been correlated to a compromised autophagic response. Here, we report for the first time a significant reduction in autophagic levels in synchronized aged normal human skin fibroblasts as compared to young fibroblasts. We measured a 77.9% reduction in autophagy as determined by reverse transcription-polymerase chain reaction for LC3B expression, a microtubule-associated protein correlated to late stage autophagosome formation. In addition, we visualized these same changes by immunocytofluorescence with antibodies directed against LC3B. By harvesting synchronized, as well as unsynchronized cells over time, we were also able to measure for the first time a nighttime peak in autophagy that was present in young but absent in aged fibroblasts. Finally, since human skin is constantly subjected to environmentally induced oxidative stress from sunlight, we exposed fibroblasts to 10 J/cm2 ultraviolet A and found, in good agreement with current literature, not only that irradiation could partially reactivate autophagy in the aged cells, but also that this increase was phase shifted earlier from its endogenous temporal pattern because of its loss of synchronization with circadian rhythm.

  10. Skin aging and oxidative stress: Equol's anti-aging effects via biochemical and molecular mechanisms.

    PubMed

    Lephart, Edwin D

    2016-11-01

    Oxygen in biology is essential for life. It comes at a cost during normal cellular function, where reactive oxygen species (ROS) are generated by oxidative metabolism. Human skin exposed to solar ultra-violet radiation (UVR) dramatically increases ROS production/oxidative stress. It is important to understand the characteristics of human skin and how chronological (intrinsic) aging and photo-aging (extrinsic aging) occur via the impact of ROS production by cascade signaling pathways. The goal is to oppose or neutralize ROS insults to maintain good dermal health. Botanicals, as active ingredients, represent one of the largest categories used in dermatology and cosmeceuticals to combat skin aging. An emerging botanical is equol, a polyphenolic/isoflavonoid molecule found in plants and food products and via gastrointestinal metabolism from precursor compounds. Introductory sections cover oxygen, free radicals (ROS), oxidative stress, antioxidants, human skin aging, cellular/molecular ROS events in skin, steroid enzymes/receptors/hormonal actions and genetic factors in aging skin. The main focus of this review covers the characteristics of equol (phytoestrogenic, antioxidant and enhancement of extracellular matrix properties) to reduce skin aging along with its anti-aging skin influences via reducing oxidative stress cascade events by a variety of biochemical/molecular actions and mechanisms to enhance human dermal health.

  11. The electric field near human skin wounds declines with age and provides a noninvasive indicator of wound healing.

    PubMed

    Nuccitelli, Richard; Nuccitelli, Pamela; Li, Changyi; Narsing, Suman; Pariser, David M; Lui, Kaying

    2011-01-01

    Due to the transepidermal potential of 15-50 mV, inside positive, an injury current is driven out of all human skin wounds. The flow of this current generates a lateral electric field within the epidermis that is more negative at the wound edge than at regions more lateral from the wound edge. Electric fields in this region could be as large as 40 mV/mm, and electric fields of this magnitude have been shown to stimulate human keratinocyte migration toward the wounded region. After flowing out of the wound, the current returns through the space between the epidermis and stratum corneum, generating a lateral field above the epidermis in the opposite direction. Here, we report the results from the first clinical trial designed to measure this lateral electric field adjacent to human skin wounds noninvasively. Using a new instrument, the Dermacorder®, we found that the mean lateral electric field in the space between the epidermis and stratum corneum adjacent to a lancet wound in 18-25-year-olds is 107-148 mV/mm, 48% larger on average than that in 65-80-year-olds. We also conducted extensive measurements of the lateral electric field adjacent to mouse wounds as they healed and compared this field with histological sections through the wound to determine the correlation between the electric field and the rate of epithelial wound closure. Immediately after wounding, the average lateral electric field was 122 ± 9 mV/mm. When the wound is filled in with a thick, disorganized epidermal layer, the mean field falls to 79 ± 4 mV/mm. Once this epidermis forms a compact structure with only three cell layers, the mean field is 59 ± 5 mV/mm. Thus, the peak-to-peak spatial variation in surface potential is largest in fresh wounds and slowly declines as the wound closes. The rate of wound healing is slightly greater when wounds are kept moist as expected, but we could find no correlation between the amplitude of the electric field and the rate of wound

  12. The electric field near human skin wounds declines with age and provides a non-invasive indicator of wound healing

    PubMed Central

    Nuccitelli, Richard; Nuccitelli, Pamela; Li, Changyi; Narsing, Suman; Pariser, David M.; Lui, Kaying

    2011-01-01

    Due to the transepidermal potential of 15-50 mV, inside positive, an injury current is driven out of all human skin wounds. The flow of this current generates a lateral electric field within the epidermis that is more negative at the wound edge than at regions more lateral from the wound edge1. Electric fields in this region could be as large as 40 mV/mm2, and electric fields of this magnitude have been shown to stimulate human keratinocyte migration toward the wounded region3. After flowing out of the wound, the current returns through the space between the epidermis and stratum corneum, generating a lateral field above the epidermis in the opposite direction. Here we report the results from the first clinical trial designed to measure this lateral electric field adjacent to human skin wounds non-invasively. Using a new instrument, the Dermacorder®, we found that the mean lateral electric field in the space between the epidermis and stratum corneum adjacent to a lancet wound in 18-25 year olds is 107-148 mV/mm, 48% larger on average than that in 65-80 year olds. We also conducted extensive measurements of the lateral electric field adjacent to mouse wounds as they healed and compared this field with histological sections through the wound to determine the correlation between the electric field and the rate of epithelial wound closure. Immediately after wounding the average lateral electric field was 122 ± 9 mV/mm. When the wound is filled in with a thick, disorganized epidermal layer, the mean field falls to 79 ± 4 mV/mm. Once this epidermis forms a compact structure with only three cell layers, the mean field is 59 ± 5 mV/mm. Thus, the peak-to-peak spatial variation in surface potential is largest in fresh wounds and slowly declines as the wound closes. The rate of wound healing is slightly greater when wounds are kept moist as expected but we could find no correlation between the amplitude of the electric field and the rate of wound healing. PMID:22092802

  13. Skin Diseases: Cross-section of human skin

    MedlinePlus

    Skip Navigation Bar Home Current Issue Past Issues Skin Diseases Cross-section of human skin Past Issues / Fall 2008 Table of Contents For ... Logical Images, Inc. I n the areas of skin health and skin diseases, the NIH's National Institute ...

  14. Potential role of natural compounds against skin aging.

    PubMed

    Tundis, R; Loizzo, M R; Bonesi, M; Menichini, F

    2015-01-01

    Skin aging is an inevitable biological phenomenon of human life. Advancing age brings changes to all components of the integumentary system with consequent signs on the skin. Skin aging is mainly due to intrinsic (chronologic) and extrinsic aging (photo-aging). Photo-aging is a consequence of exposure to ultraviolet radiations. Despite variable economic conditions, the skin care market based on natural products continues to see strong growth. In this context, the research of naturally occurring anti-aging agents is greatly expanding and in recent years numerous plant-derived products have been investigated. This review article focuses on highlighting recent advances in current knowledge on anti-aging natural products grouped and presented according to their family origin. Plants from 35 families were reviewed. A variety of phytomolecules, derived in particular from polyphenols, triterpenes and sterols classes, demonstrated a promising activity. Among them carnosic acid, curculigoside, curcumin, glycyrrhizic acid, mangiferin, mirkoin, asiaticoside, rosmarinic acid, tectorigenin, tyrosol etc., able to inhibit tyrosinase, hyaluronidase, elastase, and collagenase, to scavenge free radicals from skin cells, to prevent trans-epidermal water loss, and to contribute to protect skin from wrinkles, were largely investigated and herein discussed. Extracts and pure compounds from Fabaceae, Asperaceae and Zingiberaceae families have shown particular interest and appear most promising in the development of anti-aging products.

  15. Nanoscale gelatinase A (MMP-2) inhibition on human skin fibroblasts of Longkong (Lansium domesticum Correa) leaf extracts for anti-aging.

    PubMed

    Manosroi, Aranya; Kumguan, Kulthida; Chankhampan, Charinya; Manosroi, Worapaka; Manosroi, Jiradej

    2012-09-01

    Leaves of Longkong which collected from Chantaburi in Thailand were extracted by the hot and cold processes using three different solvents including water, chloroform and methanol. The crude extracts were tested for antioxidative activities, tyrosinase inhibition and in vitro cytotoxicity as well as the MMP-2 inhibition activity on human skin fibroblasts for anti-aging evaluation. The hot water crude extract showed the highest antioxidative activities (DPPH radical scavenging, metal ion chelating and lipid peroxidation inhibition) with the SC50, CC50 and IPC50 values of 5.40 +/- 1.23, 32.31 +/- 0.84 and 3.29 +/- 0.30 mg/ml, respectively, and the highest tyrosinase inhibition activity with the IC50 value of 0.49 +/- 0.23 mg/ml. The extract also showed no cytotoxicity on human skin fibroblasts with the cell viability of 80.52 +/- 15.16%. It demonstrated the anti-aging potential by having the pro and active MMP-2 inhibition activity, but lower than ascorbic acid of 1.28 and 1.12 times, respectively. The semi-purified extracts were prepared from this crude extract by solvent-solvent partition. The ethyl acetate soluble fraction showed higher activities (DPPH radical scavenging, metal ion chelating and tyrosinase inhibition) than the crude extract of 23.48, 71.80 and 2.58 times, respectively. This fraction exhibited similar pro and active MMP-2 inhibitory effect to the crude extract. The results from this study have indicated the possible application of the ethyl acetate fraction of the hot water crude extract from leaves of Longkong to be developed as an anti-aging product.

  16. In vivo observation of age-related structural changes of dermal collagen in human facial skin using collagen-sensitive second harmonic generation microscope equipped with 1250-nm mode-locked Cr:Forsterite laser

    NASA Astrophysics Data System (ADS)

    Yasui, Takeshi; Yonetsu, Makoto; Tanaka, Ryosuke; Tanaka, Yuji; Fukushima, Shu-ichiro; Yamashita, Toyonobu; Ogura, Yuki; Hirao, Tetsuji; Murota, Hiroyuki; Araki, Tsutomu

    2013-03-01

    In vivo visualization of human skin aging is demonstrated using a Cr:Forsterite (Cr:F) laser-based, collagen-sensitive second harmonic generation (SHG) microscope. The deep penetration into human skin, as well as the specific sensitivity to collagen molecules, achieved by this microscope enables us to clearly visualize age-related structural changes of collagen fiber in the reticular dermis. Here we investigated intrinsic aging and/or photoaging in the male facial skin. Young subjects show dense distributions of thin collagen fibers, whereas elderly subjects show coarse distributions of thick collagen fibers. Furthermore, a comparison of SHG images between young and elderly subjects with and without a recent life history of excessive sun exposure show that a combination of photoaging with intrinsic aging significantly accelerates skin aging. We also perform image analysis based on two-dimensional Fourier transformation of the SHG images and extracted an aging parameter for human skin. The in vivo collagen-sensitive SHG microscope will be a powerful tool in fields such as cosmeceutical sciences and anti-aging dermatology.

  17. Variables influencing the frictional behaviour of in vivo human skin.

    PubMed

    Veijgen, N K; Masen, M A; van der Heide, E

    2013-12-01

    In the past decades, skin friction research has focused on determining which variables are important to affect the frictional behaviour of in vivo human skin. Until now, there is still limited knowledge on these variables. This study has used a large dataset to identify the effect of variables on the human skin, subject characteristics and environmental conditions on skin friction. The data are obtained on 50 subjects (34 males and 16 females). Friction measurements represent the friction between in vivo human skin and an aluminium sample, assessed on three anatomical locations. The coefficient of friction increased significantly (p<0.05) with increasing age, increasing ambient temperature and increasing relative air humidity. A significant inversely proportional relationship was found between friction and both the amount of hair present on the skin and the height of the subject. Other outcome variables in this study were the hydration of the skin and the skin temperature.

  18. Nutrition and aging skin: sugar and glycation.

    PubMed

    Danby, F William

    2010-01-01

    The effect of sugars on aging skin is governed by the simple act of covalently cross-linking two collagen fibers, which renders both of them incapable of easy repair. Glucose and fructose link the amino acids present in the collagen and elastin that support the dermis, producing advanced glycation end products or "AGEs." This process is accelerated in all body tissues when sugar is elevated and is further stimulated by ultraviolet light in the skin. The effect on vascular, renal, retinal, coronary, and cutaneous tissues is being defined, as are methods of reducing the glycation load through careful diet and use of supplements.

  19. Skin Ageing: Natural Weapons and Strategies

    PubMed Central

    Binic, Ivana; Lazarevic, Viktor; Ljubenovic, Milanka; Mojsa, Jelena; Sokolovic, Dusan

    2013-01-01

    The fact that the skin is the most visible organ makes us aware of the ageing process every minute. The use of plant extracts and herbs has its origins in ancient times. Chronological and photo-ageing can be easily distinguished clinically, but they share important molecular features. We tried to gather the most interesting evidence based on facts about plants and plant extracts used in antiaging products. Our main idea was to emphasize action mechanisms of these plant/herbal products, that is, their “strategies” in fighting skin ageing. Some of the plant extracts have the ability to scavenge free radicals, to protect the skin matrix through the inhibition of enzymatic degradation, or to promote collagen synthesis in the skin. There are some plants that can affect skin elasticity and tightness. Certainly, there is a place for herbal principles in antiaging cosmetics. On the other hand, there is a constant need for more evaluation and more clinical studies in vivo with emphasis on the ingredient concentration of the plant/herbal products, its formulation, safety, and duration of the antiaging effect. PMID:23431351

  20. The Microbiota of the Human Skin.

    PubMed

    Egert, Markus; Simmering, Rainer

    2016-01-01

    The aim of this chapter is to sum up important progress in the field of human skin microbiota research that was achieved over the last years.The human skin is one of the largest and most versatile organs of the human body. Owing to its function as a protective interface between the largely sterile interior of the human body and the highly microbially contaminated outer environment, it is densely colonized with a diverse and active microbiota. This skin microbiota is of high importance for human health and well-being. It is implicated in several severe skin diseases and plays a major role in wound infections. Many less severe, but negatively perceived cosmetic skin phenomena are linked with skin microbes, too. In addition, skin microorganisms, in particular on the human hands, are crucial for the field of hygiene research. Notably, apart from being only a potential source of disease and contamination, the skin microbiota also contributes to the protective functions of the human skin in many ways. Finally, the analysis of structure and function of the human skin microbiota is interesting from a basic, evolutionary perspective on human microbe interactions.Key questions in the field of skin microbiota research deal with (a) a deeper understanding of the structure (species inventory) and function (physiology) of the healthy human skin microbiota in space and time, (b) the distinction of resident and transient skin microbiota members,

  1. Evaluation and recognition of skin images with aging by support vector machine

    NASA Astrophysics Data System (ADS)

    Hu, Liangjun; Wu, Shulian; Li, Hui

    2016-10-01

    Aging is a very important issue not only in dermatology, but also cosmetic science. Cutaneous aging involves both chronological and photoaging aging process. The evaluation and classification of aging is an important issue with the medical cosmetology workers nowadays. The purpose of this study is to assess chronological-age-related and photo-age-related of human skin. The texture features of skin surface skin, such as coarseness, contrast were analyzed by Fourier transform and Tamura. And the aim of it is to detect the object hidden in the skin texture in difference aging skin. Then, Support vector machine was applied to train the texture feature. The different age's states were distinguished by the support vector machine (SVM) classifier. The results help us to further understand the mechanism of different aging skin from texture feature and help us to distinguish the different aging states.

  2. Aging-like skin changes induced by ultraviolet irradiation in an animal model of metabolic syndrome.

    PubMed

    Akase, Tomoko; Nagase, Takashi; Huang, Lijuan; Ibuki, Ai; Minematsu, Takeo; Nakagami, Gojiro; Ohta, Yasunori; Shimada, Tsutomu; Aburada, Masaki; Sugama, Junko; Sanada, Hiromi

    2012-04-01

    Both physiological skin aging and pathologic photo-aging caused by ultraviolet (UV) irradiation are mediated by latent inflammation and oxidative stress. Although numerous animal skin-aging models have used UV irradiation, most require massive doses or long-term irradiation. To establish a more refined skin-aging model, we focused on an animal model of metabolic syndrome (MS) because MS involves damage to various organs via oxidative stress or inflammation, similar to the changes associated with aging. We hypothesized that MS skin might exhibit more aging-like changes after milder, shorter-term UV irradiation than would normal animal skin under similar conditions, thus providing a useful model for skin aging. The authors therefore examined the skin from Tsumura Suzuki obese diabetic (TSOD) mice (MS model) and control Tsumura Suzuki non-obese (TSNO) mice before and after UV irradiation. Skin from TSOD mice had a thinner epidermis and dermis, a thicker fatty layer, reduced density and convolution of the fragmented collagen fibers, and upregulated expression of tumor necrosis factor (TNF)-α, a dual marker for inflammation and aging, compared to the skin from TSNO mice. UV irradiation affected TSOD skin more severely than TSNO skin, resulting in various changes resembling those in aged human skin, including damage to the dermis and subcutaneous fatty tissue, infiltration of inflammatory cells, and further upregulation of TNF-α expression. These results suggest that UV-irradiated TSOD mice may provide a new model of skin aging and imply that skin from humans with MS is more susceptible to UV- or aging-related damage than normal human skin.

  3. Role of antioxidants in the skin: anti-aging effects.

    PubMed

    Masaki, Hitoshi

    2010-05-01

    Intracellular and extracellular oxidative stress initiated by reactive oxygen species (ROS) advance skin aging, which is characterized by wrinkles and atypical pigmentation. Because UV enhances ROS generation in cells, skin aging is usually discussed in relation to UV exposure. The use of antioxidants is an effective approach to prevent symptoms related to photo-induced aging of the skin. In this review, the mechanisms of ROS generation and ROS elimination in the body are summarized. The effects of ROS generated in the skin and the roles of ROS in altering the skin are also discussed. In addition, the effects of representative antioxidants on the skin are summarized with a focus on skin aging.

  4. Human papillomaviruses and skin cancer.

    PubMed

    Smola, Sigrun

    2014-01-01

    Human papillomaviruses (HPVs) infect squamous epithelia and can induce hyperproliferative lesions. More than 120 different HPV types have been characterized and classified into five different genera. While mucosal high-risk HPVs have a well-established causal role in anogenital carcinogenesis, the biology of cutaneous HPVs is less well understood. The clinical relevance of genus beta-PV infection has clearly been demonstrated in patients suffering from epidermodysplasia verruciformis (EV), a rare inherited disease associated with ahigh rate of skin cancer. In the normal population genus beta-PV are suspected to have an etiologic role in skin carcinogenesis as well but this is still controversially discussed. Their oncogenic potency has been investigated in mouse models and in vitro. In 2009, the International Agency for Research on Cancer (IARC) classified the genus beta HPV types 5 and 8 as "possible carcinogenic" biological agents (group 2B) in EV disease. This chapter will give an overview on the knowns and unknowns of infections with genus beta-PV and discuss their potential impact on skin carcinogenesis in the general population.

  5. Penetration of nanoparticles into human skin.

    PubMed

    Liang, Xiao Wen; Xu, Zhi Ping; Grice, Jeffrey; Zvyagin, Andrei V; Roberts, Michael S; Liu, Xin

    2013-01-01

    Exposure of human skin to nanoparticles (NPs) is increasing with the development of nanotechnology and new applications of NPs in medicine. Safety concerns have sparked debate on the capacity of NPs to penetrate through skin and enter into the body. This article attempts to summarize the recent evidence on whether NPs penetrate human skin and the factors that may affect the penetration. Skin structure and penetration mechanisms are reviewed to provide background information. Size, shape, formulation, surface properties and application methods and their effects on skin penetration are specifically discussed. Finally, the relationship between skin penetration and nanotoxicity is reviewed to further emphasise the importance of the research in this area.

  6. Ultraviolet Radiation-Induced Skin Aging: The Role of DNA Damage and Oxidative Stress in Epidermal Stem Cell Damage Mediated Skin Aging

    PubMed Central

    Panich, Uraiwan; Sittithumcharee, Gunya; Rathviboon, Natwarath

    2016-01-01

    Skin is the largest human organ. Skin continually reconstructs itself to ensure its viability, integrity, and ability to provide protection for the body. Some areas of skin are continuously exposed to a variety of environmental stressors that can inflict direct and indirect damage to skin cell DNA. Skin homeostasis is maintained by mesenchymal stem cells in inner layer dermis and epidermal stem cells (ESCs) in the outer layer epidermis. Reduction of skin stem cell number and function has been linked to impaired skin homeostasis (e.g., skin premature aging and skin cancers). Skin stem cells, with self-renewal capability and multipotency, are frequently affected by environment. Ultraviolet radiation (UVR), a major cause of stem cell DNA damage, can contribute to depletion of stem cells (ESCs and mesenchymal stem cells) and damage of stem cell niche, eventually leading to photoinduced skin aging. In this review, we discuss the role of UV-induced DNA damage and oxidative stress in the skin stem cell aging in order to gain insights into the pathogenesis and develop a way to reduce photoaging of skin cells. PMID:27148370

  7. The optics of human skin

    SciTech Connect

    Anderson, R.R.; Parrish, J.A.

    1981-07-01

    An integrated review of the transfer of optical radiation into human skin is presented, aimed at developing useful models for photomedicine. The component chromophores of epidermis and stratum corneum in general determine the attenuation of radiation in these layers, moreso than does optical scattering. Epidermal thickness and melanization are important factors for UV wavelengths less than 300 nm, whereas the attenuation of UVA (320-400 nm) and visible radiation is primarily via melanin. The selective penetration of all optical wavelengths into psoriatic skin can be maximized by application of clear lipophilic liquids, which decrease regular reflectance by a refractive-index matching mechanism. Sensitivity to wavelengths less than 320 nm can be enhanced by prolonged aqueous bathing, which extracts urocanic acid and other diffusible epidermal chromophores. Optical properties of the dermis are modelled using the Kubelka-Munk approach, and calculations of scattering and absorption coefficients are presented. This simple approach allows estimates of the penetration of radiation in vivo using noninvasive measurements of cutaneous spectral remittance (diffuse reflectance). Although the blood chromophores Hb, HbO/sup 2/, and bilirubin determine dermal absorption of wavelengths longer than 320 nm, scattering by collagen fibers largely determines the depths to which these wavelengths penetrate the dermis, and profoundly modifies skin colors. An optical ''window'' exists between 600 and 1300 nm, which offers the possibility of treating large tissue volumes with certain long-wavelength photosensitizers. Moreover, whenever photosensitized action spectra extend across the near UV and/or visible spectrum, judicious choice of wavelengths allows some selection of the tissue layers directly affected.

  8. Brain-Skin Connection: Stress, Inflammation and Skin Aging

    PubMed Central

    Chen, Ying; Lyga, John

    2014-01-01

    The intricate relationship between stress and skin conditions has been documented since ancient times. Recent clinical observations also link psychological stress to the onset or aggravation of multiple skin diseases. However, the exact underlying mechanisms have only been studied and partially revealed in the past 20 years or so. In this review, the authors will discuss the recent discoveries in the field of “Brain-Skin Connection”, summarizing findings from the overlapping fields of psychology, endocrinology, skin neurobiology, skin inflammation, immunology, and pharmacology. PMID:24853682

  9. Assessing human skin with diffuse reflectance spectroscopy and colorimetry

    NASA Astrophysics Data System (ADS)

    Seo, InSeok; Liu, Yang; Bargo, Paulo R.; Kollias, Nikiforos

    2012-02-01

    Colorimetry has been used as an objective measure of perceived skin color by human eye to document and score physiological responses of the skin from external insults. CIE color space values (L*, a* and b*) are the most commonly used parameters to correlate visually perceived color attributes such as L* for pigment, a* for erythema, and b* for sallowness of the skin. In this study, we investigated the relation of Lab color scale to the amount of major skin chromophores (oxy-, deoxyhemoglobin and melanin) calculated from diffuse reflectance spectroscopy. Thirty two healthy human subjects with ages from 20 to 70 years old, skin types I-VI, were recruited for the study. DRS and colorimetry measurements were taken from the left and right cheeks, and on the right upper inner arm. The melanin content calculated from 630-700 nm range of DRS measurements was shown to correlate with the lightness of skin (L*) for most skin types. For subjects with medium-to-light complexion, melanin measured at the blue part spectrum and hemoglobin interfered on the relation of lightness of the skin color to the melanin content. The sallowness of the skin that is quantified by the melanin contribution at the blue part spectrum of DRS was found to be related to b* scale. This study demonstrates the importance of documenting skin color by assessing individual skin chromophores with diffuse reflectance spectroscopy, in comparison to colorimetry assessment.

  10. How to Select Anti-Aging Skin Care Products

    MedlinePlus

    ... skin care products Dermatologists share their insider tips Shopping for an anti-aging skin care product can ... every day can make a noticeable difference. When shopping for sunscreen, select one that offers all of ...

  11. Controlling reactive oxygen species in skin at their source to reduce skin aging.

    PubMed

    Kern, Dale G; Draelos, Zoe D; Meadows, Christiaan; James Morré, D; Morré, Dorothy M

    2010-01-01

    Activity of an age-related, superoxide-forming, cell-surface oxidase (arNOX) comparing dermis, epidermis, serum, and saliva from female and male subjects ages 28-72 years measured spectrophotometrically using reduction of ferricytochrome c correlated with oxidative skin damage as estimated from autofluoresence of skin using an Advanced Glycation End products Reader (AGE-Reader; DiagnOptics B.V., Netherlands). By reducing arNOX activity in skin with arNOX-inhibitory ingredients (NuSkin's ageLOC technology), skin appearance was improved through decreased protein cross-linking and an accelerated increase in collagen.

  12. Skin intervention of fullerene-integrated nanoemulsion in structural and collagen regeneration against skin aging.

    PubMed

    Ngan, Cheng Loong; Basri, Mahiran; Tripathy, Minaketan; Abedi Karjiban, Roghayeh; Abdul-Malek, Emilia

    2015-04-05

    Despite the fact that intrinsic oxidative stress is inevitable, the extrinsic factor such as ultraviolet radiation enhances reactive oxygen species (ROS) generation resulting in premature skin aging. Nanoemulsion was loaded with fullerene, a strong free radical scavenger, and its efficacy to provide protection and regenerative effect against ROS-induced collagen breakdown in human skin was studied. Stable fullerene nanoemulsions were formulated using high shear homogenization and ultrasonic dispersion technique. An open trial was conducted using fullerene nanoemulsion on skin twice a day for 28 days. The mean collagen score significantly increased (P<0.05) from 36.53±4.39 to 48.69±5.46 with 33.29% increment at the end of the treatment. Biophysical characteristics of skin revealed that skin hydration was increased significantly (P<0.05) from 40.91±7.01 to 58.55±6.08 corneometric units (43.12% increment) and the water was able to contain within the stratum corneum without any increased in transepidermal water loss. In the in vitro safety evaluation, fullerene nanoemulsion showed no acute toxicity on 3T3 fibroblast cell line for 48h and no indication of potential dermal irritation. Hence, the fullerene nanoemulsion may assist in protecting collagen from breakdown with cosmeceutical benefit.

  13. Photoprotection of human skin beyond ultraviolet radiation.

    PubMed

    Grether-Beck, Susanne; Marini, Alessandra; Jaenicke, Thomas; Krutmann, Jean

    2014-01-01

    Photoprotection of human skin by means of sunscreens or daily skin-care products is traditionally centered around the prevention of acute (e.g. sunburn) and chronic (e.g. skin cancer and photoaging) skin damage that may result from exposure to ultraviolet rays (UVB and UVA). Within the last decade, however, it has been appreciated that wavelengths beyond the ultraviolet spectrum, in particular visible light and infrared radiation, contribute to skin damage in general and photoaging of human skin in particular. As a consequence, attempts have been made to develop skin care/sunscreen products that not only protect against UVB or UVA radiation but provide photoprotection against visible light and infrared radiation as well. In this article, we will briefly review the current knowledge about the mechanisms responsible for visible light/infrared radiation-induced skin damage and then, based on this information, discuss strategies that have been successfully used or may be employed in the future to achieve photoprotection of human skin beyond ultraviolet radiation. In this regard we will particularly focus on the use of topical antioxidants and the challenges that result from the task of showing their efficacy.

  14. Penetration of chlorhexidine into human skin.

    PubMed

    Karpanen, T J; Worthington, T; Conway, B R; Hilton, A C; Elliott, T S J; Lambert, P A

    2008-10-01

    This study evaluated a model of skin permeation to determine the depth of delivery of chlorhexidine into full-thickness excised human skin following topical application of 2% (wt/vol) aqueous chlorhexidine digluconate. Skin permeation studies were performed on full-thickness human skin using Franz diffusion cells with exposure to chlorhexidine for 2 min, 30 min, and 24 h. The concentration of chlorhexidine extracted from skin sections was determined to a depth of 1,500 microm following serial sectioning of the skin using a microtome and analysis by high-performance liquid chromatography. Poor penetration of chlorhexidine into skin following 2-min and 30-min exposures to chlorhexidine was observed (0.157 +/- 0.047 and 0.077 +/- 0.015 microg/mg tissue within the top 100 microm), and levels of chlorhexidine were minimal at deeper skin depths (less than 0.002 microg/mg tissue below 300 microm). After 24 h of exposure, there was more chlorhexidine within the upper 100-microm sections (7.88 +/- 1.37 microg/mg tissue); however, the levels remained low (less than 1 microg/mg tissue) at depths below 300 microm. There was no detectable penetration through the full-thickness skin. The model presented in this study can be used to assess the permeation of antiseptic agents through various layers of skin in vitro. Aqueous chlorhexidine demonstrated poor permeation into the deeper layers of the skin, which may restrict the efficacy of skin antisepsis with this agent. This study lays the foundation for further research in adopting alternative strategies for enhanced skin antisepsis in clinical practice.

  15. Discovering the link between nutrition and skin aging

    PubMed Central

    Schagen, Silke K.; Zampeli, Vasiliki A.; Makrantonaki, Evgenia; Zouboulis, Christos C.

    2012-01-01

    Skin has been reported to reflect the general inner-health status and aging. Nutrition and its reflection on skin has always been an interesting topic for scientists and physicians throughout the centuries worldwide. Vitamins, carotenoids, tocopherols, flavonoids and a variety of plant extracts have been reported to possess potent anti-oxidant properties and have been widely used in the skin care industry either as topically applied agents or oral supplements in an attempt to prolong youthful skin appearance. This review will provide an overview of the current literature “linking” nutrition with skin aging. PMID:23467449

  16. Millimeter wave dosimetry of human skin.

    PubMed

    Alekseev, S I; Radzievsky, A A; Logani, M K; Ziskin, M C

    2008-01-01

    To identify the mechanisms of biological effects of mm waves it is important to develop accurate methods for evaluating absorption and penetration depth of mm waves in the epidermis and dermis. The main characteristics of mm wave skin dosimetry were calculated using a homogeneous unilayer model and two multilayer models of skin. These characteristics included reflection, power density (PD), penetration depth (delta), and specific absorption rate (SAR). The parameters of the models were found from fitting the models to the experimental data obtained from measurements of mm wave reflection from human skin. The forearm and palm data were used to model the skin with thin and thick stratum corneum (SC), respectively. The thin SC produced little influence on the interaction of mm waves with skin. On the contrary, the thick SC in the palm played the role of a matching layer and significantly reduced reflection. In addition, the palmar skin manifested a broad peak in reflection within the 83-277 GHz range. The viable epidermis plus dermis, containing a large amount of free water, greatly attenuated mm wave energy. Therefore, the deeper fat layer had little effect on the PD and SAR profiles. We observed the appearance of a moderate SAR peak in the therapeutic frequency range (42-62 GHz) within the skin at a depth of 0.3-0.4 mm. Millimeter waves penetrate into the human skin deep enough (delta = 0.65 mm at 42 GHz) to affect most skin structures located in the epidermis and dermis.

  17. The Genetics of Human Skin Disease

    PubMed Central

    DeStefano, Gina M.; Christiano, Angela M.

    2014-01-01

    The skin is composed of a variety of cell types expressing specific molecules and possessing different properties that facilitate the complex interactions and intercellular communication essential for maintaining the structural integrity of the skin. Importantly, a single mutation in one of these molecules can disrupt the entire organization and function of these essential networks, leading to cell separation, blistering, and other striking phenotypes observed in inherited skin diseases. Over the past several decades, the genetic basis of many monogenic skin diseases has been elucidated using classical genetic techniques. Importantly, the findings from these studies has shed light onto the many classes of molecules and essential genetic as well as molecular interactions that lend the skin its rigid, yet flexible properties. With the advent of the human genome project, next-generation sequencing techniques, as well as several other recently developed methods, tremendous progress has been made in dissecting the genetic architecture of complex, non-Mendelian skin diseases. PMID:25274756

  18. Bioactive compounds from natural resources against skin aging.

    PubMed

    Mukherjee, Pulok K; Maity, Niladri; Nema, Neelesh K; Sarkar, Birendra K

    2011-12-15

    Skin aging involves degradation of extracellular matrix (ECM) in both the epidermal and dermal layers, it leaves visible signs on the surface of skin and the physical properties of the skin are modified. Chronological aging is due to passage of time, whereas premature aging occurred due to some environmental factors on skin produces visible signs such as irregular dryness, dark/light pigmentation, sallowness, severe atrophy, telangiectases, premalignant lesions, laxity, leathery appearance and deep wrinkling. There are several synthetic skincare cosmetics existing in the market to treat premature aging and the most common adverse reactions of those include allergic contact dermatitis, irritant contact dermatitis, phototoxic and photo-allergic reactions. Recent trends in anti-aging research projected the use of natural products derived from ancient era after scientific validation. Ample varieties of phytomolecules such as aloin, ginsenoside, curcumin, epicatechin, asiaticoside, ziyuglycoside I, magnolol, gallic acid, hydroxychavicol, hydroxycinnamic acids, hydroxybenzoic acids, etc. scavenges free radicals from skin cells, prevent trans-epidermal water loss, include a sun protection factor (SPF) of 15 or higher contribute to protect skin from wrinkles, leading to glowing and healthy younger skin. Present era of treating aging skin has become technologically more invasive; but herbal products including botanicals are still relevant and combining them with molecular techniques outlined throughout this review will help to maximize the results and maintain the desired anti-skin aging benefits.

  19. Photoaging and chronological aging profile: Understanding oxidation of the skin.

    PubMed

    Peres, P S; Terra, V A; Guarnier, F A; Cecchini, R; Cecchini, A L

    2011-05-03

    The impact of chronological aging and photoaging on the skin is particularly concerning, especially when oxidative stress is involved. This article provides evidence of quantitative and qualitative differences in the oxidative stress generated by chronological aging and photoaging of the skin in HRS/J hairless mice. Analysis of the results revealed an increase in lipid peroxides as the skin gets older and in photoaged skin (10.086 ± 0.70 η MDA/mg and 14.303 ± 1.81 η MDA/mg protein, respectively), although protein oxidation was only verified in chronological aged skin (15.449 ± 0.99 η protein/mg protein). The difference between both skin types is the decay in the capacity of lipid membrane turnover revealed by the dislocation of older skin to the left in the chemiluminescence curve. Imbalance between antioxidant and oxidation processes was verified by the decrease in total antioxidant capacity of chronological and photoaged skins. Although superoxide dismutase remained unchanged, catalase increased in the 18 and 48-week-old skin groups and decreased in irradiated mice, demonstrating that neither enzyme is a good parameter to determine oxidative stress. The differences observed between chronological and photoaging skin represent a potential new approach to understanding the phenomenon of skin aging and a new target for therapeutic intervention.

  20. Stokes scattering matrix for human skin.

    PubMed

    Bhandari, Anak; Stamnes, Snorre; Hamre, Børge; Frette, Oyvind; Stamnes, Knut; Stamnes, Jakob J

    2012-11-01

    We use a layered model of normal human skin based on size distributions of polydisperse spherical particles and their complex refractive indices to compute the Stokes scattering matrix at wavelengths in the visible spectral band. The elements of the Stokes scattering matrix are required in a polarized radiative transfer code for a coupled air-tissue system to compute the polarized reflectance and examine how it is dependent on the vertical structure of the inherent optical properties of skin, including the phase matrix. Thus, the elements of the Stokes scattering matrix can be useful for investigating polarization-dependent light propagation in turbid optical media, such as human skin tissue.

  1. Maintaining skin integrity in the aged: a systematic review.

    PubMed

    Kottner, J; Lichterfeld, A; Blume-Peytavi, U

    2013-09-01

    Ageing is associated with structural and functional changes of the skin that result in increased vulnerability. The aim of this systematic review is to synthesize empirical evidence about the efficacy and effectiveness of basic skin care interventions for maintaining skin integrity in the aged. The databases Medline, EMBASE, CINAHL (1990-2012), Scopus, SCI (February 2013) and reference lists were searched. Inclusion criteria were primary intervention studies using skin care products in physiologically aged skin (lower age limit 50 years). Study and sample characteristics, interventions and outcomes were extracted. The methodological quality was assessed and a level of evidence was assigned. From 1535 screened articles 188 were read in full text. From these, 33 articles were included reporting results on treating dry skin conditions, and preventing incontinence-associated dermatitis and superficial ulcerations. Most studies had lower levels of evidence of 3 or 4. Skin-cleansing products containing syndets or amphoteric surfactants compared with standard soap and water washing improved skin dryness and demonstrated skin-protecting effects. Moisturizers containing humectants consistently showed statistically significant improvements in skin dryness. Skin barrier products containing occlusives reduced the occurrence of skin injuries compared with standard or no treatment. Owing to methodological limitations the current evidence base for basic skin care in the aged is weak. Using low-irritating cleansing products and humectant- or occlusive-containing moisturizers seems to be the best strategy for maintaining the skin barrier function and integrity. We know little about the effects of cleansing regimens and about the benefits of moisturizers when compared with each other.

  2. Exercise-stimulated interleukin-15 is controlled by AMPK and regulates skin metabolism and aging.

    PubMed

    Crane, Justin D; MacNeil, Lauren G; Lally, James S; Ford, Rebecca J; Bujak, Adam L; Brar, Ikdip K; Kemp, Bruce E; Raha, Sandeep; Steinberg, Gregory R; Tarnopolsky, Mark A

    2015-08-01

    Aging is commonly associated with a structural deterioration of skin that compromises its barrier function, healing, and susceptibility to disease. Several lines of evidence show that these changes are driven largely by impaired tissue mitochondrial metabolism. While exercise is associated with numerous health benefits, there is no evidence that it affects skin tissue or that endocrine muscle-to-skin signaling occurs. We demonstrate that endurance exercise attenuates age-associated changes to skin in humans and mice and identify exercise-induced IL-15 as a novel regulator of mitochondrial function in aging skin. We show that exercise controls IL-15 expression in part through skeletal muscle AMP-activated protein kinase (AMPK), a central regulator of metabolism, and that the elimination of muscle AMPK causes a deterioration of skin structure. Finally, we establish that daily IL-15 therapy mimics some of the anti-aging effects of exercise on muscle and skin in mice. Thus, we elucidate a mechanism by which exercise confers health benefits to skin and suggest that low-dose IL-15 therapy may prove to be a beneficial strategy to attenuate skin aging.

  3. Exercise-stimulated interleukin-15 is controlled by AMPK and regulates skin metabolism and aging

    PubMed Central

    Crane, Justin D; MacNeil, Lauren G; Lally, James S; Ford, Rebecca J; Bujak, Adam L; Brar, Ikdip K; Kemp, Bruce E; Raha, Sandeep; Steinberg, Gregory R; Tarnopolsky, Mark A

    2015-01-01

    Aging is commonly associated with a structural deterioration of skin that compromises its barrier function, healing, and susceptibility to disease. Several lines of evidence show that these changes are driven largely by impaired tissue mitochondrial metabolism. While exercise is associated with numerous health benefits, there is no evidence that it affects skin tissue or that endocrine muscle-to-skin signaling occurs. We demonstrate that endurance exercise attenuates age-associated changes to skin in humans and mice and identify exercise-induced IL-15 as a novel regulator of mitochondrial function in aging skin. We show that exercise controls IL-15 expression in part through skeletal muscle AMP-activated protein kinase (AMPK), a central regulator of metabolism, and that the elimination of muscle AMPK causes a deterioration of skin structure. Finally, we establish that daily IL-15 therapy mimics some of the anti-aging effects of exercise on muscle and skin in mice. Thus, we elucidate a mechanism by which exercise confers health benefits to skin and suggest that low-dose IL-15 therapy may prove to be a beneficial strategy to attenuate skin aging. PMID:25902870

  4. Optical fiber sensing of human skin emanations

    NASA Astrophysics Data System (ADS)

    Lee, S.-W.; Wang, T.; Selyanchyn, R.; Korposh, S.; James, S. W.

    2015-07-01

    An evanescent-wave optical fibre sensor modified with tetrakis(4-sulfophenyl)porphine (TSPP) and poly(allylamine hydrochloride) (PAH) bilayers using an layer-by-layer (LbL) approach was tested to measure the gas emitted from human skin. Optical intensity changes at different wavelengths in the transmission spectrum of the porphyrin-based film were induced by the human skin gas and measured as sensor response. Influence of relative humidity, which can be a major interference to sensor response, was significantly different when compared to the influence of skin emanations. Responses of the current optical sensor system could be considered as composite sensor array, where different optical wavelengths act as channels that have selective response to specific volatile compounds. Data obtained from the sensor system was analyzed through principal component analysis (PCA). This approach enabled to distinguish skin odors of different people and their altered physiological conditions after alcohol consumption.

  5. In vitro human skin penetration of diethanolamine.

    PubMed

    Kraeling, M E K; Yourick, J J; Bronaugh, R L

    2004-10-01

    Concerns about the safety of diethanolamine (DEA) have been raised by the National Toxicology Program (NTP). Therefore, we measured the extent of DEA absorption in human skin relevant to exposures from shampoos, hair dyes and body lotions. Radiolabeled [14C]-DEA was added to two commercial products from each class and applied to excised viable and non-viable human skin in flow-through diffusion cells. The products remained on the skin for 5, 30 and 24 h for shampoos, hair dyes and body lotions, respectively. After 24 h, most of the absorbed dose was found in skin: 2.8% for shampoos, 2.9% for hair dyes and 10.0% for body lotions. Only small amounts were absorbed into the receptor fluid: 0.08%, 0.09% and 0.9% for shampoos, hair dyes and body lotions respectively. There was no significant difference in the absorption of DEA through viable and non-viable skin or from product application doses of 1, 2 or 3 mg lotion/cm2. In 72 h daily repeat dose studies with a lotion, DEA appeared to accumulate in the skin (29.2%) with little diffusing out into the receptor fluid. Therefore, skin levels of DEA should not be included in estimates of systemic absorption used in exposure assessments.

  6. [Skin aging and evidence-based topical strategies].

    PubMed

    Bayerl, C

    2016-02-01

    Anti-aging in dermatology primarily focuses on the prevention of skin aging with UV protection (clothing and sunsceens), free radical scavengers (synthetic or botanic), and cell-protecting agents such as vitamin B3. For the correction of signs of early skin aging, retinoic acid derivatives in dermatological prescriptions are the best studied substances. Topical hormonal prescriptions are also an option if UV damage has not been the leading culprit for aging. Chemical peeling leads to a marked increase in collagen formation, the deaper the better. Ingredients in cream preparations can reduce superficial skin folds (polyphenols, amino acid peptides). Modulators of regular pigmentation are important for anti-aging preparations. Growth factors (plant extracts, recombinant growth factors) are not thoroughly studied regarding the cost-benefit and risk ratio. Complex precedures such as photodynamic therapy have an impact on the appearance of aged skin.

  7. Multiphoton spectroscopy of human skin in vivo

    NASA Astrophysics Data System (ADS)

    Breunig, Hans G.; Weinigel, Martin; König, Karsten

    2012-03-01

    In vivo multiphoton-intensity images and emission spectra of human skin are reported. Optical sections from different depths of the epidermis and dermis have been measured with near-infrared laser-pulse excitation. While the intensity images reveal information on the morphology, the spectra show emission characteristics of main endogenous skin fluorophores like keratin, NAD(P)H, melanin, elastin and collagen as well as of second harmonic generation induced by the excitation-light interaction with the dermal collagen network.

  8. Analyses of volatile organic compounds from human skin

    PubMed Central

    Gallagher, M.; Wysocki, C.J.; Leyden, J.J.; Spielman, A.I.; Sun, X.; Preti, G.

    2008-01-01

    Summary Background Human skin emits a variety of volatile metabolites, many of them odorous. Much previous work has focused upon chemical structure and biogenesis of metabolites produced in the axillae (underarms), which are a primary source of human body odour. Nonaxillary skin also harbours volatile metabolites, possibly with different biological origins than axillary odorants. Objectives To take inventory of the volatile organic compounds (VOCs) from the upper back and forearm skin, and assess their relative quantitative variation across 25 healthy subjects. Methods Two complementary sampling techniques were used to obtain comprehensive VOC profiles, viz., solid-phase micro extraction and solvent extraction. Analyses were performed using both gas chromatography/mass spectrometry and gas chromatography with flame photometric detection. Results Nearly 100 compounds were identified, some of which varied with age. The VOC profiles of the upper back and forearm within a subject were, for the most part, similar, although there were notable differences. Conclusions The natural variation in nonaxillary skin odorants described in this study provides a baseline of compounds we have identified from both endogenous and exogenous sources. Although complex, the profiles of volatile constituents suggest that the two body locations share a considerable number of compounds, but both quantitative and qualitative differences are present. In addition, quantitative changes due to ageing are also present. These data may provide future investigators of skin VOCs with a baseline against which any abnormalities can be viewed in searching for biomarkers of skin diseases. PMID:18637798

  9. Calendula extract: effects on mechanical parameters of human skin.

    PubMed

    Akhtar, Naveed; Zaman, Shahiq Uz; Khan, Barkat Ali; Amir, Muhammad Naeem; Ebrahimzadeh, Muhammad Ali

    2011-01-01

    The aim of this study was to evaluate the effects of newly formulated topical cream of Calendula officinalis extract on the mechanical parameters of the skin by using the cutometer. The Cutometer 580 MPA is a device that is designed to measure the mechanical properties of the skin in response to the application of negative pressure. This non-invasive method can be useful for objective and quantitative investigation of age related changes in skin, skin elasticity, skin fatigue, skin hydration, and evaluation of the effects of cosmetic and antiaging topical products. Two creams (base and formulation) were prepared for the study. Both the creams were applied to the cheeks of 21 healthy human volunteers for a period of eight weeks. Every individual was asked to come on week 1, 2, 3, 4, 5, 6, 7, and 8 and measurements were taken by using Cutometer MPA 580 every week. Different mechanical parameters of the skin measured by the cutometer were; R0, R1, R2, R5, R6, R7, and R8. These were then evaluated statistically to measure the effects produced by these creams. Using ANOVA, and t-test it was found that R0, and R6 were significant (p <0.05) whereas R1, R2, R5, R7, R8 were insignificant (p > 0.05). The instrumental measurements produced by formulation reflected significant improvements in hydration and firmness of skin.

  10. Diversity of the human skin microbiome early in life.

    PubMed

    Capone, Kimberly A; Dowd, Scot E; Stamatas, Georgios N; Nikolovski, Janeta

    2011-10-01

    Within days after birth, rapid surface colonization of infant skin coincides with significant functional changes. Gradual maturation of skin function, structure, and composition continues throughout the first years of life. Recent reports have revealed topographical and temporal variations in the adult skin microbiome. Here we address the question of how the human skin microbiome develops early in life. We show that the composition of cutaneous microbial communities evolves over the first year of life, showing increasing diversity with age. Although early colonization is dominated by Staphylococci, their significant decline contributes to increased population evenness by the end of the first year. Similar to what has been shown in adults, the composition of infant skin microflora appears to be site specific. In contrast to adults, we find that Firmicutes predominate on infant skin. Timely and proper establishment of healthy skin microbiome during this early period might have a pivotal role in denying access to potentially infectious microbes and could affect microbiome composition and stability extending into adulthood. Bacterial communities contribute to the establishment of cutaneous homeostasis and modulate inflammatory responses. Early microbial colonization is therefore expected to critically affect the development of the skin immune function.

  11. Diversity of the Human Skin Microbiome Early in Life

    PubMed Central

    Capone, Kimberly A; Dowd, Scot E; Stamatas, Georgios N; Nikolovski, Janeta

    2011-01-01

    Within days after birth, rapid surface colonization of infant skin coincides with significant functional changes. Gradual maturation of skin function, structure, and composition continues throughout the first years of life. Recent reports have revealed topographical and temporal variations in the adult skin microbiome. Here we address the question of how the human skin microbiome develops early in life. We show that the composition of cutaneous microbial communities evolves over the first year of life, showing increasing diversity with age. Although early colonization is dominated by Staphylococci, their significant decline contributes to increased population evenness by the end of the first year. Similar to what has been shown in adults, the composition of infant skin microflora appears to be site specific. In contrast to adults, we find that Firmicutes predominate on infant skin. Timely and proper establishment of healthy skin microbiome during this early period might have a pivotal role in denying access to potentially infectious microbes and could affect microbiome composition and stability extending into adulthood. Bacterial communities contribute to the establishment of cutaneous homeostasis and modulate inflammatory responses. Early microbial colonization is therefore expected to critically affect the development of the skin immune function. PMID:21697884

  12. Measuring skin aging using optical coherence tomography in vivo: a validation study

    NASA Astrophysics Data System (ADS)

    Trojahn, Carina; Dobos, Gabor; Richter, Claudia; Blume-Peytavi, Ulrike; Kottner, Jan

    2015-04-01

    Dermal and epidermal structures in human skin change during intrinsic and extrinsic aging. Epidermal thickness is one of the most often reported parameters for the assessment of skin aging in cross-sectional images captured by optical coherence tomography (OCT). We aimed to identify further parameters for the noninvasive measurement of skin aging of sun-exposed and sun-protected areas utilizing OCT. Based on a literature review, seven parameters were inductively developed. Three independent raters assessed these parameters using four-point scales on images of female subjects of two age groups. All items could be detected and quantified in our sample. Interrater agreement ranged between 25.0% and 83.3%. The item scores "stratum corneum reflectivity," "upper dermal reflectivity," and "dermoepidermal contrast" showed significant differences between age groups on the volar and dorsal forearm indicating that they were best able to measure changes during skin aging. "Surface unevenness" was associated with the skin roughness parameters, Rz and Rmax, on the inner upper arm and volar forearm supporting the criterion validity of this parameter on sun-protected skin areas. Based on the interrater agreement and the ability to differentiate between age groups, these four parameters are being considered as the best candidates for measuring skin aging in OCT images.

  13. Occupational exposure to natural UV radiation and premature skin ageing.

    PubMed

    Lastowiecka-Moras, Elżbieta; Bugajska, Joanna; Młynarczyk, Beata

    2014-01-01

    The skin is the part of the human body most vulnerable to ultraviolet (UV) radiation. The spectrum of the negative effects of UV radiation on the skin ranges from acute erythema to carcinogenesis. Between these extreme conditions, there are other common skin lesions, e.g., photoageing. The aim of this study was to assess the skin for signs of photoageing in a group of 52 men occupationally exposed to natural UV radiation. There were 2 types of examinations: an examination of skin condition (moisture, elasticity, sebum, porosity, smoothness, discolourations and wrinkles) with a device for diagnosing the skin, and a dermatological examination. The results of both examinations revealed a higher percentage of skin characteristics typical for photoageing in outdoor workers compared to the general population.

  14. A long-standing hyperglycaemic condition impairs skin barrier by accelerating skin ageing process.

    PubMed

    Park, Hwa-Young; Kim, Jae-Hong; Jung, Minyoung; Chung, Choon Hee; Hasham, Rosnani; Park, Chang Seo; Choi, Eung Ho

    2011-12-01

    Uncontrolled chronic hyperglycaemia including type 2 diabetes mellitus (DM) induces many skin problems related to chronic impaired skin barrier state. However, little is known about the skin barrier state of chronic hyperglycaemia patients, the dysfunction of which may be a major cause of their skin problems. In this study, we investigated whether a long-standing hyperglycaemic condition including type 2 DM impairs skin barrier homoeostasis in proportion to the duration and its pathomechanism. We utilized the Otsuka Long-Evans Tokushima Fatty (OLETF) rats as an animal model of long-standing hyperglycaemia and Long-Evans Tokushima Otsuka rats as a control strain. We confirmed that a long-standing hyperglycaemia delayed skin barrier homoeostasis, which correlated with haemoglobin A1c levels. OLETF rats as a long-standing hyperglycaemia model exhibited decreased epidermal lipid synthesis and antimicrobial peptide expression with increasing age. Decreased epidermal lipid synthesis accounted for decreased lamellar body production. In addition, OLETF rats had significantly higher serum levels of advanced glycation end products (AGEs) and elevated levels of the receptor for AGE in the epidermis. A long-standing hyperglycaemic condition impairs skin barrier function including permeability and antimicrobial barriers by accelerating skin ageing process in proportion to the duration of hyperglycaemia, which could be a major pathophysiology underlying cutaneous complications of DM.

  15. Sleep and Human Aging.

    PubMed

    Mander, Bryce A; Winer, Joseph R; Walker, Matthew P

    2017-04-05

    Older adults do not sleep as well as younger adults. Why? What alterations in sleep quantity and quality occur as we age, and are there functional consequences? What are the underlying neural mechanisms that explain age-related sleep disruption? This review tackles these questions. First, we describe canonical changes in human sleep quantity and quality in cognitively normal older adults. Second, we explore the underlying neurobiological mechanisms that may account for these human sleep alterations. Third, we consider the functional consequences of age-related sleep disruption, focusing on memory impairment as an exemplar. We conclude with a discussion of a still-debated question: do older adults simply need less sleep, or rather, are they unable to generate the sleep that they still need?

  16. Trends in aging and skin care: Ayurvedic concepts

    PubMed Central

    Datta, Hema Sharma; Paramesh, Rangesh

    2010-01-01

    The association between Ayurveda, anti-aging and cosmeceuticals is gaining importance in the beauty, health and wellness sector. Ayurvedic cosmeceuticals date back to the Indus Valley Civilization. Modern research trends mainly revolve around principles of anti-aging activity described in Ayurveda: Vayasthapana (age defying), Varnya (brighten skin-glow), Sandhaniya (cell regeneration), Vranaropana (healing), Tvachya (nurturing), Shothahara (anti-inflammatory), Tvachagnivardhani (strengthening skin metabolism) and Tvagrasayana (retarding aging). Many rasayana plants such as Emblica officinalis (Amla) and Centella asiatica (Gotukola) are extensively used. PMID:21836797

  17. Absorption of lawsone through human skin.

    PubMed

    Kraeling, Margaret E K; Bronaugh, Robert L; Jung, Connie T

    2007-01-01

    Lawsone (2-hydroxy-1,4-naphthoquinone) is the principal color ingredient in henna, a color additive approved with limitations for coloring hair by the Food and Drug Administration (FDA) under 21 CFR 73.2190. In 2002, the scientific committee on cosmetics and non-food products (SCCNFP), now known as the scientific committee for consumer products (SCCP), evaluated the safety of lawsone as a coloring agent in hair dye products of the European Union (EU). The SCCNFP concluded that lawsone was mutagenic and not suitable for use as a hair coloring agent. As a result, studies were conducted to measure the extent of lawsone absorption through human skin. Lawsone skin absorption was determined from two hair coloring products and two shampoo products, all containing henna. [(14)C]-Lawsone (sp. act. 22.9 mCi/mmol) was added to each commercial product and the products were applied to dermatomed, nonviable human skin mounted in flow-through diffusion cells perfused with a physiological buffer (HEPES-buffered Hanks' balanced salt solution, pH 7.4). Products remained on the skin for 5 minutes (shampoos) and 1 hour (hair color paste). For the henna hair paste products, 0.3 and 1.3% of the applied dose was absorbed into the receptor fluid in 24 hours while 2.2 and 4.0% remained in the skin. For both henna shampoo products, 0.3% of the applied dose was absorbed into the receptor fluid at 24 hours while 3.6 and 6.8% remained in the skin. For all products, most of the lawsone applied was washed from the surface of the skin (83-102%) at the end of the exposure period. Extended absorption studies were conducted for 72 hours to determine if skin levels of lawsone in the 24 hour studies might eventually be percutaneously absorbed. These studies determined that the majority of the lawsone remained in the skin with only a small but significant increase (for three out of four products) in receptor fluid values. Therefore, it appears that receptor fluid values would give a good estimate of

  18. The analysis of aging skin based on multiphoton microscopy

    NASA Astrophysics Data System (ADS)

    Wu, Shulian; Li, Hui; Zhang, Xiaoman; Li, Zhifang; Xu, Shufei

    2010-11-01

    Aging is a very important issue not only in dermatology, but also in cosmetic science. Cutaneous aging involves both chronological and photoaging aging process. The chronological aging is induced with the passage of time. And the photoaging skin is the extrinsic aging caused by sun exposure. The aim of this study is to use multiphoton microscopy (MPM) in vivo to assess intrinsic-age-related and photo-age-related difference. The changes of dermal collagen are measured in quantitively. The algorithm that we used automatically produced the transversal dermal map from MPM. Others, the texture of dermis are analyzed by Fourier transform and Gray Level Co-occurrence Matrix. And the object extraction in textured images is proposed based on the method in object edge extraction, and the aim of it is to detect the object hidden in the skin texture in difference aging skin. The result demonstrates that the approach is effective in detecting the object in epidermis and dermis textured image in different aging skin. It could help to further understand the aging mechanism.

  19. Functional and physiological characteristics of the aging skin.

    PubMed

    Farage, Miranda A; Miller, Kenneth W; Elsner, Peter; Maibach, Howard I

    2008-06-01

    As life expectancy in the U.S. increases - and with it the proportion of the aged in the population - appropriate care of elderly skin becomes a medical concern of increasing importance. As skin ages, the intrinsic structural changes that are a natural consequence of passing time are inevitably followed by subsequent physiological changes that affect the skin's ability to function as the interface between internal and external environments. The pH of the skin surface increases with age, increasing its susceptibility to infection. Neurosensory perception of superficial pain is diminished both in intensity and speed of perception (increasing the risk of thermal injury); deep tissue pain, however, may be enhanced. A decline in lipid content as the skin ages inhibits the permeability of nonlipophilic compounds, reducing the efficacy of some topical medications. Allergic and irritant reactions are blunted, as is the inflammatory response, compromising the ability of the aged skin to affect wound repair. These functional impairments (although a predictable consequence of intrinsic structural changes) have the potential to cause significant morbidity in the elderly patient and may, as well, be greatly exacerbated by extrinsic factors like photodamage. As numbers of the elderly increase, medical as well as cosmetic dermatological interventions will be necessary to optimize the quality of life for this segment of the population.

  20. The ageing of the blood supply and the lymphatic drainage of the skin.

    PubMed

    Ryan, Terence

    2004-01-01

    The anatomy and functions of the blood and lymph vessels of human skin are described. Variation in these due to site, ageing and events during life consequent to exposure to a threatening environment are emphasised. Gradual atrophy and greater heterogeneity are features of ageing. Responses to injury and repair are complex and the interaction of mechanical signals distorting skin cells with numerous chemical signals are referred to. The lymphatics are part of an immunosurveillance system to monitor skin barrier penetration. The review attempts to draw attention to key recent advances in our understanding of the cytokine and growth factor production of the skin in the context of previous mainly physiological reviews especially influenced by 50 years of clinical practice as a dermatologist with an eye on both the skin and the fields of microcirculation and lymphology.

  1. Skin aging: molecular pathology, dermal remodelling and the imaging revolution.

    PubMed

    Newton, V L; Mcconnell, J C; Hibbert, S A; Graham, H K; Watson, R E

    2015-12-01

    Skin is a multifunctional organ but, alongside every other organ system, is subject to both intrinsic (chronological) and extrinsic (environmental) aging, resulting in a loss of functional capacity. Cutaneous aging manifests as an observable change in the external appearance of the skin, the major accelerator of the aging process being our interactions with our environment, such as chronic exposure to solar irradiation (UV, IR or visible wavelengths of light). The aim of this contribution, therefore, was to provide a review of the pathological mechanisms which may play roles in the development of extrinsic, mainly photo-, aging and to review how these molecular changes impact on the structure of the organ as a whole, resulting in loss of function. Finally, we will describe the advances which are occurring in imaging techniques which may allow further characterisation of aged skin.

  2. Reduced dermis thickness and AGE accumulation in diabetic abdominal skin.

    PubMed

    Niu, Yiwen; Cao, Xiaozan; Song, Fei; Xie, Ting; Ji, Xiaoyun; Miao, Mingyuan; Dong, Jiaoyun; Tian, Ming; Lin, Yuan; Lu, Shuliang

    2012-09-01

    Dermatological problems in diabetes might play an important role in the spontaneous ulcers and impaired wound healing that are seen in diabetic patients. Investigation of the cause of diabetic skin disorders is critical for identifying effective treatment. The abdominal full-thickness skin tissues of 33 patients (14 nondiabetic and 19 diabetic) were analyzed. The cell viability and malondialdehyde (MDA) production of fibroblasts were measured after advanced glycosylation end product (AGE)-bovine serum albumin (BSA) exposure. Cutaneous histological observation showed reduced thickness of the diabetic abdominal dermis with morphological characteristics of obscured multilayer epithelium and shortened, thinned, and disorganized collagen fibrils with focal chronic inflammatory cell infiltration when compared with controls of the same age. Accumulation of AGEs in diabetic skin was prominent. Less hydroxyproline, higher myeloperoxidase activity, and increased MDA content were detected in diabetic skin. In vitro, the time- and dose-dependent inhibitory effects of AGE-BSA on fibroblast viability as well as the fact that AGE-BSA could promote MDA production of fibroblasts were shown. It is shown that the accumulation of AGEs in diabetic skin tissue induces an oxidative damage of fibroblasts and acts as an important contributor to the thinner diabetic abdominal dermis. The authors believe that diabetic cutaneous properties at baseline may increase the susceptibility to injury, and diabetic wounds possess atypical origin in the repair process.

  3. Soil adherence to human skin

    SciTech Connect

    Driver, J.H.; Konz, J.J.; Whitmyre, G.K. )

    1989-12-01

    Dermal exposure to soils contaminated with toxic chemicals represents a potential public health hazard. These soils, contaminated with chemicals such as PCBs and dioxins, may be found at various locations throughout the US. Furthermore, dermal contact with pesticide-containing particles and contaminated soil particles is of importance for exposures to agricultural workers who reenter fields after pesticide application. With respect to dermal exposure to pesticide-contaminated particulate matter, several occurrences of human toxicity to ethyl parathion in citrus groves have been reported. These exposures resulted from dermal contact with high concentrations of the toxic transformation product paraoxon in soil dust contaminated as a result of application of pesticide to the overhead foliage of trees. To assess dermal exposure to chemically-contaminated soil at sites of concern, dermal adherence of soil must be determined prior to the assessment of dermal absorption. The purpose of the experiment reported herein was to determine the amount of soil (mg/cm{sup 2}) that adheres to adult hands under various soil conditions. These conditions include the type of soil, the organic content of the soil, and the particle size of the soil.

  4. Using FLIM in the study of permeability barrier function of aged and young skin

    NASA Astrophysics Data System (ADS)

    Xu, P.; Choi, E. H.; Man, M. Q.; Crumrine, D.; Mauro, T.; Elias, P.

    2006-02-01

    Aged skin commonly is afflicted by inflammatory skin diseases or xerosis/eczema that can be triggered or exacerbated by impaired epidermal permeability barrier homeostasis. It has been previously described a permeability barrier defect in humans of advanced age (> 75 years), which in a murine analog >18 mos, could be attributed to reduced lipid synthesis synthesis. However, the functional abnormality in moderately aged mice is due not to decreased lipid synthesis, but rather to a specific defect in stratum corneum (SC) acidification causing impaired lipid processing processing. Endogenous Na +/H + antiporter (NHE1) level was found declined in moderately aged mouse epidermis. This acidification defect leads to perturbed permeability barrier homeostasis through more than one pathways, we addressed suboptimal activation of the essential, lipid-processing enzyme, β-glucocerebrosidase (BGC) is linked to elevated SC pH. Finally, the importance of the epidermis acidity is shown by the normalization of barrier function after exogenous acidification of moderately aged skin.

  5. Rapid mesoscale multiphoton microscopy of human skin

    PubMed Central

    Balu, Mihaela; Mikami, Hideharu; Hou, Jue; Potma, Eric O.; Tromberg, Bruce J.

    2016-01-01

    We present a multiphoton microscope designed for mesoscale imaging of human skin. The system is based on two-photon excited fluorescence and second-harmonic generation, and images areas of ~0.8x0.8 mm2 at speeds of 0.8 fps (800x800 pixels; 12 frame averages) for high signal-to-noise ratio, with lateral and axial resolutions of 0.5µm and 3.3µm, respectively. The main novelty of this instrument is the design of the scan head, which includes a fast galvanometric scanner, optimized relay optics, a beam expander and high NA objective lens. Computed aberrations in focus are below the Marechal criterion of 0.07λ rms for diffraction-limited performance. We demonstrate the practical utility of this microscope by ex-vivo imaging of wide areas in normal human skin. PMID:27895980

  6. Tryptophan hydroxylase expression in human skin cells.

    PubMed

    Slominski, Andrzej; Pisarchik, Alexander; Johansson, Olle; Jing, Chen; Semak, Igor; Slugocki, George; Wortsman, Jacobo

    2003-10-15

    We attempted to further characterize cutaneous serotoninergic and melatoninergic pathways evaluating the key biosynthetic enzyme tryptophan hydroxylase (TPH). There was wide expression of TPH mRNA in whole human skin, cultured melanocytes and melanoma cells, dermal fibroblasts, squamous cell carcinoma cells and keratinocytes. Gene expression was associated with detection of TPH immunoreactive species by Western blotting. Characterization of the TPH immunoreactive species performed with two different antibodies showed expression of the expected protein (55-60 kDa), and of forms with higher and lower molecular weights. This pattern of broad spectrum of TPH expression including presumed degradation products suggests rapid turnover of the enzyme, as previously reported in mastocytoma cells. RP-HPLC of skin extracts showed fluorescent species with the retention time of serotonin and N-acetylserotonin. Immunocytochemistry performed in skin biopsies localized TPH immunoreactivity to normal and malignant melanocytes. We conclude that while the TPH mRNA and protein are widely expressed in cultured normal and pathological epidermal and dermal skin cells, in vivo TPH expression is predominantly restricted to cells of melanocytic origin.

  7. Ameliorating Effect of Akebia quinata Fruit Extracts on Skin Aging Induced by Advanced Glycation End Products.

    PubMed

    Shin, Seoungwoo; Son, Dahee; Kim, Minkyung; Lee, Seungjun; Roh, Kyung-Baeg; Ryu, Dehun; Lee, Jongsung; Jung, Eunsun; Park, Deokhoon

    2015-11-12

    The accumulation of free radicals and advanced glycation end products (AGEs) in the skin plays a very important role in skin aging. Both are known to interact with each other. Therefore, natural compounds or extracts that possess both antioxidant and antiglycation activities might have great antiageing potential. Akebia quinata fruit extract (AQFE) has been used to treat urinary tract inflammatory disease in traditional Korean and Chinese medicines. In the present study, AQFE was demonstrated to possess antioxidant and antiglycation activity. AQFE protects human dermal fibroblasts (HDFs) from oxidative stress and inhibits cellular senescence induced by oxidative stress. We also found that AQFE inhibits glycation reaction between BSA and glucose. The antiglycation activity of AQFE was dose-dependent. In addition, the antiglycation activity of AQFE was confirmed in a human skin explant model. AQFE reduced CML expression and stimulated fibrillin-1 expression in comparison to the methyglyoxal treatment. In addition, the possibility of the extract as an anti-skin aging agent has also been clinically validated. Our analysis of the crow's feet wrinkle showed that there was a decrease in the depth of deep furrows in RI treated with AQFE cream over an eight-week period. The overall results suggest that AQFE may work as an anti-skin aging agent by preventing oxidative stress and other complications associated with AGEs formation.

  8. The isolated perfused human skin flap model: A missing link in skin penetration studies?

    PubMed

    Ternullo, Selenia; de Weerd, Louis; Flaten, Gøril Eide; Holsæter, Ann Mari; Škalko-Basnet, Nataša

    2017-01-01

    Development of effective (trans)dermal drug delivery systems requires reliable skin models to evaluate skin drug penetration. The isolated perfused human skin flap remains metabolically active tissue for up to 6h during in vitro perfusion. We introduce the isolated perfused human skin flap as a close-to-in vivo skin penetration model. To validate the model's ability to evaluate skin drug penetration the solutions of a hydrophilic (calcein) and a lipophilic (rhodamine) fluorescence marker were applied. The skin flaps were perfused with modified Krebs-Henseleit buffer (pH7.4). Infrared technology was used to monitor perfusion and to select a well-perfused skin area for administration of the markers. Flap perfusion and physiological parameters were maintained constant during the 6h experiments and the amount of markers in the perfusate was determined. Calcein was detected in the perfusate, whereas rhodamine was not detectable. Confocal images of skin cross-sections shoved that calcein was uniformly distributed through the skin, whereas rhodamine accumulated in the stratum corneum. For comparison, the penetration of both markers was evaluated on ex vivo human skin, pig skin and cellophane membrane. The proposed perfused flap model enabled us to distinguish between the penetrations of the two markers and could be a promising close-to-in vivo tool in skin penetration studies and optimization of formulations destined for skin administration.

  9. Differences in visual perception of age and attractiveness of female facial and body skin.

    PubMed

    Fink, B; Matts, P J; Röder, S; Johnson, R; Burquest, M

    2011-04-01

    Perception of age and health is critical in the judgement of attractiveness. The few studies conducted on the significance of apparent skin condition on human physical appearance have studied faces alone or isolated fields of images facial skin. Little is known about whether perception of the face matches that of other body parts or if body skin affects overall age and attractiveness perception when presented in combination with facial skin. We hypothesized that independent presentation of female faces, chests and arms (including hands) - cropped from a full face and upper body image - would result in significant differences in perception of age and attractiveness compared to the corresponding composite. Furthermore, we sought to investigate whether relatively young and attractive looking skin on selected, individual parts of the body affects overall perception. Digital photographs of 52 women aged 45-65 years were collected and processed to yield four derivative sets of images: One set showed the composite of all features, i.e. the face, the chest and the arms, whereas the other three were cropped carefully to show each part of the upper body described above independently. A total of 240 participants judged these faces for perceived age and attractiveness. Our results showed significant differences in perception with the chest and the arms being judged significantly younger than the face or composite image of the same women. Moreover, arms and chest images were perceived as more attractive than face and composite images. Finally, regression analysis indicated that differences between the perceived and chronological values of overall age perception could be predicted by age perception of the face and arms. These results continue to support the significance of facial age perception in assessment of a woman's age, but highlight that body skin also plays a role in overall age impression.

  10. Preparation of Inactivated Human Skin Using High Hydrostatic Pressurization for Full-Thickness Skin Reconstruction

    PubMed Central

    Liem, Pham Hieu; Morimoto, Naoki; Mahara, Atsushi; Jinno, Chizuru; Shima, Koji; Ogino, Shuichi; Sakamoto, Michiharu; Kakudo, Natsuko; Inoie, Masukazu; Kusumoto, Kenji; Fujisato, Toshia; Suzuki, Shigehiko; Yamaoka, Tetsuji

    2015-01-01

    We have reported that high-hydrostatic-pressure (HHP) technology is safe and useful for producing various kinds of decellularized tissue. However, the preparation of decellularized or inactivated skin using HHP has not been reported. The objective of this study was thus to prepare inactivated skin from human skin using HHP, and to explore the appropriate conditions of pressurization to inactivate skin that can be used for skin reconstruction. Human skin samples of 8 mm in diameter were packed in bags filled with normal saline solution (NSS) or distilled water (DW), and then pressurized at 0, 100, 150, 200 and 1000 MPa for 10 minutes. The viability of skin after HHP was evaluated using WST-8 assay. Outgrowth cells from pressurized skin and the viability of pressurized skin after cultivation for 14 days were also evaluated. The pressurized skin was subjected to histological evaluation using hematoxylin and eosin staining, scanning electron microscopy (SEM), immunohistochemical staining of type IV collagen for the basement membrane of epidermis and capillaries, and immunohistochemical staining of von Willebrand factor (vWF) for capillaries. Then, human cultured epidermis (CE) was applied on the pressurized skin and implanted into the subcutis of nude mice; specimens were subsequently obtained 14 days after implantation. Skin samples pressurized at more than 200 MPa were inactivated in both NSS and DW. The basement membrane and capillaries remained intact in all groups according to histological and immunohistological evaluations, and collagen fibers showed no apparent damage by SEM. CE took on skin pressurized at 150 and 200 MPa after implantation, whereas it did not take on skin pressurized at 1000 MPa. These results indicate that human skin could be inactivated after pressurization at more than 200 MPa, but skin pressurized at 1000 MPa had some damage to the dermis that prevented the taking of CE. Therefore, pressurization at 200 MPa is optimal for preparing

  11. The top skin-associated genes: a comparative analysis of human and mouse skin transcriptomes.

    PubMed

    Gerber, Peter Arne; Buhren, Bettina Alexandra; Schrumpf, Holger; Homey, Bernhard; Zlotnik, Albert; Hevezi, Peter

    2014-06-01

    The mouse represents a key model system for the study of the physiology and biochemistry of skin. Comparison of skin between mouse and human is critical for interpretation and application of data from mouse experiments to human disease. Here, we review the current knowledge on structure and immunology of mouse and human skin. Moreover, we present a systematic comparison of human and mouse skin transcriptomes. To this end, we have recently used a genome-wide database of human gene expression to identify genes highly expressed in skin, with no, or limited expression elsewhere - human skin-associated genes (hSAGs). Analysis of our set of hSAGs allowed us to generate a comprehensive molecular characterization of healthy human skin. Here, we used a similar database to generate a list of mouse skin-associated genes (mSAGs). A comparative analysis between the top human (n=666) and mouse (n=873) skin-associated genes (SAGs) revealed a total of only 30.2% identity between the two lists. The majority of shared genes encode proteins that participate in structural and barrier functions. Analysis of the top functional annotation terms revealed an overlap for morphogenesis, cell adhesion, structure, and signal transduction. The results of this analysis, discussed in the context of published data, illustrate the diversity between the molecular make up of skin of both species and grants a probable explanation, why results generated in murine in vivo models often fail to translate into the human.

  12. Characterization of porcine skin as a model for human skin studies using infrared spectroscopic imaging.

    PubMed

    Kong, Rong; Bhargava, Rohit

    2011-06-07

    Porcine skin is often considered a substitute for human skin based on morphological and functional data, for example, for transdermal drug diffusion studies. A chemical, structural and temporal characterization of porcine skin in comparison to human skin is not available but will likely improve our understanding of this porcine skin model. Here, we employ Fourier transform infrared (FT-IR) spectroscopic imaging to holistically measure chemical species as well as spatial structure as a function of time to characterize porcine skin as a model for human skin. Porcine skin was found to resemble human skin spectroscopically and differences are elucidated. Cryo-prepared fresh porcine skin samples for spectroscopic imaging were found to be stable over time and small variations are observed. Hence, we extended characterization to the use of this model for dynamic processes. In particular, the capacity and stability of this model in transdermal diffusion is examined. The results indicate that porcine skin is likely to be an attractive tool for studying diffusion dynamics of materials in human skin.

  13. Human skin pigmentation, migration and disease susceptibility

    PubMed Central

    Jablonski, Nina G.; Chaplin, George

    2012-01-01

    Human skin pigmentation evolved as a compromise between the conflicting physiological demands of protection against the deleterious effects of ultraviolet radiation (UVR) and photosynthesis of UVB-dependent vitamin D3. Living under high UVR near the equator, ancestral Homo sapiens had skin rich in protective eumelanin. Dispersals outside of the tropics were associated with positive selection for depigmentation to maximize cutaneous biosynthesis of pre-vitamin D3 under low and highly seasonal UVB conditions. In recent centuries, migrations and high-speed transportation have brought many people into UVR regimes different from those experienced by their ancestors and, accordingly, exposed them to new disease risks. These have been increased by urbanization and changes in diet and lifestyle. Three examples—nutritional rickets, multiple sclerosis (MS) and cutaneous malignant melanoma (CMM)—are chosen to illustrate the serious health effects of mismatches between skin pigmentation and UVR. The aetiology of MS in particular provides insight into complex and contingent interactions of genetic and environmental factors necessary to trigger lethal disease states. Low UVB levels and vitamin D deficiencies produced by changes in location and lifestyle pose some of the most serious disease risks of the twenty-first century. PMID:22312045

  14. Human skin organ culture for assessment of chemically induced skin damage

    PubMed Central

    Varani, James

    2015-01-01

    The move away from animal models for skin safety testing is inevitable. It is a question of when, not if. As skin safety studies move away from traditional animal-based approaches, a number of replacement technologies are becoming available. Human skin in organ culture is one such technology. Organ-cultured skin has several features that distinguish it from other technologies. First and foremost, organ-cultured skin is real skin. Almost by definition, therefore, it approximates the intact skin better than other alternative models. Organ culture is an easy-to-use and relatively inexpensive approach to preclinical safety assessment. Although organ culture is not likely to replace high-throughput enzyme assays or monolayer culture/skin equivalent cultures for initial compound assessment, organ culture should find use when the list of compounds to be evaluated is small and when simpler models have narrowed the dose range. Organ-cultured skin also provides a platform for mechanistic studies. PMID:26989431

  15. Diffusion of (2-/sup 14/C)diazepam across hairless mouse skin and human skin

    SciTech Connect

    Koch, R.L.; Palicharla, P.; Groves, M.J.

    1987-05-01

    The objectives of this study were to investigate the absorption of diazepam applied topically to the hairless mouse in vivo and to determine the diffusion of diazepam across isolated hairless mouse skin and human skin. (/sup 14/C)Diazepam was readily absorbed after topical administration to the intact hairless mouse, a total of 75.8% of the /sup 14/C-label applied being recovered in urine and feces. Diazepam was found to diffuse across human and hairless mouse skin unchanged in experiments with twin-chambered diffusion cells. The variation in diffusion rate or the flux for both human and mouse tissues was greater among specimens than between duplicate or triplicate trials for a single specimen. Fluxes for mouse skin (stratum corneum, epidermis, and dermis) were greater than for human skin (stratum corneum and epidermis): 0.35-0.61 microgram/cm2/h for mouse skin vs 0.24-0.42 microgram/cm2/h for human skin. The permeability coefficients for mouse skin ranged from 1.4-2.4 X 10(-2)cm/h compared with 0.8-1.4 X 10(-2)cm/h for human skin. Although human stratum corneum is almost twice the thickness of that of the hairless mouse, the diffusion coefficients for human skin were 3-12 times greater (0.76-3.31 X 10(-6) cm2/h for human skin vs 0.12-0.27 X 10(-6) cm2/h for hairless mouse) because of a shorter lag time for diffusion across human skin. These differences between the diffusion coefficients and diffusion rates (or permeability coefficients) suggest that the presence of the dermis may present some barrier properties. In vitro the dermis may require complete saturation before the diazepam can be detected in the receiving chamber.

  16. Structure and function of the human skin microbiome.

    PubMed

    Schommer, Nina N; Gallo, Richard L

    2013-12-01

    An abundant and diverse collection of bacteria, fungi, and viruses inhabits the human skin. These microorganisms vary between individuals and between different sites on the skin. The factors responsible for the unique variability of the skin microbiome are only partly understood, but results suggest that host genetic and environmental influences play a major role. Today, the steady accumulation of data describing the skin microbiome, combined with experiments designed to test the biological functions of surface microbes, has provided new insights into links between human physiology and skin microbiota. This review describes some of the current information regarding the skin microbiome and its impact on human health. Specifically, we summarize the present understanding of the function of microbe-host interactions on the skin and highlight some unique features that distinguish skin commensal organisms from pathogenic microbes.

  17. Structure and function of the human skin microbiome

    PubMed Central

    Schommer, Nina N.; Gallo, Richard L.

    2016-01-01

    An abundant and diverse collection of bacteria, fungi and viruses inhabit the human skin. These microorganisms have been reported to vary between individuals and between different sites on the skin. The factors responsible for the unique variability of the skin microbiome are only partially understood, but results suggest host genetic and environmental influences play a major role. Today, the steady accumulation of data describing the skin microbiome, combined with experiments designed to test the biological functions of surface microbes, have provided new insights into links between human physiology and skin microbiota. This review describes some of the current information regarding the skin microbiome and their impact on human health. Specifically, this review seeks to summarize the present understanding of the function of microbe–host interactions on the skin and highlight some unique features that distinguish skin commensals from pathogenic microbes. PMID:24238601

  18. Role of human skin in the photodecomposition of bilirubin

    PubMed Central

    Kapoor, Chiranjiv L.; Murti, Coimbatore R. Krishna; Bajpai, Prakash C.

    1974-01-01

    1. Human skin epithelium and human skin were found to absorb both free bilirubin and serum-bound bilirubin from an aqueous buffered medium. The serum-bound bilirubin thus absorbed was readily released when human skin epithelium or human skin were transferred to media containing no bilirubin. 2. The Km values for serum-bound bilirubin were 1.8×10−3m and 2.2×10−3m respectively for human skin epithelium and human skin; corresponding Km values for free bilirubin were 3.0×10−4m and 5×10−4m. The Vmax. for bound and free bilirubin was of the same magnitude, the apparent Vmax. being 1.0 and 1.66μmol/g of tissue for human skin epithelium and human skin respectively. 3. When human skin that had acquired a yellow tinge by absorbing bilirubin was incubated in a buffered medium and exposed to a mercury-vapour light, the yellow colour disappeared and decomposition products of bilirubin accumulated in the medium. 4. Experiments with [3H]bilirubin indicated that the pigment absorbed by skin was photo-oxidized to products that were soluble in water and the quantity and number of such products increased with the time of exposure of human skin to the light-source. Under similar conditions [3H]bilirubin alone in buffered medium was also oxidized and gave products which by paper chromatography appeared to be different from those released by human skin that had absorbed bilirubin. 5. The results suggest that by virtue of its large surface area human skin can act as a matrix for the degradative action of light on bilirubin. PMID:4464841

  19. Permeation Studies of Captopril Transdermal Films Through Human Cadaver Skin.

    PubMed

    Nair, Rajesh Sreedharan; Nair, Sujith

    2015-01-01

    Mortality rate due to heart diseases increases dramatically with age. Captopril is an angiotensin converting enzyme inhibitor (ACE) used effectively for the management of hypertension. Due to short elimination half-life of captopril the oral dose is very high. Captopril is prone to oxidation and it has been reported that the oxidation rate of captopril in skin tissues is considerably low when compared to intestinal tissues. All these factors make captopril an ideal drug candidate for transdermal delivery. In this research work an effort was made to formulate transdermal films of captopril by utilizing polyvinylpyrrolidone (PVP) and polyvinyl alcohol (PVA) as film formers and polyethylene glycol 400 (PEG400) as a plasticizer. Dimethyl sulfoxide (DMSO) and dimethylformamide (DMF) were used as permeation enhancers. Physicochemical parameters of the films such as appearance, thickness, weight variation and drug content were evaluated. The invitro permeation studies were carried out through excised human cadaver skin using Franz diffusion cells. The in-vitro permeation studies demonstrated that the film (P4) having the polymer ratio (PVP:PVA = 80:20) with DMSO (10%) resulted a promising drug release of 79.58% at 24 hours with a flux of 70.0 µg/cm(2)/hr. No signs of erythema or oedema were observed on the rabbit skin as a result of skin irritation study by Draize test. Based on the stability report it was confirmed that the films were physically and chemically stable, hence the prepared films are very well suited for transdermal application.

  20. Comparison of human and porcine skin for characterization of sunscreens

    NASA Astrophysics Data System (ADS)

    Weigmann, Hans-Jürgen; Schanzer, Sabine; Patzelt, Alexa; Bahaban, Virginie; Durat, Fabienne; Sterry, Wolfram; Lademann, Jürgen

    2009-03-01

    The universal sun protection factor (USPF) characterizing sunscreen efficacy based on spectroscopically determined data, which were obtained using the tape stripping procedure. The USPF takes into account the complete ultraviolet (UV) spectral range in contrast to the classical sun protection factor (SPF). Until now, the USPF determination has been evaluated only in human skin. However, investigating new filters not yet licensed excludes in vivo investigation on human skin but requires the utilization of a suitable skin model. The penetration behavior and the protection efficacy of 10 commercial sunscreens characterized by USPF were investigated, comparing human and porcine skin. The penetration behavior found for typical UV filter substances is nearly identical for both skin types. The comparison of the USPF obtained for human and porcine skin results in a linear relation between both USPF values with a correlation factor R2=0.98. The results demonstrate the possibility for the use of porcine skin to determine the protection efficacy of sunscreens.

  1. First genomic survey of human skin fungal diversity

    Cancer.gov

    Fungal infections of the skin affect 29 million people in the United States. In the first study of human fungal skin diversity, National Institutes of Health researchers sequenced the DNA of fungi that thrive at different skin sites of healthy adults to d

  2. DNA repair responses in human skin cells

    SciTech Connect

    Hanawalt, P.C.; Liu, S.C.; Parsons, C.S.

    1981-07-01

    Sunlight and some environmental chemical agents produce lesions in the DNA of human skin cells that if unrepaired may interfere with normal functioning of these cells. The most serious outcome of such interactions may be malignancy. It is therefore important to develop an understanding of mechanisms by which the lesions may be repaired or tolerated without deleterious consequences. Our models for the molecular processing of damaged DNA have been derived largely from the study of bacterial systems. Some similarities but significant differences are revealed when human cell responses are tested against these models. It is also of importance to learn DNA repair responses of epidermal keratinocytes for comparison with the more extensive studies that have been carried out with dermal fibroblasts. Our experimental results thus far indicate similarities for the excision-repair of ultraviolet-induced pyrimidine dimers in human keratinocytes and fibroblasts. Both the monoadducts and the interstrand crosslinks produced in DNA by photoactivated 8-methoxypsoralen (PUVA) can be repaired in normal human fibroblasts but not in those from xeroderma pigmentosum patients. The monoadducts, like pyrimidine dimers, are probably the more mutagenic/carcinogenic lesions while the crosslinks are less easily repaired and probably result in more effective blocking of DNA function. It is suggested that a split-dose protocol that maximizes the production of crosslinks while minimizing the yield of monoadducts may be more effective and potentially less carcinogenic than the single ultraviolet exposure regimen in PUVA therapy for psoriasis.

  3. Skin aging in patients with acquired immunodeficiency syndrome.

    PubMed

    de Aquino Favarato, Grace Kelly Naves; da Silva, Aline Cristina Souza; Oliveira, Lívia Ferreira; da Fonseca Ferraz, Mara Lúcia; de Paula Antunes Teixeira, Vicente; Cavellani, Camila Lourencini

    2016-10-01

    To evaluate the histomorphometric skin changes over aging patients with autopsied acquired immunodeficiency syndrome (AIDS). In 29 skin fragments of autopsied elderly (older than 50 years) and nonelderly patients with AIDS, epidermal thickness, the number of layers, the diameter of cells, the percentage of collagen and elastic fibers in the dermis, and the number and morphology of Langerhans cells were assessed. Statistical analysis was performed by SigmaStat 2.03 program. The thickness of the epidermis (92.55 × 158.94 μm), the number of layers (7 × 9 layers), and the diameter of the cells (13.27 × 17.6 μm) were statistically lower among the elderly. The quantity of collagen fibers (9.68 × 14.11%) and elastic fibers (11.89 × 15.31%) was also significantly lower in the elderly. There was a decrease in total (10.61 × 12.38 cel/mm(2)) and an increase in immature Langerhans cells (6.31 × 4.98 cel/mm(2)) in elderly patients with AIDS. The aging of the skin of patients with AIDS is amended in different histomorphometric aspects, the epidermis constituents suffer less pronounced changes in normal aging, and the dermis has more intense changes in elastic fibers and collagen.

  4. Photoprotection by pistachio bioactives in a 3-dimensional human skin equivalent tissue model.

    PubMed

    Chen, C-Y Oliver; Smith, Avi; Liu, Yuntao; Du, Peng; Blumberg, Jeffrey B; Garlick, Jonathan

    2017-01-25

    Reactive oxygen species (ROS) generated during ultraviolet (UV) light exposure can induce skin damage and aging. Antioxidants can provide protection against oxidative injury to skin via "quenching" ROS. Using a validated 3-dimensional (3D) human skin equivalent (HSE) tissue model that closely mimics human skin, we examined whether pistachio antioxidants could protect HSE against UVA-induced damage. Lutein and γ-tocopherol are the predominant lipophilic antioxidants in pistachios; treatment with these compounds prior to UVA exposure protected against morphological changes to the epithelial and connective tissue compartments of HSE. Pistachio antioxidants preserved overall skin thickness and organization, as well as fibroblast morphology, in HSE exposed to UVA irradiation. However, this protection was not substantiated by the analysis of the proliferation of keratinocytes and apoptosis of fibroblasts. Additional studies are warranted to elucidate the basis of these discordant results and extend research into the potential role of pistachio bioactives promoting skin health.

  5. Setup for investigating gold nanoparticle penetration through reconstructed skin and comparison to published human skin data

    NASA Astrophysics Data System (ADS)

    Labouta, Hagar I.; Thude, Sibylle; Schneider, Marc

    2013-06-01

    Owing to the limited source of human skin (HS) and the ethical restrictions of using animals in experiments, in vitro skin equivalents are a possible alternative for conducting particle penetration experiments. The conditions for conducting penetration experiments with model particles, 15-nm gold nanoparticles (AuNP), through nonsealed skin equivalents are described for the first time. These conditions include experimental setup, sterility conditions, effective applied dose determination, skin sectioning, and skin integrity check. Penetration at different exposure times (two and 24 h) and after tissue fixation (fixed versus unfixed skin) are examined to establish a benchmark in comparison to HS in an attempt to get similar results to HS experiments presented earlier. Multiphoton microscopy is used to detect gold luminescence in skin sections. λex=800 nm is used for excitation of AuNP and skin samples, allowing us to determine a relative index for particle penetration. Despite the observed overpredictability of penetration into skin equivalents, they could serve as a first fast screen for testing the behavior of nanoparticles and extrapolate their penetration behavior into HS. Further investigations are required to test a wide range of particles of different physicochemical properties to validate the skin equivalent-human skin particle penetration relationship.

  6. In vivo multiphoton tomography in skin aging studies

    NASA Astrophysics Data System (ADS)

    König, Karsten; Bückle, Rainer; Weinigel, Martin; Köhler, Johannes; Elsner, Peter; Kaatz, Martin

    2009-02-01

    High-resolution clinical multiphoton tomography based on the femtosecond laser system DermaInspect has been performed on hundreds of patients and volunteers in Australia, Asia, and Europe. The system enables the in vivo detection of the elastin and the collagen network as well as the imaging of melanin clusters in aging spots. The epidermis-dermis junction can be detected with submicron resolution. One major applications of this novel HighTech imaging tool is the determination of the skin aging index SAAID as well as the study of the effects of anti-aging products. In particular, the stimulated biosynthesis of collagen can be investigated over long periods of time. The system with its sub-500 nm lateral resolution is able to image age-related modifications of the extracellular matrix on the level of a single elastin fiber.

  7. In vitro and human testing strategies for skin irritation.

    PubMed

    Robinson, M K; Osborne, R; Perkins, M A

    2000-01-01

    Prior to the manufacture, transport, and marketing of chemicals or products, it is critical to assess their potential for skin toxicity (corrosion or irritation), thereby protecting the worker and consumer from adverse skin effects due to intended or accidental skin exposure. Traditionally, animal testing procedures have provided the data needed to assess the more severe forms of skin toxicity, and current regulations may require animal test data before permission can be obtained to manufacture, transport, or market chemicals or the products that contain them. In recent years, the use of animals to assess skin safety has been opposed by some as inhumane and unnecessary. The conflicting needs of the industrial toxicologist to (1) protect human safety, (2) comply with regulations, and (3) reduce animal testing have led to major efforts to develop alternative, yet predictive, test methods. A variety of in vitro skin corrosion test methods have been developed and several have successfully passed initial international validation. These have included skin or epidermal equivalent assays that have been shown to distinguish corrosive from noncorrosive chemicals. These skin/epidermal equivalent assays have also been modified and used to assess skin irritation potential relative to existing human exposure test data. The data show a good correlation between in vitro assay data and different types of human skin irritation data for both chemicals and consumer products. The effort to eliminate animal tests has also led to the development of a novel human patch test for assessment of acute skin irritation potential. A case study shows the benefits of in vitro and human skin irritation tests compared to the animal tests they seek to replace, and strategies now exist to adequately assess human skin irritation potential without the need to rely on animal test methods.

  8. Molecular cartography of the human skin surface in 3D.

    PubMed

    Bouslimani, Amina; Porto, Carla; Rath, Christopher M; Wang, Mingxun; Guo, Yurong; Gonzalez, Antonio; Berg-Lyon, Donna; Ackermann, Gail; Moeller Christensen, Gitte Julie; Nakatsuji, Teruaki; Zhang, Lingjuan; Borkowski, Andrew W; Meehan, Michael J; Dorrestein, Kathleen; Gallo, Richard L; Bandeira, Nuno; Knight, Rob; Alexandrov, Theodore; Dorrestein, Pieter C

    2015-04-28

    The human skin is an organ with a surface area of 1.5-2 m(2) that provides our interface with the environment. The molecular composition of this organ is derived from host cells, microbiota, and external molecules. The chemical makeup of the skin surface is largely undefined. Here we advance the technologies needed to explore the topographical distribution of skin molecules, using 3D mapping of mass spectrometry data and microbial 16S rRNA amplicon sequences. Our 3D maps reveal that the molecular composition of skin has diverse distributions and that the composition is defined not only by skin cells and microbes but also by our daily routines, including the application of hygiene products. The technological development of these maps lays a foundation for studying the spatial relationships of human skin with hygiene, the microbiota, and environment, with potential for developing predictive models of skin phenotypes tailored to individual health.

  9. Molecular cartography of the human skin surface in 3D

    PubMed Central

    Bouslimani, Amina; Porto, Carla; Rath, Christopher M.; Wang, Mingxun; Guo, Yurong; Gonzalez, Antonio; Berg-Lyon, Donna; Ackermann, Gail; Moeller Christensen, Gitte Julie; Nakatsuji, Teruaki; Zhang, Lingjuan; Borkowski, Andrew W.; Meehan, Michael J.; Dorrestein, Kathleen; Gallo, Richard L.; Bandeira, Nuno; Knight, Rob; Alexandrov, Theodore; Dorrestein, Pieter C.

    2015-01-01

    The human skin is an organ with a surface area of 1.5–2 m2 that provides our interface with the environment. The molecular composition of this organ is derived from host cells, microbiota, and external molecules. The chemical makeup of the skin surface is largely undefined. Here we advance the technologies needed to explore the topographical distribution of skin molecules, using 3D mapping of mass spectrometry data and microbial 16S rRNA amplicon sequences. Our 3D maps reveal that the molecular composition of skin has diverse distributions and that the composition is defined not only by skin cells and microbes but also by our daily routines, including the application of hygiene products. The technological development of these maps lays a foundation for studying the spatial relationships of human skin with hygiene, the microbiota, and environment, with potential for developing predictive models of skin phenotypes tailored to individual health. PMID:25825778

  10. Langerhans cell precursors acquire RANK/CD265 in prenatal human skin.

    PubMed

    Schöppl, Alice; Botta, Albert; Prior, Marion; Akgün, Johnnie; Schuster, Christopher; Elbe-Bürger, Adelheid

    2015-01-01

    The skin is the first barrier against foreign pathogens and the prenatal formation of a strong network of various innate and adaptive cells is required to protect the newborn from perinatal infections. While many studies about the immune system in healthy and diseased adult human skin exist, our knowledge about the cutaneous prenatal/developing immune system and especially about the phenotype and function of antigen-presenting cells such as epidermal Langerhans cells (LCs) in human skin is still scarce. It has been shown previously that LCs in healthy adult human skin express receptor activator of NF-κB (RANK), an important molecule prolonging their survival. In this study, we investigated at which developmental stage LCs acquire this important molecule. Immunofluorescence double-labeling of cryostat sections revealed that LC precursors in prenatal human skin either do not yet [10-11 weeks of estimated gestational age (EGA)] or only faintly (13-15 weeks EGA) express RANK. LCs express RANK at levels comparable to adult LCs by the end of the second trimester. Comparable with adult skin, dermal antigen-presenting cells at no gestational age express this marker. These findings indicate that epidermal leukocytes gradually acquire RANK during gestation - a phenomenon previously observed also for other markers on LCs in prenatal human skin.

  11. In vivo multiphoton microscopy associated to 3D image processing for human skin characterization

    NASA Astrophysics Data System (ADS)

    Baldeweck, T.; Tancrède, E.; Dokladal, P.; Koudoro, S.; Morard, V.; Meyer, F.; Decencière, E.; Pena, A.-M.

    2012-03-01

    Multiphoton microscopy has emerged in the past decade as a promising non-invasive skin imaging technique. The aim of this study was to assess whether multiphoton microscopy coupled to specific 3D image processing tools could provide new insights into the organization of different skin components and their age-related changes. For that purpose, we performed a clinical trial on 15 young and 15 aged human female volunteers on the ventral and dorsal side of the forearm using the DermaInspectR medical imaging device. We visualized the skin by taking advantage of intrinsic multiphoton signals from cells, elastic and collagen fibers. We also developed 3D image processing algorithms adapted to in vivo multiphoton images of human skin in order to extract quantitative parameters in each layer of the skin (epidermis and superficial dermis). The results show that in vivo multiphoton microscopy is able to evidence several skin alterations due to skin aging: morphological changes in the epidermis and modifications in the quantity and organization of the collagen and elastic fibers network. In conclusion, the association of multiphoton microscopy with specific image processing allows the three-dimensional organization of skin components to be visualized and quantified thus providing a powerful tool for cosmetic and dermatological investigations.

  12. Solar ultraviolet irradiation induces decorin degradation in human skin likely via neutrophil elastase.

    PubMed

    Li, Yong; Xia, Wei; Liu, Ying; Remmer, Henriette A; Voorhees, John; Fisher, Gary J

    2013-01-01

    Exposure of human skin to solar ultraviolet (UV) irradiation induces matrix metalloproteinase-1 (MMP-1) activity, which degrades type I collagen fibrils. Type I collagen is the most abundant protein in skin and constitutes the majority of skin connective tissue (dermis). Degradation of collagen fibrils impairs the structure and function of skin that characterize skin aging. Decorin is the predominant proteoglycan in human dermis. In model systems, decorin binds to and protects type I collagen fibrils from proteolytic degradation by enzymes such as MMP-1. Little is known regarding alterations of decorin in response to UV irradiation. We found that solar-simulated UV irradiation of human skin in vivo stimulated substantial decorin degradation, with kinetics similar to infiltration of polymorphonuclear (PMN) cells. Proteases that were released from isolated PMN cells degraded decorin in vitro. A highly selective inhibitor of neutrophil elastase blocked decorin breakdown by proteases released from PMN cells. Furthermore, purified neutrophil elastase cleaved decorin in vitro and generated fragments with similar molecular weights as those resulting from protease activity released from PMN cells, and as observed in UV-irradiated human skin. Cleavage of decorin by neutrophil elastase significantly augmented fragmentation of type I collagen fibrils by MMP-1. Taken together, these data indicate that PMN cell proteases, especially neutrophil elastase, degrade decorin, and this degradation renders collagen fibrils more susceptible to MMP-1 cleavage. These data identify decorin degradation and neutrophil elastase as potential therapeutic targets for mitigating sun exposure-induced collagen fibril degradation in human skin.

  13. Advanced haptic sensor for measuring human skin conditions

    NASA Astrophysics Data System (ADS)

    Tsuchimi, Daisuke; Okuyama, Takeshi; Tanaka, Mami

    2009-12-01

    This paper is concerned with the development of a tactile sensor using PVDF (Polyvinylidene Fluoride) film as a sensory receptor of the sensor to evaluate softness, smoothness, and stickiness of human skin. Tactile sense is the most important sense in the sensation receptor of the human body along with eyesight, and we can examine skin condition quickly using these sense. But, its subjectivity and ambiguity make it difficult to quantify skin conditions. Therefore, development of measurement device which can evaluate skin conditions easily and objectively is demanded by dermatologists, cosmetic industries, and so on. In this paper, an advanced haptic sensor system that can measure multiple information of skin condition in various parts of human body is developed. The applications of the sensor system to evaluate softness, smoothness, and stickiness of skin are investigated through two experiments.

  14. Advanced haptic sensor for measuring human skin conditions

    NASA Astrophysics Data System (ADS)

    Tsuchimi, Daisuke; Okuyama, Takeshi; Tanaka, Mami

    2010-01-01

    This paper is concerned with the development of a tactile sensor using PVDF (Polyvinylidene Fluoride) film as a sensory receptor of the sensor to evaluate softness, smoothness, and stickiness of human skin. Tactile sense is the most important sense in the sensation receptor of the human body along with eyesight, and we can examine skin condition quickly using these sense. But, its subjectivity and ambiguity make it difficult to quantify skin conditions. Therefore, development of measurement device which can evaluate skin conditions easily and objectively is demanded by dermatologists, cosmetic industries, and so on. In this paper, an advanced haptic sensor system that can measure multiple information of skin condition in various parts of human body is developed. The applications of the sensor system to evaluate softness, smoothness, and stickiness of skin are investigated through two experiments.

  15. Lysyl oxidase activity in human normal skins and postburn scars.

    PubMed

    Hayakawa, T; Hino, N; Fuyamada, H; Nagatsu, T; Aoyama, H

    1976-09-06

    Lysyl oxidase activity of human normal skins derived from the frontal thighs of 33 subjects showed large variations and the mean value was 11 455 +/- 7 172 (S.D.) cpm/g of wet weight tissue. The age of lesion affected the lysyl oxidase activity in postburn scars. Granulation tissues showed a fairly low activity; however, the activity increased sharply within 2--3 months, and reached a significantly higher value than that of normal skin. The high level of activity continued for up to 2--3 years, then gradually decreased to normal range after 5 years or so. Lysyl oxidase activity was detected only after 4 M urea treatment of tissues. Benzylamine oxidase activity also showed large variations in both normal skins and postburn scars, with mean values of: 0.128 +/- 0.077 (S.D.) and 0.145 +/- 0.090 (S.D.) mmol/g of wet weight/h, respectively. No correlation was observed between lysyl oxidase and benzylamine oxidase activities. The granulation tissues showed significantly high values of benzylamine oxidase activity in contrast to the low values of lysyl oxidase activity.

  16. Morphine metabolism in human skin microsomes.

    PubMed

    Heilmann, S; Küchler, S; Schäfer-Korting, M

    2012-01-01

    For patients with severe skin wounds, topically applied morphine is an option to induce efficient analgesia due to the presence of opioid receptors in the skin. However, for topical administration it is important to know whether the substance is biotransformed in the skin as this can eventually reduce the concentration of the active agent considerably. We use skin microsomes to elucidate the impact of skin metabolism on the activity of topically applied morphine. We are able to demonstrate that morphine is only glucuronidated in traces, indicating that the biotransformation in the skin can be neglected when morphine is applied topically. Hence, there is no need to take biotransformation into account when setting up the treatment regimen.

  17. Reactive molecule species and antioxidative mechanisms in normal skin and skin aging.

    PubMed

    Wölfle, Ute; Seelinger, Günter; Bauer, Georg; Meinke, Martina C; Lademann, Jürgen; Schempp, Christoph M

    2014-01-01

    Reactive oxygen and nitrogen species (ROS/RNS) which may exist as radicals or nonradicals, as well as reactive sulfur species and reactive carbon species, play a major role in aging processes and in carcinogenesis. These reactive molecule species (RMS), often referred to as 'free radicals' or oxidants, are partly by-products of the physiological metabolism. When RMS concentrations exceed a certain threshold, cell compartments and cells are injured and destroyed. Endogenous physiological mechanisms are able to neutralize RMS to some extent, thereby limiting damage. In the skin, however, pollutants and particularly UV irradiation are able to produce additional oxidants which overload the endogenous protection system and cause early aging, debilitation of immune functions, and skin cancer. The application of antioxidants from various sources in skin care products and food supplements is therefore widespread, with increasingly effective formulations being introduced. The harmful effects of RMS (aside from impaired structure and function of DNA, proteins, and lipids) are: interference with specific regulatory mechanisms and signaling pathways in cell metabolism, resulting in chronic inflammation, weakening of immune functions, and degradation of tissue. Important control mechanisms are: MAP-kinases, the aryl-hydrocarbon receptor (AhR), the antagonistic transcription factors nuclear factor-κB and Nrf2 (nuclear factor erythroid 2-related factor 2), and, especially important, the induction of matrix metalloproteinases which degrade dermal connective tissue. Recent research, however, has revealed that RMS and in particular ROS/RNS are apparently also produced by specific enzyme reactions in an evolutionarily adapted manner. They may fulfill important physiologic functions such as the activation of specific signaling chains in the cell metabolism, defense against infectious pathogens, and regulation of the immune system. Normal physiological conditions are characterized by

  18. Microneedle delivery of plasmid DNA to living human skin: formulation coating, skin insertion and gene expression

    PubMed Central

    Pearton, Marc; Saller, Verena; Coulman, Sion A; Gateley, Chris; Anstey, Alexander V; Zarnitsyn, Vladimir; Birchall, James C

    2012-01-01

    Microneedle delivery of nucleic acids, in particular plasmid DNA (pDNA), to the skin represents a potential new approach for the clinical management of genetic skin diseases and cutaneous cancers, and for intracutaneous genetic immunization. In this study excised human skin explants were used to investigate and optimize key parameters that will determine stable and effective microneedle-facilitated pDNA delivery. These include (i) high dose-loading of pDNA onto microneedle surfaces, (ii) stability and functionality of the coated pDNA, (iii) skin penetration capability of pDNA-coated microneedles, and (iv) efficient gene expression in human skin. Optimization of a dip-coating method enabled significant increases in the loading capacity, up to 100 micrograms of pDNA per 5-microneedle array. Coated microneedles were able to reproducibly perforate human skin at low (<1 Newton) insertion forces. The physical stability of the coated pDNA was partially compromised on storage, although this was improved through the addition of saccharide excipients without detriment to the biological functionality of pDNA. The pDNA-coated microneedles facilitated reporter gene expression in viable human skin. The efficiency of gene expression from coated microneedles will depend upon suitable DNA loading, efficient and reproducible skin puncture and rapid in situ dissolution of the plasmid at the site of delivery. PMID:22516089

  19. New look at the role of progerin in skin aging

    PubMed Central

    Budzisz, Elżbieta; Dana, Agnieszka; Rotsztejn, Helena

    2015-01-01

    Current literature data indicate that progerin, which is a mutant of lamin A, may be one of several previously known physiological biomarkers of the aging process which begins at the age of 30. Lamins belong to the family of intermediate filaments type V and are an important component of the nuclear envelope (NE). The physiological processes of an alternative splicing of LMNA (lamin A/C) gene and posttranslational processing result in the formation of different variants of this gene. Prelamin A is generated in cytosol and modified by respective enzymes. In the final step, 15-aa peptide is released at the C-terminus, resulting in mature lamin A. Point mutation of cytosine to thymine at position 1824 in exon 11 of LMNA gene causes a truncated form of lamin A, which is defined as progerin. In the course of time, progerin is mainly found in skin fibroblasts and reticular layers of terminally differentiated keratinocytes. Changes take place in the nucleus and they are similar to those observed in patients with Hutchinson-Gilford progeria syndrome and refer mainly to an increase in the amount of reactive oxygen species which reduce the level of antioxidant enzymes, DNA damage and histone modification. There are still pending studies on working out new anti-aging strategies and the skin is the main area of research. Biomimetic peptides (analogues of elafin) are used in cosmetics to reduce the formation of progerin. PMID:26327889

  20. Activation of Peroxisome Proliferator-Activated Receptor Alpha Improves Aged and UV-Irradiated Skin by Catalase Induction

    PubMed Central

    Shin, Mi Hee; Lee, Se-Rah; Kim, Min-Kyoung; Shin, Chang-Yup

    2016-01-01

    Peroxisome proliferator-activated receptor alpha (PPARα) is a nuclear hormone receptor involved in the transcriptional regulation of lipid metabolism, fatty acid oxidation, and glucose homeostasis. Its activation stimulates antioxidant enzymes such as catalase, whose expression is decreased in aged human skin. Here we investigated the expression of PPARα in aged and ultraviolet (UV)-irradiated skin, and whether PPARα activation can modulate expressions of matrix metalloproteinase (MMP)-1 and procollagen through catalase regulation. We found that PPARα mRNA level was significantly decreased in intrinsically aged and photoaged human skin as well as in UV-irradiated skin. A PPARα activator, Wy14643, inhibited UV-induced increase of MMP-1 and decrease of procollagen expression and caused marked increase in catalase expression. Furthermore, production of reactive oxygen species (ROS) was suppressed by Wy14643 in UV-irradiated and aged dermal fibroblasts, suggesting that the PPARα activation-induced upregulation of catalase leads to scavenging of ROS produced due to UV irradiation or aging. PPARα knockdown decreased catalase expression and abolished the beneficial effects of Wy14643. Topical application of Wy14643 on hairless mice restored catalase activity and prevented MMP-13 and inflammatory responses in skin. Our findings indicate that PPARα activation triggers catalase expression and ROS scavenging, thereby protecting skin from UV-induced damage and intrinsic aging. PMID:27611371

  1. Stem cells and aberrant signaling of molecular systems in skin aging.

    PubMed

    Peng, Yan; Xuan, Min; Leung, Victor Y L; Cheng, Biao

    2015-01-01

    The skin is the body's largest organ and it is able to self-repair throughout an individual's life. With advanced age, skin is prone to degenerate in response to damage. Although cosmetic surgery has been widely adopted to rejuvinate skin, we are far from a clear understanding of the mechanisms responsible for skin aging. Recently, adult skin-resident stem/progenitor cells, growth arrest, senescence or apoptotic death and dysfunction caused by alterations in key signaling genes, such as Ras/Raf/MEK/ERK, PI3K/Akt-kinases, Wnt, p21 and p53, have been shown to play a vital role in skin regeneration. Simultaneously, enhanced telomere attrition, hormone exhaustion, oxidative stress, genetic events and ultraviolet radiation exposure that result in severe DNA damage, genomic instability and epigenetic mutations also contribute to skin aging. Therefore, cell replacement and targeting of the molecular systems found in skin hold great promise for controlling or even curing skin aging.

  2. Evidence for a physiological role of intracellularly occurring photolabile nitrogen oxides in human skin fibroblasts.

    PubMed

    Opländer, Christian; Wetzel, Wiebke; Cortese, Miriam M; Pallua, Norbert; Suschek, Christoph V

    2008-05-01

    Nitric oxide (NO) plays a pivotal role in human skin biology. Cutaneous NO can be produced enzymatically by NO synthases (NOS) as well as enzyme independently via photodecomposition of photolabile nitrogen oxides (PNOs) such as nitrite or nitroso compounds, both found in human skin tissue in comparably high concentrations. Although the physiological role of NOS-produced NO in human skin is well defined, nothing is known about the biological relevance or the chemical origin of intracellularly occurring PNOs. We here, for the first time, give evidence that in human skin fibroblasts (FB) PNOs represent the oxidation products of NOS-produced NO and that in human skin fibroblasts intracellularly occurring PNOs effectively protect against the injurious effects of UVA radiation by a NO-dependent mechanism. In contrast, in PNO-depleted FB cultures an increased susceptibility to UVA-induced lipid peroxidation and cell death is observed, whereas supplementation of PNO-depleted FB cultures with physiological nitrite concentrations (10 microM) or with exogenously applied NO completely restores UVA-increased injuries. Thus, intracellular PNOs are biologically relevant and represent an important initial shield functioning in human skin physiology against UVA radiation. Consequently, nonphysiological low PNO concentrations might promote known UVA-related skin injuries such as premature aging and carcinogenesis.

  3. Using infrared and Raman microspectroscopies to compare ex vivo involved psoriatic skin with normal human skin.

    PubMed

    Leroy, Marie; Lefèvre, Thierry; Pouliot, Roxane; Auger, Michèle; Laroche, Gaétan

    2015-06-01

    Psoriasis is a chronic dermatosis that affects around 3% of the world's population. The etiology of this autoimmune pathology is not completely understood. The barrier function of psoriatic skin is known to be strongly altered, but the structural modifications at the origin of this dysfunction are not clear. To develop strategies to reduce symptoms of psoriasis or adequate substitutes for modeling, a deep understanding of the organization of psoriatic skin at a molecular level is required. Infrared and Raman microspectroscopies have been used to obtain direct molecular-level information on psoriatic and healthy human skin biopsies. From the intensities and positions of specific vibrational bands, the lipid and protein distribution and the lipid order have been mapped in the different layers of the skin. Results showed a similar distribution of lipids and collagen for normal and psoriatic human skin. However, psoriatic skin is characterized by heterogeneity in lipid/protein composition at the micrometer scale, a reduction in the definition of skin layer boundaries and a decrease in lipid chain order in the stratum corneum as compared to normal skin. A global decrease of the structural organization is exhibited in psoriatic skin that is compatible with an alteration of its barrier properties.

  4. Using infrared and Raman microspectroscopies to compare ex vivo involved psoriatic skin with normal human skin

    NASA Astrophysics Data System (ADS)

    Leroy, Marie; Lefèvre, Thierry; Pouliot, Roxane; Auger, Michèle; Laroche, Gaétan

    2015-06-01

    Psoriasis is a chronic dermatosis that affects around 3% of the world's population. The etiology of this autoimmune pathology is not completely understood. The barrier function of psoriatic skin is known to be strongly altered, but the structural modifications at the origin of this dysfunction are not clear. To develop strategies to reduce symptoms of psoriasis or adequate substitutes for modeling, a deep understanding of the organization of psoriatic skin at a molecular level is required. Infrared and Raman microspectroscopies have been used to obtain direct molecular-level information on psoriatic and healthy human skin biopsies. From the intensities and positions of specific vibrational bands, the lipid and protein distribution and the lipid order have been mapped in the different layers of the skin. Results showed a similar distribution of lipids and collagen for normal and psoriatic human skin. However, psoriatic skin is characterized by heterogeneity in lipid/protein composition at the micrometer scale, a reduction in the definition of skin layer boundaries and a decrease in lipid chain order in the stratum corneum as compared to normal skin. A global decrease of the structural organization is exhibited in psoriatic skin that is compatible with an alteration of its barrier properties.

  5. Comparison of two methods for noninvasive determination of carotenoids in human and animal skin: Raman spectroscopy versus reflection spectroscopy.

    PubMed

    Darvin, Maxim E; Sandhagen, Carl; Koecher, Wolfgang; Sterry, Wolfram; Lademann, Juergen; Meinke, Martina C

    2012-07-01

    Based on compelling in vivo and in vitro studies on human skin, carotenoids are thought to be of great interest as powerful antioxidants acting to prevent free-radical-induced damages, including premature skin ageing and the development of skin diseases such as cancer. Among the available techniques that are suitable for noninvasive determination of carotenoids in human skin, are resonance Raman spectroscopy (RRS) and reflection spectroscopy (RS). For RS, a LED-based miniaturized spectroscopic system (MSS) was developed for noninvasive measurement of carotenoids in human skin. The optimization and subsequent calibration of the MSS was performed with the use of RRS. A strong correlation between the carotenoid concentration determined by the RS and for the RRS system was achieved for human skin in vivo (R = 0.88) and for bovine udder skin in vitro (R = 0.81).

  6. Dermal absorption and skin damage following hydrofluoric acid exposure in an ex vivo human skin model.

    PubMed

    Dennerlein, Kathrin; Kiesewetter, Franklin; Kilo, Sonja; Jäger, Thomas; Göen, Thomas; Korinth, Gintautas; Drexler, Hans

    2016-04-25

    The wide industrial use of hydrofluoric acid (HF) poses a high risk for accidental dermal exposure. Despite local and systemic hazards associated with HF, information on percutaneous penetration and tissue damage is rare. In the present ex vivo study, the dermal absorption of HF (detected in terms of fluoride ions) was quantified and the skin damaging potential as a function of concentration and exposure duration was assessed. Percutaneous penetration of HF (c=5, 30, and 50%) at 3 exposure durations (3, 5, and 10 min) was investigated in a static diffusion cell model using freshly excised human skin. Alterations of skin were histologically evaluated. HF rapidly penetrated through skin under formation of a considerable intradermal reservoir (∼ 13-67% of total absorbed fluoride). Histologically, epidermal alterations were detected already after exposure to 5% HF for 3 min. The degree of skin damage increased with rising concentration and exposure duration leading to coagulation necrosis. For HF concentrations of ≥ 30%, skin damage progressed into deeper skin layers. Topically applied HF concentration was the principal parameter determining HF induced skin effects. The intradermal HF retention capacity associated with progression and prolongation of HF induced skin effects must be considered in the review of skin decontamination procedures.

  7. The role of peroxisome proliferator-activated receptor-coactivator-1 gene in skin aging

    PubMed Central

    Aghaei, Shahrzad; Nilforoushzadeh, Mohammad Ali; Aghaei, Maryam

    2016-01-01

    Skin aging is a continuous process that exhibits fine and deep wrinkles, thin and transparent skin, loss of underlying fat, dry skin and itch, following decreased collagen and elastin synthesis. Both extrinsic and intrinsic agents are considered in the pathogenesis on skin aging. Extrinsic factors such as sun exposure, windy and dry weather, nutrition, and lifestyle may induce premature aging, toxic-free radicals, and reactive oxygen species due to decreasing normal function of mitochondria which play the major intrinsic factors in premature skin aging. One of the major genetic factors in mitochondrial function is peroxisome proliferator-activated receptor-coactivator-1 (PGC-1) gene. This factor could delay skin aging by increasing the mitochondrial biogenesis and replication and oxidative phosphorylation and so may induce free radical scavenging. This review is focused on intrinsic skin aging and the role of PGC-1 protein in decreasing effect of aging causes. PMID:27904582

  8. The immunology of the porcine skin and its value as a model for human skin.

    PubMed

    Summerfield, Artur; Meurens, François; Ricklin, Meret E

    2015-07-01

    The porcine skin has striking similarities to the human skin in terms of general structure, thickness, hair follicle content, pigmentation, collagen and lipid composition. This has been the basis for numerous studies using the pig as a model for wound healing, transdermal delivery, dermal toxicology, radiation and UVB effects. Considering that the skin also represents an immune organ of utmost importance for health, immune cells present in the skin of the pig will be reviewed. The focus of this review is on dendritic cells, which play a central role in the skin immune system as they serve as sentinels in the skin, which offers a large surface area exposed to the environment. Based on a literature review and original data we propose a classification of porcine dendritic cell subsets in the skin corresponding to the subsets described in the human skin. The equivalent of the human CD141(+) DC subset is CD1a(-)CD4(-)CD172a(-)CADM1(high), that of the CD1c(+) subset is CD1a(+)CD4(-)CD172a(+)CADM1(+/low), and porcine plasmacytoid dendritic cells are CD1a(-)CD4(+)CD172a(+)CADM1(-). CD209 and CD14 could represent markers of inflammatory monocyte-derived cells, either dendritic cells or macrophages. Future studies for example using transriptomic analysis of sorted populations are required to confirm the identity of these cells.

  9. Skin permeation and distribution of two sunscreens: a comparison between reconstituted human skin and hairless rat skin.

    PubMed

    Monti, D; Brini, I; Tampucci, S; Chetoni, P; Burgalassi, S; Paganuzzi, D; Ghirardini, A

    2008-01-01

    The aims of this work were (a) to develop a simple and reproducible procedure for percutaneous absorption and distribution tests of sunscreens using one human skin culture model (Epiderm 606; reconstructed epidermis, RE), (b) to compare the said model with rat skin (RS) in vitro and (c) to evaluate the effect of different formulations. The cutaneous permeation and distribution of two UV filters, ethylhexylmethoxycinnamate (MC80) and ethylhexyltriazone (T150), using 3 different vehicles were investigated. The permeation studies demonstrated that neither MC80 nor T150 permeated through both RS and RE in spite of different thicknesses of the 2 substrates. Distribution studies demonstrated that sectioning by cryomicrotome to obtain horizontal skin layers was suitable for both RS and RE (apart from its small thickness) with a good reproducibility of data. The amounts of sunscreens retained in the 2 substrates were in the same order of magnitude for all formulations with a greater depot in RS. Different distribution profiles of the tested formulations could be ascribed to the different lipid compositions of RE and RS. Since the physicochemical characteristics of RE are closer to those of human skin, the results obtained with reconstructed human skin models could be suitable to replace human skin in 'in vitro testing'.

  10. Tactile-direction-sensitive and stretchable electronic skins based on human-skin-inspired interlocked microstructures.

    PubMed

    Park, Jonghwa; Lee, Youngoh; Hong, Jaehyung; Lee, Youngsu; Ha, Minjeong; Jung, Youngdo; Lim, Hyuneui; Kim, Sung Youb; Ko, Hyunhyub

    2014-12-23

    Stretchable electronic skins with multidirectional force-sensing capabilities are of great importance in robotics, prosthetics, and rehabilitation devices. Inspired by the interlocked microstructures found in epidermal-dermal ridges in human skin, piezoresistive interlocked microdome arrays are employed for stress-direction-sensitive, stretchable electronic skins. Here we show that these arrays possess highly sensitive detection capability of various mechanical stimuli including normal, shear, stretching, bending, and twisting forces. Furthermore, the unique geometry of interlocked microdome arrays enables the differentiation of various mechanical stimuli because the arrays exhibit different levels of deformation depending on the direction of applied forces, thus providing different sensory output patterns. In addition, we show that the electronic skins attached on human skin in the arm and wrist areas are able to distinguish various mechanical stimuli applied in different directions and can selectively monitor different intensities and directions of air flows and vibrations.

  11. Skin wound healing in different aged Xenopus laevis.

    PubMed

    Bertolotti, Evelina; Malagoli, Davide; Franchini, Antonella

    2013-08-01

    Xenopus froglets can perfectly heal skin wounds without scarring. To explore whether this capacity is maintained as development proceeds, we examined the cellular responses during the repair of skin injury in 8- and 15-month-old Xenopus laevis. The morphology and sequence of healing phases (i.e., inflammation, new tissue formation, and remodeling) were independent of age, while the timing was delayed in older frogs. At the beginning of postinjury, wound re-epithelialization occurred in form of a thin epithelium followed by a multilayered epidermis containing cells with apoptotic patterns and keratinocytes stained by anti-inducible nitric oxide synthase (iNOS) antibody. The inflammatory response, early activated by recruitment of blood cells immunoreactive to anti-tumor necrosis factor (TNF)-α, iNOS, transforming growth factor (TGF)-β1, and matrix metalloproteinase (MMP)-9, persisted over time. The dermis repaired by a granulation tissue with extensive angiogenesis, inflammatory cells, fibroblasts, and anti-α-SMA positive myofibroblasts. As the healing progressed, wounded areas displayed vascular regression, decrease in cellularity, and rearrangement of provisional matrix. The epidermis restored to a prewound morphology while granulation tissue was replaced by a fibrous tissue in a scar-like pattern. The quantitative PCR analysis demonstrated an up-regulated expression of Xenopus suppressor of cytokine signaling 3 (XSOCS-3) and Xenopus transforming growth factor-β2 (XTGF-β2) soon after wounding and peak levels were detected when granulation tissue was well developed with a large number of inflammatory cells. The findings indicate that X. laevis skin wound healing occurred by a combination of regeneration (in epidermis) and repair (in dermis) and, in contrast to froglet scarless wound healing, the growth to a more mature adult stage is associated with a decrease in regenerative capacity with scar-like tissue formation.

  12. The evolving role of the NAD+/nicotinamide metabolome in skin homeostasis, cellular bioenergetics, and aging.

    PubMed

    Oblong, John E

    2014-11-01

    Human skin is exposed to daily environmental insults, particularly solar radiation, that triggers a range of molecular responses. These perturbations to the normal homeostatic state can lead to cellular dysfunction and, ultimately, impacts tissue integrity and accelerates skin aging (photoaging). One of the responses is increased oxidative stress which has been shown to disrupt cellular bioenergetics. This can be detected by depletion of the nucleotide energy metabolites NAD+ and ATP as both an acute transient decrease and, over time, a more permanent chronic reduction due in part to cumulative damage of mitochondria. NAD+ and its primary precursor nicotinamide have been known for some time to impact skin homeostasis based on linkages to dietary requirements, treatment of various inflammatory conditions, photoaging, and prevention of cancer. Cellular NAD+ pools are known to be lower in aged skin and treatment with nicotinamide is hypothesized to restore these levels, thereby mitigating cellular bioenergetics dysfunction. In dermal fibroblasts, nicotinamide is able to protect against oxidative stress to glycolysis, oxidative phosphorylation as well as increase mitochondrial efficiency via sirtuin-dependent selective mitophagy. Recent research has found that NAD+ cellular pools are more dynamic than previously thought, oscillating in tandem with free nicotinamide, and serves as a regulatory point and feedback loop in cellular metabolism regulation, maintenance of mitochondrial efficiency, and circadian rhythmicity. Since UV-induced oxidative stress in skin can disrupt these processes, continued molecular understanding of the role of NAD+ and nicotinamide in skin biology is important to identify interventions that would help maintain its normal homeostatic functions and efficient cellular bioenergetics.

  13. Identification of Malassezia pachydermatis from healthy and diseased human skin.

    PubMed

    Prohic, Asja; Kasumagic-Halilovic, Emina

    2009-01-01

    Malassezia pachydermatis is the only species in the genus Malassezia that is classically considered to be zoophilic. This yeast is only occasionally isolated from human skin, although it has been found to cause septic epidemics, especially in neonates. The aim of our study was to investigate the prevalence of M. pachydermatis on the skin of patients with Malassezia-associated diseases and of healthy subjects. One hundred and sixty skin scrapings from patients with pityriasis versicolor (PV), seborrhoeic dermatitis (SD), psoriasis (PS) and healthy individuals, forty each, were inoculated into Sabouraud dextrose agar and into modified Dixon agar. The yeasts isolated were identified according to their macroscopic and microscopic features and physiological properties. M. globosa was the most commonly isolated species in lesional skin of PV (65%) and PS (55%), M. restricta in lesional skin of SD (27.5%), while M. sympodialis was the predominant species recovered from healthy skin, representing 30% of the isolates. Zoophilic species, M. pachydermatis was identified in only one case, from the lesional skin of SD. The results of our study confirm that M. pachydermatis is not a member of the normal human flora and its presence on human skin is rare and indicates transmission from an external source.

  14. Quantitative analysis on collagen morphology in aging skin based on multiphoton microscopy

    NASA Astrophysics Data System (ADS)

    Wu, Shulian; Li, Hui; Yang, Hongqin; Zhang, Xiaoman; Li, Zhifang; Xu, Shufei

    2011-04-01

    Multiphoton microscopy was employed for monitoring the structure changes of mouse dermis collagen in the intrinsic- or the extrinsic-age-related processes in vivo. The characteristics of textures in different aging skins were uncovered by fast Fourier transform in which the orientation index and bundle packing of collagen were quantitatively analyzed. Some significant differences in collagen-related changes are found in different aging skins, which can be good indicators for the statuses of aging skins. The results are valuable to the study of aging skin and also of interest to biomedical photonics.

  15. Multifaceted pathways protect human skin from UV radiation.

    PubMed

    Natarajan, Vivek T; Ganju, Parul; Ramkumar, Amrita; Grover, Ritika; Gokhale, Rajesh S

    2014-07-01

    The recurrent interaction of skin with sunlight is an intrinsic constituent of human life, and exhibits both beneficial and detrimental effects. The apparent robust architectural framework of skin conceals remarkable mechanisms that operate at the interface between the surface and environment. In this Review, we discuss three distinct protective mechanisms and response pathways that safeguard skin from deleterious effects of ultraviolet (UV) radiation. The unique stratified epithelial architecture of human skin along with the antioxidant-response pathways constitutes the important defense mechanisms against UV radiation. The intricate pigmentary system and its intersection with the immune-system cytokine axis delicately balance tissue homeostasis. We discuss the relationship among these networks in the context of an unusual depigmenting disorder, vitiligo. The elaborate tunable mechanisms, elegant multilayered architecture and evolutionary selection pressures involved in skin and sunlight interaction makes this a compelling model to understand biological complexity.

  16. Vehicle effects on human stratum corneum absorption and skin penetration.

    PubMed

    Zhang, Alissa; Jung, Eui-Chang; Zhu, Hanjiang; Zou, Ying; Hui, Xiaoying; Maibach, Howard

    2016-07-19

    This study evaluated the effects of three vehicles-ethanol (EtOH), isopropyl alcohol (IPA), and isopropyl myristate (IPM)-on stratum corneum (SC) absorption and diffusion of the [(14)C]-model compounds benzoic acid and butenafine hydrochloride to better understand the transport pathways of chemicals passing through and resident in SC. Following application of topical formulations to human dermatomed skin for 30 min, penetration flux was observed for 24 h post dosing, using an in vitro flow-through skin diffusion system. Skin absorption and penetration was compared to the chemical-SC (intact, delipidized, or SC lipid film) binding levels. A significant vehicle effect was observed for chemical skin penetration and SC absorption. IPA resulted in the greatest levels of intact SC/SC lipid absorption, skin penetration, and total skin absorption/penetration of benzoic acid, followed by IPM and EtOH, respectively. For intact SC absorption and total skin absorption/penetration of butenafine, the vehicle that demonstrated the highest level of sorption/penetration was EtOH, followed by IPA and IPM, respectively. The percent doses of butenafine that were absorbed in SC lipid film and penetrated through skin in 24 h were greatest for IPA, followed by EtOH and IPM, respectively. The vehicle effect was consistent between intact SC absorption and total chemical skin absorption and penetration, as well as SC lipid absorption and chemical penetration through skin, suggesting intercellular transport as a main pathway of skin penetration for model chemicals. These results suggest the potential to predict vehicle effects on skin permeability with simple SC absorption assays. As decontamination was applied 30 min after chemical exposure, significant vehicle effects on chemical SC partitioning and percutaneous penetration also suggest that skin decontamination efficiency is vehicle dependent, and an effective decontamination method should act on chemical solutes in the lipid domain.

  17. Biohydrogels for the In Vitro Re-construction and In Situ Regeneration of Human Skin

    NASA Astrophysics Data System (ADS)

    Korkina, Liudmila; Kostyuk, Vladimir; Guerra, Liliana

    Natural and synthetic biohydrogels are of great interest for the development of innovative medicinal and cosmetic products feasible for the treatment of numerous skin diseases and age-related changes in skin structure and function. Here, the characteristics of bio-resorbable hydrogels as scaffolds for the in vitro re-construction of temporary skin substitutes or full skin equivalents for further transplantation are reviewed. Another fast developing area of regenerative medicine is the in situ regeneration of human skin. The approach is mainly applicable to activate and facilitate the skin regeneration process and angiogenesis in chronic wounds with impaired healing. In this case, extracellular matrix resembling polymers are used to stimulate cell growth, adhesion, and movement. Better results could be achieved by activation of biocompatible hydrogels either with proteins (growth factors, adhesion molecules or/and cytokines) or with allogenic skin cells producing and releasing these molecules. Hydrogels are widely applied as carriers of low molecular weight substances with antioxidant, anti-inflammatory, anti-ageing, and wound healing action. Incorporation of these substances into hydrogels enhances their penetration through the skin barrier and prevents their destruction by oxidation. Potential roles of hydrogel-based products for modern dermatology and cosmetology are also discussed.

  18. Multivariate Models for Prediction of Human Skin Sensitization ...

    EPA Pesticide Factsheets

    One of the lnteragency Coordinating Committee on the Validation of Alternative Method's (ICCVAM) top priorities is the development and evaluation of non-animal approaches to identify potential skin sensitizers. The complexity of biological events necessary to produce skin sensitization suggests that no single alternative method will replace the currently accepted animal tests. ICCVAM is evaluating an integrated approach to testing and assessment based on the adverse outcome pathway for skin sensitization that uses machine learning approaches to predict human skin sensitization hazard. We combined data from three in chemico or in vitro assays - the direct peptide reactivity assay (DPRA), human cell line activation test (h-CLAT) and KeratinoSens TM assay - six physicochemical properties and an in silico read-across prediction of skin sensitization hazard into 12 variable groups. The variable groups were evaluated using two machine learning approaches , logistic regression and support vector machine, to predict human skin sensitization hazard. Models were trained on 72 substances and tested on an external set of 24 substances. The six models (three logistic regression and three support vector machine) with the highest accuracy (92%) used: (1) DPRA, h-CLAT and read-across; (2) DPRA, h-CLAT, read-across and KeratinoSens; or (3) DPRA, h-CLAT, read-across, KeratinoSens and log P. The models performed better at predicting human skin sensitization hazard than the murine

  19. From frog integument to human skin: dermatological perspectives from frog skin biology.

    PubMed

    Haslam, Iain S; Roubos, Eric W; Mangoni, Maria Luisa; Yoshizato, Katsutoshi; Vaudry, Hubert; Kloepper, Jennifer E; Pattwell, David M; Maderson, Paul F A; Paus, Ralf

    2014-08-01

    For over a century, frogs have been studied across various scientific fields, including physiology, embryology, neuroscience, (neuro)endocrinology, ecology, genetics, behavioural science, evolution, drug development, and conservation biology. In some cases, frog skin has proven very successful as a research model, for example aiding in the study of ion transport through tight epithelia, where it has served as a model for the vertebrate distal renal tubule and mammalian epithelia. However, it has rarely been considered in comparative studies involving human skin. Yet, despite certain notable adaptations that have enabled frogs to survive in both aquatic and terrestrial environments, frog skin has many features in common with human skin. Here we present a comprehensive overview of frog (and toad) skin ontogeny, anatomy, cytology, neuroendocrinology and immunology, with special attention to its unique adaptations as well as to its similarities with the mammalian integument, including human skin. We hope to provide a valuable reference point and a source of inspiration for both amphibian investigators and mammalian researchers studying the structural and functional properties of the largest organ of the vertebrate body.

  20. A surrogate for topical delivery in human skin: silicone membranes.

    PubMed

    Sloan, Kenneth B; Synovec, Jennifer; Ketha, Hemamalini

    2013-02-01

    We have identified, for any surrogate membrane and human skin in vitro, the maximum flux through the membrane (output) should be measured if a correlation between the two is to be obtained. We also identified from an analysis of the passive permeation process that molecular weight, lipid and aqueous solubilities (which are easily measured) constitute the physicochemical properties of the active (input), upon which prediction of flux through the surrogate membrane and through skin in vitro should be based. Besides providing the bases for predicting flux, changes in these physicochemical properties can be easily implemented by those wishing to optimize new cosmetics or topical products. Maximum flux values through silicone membrane (n = 70) and through human skin in vitro (n = 52) have been collected and a good correlation between the flux through human skin in vitro and flux through silicone membrane (for the same molecules) was found.

  1. Visible skin colouration predicts perception of male facial age, health and attractiveness.

    PubMed

    Fink, B; Bunse, L; Matts, P J; D'Emiliano, D

    2012-08-01

    Although there is evidence that perception of facial age, health and attractiveness is informed by shape characteristics as well as by visible skin condition, studies on the latter have focused almost exclusively on female skin. Recent research, however, suggests that a decrease in skin colour homogeneity leads to older, less healthy and less attractive ratings of facial skin in both women and men. Here, we elaborate on the significance of the homogeneity of visible skin colouration in men by testing the hypothesis that perception of age, health and attractiveness of (non-contextual) digitally isolated fields of cheek skin only can predict that of whole facial images. Facial digital images of 160 British men (all Caucasian) aged between 10 and 70 were blind-rated for age, health and attractiveness by a total of 147 men and 154 women (mean age = 22.95, SD = 4.26), and these ratings were related to those of corresponding images of cheek skin reported by Fink et al. (J. Eur. Acad. Dermatol. Venereol. in press). Linear regression analysis showed that age, health and attractiveness perception of men's faces could be predicted by the ratings of cheek skin only, such that older men were viewed as older, less healthy and less attractive. This result underlines once again the potent signalling role of skin in its own right, independent of shape or other factors and suggests strongly that visible skin condition, and skin colour homogeneity in particular, plays a significant role in the perception of men's faces.

  2. DNA damage and repair in human skin in situ

    SciTech Connect

    Sutherland, B.M.; Gange, R.W.; Freeman, S.E.; Sutherland, J.C.

    1987-01-01

    Understanding the molecular and cellular origins of sunlight-induced skin cancers in man requires knowledge of the damages inflicted on human skin during sunlight exposure, as well as the ability of cells in skin to repair or circumvent such damage. Although repair has been studied extensively in procaryotic and eucaryotic cells - including human cells in culture - there are important differences between repair by human skin cells in culture and human skin in situ: quantitative differences in rates of repair, as well as qualitative differences, including the presence or absence of repair mechanisms. Quantitation of DNA damage and repair in human skin required the development of new approaches for measuring damage at low levels in nanogram quantities of non-radioactive DNA. The method allows for analysis of multiple samples and the resulting data should be related to behavior of the DNA molecules by analytic expressions. Furthermore, it should be possible to assay a variety of lesions using the same methodology. The development of new analysis methods, new technology, and new biochemical probes for the study of DNA damage and repair are described. 28 refs., 4 figs.

  3. Parabens inhibit human skin estrogen sulfotransferase activity: possible link to paraben estrogenic effects.

    PubMed

    Prusakiewicz, Jeffery J; Harville, Heather M; Zhang, Yanhua; Ackermann, Chrisita; Voorman, Richard L

    2007-04-11

    Parabens (p-hydroxybenzoate esters) are a group of widely used preservatives in topically applied cosmetic and pharmaceutical products. Parabens display weak associations with the estrogen receptors in vitro or in cell based models, but do exhibit estrogenic effects in animal models. It is our hypothesis that parabens exert their estrogenic effects, in part, by elevating levels of estrogens through inhibition of estrogen sulfotransferases (SULTs) in skin. We report here the results of a structure-activity-relationship of parabens as inhibitors of estrogen sulfation in human skin cytosolic fractions and normal human epidermal keratinocytes. Similar to reports of paraben estrogenicity and estrogen receptor affinity, the potency of SULT inhibition increased as the paraben ester chain length increased. Butylparaben was found to be the most potent of the parabens in skin cytosol, yielding an IC(50) value of 37+/-5 microM. Butylparaben blocked the skin cytosol sulfation of estradiol and estrone, but not the androgen dehydroepiandrosterone. The parabens were also tested as inhibitors of SULT activity in a cellular system, with normal human epidermal keratinocytes. The potency of butylparaben increased three-fold in these cells relative to the IC(50) value from skin cytosol. Overall, these results suggest chronic topical application of parabens may lead to prolonged estrogenic effects in skin as a result of inhibition of estrogen sulfotransferase activity. Accordingly, the skin anti-aging benefits of many topical cosmetics and pharmaceuticals could be derived, in part, from the estrogenicity of parabens.

  4. Cohabitation--relationships of corynebacteria and staphylococci on human skin.

    PubMed

    Kwaszewska, Anna; Sobiś-Glinkowska, Maria; Szewczyk, Eligia M

    2014-11-01

    Skin microbiome main cultivable aerobes in human are coagulase-negative staphylococci and lipophilic corynebacteria. Staphylococcus strains (155) belonging to 10 species and 105 strains of Corynebacterium belonging to nine species from the skin swabs of healthy male volunteers were investigated to determine their enzymatic activity to main metabolic substrates: carbohydrates, proteins, lipids, and response to factors present on the skin such as osmotic pressure, pH, and organic acids. The results showed that lipophilic corynebacteria have different capacity for adaptation on the skin than staphylococci. Most of Corynebacterium spp. expressed lack of proteinase, phospholipase, and saccharolytic enzymes activity. Corynebacteria were also more sensitive than Staphylococcus spp. to antimicrobial agents existing on human skin, especially to low pH. These characters can explain domination of Staphylococcus genera on healthy human skin. It can be suggested that within these two bacterial genus, there exists conceivable cooperation and reciprocal protection which results in their quantitative ratio. Such behavior must be considered as crucial for the stability of the population on healthy skin.

  5. 'Skin Trade': Genealogy of Anti-ageing 'Whiteness Therapy' in Colonial Medicine.

    PubMed

    Mire, Amina

    2014-01-01

    This article investigates the extent to which the emerging trend of do-it-yourself anti-ageing skin-whitening products represents a re-articulation of Western colonial concerns with environmental pollution and racial degeneracy into concern with gendered vulnerability. This emerging market is a multibillion dollar industry anchored in the USA, but expanding globally. Do-it-yourself anti-ageing skin-whitening products purport to address the needs of those looking to fight the visible signs of ageing, often promising to remove hyper-pigmented age spots from women's skin, and replace it with ageless skin, free from pigmentation. In order to contextualize the investigation of do-it-yourself anti-ageing skin-whitening practice and discourse, this article draws from the literature in colonial commodity culture, colonial tropical medicine, the contemporary anti-ageing discourse, and advertisements for anti-ageing skin-whitening products. First, it argues that the framing of the biomedicalization of ageing as a pigmentation problem caused by deteriorating environmental conditions and unhealthy lifestyle draws tacitly from European colonial concerns with the European body's susceptibility to tropical diseases, pigmentation disorders, and racial degeneration. Second, the article argues that the rise of do-it-yourself anti-ageing skin-whitening commodities that promise to whiten, brighten, and purify the ageing skin of women and frames the visible signs of ageing in terms of pigmentation pathology.

  6. Gadd45b deficiency promotes premature senescence and skin aging

    PubMed Central

    Magimaidas, Andrew; Madireddi, Priyanka; Maifrede, Silvia; Mukherjee, Kaushiki; Hoffman, Barbara; Liebermann, Dan A.

    2016-01-01

    The GADD45 family of proteins functions as stress sensors in response to various physiological and environmental stressors. Here we show that primary mouse embryo fibroblasts (MEFs) from Gadd45b null mice proliferate slowly, accumulate increased levels of DNA damage, and senesce prematurely. The impaired proliferation and increased senescence in Gadd45b null MEFs is partially reversed by culturing at physiological oxygen levels, indicating that Gadd45b deficiency leads to decreased ability to cope with oxidative stress. Interestingly, Gadd45b null MEFs arrest at the G2/M phase of cell cycle, in contrast to other senescent MEFs, which arrest at G1. FACS analysis of phospho-histone H3 staining showed that Gadd45b null MEFs are arrested in G2 phase rather than M phase. H2O2 and UV irradiation, known to increase oxidative stress, also triggered increased senescence in Gadd45b null MEFs compared to wild type MEFs. In vivo evidence for increased senescence in Gadd45b null mice includes the observation that embryos from Gadd45b null mice exhibit increased senescence staining compared to wild type embryos. Furthermore, it is shown that Gadd45b deficiency promotes senescence and aging phenotypes in mouse skin. Together, these results highlight a novel role for Gadd45b in stress-induced senescence and in tissue aging. PMID:27105496

  7. Gadd45b deficiency promotes premature senescence and skin aging.

    PubMed

    Magimaidas, Andrew; Madireddi, Priyanka; Maifrede, Silvia; Mukherjee, Kaushiki; Hoffman, Barbara; Liebermann, Dan A

    2016-05-10

    The GADD45 family of proteins functions as stress sensors in response to various physiological and environmental stressors. Here we show that primary mouse embryo fibroblasts (MEFs) from Gadd45b null mice proliferate slowly, accumulate increased levels of DNA damage, and senesce prematurely. The impaired proliferation and increased senescence in Gadd45b null MEFs is partially reversed by culturing at physiological oxygen levels, indicating that Gadd45b deficiency leads to decreased ability to cope with oxidative stress. Interestingly, Gadd45b null MEFs arrest at the G2/M phase of cell cycle, in contrast to other senescent MEFs, which arrest at G1. FACS analysis of phospho-histone H3 staining showed that Gadd45b null MEFs are arrested in G2 phase rather than M phase. H2O2 and UV irradiation, known to increase oxidative stress, also triggered increased senescence in Gadd45b null MEFs compared to wild type MEFs. In vivo evidence for increased senescence in Gadd45b null mice includes the observation that embryos from Gadd45b null mice exhibit increased senescence staining compared to wild type embryos. Furthermore, it is shown that Gadd45b deficiency promotes senescence and aging phenotypes in mouse skin. Together, these results highlight a novel role for Gadd45b in stress-induced senescence and in tissue aging.

  8. Reconstructed epidermis versus human and animal skin in skin absorption studies.

    PubMed

    Schreiber, S; Mahmoud, A; Vuia, A; Rübbelke, M K; Schmidt, E; Schaller, M; Kandárová, H; Haberland, A; Schäfer, U F; Bock, U; Korting, H C; Liebsch, M; Schäfer-Korting, M

    2005-09-01

    European chemical policy in general and the REACH initiative in particular will increase the number of chemical substances submitted to toxicological evaluation by several orders of magnitude compared to the current status. To limit animal exposure the resulting enormous increase in testing, however, asks for validated in vitro test systems. While the OECD favours in vitro testing for cutaneous absorption using viable human and animal skin (Guideline 428) the availability of viable human skin is already limited today. We present a comparison of various in vitro techniques suitable for routine skin absorption studies including commercially available reconstructed human epidermis which may be a reliable alternative to excised human and animal skin. In order to develop a protocol for the subsequent transfer to partner laboratories the experimental set-up was analysed stepwise using the OECD reference compounds caffeine and testosterone. Franz cell type, the donor and receptor media for hydrophilic/lipophilic substances, albumin and tensid addition, and storage conditions of the excised skins were systematically varied. A protocol has been developed which now allows to proceed to the pre-validation process.

  9. [The usefulness of protective creams on fragile and aged skin].

    PubMed

    Rueda López, Justo; Guerrero Palmero, Alberto; Muñoz Bueno, Ana Maria; Esquius i Carbonell, Jacint; Rosell Moreno, Carmen

    2005-06-01

    The ADDERMIS protective cream has these properties: it prevents skin maceration, exercises a regenerative effect, has bacteriostatic and bactericide activity, possesses a noted anti-inflammatory effect and reduces the risk of mycotic infections. Its application is indicated for use in cases of: skin lesions, such as bed sores or leg ulcers, which require the use of a barrier product; dermatitis lesions in zones of skin folds or due to diaper use; to prevent friction zones; fragile skin; peeling, zones where cracks in the skin appear...and to use for cases of incontinence when diapers are required.

  10. Cloud-based Monte Carlo modelling of BSSRDF for the rendering of human skin appearance (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Doronin, Alexander; Rushmeier, Holly E.; Meglinski, Igor; Bykov, Alexander V.

    2016-03-01

    We present a new Monte Carlo based approach for the modelling of Bidirectional Scattering-Surface Reflectance Distribution Function (BSSRDF) for accurate rendering of human skin appearance. The variations of both skin tissues structure and the major chromophores are taken into account correspondingly to the different ethnic and age groups. The computational solution utilizes HTML5, accelerated by the graphics processing units (GPUs), and therefore is convenient for the practical use at the most of modern computer-based devices and operating systems. The results of imitation of human skin reflectance spectra, corresponding skin colours and examples of 3D faces rendering are presented and compared with the results of phantom studies.

  11. Human Skin 3D Bioprinting Using Scaffold-Free Approach.

    PubMed

    Pourchet, Léa J; Thepot, Amélie; Albouy, Marion; Courtial, Edwin J; Boher, Aurélie; Blum, Loïc J; Marquette, Christophe A

    2017-02-01

    Organ in vitro synthesis is one of the last bottlenecks between tissue engineering and transplantation of synthetic organs. Bioprinting has proven its capacity to produce 3D objects composed of living cells but highly organized tissues such as full thickness skin (dermis + epidermis) are rarely attained. The focus of the present study is to demonstrate the capability of a newly developed ink formulation and the use of an open source printer, for the production of a really complete skin model. Proofs are given through immunostaining and electronic microscopy that the bioprinted skin presents all characteristics of human skin, both at the molecular and macromolecular level. Finally, the printability of large skin objects is demonstrated with the printing of an adult-size ear.

  12. Metabolism of propranolol during percutaneous absorption in human skin.

    PubMed

    Ademola, J I; Chow, C A; Wester, R C; Maibach, H I

    1993-08-01

    This in vitro study evaluated the extent of the absorption and metabolism of propranolol in human skin from four sources. Between 10.4 +/- 3.1 and 36.6 +/- 2.6% of the applied dose was absorbed; however, only a small portion (between 4.1 +/- 0.9 and 16.1 +/- 1.3%) of the dose permeated through the skin. Naphthoxyacetic acid formed during percutaneous absorption was located in the skin supernate. 4'-Hydroxypropranol was formed during percutaneous absorption and by skin microsomes. In addition, the microsomes biotransformed propranolol to norpropranolol. The retention of some of the absorbed drug and metabolites in the skin could explain the low plasma concentration and irritation observed following topical application of propranolol.

  13. UV radiation induces CXCL5 expression in human skin.

    PubMed

    Reichert, Olga; Kolbe, Ludger; Terstegen, Lara; Staeb, Franz; Wenck, Horst; Schmelz, Martin; Genth, Harald; Kaever, Volkhard; Roggenkamp, Dennis; Neufang, Gitta

    2015-04-01

    CXCL5 has recently been identified as a mediator of UVB-induced pain in rodents. To compare and to extend previous knowledge of cutaneous CXCL5 regulation, we performed a comprehensive study on the effects of UV radiation on CXCL5 regulation in human skin. Our results show a dose-dependent increase in CXCL5 protein in human skin after UV radiation. CXCL5 can be released by different cell types in the skin. We presumed that, in addition to immune cells, non-immune skin cells also contribute to UV-induced increase in CXCL5 protein. Analysis of monocultured dermal fibroblasts and keratinocytes revealed that only fibroblasts but not keratinocytes displayed up regulated CXCL5 levels after UV stimulation. Whereas UV treatment of human skin equivalents, induced epidermal CXCL5 mRNA and protein expression. Up regulation of epidermal CXCL5 was independent of keratinocyte differentiation and keratinocyte-keratinocyte interactions in epidermal layers. Our findings provide first evidence on the release of CXCL5 in UV-radiated human skin and the essential role of fibroblast-keratinocyte interaction in the regulation of epidermal CXCL5.

  14. Thermal conduction effects in human skin.

    PubMed

    Stoll, A M; Chianta, M A; Piergallini, J R

    1979-08-01

    To determine the maximum permissible temperature any material may attain without causing pain or burn on contact with bare skin, over 2000 observations were made of pain threshold during contact with materials at elevated temperatures. Six materials were used representing the full range of thermal properties from good conductors to good insulators. Time to pain threshold was converted to time to threshold blister on the basis of the relationship between pain and burn established earlier for radiant and for convective heating. Calculated times to blister were used to predict the material temperatures causative of "touch-burn". Experimentally produced threshold blisters at the predicted temperature-times verified the predictions. Graphs and equations were generated for determining safe temperatures for any material in contact with bare skin for 1-5 s solely from a knowledge of its thermal properties. Conversely, the thermal inertia (k rho c) of the optimal material for a specific use and skin contact can be predicted from a knowledge of the maximum material temperature and length of contact time anticipated.

  15. Instrumentation for the measurement of autofluorescence in human skin

    NASA Astrophysics Data System (ADS)

    Graaff, Reindert; Meerwaldt, Robbert; Lutgers, Helen L.; Baptist, Rene; de Jong, Ed D.; Zijp, Jaap R.; Links, Thera P.; Smit, Andries J.; Rakhorst, Gerhard

    2005-04-01

    A setup to measure skin autofluorescence was developed to assess accumulation of advanced glycation endproducts (AGE) in patients noninvasively. The method applies direct blacklight tube illumination of the skin of the lower arm, and spectrometry. The setup displays skin autofluorescence (AF) as a ratio of mean intensities detected from the skin between 420-600 nm and 300-420 nm, respectively. In an early clinical application in 46 and control subjects matched for age and gender, AF was significantly increased in the patients (p = 0.015), and highly correlated with skin AGE's that were determined from skin biopsies in both groups. A large follow-up study on type 2 diabetes mellitus, ongoing since 2001 with more than 1000 subjects, aims to assess the value of the instrument in predicting chronic complications of diabetes. At baseline, a relation with age, glycemic status and with complications present was found. In a study in patients with end stage renal disease on dialysis AF was a strong and independent predictor of total and cardiovascular mortality. A commercial version of this AGE-reader is now under development and becomes available early 2005 (DiagnOptics B.V., Groningen, The Netherlands). One of the remaining questions, that will be answered by measuring so-called Exciation-Emission Matrices (EEM's) of the skin tissue in vivo, is whether a more selective choice of wavelengths is more strongly related to clinical characteristics. An experimental instrument to measure these EEM's was, therefore, developed as well. Clinical measurements are underway of EEM's in patient groups with diabetes mellitus and in healthy volunteers.

  16. Skin Anti-Aging Activities of Bacteriochlorophyll a from Photosynthetic Bacteria, Rhodobacter sphaeroides.

    PubMed

    Kim, Nam Young; Yim, Tae Bin; Lee, Hyeon Yong

    2015-10-01

    In this work, the anti-aging skin effects of bacteriochlorophyll a isolated from Rhodobacter sphaeroides are first reported, with notably low cytotoxicity in the range of 1% to 14% in adding 0.00078 (% (w/w)) of the extracts, compared with the normal growth of both human dermal fibroblast and keratinocyte cells without any treatment as a control. The highest production of procollagen from human fibroblast cells (CCD-986sk) was observed as 221.7 ng/ml with 0.001 (% (w/w)) of bacteriochlorophyll a, whereas 150 and 200 ng/ml of procollagen production resulted from addition of 0.001 (% (w/w)) of the photosynthetic bacteria. The bacteriochlorophylla- induced TNF-α production increased to 63.8%, which was lower secretion from HaCaT cells than that from addition of 0.00005 (% (w/w)) of bacteriochlorophyll a. Additionally, bacteriochlorophyll a upregulated the expression of genes related to skin anti-aging (i.e., keratin 10, involucrin, transglutaminase-1, and MMPs), by up to 4-15 times those of the control. However, crude extracts from R. sphaeroides did not enhance the expression level of these genes. Bacteriochlorophyll a showed higher antioxidant activity of 63.8% in DPPH free radical scavenging than those of water, ethanol, and 70% ethanol extracts (14.0%, 57.2%, and 12.6%, respectively). It was also shown that the high antioxidant activity could be attributed to the skin anti-aging effect of bacteriochlorophyll a, although R. sphaeroides itself would not exhibit significant anti-aging activities.

  17. [VISIBLE LIGHT AND HUMAN SKIN (REVIEW)].

    PubMed

    Tsibadze, A; Chikvaidze, E; Katsitadze, A; Kvachadze, I; Tskhvediani, N; Chikviladze, A

    2015-09-01

    Biological effect of a visible light depends on extend of its property to penetrate into the tissues: the greater is a wavelength the more is an effect of a radiation. An impact of a visible light on the skin is evident by wave and quantum effects. Quanta of a visible radiation carry more energy than infrared radiation, although an influence of such radiation on the skin is produced by the light spectrum on the boarder of the ultraviolet and the infrared rays and is manifested by thermal and chemical effects. It is determined that large doses of a visible light (405-436 nm) can cause skin erythema. At this time, the ratio of generation of free radicals in the skin during an exposure to the ultraviolet and the visible light range from 67-33% respectively. Visible rays of 400-500 nm length of wave cause an increase of the concentration of oxygen's active form and mutation of DNA and proteins in the skin. The urticaria in 4-18% of young people induced by photodermatosis is described. As a result of a direct exposure to sunlight photosensitive eczema is more common in elderly. Special place holds a hereditary disease - porphyria, caused by a visible light. In recent years, dermatologists widely use phototherapy. The method uses polychromatic, non-coherent (wavelength of 515-1200 nm) pulsating beam. During phototherapy/light treatment a patient is being exposed to sunlight or bright artificial light. Sources of visible light are lasers, LEDs and fluorescent lamps which have the full range of a visible light. Phototherapy is used in the treatment of acne vulgaris, seasonal affective disorders, depression, psoriasis, eczema and neurodermities. LED of the red and near infrared range also is characterized by the therapeutic effect. They have an ability to influence cromatophores and enhance ATP synthesis in mitochondria. To speed up the healing of wounds and stimulate hair growth light sources of a weak intensity are used. The light of blue-green spectrum is widely used for

  18. Weight-bearing-induced changes in the microtopography and structural stiffness of human skin in vivo following immobility periods.

    PubMed

    Dobos, Gabor; Gefen, Amit; Blume-Peytavi, Ulrike; Kottner, Jan

    2015-01-01

    Pressure ulcers (PUs) are injuries to the skin and underlying tissues, caused by sustained deformations and occur frequently in aged patients. Skin microtopography and stiffness affect the interaction of skin with contact surfaces contributing to PU development. We simulated immobility in 20 healthy females (mean age 69.9 years). Skin microtopography and stiffness were measured at the PU predilection sites before and after loading. Skin roughness decreased at the heels by 18.1% after 90 minutes (p = 0.022), but remained unchanged at the sacrum and the upper back. Structural elasticity and elastic deformations increased at all skin areas; changes over time were significant at the sacrum (p = 0.005) and the heel, (p = 0.002). The residual skin deformation increased at all skin areas after loading significantly at the sacrum (32.0%, p = 0.013) and upper back (20.6%, p = 0.007). The structural "biological" elasticity of the skin decreased significantly at the upper back after loading, but remained unchanged at the heels. All skin changes recovered after unloading. Results indicate that prolonged loading causes structural skin changes in humans in vivo in PU predilection sites. The pathogenesis of PUs is different at the heels, the sacral and upper back skin.

  19. Skin blood perfusion and oxygenation colour affect perceived human health.

    PubMed

    Stephen, Ian D; Coetzee, Vinet; Law Smith, Miriam; Perrett, David I

    2009-01-01

    Skin blood perfusion and oxygenation depends upon cardiovascular, hormonal and circulatory health in humans and provides socio-sexual signals of underlying physiology, dominance and reproductive status in some primates. We allowed participants to manipulate colour calibrated facial photographs along empirically-measured oxygenated and deoxygenated blood colour axes both separately and simultaneously, to optimise healthy appearance. Participants increased skin blood colour, particularly oxygenated, above basal levels to optimise healthy appearance. We show, therefore, that skin blood perfusion and oxygenation influence perceived health in a way that may be important to mate choice.

  20. Fluorescence lifetime imaging of human skin and hair

    NASA Astrophysics Data System (ADS)

    Ehlers, A.; Riemann, I.; Anhut, T.; Kaatz, M.; Elsner, P.; König, K.

    2006-02-01

    Multiphoton imaging has developed into an important technique for in-vivo research in life sciences. With the laser System DermaInspect (JenLab, Germany) laser radiation from a Ti:Sapphire laser is used to generate multiphotonabsorption deep in the human skin in vivo. The resulting autofluorescence radiation arises from endogenous fluorophores such as NAD(P)H, flavines, collagen, elastin, porphyrins und melanin. Second harmonic generation (SHG) was used to detect collagen structures in the dermal layer. Femtosecond laser multiphoton imaging offers the possibility of high resolution optical tomography of human skin as well as fluorescence lifetime imaging (FLIM) with picosecond time resolution. In this work a photon detector with ultrashort rise time of less than 30ps was applied to FLIM measurements of human skin and hair with different pigmentation. Fluorescence lifetime images of different human hair types will be discussed.

  1. Serotoninergic and melatoninergic systems are fully expressed in human skin.

    PubMed

    Slominski, Andrzej; Pisarchik, Alexander; Semak, Igor; Sweatman, Trevor; Wortsman, Jacobo; Szczesniewski, Andre; Slugocki, George; McNulty, John; Kauser, Söbia; Tobin, Desmond J; Jing, Chen; Johansson, Olle

    2002-06-01

    We investigated the cutaneous expression of genes and enzymes responsible for the multistep conversion of tryptophan to serotonin and further to melatonin. Samples tested were human skin, normal and pathologic (basal cell carcinoma and melanoma), cultured normal epidermal and follicular melanocytes, melanoma cell lines, normal neonatal and adult epidermal and follicular keratinocytes, squamous cell carcinoma cells, and fibroblasts from dermis and follicular papilla. The majority of the samples showed simultaneous expression of the genes for tryptophan hydroxylase, arylalkylamine N-acetyltransferase (AANAT), and hydroxyindole-O-methyltransferase (HIOMT). The products of AANAT activity were identified by RP-HPLC with fluorimetric detection in human skin and in cultured normal and malignant melanocytes and immortalized keratinocytes; HIOMT activity was detected in human skin, keratinocytes, and melanoma cells. N-acetylserotonin (NAS) was detected by RP-HPLC in human skin extracts. NAS identity was confirmed further by LC/MS in keratinocytes. In conclusion, we provide evidence that the human skin expresses intrinsic serotonin and melatonin biosynthetic pathways.

  2. Influence of human skin specimens consisting of different skin layers on the result of in vitro permeation experiments.

    PubMed

    Henning, A; Neumann, D; Kostka, K-H; Lehr, C-M; Schaefer, U F

    2008-01-01

    The literature exhibits high variation in results from drug permeation experiments across human skin. Our purpose was to investigate the influence of human skin specimens, consisting of different skin layers and resulting from different skin preparation techniques, on the in vitro permeation of a model drug, i.e. flufenamic acid (FFA). FFA permeation across human (1) trypsin-isolated stratum corneum, (2) heat-separated epidermis and (3) dermis, (4) dermatomized skin and (5) full-thickness skin (FTS) from either a hydrophilic or lipophilic donor was investigated in Franz-type diffusion cells. Cumulative permeated drug amounts were plotted versus time, and a fit to Fick's 2nd law of diffusion was performed. Since performing skin diffusion experiments in the laboratory is time consuming and expensive, especially when using FTS, we also investigated the possibility of calculating the resistances of composite skin layers from the diffusion resistances of the individual skin layers. Due to short lag time, practical handling and economic preparation, heat-separated epidermis appears to be superior in human skin in vitro permeation experiments compared to separated stratumcorneum sheets, dermatomized skin and FTS. Furthermore, we found a good correlation between calculated and experimental resistances which underlines that calculation of the total diffusion resistance of composed skin preparations from resistances of individual skin layers is legitimate and useful. Considering our findings, improved interpretation of literature data and more consistent results for future permeation experiments are possible.

  3. Human skin permeation of emerging mycotoxins (beauvericin and enniatins).

    PubMed

    Taevernier, Lien; Veryser, Lieselotte; Roche, Nathalie; Peremans, Kathelijne; Burvenich, Christian; Delesalle, Catherine; De Spiegeleer, Bart

    2016-01-01

    Currently, dermal exposure data of cyclic depsipeptide mycotoxins are completely absent. There is a lack of understanding about the local skin and systemic kinetics and effects, despite their widespread skin contact and intrinsic hazard. Therefore, we provide a quantitative characterisation of their dermal kinetics. The emerging mycotoxins enniatins (ENNs) and beauvericin (BEA) were used as model compounds and their transdermal kinetics were quantitatively evaluated, using intact and damaged human skin in an in vitro Franz diffusion cell set-up and ultra high-performance liquid chromatography (UHPLC)-MS analytics. We demonstrated that all investigated mycotoxins are able to penetrate through the skin. ENN B showed the highest permeation (kp,v=9.44 × 10(-6) cm/h), whereas BEA showed the lowest (kp,v=2.35 × 10(-6) cm/h) and the other ENNs ranging in between. Combining these values with experimentally determined solubility data, Jmax values ranging from 0.02 to 0.35 μg/(cm(2) h) for intact skin and from 0.07 to 1.11 μg/(cm(2) h) for damaged skin were obtained. These were used to determine the daily dermal exposure (DDE) in a worst-case scenario. On the other hand, DDE's for a typical occupational scenario were calculated based on real-life mycotoxin concentrations for the industrial exposure of food-related workers. In the latter case, for contact with intact human skin, DDE's up to 0.0870 ng/(kg BW × day) for ENN A were calculated, whereas for impaired skin barrier this can even rise up to 0.3209 ng/(kg BW × day) for ENN B1. This knowledge is needed for the risk assessment after skin exposure of contaminated food, feed, indoor surfaces and airborne particles with mycotoxins.

  4. Algorithm for Analyzing Thermal Images of Laser Irradiated Human Skin

    PubMed Central

    Toumi, Johnny; Saiof, Fawaz; Bachir, Wesam

    2016-01-01

    Introduction: Tracking temporal changes of temperature during laser skin treatment plays an important role in improving the process of laser skin treatment itself. There are a number of methods to analyze temperature’s temporal dependency during laser skin treatment; some of those methods depend on imaging the skin with thermal cameras. However, the use of thermal cameras exhibits specific problems, including the ability to track laser-skin interaction spot. This paper is dedicated to solve that problem using digital image processing program coded with Matlab. Methods: The measurements were taken for 15 native Syrian subjects of different sex, age and skin tones, the treated ailment was port wine stain. The clinical work (laser exposure) was performed in Damascus University, hospital of dermatology. The treatment was observed by thermal camera and analyzed using the proposed Matlab coded tracking system. Results: For all the subjects, the treatment laser spot was tracked and the curves of skin temperature change with time where calculated by the use of the proposed algorithm, then the active time was calculated for each subject. The algorithm proved practical and robust. Conclusion: The proposed algorithm proved to be efficient and can be used to support future researchers with capability to measure the temperature with high frame rate. PMID:28144436

  5. Mobile phone radiation might alter protein expression in human skin

    PubMed Central

    Karinen, Anu; Heinävaara, Sirpa; Nylund, Reetta; Leszczynski, Dariusz

    2008-01-01

    Background Earlier we have shown that the mobile phone radiation (radiofrequency modulated electromagnetic fields; RF-EMF) alters protein expression in human endothelial cell line. This does not mean that similar response will take place in human body exposed to this radiation. Therefore, in this pilot human volunteer study, using proteomics approach, we have examined whether a local exposure of human skin to RF-EMF will cause changes in protein expression in living people. Results Small area of forearm's skin in 10 female volunteers was exposed to RF-EMF (specific absorption rate SAR = 1.3 W/kg) and punch biopsies were collected from exposed and non-exposed areas of skin. Proteins extracted from biopsies were separated using 2-DE and protein expression changes were analyzed using PDQuest software. Analysis has identified 8 proteins that were statistically significantly affected (Anova and Wilcoxon tests). Two of the proteins were present in all 10 volunteers. This suggests that protein expression in human skin might be affected by the exposure to RF-EMF. The number of affected proteins was similar to the number of affected proteins observed in our earlier in vitro studies. Conclusion This is the first study showing that molecular level changes might take place in human volunteers in response to exposure to RF-EMF. Our study confirms that proteomics screening approach can identify protein targets of RF-EMF in human volunteers. PMID:18267023

  6. Optical tomography of pigmented human skin biopsies

    NASA Astrophysics Data System (ADS)

    Riemann, Iris; Fischer, Peter; Kaatz, Martin; Fischer, Tobias W.; Elsner, Peter; Dimitrov, Enrico; Reif, Annette; Konig, Karsten

    2004-07-01

    The novel femtosecond NIR (near infrared) laser based high resolution imaging system DermaInspect was used for non-invasive diagnostics of pigmented skin. The system provides fluorescence and SHG images of high spatial submicron resolution (3D) and 250 ps temporal resolution (4D) based on time resolved single photon counting (TCSPC). Pigmented tissue biopsies from patients with nevi and melanoma have been investigated using the tunable 80 MHz femtosecond laser MaiTai with laser wavelengths in the range of 750 - 850 nm. The autofluorescence patterns of different intratissue cell types and structures were determined. The non-linear induced autofluorescence originates from naturally endogenous fluorophores and protein structures like NAD(P)H, flavins, elastin, collagen, phorphyrins and melanin. In addition to autofluorescence, SHG (second harmonic generation) was used to detect dermal collagen structures. Interestingly, pigmented cells showed intense luminescence signals. Further characterization of tissue components was performed via 4D measurements of the fluorescence lifetime (x, y, z, τ). The novel multiphoton technique offers the possibility of a painless high resolution non invasive diagnostic method (optical biopsy), in particular for the early detection of skin cancer.

  7. Anti-Aging Effects of the Hanwoo Leg Bone, Foot and Tail Infusions (HLI, HFI and HTI) on Skin Fibroblast.

    PubMed

    Seol, Ja Young; Yoon, Ji Young; Jeong, Hee Sun; Joo, Nami; Choi, Soon Young

    2016-01-01

    Many researchers revealed that collagen contribute to maintaining the skin's elasticity and inhibit wrinkling of skin. Korean native cattle (Hanwoo) bone (leg bone, foot and tail) infusion contains the various inorganic materials, collagen and chondroitin sulfate. All of this, a large quantity of collagen is included in Hanwoo infusion. Therefore, this study emphasized on the effects of collagen in the Hanwoo bone infusion. For the first time, Hanwoo bone infusions were directly added to the media of Human Dermal Fibroblast (NHDF-c) to test anti-aging effects. First, it was identified that growth rate of skin fibroblast was increased. Furthermore, the Hanwoo bone infusion increased a 50% of fibroblast collagen synthesis. Also, suppression of skin fibroblast aging was confirmed by treatment Hanwoo bone infusion. In conclusion, this study demonstrates the effects of infusion made from Hanwoo leg bone, foot and tail on anti-aging, wrinkle inhibiting and skin fibroblast elasticity maintaining. Therefore, this study identified that traditional infusion has effects that are good for skin elasticity.

  8. Polysaccharide Extracted from Laminaria japonica Delays Intrinsic Skin Aging in Mice

    PubMed Central

    Hu, Longyuan; Tan, Jia; Yang, Xiaomei; Tan, Haitao; Xu, Xiaozhen; You, Manhang; Qin, Wu; Huang, Liangzhao; Li, Siqi; Mo, Manqiu; Wei, Huifen; Li, Jing; Tan, Jiyong

    2016-01-01

    This study aimed to determine the effect of topically applied Laminaria polysaccharide (LP) on skin aging. We applied ointment containing LP (10, 25, and 50 μg/g) or vitamin E (10 μg/g) to the dorsal skin of aging mice for 12 months and young control mice for 4 weeks. Electron microscopy analysis of skin samples revealed that LP increased dermal thickness and skin collagen content. Tissue inhibitor of metalloprotease- (TIMP-) 1 expression was upregulated while that of matrix metalloproteinase- (MMP-) 1 was downregulated in skin tissue of LP-treated as compared to untreated aging mice. Additionally, phosphorylation of c-Jun N-terminal kinase (JNK) and p38 was higher in aging skin than in young skin, while LP treatment suppressed phospho-JNK expression. LP application also enhanced the expression of antioxidative enzymes in skin tissue, causing a decrease in malondialdehyde levels and increases in superoxide dismutase, catalase, and glutathione peroxidase levels relative to those in untreated aging mice. These results indicate that LP inhibits MMP-1 expression by preventing oxidative stress and JNK phosphorylation, thereby delaying skin collagen breakdown during aging. PMID:27143987

  9. Two-wavelength Raman detector for noninvasive measurements of carotenes and lycopene in human skin

    NASA Astrophysics Data System (ADS)

    Ermakov, Igor V.; Ermakova, Maia R.; Gellermann, Werner

    2005-04-01

    Carotenoids are an important part of the antioxidant system in human skin. Carotenoid molecules, provided by fruits and vegetables, are potent free radical quenchers that accumulate in the body. If not balanced by carotenoids and other antioxidants, free radicals may cause premature skin aging, oxidative cell damage, and even skin cancers. As carotenoids depletion may predispose a person to cancer or other disease, rapid and noninvasive measurement of carotenoid level in skin may be of preventive or diagnostic help. At the very least, such measurement can be used to obtain a biomarker for healthy levels of fruit and vegetable consumption. Recently we have developed noninvasive optical technique based on Raman spectroscopy. In this paper we describe compact optical detector for clinical applications that utilizes two-wavelength excitation. It selectively measures the two most prominent skin carotenoids found in the human skin, lycopene and carotenes. According to the medical literature, these two compounds may play different roles in the human body and be part of different tissue defense mechanisms. Dual-wavelength Raman measurements reveal significant differences in the carotenoid composition of different subjects.

  10. The effect of mother-infant skin-to-skin contact on infants' response to the Still Face Task from newborn to three months of age.

    PubMed

    Bigelow, Ann E; Power, Michelle

    2012-04-01

    The effect of mother-infant skin-to-skin contact on infants' developing social expectations for maternal behavior was investigated longitudinally over infants' first 3 months. Infants with and without skin-to-skin contact engaged with their mothers in the Still Face Task at ages 1 week, 1 month, 2 months, and 3 months. Infants with skin-to-skin contact began responding to changes in their mothers' behavior with their affect at 1 month; infants without skin-to-skin contact did so at 2 months. At 3 months, infants with skin-to-skin contact increased their non-distress vocalizations during the still face phase, suggesting social bidding to their mothers. Skin-to-skin contact accelerated infants' social expectations for their mothers' behavior and enhanced infants' awareness of themselves as active agents in social interactions.

  11. Biogeography and individuality shape function in the human skin metagenome.

    PubMed

    Oh, Julia; Byrd, Allyson L; Deming, Clay; Conlan, Sean; Kong, Heidi H; Segre, Julia A

    2014-10-02

    The varied topography of human skin offers a unique opportunity to study how the body's microenvironments influence the functional and taxonomic composition of microbial communities. Phylogenetic marker gene-based studies have identified many bacteria and fungi that colonize distinct skin niches. Here metagenomic analyses of diverse body sites in healthy humans demonstrate that local biogeography and strong individuality define the skin microbiome. We developed a relational analysis of bacterial, fungal and viral communities, which showed not only site specificity but also individual signatures. We further identified strain-level variation of dominant species as heterogeneous and multiphyletic. Reference-free analyses captured the uncharacterized metagenome through the development of a multi-kingdom gene catalogue, which was used to uncover genetic signatures of species lacking reference genomes. This work is foundational for human disease studies investigating inter-kingdom interactions, metabolic changes and strain tracking, and defines the dual influence of biogeography and individuality on microbial composition and function.

  12. Cortisol extraction through human skin by reverse iontophoresis.

    PubMed

    Ventura, Stephanie A; Heikenfeld, Jason; Brooks, Tiffany; Esfandiari, Leyla; Boyce, Steven; Park, Yoonjee; Kasting, Gerald B

    2017-04-01

    Continuous monitoring of cortisol at the surface of the skin would advance the diagnosis and treatment of cortisol-related diseases, or of elevated cortisol levels related to stress in otherwise healthy populations. Reliable and accurate detection of cortisol at the skin surface remains a limiting factor in real-time monitoring of cortisol. To address this limitation, cortisol extraction through excised human skin by reverse iontophoresis was studied in vitro in side-by-side diffusion cells using a radiolabeled probe. The skin was subjected to four direct current regimens (0, 28, 56, 113μAcm(-2)) with the anode in the donor chamber and the cumulative cortisol concentrations recorded in the receiver chamber. The 56 and 113μAcm(-2) regimens significantly increased transport of (3)H-cortisol through the skin, and current density correlated directly with transcutaneous transport of (3)H-cortisol. The threshold of detection of electroosmotic versus passive diffusion of cortisol through the skin was between 28 and 56μAcm(-2). The results of this study are significant in examining how lipophilic analytes found in the bloodstream respond to reverse iontophoresis across the skin. In addition, a device integration technique is presented which illustrates how continuous cortisol extraction and sensing could potentially be achieved in a conventional wearable format.

  13. OCT monitoring of cosmetic creams in human skin in vivo

    NASA Astrophysics Data System (ADS)

    Han, Seung Hee; Yoon, Chang Han; Conroy, Leigh; Vitkin, I. Alex

    2012-02-01

    Optical coherence tomography (OCT) is a tool currently used for noninvasive diagnosis of human disease as well as for monitoring treatment during or after therapy. In this study, OCT was used to examine penetration and accumulation of cosmetic creams on human hand skin. The samples varied in collagen content with one formulation containing soluble collagen as its primary active ingredient. Collagen is a major connective tissue protein that is essential in maintaining health vitality and strength of many organs. The penetration and localization of collagen in cosmetic creams is thought to be the main determinant of the efficacy of new collagen synthesis. Detection and quantification of collagen in cosmetic creams applied to skin may thus help predict the eventual efficacy of the product in skin collagen regeneration. We hypothesize that the topically applied collagen may be detectable by OCT through its modulation of skin scattering properties. To test this hypothesis, we used a FDML swept-source optical coherence tomography (SS-OCT) system. A particular location on the skin of two male adult volunteers was used to investigate 4 different cosmetic creams. The duration of OCT monitoring of cosmetic penetration into skin ranged from 5 minutes to 2 hours following topical application. The results showed that OCT can discriminate between a cream with collagen and other collagen-free formulations. Thus it seems feasible that OCT intensity can monitor the in vivo effects of topical application of collagen contained in cosmetic formulations.

  14. Diversity of human papillomaviruses in skin lesions.

    PubMed

    Ekström, Johanna; Mühr, Laila Sara Arroyo; Bzhalava, Davit; Söderlund-Strand, Anna; Hultin, Emilie; Nordin, Peter; Stenquist, Bo; Paoli, John; Forslund, Ola; Dillner, Joakim

    2013-12-01

    Pools of frozen biopsies from patients with squamous cell carcinoma (SCC) (n=29) actinic keratosis (AK) (n=31), keratoacanthoma (n=91) and swab samples from 84 SCCs and 91 AKs were analysed with an extended HPV general primer PCR and high-throughput sequencing of amplimers. We found 273 different HPV isolates (87 known HPV types, 139 previously known HPV sequences (putative types) and 47 sequences from novel putative HPV types). Among the new sequences, five clustered in genus Betapapillomavirus and 42 in genus Gammapapillomavirus. Resequencing of the three pools between 21 to 70 times resulted in the detection of 283 different known or putative HPV types, with 156 different sequences found in only one of the pools. Type-specific PCRs for 37 putative types from an additional 296 patients found only two of these putative types. In conclusion, skin lesions contain a large diversity of HPV types, but most appeared to be rare infections.

  15. Multiple Skin Cancers in a Renal Transplant Recipient: A Patient Report with Analyses of Human Papillomavirus and Human Polyomavirus Infection

    PubMed Central

    Kaneda, Tokinobu; Matsushita, Michiko; Iwasaki, Takeshi; Ishiguro, Naoko; Koide, Takashi; Hayashi, Kazuhiko; Kitamura, Yukisato

    2015-01-01

    Skin cancer is an important complication in renal transplant recipients. Associations of transplant-related skin tumor with ultraviolet radiation, age at transplantation, type of immunosuppressant drug administered, and viral infection have been reported; however, the details remain unclear. We report a 61-year-old man who had underwent renal transplantation at 38 years of age and developed multiple skin tumors or squamous cell carcinomas (SCCs). Polymerase chain reaction (PCR) analyses of the patient’s 12 tumors for viral DNAs of cutaneous or mucosal human papillomavirus (HPV) and 6 human polyomaviruses (MCPyV, trichodysplasia spinulosa-associated, BK, JC, KI and WU polyomaviruses) only detected cutaneous HPV-DNA in only 5 of the tumors; no other viruses were detected. Real-time PCR showed high loads of cutaneous HPV in 3 SCCs and very low loads of MCPyV in 9. Immunohistochemistry revealed no tumor cell expression for MCPyV-large T-antigen or mucosal HPV. Our report not only reconfirmed the association of cutaneous HPV5 with skin cancer in renal transplant recipients in previous studies but also showed no relevant association of 6 human polyomaviruses and mucosal HPV with skin tumors. PMID:26538801

  16. Current concepts of active vasodilation in human skin

    PubMed Central

    Wong, Brett J.; Hollowed, Casey G.

    2017-01-01

    ABSTRACT In humans, an increase in internal core temperature elicits large increases in skin blood flow and sweating. The increase in skin blood flow serves to transfer heat via convection from the body core to the skin surface while sweating results in evaporative cooling of the skin. Cutaneous vasodilation and sudomotor activity are controlled by a sympathetic cholinergic active vasodilator system that is hypothesized to operate through a co-transmission mechanism. To date, mechanisms of cutaneous active vasodilation remain equivocal despite many years of research by several productive laboratory groups. The purpose of this review is to highlight recent advancements in the field of cutaneous active vasodilation framed in the context of some of the historical findings that laid the groundwork for our current understanding of cutaneous active vasodilation. PMID:28349094

  17. Low power cw-laser signatures on human skin

    SciTech Connect

    Lihachev, A; Lesinsh, J; Jakovels, D; Spigulis, J

    2011-01-24

    Impact of cw laser radiation on autofluorescence features of human skin is studied. Two methods of autofluorescence detection are applied: the spectral method with the use of a fibreoptic probe and spectrometer for determining the autofluorescence recovery kinetics at a fixed skin area of {approx}12 mm{sup 2}, and the multispectral visualisation method with the use of a multispectral imaging camera for visualising long-term autofluorescence changes in a skin area of {approx}4 cm{sup 2}. The autofluorescence recovery kinetics after preliminary laser irradiation is determined. Skin autofluorescence images with visible long-term changes - 'signatures' of low power laser treatment are acquired. (application of lasers and laser-optical methods in life sciences)

  18. Using skin to assess iron accumulation in human metabolic disorders

    NASA Astrophysics Data System (ADS)

    Guinote, I.; Fleming, R.; Silva, R.; Filipe, P.; Silva, J. N.; Veríssimo, A.; Napoleão, P.; Alves, L. C.; Pinheiro, T.

    2006-08-01

    The distribution of Fe in skin was assessed to monitor body Fe status in human hereditary hemochromatosis. The paper reports on data from nine patients with hemochromatosis that were studied along the therapeutic programme. Systemic evaluation of Fe metabolism was carried out by measuring with PIXE technique the Fe concentration in plasma and blood cells, and by determining with biochemical methods the indicators of Fe transport in serum (ferritin and transferrin). The Fe distribution and concentration in skin was assessed by nuclear microscopy and Fe deposits in liver estimated through nuclear magnetic resonance. Elevated Fe concentrations in skin were related to increased plasma Fe (p < 0.004), serum ferritin content (p < 0.01) and Fe deposits in liver (p < 0.004). The relationship of Fe deposits in organs and metabolism markers may help to better understand Fe pools mobilisation and to establish the quality of skin as a marker for the disease progression and therapy efficacy.

  19. Dipeptides Increase Functional Activity of Human Skin Fibroblasts.

    PubMed

    Malinin, V V; Durnova, A O; Polyakova, V O; Kvetnoi, I M

    2015-05-01

    We analyzed the effect of dipeptide Glu-Trp and isovaleroyl-Glu-Trp in concentrations of 0.2, 2 and 20 μg/ml and Actovegin preparation on functional activity of human skin fibroblasts. Dipeptides, especially Glu-Trp, produce a stimulating effect on human skin fibroblasts and their effect is equivalent to that of Actovegin. Dipeptides stimulate cell renewal processes by activating synthesis of Ki-67 and reducing expression of caspase-9 and enhance antioxidant function of the cells by stimulating the expression of Hsp-90 and inducible NO-synthase. These findings suggest that dipeptides are promising candidates for preparations stimulating reparative processes.

  20. Skin Delivery of Kojic Acid-Loaded Nanotechnology-Based Drug Delivery Systems for the Treatment of Skin Aging

    PubMed Central

    Gonçalez, M. L.; Corrêa, M. A.; Chorilli, M.

    2013-01-01

    The aging process causes a number of changes in the skin, including oxidative stress and dyschromia. The kojic acid (KA) is iron chelator employed in treatment of skin aging, and inhibits tyrosinase, promotes depigmentation. Nanotechnology-based drug delivery systems, such as liquid crystalline systems (LCSs), can modulate drug permeation through the skin and improve the drug activity. This study is aimed at structurally developing and characterizing a kojic acid-loaded LCS, consists of water (W), cetostearyl isononanoate (oil—O) and PPG-5-CETETH-20 (surfactant-S) and evaluating its in vitro skin permeation and retention. Three regions of the diagram were selected for characterization: A (35% O, 50% S, 15% W), B (30% O, 50% S, 20% W) and C (20% O, 50% S, 30% W), to which 2% KA was added. The formulations were subjected to polarized light microscopy, which indicated the presence of a hexagonal mesophase. Texture and bioadhesion assay showed that formulation B is suitable for topical application. According to the results from the in vitro permeation and retention of KA, the formulations developed can modulate the permeation of KA in the skin. The in vitro cytotoxic assays showed that KA-unloaded LCS and KA-loaded LCS didn't present cytotoxicity. PPG-5-CETETH-20-based systems may be a promising platform for KA skin delivery. PMID:24369010

  1. Influence of human skin injury on regeneration of sensory neurons.

    PubMed

    Taherzadeh, O; Otto, W R; Anand, U; Nanchahal, J; Anand, P

    2003-06-01

    The regeneration of sensory nerve fibres is regulated by trophic factors released from their target tissue, particularly the basal epidermis, and matrix molecules. Means to modulate this response may be useful for the treatment of neuromas and painful hypertrophic scars and of sensory deficits in skin grafts and flaps. We have developed an in vitro model of sensory neuron regeneration on human skin in order to study the mechanisms of sensory dysfunction in pathological conditions. Adult rat sensory neurons were co-cultured with unfixed cryosections of normal or injured (crushed) human skin for 72 h. Neurons were immunostained for growth-associated protein-43 and the neurite lengths of neuronal cell bodies situated in various skin regions were measured. Two-way analysis of variance was performed. Neurites of sensory cell bodies on epidermis of normal skin were the shortest, with a mean +/- SEM of 75+/-10 micrometer, whereas those of cells on the dermo-epidermal junction were the longest, with a mean +/- SEM of 231+/-18 micrometer. Neurons on the dermo-epidermal junction of injured skin had significantly longer neurites than those on the same region of normal skin (mean +/- SEM = 289+/-21 micrometer). Regeneration of sensory neurons may be influenced by extracellular matrix molecules, matrix-binding growth factors and trophic factors. Altered substrate or trophic factors in injured skin may explain the increase of neurite lengths. This in vitro model may be useful for studying the molecular mechanisms of sensory recovery and the development of neuropathic pain following peripheral nerve injury.

  2. Human platelet gel supernatant inactivates opportunistic wound pathogens on skin.

    PubMed

    Edelblute, Chelsea M; Donate, Amy L; Hargrave, Barbara Y; Heller, Loree C

    2015-01-01

    Activation of human platelets produces a gel-like substance referred to as platelet rich plasma or platelet gel. Platelet gel is used clinically to promote wound healing; it also exhibits antimicrobial properties that may aid in the healing of infected wounds. The purpose of this study was to quantify the efficacy of human platelet gel against the opportunistic bacterial wound pathogens Acinetobacter baumannii, Pseudomonas aeruginosa, and Staphylococcus aureus on skin. These opportunistic pathogens may exhibit extensive antibiotic resistance, necessitating the development of alternative treatment options. The antimicrobial efficacy of platelet gel supernatants was quantified using an in vitro broth dilution assay, an ex vivo inoculated skin assay, and in an in vivo skin decontamination assay. Human platelet gel supernatants were highly bactericidal against A. baumannii and moderately but significantly bactericidal against S. aureus in vitro and in the ex vivo skin model. P. aeruginosa was not inactivated in vitro; a low but significant inactivation level was observed ex vivo. These supernatants were quite effective at inactivating a model organism on skin in vivo. These results suggest application of platelet gel has potential clinical applicability, not only in the acceleration of wound healing, but also against relevant bacteria causing wound infections.

  3. 650 GHz bistatic scattering measurements on human skin

    NASA Astrophysics Data System (ADS)

    Chamberlin, Richard A.; Mujica-Schwahn, Natalie; Grossman, Erich N.

    2014-06-01

    Many groups are developing submillimeter cameras that will be used to screen human subjects for improvised explosive devices (IEDs) and other threat items hidden beneath their clothing. To interpret submillimeter camera images the scattering properties, specifically the bidirectional scattering distribution function (BSDF) must be known. This problem is not trivial because surfaces of man-made objects and human skin have topographic features comparable to the wavelength of submillimeter radiation—thus simple, theoretical scattering approximations do not apply. To address this problem we built a goniometer instrument to measure the BSDF from skin surfaces of live human subjects illuminated with a beam from a 650 GHz synthesized source. To obtain some multi-spectral information, the instrument was reconfigured with a 160 GHz source. Skin areas sampled are from the hand, interior of the forearm, abdomen, and back. The 650 GHz beam has an approximately Gaussian profile with a FWHM of approximately 1 cm. Instrument characteristics: angular resolution 2.9⍛; noise floor -45 dB/sr; dynamic range ˃ 70 dB; either s or p-polarization; 25⍛ bidirectional-scattering-angle ≤ 180⍛ ; The human scattering target skin area was placed exactly on the goniometer center of rotation with normal angle of incidence to the source beam. Scattering power increased at the higher frequency. This new work enables radiometrically correct models of humans.

  4. Topographic diversity of fungal and bacterial communities in human skin.

    PubMed

    Findley, Keisha; Oh, Julia; Yang, Joy; Conlan, Sean; Deming, Clayton; Meyer, Jennifer A; Schoenfeld, Deborah; Nomicos, Effie; Park, Morgan; Kong, Heidi H; Segre, Julia A

    2013-06-20

    Traditional culture-based methods have incompletely defined the microbial landscape of common recalcitrant human fungal skin diseases, including athlete's foot and toenail infections. Skin protects humans from invasion by pathogenic microorganisms and provides a home for diverse commensal microbiota. Bacterial genomic sequence data have generated novel hypotheses about species and community structures underlying human disorders. However, microbial diversity is not limited to bacteria; microorganisms such as fungi also have major roles in microbial community stability, human health and disease. Genomic methodologies to identify fungal species and communities have been limited compared with those that are available for bacteria. Fungal evolution can be reconstructed with phylogenetic markers, including ribosomal RNA gene regions and other highly conserved genes. Here we sequenced and analysed fungal communities of 14 skin sites in 10 healthy adults. Eleven core-body and arm sites were dominated by fungi of the genus Malassezia, with only species-level classifications revealing fungal-community composition differences between sites. By contrast, three foot sites--plantar heel, toenail and toe web--showed high fungal diversity. Concurrent analysis of bacterial and fungal communities demonstrated that physiologic attributes and topography of skin differentially shape these two microbial communities. These results provide a framework for future investigation of the contribution of interactions between pathogenic and commensal fungal and bacterial communities to the maintainenace of human health and to disease pathogenesis.

  5. arNOX: generator of reactive oxygen species in the skin and sera of aging individuals subject to external modulation.

    PubMed

    Morré, Dorothy M; Meadows, Christiaan; Morré, D James

    2010-01-01

    An aging-related cell-surface oxidase (aging-related NADH oxidase, arNOX) generating superoxide and other reactive oxygen species is shed from the cell surface and is found in saliva, urine, perspiration, and interstitial fluids that surround the collagen and elastin matrix underlying dermis. arNOX activity correlates with age and reaches a maximum at about age 65 in males and 55 in females. arNOX activities are highly correlated with values of human skin where a causal relationship is indicated. Ongoing efforts focus on cloning arNOX proteins and development of antiaging formulas based on arNOX inhibition (intervention).

  6. Human skin microbiota: high diversity of DNA viruses identified on the human skin by high throughput sequencing.

    PubMed

    Foulongne, Vincent; Sauvage, Virginie; Hebert, Charles; Dereure, Olivier; Cheval, Justine; Gouilh, Meriadeg Ar; Pariente, Kevin; Segondy, Michel; Burguière, Ana; Manuguerra, Jean-Claude; Caro, Valérie; Eloit, Marc

    2012-01-01

    The human skin is a complex ecosystem that hosts a heterogeneous flora. Until recently, the diversity of the cutaneous microbiota was mainly investigated for bacteria through culture based assays subsequently confirmed by molecular techniques. There are now many evidences that viruses represent a significant part of the cutaneous flora as demonstrated by the asymptomatic carriage of beta and gamma-human papillomaviruses on the healthy skin. Furthermore, it has been recently suggested that some representatives of the Polyomavirus genus might share a similar feature. In the present study, the cutaneous virome of the surface of the normal-appearing skin from five healthy individuals and one patient with Merkel cell carcinoma was investigated through a high throughput metagenomic sequencing approach in an attempt to provide a thorough description of the cutaneous flora, with a particular focus on its viral component. The results emphasize the high diversity of the viral cutaneous flora with multiple polyomaviruses, papillomaviruses and circoviruses being detected on normal-appearing skin. Moreover, this approach resulted in the identification of new Papillomavirus and Circovirus genomes and confirmed a very low level of genetic diversity within human polyomavirus species. Although viruses are generally considered as pathogen agents, our findings support the existence of a complex viral flora present at the surface of healthy-appearing human skin in various individuals. The dynamics and anatomical variations of this skin virome and its variations according to pathological conditions remain to be further studied. The potential involvement of these viruses, alone or in combination, in skin proliferative disorders and oncogenesis is another crucial issue to be elucidated.

  7. A novel image-based BRDF measurement system and its application to human skin

    NASA Astrophysics Data System (ADS)

    Bintz, Jeffrey R.; Mendenhall, Michael J.; Marciniak, Michael A.; Butler, Samuel D.; Lloyd, James Tommy

    2016-09-01

    Human skin detection is an important first step in search and rescue (SAR) scenarios. Previous research performed human skin detection through an application specific camera system that ex- ploits the spectral properties of human skin at two visible and two near-infrared (NIR) wavelengths. The current theory assumes human skin is diffuse; however, it is observed that human skin exhibits specular and diffuse reflectance properties. This paper presents a novel image-based bidirectional reflectance distribution function (BRDF) measurement system, and applies it to the collection of human skin BRDF. The system uses a grid projecting laser and a novel signal processing chain to extract the surface normal from each grid location. Human skin BRDF measurements are shown for a variety of melanin content and hair coverage at the four spectral channels needed for human skin detection. The NIR results represent a novel contribution to the existing body of human skin BRDF measurements.

  8. The interrealtionship between locally applied heat, ageing and skin blood flow on heat transfer into and from the skin.

    PubMed

    Petrofsky, Jerrold; Alshahmmari, Faris; Yim, Jong Eun; Hamdan, Adel; Lee, Haneul; Neupane, Sushma; Shetye, Gauri; Moniz, Harold; Chen, Wei-Ti; Cho, Sungkwan; Pathak, Kunal; Malthane, Swapnil; Shenoy, Samruddha; Somanaboina, Karunakar; Alshaharani, Mastour; Nevgi, Bhakti; Dave, Bhargav; Desai, Rajavi

    2011-07-01

    In response to a thermal stress, skin blood flow (BF) increases to protect the skin from damage. When a very warm, noxious, heat source (44 °C) is applied to the skin, the BF increases disproportionately faster than the heat stress that was applied, creating a safety mechanism for protecting the skin. In the present investigation, the rate of rise of BF in response to applied heat at temperatures between 32 °C and 40 °C was examined as well as the thermal transfer to and from the skin with and without BF in younger and older subjects to see how the skin responds to a non-noxious heat source. Twenty male and female subjects (10 - 20-35 years, 10 - 40-70 years) were examined. The arms of the subjects were passively heated for 6 min with and without vascular occlusion by a thermode at temperatures of 32, 36, 38 or 40 °C. When occlusion was not used during the 6 min exposure to heat, there was an exponential rise in skin temperature and BF in both groups of subjects over the 6-min period. However, the older subjects achieved similar skin temperatures but with the expenditure of fewer calories from the thermode than was seen for the younger subjects (p<0.05). BF was significantly less in the older group than the younger group at rest and after exposure to each of the three warmest thermode temperatures (p<0.05). As was seen for noxious temperatures, after a delay, the rate of rise of BF at the three warmest thermode temperatures was faster than the rise in skin temperature in the younger group but less in the older group of subjects. Thus, a consequence of ageing is reduced excess BF in response to thermal stress increasing susceptibility to thermal damage. This must be considered in modelling of BF.

  9. Noninvasive and high-resolving photoacoustic dermoscopy of human skin

    PubMed Central

    Xu, Dong; Yang, Sihua; Wang, Ying; Gu, Ying; Xing, Da

    2016-01-01

    We proposed and developed a photoacoustic (PA) dermoscope equipped with an integrated PA probe to achieve quantification and high-resolution, high-contrast deep imaging of human skin. The PA probe, with light-sound confocal excitation and reception, is specially designed, and integrated with an objective lens, an ultrasound transducer, and an inverted-triangle coupling cup to facilitate convenient implementation in a clinical setting. The PA dermoscope was utilized for noninvasive and high-resolution imaging of epidermal and dermal structure in volunteers. The imaging results demonstrated that the characteristic parameters of skin disease, including pigment distribution and thickness, vascular diameter, and depth, can be obtained by the PA dermoscope, confirming that PA dermoscopy can serve as a potential tool for the diagnosis and curative effect evaluation of human skin disease. PMID:27375929

  10. Human skin transcriptome during superficial cutaneous wound healing.

    PubMed

    Nuutila, Kristo; Siltanen, Antti; Peura, Matti; Bizik, Jozef; Kaartinen, Ilkka; Kuokkanen, Hannu; Nieminen, Tapio; Harjula, Ari; Aarnio, Pertti; Vuola, Jyrki; Kankuri, Esko

    2012-01-01

    Healing of the epidermis is a crucial process for maintaining the skin's defense integrity and its resistance to environmental threats. Compromised wound healing renders the individual readily vulnerable to infections and loss of body homeostasis. To clarify the human response of reepithelialization, we biopsied split-thickness skin graft donor site wounds immediately before and after harvesting, as well as during the healing process 3 and 7 days thereafter. In all, 25 biopsies from eight patients qualified for the study. All samples were analyzed by genome-wide microarrays. Here, we identified the genes associated with normal skin reepithelialization over time and organized them by similarities according to their induction or suppression patterns during wound healing. Our results provide the first elaborate insight into the transcriptome during normal human epidermal wound healing. The data not only reveal novel genes associated with epidermal wound healing but also provide a fundamental basis for the translational interpretation of data acquired from experimental models.

  11. Technical note: comparing von Luschan skin color tiles and modern spectrophotometry for measuring human skin pigmentation.

    PubMed

    Swiatoniowski, Anna K; Quillen, Ellen E; Shriver, Mark D; Jablonski, Nina G

    2013-06-01

    Prior to the introduction of reflectance spectrophotometry into anthropological field research during the 1950s, human skin color was most commonly classified by visual skin color matching using the von Luschan tiles, a set of 36 standardized, opaque glass tiles arranged in a chromatic scale. Our goal was to establish a conversion formula between the tile-based color matching method and modern reflectance spectrophotometry to make historical and contemporary data comparable. Skin pigmentation measurements were taken on the forehead, inner upper arms, and backs of the hands using both the tiles and a spectrophotometer on 246 participants showing a broad range of skin pigmentation. From these data, a second-order polynomial conversion formula was derived by jackknife analysis to estimate melanin index (M-index) based on tile values. This conversion formula provides a means for comparing modern data to von Luschan tile measurements recorded in historical reports. This is particularly important for populations now extinct, extirpated, or admixed for which tile-based measures of skin pigmentation are the only data available.

  12. Telocytes in human skin – are they involved in skin regeneration?

    PubMed Central

    Ceafalan, Laura; Gherghiceanu, Mihaela; Popescu, L M; Simionescu, Olga

    2012-01-01

    Abstract Telocytes (TCs), a particular interstitial cell type, have been recently described in a wide variety of mammalian organs (www.telocytes.com). The TCs are identified morphologically by a small cell body and extremely long (tens to hundreds of μm), thin prolongations (less than 100 nm in diameter, below the resolving power of light microscopy) called telopodes. Here, we demonstrated with electron microscopy and immunofluorescence that TCs were present in human dermis. In particular, TCs were found in the reticular dermis, around blood vessels, in the perifollicular sheath, outside the glassy membrane and surrounding sebaceous glands, arrector pili muscles and both the secretory and excretory portions of eccrine sweat glands. Immunofluorescence screening and laser scanning confocal microscopy showed two subpopulations of dermal TCs; one expressed c-kit/CD117 and the other was positive for CD34. Both subpopulations were also positive for vimentin. The TCs were connected to each other by homocellular junctions, and they formed an interstitial 3D network. We also found TCs adjoined to stem cells in the bulge region of hair follicles. Moreover, TCs established atypical heterocellular junctions with stem cells (clusters of undifferentiated cells). Given the frequency of allergic skin pathologies, we would like to emphasize the finding that close, planar junctions were frequently observed between TCs and mast cells. In conclusion, based on TC distribution and intercellular connections, our results suggested that TCs might be involved in skin homeostasis, skin remodelling, skin regeneration and skin repair. PMID:22500885

  13. Opinions regarding skin ageing in the elderly inhabitants of Bialystok, Poland

    PubMed Central

    Krajewska-Kulak, Elzbieta

    2016-01-01

    Skin diseases constitute an essential health and aesthetic problem in the elderly. The aim of the study was to evaluate the knowledge of the elderly residents of public nursing homes and participants of the University of the Third Age in Bialystok, Poland surrounding the factors influencing skin ageing, the awareness of skin conditions in agening skin, and the impact of skin ageing on the volunteers. The study was performed from April to June 2015 in Bialystok, in two groups: among 100 public nursing home residents (PNH) and 100 members of University of the Third Age (U3A), (all over 60 years old). The study made use of a diagnostic survey conducted via a questionnaire prepared by the authors. Nearly half of those surveyed (42.5%; n = 85) sunbathed in the past, while 28.0% (n = 56) of those surveyed now take part in this type of leisure activity. More than half of respondents (53.0%; n = 106) protected their skin using special protective preparations. A majority of Bialystok inhabitants surveyed (80.5%; n = 161) noticed the features of skin ageing. They reported birthmarks, fungal infections and bedsores as the main skin problems of the old age. Nearly half (40%) of respondents assessed their knowledge as average and 26.0% as poor. The study showed some statistical differences in the knowledge and awareness between the residents of public nursing homes and the students of the University of the Third Age, e.g., the use of the Internet by the U3A group for finding out information. There is a desire to receive education in the field of the agening skin conditions/diseases among the elderly because their level of knowledge is relatively poor. Education of seniors in this area can increase their awareness of the basic principles of skin care and prevention marking of skin ageing. The benefits of greater knowledge of seniors about the conditions of agening skin can help reduce the medical burden and reduce the incidence on certain skin diseases. Furthermore, there is a

  14. Fibroblast-mediated contraction in actinically exposed and actinically protected aging skin

    SciTech Connect

    Marks, M.W.; Morykwas, M.J.; Wheatley, M.J. )

    1990-08-01

    The changes in skin morphology over time are a consequence of both chronologic aging and the accumulation of environmental exposure. Through observation, we know that actinic radiation intensifies the apparent aging of skin. We have investigated the effects of aging and actinic radiation on the ability of fibroblasts to contract collagen-fibroblast lattices. Preauricular and postauricular skin samples were obtained from eight patients aged 49 to 74 undergoing rhytidectomy. The samples were kept separate, and the fibroblasts were grown in culture. Lattices constructed with preauricular fibroblasts consistently contracted more than lattices containing postauricular fibroblasts. The difference in amount of contraction in 7 days between sites was greatest for the younger patients and decreased linearly as donor age increased (r = -0.96). This difference may be due to preauricular fibroblasts losing their ability to contract a lattice as aging skin is exposed to more actinic radiation.

  15. Caffeine protects human skin fibroblasts from acute reactive oxygen species-induced necrosis.

    PubMed

    Silverberg, Jonathan I; Patel, Mital; Brody, Neil; Jagdeo, Jared

    2012-11-01

    Oxidative damage by reactive oxygen species (ROS) plays a major role in aging and carcinogenesis. Little is known about either the effects of acute ROS in necrosis and inflammation of skin or the therapeutic agents for prevention and treatment. Previously, our laboratory identified caffeine as an inhibitor of hydrogen peroxide (H2O2)-generated lipid peroxidation products in human skin fibroblasts. Here, we study effects of caffeine on acute ROS-mediated necrosis. Human skin fibroblasts were incubated with caffeine, followed by H2O2 challenge. Flow cytometry was used to analyze cell morphology, counts, apoptosis and necrosis, and ROS. We found that caffeine protects from H2O2 cell damage at lower (0.01 mM) and intermediate (0.1 mM) doses. The beneficial effects of caffeine appear to be mediated by a mechanism other than antioxidant function.

  16. Solar UV radiation reduces the barrier function of human skin.

    PubMed

    Biniek, Krysta; Levi, Kemal; Dauskardt, Reinhold H

    2012-10-16

    The ubiquitous presence of solar UV radiation in human life is essential for vitamin D production but also leads to skin photoaging, damage, and malignancies. Photoaging and skin cancer have been extensively studied, but the effects of UV on the critical mechanical barrier function of the outermost layer of the epidermis, the stratum corneum (SC), are not understood. The SC is the first line of defense against environmental exposures like solar UV radiation, and its effects on UV targets within the SC and subsequent alterations in the mechanical properties and related barrier function are unclear. Alteration of the SC's mechanical properties can lead to severe macroscopic skin damage such as chapping and cracking and associated inflammation, infection, scarring, and abnormal desquamation. Here, we show that UV exposure has dramatic effects on cell cohesion and mechanical integrity that are related to its effects on the SC's intercellular components, including intercellular lipids and corneodesmosomes. We found that, although the keratin-controlled stiffness remained surprisingly constant with UV exposure, the intercellular strength, strain, and cohesion decreased markedly. We further show that solar UV radiation poses a double threat to skin by both increasing the biomechanical driving force for damage while simultaneously decreasing the skin's natural ability to resist, compromising the critical barrier function of the skin.

  17. High-definition optical coherence tomography intrinsic skin ageing assessment in women: a pilot study.

    PubMed

    Boone, M A L M; Suppa, M; Marneffe, A; Miyamoto, M; Jemec, G B E; Del Marmol, V

    2015-10-01

    Several non-invasive two-dimensional techniques with different lateral resolution and measurable depth range have proved to be useful in assessing and quantifying morphological changes in skin ageing. Among these, only in vivo microscopy techniques permit histometric measurements in vivo. Qualitative and quantitative assessment of chronological (intrinsic) age-related (IAR) morphological changes of epidermis, dermo-epidermal junction (DEJ), papillary dermis (PD), papillary-reticular dermis junction and reticular dermis (RD) have been performed by high-definition optical coherence tomography in real time 3-D. HD-OCT images were taken at the internal site of the right upper arm. Qualitative HD-OCT IAR descriptors were reported at skin surface, at epidermal layer, DEJ, PD and upper RD. Quantitative evaluation of age-related compaction and backscattered intensity or brightness of different skin layers was performed by using the plugin plot z-axis profile of ImageJ(®) software permitting intensity assessment of HD-OCT (DICOM) images (3-D images). Analysis was in blind from all clinical information. Sixty, fair-skinned (Fitzpatrick types I-III) healthy females were analysed retrospectively in this study. The subjects belonged to three age groups: twenty in group I aged 20-39, twenty in group II aged 40-59 and twenty in group III aged 60-79. Only intrinsic ageing in women has been studied. Significant age-related qualitative and quantitative differences could be noticed. IAR changes in dermal matrix fibers morphology/organisation and in microvasculature were observed. The brightness and compaction of the different skin layers increased significantly with intrinsic skin ageing. The depth of visibility of fibers in RD increased significantly in the older age group. In conclusion, HD-OCT allows 3-D in vivo and real time qualitative and quantitative assessment of chronological (intrinsic) age-related morphological skin changes at high resolution from skin surface to a depth

  18. Generalization of Extinguished Skin Conductance Responding in Human Fear Conditioning

    ERIC Educational Resources Information Center

    Vervliet, Bram; Vansteenwegen, Debora; Eelen, Paul

    2004-01-01

    In a human fear conditioning paradigm using the skin conductance response (SCR), participants were assigned to two groups. Following identical acquisition, group ABA (n = 16) was extinguished to a generalization stimulus (GS), whereas group AAB (n = 20) was extinguished to the conditioned stimulus (CS). At test, presenting the CS in group ABA…

  19. Sarcoptes scabiei mites modulate gene expression in human skin equivalents.

    PubMed

    Morgan, Marjorie S; Arlian, Larry G; Markey, Michael P

    2013-01-01

    The ectoparasitic mite, Sarcoptes scabiei that burrows in the epidermis of mammalian skin has a long co-evolution with its hosts. Phenotypic studies show that the mites have the ability to modulate cytokine secretion and expression of cell adhesion molecules in cells of the skin and other cells of the innate and adaptive immune systems that may assist the mites to survive in the skin. The purpose of this study was to identify genes in keratinocytes and fibroblasts in human skin equivalents (HSEs) that changed expression in response to the burrowing of live scabies mites. Overall, of the more than 25,800 genes measured, 189 genes were up-regulated >2-fold in response to scabies mite burrowing while 152 genes were down-regulated to the same degree. HSEs differentially expressed large numbers of genes that were related to host protective responses including those involved in immune response, defense response, cytokine activity, taxis, response to other organisms, and cell adhesion. Genes for the expression of interleukin-1α (IL-1α) precursor, IL-1β, granulocyte/macrophage-colony stimulating factor (GM-CSF) precursor, and G-CSF precursor were up-regulated 2.8- to 7.4-fold, paralleling cytokine secretion profiles. A large number of genes involved in epithelium development and keratinization were also differentially expressed in response to live scabies mites. Thus, these skin cells are directly responding as expected in an inflammatory response to products of the mites and the disruption of the skin's protective barrier caused by burrowing. This suggests that in vivo the interplay among these skin cells and other cell types, including Langerhans cells, dendritic cells, lymphocytes and endothelial cells, is responsible for depressing the host's protective response allowing these mites to survive in the skin.

  20. Raman measurement of carotenoid composition in human skin

    NASA Astrophysics Data System (ADS)

    Ermakov, Igor V.; Ermakova, Maia R.; Gellermann, Werner

    2004-07-01

    The carotenoids lycopene and beta-carotene are powerful antioxidants in skin and are thought to act as scavengers for free radicals and singlet oxygen. The role of carotenoid species in skin health is of strong current interest. We demonstrate the possibility to use Resonance Raman spectroscopy for fast, non-invasive, highly specific, and quantitative detection of beta-carotene and lycopene in human skin. Analyzing Raman signals originating from the carbon-carbon double bond stretch vibrations of the carotenoid molecules under blue and green laser excitation, we were able to characterize quantitatively the relative concentrations of each carotenoid species in-vivo. In the selective detection, we take advantage of different Raman cross-section spectral profiles for beta-carotene and lycopene molecules, and obtain a quantitative assessment of individual long-chain carotenoid species in the skin rather than their cumulative levels. Preliminary dual-wavelength Raman measurements reveal significant differences in the carotenoid composition of different subjects. The technique holds promise for rapid screening of carotenoid compositions in human skin in large populations and may be suitable in clinical studies for assessing the risk for cutaneous diseases.

  1. Damage from periorbital ageing to the multilayered structures and resilience of the skin in Chinese population

    PubMed Central

    Liao, Chuh-Kai; Tsai, Feng-Chou; Fong, Tsorng-Harn; Hu, Chien-Ming; Wei, Po-Li; Su, Ching-Hua

    2013-01-01

    Ageing dynamically disrupts the multilayered supporting components of the skin that are held together by cell adhesion molecules (CAMs). Skin specimens from 33 female Chinese patients undergoing lower blepharoplasty were divided into three age groups and examined by haematoxylin and eosin (H&E) staining, immunohistochemistry (IHC) and Elastica-van Gieson (EVG) stains, western blotting, surface electron microscopy (SEM) and biomechanical tension analysis. The SEM density (skin surface topology) showed a negative linear relationship with age. The triangular pattern of the skin surface in the younger group gradually broke down into quadrangular and irregular patterns in the older group. Collagens and elastic fibres in the dermis showed anisotropy and decreased density in the older groups compared with the younger group, especially in the papillary dermis. Anisotropy means that physical properties differ according to the direction of measurement. E-cadherin and integrin αv (whose functions are to bind epidermal and dermal elements respectively) increased and decreased, respectively, in the oldest group. Skin resilience decreased significantly in this group under repetitive stress. In conclusion, a loss of skin surface textures, integrin αv expressions, epidermal-dermal connections and dermal compactness led to the multilayered structure of the skin becoming separated. This in turn decreased resilience during ageing. These findings may therefore explain why aged skins cannot tolerate repetitive facial expressions, and why this action produces further dynamic wrinkles. PMID:23441675

  2. Anti-Aging Effects of the Hanwoo Leg Bone, Foot and Tail Infusions (HLI, HFI and HTI) on Skin Fibroblast

    PubMed Central

    Yoon, Ji Young; Jeong, Hee Sun; Joo, Nami

    2016-01-01

    Many researchers revealed that collagen contribute to maintaining the skin’s elasticity and inhibit wrinkling of skin. Korean native cattle (Hanwoo) bone (leg bone, foot and tail) infusion contains the various inorganic materials, collagen and chondroitin sulfate. All of this, a large quantity of collagen is included in Hanwoo infusion. Therefore, this study emphasized on the effects of collagen in the Hanwoo bone infusion. For the first time, Hanwoo bone infusions were directly added to the media of Human Dermal Fibroblast (NHDF-c) to test anti-aging effects. First, it was identified that growth rate of skin fibroblast was increased. Furthermore, the Hanwoo bone infusion increased a 50% of fibroblast collagen synthesis. Also, suppression of skin fibroblast aging was confirmed by treatment Hanwoo bone infusion. In conclusion, this study demonstrates the effects of infusion made from Hanwoo leg bone, foot and tail on anti-aging, wrinkle inhibiting and skin fibroblast elasticity maintaining. Therefore, this study identified that traditional infusion has effects that are good for skin elasticity. PMID:27194933

  3. Pumpless microfluidic platform for drug testing on human skin equivalents

    PubMed Central

    Abaci, Hasan Erbil; Gledhill, Karl; Guo, Zongyou; Christiano, Angela M.; Shuler, Michael L.

    2014-01-01

    Advances in bio-mimetic in vitro human skin models increase the efficiency of drug screening studies. In this study, we designed and developed a microfluidic platform that allows for long-term maintenance of full thickness human skin equivalents (HSE) which are comprised of both the epidermal and dermal compartments. The design is based on the physiologically relevant blood residence times in human skin tissue and allows for the establishment of an air-epidermal interface which is crucial for maturation and terminal differentiation of HSEs. The small scale of the design reduces the amount of culture medium and the number of cells required by 36 fold compared to conventional transwell cultures. Our HSE-on-a-chip platform has the capability to recirculate the medium at desired flow rates without the need for pump or external tube connections. We demonstrate that the platform can be used to maintain HSEs for three weeks with proliferating keratinocytes similar to conventional HSE cultures. Immunohistochemistry analyses show that the differentiation and localization of keratinocytes was successfully achieved, establishing all sub-layers of the epidermis after one week. Basal keratinocytes located at the epidermal-dermal interface remain in a proliferative state for three weeks. We use a transdermal transport model to show that the skin barrier function is maintained for three weeks. We also validate the capability of the HSE-on-a-chip platform to be used for drug testing purposes by examining the toxic effects of doxorubucin on skin cells and structure. Overall, the HSE-on-a-chip is a user-friendly and cost-effective in vitro platform for drug testing of candidate molecules for skin disorders. PMID:25490891

  4. Pumpless microfluidic platform for drug testing on human skin equivalents.

    PubMed

    Abaci, Hasan Erbil; Gledhill, Karl; Guo, Zongyou; Christiano, Angela M; Shuler, Michael L

    2015-02-07

    Advances in bio-mimetic in vitro human skin models increase the efficiency of drug screening studies. In this study, we designed and developed a microfluidic platform that allows for long-term maintenance of full thickness human skin equivalents (HSE) which are comprised of both the epidermal and dermal compartments. The design is based on the physiologically relevant blood residence times in human skin tissue and allows for the establishment of an air-epidermal interface which is crucial for maturation and terminal differentiation of HSEs. The small scale of the design reduces the amount of culture medium and the number of cells required by 36 fold compared to conventional transwell cultures. Our HSE-on-a-chip platform has the capability to recirculate the medium at desired flow rates without the need for pump or external tube connections. We demonstrate that the platform can be used to maintain HSEs for three weeks with proliferating keratinocytes similar to conventional HSE cultures. Immunohistochemistry analyses show that the differentiation and localization of keratinocytes was successfully achieved, establishing all sub-layers of the epidermis after one week. Basal keratinocytes located at the epidermal-dermal interface remain in a proliferative state for three weeks. We use a transdermal transport model to show that the skin barrier function is maintained for three weeks. We also validate the capability of the HSE-on-a-chip platform to be used for drug testing purposes by examining the toxic effects of doxorubucin on skin cells and structure. Overall, the HSE-on-a-chip is a user-friendly and cost-effective in vitro platform for drug testing of candidate molecules for skin disorders.

  5. Epidermis of Human Skin: Pyroelectric and Piezoelectric Sensor Layer

    NASA Astrophysics Data System (ADS)

    Athenstaedt, Herbert; Claussen, Helge; Schaper, Daniel

    1982-05-01

    The epidermis of live human skin has a permanent electric dipole moment perpendicular to its surface. Voltage responses to a rapid change of temperature are pyroelectric, while voltage responses to pressure pulses are piezoelectric in nature. The time course of the responses depends on dX/dt (X, temperature or pressure). The epidermal surface can react to all physical environmental influences to which nonbiological pyroelectric materials are known to respond. Epidermal voltage signals can be perceived through the intraepidermal and the superficial dermal nervous network. The pyroelectric and piezoelectric properties are also measurable on dead, dry skin samples.

  6. Optoelectronic set for measuring reflectance spectrum of living human skin

    NASA Astrophysics Data System (ADS)

    Gryko, Lukasz; Zajac, Andrzej; Gilewski, Marian; Kulesza, Ewa

    2015-09-01

    In the paper the authors present the developed optoelectronic set for measuring spectral reflectance of living human skin. The basic elements of the set are: the illuminator consists of the LED illuminator emitting a uniform distribution of spectral irradiance in the exposed field, the semispherical measuring chamber and the spectrometer which measures spectrum of reflected radiation. Measured radiation is from spectral range of tissue optical window (from 600 nm to 1000 nm). Knowledge about the reflectance spectrum of the patient skin allows adjusting spectral and energetic parameters of the radiation used in biostimulation treatment. The developed set also enables the repeatable exposures of patients in the Low Level Laser Therapy procedures.

  7. Effects of intrinsic aging and photodamage on skin dyspigmentation: an explorative study

    NASA Astrophysics Data System (ADS)

    Dobos, Gabor; Trojahn, Carina; D'Alessandro, Brian; Patwardhan, Sachin; Canfield, Douglas; Blume-Peytavi, Ulrike; Kottner, Jan

    2016-06-01

    Photoaging is associated with increasing pigmentary heterogeneity and darkening of skin color. However, little is known about age-related changes in skin pigmentation on sun-protected areas. The aim of this explorative study was to measure skin color and dyspigmentation using image processing and to evaluate the reliability of these parameters. Twenty-four volunteers of three age-groups were included in this explorative study. Measurements were conducted at sun-exposed and sun-protected areas. Overall skin-color estimates were similar among age groups. The hyper- and hypopigmentation indices differed significantly by age groups and their correlations with age ranged between 0.61 and 0.74. Dorsal forearm skin differed from the other investigational areas (p<0.001). We observed an increase in dyspigmentation at all skin areas, including sun-protected skin areas, already in young adulthood. Associations between age and dyspigmentation estimates were higher compared to color parameters. All color and dyspigmentation estimates showed high reliability. Dyspigmentation parameters seem to be better biomarkers for UV damage than the overall color measurements.

  8. Evaluation of a Silicone Membrane as an Alternative to Human Skin for Determining Skin Permeation Parameters of Chemical Compounds.

    PubMed

    Uchida, Takashi; Yakumaru, Masafumi; Nishioka, Keisuke; Higashi, Yoshihiro; Sano, Tomohiko; Todo, Hiroaki; Sugibayashi, Kenji

    2016-01-01

    We evaluated the effectiveness of a silicone membrane as an alternative to human skin using the skin permeation parameters of chemical compounds. An in vitro permeation study using 15 model compounds was conducted, and permeation parameters comprising permeability coefficient (P), diffusion parameter (DL(-2)), and partition parameter (KL) were calculated from each permeation profile. Significant correlations were obtained in log P, log DL(-2), and log KL values between the silicone membrane and human skin. DL(-2) values of model compounds, except flurbiprofen, in the silicone membrane were independent of the lipophilicity of the model compounds and were 100-fold higher than those in human skin. For antipyrine and caffeine, which are hydrophilic, KL values in the silicone membrane were 100-fold lower than those in human skin, and P values, calculated as the product of a DL(-2) and KL, were similar. For lipophilic compounds, such as n-butyl paraben and flurbiprofen, KL values for silicone were similar to or 10-fold higher than those in human skin, and P values for silicone were 100-fold higher than those in human skin. Furthermore, for amphiphilic compounds with log Ko/w values from 0.5 to 3.5, KL values in the silicone membrane were 10-fold lower than those in human skin, and P values for silicone were 10-fold higher than those in human skin. The silicone membrane was useful as a human skin alternative in an in vitro skin permeation study. However, depending on the lipophilicity of the model compounds, some parameters may be over- or underestimated.

  9. [Molecular Mechanisms of Functional Activity Decreasing of the Skin Cells With Its Aging].

    PubMed

    Khavinson, V Kh; Linkova, N S; Kukanova, E O; Orlova, O A

    2016-01-01

    The article discusses the pool of signaling molecules that regulate the functional activity of the skin cells. Molecules of apoptosis and cells skin aging are p53, p21, p15, Cdk 4/6 and Bcl-2. Inflammation in skin fibroblasts are realized through the cytokines TNF-α, TGF-β, IL-1, ICAM-1, matrix metalloproteinase MMP-1,2,3,9, transcription factor NF-κB and activator protein AP-1. An important role in the aging of skin cells play neuroimmunoendocrine signaling molecules--melatonin, serotonin, skin fibroblast proliferation marker chromogranin A and CD98hc. Age-related changes in the activity of immune cells of the skin is associated with impaired expression of cluster of differentiation of T-lymphocytes (CD3, CD4, CD5, CD8, CD11) and dendritic cells (CD83⁺). These signaling molecules produced by the fibroblasts of the skin, regulate the activity of immune cells involved in the cascade of reactions associated with inflammatory responses, proliferation, apoptosis and cell regeneration. Based on these data nowadays new highly selective approaches to the diagnosis of the skin and the creation of cosmetic agents for the prevention of aging are developed.

  10. Thermal effusivity of human skin by photoacoustic technique

    NASA Astrophysics Data System (ADS)

    Varela-Najera, Jose B.; Cordova-Fraga, Teodor; Vargas-Luna, Miguel; Gutierrez-Juarez, Gerardo

    2000-05-01

    In this work, we show a particular setup, which is based on the conventional photoacoustic cell, to measure thermal effusivity of human skin in-vivo and in-situ. We measure the changes of thermal effusivity due to the absorption of sunscreen into the skin and these values are compared with those from an adjacent sample of clean skin. This experiment was performed on a volunteer's forearm and stainless steel as the thermally thin absorption surface. The values for this parameter are in good agreement with those reported in the literature. Besides the measurements described above, with the same setup we got the thermal effusivity of the sunscreen itself as a reference parameter. R

  11. Coniosporium epidermidis sp. nov., a new species from human skin

    PubMed Central

    Li, D. M.; de Hoog, G.S.; Saunte, D.M. Lindhardt; van den Ende, A.H.G. Gerrits; Chen, X. R.

    2008-01-01

    Coniosporium epidermidis sp. nov. is described from a superficial skin lesion with blackish discolouration in an 80-yr-old Chinese patient. The species produces dark, thick-walled, inflated, reluctantly liberating arthroconidia without longitudinal septa. Sequences of the ribosomal operon, as well as of the translation elongation factor 1-α support its novelty. The species is found in a lineage basal to the order Chaetothyriales, amidst relatives from rock, but also species repeatedly isolated from human skin and nails and eventually causing mild cutaneous infections. Coniosporium epidermidis is consistently found on humans, either asymptomatic or symptomatic. The species indicates a change of life style towards human pathogenicity, which is a recurrent type of ecology in derived Chaetothyriales. Superficial and cutaneous infection by melanized fungi is a new category in dermatology. PMID:19287535

  12. Near infrared laser penetration and absorption in human skin

    NASA Astrophysics Data System (ADS)

    Nasouri, Babak; Murphy, Thomas E.; Berberoglu, Halil

    2014-02-01

    For understanding the mechanisms of low level laser/light therapy (LLLT), accurate knowledge of light interaction with tissue is necessary. In this paper, we present a three dimensional, multi-layer Monte Carlo simulation tool for studying light penetration and absorption in human skin. The skin is modeled as a three-layer participating medium, namely epidermis, dermis, and subcutaneous, where its geometrical and optical properties are obtained from the literature. Both refraction and reflection are taken into account at the boundaries according to Snell's law and Fresnel relations. A forward Monte Carlo method was implemented and validated for accurately simulating light penetration and absorption in absorbing and anisotropically scattering media. Local profiles of light penetration and volumetric absorption densities were simulated for uniform as well as Gaussian profile beams with different spreads at 155 mW average power over the spectral range from 1000 nm to 1900 nm. The results show the effects of beam profiles and wavelength on the local fluence within each skin layer. Particularly, the results identify different wavelength bands for targeted deposition of power in different skin layers. Finally, we show that light penetration scales well with the transport optical thickness of skin. We expect that this tool along with the results presented will aid researchers resolve issues related to dose and targeted delivery of energy in tissues for LLLT.

  13. Background free imaging of upconversion nanoparticle distribution in human skin

    NASA Astrophysics Data System (ADS)

    Song, Zhen; Anissimov, Yuri G.; Zhao, Jiangbo; Nechaev, Andrei V.; Nadort, Annemarie; Jin, Dayong; Prow, Tarl W.; Roberts, Michael S.; Zvyagin, Andrei V.

    2013-06-01

    Widespread applications of nanotechnology materials have raised safety concerns due to their possible penetration through skin and concomitant uptake in the organism. This calls for systematic study of nanoparticle transport kinetics in skin, where high-resolution optical imaging approaches are often preferred. We report on application of emerging luminescence nanomaterial, called upconversion nanoparticles (UCNPs), to optical imaging in skin that results in complete suppression of background due to the excitation light back-scattering and biological tissue autofluorescence. Freshly excised intact and microneedle-treated human skin samples were topically coated with oil formulation of UCNPs and optically imaged. In the first case, 8- and 32-nm UCNPs stayed at the topmost layer of the intact skin, stratum corneum. In the second case, 8-nm nanoparticles were found localized at indentations made by the microneedle spreading in dermis very slowly (estimated diffusion coefficient, Dnp=3-7×10-12 cm2.s-1). The maximum possible UCNP-imaging contrast was attained by suppressing the background level to that of the electronic noise, which was estimated to be superior in comparison with the existing optical labels.

  14. Fluorescence spectroscopy for endogenous porphyrins in human facial skin

    NASA Astrophysics Data System (ADS)

    Seo, I.; Tseng, S. H.; Cula, G. O.; Bargo, P. R.; Kollias, N.

    2009-02-01

    The activity of certain bacteria in skin is known to correlate to the presence of porphyrins. In particular the presence of coproporphyrin produced by P.acnes inside plugged pores has been correlated to acne vulgaris. Another porphyrin encountered in skin is protoporphyrin IX, which is produced by the body in the pathway for production of heme. In the present work, a fluorescence spectroscopy system was developed to measure the characteristic spectrum and quantify the two types of porphyrins commonly present in human facial skin. The system is comprised of a Xe lamp both for fluorescence excitation and broadband light source for diffuse reflectance measurements. A computer-controlled filter wheel enables acquisition of sequential spectra, first excited by blue light at 405 nm then followed by the broadband light source, at the same location. The diffuse reflectance spectrum was used to correct the fluorescence spectrum due to the presence of skin chromophores, such as blood and melanin. The resulting fluorescence spectra were employed for the quantification of porphyrin concentration in a population of healthy subjects. The results show great variability on the concentration of these porphyrins and further studies are being conducted to correlate them with skin conditions such as inflammation and acne vulgaris.

  15. Noncontacting diffuse VIS-NIR spectroscopy of human skin for evaluation of skin type and time-dependent microcirculation

    NASA Astrophysics Data System (ADS)

    Schmidt, Wolf-Dieter; Fassler, Dieter; Zimmermann, Gabi; Liebold, Kristin; Wollina, Uwe

    2000-11-01

    Spectroscopic investigations of the VIS-NIR range allow the objective determination of pigmentation, blood microcirculation and water content of human skin. Non- contacting in vivo measurements of the human skin of 50 volunteers reflect the clinical skin type well. Our correlation analysis yields that the red/infrared spectral range can be used for a determination of skin type. The observed strong spectral variations within the same group of skin type are likely based on the high biological variability of human skin and subjective clinically observed skin type. Therefore it can be useful to measure the full spectral range and to calculate a non-observed skin score with multivariate spectral methods. By multivariate analysis a correct classification of remittance spectra can be obtained. Time- depending spectral variations of dermal microcirculation can be measured at defined locations of the body, for instance the dynamics of oxygenation or blood volume in the skin of the fingertip. The cardial, pulmonal and vasomotoric waves of the micro- and macrocirculation are clearly visible at different wavelengths. The spectroscopic informations are important as an objective measure for the skin type evaluation, the penetration behavior of pharmaca, laser surgery, and therapy.

  16. Three-Dimensional In Vitro Skin and Skin Cancer Models Based on Human Fibroblast-Derived Matrix.

    PubMed

    Berning, Manuel; Prätzel-Wunder, Silke; Bickenbach, Jackie R; Boukamp, Petra

    2015-09-01

    Three-dimensional in vitro skin and skin cancer models help to dissect epidermal-dermal and tumor-stroma interactions. In the model presented here, normal human dermal fibroblasts isolated from adult skin self-assembled into dermal equivalents with their specific fibroblast-derived matrix (fdmDE) over 4 weeks. The fdmDE represented a complex human extracellular matrix that was stabilized by its own heterogeneous collagen fiber meshwork, largely resembling a human dermal in vivo architecture. Complemented with normal human epidermal keratinocytes, the skin equivalent (fdmSE) thereof favored the establishment of a well-stratified and differentiated epidermis and importantly allowed epidermal regeneration in vitro for at least 24 weeks. Moreover, the fdmDE could be used to study the features of cutaneous skin cancer. Complementing fdmDE with HaCaT cells in different stages of malignancy or tumor-derived cutaneous squamous cell carcinoma cell lines, the resulting skin cancer equivalents (fdmSCEs) recapitulated the respective degree of tumorigenicity. In addition, the fdmSCE invasion phenotypes correlated with their individual degree of tissue organization, disturbance in basement membrane organization, and presence of matrix metalloproteinases. Together, fdmDE-based models are well suited for long-term regeneration of normal human epidermis and, as they recapitulate tumor-specific growth, differentiation, and invasion profiles of cutaneous skin cancer cells, also provide an excellent human in vitro skin cancer model.

  17. Bilayer hydrogel with autologous stem cells derived from debrided human burn skin for improved skin regeneration.

    PubMed

    Natesan, Shanmugasundaram; Zamora, David O; Wrice, Nicole L; Baer, David G; Christy, Robert J

    2013-01-01

    The objective of this study was to demonstrate that stem cells isolated from discarded skin obtained after debridement can be used with collagen and fibrin-based scaffolds to develop a tissue-engineered vascularized dermal equivalent. Discarded tissue samples were collected from severely burned patients undergoing wound debridement. Stem cells were isolated from the adipose tissue layer and their growth and immunophenotype characterized. To develop a skin equivalent, debrided skin adipose stem cells (dsASCs) were added to a collagen-polyethylene glycol (PEG) fibrin-based bilayer hydrogel and analyzed in vitro. The effect of the bilayered hydrogels on wound healing was demonstrated using an excision wound model in athymic rats. The dsASCs isolated from all samples were CD90, CD105, and stromal cell surface protein-1 positive, similar to adipose stem cells isolated from normal human lipoaspirates. Within the bilayer hydrogels, dsASCs proliferated and differentiated, maintained a spindle-shaped morphology in collagen, and developed a tubular microvascular network in the PEGylated fibrin. Rat excision wounds treated with bilayer hydrogels showed less wound contraction and exhibited better dermal matrix deposition and epithelial margin progression than controls. Stem cells can be isolated from the adipose layer of burned skin obtained during debridement. When dsASCs are incorporated within collagen-PEGylated fibrin bilayer hydrogels, they develop stromal and vascular phenotypes through matrix-directed differentiation without use of growth factors. Preliminary in vivo studies indicate that dsASC-bilayer hydrogels contribute significantly to wound healing and provide support for their use as a vascularized dermal substitute for skin regeneration to treat large surface area burns.

  18. Local heating of human skin causes hyperemia without mediation by muscarinic cholinergic receptors or prostanoids.

    PubMed

    Golay, Sandrine; Haeberli, Christian; Delachaux, Anne; Liaudet, Lucas; Kucera, Paul; Waeber, Bernard; Feihl, François

    2004-11-01

    Local changes in surface temperature have a powerful influence on the perfusion of human skin. Heating increases local skin blood flow, but the mechanisms and mediators of this response (thermal hyperemia response) are incompletely elucidated. In the present study, we examined the possible dependence of the thermal hyperemia response on stimulation of muscarinic cholinergic receptors and on production of vasodilator prostanoids. In 13 male healthy subjects aged 20-30 yr, a temperature-controlled chamber was positioned on the volar face of one forearm and used to raise surface temperature from 34 to 41 degrees C. The time course of the resulting thermal hyperemia response was recorded with a laser-Doppler imager. In one experiment, each of eight subjects received an intravenous bolus of the antimuscarinic agent glycopyrrolate (4 microg/kg) on one visit and saline on the other. The thermal hyperemia response was determined within the hour after the injections. Glycopyrrolate effectively inhibited the skin vasodilation induced by iontophoresis of acetylcholine but did not influence the thermal hyperemia response. In a second experiment, conducted in five other subjects, 1 g of the cyclooxygenase inhibitor aspirin administered orally totally abolished the vasodilation induced in the skin by anodal current but also failed to modify the thermal hyperemia response. The present study excludes the stimulation of muscarinic receptors and the production of vasodilator prostaglandins as essential and nonredundant mechanisms for the vasodilation induced by local heating in human forearm skin.

  19. [Skin diseases in human immunodeficiency virus positive children from Santiago, Chile].

    PubMed

    Muñoz M, Paula; Gómez H, Oríetta; Luzoro V, Amaranta

    2008-08-01

    Children infected with human immunodeficiency virus (HIV) may develop severe, refractory mucocutaneous manifestations that may be the initiating symptom of HIV infection. In this study we examined the skin of all HIV positive children receiving medical care in the public health care system in Santiago, Chile. We detected mucocutaneous manifestations in 37/66 (56%) children from 7 months to 12 years of age. The most commonly encountered dermatologic manifestations were of infectious origin, mostly fungal (7.5%) and viral (7.5%) infections. With the increase in pediatric HIV patients worldwide, it is important to recognize skin manifestations of HIV positive children. This is the first published series of skin diseases in HIV positive children in Chile.

  20. Investigation of normal human skin tissue and acupuncture points of human skin tissue using fiberoptical FTIR spectroscopy

    NASA Astrophysics Data System (ADS)

    Brooks, Angelique L.; Bruch, Reinhard F.; Afanasyeva, Natalia I.; Kolyakov, Sergei F.; Butvina, Leonid N.; Ma, Lixing

    1998-06-01

    An innovative spectroscopic diagnostic method has been developed for investigation of different regions of normal human skin tissue. This new method is a combination of Fourier transform IR fiberoptic evanescent wave (FTIR-FEW) spectroscopy and fiber optic techniques for the middle IR (MIR) wavelength range. The fiber optical sensors we have used are characterized by low optical losses and high flexibility for remote analysis. Our fiber optical accessories and method allows for direct interaction of the skin tissue with the fiber probe and can be utilized with a diversity of standard commercial Fourier transform spectrometers. The FTIR-FEW technique, using nontoxic unclad fibers in the attenuated total reflection regime, is suitable for noninvasive, fast, sensitive investigations of normal skin in vivo for various medical diagnostics applications including studies of acupuncture points. Here we present the first data on IR spectra of skin tissue in vivo for normal skin and several acupuncture points in the range of 1300 to 1800 cm-1 and 2600 to 4000 cm-1.

  1. Decline of lymphatic vessel density and function in murine skin during aging.

    PubMed

    Karaman, Sinem; Buschle, Dorina; Luciani, Paola; Leroux, Jean-Christophe; Detmar, Michael; Proulx, Steven T

    2015-10-01

    Lymphatic vessels play important roles in the pathogenesis of many conditions that have an increased prevalence in the elderly population. However, the effects of the aging process on the lymphatic system are still relatively unknown. We have applied non-invasive imaging and whole-mount staining techniques to assess the lymphatic vessel function and morphology in three different age groups of mice: 2 months (young), 7 months (middle-aged), and 18 months (aged). We first developed and validated a new method to quantify lymphatic clearance from mouse ear skin, using a lymphatic-specific near-infrared tracer. Using this method, we found that there is a prominent decrease in lymphatic vessel function during aging since the lymphatic clearance was significantly delayed in aged mice. This loss of function correlated with a decreased lymphatic vessel density and a reduced lymphatic network complexity in the skin of aged mice as compared to younger controls. The blood vascular leakage in the skin was slightly increased in the aged mice, indicating that the decreased lymphatic function was not caused by a reduced capillary filtration in aged skin. The decreased function of lymphatic vessels with aging might have implications for the pathogenesis of a number of aging-related diseases.

  2. Transcriptome and ultrastructural changes in dystrophic Epidermolysis bullosa resemble skin aging.

    PubMed

    Breitenbach, Jenny S; Rinnerthaler, Mark; Trost, Andrea; Weber, Manuela; Klausegger, Alfred; Gruber, Christina; Bruckner, Daniela; Reitsamer, Herbert A; Bauer, Johann W; Breitenbach, Michael

    2015-06-01

    The aging process of skin has been investigated recently with respect to mitochondrial function and oxidative stress. We have here observed striking phenotypic and clinical similarity between skin aging and recessive dystrophic Epidermolysis bullosa (RDEB), which is caused by recessive mutations in the gene coding for collagen VII,COL7A1. Ultrastructural changes, defects in wound healing, and inflammation markers are in part shared with aged skin. We have here compared the skin transcriptomes of young adults suffering from RDEB with that of sex- and age-matched healthy probands. In parallel we have compared the skin transcriptome of healthy young adults with that of elderly healthy donors. Quite surprisingly, there was a large overlap of the two gene lists that concerned a limited number of functional protein families. Most prominent among the proteins found are a number of proteins of the cornified envelope or proteins mechanistically involved in cornification and other skin proteins. Further, the overlap list contains a large number of genes with a known role in inflammation. We are documenting some of the most prominent ultrastructural and protein changes by immunofluorescence analysis of skin sections from patients, old individuals, and healthy controls.

  3. Extracellular depolymerization of hyaluronic acid in cultured human skin fibroblasts

    SciTech Connect

    Nakamura, T.; Takagaki, K.; Kubo, K.; Morikawa, A.; Tamura, S.; Endo, M. )

    1990-10-15

    The chain length of ({sup 3}H)hyaluronic acid synthesized by cultivating human skin fibroblasts in the presence of ({sup 3}H)glucosamine was investigated. ({sup 3}H)Hyaluronic acid obtained from the matrix fraction was excluded from a Sepharose CL-2B column irrespective of the incubation period, whereas that from the medium was depolymerized into a constant chain length (Mr = 40,000). The reducing and non-reducing terminals of the depolymerized hyaluronic acid were N-acetylglucosamine and glucuronic acid, respectively. Prolonged incubation produced no oligosaccharides as shown by examination of hyaluronidase digests, suggesting the presence of a novel endo-beta-N-acetylglucosaminidase in cultured human skin fibroblasts.

  4. Comparison of in vivo and ex vivo laser scanning microscopy and multiphoton tomography application for human and porcine skin imaging

    NASA Astrophysics Data System (ADS)

    Darvin, M. E.; Richter, H.; Zhu, Y. J.; Meinke, M. C.; Knorr, F.; Gonchukov, S. A.; Koenig, K.; Lademann, J.

    2014-07-01

    Two state-of-the-art microscopic optical methods, namely, confocal laser scanning microscopy in the fluorescence and reflectance regimes and multiphoton tomography in the autofluorescence and second harmonic generation regimes, are compared for porcine skin ex vivo and healthy human skin in vivo. All skin layers such as stratum corneum (SC), stratum spinosum (SS), stratum basale (SB), papillary dermis (PD) and reticular dermis (RD) as well as transition zones between these skin layers are measured noninvasively at a high resolution, using the above mentioned microscopic methods. In the case of confocal laser scanning microscopy (CLSM), measurements in the fluorescence regime were performed by using a fluorescent dye whose topical application on the surface is well suited for the investigation of superficial SC and characterisation of the skin barrier function. For investigations of deeply located skin layers, such as SS, SB and PD, the fluorescent dye must be injected into the skin, which markedly limits fluorescence measurements using CLSM. In the case of reflection CLSM measurements, the obtained results can be compared to the results of multiphoton tomography (MPT) for all skin layers excluding RD. CLSM cannot distinguish between dermal collagen and elastin measuring their superposition in the RD. By using MPT, it is possible to analyse the collagen and elastin structures separately, which is important for the investigation of anti-aging processes. The resolution of MPT is superior to CLSM. The advantages and limitations of both methods are discussed and the differences and similarities between human and porcine skin are highlighted.

  5. Comparison of in vivo and ex vivo laser scanning microscopy and multiphoton tomography application for human and porcine skin imaging

    SciTech Connect

    Darvin, M E; Richter, H; Zhu, Y J; Meinke, M C; Knorr, F; Lademann, J; Gonchukov, S A; Koenig, K

    2014-07-31

    Two state-of-the-art microscopic optical methods, namely, confocal laser scanning microscopy in the fluorescence and reflectance regimes and multiphoton tomography in the autofluorescence and second harmonic generation regimes, are compared for porcine skin ex vivo and healthy human skin in vivo. All skin layers such as stratum corneum (SC), stratum spinosum (SS), stratum basale (SB), papillary dermis (PD) and reticular dermis (RD) as well as transition zones between these skin layers are measured noninvasively at a high resolution, using the above mentioned microscopic methods. In the case of confocal laser scanning microscopy (CLSM), measurements in the fluorescence regime were performed by using a fluorescent dye whose topical application on the surface is well suited for the investigation of superficial SC and characterisation of the skin barrier function. For investigations of deeply located skin layers, such as SS, SB and PD, the fluorescent dye must be injected into the skin, which markedly limits fluorescence measurements using CLSM. In the case of reflection CLSM measurements, the obtained results can be compared to the results of multiphoton tomography (MPT) for all skin layers excluding RD. CLSM cannot distinguish between dermal collagen and elastin measuring their superposition in the RD. By using MPT, it is possible to analyse the collagen and elastin structures separately, which is important for the investigation of anti-aging processes. The resolution of MPT is superior to CLSM. The advantages and limitations of both methods are discussed and the differences and similarities between human and porcine skin are highlighted. (laser biophotonics)

  6. Protective effect of porphyra-334 on UVA-induced photoaging in human skin fibroblasts.

    PubMed

    Ryu, Jina; Park, Su-Jin; Kim, In-Hye; Choi, Youn Hee; Nam, Taek-Jeong

    2014-09-01

    The significant increase in life expectancy is closely related to the growing interest in the impact of aging on the function and appearance of the skin. Skin aging is influenced by several factors, and solar ultraviolet (UV) irradiation is considered one of the most important causes of skin photoaging. The aim of this study was to examine the anti-photoaging role of porphyra-334 from Porphyra (P.) yezoensis, a mycosporine-like amino acid (MAA), using high-performance liquid chromatography (HPLC), and electrospray ionization‑mass spectrometry (ESI-MS). In the present study, extracted UV‑absorbing compounds from P. yezoensis included palythine, asterina-330 and porphyra-334. Porphyra-334 was the most abundant MAA in P. yezoensis, and it was therefore used for conducting antiphotoaging experiments. The effect of porphyra-334 on the prevention of photoaging was investigated by measuring reactive oxygen species (ROS) production and matrix metalloproteinase (MMP) levels, as well as extracellular matrix (ECM) components and protein expression in UVA‑irradiated human skin fibroblasts. Porphyra-334 suppressed ROS production and the expression of MMPs following UVA irradiation, while increasing levels of ECM components, such as procollagen, type I collagen, elastin. These results suggest that porphyra-334 has various applications in cosmetics and toiletries because of its anti‑photoaging activities and may serve as a novel anti-aging agent.

  7. Dietary water affects human skin hydration and biomechanics

    PubMed Central

    Palma, Lídia; Marques, Liliana Tavares; Bujan, Julia; Rodrigues, Luís Monteiro

    2015-01-01

    It is generally assumed that dietary water might be beneficial for the health, especially in dermatological (age preventing) terms. The present study was designed to quantify the impact of dietary water on major indicators of skin physiology. A total of 49 healthy females (mean 24.5±4.3 years) were selected and characterized in terms of their dietary daily habits, especially focused in water consumption, by a Food Frequency Questionnaire. This allowed two groups to be set – Group 1 consuming less than 3,200 mL/day (n=38), and Group 2 consuming more than 3,200 mL/day (n=11). Approximately 2 L of water were added to the daily diet of Group 2 individuals for 1 month to quantify the impact of this surplus in their skin physiology. Measurements involving epidermal superficial and deep hydration, transepidermal water loss, and several biomechanical descriptors were taken at day 0 (T0), 15 (T1), and 30 (T2) in several anatomical sites (face, upper limb, and leg). This stress test (2 L/day for 30 days) significantly modified superficial and deep skin hydration, especially in Group 1. The same impact was registered with the most relevant biomechanical descriptors. Thus, in this study, it is clear that higher water inputs in regular diet might positively impact normal skin physiology, in particular in those individuals with lower daily water consumptions. PMID:26345226

  8. Development of an innervated model of human skin.

    PubMed

    Khammo, Nancy; Ogilvie, Jane; Clothier, Richard H

    2007-10-01

    Neuronal cell responses and interactions with the epithelial and fibroblastic cells of the skin are a key factor in the production in vivo of the irritation/inflammatory response. Currently, few in vitro models are available that contain dermal, epidermal and the relevant neuronal components. The primary objective of this study was to produce and maintain a 3-D in vitro model of human skin containing these elements. The relevant neuronal component was supplied by adding sensory neurons derived from the dorsal root ganglion (DRG). Since adult neuronal cells do not grow significantly in vivo or in vitro, and since it is very difficult to obtain such cells from humans, it was necessary to employ embryonic rat DRG cells. The ultimate purpose of this model is to improve prediction of the in vivo skin irritancy potential of chemicals and formulations, without the need to use animal models. In addition, this approach has also been applied to the in vitro human eye and bronchial 3-D models being developed in the FRAME Alternatives Laboratory.

  9. Noninvasive topographical investigation of functional parameters in the human skin

    NASA Astrophysics Data System (ADS)

    Kessler, Manfred D.; Krug, Alfons; Hoeper, Jens

    1996-04-01

    A rapid micro-lightguide spectrometer (EMPHO II) coupled to an automatic three axis positioning system enables very precise and fast 2D-scans at the surface of human skin. The positioning accuracy amounts to 1 micrometer. This allows measurements with excellent spatial reproducibility. With this system examinations of local distribution of HbO2 and Hb have been performed in human skin. For this purpose at the back of the hand areas of 5 by 5 mm to 5 by 10 mm were scanned in defined steps of 100 micrometers. Functional images of local hemoglobin concentration and hemoglobin oxygenation of microscopical structures have been resolved by use of 250 micrometer lightguide sensors. Two-dimensional-images of local oxygen supply parameters corresponding directly to morphological structures of human skin have been gained. The local pattern matches the distribution of the papillas of the corium. In the papillas the capillary loops supplying the lower part of the epidermis are situated. The measured parameters describe very exactly the local oxygen supply situation of the area under investigation.

  10. Biogeography and individuality shape function in the human skin metagenome

    PubMed Central

    Oh, Julia; Byrd, Allyson L.; Deming, Clay; Conlan, Sean; Kong, Heidi H.; Segre, Julia A.

    2014-01-01

    Summary The varied topography of human skin offers a unique opportunity to study how the body’s microenvironments influence the functional and taxonomic composition of microbial communities. Phylogenetic marker gene-based studies have identified many bacteria and fungi that colonize distinct skin niches. Here, metagenomic analyses of diverse body sites in healthy humans demonstrate that local biogeography and strong individuality define the skin microbiome. We developed a relational analysis of bacterial, fungal, and viral communities, which showed not only site-specificity but also individual signatures. We further identified strain-level variation of dominant species as heterogeneous and multiphyletic. Reference-free analyses captured the uncharacterized metagenome through the development of a multi-kingdom gene catalog, which was used to uncover genetic signatures of species lacking reference genomes. This work is foundational for human disease studies investigating inter-kingdom interactions, metabolic changes, and strain tracking and defines the dual influence of biogeography and individuality on microbial composition and function. PMID:25279917

  11. Is lack of sleep capable of inducing DNA damage in aged skin?

    PubMed

    Kahan, V; Ribeiro, D A; Egydio, F; Barros, L A; Tomimori, J; Tufik, S; Andersen, M L

    2014-01-01

    Skin naturally changes with age, becoming more fragile. Various stimuli can alter skin integrity. The aim of this study was to evaluate whether sleep deprivation affects the integrity of DNA in skin and exacerbates the effects of aging. Fifteen-month old female Hairless mice underwent 72 h of paradoxical sleep deprivation or 15 days of chronic sleep restriction. Punch biopsies of the skin were taken to evaluate DNA damage by single cell gel (comet) assay. Neither paradoxical sleep deprivation nor sleep restriction increased genetic damage, measured by tail movement and tail intensity values. Taken together, the findings are consistent with the notion that aging overrides the effect of sleep loss on the genetic damage in elderly mice.

  12. Anticedants and natural prevention of environmental toxicants induced accelerated aging of skin.

    PubMed

    Tanuja Yadav; Mishra, Shivangi; Das, Shefali; Aggarwal, Shikha; Rani, Vibha

    2015-01-01

    Skin is frequently exposed to a variety of environmental and chemical agents that accelerate ageing. External stress such as UV radiations (UVR) and environmental pollutants majorly deteriorate the skin morphology, by activating certain intrinsic factors such as Reactive Oxygen Species (ROS) which trigger the activation of Matrix Metalloproteinases (MMPs) and inflammatory responses hence damaging the extracellular matrix (ECM) components. To counter this, an exogenous supply of anti-oxidants, is required since the endogenous anti-oxidant system cannot alone suffice the need. Bio-prospecting of natural resources for anti-oxidants has hence been intensified. Immense research is being carried out to identify potential plants with potent anti-oxidant activity against skin ageing. This review summarizes the major factors responsible for premature skin ageing and the plants being targeted to lessen the impact of those.

  13. Differences in tooth shade value according to age, gender and skin color: A pilot study

    PubMed Central

    Veeraganta, Sumanth K.; Savadi, Ravindra C.; Baroudi, Kusai; Nassani, Mohammad Z.

    2015-01-01

    Purpose of the Study: The purpose was to investigate the differences in tooth shade value according to age, gender and skin color among a sample of the local population in Bengaluru, India. Methodology: The study comprised 100 subjects belonging to both gender between the age groups of 16 years to 55 years. Tooth shade values of permanent maxillary left or right central incisors were recorded using the Vitapan 3D-Master shade guide. Skin color was matched using the Radiance compact makeup shades as a guide. Results: Chi-square statistical test demonstrated that younger subjects have lighter tooth shade values. No statistically significant differences were recorded in tooth shade value according to gender or skin color. Conclusion: Within the limitations of the current study, it can be concluded that tooth shade value is significantly influenced by age. Gender and skin color appear not to have a significant relation to tooth shade value. PMID:26929500

  14. The underlying mechanism of proinflammatory NF-κB activation by the mTORC2/Akt/IKKα pathway during skin aging

    PubMed Central

    Choi, Yeon Ja; Moon, Kyoung Mi; Chung, Ki Wung; Jeong, Ji Won; Park, Daeui; Kim, Dae Hyun; Yu, Byung Pal; Chung, Hae Young

    2016-01-01

    Mammalian target of rapamycin complex 2 (mTORC2), one of two different enzymatic complexes of mTOR, regulates a diverse set of substrates including Akt. mTOR pathway is one of well-known mediators of aging process, however, its role in skin aging has not been determined. Skin aging can be induced by physical age and ultraviolet (UV) irradiation which are intrinsic and extrinsic factors, respectively. Here, we report increased mTORC2 pathway in intrinsic and photo-induced skin aging, which is implicated in the activation of nuclear factor-κB (NF-κB). UVB-irradiated or aged mice skin revealed that mTORC2 activity and its component, rictor were significantly upregulated which in turn increased Akt activation and Akt-dependent IκB kinase α (IKKα) phosphorylation at Thr23 in vivo. We also confirmed that UVB induced the mTORC2/Akt/IKKα signaling pathway with HaCaT human normal keratinocytes. The increased mTORC2 signaling pathway during skin aging were associated to NF-κB activation. Suppression of mTORC2 activity by the treatment of a mTOR small inhibitor or knockdown of RICTOR partially rescued UVB-induced NF-κB activation through the downregulation of Akt/IKKα activity. Our data demonstrated the upregulation of mTORC2 pathway in intrinsic and photo-induced skin aging and its role in IKKα/NF-κB activation. These data not only expanded the functions of mTOR to skin aging but also revealed the therapeutic potential of inhibiting mTORC2 in ameliorating both intrinsic skin aging and photoaging. PMID:27486771

  15. In-vivo differentiation of photo-aged epidermis skin by texture-based classification

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaoman; Weng, Cuncheng; Yu, Biying; Li, Hui

    2014-11-01

    Two sets of in vivo female cheek skin epidermis images were analyzed through gray level co-occurrence matrix (GLCM) and fast fourier transform (FFT). One set was derived from women in their 20s and the other from women more than 60 years of age. GLCM was used to evaluate the texture features of the regions of interest within the cheek epidermis, and texture classification was subsequently performed. During texture classification, 25 images (320×240 pixels) in each age set were randomly selected. Three texture features, i.e., energy, contrast, and correlation, were obtained from the skin images and analyzed at four orientations (0°, 45°,90°, and 135°), accompanied by different distances between two pixels. The textures of the different aging skins were characterized by FFT, which provides the dermatoglyph orientation index. The differences in the textures between the young and old skin samples can be well described by the FFT dermatoglyph orientation index. The texture features varied among the different aging skins, which provide a versatile platform for differentiating the statuses of aging skins.

  16. Objective assessment of facial skin aging and the associated environmental factors in Japanese monozygotic twins.

    PubMed

    Ichibori, Ryoko; Fujiwara, Takashi; Tanigawa, Tomoko; Kanazawa, Shigeyuki; Shingaki, Kenta; Torii, Kosuke; Tomita, Koichi; Yano, Kenji; Sakai, Yasuo; Hosokawa, Ko

    2014-06-01

    Twin studies, especially those involving monozygotic (MZ) twins, facilitate the analysis of factors affecting skin aging while controlling for age, gender, and genetic susceptibility. The purpose of this study was to objectively assess various features of facial skin and analyze the effects of environmental factors on these features in MZ twins. At the Osaka Twin Research Center, 67 pairs of MZ twins underwent medical interviews and photographic assessments, using the VISIA(®) Complexion Analysis System. First, the average scores of the right and left cheek skin spots, wrinkles, pores, texture, and erythema were calculated; the differences between the scores were then compared in each pair of twins. Next, using the results of medical interviews and VISIA data, we investigated the effects of environmental factors on skin aging. The data were analyzed using Pearson's correlation coefficient test and the Wilcoxon signed-rank test. The intrapair differences in facial texture scores significantly increased as the age of the twins increased (P = 0.03). Among the twin pairs who provided answers to the questions regarding history differences in medical interviews, the twins who smoked or did not use skin protection showed significantly higher facial texture or wrinkle scores compared with the twins not exposed to cigarettes or protectants (P = 0.04 and 0.03, respectively). The study demonstrated that skin aging among Japanese MZ twins, especially in terms of facial texture, was significantly influenced by environmental factors. In addition, smoking and skin protectant use were important environmental factors influencing skin aging.

  17. Gene expression changes with age in skin, adipose tissue, blood and brain

    PubMed Central

    2013-01-01

    Background Previous studies have demonstrated that gene expression levels change with age. These changes are hypothesized to influence the aging rate of an individual. We analyzed gene expression changes with age in abdominal skin, subcutaneous adipose tissue and lymphoblastoid cell lines in 856 female twins in the age range of 39-85 years. Additionally, we investigated genotypic variants involved in genotype-by-age interactions to understand how the genomic regulation of gene expression alters with age. Results Using a linear mixed model, differential expression with age was identified in 1,672 genes in skin and 188 genes in adipose tissue. Only two genes expressed in lymphoblastoid cell lines showed significant changes with age. Genes significantly regulated by age were compared with expression profiles in 10 brain regions from 100 postmortem brains aged 16 to 83 years. We identified only one age-related gene common to the three tissues. There were 12 genes that showed differential expression with age in both skin and brain tissue and three common to adipose and brain tissues. Conclusions Skin showed the most age-related gene expression changes of all the tissues investigated, with many of the genes being previously implicated in fatty acid metabolism, mitochondrial activity, cancer and splicing. A significant proportion of age-related changes in gene expression appear to be tissue-specific with only a few genes sharing an age effect in expression across tissues. More research is needed to improve our understanding of the genetic influences on aging and the relationship with age-related diseases. PMID:23889843

  18. Dynamic viscoelastic models of human skin using optical elastography

    PubMed Central

    Kearney, Steven P.; Khan, Altaf; Dai, Zoujun; Royston, Thomas J.

    2015-01-01

    A novel technique for measuring in vivo human skin viscoelastic properties using optical elastography has been developed. The technique uses geometrically focused surface (GFS) waves that allow for wide bandwidth measurements of the wave field. An analytical solution for the case of a radiating annular disk surface source was fit to experimentally measured GFS waves, enabling an estimate of the frequency-dependent surface wavenumber, which can then be related to the dynamic shear modulus. Several viscoelastic models were then fit to the dynamic shear modulus dispersion curve. Viscoelastic models were evaluated based on their overall quality of fit and variability amongst healthy volunteers. An Ecoflex phantom was used to validate the procedure and results by comparison to similar studies using the same type of phantom. For skin results, it was found that the “α” parameters from the fractional models had the least variability, with coefficients of variability of 0.15, and 0.16. The best fitting models were the standard linear solid, and the fractional Voigt, with a mean fit correlation coefficient, R2, of 0.93, 0.89, respectively. This study has demonstrated the efficacy of this new method, and with larger studies the viscoelastic skin models could be used to identify various skin diseases and their response to treatment. PMID:26305137

  19. Distribution of bioactive lipid mediators in human skin.

    PubMed

    Kendall, Alexandra C; Pilkington, Suzanne M; Massey, Karen A; Sassano, Gary; Rhodes, Lesley E; Nicolaou, Anna

    2015-06-01

    The skin produces bioactive lipids that participate in physiological and pathological states, including homeostasis, induction, propagation, and resolution of inflammation. However, comprehension of the cutaneous lipid complement, and contribution to differing roles of the epidermal and dermal compartments, remains incomplete. We assessed the profiles of eicosanoids, endocannabinoids, N-acyl ethanolamides, and sphingolipids, in human dermis, epidermis, and suction blister fluid. We identified 18 prostanoids, 12 hydroxy-fatty acids, 9 endocannabinoids and N-acyl ethanolamides, and 21 non-hydroxylated ceramides and sphingoid bases, several demonstrating significantly different expression in the tissues assayed. The array of dermal and epidermal fatty acids was reflected in the lipid mediators produced, whereas similarities between lipid profiles in blister fluid and epidermis indicated a primarily epidermal origin of suction blister fluid. Supplementation with omega-3 fatty acids ex vivo showed that their action is mediated through perturbation of existing species and formation of other anti-inflammatory lipids. These findings demonstrate the diversity of lipid mediators involved in maintaining tissue homeostasis in resting skin and hint at their contribution to signaling, cross-support, and functions of different skin compartments. Profiling lipid mediators in biopsies and suction blister fluid can support studies investigating cutaneous inflammatory responses, dietary manipulation, and skin diseases lacking biomarkers and therapeutic targets.

  20. Modeling and analysis of cosmetic treatment effects on human skin

    NASA Astrophysics Data System (ADS)

    Lunderstaedt, Reinhart A.; Hopermann, Hermann; Hillemann, Thomas

    2000-10-01

    In view of treatment effects of cosmetics, quality management becomes more and more important. Due to the efficiency reasons it is desirable to quantify these effects and predict them as a function of time. For this, a mathematical model of the skin's surface (epidermis) is needed. Such a model cannot be worked out purely analytically. It can only be derived with the help of measurement data. The signals of interest as output of different measurement devices consist of two parts: noise of high (spatial) frequencies (stochastic signal) and periodic functions (deterministic signal) of low (spatial) frequencies. Both parts can be separated by correlation analysis. The paper introduces in addition to the Fourier Transform (FT) with the Wavelet Transform (WT), a brand new, highly sophisticated method with excellent properties for both modeling the skin's surface as well as evaluating treatment effects. Its main physical advantage is (in comparison to the FT) that local irregularities in the measurement signal (e.g. by scars) remain at their place and are not represented as mean square values as it is the case when applying the FT. The method has just now been installed in industry and will there be used in connection with a new in vivo measurement device for quality control of cosmetic products. As texture parameter for an integral description of the human skin the fractal dimension D is used which is appropriate for classification of different skin regions and treatment effects as well.

  1. Spectral analysis of laser Doppler skin blood flow oscillations in human essential arterial hypertension.

    PubMed

    Rossi, Marco; Carpi, Angelo; Di Maria, Cinzia; Galetta, Fabio; Santoro, Gino

    2006-01-01

    The aim of this study was to investigate whether human essential arterial hypertension (EHT) is associated with modification of the skin blood flowmotion (SBF), which could be a sign of skin microcirculatory impairment. Forearm skin perfusion was measured by laser Doppler flowmetry (LDF) in conventional perfusion units (PU) before and after ischemia in 20 middle-age newly diagnosed EHT untreated patients, in 20 middle-age long standing EHT treated patients and in 30 age and sex matched healthy normotensive subjects (NS). Power spectral density (PSD) of SBF total spectrum (0.009-1.6 Hz), as well of five different frequency intervals (FI), each of them related to endothelial (0.009-0.02 Hz), sympathetic (0.02-0.06 Hz), myogenic (0.06-0.2 Hz), respiratory (0.2-0.6) or cardiac (0.6-1.6) activity, was also measured in PU(2)/Hz before and after ishemia, using Fourier analysis of LDF signal. The three studied groups did not differ in basal and post-ischemic skin perfusion or in basal SBF parameters considered. However, while a significant post-ischemic increase in PSD of total spectrum SBF (P < 0.001) and of its different FI, with the only exception of respiratory FI, was observed in NS, a significsnt post-ischemic increase in PSD was observed only for total spectrum (P < 0.01) and for endothelial FI (P < 0.001) in newly diagnosed EHT patients and only for myogenic FI (P < 0.05) in long standing EHT patients. These findings suggest that the mechanisms which mediate the post-ischemic increment of SBF are perturbed earlier in human EHT than the mechanisms which mediate the skin post-ischemic hyperaemia. The same findings also suggest that the impairment of the endothelial mechanism involved in SBF control occurs by the time in the course of EHT.

  2. Adherence of skin bacteria to human epithelial cells.

    PubMed Central

    Romero-Steiner, S; Witek, T; Balish, E

    1990-01-01

    Aerobic and anaerobic bacteria isolated from human axillae were tested for their capacity to adhere to buccal epithelial cells, immortalized human epithelial (HEp-2) cells, and undifferentiated and differentiated human epithelial cells. In general, both aerobic and anaerobic diphtheroids adhered better to differentiated human epithelial cells than to HEp-2 and undifferentiated human epithelial cells (P less than 0.05). Mannose, galactose, fucose, N-acetyl-D-glucosamine, and fibronectin were also assayed for their capacity to inhibit the adherence of diphtheroids to human epithelial cells. A great deal of variability was observed in the capacity of the latter compounds to inhibit the attachment of aerobic diphtheroids to undifferentiated and differentiated epithelial cells. Overall, mannose appeared to be best at inhibiting the adherence of the aerobic diphtheroids to undifferentiated human epithelial cells. Galactose, fucose, N-acetyl-D-glucosamine, and fibronectin showed a greater capacity to inhibit attachment of aerobic diphtheroids to differentiated than to undifferentiated human epithelial cells. The inhibition of adherence to differentiated human epithelial cells varied with the microorganism and the compound tested; however, the highest and most consistent inhibition of adherence (76.1 to 88.6%) was observed with a 5% solution of N-acetyl-D-glucosamine. The in vitro adherence and adherence inhibition assays presented here demonstrate that a number of adhesins and receptors are involved in the adherence of skin bacteria to human epithelial cells and receptors on human epithelial cells are apparently altered during differentiation. PMID:2298877

  3. Skin care in the aging female: myths and truths

    PubMed Central

    Neill, Ushma S.

    2012-01-01

    I recently had the opportunity to visit a very relaxing and beautiful day spa during the middle-of-the-day break from the sessions at a Keystone meeting. I was having a very tranquil and restorative day, when I went in for my final treatment — a facial. The very chipper and cheerful esthetician began examining my skin and applying various creams, when I then heard her say something that nearly ruined my experience: she claimed that the topical treatment she was about to apply would, in her words, “cleanse my liver.” PMID:22293186

  4. In vitro model adapted to the study of skin ageing induced by air pollution.

    PubMed

    Lecas, Sarah; Boursier, Elsa; Fitoussi, Richard; Vié, Katell; Momas, Isabelle; Seta, Nathalie; Achard, Sophie

    2016-09-30

    More than a barrier against environmental agents, skin reflects individual health and is a visible sign of ageing with the progressive loss of skin integrity. In order to evaluate the consequences of an environmental complex mixture, with tobacco smoke (TS) as model, on cellular and morphological changes, a 3D skin model was used. Morphologically, tissue integrity was intact after one TS-exposure while the superficial layers were drastically reduced after two TS-exposures. However, TS modified epidermal organisation at the molecular level after just one exposure. A decrease in loricrin protein staining was showed in the epidermis, while production of inflammatory cytokines (IL-8, IL-1α, IL-18) and metalloproteinase (MMP-1, MMP-3) were stimulated. Oxidative stress was also illustrated with an increase in 4-HNE protein staining. Moreover, terminal differentiation, cell-cell junction and anchorage gene expression was down-regulated in our model after one TS-exposure. In conclusion, tobacco smoke impacted the fundamental functions of skin, namely tissue anchorage, cornification and skin desquamation. Oxidative stress resulted in skin ageing. The tissue was even reactive with the inflammatory pathways, after one TS-exposure. The 3D-RHE model is appropriate for evaluating the impact of environmental pollutants on skin ageing.

  5. Transcriptome and ultrastructural changes in dystrophic Epidermolysis bullosa resemble skin aging

    PubMed Central

    Trost, Andrea; Weber, Manuela; Klausegger, Alfred; Gruber, Christina; Bruckner, Daniela; Reitsamer, Herbert A.; Bauer, Johann W.; Breitenbach, Michael

    2015-01-01

    The aging process of skin has been investigated recently with respect to mitochondrial function and oxidative stress. We have here observed striking phenotypic and clinical similarity between skin aging and recessive dystrophic Epidermolysis bullosa (RDEB), which is caused by recessive mutations in the gene coding for collagen VII, COL7A1. Ultrastructural changes, defects in wound healing, and inflammation markers are in part shared with aged skin. We have here compared the skin transcriptomes of young adults suffering from RDEB with that of sex‐ and age‐matched healthy probands. In parallel we have compared the skin transcriptome of healthy young adults with that of elderly healthy donors. Quite surprisingly, there was a large overlap of the two gene lists that concerned a limited number of functional protein families. Most prominent among the proteins found are a number of proteins of the cornified envelope or proteins mechanistically involved in cornification and other skin proteins. Further, the overlap list contains a large number of genes with a known role in inflammation. We are documenting some of the most prominent ultrastructural and protein changes by immunofluorescence analysis of skin sections from patients, old individuals, and healthy controls. PMID:26143532

  6. Athletic equipment microbiota are shaped by interactions with human skin

    DOE PAGES

    Wood, Mariah; Gibbons, Sean M.; Lax, Simon; ...

    2015-06-19

    Background: Americans spend the vast majority of their lives in built environments. Even traditionally outdoor pursuits, such as exercising, are often now performed indoors. Bacteria that colonize these indoor ecosystems are primarily derived from the human microbiome. The modes of human interaction with indoor surfaces and the physical conditions associated with each surface type determine the steady-state ecology of the microbial community. Results: Bacterial assemblages associated with different surfaces in three athletic facilities, including floors, mats, benches, free weights, and elliptical handles, were sampled every other hour (8 am to 6 pm) for 2 days. Surface and equipment type hadmore » a stronger influence on bacterial community composition than the facility in which they were housed. Surfaces that were primarily in contact with human skin exhibited highly dynamic bacterial community composition and non-random co-occurrence patterns, suggesting that different host microbiomes—shaped by selective forces—were being deposited on these surfaces through time. Bacterial assemblages found on the floors and mats changed less over time, and species co-occurrence patterns appeared random, suggesting more neutral community assembly. Conclusions: These longitudinal patterns highlight the dramatic turnover of microbial communities on surfaces in regular contact with human skin. By uncovering these longitudinal patterns, this study promotes a better understanding of microbe-human interactions within the built environment.« less

  7. Athletic equipment microbiota are shaped by interactions with human skin

    SciTech Connect

    Wood, Mariah; Gibbons, Sean M.; Lax, Simon; Eshoo-Anton, Tifani W.; Owens, Sarah M.; Kennedy, Suzanne; Gilbert, Jack A.; Hampton-Marcell, Jarrad T.

    2015-06-19

    Background: Americans spend the vast majority of their lives in built environments. Even traditionally outdoor pursuits, such as exercising, are often now performed indoors. Bacteria that colonize these indoor ecosystems are primarily derived from the human microbiome. The modes of human interaction with indoor surfaces and the physical conditions associated with each surface type determine the steady-state ecology of the microbial community. Results: Bacterial assemblages associated with different surfaces in three athletic facilities, including floors, mats, benches, free weights, and elliptical handles, were sampled every other hour (8 am to 6 pm) for 2 days. Surface and equipment type had a stronger influence on bacterial community composition than the facility in which they were housed. Surfaces that were primarily in contact with human skin exhibited highly dynamic bacterial community composition and non-random co-occurrence patterns, suggesting that different host microbiomes—shaped by selective forces—were being deposited on these surfaces through time. Bacterial assemblages found on the floors and mats changed less over time, and species co-occurrence patterns appeared random, suggesting more neutral community assembly. Conclusions: These longitudinal patterns highlight the dramatic turnover of microbial communities on surfaces in regular contact with human skin. By uncovering these longitudinal patterns, this study promotes a better understanding of microbe-human interactions within the built environment.

  8. Liposomes encapsulating Aloe vera leaf gel extract significantly enhance proliferation and collagen synthesis in human skin cell lines.

    PubMed

    Takahashi, Makoto; Kitamoto, Dai; Asikin, Yonathan; Takara, Kensaku; Wada, Koji

    2009-01-01

    Aloe vela leaf gel extract (AGE) are widely used as cosmetic and pharmaceutical ingredients because of its versatile skin care properties. In order to enhance the bioavailability of AGE, liposomes encapsulating AGE were prepared and examined for their interfacial and biochemical properties. The liposomes prepared from a soybean lecithin (SLP-WHITE, 1.0 wt%) by the Bangham method gave relatively a good trapping efficiency up to the AGE concentration of 0.5 wt%. The stable liposomes were then prepared from 1.0 wt% of SLP-WHITE and different concentrations of AGE by the mechanochemical method using a homogenizer and microfluidizer. The liposomes obtained from 0.25 wt% of AGE were confirmed to be small unilamellar vesicles with a diameter of less than 200 nm, and remained well dispersed for at least two weeks. The obtained liposomes encapsulating AGE were further examined for the effects on proliferation and type I collagen synthesis in normal human neonatal skin fibroblasts, NB1RGB cells. Liposomal AGE clearly showed higher proliferation rate than that of AGE alone. In addition, compared to the control, liposomal AGE significantly increased the collagen synthesis by 23%, while AGE alone showed a small effect. Liposomal AGE was also assayed for the effect on proliferation in normal human epidermal keratinocytes, NHEK(F) cells. Interestingly, liposomal AGE fractions containing 4 and 20 microg/mL of the extract considerably increased the proliferation rate by 77% and 101%, respectively. In contrast, AGE alone fractions containing 4 and 20 microg/mL of the extract increased the rate by 41% and 60%, respectively. Accordingly, the bioavailability and skin care properties of AGE will be significantly enhanced by liposome encapsulation, and the present liposomal AGE should have a great potential as an effective skin care formulation.

  9. Protein oxidative damage and heme oxygenase in sunlight-exposed human skin: roles of MAPK responses to oxidative stress.

    PubMed

    Akasaka, Emiko; Takekoshi, Susumu; Horikoshi, Yosuke; Toriumi, Kentarou; Ikoma, Norihiro; Mabuchi, Tomotaka; Tamiya, Shiho; Matsuyama, Takashi; Ozawa, Akira

    2010-12-20

    Oxidative stress derived from ultraviolet (UV) light in sunlight induces different hazardous effects in the skin, including sunburn, photo-aging and DNA mutagenesis. In this study, the protein-bound lipid peroxidation products 4-hydroxy-2-nonenal (HNE) and the oxidative DNA damage marker 8-hydroxy-2'-deoxyguanosine (8OHdG) were investigated in chronically sun-exposed and sun-protected human skins using immunohistochemistry. The levels of antioxidative enzymes, such as heme oxygenase 1 and 2, Cu/Zn-SOD, Mn-SOD and catalase, were also examined. Oxidative stress is also implicated in the activation of signal transduction pathways, such as mitogen-activated protein kinase (MAPK). Therefore, the expression and distribution of phosphorylated p38 MAPK, phosphorylated Jun N-terminal kinase (JNK) and phosphorylated extracellular signal-regulated kinase (ERK) were observed. Skin specimens were obtained from the surgical margins. Chronically sunlight-exposed skin samples were taken from the ante-auricular (n = 10) and sunlight-protected skin samples were taken from the post-auricular (n = 10). HNE was increased in the chronically sunlight-exposed skin but not in the sunlight-protected skin. The expression of heme oxygenase-2 was markedly increased in the sunlight-exposed skin compared with the sun-protected skin. In contrast, the intensity of immunostaining of Cu/Zn-SOD, Mn-SOD and catalase was not different between the two areas. Phosphorylated p38 MAPK and phosphorylated JNK accumulated in the ante-auricular dermis and epidermis, respectively. These data show that particular anti-oxidative enzymes function as protective factors in chronically sunlight-exposed human skin. Taken together, our results suggest (1) antioxidative effects of heme oxygenase-2 in chronically sunlight-exposed human skin, and that (2) activation of p38 MAPK may be responsible for oxidative stress.

  10. Variation of Biophysical Parameters of the Skin with Age, Gender, and Body Region

    PubMed Central

    Firooz, Alireza; Sadr, Bardia; Babakoohi, Shahab; Sarraf-Yazdy, Maryam; Fanian, Ferial; Kazerouni-Timsar, Ali; Nassiri-Kashani, Mansour; Naghizadeh, Mohammad Mehdi; Dowlati, Yahya

    2012-01-01

    Background. Understanding the physiological, chemical, and biophysical characteristics of the skin helps us to arrange a proper approach to the management of skin diseases. Objective. The aim of this study was to measure 6 biophysical characteristics of normal skin (sebum content, hydration, transepidermal water loss (TEWL), erythema index, melanin index, and elasticity) in a normal population and assess the effect of sex, age, and body location on them. Methods. Fifty healthy volunteers in 5 age groups (5 males and females in each) were enrolled in this study. A multifunctional skin physiology monitor (Courage & Khazaka electronic GmbH, Germany) was used to measure skin sebum content, hydration, TEWL, erythema index, melanin index, and elasticity in 8 different locations of the body. Results. There were significant differences between the hydration, melanin index, and elasticity of different age groups. Regarding the locations, forehead had the highest melanin index, where as palm had the lowest value. The mean values of erythema index and melanin index and TEWL were significantly higher in males and anatomic location was a significant independent factor for all of 6 measured parameters. Conclusion. Several biophysical properties of the skin vary among different gender, age groups, and body locations. PMID:22536139

  11. Contribution of human skin topography to the characterization of dynamic skin tension during senescence: morpho-mechanical approach

    NASA Astrophysics Data System (ADS)

    Zahouani, H.; Djaghloul, M.; Vargiolu, R.; Mezghani, S.; Mansori, M. E. L.

    2014-03-01

    The structuring of the dermis with a network of collagen and elastic fibres gives a three-dimensional structure to the skin network with directions perpendicular and parallel to the skin surface. This three-dimensional morphology prints on the surface of the stratum corneum a three dimensional network of lines which express the mechanical tension of the skin at rest. To evaluate the changes of skin morphology, we used a three-dimensional confocal microscopy and characterization of skin imaging of volar forearm microrelief. We have accurately characterize the role of skin line network during chronological aging with the identification of depth scales on the network of lines (z <= 60μm) and the network of lines covering Langer's lines (z > 60 microns). During aging has been highlighted lower rows for elastic fibres, the decrease weakened the tension and results in enlargement of the plates of the microrelief, which gives us a geometric pertinent indicator to quantify the loss of skin tension and assess the stage of aging. The study of 120 Caucasian women shows that ageing in the volar forearm zone results in changes in the morphology of the line network organisation. The decrease in secondary lines (z <= 60 μm) is counterbalanced by an increase in the depth of the primary lines (z > 60 μm) and an accentuation of the anisotropy index.

  12. Human skin image analysis using coherent focused beam scattering

    NASA Astrophysics Data System (ADS)

    Zimnyakov, Dmitry A.; Tuchin, Valery V.; Utz, Sergei R.; Mishin, Alexey A.

    1995-02-01

    The analysis of statistical and correlation properties of speckle patterns formed during different skin tissue scanning by the sharply focused probing laser beam has been carried out. The influences of the biotissues' structural features on the speckle patterns formation under Gaussian beam illumination have been investigated. The relationships between the structural characteristics of the sample under study, Rayleigh range of the probing beam and normalized statistical moments of the speckle intensity (contrast and asymmetry coefficient) are discussed for the different scatterer models. A phenomenological model of speckle pattern formation for the large-scale scatterers allows us to explain the dependence of speckle contrast and the coefficient of asymmetry on the generalized structure parameters and illumination conditions for the samples under study. The experimental investigations of the human skin structure features have been carried out using two types of the tissue samples by means of coherent scanning microscopy (CSM). Firstly, D-SQUAME discs (CuDerm Corporation, Texas, USA) have been used for the evaluation of skin dryness level. Secondly, the samples under study were the thin layers of normal and psoriatic epidermis (skin strippings). The dependencies of contrast and coefficient of asymmetry on the beam defocusing parameter and 2D correlation functions of speckle pattern intensity have been analyzed for different zones on the biotissue's surface. Particularly, promising results in skin dryness studies (using D-SQUAME discs) have been obtained. Our results and conventional 5-pattern kit scale are in good agreement. So, the presented method is accurate and objective and may be useful in novel cosmetic research and development.

  13. Hyperspectral imaging for detection of cholesterol in human skin

    NASA Astrophysics Data System (ADS)

    Milanič, Matija; Bjorgan, Asgeir; Larsson, Marcus; Marraccini, Paolo; Strömberg, Tomas; Randeberg, Lise L.

    2015-03-01

    Hypercholesterolemia is characterized by high levels of cholesterol in the blood and is associated with an increased risk of atherosclerosis and coronary heart disease. Early detection of hypercholesterolemia is necessary to prevent onset and progress of cardiovascular disease. Optical imaging techniques might have a potential for early diagnosis and monitoring of hypercholesterolemia. In this study, hyperspectral imaging was investigated for this application. The main aim of the study was to identify spectral and spatial characteristics that can aid identification of hypercholesterolemia in facial skin. The first part of the study involved a numerical simulation of human skin affected by hypercholesterolemia. A literature survey was performed to identify characteristic morphological and physiological parameters. Realistic models were prepared and Monte Carlo simulations were performed to obtain hyperspectral images. Based on the simulations optimal wavelength regions for differentiation between normal and cholesterol rich skin were identified. Minimum Noise Fraction transformation (MNF) was used for analysis. In the second part of the study, the simulations were verified by a clinical study involving volunteers with elevated and normal levels of cholesterol. The faces of the volunteers were scanned by a hyperspectral camera covering the spectral range between 400 nm and 720 nm, and characteristic spectral features of the affected skin were identified. Processing of the images was done after conversion to reflectance and masking of the images. The identified features were compared to the known cholesterol levels of the subjects. The results of this study demonstrate that hyperspectral imaging of facial skin can be a promising, rapid modality for detection of hypercholesterolemia.

  14. New developments in two-photon analysis of human skin in vivo

    NASA Astrophysics Data System (ADS)

    Riemann, I.; Schwarz, M.; Stracke, F.; Ehlers, A.; Dimitrow, E.; Kaatz, M.; König, K.; Le Harzic, R.

    2009-02-01

    Two-photon imaging of human skin using ultra short laser pulses can be used to obtain information about the state of cells and tissues by means of their natural autofluorescence. Using this method, it is possible to determine whether the normal cell pattern is disturbed or the autofluorescence is influenced by internal or external stimuli. Two-photon fluorescence lifetime imaging (FLIM) can further enhance this providing information about physiological processes, fluorophores (like NAD(P)H, collagen, keratin, elastin, flavins, melanin,...) and external applied probes inside cells and tissue parts. For example the part of the cells metabolism and energy level can be determined by analyzing the NADH regarding its free / bound state and its oxidized / reduced state. The combination of two-photon imaging with FLIM may lead to a better understanding and diagnosis of skin reactions and disorders. We also present some results of in vivo simultaneous collagen and elastin measurements in skin dermis. Changes of dermal collagen and elastin content are characteristic for skin aging as well as for pathological skin conditions.

  15. Assessment of endothelial and neurovascular function in human skin microcirculation.

    PubMed

    Roustit, Matthieu; Cracowski, Jean-Luc

    2013-07-01

    Peripheral microvascular dysfunction has been described in many physiological and pathological conditions. Owing to its accessibility, the cutaneous microcirculation provides a unique index of microvascular function. Skin microvascular function has therefore been proposed as a prognostic marker or for evaluating the effect of drugs on the microcirculation. Various reactivity tests, coupled with techniques measuring skin blood flux, are used to non-invasively explore both endothelial and neurovascular microvascular functioning in humans. We review the advantages and limitations of the main reactivity tests, including post-occlusive reactive hyperemia, local thermal hyperemia, pressure-induced vasodilation, and iontophoresis of vasodilators, combined with measurement techniques such as laser Doppler and laser speckle contrast imaging. Recent advances in our comprehension of the physiological pathways underlying these reactivity tests, as well as technological developments in microcirculation imaging, have provided reliable and reproducible tools for studying the microcirculation.

  16. Role of topical peptides in preventing or treating aged skin.

    PubMed

    Gorouhi, F; Maibach, H I

    2009-10-01

    Ageing, a basic biological process seen in all living creatures, is not preventable. Surgical and topical modalities have been invented and substances were applied topically to alter the ageing process. Peptides and proteins, frequently used for this purpose, were categorized into four groups: signal peptides, enzyme-inhibitor peptides, neurotransmitter-inhibitor peptides and carrier peptides. We comprehensively review eligible studies -including controlled ex vivo or in vivo efficacy studies on any topical peptide or protein that has been administered to treat signs and symptoms of ageing.

  17. Differential expression of cathepsins K, S and V between young and aged Caucasian women skin epidermis.

    PubMed

    Sage, Juliette; De Quéral, Delphine; Leblanc-Noblesse, Emmanuelle; Kurfurst, Robin; Schnebert, Sylvianne; Perrier, Eric; Nizard, Carine; Lalmanach, Gilles; Lecaille, Fabien

    2014-01-01

    Cutaneous aging translates drastic structural and functional alterations in the extracellular matrix (ECM). Multiple mechanisms are involved, including changes in protease levels. We investigated the age-related protein expression and activity of cysteine cathepsins and the expression of two endogenous protein inhibitors in young and aged Caucasian women skin epidermis. Immunofluorescence studies indicate that the expression of cathepsins K, S and V, as well as cystatins A and M/E within keratinocytes is reduced in photoprotected skin of aged women. Furthermore, the overall endopeptidase activity of cysteine cathepsins in epidermis lysates decreased with age. Albeit dermal elastic fiber and laminin expression is reduced in aged skin, staining of nidogen-1, a key protein in BM assembly that is sensitive to proteolysis by cysteine, metallo- and serine proteases, has a similar pattern in both young and aged skin. Since cathepsins contribute to the hydrolysis and turnover of ECM/basement membrane components, the abnormal protein degradation and deposition during aging process may be related in part to a decline of lysosomal/endosomal cathepsin K, S and V activity.

  18. Optical Coherence Tomography Imaging of Normal, Chronologically Aged, Photoaged and Photodamaged Skin: A Systematic Review

    PubMed Central

    Mamalis, Andrew; Ho, Derek; Jagdeo, Jared

    2016-01-01

    BACKGROUND Optical coherence tomography (OCT) is capable of providing a non-invasive real-time cross-sectional image of the skin through the use of light-based interferometry– a method sometimes described as a “light-based ultrasound.” One key application of OCT in dermatology is the visualization of dermal collagen during processes such as chronological aging, photoaging, or photodamage. These skin conditions are typically managed by the practitioner’s subjective assessment of severity and response to therapy. METHODS & MATERIALS We searched Medline, PubMed, EMBASE, Web of Science, Google Scholar, and Cochrane databases for published literature on the imaging of skin collagen by OCT using the following search terms: “optical coherence tomography,” “OCT,” “skin,” “collagen,” “photoaging,” “wrinkles,” and “photodamage.” RESULTS Our search resulted in 23 articles investigating OCT skin collagen imaging meeting our search criteria. CONCLUSION We anticipate tremendous growth in the field of OCT skin imaging that will parallel the development ultrasound technology has experienced over the past 30 years. We foresee that OCT imaging to evaluate skin aging will not only help identify pathological changes earlier, but will also assist evaluation of response-to-therapy longitudinally without biopsy. PMID:26322560

  19. Biology of Zika Virus Infection in Human Skin Cells

    PubMed Central

    Hamel, Rodolphe; Dejarnac, Ophélie; Wichit, Sineewanlaya; Ekchariyawat, Peeraya; Neyret, Aymeric; Luplertlop, Natthanej; Perera-Lecoin, Manuel; Surasombatpattana, Pornapat; Talignani, Loïc; Thomas, Frédéric; Cao-Lormeau, Van-Mai; Choumet, Valérie; Briant, Laurence; Desprès, Philippe; Amara, Ali; Yssel, Hans

    2015-01-01

    ABSTRACT Zika virus (ZIKV) is an emerging arbovirus of the Flaviviridae family, which includes dengue, West Nile, yellow fever, and Japanese encephalitis viruses, that causes a mosquito-borne disease transmitted by the Aedes genus, with recent outbreaks in the South Pacific. Here we examine the importance of human skin in the entry of ZIKV and its contribution to the induction of antiviral immune responses. We show that human dermal fibroblasts, epidermal keratinocytes, and immature dendritic cells are permissive to the most recent ZIKV isolate, responsible for the epidemic in French Polynesia. Several entry and/or adhesion factors, including DC-SIGN, AXL, Tyro3, and, to a lesser extent, TIM-1, permitted ZIKV entry, with a major role for the TAM receptor AXL. The ZIKV permissiveness of human skin fibroblasts was confirmed by the use of a neutralizing antibody and specific RNA silencing. ZIKV induced the transcription of Toll-like receptor 3 (TLR3), RIG-I, and MDA5, as well as several interferon-stimulated genes, including OAS2, ISG15, and MX1, characterized by strongly enhanced beta interferon gene expression. ZIKV was found to be sensitive to the antiviral effects of both type I and type II interferons. Finally, infection of skin fibroblasts resulted in the formation of autophagosomes, whose presence was associated with enhanced viral replication, as shown by the use of Torin 1, a chemical inducer of autophagy, and the specific autophagy inhibitor 3-methyladenine. The results presented herein permit us to gain further insight into the biology of ZIKV and to devise strategies aiming to interfere with the pathology caused by this emerging flavivirus. IMPORTANCE Zika virus (ZIKV) is an arbovirus belonging to the Flaviviridae family. Vector-mediated transmission of ZIKV is initiated when a blood-feeding female Aedes mosquito injects the virus into the skin of its mammalian host, followed by infection of permissive cells via specific receptors. Indeed, skin immune

  20. Endurance training enhances vasodilation induced by nitric oxide in human skin.

    PubMed

    Boegli, Yann; Gremion, Gerald; Golay, Sandrine; Kubli, Sandrine; Liaudet, Lucas; Leyvraz, Pierre-François; Waeber, Bernard; Feihl, François

    2003-11-01

    Endurance training modifies the thermoregulatory control of skin blood flow, as manifested by a greater augmentation of skin perfusion for the same increase in core temperature in athletes, in comparison with sedentary subjects. In this study, we tested the hypothesis that a component of this adaptation might reside in a higher ability of cutaneous blood vessels to respond to vasodilatory stimuli. We recruited healthy nonsmoking males, either endurance trained or sedentary, in two different age ranges (18-35 y and >50 y). Skin blood flow was measured in the forearm skin, using a laser Doppler imager, allowing to record the vasodilatory responses to the following stimuli: iontophoresis of acetylcholine (an endothelium-dependent vasodilator), iontophoresis of sodium nitroprusside (a nitric oxide donor), and release of a temporary interruption of arterial inflow (reactive hyperemia). There was no effect of training on reactive hyperemia or the response to acetylcholine. In contrast, the increase in perfusion following the iontophoresis of sodium nitroprusside, expressed in perfusion units, was larger in trained than in sedentary subjects (younger: 398 +/- 54 vs 350 +/- 87, p < 0.05; older 339 +/- 72 vs 307 +/- 66, p < 0.05). In conclusion, endurance training enhances the vasodilatory effects of nitric oxide in the human dermal microcirculation, at least in forearm skin. These observations have considerable physiologic interest in view of recent data indicating that nitric oxide mediates in part the cutaneous vasodilation induced by heat stress in humans. Therefore, the augmentation of nitric oxide bioactivity in the dermal microcirculation might be one mechanism whereby endurance training modifies the thermoregulatory control of skin blood flow.

  1. Age, Health and Attractiveness Perception of Virtual (Rendered) Human Hair

    PubMed Central

    Fink, Bernhard; Hufschmidt, Carla; Hirn, Thomas; Will, Susanne; McKelvey, Graham; Lankhof, John

    2016-01-01

    The social significance of physical appearance and beauty has been documented in many studies. It is known that even subtle manipulations of facial morphology and skin condition can alter people’s perception of a person’s age, health and attractiveness. While the variation in facial morphology and skin condition cues has been studied quite extensively, comparably little is known on the effect of hair on social perception. This has been partly caused by the technical difficulty of creating appropriate stimuli for investigations of people’s response to systematic variation of certain hair characteristics, such as color and style, while keeping other features constant. Here, we present a modeling approach to the investigation of human hair perception using computer-generated, virtual (rendered) human hair. In three experiments, we manipulated hair diameter (Experiment 1), hair density (Experiment 2), and hair style (Experiment 3) of human (female) head hair and studied perceptions of age, health and attractiveness. Our results show that even subtle changes in these features have an impact on hair perception. We discuss our findings with reference to previous studies on condition-dependent quality cues in women that influence human social perception, thereby suggesting that hair is a salient feature of human physical appearance, which contributes to the perception of beauty. PMID:28066276

  2. Age, Health and Attractiveness Perception of Virtual (Rendered) Human Hair.

    PubMed

    Fink, Bernhard; Hufschmidt, Carla; Hirn, Thomas; Will, Susanne; McKelvey, Graham; Lankhof, John

    2016-01-01

    The social significance of physical appearance and beauty has been documented in many studies. It is known that even subtle manipulations of facial morphology and skin condition can alter people's perception of a person's age, health and attractiveness. While the variation in facial morphology and skin condition cues has been studied quite extensively, comparably little is known on the effect of hair on social perception. This has been partly caused by the technical difficulty of creating appropriate stimuli for investigations of people's response to systematic variation of certain hair characteristics, such as color and style, while keeping other features constant. Here, we present a modeling approach to the investigation of human hair perception using computer-generated, virtual (rendered) human hair. In three experiments, we manipulated hair diameter (Experiment 1), hair density (Experiment 2), and hair style (Experiment 3) of human (female) head hair and studied perceptions of age, health and attractiveness. Our results show that even subtle changes in these features have an impact on hair perception. We discuss our findings with reference to previous studies on condition-dependent quality cues in women that influence human social perception, thereby suggesting that hair is a salient feature of human physical appearance, which contributes to the perception of beauty.

  3. Apigenin inhibits UVA-induced cytotoxicity in vitro and prevents signs of skin aging in vivo.

    PubMed

    Choi, Sungjin; Youn, Jeungyeun; Kim, Karam; Joo, Da Hye; Shin, Shanghun; Lee, Jeongju; Lee, Hyun Kyung; An, In-Sook; Kwon, Seungbin; Youn, Hae Jeong; Ahn, Kyu Joong; An, Sungkwan; Cha, Hwa Jun

    2016-08-01

    Apigenin (4',5,7-trihydroxyflavone) is a flavone that has been reported to have anti-inflammatory, antioxidant and anti-carcinogenic properties. In this study, we investigated the protective effects of apigenin on skin and found that, in experiments using cells, apigenin restored the viability of normal human dermal fibroblasts (nHDFs), which had been decreased by exposure to ultraviolet (UV) radiation in the UVA range. Using a senescence-associated (SA)-β-gal assay, we also demonstrate that apigenin protects against the UVA-induced senescence of nHDFs. Furthermore, we found that apigenin decreased the expression of the collagenase, matrix metalloproteinase (MMP)-1, in UVA-irradiated nHDFs. UVA, which has been previously identified as a photoaging-inducing factor, has been shown to induce MMP-1 expression. The elevated expression of MMP-1 impairs the collagen matrix, leading to the loss of elasticity and skin dryness. Therefore, we examined the clinical efficacy of apigenin on aged skin, using an apigenin‑containing cream for clinical application. Specifically, we measured dermal density, skin elasticity and the length of fine wrinkles in subjects treated with apigenin cream or the control cream without apigenin. Additionally, we investigated the effects of the apigenin-containing cream on skin texture, moisture and transepidermal water loss (TEWL). From these experiments, we found that the apigenin‑containing cream increased dermal density and elasticity, and reduced fine wrinkle length. It also improved skin evenness, moisture content and TEWL. These results clearly demonstrate the biological effects of apigenin, demonstrating both its cellular and clinical efficacy, and suggest that this compound holds promise as an anti-aging cosmetic ingredient.

  4. Simulation of fluorescent measurements in the human skin

    NASA Astrophysics Data System (ADS)

    Meglinski, Igor V.; Sinichkin, Yurii P.; Utz, Sergei R.; Pilipenko, Helena A.

    1995-05-01

    Reflectance and fluorescence spectroscopy are successfully used for skin disease diagnostics. Human skin optical parameters are defined by its turbid, scattering properties with nonuniform absorption and fluorescence chromophores distribution, its multilayered structure, and variability under different physiological and pathological conditions. Theoretical modeling of light propagation in skin could improve the understanding of these condition and may be useful in the interpretation of in vivo reflectance and autofluorescence (AF) spectra. Laser application in medical optical tomography, tissue spectroscopy, and phototherapy stimulates the development of optical and mathematical light-tissue interaction models allowing to account the specific features of laser beam and tissue inhomogeneities. This paper presents the version of a Monte Carlo method for simulating of optical radiation propagation in biotissue and highly scattering media, allowing for 3D geometry of a medium. The simulation is based on use of Green's function of medium response to single external pulse. The process of radiation propagation is studied in the area with given boundary conditions, taking into account the processes of reflection and refraction at the boundaries of layers inside the medium under study. Results of Monte Carlo simulation were compared with experimental investigations and demonstrated good agreement.

  5. Recovery of latent fingerprints and DNA on human skin.

    PubMed

    Färber, Doris; Seul, Andrea; Weisser, Hans-Joachim; Bohnert, Michael

    2010-11-01

    The project "Latent Fingerprints and DNA on Human Skin" was the first systematic research in Europe dealing with detection of fingerprints and DNA left by offenders on the skin of corpses. One thousand samples gave results that allow general statements on the materials and methods used. The tests were carried out according to a uniform trial structure. Fingerprints were deposited by natural donors on corpses. The latent fingerprints were treated with magnetic powder or black fingerprint powder. Afterward, they were lifted with silicone casting material (Isomark(®)) or gelatine foil. All lifts were swabbed to recover DNA. It was possible to visualize comparable and identifiable fingerprints on the skin of corpses (16%). In the same categories, magnetic powder (18.4%) yielded better results than black fingerprint powder (13.6%). The number of comparable and identifiable fingerprints decreased on the lifts (12.7%). Isomark(®) (14.9%) was the better lifting material in comparison with gelatine foil (10.1%). In one-third of the samples, DNA could be extracted from the powdered and lifted latents. Black fingerprint powder delivered the better result with a rate of 2.2% for full DNA profiles and profiles useful for exclusion in comparison with 1.8% for the magnetic powder traces. Isomark(®) (3.1%) yielded better results than gelatine foil (0.6%).

  6. In vivo optical coherence tomography of human skin microstructure

    NASA Astrophysics Data System (ADS)

    Sergeev, Alexander M.; Gelikonov, Valentin M.; Gelikonov, Grigory V.; Feldchtein, Felix I.; Pravdenko, Kirill I.; Shabanov, Dmitry V.; Gladkova, Natalia D.; Pochinko, Vitaly; Zhegalov, V.; Dmitriev, G.; Vazina, I.; Petrova, Galina P.; Nikulin, Nikolai K.

    1994-12-01

    A compact effective optical coherence tomography (OCT) system is presented. It contains approximately equals 0.3 mW superluminescent diode with spectral width 30 nm FWHM (providing approximately equals 15 micrometers longitudinal resolution) and fiber interferometer with integrated longitudinal scanning. The dynamic range 60 dB allows to observe structure of human skin in vivo up to 1.5 mm in depth. A comparison of obtained tomographs with data of histologic analysis of the same samples of the skin have been carried out to identify the observed structures and determine their optical properties. This technique allows one to perform noncontact, noninvasive diagnostic of early stages of different pathological state of the skin, to measure the burn depth and to observe the process of the recovery. Unlike scanning confocal microscopy, OCT is more suitable for an endoscopic investigation of the mucous membranes of hollow organs. Possible diagnostic applications include dermatology, gastroenterology, gynecology, urology, oncology, othorinolaryngology, transplantology. The most promising features are the potential possibility of differential diagnosis of precancer and various types of cancer, estimation of the invasion depth, differential diagnosis of inflammation and dystrophic processes, control of radical operative treatment.

  7. Correlation between experimental human and murine skin sensitization induction thresholds.

    PubMed

    Api, Anne Marie; Basketter, David; Lalko, Jon

    2015-01-01

    Quantitative risk assessment for skin sensitization is directed towards the determination of levels of exposure to known sensitizing substances that will avoid the induction of contact allergy in humans. A key component of this work is the predictive identification of relative skin sensitizing potency, achieved normally by the measurement of the threshold (the "EC3" value) in the local lymph node assay (LLNA). In an extended series of studies, the accuracy of this murine induction threshold as the predictor of the absence of a sensitizing effect has been verified by conduct of a human repeated insult patch test (HRIPT). Murine and human thresholds for a diverse set of 57 fragrance chemicals spanning approximately four orders of magnitude variation in potency have been compared. The results confirm that there is a useful correlation, with the LLNA EC3 value helping particularly to identify stronger sensitizers. Good correlation (with half an order of magnitude) was seen with three-quarters of the dataset. The analysis also helps to identify potential outlier types of (fragrance) chemistry, exemplified by hexyl and benzyl salicylates (an over-prediction) and trans-2-hexenal (an under-prediction).

  8. Localization of the defect in skin diseases analyzed in the human skin graft-nude mouse model.

    PubMed

    Briggaman, R A

    1980-01-01

    Human skin can be grown away from its donor for prolonged periods as grafts on congenitally athymic "nude" mice. This system has been used to analyze the defect in several skin diseases, specifically to localize the site of the defect to the skin itself or to the epidermal or dermal components of the skin. In order to validate the use of the nude mouse human skin graft system in the analysis of skin defects, we have demonstrated that a systemic metabolic defect which involves the skin, namely essential fatty acid deficiency, can be differentiated from a defect residing primarily in the skin itself. Skin-marker systems have been developed for use with the nude mouse-human skin graft model to document the identity of human skin grafts and epidermal and dermal components of the grafts after prolonged periods of growth on the nude athymic mice. Y-body, a small fluorescent segment of the Y-chromosome seen in interphase cells, is used as a sex marker and serves to distinguish sex differences between the graft and the mouse recipient or between skin components of the graft. The ABH "blood-group" antigens are present on differentiated epidermal cell surfaces and identify the grafted epidermis according to the blood groups of the donor. In previous studies, lamellar ichthyosis was shown to be well maintained after prolonged periods of growth on nude athymic mice, indicating that the defect in this disease resides in the skin itself. Recombinant grafts composed of normal and lamellar ichthyosis epidermis and dermis further localize the defect to lamellar ichthyosis epidermis. Psoriasis is well maintained on the nude mouse-skin graft model. The epidermal hyperplasia and hyperproliferative epidermal cell kinetics of psoriasis are manifested in the grafts of active psoriasis maintained for prolonged periods on the nude mice, but the inflammatory component of psoriasis is absent. Recombinant graft studies utilizing normal and psoriatic epidermis and dermis demonstrate psoriasis

  9. Pyrimidine dimer formation and repair in human skin

    SciTech Connect

    Sutherland, B.M.; Harber, L.C.; Kochevar, I.E.

    1980-09-01

    Cyclobutyl pyrimidine dimers have been detected in the DNA of human skin following in vivo irradiation with suberythermal doses of ultraviolet (UV) radiation from FS-20 sun lamp fluorescent tubes. Dimers were assayed by treatment of extracted DNA with Micrococus luteus UV-specific endonuclease, alkaline agarose electrophoresis, and ethidum bromide staining. This technique, in contrast to conventional dimer assays, can be used with nonradioactive DNA and is optimal at low UV light doses. These data suggest that some dimer disappearance by excision repair occurs within 20 min of UV irradiation and that photoreactivation of dimers can make a contribution to the total repair process.

  10. Investigation of the Efficacy of Transdermal Penetration Enhancers Through the Use of Human Skin and a Skin Mimic Artificial Membrane.

    PubMed

    Balázs, Boglárka; Vizserálek, Gábor; Berkó, Szilvia; Budai-Szűcs, Mária; Kelemen, András; Sinkó, Bálint; Takács-Novák, Krisztina; Szabó-Révész, Piroska; Csányi, Erzsébet

    2016-03-01

    The aim of this study was to investigate the behavior of promising penetration enhancers through the use of 2 different skin test systems. Hydrogel-based transdermal formulations were developed with ibuprofen as a nonsteroidal anti-inflammatory drug. Transcutol and sucrose esters were used as biocompatible penetration enhancers. The permeability measurements were performed with ex vivo Franz diffusion cell methods and a newly developed Skin Parallel Artificial Membrane Permeability Assays (PAMPA) model. Franz diffusion measurement is commonly used as a research tool in studies of diffusion through synthetic membranes in vitro or penetration through ex vivo human skin, whereas Skin PAMPA involves recently published artificial membrane-based technology for the fast prediction of skin penetration. It is a 96-well plate-based model with optimized artificial membrane structure containing free fatty acid, cholesterol, and synthetic ceramide analog compounds to mimic the stratum corneum barrier function. Transdermal preparations containing 2.64% of different sucrose esters and/or Transcutol and a constant (5%) of ibuprofen were investigated to determine the effects of these penetration enhancers. The study demonstrated the good correlation of the permeability data obtained through use of human skin membrane and the in vitro Skin PAMPA system. The Skin PAMPA artificial membrane serves as quick and relatively deep tool in the early stages of transdermal delivery systems, through which the enhancing efficacy of excipients can be screened so as to facilitate the choice of effective penetration components.

  11. In vitro dermal absorption of pyrethroid pesticides in human and rat skin.

    PubMed

    Hughes, Michael F; Edwards, Brenda C

    2010-07-01

    Dermal exposure to pyrethroid pesticides can occur during manufacture and application. This study examined the in vitro dermal absorption of pyrethroids using rat and human skin. Dermatomed skin from adult male Long Evans rats or human cadavers was mounted in flow-through diffusion cells, and radiolabeled bifenthrin, deltamethrin or cis-permethrin was applied in acetone to the skin. Fractions of receptor fluid were collected every 4h. At 24h, the skins were washed with soap and water to remove unabsorbed chemical. The skin was then solubilized. Two additional experiments were performed after washing the skin; the first was tape-stripping the skin and the second was the collection of receptor fluid for an additional 24 h. Receptor fluid, skin washes, tape strips and skin were analyzed for radioactivity. For rat skin, the wash removed 53-71% of the dose and 26-43% remained in the skin. The cumulative percentage of the dose at 24 h in the receptor fluid ranged from 1 to 5%. For human skin, the wash removed 71-83% of the dose and 14-25% remained in the skin. The cumulative percentage of the dose at 24 h in the receptor fluid was 1-2%. Tape-stripping removed 50-56% and 79-95% of the dose in rat and human skin, respectively, after the wash. From 24-48 h, 1-3% and about 1% of the dose diffused into the receptor fluid of rat and human skin, respectively. The pyrethroids bifenthrin, deltamethrin and cis-permethrin penetrated rat and human skin following dermal application in vitro. However, a skin wash removed 50% or more of the dose from rat and human skin. Rat skin was more permeable to the pyrethroids than human skin. Of the dose in skin, 50% or more was removed by tape-stripping, suggesting that permeation of pyrethroids into viable tissue could be impeded. The percentage of the dose absorbed into the receptor fluid was considerably less than the dose in rat and human skin. Therefore, consideration of the skin type used and fractions analyzed are important when using in

  12. In vitro dermal absorption of pyrethroid pesticides in human and rat skin

    SciTech Connect

    Hughes, Michael F.; Edwards, Brenda C.

    2010-07-15

    Dermal exposure to pyrethroid pesticides can occur during manufacture and application. This study examined the in vitro dermal absorption of pyrethroids using rat and human skin. Dermatomed skin from adult male Long Evans rats or human cadavers was mounted in flow-through diffusion cells, and radiolabeled bifenthrin, deltamethrin or cis-permethrin was applied in acetone to the skin. Fractions of receptor fluid were collected every 4 h. At 24 h, the skins were washed with soap and water to remove unabsorbed chemical. The skin was then solubilized. Two additional experiments were performed after washing the skin; the first was tape-stripping the skin and the second was the collection of receptor fluid for an additional 24 h. Receptor fluid, skin washes, tape strips and skin were analyzed for radioactivity. For rat skin, the wash removed 53-71% of the dose and 26-43% remained in the skin. The cumulative percentage of the dose at 24 h in the receptor fluid ranged from 1 to 5%. For human skin, the wash removed 71-83% of the dose and 14-25% remained in the skin. The cumulative percentage of the dose at 24 h in the receptor fluid was 1-2%. Tape-stripping removed 50-56% and 79-95% of the dose in rat and human skin, respectively, after the wash. From 24-48 h, 1-3% and about 1% of the dose diffused into the receptor fluid of rat and human skin, respectively. The pyrethroids bifenthrin, deltamethrin and cis-permethrin penetrated rat and human skin following dermal application in vitro. However, a skin wash removed 50% or more of the dose from rat and human skin. Rat skin was more permeable to the pyrethroids than human skin. Of the dose in skin, 50% or more was removed by tape-stripping, suggesting that permeation of pyrethroids into viable tissue could be impeded. The percentage of the dose absorbed into the receptor fluid was considerably less than the dose in rat and human skin. Therefore, consideration of the skin type used and fractions analyzed are important when using

  13. Steroid synthesis by primary human keratinocytes; implications for skin disease

    SciTech Connect

    Hannen, Rosalind F.; Michael, Anthony E.; Jaulim, Adil; Bhogal, Ranjit; Burrin, Jacky M.; Philpott, Michael P.

    2011-01-07

    Research highlights: {yields} Primary keratinocytes express the steroid enzymes required for cortisol synthesis. {yields} Normal primary human keratinocytes can synthesise cortisol. {yields} Steroidogenic regulators, StAR and MLN64, are expressed in normal epidermis. {yields} StAR expression is down regulated in eczema and psoriatic epidermis. -- Abstract: Cortisol-based therapy is one of the most potent anti-inflammatory treatments available for skin conditions including psoriasis and atopic dermatitis. Previous studies have investigated the steroidogenic capabilities of keratinocytes, though none have demonstrated that these skin cells, which form up to 90% of the epidermis are able to synthesise cortisol. Here we demonstrate that primary human keratinocytes (PHK) express all the elements required for cortisol steroidogenesis and metabolise pregnenolone through each intermediate steroid to cortisol. We show that normal epidermis and cultured PHK express each of the enzymes (CYP11A1, CYP17A1, 3{beta}HSD1, CYP21 and CYP11B1) that are required for cortisol synthesis. These enzymes were shown to be metabolically active for cortisol synthesis since radiometric conversion assays traced the metabolism of [7-{sup 3}H]-pregnenolone through each steroid intermediate to [7-{sup 3}H]-cortisol in cultured PHK. Trilostane (a 3{beta}HSD1 inhibitor) and ketoconazole (a CYP17A1 inhibitor) blocked the metabolism of both pregnenolone and progesterone. Finally, we show that normal skin expresses two cholesterol transporters, steroidogenic acute regulatory protein (StAR), regarded as the rate-determining protein for steroid synthesis, and metastatic lymph node 64 (MLN64) whose function has been linked to cholesterol transport in steroidogenesis. The expression of StAR and MLN64 was aberrant in two skin disorders, psoriasis and atopic dermatitis, that are commonly treated with cortisol, suggesting dysregulation of epidermal steroid synthesis in these patients. Collectively these data

  14. Detection of hypercholesterolemia using hyperspectral imaging of human skin

    NASA Astrophysics Data System (ADS)

    Milanic, Matija; Bjorgan, Asgeir; Larsson, Marcus; Strömberg, Tomas; Randeberg, Lise L.

    2015-07-01

    Hypercholesterolemia is characterized by high blood levels of cholesterol and is associated with increased risk of atherosclerosis and cardiovascular disease. Xanthelasma is a subcutaneous lesion appearing in the skin around the eyes. Xanthelasma is related to hypercholesterolemia. Identifying micro-xanthelasma can thereforeprovide a mean for early detection of hypercholesterolemia and prevent onset and progress of disease. The goal of this study was to investigate spectral and spatial characteristics of hypercholesterolemia in facial skin. Optical techniques like hyperspectral imaging (HSI) might be a suitable tool for such characterization as it simultaneously provides high resolution spatial and spectral information. In this study a 3D Monte Carlo model of lipid inclusions in human skin was developed to create hyperspectral images in the spectral range 400-1090 nm. Four lesions with diameters 0.12-1.0 mm were simulated for three different skin types. The simulations were analyzed using three algorithms: the Tissue Indices (TI), the two layer Diffusion Approximation (DA), and the Minimum Noise Fraction transform (MNF). The simulated lesions were detected by all methods, but the best performance was obtained by the MNF algorithm. The results were verified using data from 11 volunteers with known cholesterol levels. The face of the volunteers was imaged by a LCTF system (400- 720 nm), and the images were analyzed using the previously mentioned algorithms. The identified features were then compared to the known cholesterol levels of the subjects. Significant correlation was obtained for the MNF algorithm only. This study demonstrates that HSI can be a promising, rapid modality for detection of hypercholesterolemia.

  15. Human skin pigmentation as an adaptation to UV radiation

    PubMed Central

    Jablonski, Nina G.; Chaplin, George

    2010-01-01

    Human skin pigmentation is the product of two clines produced by natural selection to adjust levels of constitutive pigmentation to levels of UV radiation (UVR). One cline was generated by high UVR near the equator and led to the evolution of dark, photoprotective, eumelanin-rich pigmentation. The other was produced by the requirement for UVB photons to sustain cutaneous photosynthesis of vitamin D3 in low-UVB environments, and resulted in the evolution of depigmented skin. As hominins dispersed outside of the tropics, they experienced different intensities and seasonal mixtures of UVA and UVB. Extreme UVA throughout the year and two equinoctial peaks of UVB prevail within the tropics. Under these conditions, the primary selective pressure was to protect folate by maintaining dark pigmentation. Photolysis of folate and its main serum form of 5-methylhydrofolate is caused by UVR and by reactive oxygen species generated by UVA. Competition for folate between the needs for cell division, DNA repair, and melanogenesis is severe under stressful, high-UVR conditions and is exacerbated by dietary insufficiency. Outside of tropical latitudes, UVB levels are generally low and peak only once during the year. The populations exhibiting maximally depigmented skin are those inhabiting environments with the lowest annual and summer peak levels of UVB. Development of facultative pigmentation (tanning) was important to populations settling between roughly 23° and 46° , where levels of UVB varied strongly according to season. Depigmented and tannable skin evolved numerous times in hominin evolution via independent genetic pathways under positive selection. PMID:20445093

  16. The circadian clock in skin: implications for adult stem cells, tissue regeneration, cancer, aging, and immunity

    PubMed Central

    Plikus, Maksim V.; Van Spyk, Elyse Noelani; Pham, Kim; Geyfman, Mikhail; Kumar, Vivek; Takahashi, Joseph S.; Andersen, Bogi

    2015-01-01

    Historically work on peripheral circadian clocks has been focused on organs and tissues that have prominent metabolic functions, such as liver, fat and muscle. In recent years, skin is emerging as a model for studying circadian clock regulation of cell proliferation, stem cell functions, tissue regeneration, aging and carcinogenesis. Morphologically skin is complex, containing multiple cell types and structures, and there is evidence for a functional circadian clock in most, if not all, of its cell types. Despite the complexity, skin stem cell populations are well defined, experimentally tractable and exhibit prominent daily cell proliferation cycles. Hair follicle stem cells also participate in recurrent, long-lasting cycles of regeneration -- the hair growth cycles. Among other advantages of skin is a broad repertoire of available genetic tools enabling the creation of cell-type specific circadian mutants. Also, due to the accessibility of the skin, in vivo imaging techniques can be readily applied to study the circadian clock and its outputs in real time, even at the single-cell level. Skin provides the first line of defense against many environmental and stress factors that exhibit dramatic diurnal variations such as solar UV radiation and temperature. Studies have already linked the circadian clock to the control of UVB-induced DNA damage and skin cancers. Due to the important role that skin plays in the defense against microorganisms, it represents a promising model system to further explore the role of the clock in the regulation of the body's immune functions. To that end, recent studies have already linked the circadian clock to psoriasis, one of the most common immune-mediated skin disorders. The skin also provides opportunities to interrogate clock regulation of tissue metabolism in the context of stem cells and regeneration. Furthermore, many animal species feature prominent seasonal hair molt cycles, offering an attractive model for investigating the

  17. The circadian clock in skin: implications for adult stem cells, tissue regeneration, cancer, aging, and immunity.

    PubMed

    Plikus, Maksim V; Van Spyk, Elyse N; Pham, Kim; Geyfman, Mikhail; Kumar, Vivek; Takahashi, Joseph S; Andersen, Bogi

    2015-06-01

    Historically, work on peripheral circadian clocks has been focused on organs and tissues that have prominent metabolic functions, such as the liver, fat, and muscle. In recent years, skin has emerged as a model for studying circadian clock regulation of cell proliferation, stem cell functions, tissue regeneration, aging, and carcinogenesis. Morphologically, skin is complex, containing multiple cell types and structures, and there is evidence for a functional circadian clock in most, if not all, of its cell types. Despite the complexity, skin stem cell populations are well defined, experimentally tractable, and exhibit prominent daily cell proliferation cycles. Hair follicle stem cells also participate in recurrent, long-lasting cycles of regeneration: the hair growth cycles. Among other advantages of skin is a broad repertoire of available genetic tools enabling the creation of cell type-specific circadian mutants. Also, due to the accessibility of skin, in vivo imaging techniques can be readily applied to study the circadian clock and its outputs in real time, even at the single-cell level. Skin provides the first line of defense against many environmental and stress factors that exhibit dramatic diurnal variations such as solar ultraviolet (UV) radiation and temperature. Studies have already linked the circadian clock to the control of UVB-induced DNA damage and skin cancers. Due to the important role that skin plays in the defense against microorganisms, it also represents a promising model system to further explore the role of the clock in the regulation of the body's immune functions. To that end, recent studies have already linked the circadian clock to psoriasis, one of the most common immune-mediated skin disorders. Skin also provides opportunities to interrogate the clock regulation of tissue metabolism in the context of stem cells and regeneration. Furthermore, many animal species feature prominent seasonal hair molt cycles, offering an attractive model

  18. In vitro biocompatibility of chitosan porous skin regenerating templates (PSRTs) using primary human skin keratinocytes.

    PubMed

    Lim, C K; Yaacob, N S; Ismail, Z; Halim, A S

    2010-04-01

    Biopolymer chitosan (beta-1,4-d-glucosamine) comprises the copolymer mixture of N-acetylglucosamine and glucosamine. The natural biocompatibility and biodegradability of chitosan have recently highlighted its potential use for applications in wound management. Chemical and physical modifications of chitosan influence its biocompatibility and biodegradability, but it is unknown as to what degree. Hence, the biocompatibility of the chitosan porous skin regenerating templates (PSRT 82, 87 and 108) was determined using an in vitro toxicology model at the cellular and molecular level on primary normal human epidermal keratinocytes (pNHEK). Cytocompatibility was accessed by using a 3-[4,5-dimethyl-2-thiazolyl]-2,5-diphenyl tetrazolium bromide (MTT) assay from 24 to 72h. To assess the genotoxicity of the PSRTs, DNA damage to the pNHEK was evaluated by using the Comet assay following direct contact with the various PSRTs. Furthermore, the skin pro-inflammatory cytokines TNF-alpha and IL-8 were examined to evaluate the tendency of the PSRTs to provoke inflammatory responses. All PSRTs were found to be cytocompatible, but only PSRT 108 was capable of stimulating cell proliferation. While all of the PSRTs showed some DNA damage, PSRT 108 showed the least DNA damage followed by PSRT 87 and 82. PSRT 87 and 82 induced a higher secretion of TNF-alpha and IL-8 in the pNHEK cultures than did PSRT 108. Hence, based on our experiments, PSRT 108 is the most biocompatible wound dressing of the three tested.

  19. The Protective Role of Melanin Against UV Damage in Human Skin

    PubMed Central

    Brenner, Michaela; Hearing, Vincent J.

    2009-01-01

    Human skin is repeatedly exposed to ultraviolet radiation (UVR) that influences the function and survival of many cell types and is regarded as the main causative factor in the induction of skin cancer. It has been traditionally believed that skin pigmentation is the most important photoprotective factor, since melanin, besides functioning as a broadband UV absorbent, has antioxidant and radical scavenging properties. Besides, many epidemiological studies have shown a lower incidence for skin cancer in individuals with darker skin compared to those with fair skin. Skin pigmentation is of great cultural and cosmetic importance, yet the role of melanin in photoprotection is still controversial. This article outlines the major acute and chronic effects of UV radiation on human skin, the properties of melanin, the regulation of pigmentation and its effect on skin cancer prevention. PMID:18435612

  20. Multiple-reflection model of human skin and estimation of pigment concentrations

    NASA Astrophysics Data System (ADS)

    Ohtsuki, Rie; Tominaga, Shoji; Tanno, Osamu

    2012-07-01

    We describe a new method for estimating the concentrations of pigments in the human skin using surface spectral reflectance. We derive an equation that expresses the surface spectral reflectance of the human skin. First, we propose an optical model of the human skin that accounts for the stratum corneum. We also consider the difference between the scattering coefficient of the epidermis and that of the dermis. We then derive an equation by applying the Kubelka-Munk theory to an optical model of the human skin. Unlike a model developed in a recent study, the present equation considers pigments as well as multiple reflections and the thicknesses of the skin layers as factors that affect the color of the human skin. In two experiments, we estimate the pigment concentrations using the measured surface spectral reflectances. Finally, we confirm the feasibility of the concentrations estimated by the proposed method by evaluating the estimated pigment concentrations in the skin.

  1. Purification, characterization and inhibition of human skin collagenase

    PubMed Central

    Woolley, David E.; Glanville, Robert W.; Roberts, Dennis R.; Evanson, John M.

    1978-01-01

    1. The neutral collagenase released into the culture medium by explants of human skin tissue was purified by ultrafiltration and column chromatography. The final enzyme preparation had a specific activity against thermally reconstituted collagen fibrils of 32μg of collagen degraded/min per mg of enzyme protein, representing a 266-fold increase over that of the culture medium. Electrophoresis in polyacrylamide disc gels showed it to migrate as a single protein band from which enzyme activity could be eluted. Chromatographic and polyacrylamide-gel-elution experiments provided no evidence for the existence of more than one active collagenase. 2. The molecular weight of the enzyme estimated from gel filtration and sodium dodecyl sulphate/polyacrylamide-gel electrophoresis was approx. 60000. The purified collagenase, having a pH optimum of 7.5–8.5, did not hydrolyse the synthetic collagen peptide 4-phenylazobenzyloxycarbonyl-Pro-Leu-Gly-Pro-d-Arg-OH and had no non-specific proteinase activity when examined against non-collagenous proteins. 3. It attacked undenatured collagen in solution at 25°C, producing the two characteristic products TCA(¾) and TCB(¼). Collagen types I, II and III were all cleaved in a similar manner by the enzyme at 25°C, but under similar conditions basement-membrane collagen appeared not to be susceptible to collagenase attack. At 37°C the enzyme attacked gelatin, producing initially three-quarter and one-quarter fragments of the α-chains, which were degraded further at a lower rate. As judged by the release of soluble hydroxyproline peptides and electron microscopy, the purified enzyme degraded insoluble collagen derived from human skin at 37°C, but at a rate much lower than that for reconstituted collagen fibrils. 4. Inhibition of the skin collagenase was obtained with EDTA, 1,10-phenanthroline, cysteine, dithiothreitol and sodium aurothiomaleate. Cartilage proteoglycans did not inhibit the enzyme. The serum proteins α2-macroglobulin

  2. Assessment of penetration of quantum dots through in vitro and in vivo human skin using the human skin equivalent model and the tape stripping method

    SciTech Connect

    Jeong, Sang Hoon; Kim, Jae Hwan; Yi, Sang Min; Lee, Jung Pyo; Kim, Jin Ho; Sohn, Kyung Hee; Park, Kui Lea; Kim, Meyoung-Kon; Son, Sang Wook

    2010-04-09

    Quantum dots (QDs) are rapidly emerging as an important class of nanoparticles (NPs) with potential applications in medicine. However, little is known about penetration of QDs through human skin. This study investigated skin penetration of QDs in both in vivo and in vitro human skin. Using the tape stripping method, this study demonstrates for the first time that QDs can actually penetrate through the stratum corneum (SC) of human skin. Transmission electron microscope (TEM) and energy diverse X-ray (EDX) analysis showed accumulation of QDs in the SC of a human skin equivalent model (HSEM) after dermal exposure to QDs. These findings suggest possible transdermal absorption of QDs after dermal exposure over a relatively long period of time.

  3. The Impact of Environmental and Endogenous Damage on Somatic Mutation Load in Human Skin Fibroblasts

    PubMed Central

    Saini, Natalie; Chan, Kin; Grimm, Sara A.; Dai, Shuangshuang; Fargo, David C.; Kaufmann, William K.; Taylor, Jack A.; Lee, Eunjung; Cortes-Ciriano, Isidro; Park, Peter J.; Schurman, Shepherd H.; Malc, Ewa P.; Mieczkowski, Piotr A.

    2016-01-01

    Accumulation of somatic changes, due to environmental and endogenous lesions, in the human genome is associated with aging and cancer. Understanding the impacts of these processes on mutagenesis is fundamental to understanding the etiology, and improving the prognosis and prevention of cancers and other genetic diseases. Previous methods relying on either the generation of induced pluripotent stem cells, or sequencing of single-cell genomes were inherently error-prone and did not allow independent validation of the mutations. In the current study we eliminated these potential sources of error by high coverage genome sequencing of single-cell derived clonal fibroblast lineages, obtained after minimal propagation in culture, prepared from skin biopsies of two healthy adult humans. We report here accurate measurement of genome-wide magnitude and spectra of mutations accrued in skin fibroblasts of healthy adult humans. We found that every cell contains at least one chromosomal rearrangement and 600–13,000 base substitutions. The spectra and correlation of base substitutions with epigenomic features resemble many cancers. Moreover, because biopsies were taken from body parts differing by sun exposure, we can delineate the precise contributions of environmental and endogenous factors to the accrual of genetic changes within the same individual. We show here that UV-induced and endogenous DNA damage can have a comparable impact on the somatic mutation loads in skin fibroblasts. Trial Registration ClinicalTrials.gov NCT01087307 PMID:27788131

  4. The Impact of Environmental and Endogenous Damage on Somatic Mutation Load in Human Skin Fibroblasts.

    PubMed

    Saini, Natalie; Roberts, Steven A; Klimczak, Leszek J; Chan, Kin; Grimm, Sara A; Dai, Shuangshuang; Fargo, David C; Boyer, Jayne C; Kaufmann, William K; Taylor, Jack A; Lee, Eunjung; Cortes-Ciriano, Isidro; Park, Peter J; Schurman, Shepherd H; Malc, Ewa P; Mieczkowski, Piotr A; Gordenin, Dmitry A

    2016-10-01

    Accumulation of somatic changes, due to environmental and endogenous lesions, in the human genome is associated with aging and cancer. Understanding the impacts of these processes on mutagenesis is fundamental to understanding the etiology, and improving the prognosis and prevention of cancers and other genetic diseases. Previous methods relying on either the generation of induced pluripotent stem cells, or sequencing of single-cell genomes were inherently error-prone and did not allow independent validation of the mutations. In the current study we eliminated these potential sources of error by high coverage genome sequencing of single-cell derived clonal fibroblast lineages, obtained after minimal propagation in culture, prepared from skin biopsies of two healthy adult humans. We report here accurate measurement of genome-wide magnitude and spectra of mutations accrued in skin fibroblasts of healthy adult humans. We found that every cell contains at least one chromosomal rearrangement and 600–13,000 base substitutions. The spectra and correlation of base substitutions with epigenomic features resemble many cancers. Moreover, because biopsies were taken from body parts differing by sun exposure, we can delineate the precise contributions of environmental and endogenous factors to the accrual of genetic changes within the same individual. We show here that UV-induced and endogenous DNA damage can have a comparable impact on the somatic mutation loads in skin fibroblasts. Trial Registration: ClinicalTrials.gov NCT01087307.

  5. Large-scale human skin lipidomics by quantitative, high-throughput shotgun mass spectrometry

    PubMed Central

    Sadowski, Tomasz; Klose, Christian; Gerl, Mathias J.; Wójcik-Maciejewicz, Anna; Herzog, Ronny; Simons, Kai; Reich, Adam; Surma, Michal A.

    2017-01-01

    The lipid composition of human skin is essential for its function; however the simultaneous quantification of a wide range of stratum corneum (SC) and sebaceous lipids is not trivial. We developed and validated a quantitative high-throughput shotgun mass spectrometry-based platform for lipid analysis of tape-stripped SC skin samples. It features coverage of 16 lipid classes; total quantification to the level of individual lipid molecules; high reproducibility and high-throughput capabilities. With this method we conducted a large lipidomic survey of 268 human SC samples, where we investigated the relationship between sampling depth and lipid composition, lipidome variability in samples from 14 different sampling sites on the human body and finally, we assessed the impact of age and sex on lipidome variability in 104 healthy subjects. We found sebaceous lipids to constitute an abundant component of the SC lipidome as they diffuse into the topmost SC layers forming a gradient. Lipidomic variability with respect to sampling depth, site and subject is considerable, and mainly accredited to sebaceous lipids, while stratum corneum lipids vary less. This stresses the importance of sampling design and the role of sebaceous lipids in skin studies. PMID:28266621

  6. Analyzing reflectance spectra of human skin in legal medicine

    NASA Astrophysics Data System (ADS)

    Belenki, Liudmila; Sterzik, Vera; Schulz, Katharina; Bohnert, Michael

    2013-01-01

    Our current research in the framework of an interdisciplinary project focuses on modelling the dynamics of the hemoglobin reoxygenation process in post-mortem human skin by reflectance spectrometry. The observations of reoxygenation of hemoglobin in livores after postmortem exposure to a cold environment relate the reoxygenation to the commonly known phenomenon that the color impression of livores changes from livid to pink under low ambient temperatures. We analyze the spectra with respect to a physical model describing the optical properties of human skin, discuss the dynamics of the reoxygenation, and propose a phenomenological model for reoxygenation. For additional characterization of the reflectance spectra, the curvature of the local minimum and maximum in the investigated spectral range is considered. There is a strong correlation between the curvature of specra at a wavelength of 560 nm and the concentration of O2-Hb. The analysis is carried out via C programs, as well as MySQL database queries in Java EE, JDBC, Matlab, and Python.

  7. In vitro human skin segmentation and drug concentration-skin depth profiles.

    PubMed

    Melero, Ana; Hahn, Tsambika; Schaefer, Ulrich F; Schneider, Marc

    2011-01-01

    Highly optimized methods for skin segmentation are provided using tape stripping in combination with infrared absorption measurements for stratum corneum (SC) and cryosectioning for deeper skin layers. Furthermore, an example is calculated for demonstration of the respective procedures.

  8. Permeability of the reconstructed human epidermis model Episkin in comparison to various human skin preparations.

    PubMed

    Netzlaff, Frank; Kaca, Monika; Bock, Udo; Haltner-Ukomadu, Eleonore; Meiers, Peter; Lehr, Claus-Michael; Schaefer, Ulrich F

    2007-04-01

    The objective of this work was to compare the barrier function of the small diameter reconstructed human epidermis model Episkin (d=12 mm) to human skin in vitro. For that purpose a modification for the Franz diffusion cell (d=15mm) had to be developed so as to allow direct comparison with the following human skin preparations: Full thickness skin (FTS), split thickness skin (STS), heat-separated epidermis (HSE), and trypsin isolated stratum corneum (TISC). Among the tested preparations, HSE appeared to be the most preferable due to its clear morphological structure and ease of preparation. The lipid profile of HSE and Episkin was analyzed and showed significant differences in terms of cholesterol, ceramides and triglycerides contents, whereas cholesterol esters and fatty acids were not different. Permeation data with HSE and Episkin were then gathered using caffeine and testosterone. Both test compounds permeated much faster through Episkin than through HSE. Moreover, opposed to Episkin, HSE differentiated between the two test compounds. In spite of the remarkable progress in developing RHEs in the past years at this time Episkin can obviously not yet fully replace human skin for in vitro permeability experiments.

  9. The Development of Skin Conductance Fear Conditioning in Children from Ages 3 to 8 Years

    PubMed Central

    Gao, Yu; Raine, Adrian; Venables, Peter H.; Dawson, Michael E.; Mednick, Sarnoff A.

    2009-01-01

    Although fear conditioning is an important psychological construct implicated in behavioral and emotional problems little is known about how it develops in early childhood. Using a differential, partial reinforcement conditioning paradigm, this longitudinal study assessed skin conductance conditioned responses in 200 children at ages 3, 4, 5, 6, and 8 years. Results demonstrated that in both boys and girls: (1) fear conditioning increased across age, particularly from ages 5 to 6 years, (2) the three components of skin conductance fear conditioning that reflect different degrees of automatic and controlled cognitive processes exhibited different developmental profiles, and (3) individual differences in arousal, orienting, and the unconditioned response were associated with individual differences in conditioning, with the influence of orienting increasing at later ages. This first longitudinal study of the development of skin conductance fear conditioning in children both demonstrates that children as young as age 3 years evidence fear conditioning in a difficult acquisition paradigm, and that different sub-components of skin conductance conditioning have different developmental trajectories. PMID:20121876

  10. The expression of miR-124 increases in aged skin to cause cell senescence and it decreases in squamous cell carcinoma.

    PubMed

    Harada, Miho; Jinnin, Masatoshi; Wang, Zhongzhi; Hirano, Ayaka; Tomizawa, Yukiko; Kira, Tomomi; Igata, Toshikatsu; Masuguchi, Shinichi; Fukushima, Satoshi; Ihn, Hironobu

    2017-01-16

    Skin senescence is induced by various factors including intrinsic aging and extrinsic aging. The current study compared the expression of microRNAs in young facial skin and senescent facial skin, and this study identified skin aging-related microRNAs. According to the results from a microRNA PCR Array, miR-124 was the microRNA that increased the most in senescent skin compared to young skin. Real-time PCR with a greater number of samples indicated that the increase in miR-124 levels in senescent facial skin was statistically significant. In situ hybridization was performed, and results indicated that the signal for miR-124 was evident in keratinocytes of senescent skin but not in those of young skin. The morphology of cultured normal human epidermal keratinocytes (NHEKs) transfected with a miR-124 mimic changed to an enlarged and irregular shape. In addition, the number of NHEKs positive for senescence-associated β-galactosidase (SA-β-gal) increased significantly as a result of the overexpression of the miR-124 mimic. The expression of miR-124 increased in UVB-irradiated NHEKs compared to controls in a dose-dependent manner. Expression of miR-124 in A431, a human cutaneous squamous cell carcinoma (SCC) cell line, decreased significantly compared to that in NHEKs. Forced overexpression of miR-124 as a result of the transfection of a miR-124 mimic in A431 resulted in the significant suppression of the proportion of cancer cells. The current results indicated that miR-124 increases as a result of cell senescence and that it decreases during tumorigenesis. The effect of supplementation of miR-124 in an SCC cell line suggests that senescence induction therapy with microRNA may be a new therapeutic approach for treatment of SCC.

  11. UV exposure modulates hemidesmosome plasticity, contributing to long-term pigmentation in human skin.

    PubMed

    Coelho, Sergio G; Valencia, Julio C; Yin, Lanlan; Smuda, Christoph; Mahns, Andre; Kolbe, Ludger; Miller, Sharon A; Beer, Janusz Z; Zhang, Guofeng; Tuma, Pamela L; Hearing, Vincent J

    2015-05-01

    Human skin colour, ie pigmentation, differs widely among individuals, as do their responses to various types of ultraviolet radiation (UV) and their risks of skin cancer. In some individuals, UV-induced pigmentation persists for months to years in a phenomenon termed long-lasting pigmentation (LLP). It is unclear whether LLP is an indicator of potential risk for skin cancer. LLP seems to have similar features to other forms of hyperpigmentation, eg solar lentigines or age spots, which are clinical markers of photodamage and risk factors for precancerous lesions. To investigate what UV-induced molecular changes may persist in individuals with LLP, clinical specimens from non-sunburn-inducing repeated UV exposures (UVA, UVB or UVA + UVB) at 4 months post-exposure (short-term LLP) were evaluated by microarray analysis and dataset mining. Validated targets were further evaluated in clinical specimens from six healthy individuals (three LLP+ and three LLP-) followed for more than 9 months (long-term LLP) who initially received a single sunburn-inducing UVA + UVB exposure. The results support a UV-induced hyperpigmentation model in which basal keratinocytes have an impaired ability to remove melanin that leads to a compensatory mechanism by neighbouring keratinocytes with increased proliferative capacity to maintain skin homeostasis. The attenuated expression of SOX7 and other hemidesmosomal components (integrin α6β4 and plectin) leads to increased melanosome uptake by keratinocytes and points to a spatial regulation within the epidermis. The reduced density of hemidesmosomes provides supporting evidence for plasticity at the epidermal-dermal junction. Altered hemidesmosome plasticity, and the sustained nature of LLP, may be mediated by the role of SOX7 in basal keratinocytes. The long-term sustained subtle changes detected are modest, but sufficient to create dramatic visual differences in skin colour. These results suggest that the hyperpigmentation phenomenon

  12. UV exposure modulates hemidesmosome plasticity, contributing to long-term pigmentation in human skin

    PubMed Central

    Coelho, Sergio G.; Valencia, Julio C.; Yin, Lanlan; Smuda, Christoph; Mahns, Andre; Kolbe, Ludger; Miller, Sharon A.; Beer, Janusz Z.; Zhang, Guofeng; Tuma, Pamela L.; Hearing, Vincent J.

    2014-01-01

    Human skin color, i.e. pigmentation, differs widely among individuals as do their responses to various types of ultraviolet radiation (UV) and their risks of skin cancer. In some individuals UV-induced pigmentation persists for months to years in a phenomenon termed long-lasting pigmentation (LLP). It is unclear whether LLP is an indicator of potential risk for skin cancer. LLP seems to have similar features to other forms of hyperpigmentation, e.g. solar lentigines or age spots, which are clinical markers of photodamage and risk factors for precancerous lesions. To investigate what UV-induced molecular changes may persist in individuals with LLP, clinical specimens from non-sunburn-inducing repeated UV exposures (UVA, UVB or UVA+UVB) at 4 months post-exposure (short-term LLP) were evaluated by microarray analysis and dataset mining. Validated targets were further evaluated in clinical specimens from 6 healthy individuals (3 LLP+ and 3 LLP-) followed for more than 9 months (long-term LLP) who initially received a single sunburn-inducing UVA+UVB exposure. The results support a UV-induced hyperpigmentation model in which basal keratinocytes have an impaired ability to remove melanin that leads to a compensatory mechanism by neighboring keratinocytes with increased proliferative capacity to maintain skin homeostasis. The attenuated expression of SOX7 and other hemidesmosomal components (integrin α6β4 and plectin) leads to increased melanosome uptake by keratinocytes and points to a spatial regulation within the epidermis. The reduced density of hemidesmosomes provides supporting evidence for plasticity at the epidermal-dermal junction. Altered hemidesmosome plasticity, and the sustained nature of LLP, may be mediated by the role of SOX7 in basal keratinocytes. The long-term sustained subtle changes detected are modest, but sufficient to create dramatic visual differences in skin color. These results suggest that the hyperpigmentation phenomenon leading to increased

  13. Laser system for optical biopsy and in-vivo study of the human skin

    NASA Astrophysics Data System (ADS)

    Borisova, Ekaterina G.; Avramov, Lachezar A.

    2001-04-01

    The aim of this study was to perform a preliminary evaluation of the diagnostic potential of noninvasive laser-induced autofluorescence spectroscopy (LIAFS) for human skin in vivo. The autofluorescence characterization of tissue relies on different spectral properties of tissue. It was demonstrated a differentiation between normal skin and skin with vitaligo. In our experimental investigation of the autofluorescence spectrum of human skin in vivo a nitrogen laser with excitation wavelength 337 nm was used. Two fluorescence bands were observed at 440 and 490 nm, these were attributed to reduced nicotinamide adenine dinucleotide (NADH) and collagen. The intensity of the NADH emission band was markedly reduced in the skin with vitaligo compared with the normal skin, which could indicate different redox conditions in skin with vitaligo. The autofluorescence spectrum of human skin depends on the main internal absorbers, which are blood and melanin. In this study was described the effect caused by melanin content on the shape of the autofluorescence spectrum of human skin. Human skin fluorescence spectrum might provide dermatologists with important information and such investigations are successfully used now in skin disease diagnostics, in investigation of the environmental factor impact or for evaluation of treatment efficiency. The goal of this work is optimization of detection and diagnosis of hollow organs and skin.

  14. Ageing of the human hypothalamus.

    PubMed

    Swaab, D F

    1995-01-01

    The various hypothalamic nuclei show very different patterns of change in ageing. These patterns are a basis for changes in biological rhythms, hormones, autonomous functions or behavior. The suprachiasmatic nucleus (SCN) coordinates circadian and circannual rhythms. A marked seasonal and circadian variation in the vasopressin (AVP) cell number of the SCN was observed in relation to the variation in photoperiod. During normal ageing, the circadian variation and number of AVP-expressing neurons in the SCN decreases. The sexually dimorphic nucleus (SDN), intermediate nucleus or INAH-1 is localized between the supraoptic and paraventricular nucleus (PVN). In adult men the SDN is twice as large as in adult women. In girls, the SDN shows a first period of decreasing cell numbers during prepubertal development, leading to sexual dimorphism. During ageing a decrease in cell number is found in both sexes. The cells of the supraoptic nucleus and PVN produce AVP or oxytocin and coexpress tyrosine hydroxylase. These nuclei are examples of neuron populations that seem to stay perfectly intact in ageing. Parvicellular corticotropin-releasing-hormone (CRH)-containing neurons are found throughout the PVN. CRH neurons in the PVN are activated in the course of ageing, as indicated by their increase in number and AVP coexpression. Part of the infundibular (or arcuate) nucleus, the subventricular nucleus, contains hypertrophic neurons in postmenopausal women. The hypertrophied neurons contain neurokinin-B (NKB), substance P and estrogen receptors and probably act on LHRH neurons as interneurons. The NKB neurons may also be involved in the initiation of menopausal flushes. The nucleus tuberalis lateralis might be involved in feeding behavior and metabolism.(ABSTRACT TRUNCATED AT 250 WORDS)

  15. In vivo confirmation of hydration-induced changes in human-skin thickness, roughness and interaction with the environment.

    PubMed

    Dąbrowska, Agnieszka K; Adlhart, Christian; Spano, Fabrizio; Rotaru, Gelu-Marius; Derler, Siegfried; Zhai, Lina; Spencer, Nicholas D; Rossi, René M

    2016-09-15

    The skin properties, structure, and performance can be influenced by many internal and external factors, such as age, gender, lifestyle, skin diseases, and a hydration level that can vary in relation to the environment. The aim of this work was to demonstrate the multifaceted influence of water on human skin through a combination of in vivo confocal Raman spectroscopy and images of volar-forearm skin captured with the laser scanning confocal microscopy. By means of this pilot study, the authors have both qualitatively and quantitatively studied the influence of changing the depth-dependent hydration level of the stratum corneum (SC) on the real contact area, surface roughness, and the dimensions of the primary lines and presented a new method for characterizing the contact area for different states of the skin. The hydration level of the skin and the thickness of the SC increased significantly due to uptake of moisture derived from liquid water or, to a much lesser extent, from humidity present in the environment. Hydrated skin was smoother and exhibited higher real contact area values. The highest rates of water uptake were observed for the upper few micrometers of skin and for short exposure times.

  16. Daily intake of Jeju groundwater improves the skin condition of the model mouse for human atopic dermatitis.

    PubMed

    Tanaka, Akane; Jung, Kyungsook; Matsuda, Akira; Jang, Hyosun; Kajiwara, Naoki; Amagai, Yosuke; Oida, Kumiko; Ahn, Ginnae; Ohmori, Keitaro; Kang, Kyung-goo; Matsuda, Hiroshi

    2013-03-01

    Drinking water is an important nutrient for human health. The mineral ingredients included in drinking water may affect the physical condition of people. Various kinds of natural water are in circulation as bottled water in developed countries; however, its influence on clinical conditions of patients with certain diseases has not been fully evaluated. In this study, effects of the natural groundwater from Jeju Island on clinical symptoms and skin barrier function in atopic dermatitis (AD) were evaluated. NC/Tnd mice, a model for human AD, with moderate to severe dermatitis were used. Mice were given different natural groundwater or tap water for 8 weeks from 4 weeks of age. Clinical skin severity scores were recorded every week. Scratching analysis and measurement of transepidermal water loss were performed every other week. The pathological condition of the dorsal skin was evaluated histologically. Real-time polymerase chain reaction analysis was performed for cytokine expression in the affected skin. The epidermal hyperplasia and allergic inflammation were reduced in atopic mice supplied with Jeju groundwater when compared to those supplied with tap water or other kinds of natural groundwater. The increase in scratching behavior with the aggravation of clinical severity of dermatitis was favorably controlled. Moreover, transepidermal water loss that reflects skin barrier function was recovered. The early inflammation and hypersensitivity in the atopic skin was alleviated in mice supplied with Jeju groundwater, suggesting its profitable potential on the daily care of patients with skin troubles including AD.

  17. Evaluation of dermal-epidermal skin equivalents ('composite-skin') of human keratinocytes in a collagen-glycosaminoglycan matrix(Integra artificial skin).

    PubMed

    Kremer, M; Lang, E; Berger, A C

    2000-09-01

    Integra artificial skin (Integra LifeSciences Corp., Plainsboro, NJ, USA) is a dermal template consisting of bovine collagen, chondroitin-6-sulphate and a silastic membrane manufactured as Integra. This product has gained widespread use in the clinical treatment of third degree burn wounds and full thickness skin defects of different aetiologies. The product was designed to significantly reduce the time needed to achieve final wound closure in the treatment of major burn wounds, to optimise the sparse autologous donor skin resources and to improve the durable mechanical quality of the skin substitute. The clinical procedure requires two stages. The first step creates a self neodermis, the second creates a self epidermis on the neodermis. However, it is desirable to cover major burn wounds early in a single step by a skin substitute consisting of a dermal equivalent seeded in vitro with autologous keratinocytes ('composite-skin') out of which a full thickness skin develops in vivo.The goal of this experimental study was to develop a method to integrate human keratinocytes in homogeneous distribution and depth into Integra Artificial Skin. The seeded cell-matrix composites were grafted onto athymic mice in order to evaluate their potential to reconstitute a human epidermis in vivo. We were able to demonstrate that the inoculated human keratinocytes reproducibly displayed a homogeneous pattern of distribution, adherence, proliferation and confluence. The cell-matrix composites grafted in this model exhibited good wound adherence, complete healing, minor wound contraction and had the potential to reconstitute an elastic, functional and durable human skin. Histologically we were able to show that the inoculated human keratinocytes in vivo colonised the matrix in a histomorphologically characteristic epidermal pattern (keratomorula, keratinocyte bubbling) and developed a persisting, stratified, keratinising epidermis which immunohistologically proved to be of human

  18. Skin-identical lipids versus petrolatum in the treatment of tape-stripped and detergent-perturbed human skin.

    PubMed

    Lodén, M; Bárány, E

    2000-01-01

    The cutaneous permeability barrier is localized to the stratum corneum interstices and is mediated by lamellar bilayers enriched in cholesterol, free fatty acids and ceramides. Topically applied lipids may interfere with the skin barrier function and formulations containing "skin-identical lipids" have been suggested to facilitate normalization of damaged skin. The aim of the present study was to compare the ability of "skin-identical lipids" in a petrolatum-rich cream base and pure petrolatum to facilitate barrier repair in detergent- and tape-stripped-perturbed human skin. Barrier recovery and inflammation were instrumentally monitored for 14 days as transepidermal water loss and skin blood flow, using an Evaporimeter and a laser Doppler flowmeter, respectively. Treatment with the 2 different products gave no indication that "skin-identical lipids" in a cream base are more efficient than pure petrolatum at promoting normalization in either of the 2 experimentally perturbed areas. This finding may support the hypothesis that different types of skin abnormality should be treated according to the underlying damage.

  19. Fructose 1, 6-diphosphate regulates desmosomal proteins and collagen fibres in human skin equivalents.

    PubMed

    Choi, Hyun; Yang, Seung Ha; Bae, Il-Hong; Park, Ju-Yearl; Kim, Hyoung-June; Noh, Minsoo; Lee, Tae Ryong; Shin, Dong Wook

    2013-12-01

    We previously reported that fructose 1,6-diphosphate (FDP), a glycolytic metabolite, alleviates ultraviolet B-induced oxidative skin damage. Here, we further examined the effects of FDP on skin. FDP decreased the number of desmosomes, whereas it increased collagen fibres in skin equivalents (SEs). FDP significantly decreased the expression of corneodesmosomal components such as desmoglein 1 (DSG1), desmocollin 1 (DSC1) and corneodesmosin (CDSN), and desquamation-related proteases, kallikrein 5 (KLK 5) and kallikrein 7 (KLK7) in normal human epidermal keratinocytes (NHEKs). In addition, FDP treatment increased the phosphorylation of p38 MAPK, but the decreased expression of corneodesmosomal components is not recovered by the treatment of p38 MAPK inhibitors. Interestingly, FDP diminished the amplitude of Ca(2+) fluxes through down-regulation of SERCA2. Taken together, these results suggested that FDP induced a decrease in desmosomes and an increase in collagen fibres similar to the process of chemical peeling, the most common treatments for ageing skin.

  20. Light microscopic, electron microscopic, and immunohistochemical comparison of Bama minipig (Sus scrofa domestica) and human skin.

    PubMed

    Liu, Yu; Chen, Jun-ying; Shang, Hai-tao; Liu, Chang-e; Wang, Yong; Niu, Rong; Wu, Jun; Wei, Hong

    2010-04-01

    Here we sought to evaluate the possibility of using Chinese Bama miniature pig skin as a suitable animal model for human skin. Morphologic features of the skin of Bama miniature pigs resemble those of human skin, including skin layer thickness, development of a superficial vascular system, structure of the dermal-epidermal interface, and extracellular matrix. The characteristics and densities of Langerhans cells, fibroblasts, vascular endothelial cells, and mast cells were similar between Bama pig and human skin. Immunohistochemistry showed that miniature pigs and humans have the same antigenic determinants of human laminin, fibronectin, filaggrin, collagen I, collagen III, collagen IV, and keratin but not CD34, ICAM1, or S100. In addition, collagen type I from Bama miniature pig skin exhibited physicochemical characteristics resembling those of human skin, in regard to HPLC chromatography, UV spectroscopy, amino-acid composition, and SDS-PAGE analysis. Given these results, we concluded that Bama miniature pigs have great potential as a human skin model and for developing dermal substitute materials in wound repair. However, we also observed some disparities between the skin of Bama miniature pigs and humans, including pigment cell distribution, sweat gland types, and others. Therefore, further studies are needed to completely evaluate the effects of these interspecies differences on the actual application of the model.

  1. Reconstructed human epidermis for skin absorption testing: results of the German prevalidation study.

    PubMed

    Schäfer-Korting, Monika; Bock, Udo; Gamer, Armin; Haberland, Annekathrin; Haltner-Ukomadu, Eleonore; Kaca, Monika; Kamp, Hennicke; Kietzmann, Manfred; Korting, Hans Christian; Krächter, Hans-Udo; Lehr, Claus-Michael; Liebsch, Manfred; Mehling, Annette; Netzlaff, Frank; Niedorf, Frank; Rübbelke, Maria K; Schäfer, Ulrich; Schmidt, Elisabeth; Schreiber, Sylvia; Schröder, Klaus-Rudolf; Spielmann, Horst; Vuia, Alexander

    2006-06-01

    Exposure to chemicals absorbed by the skin can threaten human health. In order to standardise the predictive testing of percutaneous absorption for regulatory purposes, the OECD adopted guideline 428, which describes methods for assessing absorption by using human and animal skin. In this study, a protocol based on the OECD principles was developed and prevalidated by using reconstructed human epidermis (RHE). The permeation of the OECD standard compounds, caffeine and testosterone, through commercially available RHE models was compared to that of human epidermis and animal skin. In comparison to human epidermis, the permeation of the chemicals was overestimated when using RHE. The following ranking of the permeation coefficients for testosterone was obtained: SkinEthic > EpiDerm, EPISKIN > human epidermis, bovine udder skin, pig skin. The ranking for caffeine was: SkinEthic, EPISKIN > bovine udder skin, EpiDerm, pig skin, human epidermis. The inter-laboratory and intra-laboratory reproducibility was good. Long and variable lag times, which are a matter of concern when using human and pig skin, did not occur with RHE. Due to the successful transfer of the protocol, it is now in the validation process.

  2. Rapid observation of unfixed, unstained human skin biopsy specimens with confocal microscopy and visualization

    NASA Astrophysics Data System (ADS)

    Masters, Barry R.; Aziz, David J.; Gmitro, Arthur F.; Kerr, James H.; O'Grady, Terence C.; Goldman, Leon

    1997-10-01

    The use of reflected light confocal microscopy is proposed to rapidly observe unfixed, unstained biopsy specimens of human skin. Reflected light laser scanning confocal microscopy was used to compare a freshly excised, unfixed, unstained biopsy specimen, and in vivo human skin. Optical sections from the ex vivo biopsy specimen of human skin and in vivo human skin were converted to red-green anaglyphs for 3D visualization. Contrast was derived from intrinsic differences in the scattering properties of the organelles and cells within the tissue. Individual cellular layers were observed in both tissues from the surface to the papillary dermis. Confocal microscopy of an unfixed, unstained biopsy specimen showed cells and cell nuclei of the stratum spinosum. Confocal microscopy of in vivo human skin demonstrated optical sectioning through a hair shaft on the upper hand. The combination of reflected light confocal microscopy and 3D visualization with red-green anaglyphs provides a rapid technique for observing fresh biopsies of human skin.

  3. The process of ageing reflected by histological changes in the skin.

    PubMed

    Bonta, Marinela; Daina, Lucia; Muţiu, Gabriela

    2013-01-01

    Structural and functional alterations, as well as changes occurring in the aspect of the skin during the ageing process, are due to some complex mechanisms, determined by intrinsic and extrinsic factors, which act synergistically. This study aims to analyze the histological changes of collagen and elastic fibers and of skin vasculature that occur in time, during the process of ageing. Fragments of skin have been collected from subjects of both sexes and of different ages, totaling 121 samples from different body regions. The following stains were used: Modified Goldner's Masson trichrome, Ferric Orcein-Hematoxylin and the combined stains Orcein-Goldner's trichrome. As the process of ageing advances, collagen fibers become thinner and change their aspect; at advanced age, the lysis of collagen fibers and their thickening in the deep dermis is present, as they become more fibrous. Elastic fibers show the tendency of fragmentation at more advanced age, gradually change their tinctorial affinity and reduce in amount; in the deep dermis, they tend to thicken progressively, in the presence of discrete elastolysis processes that evolve steadily and irreversibly. Thus, processes of elastic fibers degeneration and lysis run faster by comparison with those of collagen fibers degeneration. With ageing, a progressive reduction of dermis vasculature is present, due to a reduction in the number and size of vascular vessels, which is in its turn associated with the progressive alterations of vascular walls components, changes that advance until the function of the vessel ceases.

  4. Improvement of the experimental setup to assess cutaneous bioavailability on human skin models: dynamic protocol.

    PubMed

    Dreher, F; Patouillet, C; Fouchard, F; Zanini, M; Messager, A; Roguet, R; Cottin, M; Leclaire, J; Benech-Kieffer, F

    2002-01-01

    Human skin models, such as EpiDerm and Episkin, are not easily mounted into static or dynamic diffusion cells that are commonly used to perform bioavailability studies with human skin ex vivo. For various reasons, such as fragility, small sample size, and other morphological constraints, skin absorption studies with human skin models are often carried out on the delimited skin surface obtained by gluing a ring onto the reconstituted epidermis and manually exchanging the receptor solution. However, such an experimental setup is prone to artifacts. Discontinuous removal of the receptor fluid leads to alternating sink conditions, and an area of application smaller than the area in contact with the receptor fluid, as well as imperfect seal of the glued ring, may result in inaccurate penetration rates. Human skin models were shown to be relatively easily mounted into In-Line cells (PermeGear Inc.), vertical diffusion cells which appear to be appropriately designed for such a purpose. In-Line cells allowed accurate determination of solute penetration as well as automated sampling of receptor fluid. Excised human skin can be mounted into these cells as well, making it possible to compare penetration rates through different types of skin samples under identical conditions. Using mannitol as a reference compound, penetration profiles and epidermal distribution similar to those obtained with human skin ex vivo were obtained both with EpiDerm and Episkin. Under the present conditions, human skin models were more permeable to mannitol than excised human skin, which was only slightly permeable to mannitol. Due to these experimental innovations and to the good agreement with the absorption characteristics through human skin ex vivo, EpiDerm and Episkin seem to be promising human skin models for testing the cutaneous bioavailability of topical products in vitro.

  5. Sympathetic regulation during thermal stress in human aging and disease

    PubMed Central

    Greaney, Jody L.; Kenney, W. Larry; Alexander, Lacy M.

    2015-01-01

    Humans control their core temperature within a narrow range via precise adjustments of the autonomic nervous system. In response to changing core and/or skin temperature, several critical thermoregulatory reflex effector responses are initiated and include shivering, sweating, and changes in cutaneous blood flow. Cutaneous vasomotor adjustments, mediated by modulations in sympathetic nerve activity (SNA), aid in the maintenance of thermal homeostasis during cold and heat stress since (1) they serve as the first line of defense of body temperature and are initiated before other thermoregulatory effectors, and (2) they are on the efferent arm of non-thermoregulatory reflex systems, aiding in the maintenance of blood pressure and organ perfusion. This review article highlights the sympathetic responses of humans to thermal stress, with a specific focus on primary aging as well as impairments that occur in both heart disease and type 2 diabetes mellitus. Age- and pathology-related changes in efferent muscle and skin SNA during cold and heat stress, measured directly in humans using microneurography, are discussed. PMID:26627337

  6. Newborn human skin fibroblasts senesce in vitro without acquiring adult growth factor requirements

    SciTech Connect

    Wharton, W.

    1984-01-01

    Cultures of human fibroblasts were prepared from chest skin obtained either from newborns (less than 3 months old) or adults (more than 35 years old) and maintained in vitro until they senesced. Adult cells grew logarithmically in medium supplemented with whole blood serum but not with platelet-poor plasma. Early passage cells obtained from newborns grew equally well in either plasma- or serum-supplemented medium. The difference in growth factor requirements between adult and newborn cells persisted through the lifespan of the cells; i.e., newborn cells did not develop adult hormonal requirements when maintained in culture. Thus, in vitro cellular aging can be distinguished from some types of differentiation.

  7. A new dermocosmetic containing retinaldehyde, delta-tocopherol glucoside and glycylglycine oleamide for managing naturally aged skin: results from in vitro to clinical studies

    PubMed Central

    Rouvrais, Céline; Bacqueville, Daniel; Bogdanowicz, Patrick; Haure, Marie-José; Duprat, Laure; Coutanceau, Christine; Castex-Rizzi, Nathalie; Duplan, Hélène; Mengeaud, Valérie; Bessou-Touya, Sandrine

    2017-01-01

    Introduction Natural aging of skin tissues, the addition of the cumulative action of the time and radiation exposure result in skin atrophy, wrinkles and degeneration of the extracellular matrix (ECM). The aim of the study was to investigate the beneficial effect of a combination containing retinaldehyde (RAL), delta-tocopherol glucoside (delta-TC) and glycylglycine ole-amide (GGO) and of a dermocosmetic containing the combination. Materials and methods The protective effect of the combination was assessed through in vitro gene expression of ultraviolet (UV)-irradiated fibroblasts. A skin aging assay using UV light on ex vivo skin samples and a clinical study conducted in 36 women aged from 35 to 55 years with a minimum of level 4 to a maximum of level 6 on the crow’s feet photoscale assessed the antiaging effect of the dermocosmetic. Results When added to UV-irradiated fibroblasts, the combination substantially improved the ECM in activating the elastin fiber production (fibrillin 2, fibulin 1 and 5 and lysyl oxidase-like 2) as well as that of proteins involved in the cellular ECM interactions (integrin b1, paxillin and actin a2). An ex vivo photodamaged human skin model showed that the dermocosmetic formulation containing the combination of the active ingredients protected the elastic network against UV-induced alterations including both elastin and fibrillin-rich fibers in the dermis. A daily application of the dermocosmetic for 2 months on naturally aged skin resulted in a statistically significant improvement (p<0.05) of visible signs of aging comprising crow’s feet, wrinkles and periocular fine lines. Finally, the formulation was well tolerated. Conclusion The dermocosmetic containing RAL, delta-TC and GGO provides a substantial benefit in the daily care of naturally aged skin in women aged 35–55 years. PMID:28203099

  8. Resonance Raman spectroscopic evaluation of skin carotenoids as a biomarker of carotenoid status for human studies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Resonance Raman Spectroscopy (RRS) is a non-invasive method that has been developed to assess carotenoid status in human tissues including human skin in vivo. Skin carotenoid status, as assessed by RRS, has been suggested as a promising biomarker for use in human studies. This manuscript describes...

  9. The Development of Skin Conductance Fear Conditioning in Children from Ages 3 to 8 Years

    ERIC Educational Resources Information Center

    Gao, Yu; Raine, Adrian; Venables, Peter H.; Dawson, Michael E.; Mednick, Sarnoff A.

    2010-01-01

    Although fear conditioning is an important psychological construct implicated in behavioral and emotional problems, little is known about how it develops in early childhood. Using a differential, partial reinforcement conditioning paradigm, this longitudinal study assessed skin conductance conditioned responses in 200 children at ages 3, 4, 5, 6,…

  10. In vivo transformation of human skin with human papillomavirus type 11 from condylomatot acuminata

    SciTech Connect

    Kreider, J.W.; Howett, M.K.; Lill, N.L.; Bartlett, G.L.; Zaino, R.J.; Sedlacek, T.V.; Mortel, R.

    1986-08-01

    Human papillomaviruses (HPVs) have been implicated in the development of a number of human malignancies, but direct tests of their involvement have not been possible. The authors describe a system in which human skin from various skin from various sites was infected with HPV type 11 (HPV-11) extracted from vulvar condylomata and was grafted beneath the renal capsule of athymic mice. Most of the skin grafts so treated underwent morphological transformation, resulting in the development of condylomata identical to those which occur spontaneously in patients. Foreskins responded with the most vigorous proliferative response to HPV-11. The lesions produced the characteristic intranuclear group-specific antigen of papillomaviruses. Both dot blot and Southern blot analysis of DNA from the lesions revealed the presence of HPV-11 DNA in the transformed grafts. These results demonstrate the first laboratory system for the study of the interaction of human skin with an HPV. The method may be useful in understanding the mechanisms of HPV transformation and replication and is free of the ethical restraints which have impeded study. This system will allow the direct study of factors which permit neoplastic progression of HPV-induced cutaneous lesions in human tissues.

  11. The Impact of Aging on Human Sexuality.

    ERIC Educational Resources Information Center

    Rienzo, Barbara A.

    1985-01-01

    Lay persons and professionals need to be educated on the effects of aging on human sexuality. Effective communication techniques and accurate sexuality information can lead to prevention of psychosocial problems and sexual dysfunction. (Author/DF)

  12. In vivo optical elastography: stress and strain imaging of human skin lesions

    NASA Astrophysics Data System (ADS)

    Es'haghian, Shaghayegh; Gong, Peijun; Kennedy, Kelsey M.; Wijesinghe, Philip; Sampson, David D.; McLaughlin, Robert A.; Kennedy, Brendan F.

    2015-03-01

    Probing the mechanical properties of skin at high resolution could aid in the assessment of skin pathologies by, for example, detecting the extent of cancerous skin lesions and assessing pathology in burn scars. Here, we present two elastography techniques based on optical coherence tomography (OCT) to probe the local mechanical properties of skin. The first technique, optical palpation, is a high-resolution tactile imaging technique, which uses a complaint silicone layer positioned on the tissue surface to measure spatially-resolved stress imparted by compressive loading. We assess the performance of optical palpation, using a handheld imaging probe on a skin-mimicking phantom, and demonstrate its use on human skin. The second technique is a strain imaging technique, phase-sensitive compression OCE that maps depth-resolved mechanical variations within skin. We show preliminary results of in vivo phase-sensitive compression OCE on a human skin lesion.

  13. Enhanced skin permeation of naltrexone by pulsed electromagnetic fields in human skin in vitro.

    PubMed

    Krishnan, Gayathri; Edwards, Jeffrey; Chen, Yan; Benson, Heather A E

    2010-06-01

    The aim of the present study was to evaluate the skin permeation of naltrexone (NTX) under the influence of a pulsed electromagnetic field (PEMF). The permeation of NTX across human epidermis and a silicone membrane in vitro was monitored during and after application of the PEMF and compared to passive application. Enhancement ratios of NTX human epidermis permeation by PEMF over passive diffusion, calculated based on the AUC of cumulative NTX permeation to the receptor compartment verses time for 0-4 h, 4-8 h, and over the entire experiment (0-8 h) were 6.52, 5.25, and 5.66, respectively. Observation of the curve indicated an initial enhancement of NTX permeation compared to passive delivery whilst the PEMF was active (0-4 h). This was followed by a secondary phase after termination of PEMF energy (4-8 h) in which there was a steady increase in NTX permeation. No significant enhancement of NTX penetration across silicone membrane occurred with PEMF application in comparison to passively applied NTX. In a preliminary experiment PEMF enhanced the penetration of 10 nm gold nanoparticles through the stratum corneum as visualized by multiphoton microscopy. This suggests that the channels through which the nanoparticles move must be larger than the 10 nm diameter of these rigid particles.

  14. Transplantation of human skin microbiota in models of atopic dermatitis

    PubMed Central

    Myles, Ian A.; Williams, Kelli W.; Reckhow, Jensen D.; Jammeh, Momodou L.; Pincus, Nathan B.; Sastalla, Inka; Saleem, Danial; Stone, Kelly D.; Datta, Sandip K.

    2016-01-01

    Atopic dermatitis (AD) is characterized by reduced barrier function, reduced innate immune activation, and susceptibility to Staphylococcus aureus. Host susceptibility factors are suggested by monogenic disorders associated with AD-like phenotypes and can be medically modulated. S. aureus contributes to AD pathogenesis and can be mitigated by antibiotics and bleach baths. Recent work has revealed that the skin microbiome differs significantly between healthy controls and patients with AD, including decreased Gram-negative bacteria in AD. However, little is known about the potential therapeutic benefit of microbiome modulation. To evaluate whether parameters of AD pathogenesis are altered after exposure to different culturable Gram-negative bacteria (CGN) collected from human skin, CGN were collected from healthy controls and patients with AD. Then, effects on cellular and culture-based models of immune, epithelial, and bacterial function were evaluated. Representative strains were evaluated in the MC903 mouse model of AD. We found that CGN taken from healthy volunteers but not from patients with AD were associated with enhanced barrier function, innate immunity activation, and control of S. aureus. Treatment with CGN from healthy controls improved outcomes in a mouse model of AD. These findings suggest that a live-biotherapeutic approach may hold promise for treatment of patients with AD. PMID:27478874

  15. Advanced UV Absorbers for the Protection of Human Skin.

    PubMed

    Hüglin, Dietmar

    The increasing awareness of the damaging effects of UV radiation to human skin triggered the market introduction of new cosmetic UV absorbers. This article summarizes the outcome of a multi-year research program, in which the author contributed to the development of different new UV filters. First of all, the molecular design and the basic properties of bis-ethylhexyloxyphenol methoxyphenyl triazine (BEMT) will be presented. This oil-soluble filter, which today is widely used in both beach products and skin care products, exhibits inherent photostability and strong broad-spectrum UV-A+B absorbance. Based on the concept of micronized organic UV absorbers, the UV-B filter tris biphenyl triazine (TBPT) will be introduced. At present TBPT exhibits the highest efficacy of all cosmetic UV absorbers in the market (measured by area under the UV spectrum). Finally, the concept of liposomogenic UV absorbers will be featured. This approach was developed to create water-resistant UV filters, as liposomogenic structures are thought to integrate into the lipids of the horny layer. Due to prohibitively high costs, this technology did not result in a commercial product so far.

  16. Evaporation of volatile organic compounds from human skin in vitro.

    PubMed

    Gajjar, Rachna M; Miller, Matthew A; Kasting, Gerald B

    2013-08-01

    The specific evaporation rates of 21 volatile organic compounds (VOCs) from either human skin or a glass substrate mounted in modified Franz diffusion cells were determined gravimetrically. The diffusion cells were positioned either on a laboratory bench top or in a controlled position in a fume hood, simulating indoor and outdoor environments, respectively. A data set of 54 observations (34 skin and 20 glass) was assembled and subjected to a correlation analysis employing 5 evaporative mass transfer relationships drawn from the literature. Models developed by Nielsen et al. (Prediction of isothermal evaporation rates of pure volatile organic compounds in occupational environments: a theoretical approach based on laminar boundary layer theory. Ann Occup Hyg 1995;39:497-511.) and the U.S. Environmental Protection Agency (Peress, Estimate evaporative losses from spills. Chem Eng Prog 2003; April: 32-34.) were found to be the most effective at correlating observed and calculated evaporation rates under the various conditions. The U.S. EPA model was selected for further use based on its simplicity. This is a turbulent flow model based only on vapor pressure and molecular weight of the VOC and the effective air flow rate u. Optimum values of u for the two laboratory environments studied were 0.23 m s(-1) (bench top) and 0.92 m s(-1) (fume hood).

  17. 3D bioprinting of functional human skin: production and in vivo analysis.

    PubMed

    Cubo, Nieves; Garcia, Marta; Del Cañizo, Juan F; Velasco, Diego; Jorcano, Jose L

    2016-12-05

    Significant progress has been made over the past 25 years in the development of in vitro-engineered substitutes that mimic human skin, either to be used as grafts for the replacement of lost skin, or for the establishment of in vitro human skin models. In this sense, laboratory-grown skin substitutes containing dermal and epidermal components offer a promising approach to skin engineering. In particular, a human plasma-based bilayered skin generated by our group, has been applied successfully to treat burns as well as traumatic and surgical wounds in a large number of patients in Spain. There are some aspects requiring improvements in the production process of this skin; for example, the relatively long time (three weeks) needed to produce the surface required to cover an extensive burn or a large wound, and the necessity to automatize and standardize a process currently performed manually. 3D bioprinting has emerged as a flexible tool in regenerative medicine and it provides a platform to address these challenges. In the present study, we have used this technique to print a human bilayered skin using bioinks containing human plasma as well as primary human fibroblasts and keratinocytes that were obtained from skin biopsies. We were able to generate 100 cm(2), a standard P100 tissue culture plate, of printed skin in less than 35 min (including the 30 min required for fibrin gelation). We have analysed the structure and function of the printed skin using histological and immunohistochemical methods, both in 3D in vitro cultures and after long-term transplantation to immunodeficient mice. In both cases, the generated skin was very similar to human skin and, furthermore, it was indistinguishable from bilayered dermo-epidermal equivalents, handmade in our laboratories. These results demonstrate that 3D bioprinting is a suitable technology to generate bioengineered skin for therapeutical and industrial applications in an automatized manner.

  18. Ultraviolet radiation, aging and the skin: prevention of damage by topical cAMP manipulation.

    PubMed

    Amaro-Ortiz, Alexandra; Yan, Betty; D'Orazio, John A

    2014-05-15

    Being the largest and most visible organ of the body and heavily influenced by environmental factors, skin is ideal to study the long-term effects of aging. Throughout our lifetime, we accumulate damage generated by UV radiation. UV causes inflammation, immune changes, physical changes, impaired wound healing and DNA damage that promotes cellular senescence and carcinogenesis. Melanoma is the deadliest form of skin cancer and among the malignancies of highest increasing incidence over the last several decades. Melanoma incidence is directly related to age, with highest rates in individuals over the age of 55 years, making it a clear age-related disease. In this review, we will focus on UV-induced carcinogenesis and photo aging along with natural protective mechanisms that reduce amount of "realized" solar radiation dose and UV-induced injury. We will focus on the theoretical use of forskolin, a plant-derived pharmacologically active compound to protect the skin against UV injury and prevent aging symptoms by up-regulating melanin production. We will discuss its use as a topically-applied root-derived formulation of the Plectranthus barbatus (Coleus forskolii) plant that grows naturally in Asia and that has long been used in various Aryuvedic teas and therapeutic preparations.

  19. Ultraviolet radiation, aging and the skin: prevention of damage by topical cAMP manipulation

    PubMed Central

    Amaro-Ortiz, Alexandra; Yan, Betty; D’Orazio, John A.

    2015-01-01

    Being the largest and most visible organ of the body and heavily influenced by environmental factors, skin is ideal to study long-term effects of aging. Throughout our lifetime, we accumulate damage generated by UV radiation. UV causes inflammation, immune changes, physical changes, impaired wound healing and DNA damage that promotes cellular senescence and carcinogenesis. Melanoma is the deadliest form of skin cancer and among the malignancies of highest increasing incidence over the last several decades. Melanoma incidence is directly related to age, with highest rates in individuals over the age of 55 years, making it a clear age-related disease. In this review, we will focus on UV-induced carcinogenesis and photo aging along with natural protective mechanisms that reduce amount of “realized” solar radiation dose and UV-induced injury. We will focus on the theoretical use of forskolin, a plant-derived pharmacologically active compound to protect the skin against UV injury and prevent aging symptoms by up-regulating melanin production. We will discuss its use as a topically-applied root-derived formulation of the Plectranthus barbatus (Coleus forskolii) plant that grows naturally in Asia and that has long been used in various Aryuvedic teas and therapeutic preparations. PMID:24838074

  20. Melanin and blood concentration in human skin studied by multiple regression analysis: experiments.

    PubMed

    Shimada, M; Yamada, Y; Itoh, M; Yatagai, T

    2001-09-01

    Knowledge of the mechanism of human skin colour and measurement of melanin and blood concentration in human skin are needed in the medical and cosmetic fields. The absorbance spectrum from reflectance at the visible wavelength of human skin increases under several conditions such as a sunburn or scalding. The change of the absorbance spectrum from reflectance including the scattering effect does not correspond to the molar absorption spectrum of melanin and blood. The modified Beer-Lambert law is applied to the change in the absorbance spectrum from reflectance of human skin as the change in melanin and blood is assumed to be small. The concentration of melanin and blood was estimated from the absorbance spectrum reflectance of human skin using multiple regression analysis. Estimated concentrations were compared with the measured one in a phantom experiment and this method was applied to in vivo skin.

  1. Melanin and blood concentration in human skin studied by multiple regression analysis: experiments

    NASA Astrophysics Data System (ADS)

    Shimada, M.; Yamada, Y.; Itoh, M.; Yatagai, T.

    2001-09-01

    Knowledge of the mechanism of human skin colour and measurement of melanin and blood concentration in human skin are needed in the medical and cosmetic fields. The absorbance spectrum from reflectance at the visible wavelength of human skin increases under several conditions such as a sunburn or scalding. The change of the absorbance spectrum from reflectance including the scattering effect does not correspond to the molar absorption spectrum of melanin and blood. The modified Beer-Lambert law is applied to the change in the absorbance spectrum from reflectance of human skin as the change in melanin and blood is assumed to be small. The concentration of melanin and blood was estimated from the absorbance spectrum reflectance of human skin using multiple regression analysis. Estimated concentrations were compared with the measured one in a phantom experiment and this method was applied to in vivo skin.

  2. Characterizing human skin blood flow regulation in response to different local skin temperature perturbations.

    PubMed

    Wu, Y; Nieuwenhoff, M D; Huygen, F J P M; van der Helm, F C T; Niehof, S; Schouten, A C

    2017-05-01

    Small nerve fibers regulate local skin blood flow in response to local thermal perturbations. Small nerve fiber function is difficult to assess with classical neurophysiological tests. In this study, a vasomotor response model in combination with a heating protocol was developed to quantitatively characterize the control mechanism of small nerve fibers in regulating skin blood flow in response to local thermal perturbation. The skin of healthy subjects' hand dorsum (n=8) was heated to 42°C with an infrared lamp, and then naturally cooled down. The distance between the lamp and the hand was set to three different levels in order to change the irradiation intensity on the skin and implement three different skin temperature rise rates (0.03°C/s, 0.02°C/s and 0.01°C/s). A laser Doppler imager (LDI) and a thermographic video camera recorded the temporal profile of the skin blood flow and the skin temperature, respectively. The relationship between the skin blood flow and the skin temperature was characterized by a vasomotor response model. The model fitted the skin blood flow response well with a variance accounted for (VAF) between 78% and 99%. The model parameters suggested a similar mechanism for the skin blood flow regulation with the thermal perturbations at 0.03°C/s and 0.02°C/s. But there was an accelerated skin vasoconstriction after a slow heating (0.01°C/s) (p-value<0.05). An attenuation of the skin vasodilation was also observed in four out of the seven subjects during the slow heating (0.01°C/s). Our method provides a promising way to quantitatively assess the function of small nerve fibers non-invasively and non-contact.

  3. Elderly and sun-affected skin. Distinguishing between changes caused by aging and changes caused by habitual exposure to sun.

    PubMed Central

    Jackson, R.

    2001-01-01

    OBJECTIVE: To review and distinguish between skin changes produced by aging and changes produced by habitual exposure to sun. QUALITY OF EVIDENCE: The literature was searched from 1969 to 1999 for articles on dermatoheliosis and sun-damaged skin. Surprisingly few were found comparing the difference between elderly skin and sun-damaged skin. A few articles focused on certain small aspects of sun-damaged skin. Many excellent articles described particular changes (e.g., actinic keratosis), but few covered all the changes due to aging and to sun. MAIN MESSAGE: Skin changes due to aging can be distinguished from those due to sun damage. All changes due to sun exposure can be grouped under the term dermatoheliosis; five parts of the skin are involved: epidermis (actinic keratosis), dermis (solar elastosis), blood vessels (telangiectasia), sebaceous glands (solar comedones), and melanocytes (diffuse or mottled brown patches). Habitual exposure to sun and a white skin are prerequisites for developing these changes. Knowing the difference between changes caused by sun and by aging can help physicians predict which patients are most likely to get skin cancers. CONCLUSION: Knowledge of these common skin changes will help physicians diagnose and manage the skin abnormalities of elderly people and of people with dermatoheliosis. PMID:11421052

  4. In vivo confocal Raman spectroscopy study of the vitamin A derivative perfusion through human skin

    NASA Astrophysics Data System (ADS)

    dos Santos, Laurita; Téllez Soto, Claudio A.; Favero, Priscila P.; Martin, Airton A.

    2016-03-01

    In vivo confocal Raman spectroscopy is a powerful non-invasive technique able to analyse the skin constituents. This technique was applied to transdermal perfusion studies of the vitamin A derivative in human skin. The composition of the stratum corneum (lipid bilayer) is decisive for the affinity and transport of the vitamin through skin. The vitamin A is significantly absorbed by human skin when applied with water in oil emulsion or hydro-alcoholic gel. The purpose of this study is to elucidate the behaviour of vitamin A derivative into human skin without the presence of enhancers. The results showed that the intensity band of the derivative (around 1600 cm-1), which represents the -C=O vibrational mode, was detected in different stratum corneum depths (up to 20 μm). This Raman peak of vitamin A derivative has non-coincident band with the Raman spectra of the skin epidermis, demonstrating that compound penetrated in forearm skin.

  5. A Randomized, Double-blind, Placebo-controlled Clinical Trial Evaluating an Oral Anti-aging Skin Care Supplement for Treating Photodamaged Skin

    PubMed Central

    Sigler, Monya L.; Hino, Peter D.; Moigne, Anne Le; Dispensa, Lisa

    2016-01-01

    Objective: Evaluate an anti-aging skin care supplement on the appearance of photodamaged skin. Design: Randomized, double-blind, placebo-controlled clinical trial. Following a one-month washout period, subjects received two anti-aging skin care formula tablets (total daily dose: marine complex 210mg, vitamin C 54mg, zinc 4mg) or placebo daily for 16 weeks. Subjects were restricted from products/procedures that may affect the condition/appearance of skin, including direct facial sun or tanning bed exposure. Participants utilized a standardized facial cleanser and SPF15 moisturizer. Setting: Single study center (Texas, United States; June-November 2007). Participants: Healthy women aged 35 to 60 years (mean, 50 years), Fitzpatrick skin type I-IV, modified Glogau type II—III. Measurements: Subjects were assessed at Weeks 6, 12, and 16 on clinical grading (0-10 VAS), bioinstrumentation, digital photography, and self-assessments. Analysis of variance with treatment in the model was used for between-group comparisons (alpha P≤0.05). Results: Eighty-two anti-aging skin care formula subjects and 70 placebo subjects completed the study. Significant differences in change from baseline to Week 16 scores were observed for clinical grading of overall facial appearance (0.26; P<0.0001), radiant complexion (0.59; P<0.0001), periocular wrinkles (0.08; P<0.05), visual (0.56; P<0.0001) and tactile (0.48; P<0.0001) roughness, and mottled hyperpigmentation (0.15; P<0.001) favoring the subjects in the anti-aging skin care supplement group. Ultrasound skin density (Week 16) was significantly reduced for placebo versus anti-aging skin care supplement group (-1.4% vs. 0%; P<0.01). Other outcomes were not significant. Mild gastrointestinal symptoms possibly related to the anti-aging skin care supplement (n=1) and placebo (n=2) were observed. Conclusion: Women with photodamaged skin receiving anti-aging skin care supplement showed significant improvements in the appearance of facial

  6. Skin pentosidine and telomere length do not covary with age in a long-lived seabird.

    PubMed

    Rattiste, Kalev; Klandorf, Hillar; Urvik, Janek; Sepp, Tuul; Asghar, Muhammad; Hasselquist, Dennis; Cooey, Crissa; Hõrak, Peeter

    2015-08-01

    The questions about why and how senescence occurs in the wild are among the most pertinent ones in evolutionary ecology. Telomere length is a commonly used marker for aging, while other biomarkers of aging have received considerably less attention. Here we studied how another potent indicator of aging-skin pentosidine concentration-relates to age and blood telomere length in a long-lived seabird with well-documented reproductive senescence. We found no associations between telomere length, skin pentosidine and chronological age in male common gulls (Larus canus), aging from 2 to 30 years. However, the variance in telomere length was 4.6 times higher among the birds older than 13 years, which hints at relaxed selection on telomere length among the birds that have passed their prime age of reproduction. These results suggest that physiological and chronological ages may be largely uncoupled in our study system. Furthermore, our findings do not support a hypothesis about the presence of a common physiological factor (e.g., such as oxidative stress) that would cause covariation between two independent markers of aging.

  7. Maintenance of the normal flora of human skin grafts transplanted to mice.

    PubMed

    Kearney, J N; Gowland, G; Holland, K T; Cunliffe, W J

    1982-10-01

    Full-thickness human cadaver skin was maintained on the dorso-lateral thoracic region of hairless mice whose immune rejection mechanism was suppressed using anti-mouse-thymocyte globulin. The bacterial profile of the pregrafted skin did not differ significantly from the normal human microflora. In contrast, the murine skin exhibited quantitative and qualitative differences from the human flora, in particular by the complete absence of Propionibacterium acnes, the dominant bacterium on sebum-rich areas of human skin. The normal microbial profile of the human grafts was maintained throughout the experimental period despite the novel environmental milieu. There was little contamination of the grafts from the normal murine flora. It was concluded that the grafted human skin would provide a realistic model for studying the ecology of human cutaneous micro-organisms.

  8. Expression of Human Skin-Specific Genes Defined by Transcriptomics and Antibody-Based Profiling

    PubMed Central

    Edqvist, Per-Henrik D.; Fagerberg, Linn; Hallström, Björn M.; Danielsson, Angelika; Edlund, Karolina; Uhlén, Mathias

    2014-01-01

    To increase our understanding of skin, it is important to define the molecular constituents of the cell types and epidermal layers that signify normal skin. We have combined a genome-wide transcriptomics analysis, using deep sequencing of mRNA from skin biopsies, with immunohistochemistry-based protein profiling to characterize the landscape of gene and protein expression in normal human skin. The transcriptomics and protein expression data of skin were compared to 26 (RNA) and 44 (protein) other normal tissue types. All 20,050 putative protein-coding genes were classified into categories based on patterns of expression. We found that 417 genes showed elevated expression in skin, with 106 genes expressed at least five-fold higher than that in other tissues. The 106 genes categorized as skin enriched encoded for well-known proteins involved in epidermal differentiation and proteins with unknown functions and expression patterns in skin, including the C1orf68 protein, which showed the highest relative enrichment in skin. In conclusion, we have applied a genome-wide analysis to identify the human skin-specific proteome and map the precise localization of the corresponding proteins in different compartments of the skin, to facilitate further functional studies to explore the molecular repertoire of normal skin and to identify biomarkers related to various skin diseases. PMID:25411189

  9. The assessment of human skin biomatrixes using raman spectroscopy method

    NASA Astrophysics Data System (ADS)

    Timchenko, E. V.; Timchenko, P. E.; Volova, L. T.; Dolgushkin, D. A.; Shalkovskaya, P. Y.; Pershutkina, S. V.; Nefedova, I. F.

    2017-01-01

    There are presented the results of the analysis of the implants made of human skin by Raman scattering method. The main spectral distinctions of bioimplants by using various methods for their manufacture are shown at wavenumbers 1062 cm-1, 1645 cm-1, 1260 cm-1, 850 cm-1, 863 cm-1, corresponding to components that are important for the quality of implant: glycosaminoglycans, amide type I, amide type III, asymmetrical association C-O-S of vibration of glycosaminoglycans GAGs, tyrosine and a C-C stretching of proline ring, ribose. Has been carried out two-dimensional analysis of optical coefficients providing an opportunity to control the quality of cutaneous implants in the process of manufacturing it, and detailed analysis of Raman scattering spectroscopy.

  10. [The effect of aging on the peripheral functions in farmers and chain saw operators. Part 2. Age-related changes in skin temperature and hyperemia time after pressing the nail (author's transl)].

    PubMed

    Kasamatsu, T; Miyashita, K; Shiomi, S; Iwata, H

    1981-05-01

    Vibration hazards which arise after exposure to mechanical vibration comprise various types of disorders, the most common of which are peripheral circulatory disturbances. It is now well recognized that aging effects all organ systems of the human body. The present study was therefore performed to assess the effects of aging on finger skin temperature and on hyperemia time after pressing the nail, both of which reflect peripheral circulatory functions. The subjects were 88 farmers and 86 chain saw operators ranging in age from 30 to 69 years, and 27 healthy persons aged 21 to 37 years as controls. Data were evaluated before and after cold water immersion tests in which the hand was immersed in 10 degrees C water for 10 minutes. The results obtained were as follows: 1) Before the test, skin temperature was negatively correlated with age, and hyperemia time was positively correlated with age in both farmers and chain saw operators but not in the case of the control subjects. 2)The skin temperature became lower, and hyperemia time grew longer with advancing age in both farmers and chain saw operators before and after the immersion tests. In comparison of the average skin temperature and hyperemia time between farmers and chain saw operators classified by age, the average skin temperature in chain saw operators was significantly lower than that in farmers, and the average hyperemia time in chain saw operators was significantly longer than that in farmers of every age group after the immersion test. The results suggest that we should take age-related changes into consideration to some degree when we evaluate the finger skin temperature and hyperemia time in diagnosing peripheral circulatory disturbances.

  11. Multivariate Models for Prediction of Human Skin Sensitization Hazard#

    EPA Science Inventory

    One of the lnteragency Coordinating Committee on the Validation of Alternative Method's (ICCVAM) top priorities is the development and evaluation of non-animal approaches to identify potential skin sensitizers. The complexity of biological events necessary to produce skin sensiti...

  12. Metabolically Competent Human Skin Models: Activation and Genotoxicity of Benzo[a]pyrene

    PubMed Central

    Henkler, Frank

    2013-01-01

    The polycyclic aromatic hydrocarbon (PAH) benzo[a]pyrene (BP) is metabolized into a complex pattern of BP derivatives, among which the ultimate carcinogen (+)-anti-BP-7,8-diol-9,10-epoxide (BPDE) is formed to certain extents. Skin is frequently in contact with PAHs and data on the metabolic capacity of skin tissue toward these compounds are inconclusive. We compared BP metabolism in excised human skin, commercially available in vitro 3D skin models and primary 2D skin cell cultures, and analyzed the metabolically catalyzed occurrence of seven different BP follow-up products by means of liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). All models investigated were competent to metabolize BP, and the metabolic profiles generated by ex vivo human skin and skin models were remarkably similar. Furthermore, the genotoxicity of BP and its derivatives was monitored in these models via comet assays. In a full-thickness skin, equivalent BP-mediated genotoxic stress was generated via keratinocytes. Cultured primary keratinocytes revealed a level of genotoxicity comparable with that of direct exposure to 50–100nM of BPDE. Our data demonstrate that the metabolic capacity of human skin ex vivo, as well as organotypic human 3D skin models toward BP, is sufficient to cause significant genotoxic stress and thus cutaneous bioactivation may potentially contribute to mutations that ultimately lead to skin cancer. PMID:23148024

  13. Specificity of procaine and ester hydrolysis by human, minipig, and rat skin and liver.

    PubMed

    Jewell, Christopher; Ackermann, Chrisita; Payne, N Ann; Fate, Gwendolyn; Voorman, Richard; Williams, Faith M

    2007-11-01

    The capacity of human, minipig, and rat skin and liver subcellular fractions to hydrolyze the anesthetic ester procaine was compared with carboxylesterase substrates 4-methylumbelliferyl-acetate, phenylvalerate, and para-nitrophenylacetate and the arylesterase substrate phenylacetate. Rates of procaine hydrolysis by minipig and human skin microsomal and cytosolic fractions were similar, with rat displaying higher activity. Loperamide inhibited procaine hydrolysis by human skin, suggesting involvement of human carboxylesterase hCE2. The esterase activity and inhibition profiles in the skin were similar for minipig and human, whereas rat had a higher capacity to metabolize esters and a different inhibition profile. Minipig and human liver and skin esterase activity was inhibited principally by paraoxon and bis-nitrophenyl phosphate, classical carboxylesterase inhibitors. Rat skin and liver esterase activity was inhibited additionally by phenylmethylsulfonyl fluoride and the arylesterase inhibitor mercuric chloride, indicating a different esterase profile. These results have highlighted the potential of skin to hydrolyze procaine following topical application, which possibly limits its pharmacological effect. Skin from minipig used as an animal model for assessing transdermal drug preparations had similar capacity to hydrolyze esters to human skin.

  14. Skin abscess

    MedlinePlus

    Abscess - skin; Cutaneous abscess; Subcutaneous abscess; MRSA - abscess; Staph infection - abscess ... Skin abscesses are common and affect people of all ages. They occur when an infection causes pus ...

  15. Heat waves, aging, and human cardiovascular health.

    PubMed

    Kenney, W Larry; Craighead, Daniel H; Alexander, Lacy M

    2014-10-01

    This brief review is based on a President's Lecture presented at the Annual Meeting of the American College of Sports Medicine in 2013. The purpose of this review was to assess the effects of climate change and consequent increases in environmental heat stress on the aging cardiovascular system. The earth's average global temperature is slowly but consistently increasing, and along with mean temperature changes come increases in heat wave frequency and severity. Extreme passive thermal stress resulting from prolonged elevations in ambient temperature and prolonged physical activity in hot environments creates a high demand on the left ventricle to pump blood to the skin to dissipate heat. Even healthy aging is accompanied by altered cardiovascular function, which limits the extent to which older individuals can maintain stroke volume, increase cardiac output, and increase skin blood flow when exposed to environmental extremes. In the elderly, the increased cardiovascular demand during heat waves is often fatal because of increased strain on an already compromised left ventricle. Not surprisingly, excess deaths during heat waves 1) occur predominantly in older individuals and 2) are overwhelmingly cardiovascular in origin. Increasing frequency and severity of heat waves coupled with a rapidly growing at-risk population dramatically increase the extent of future untoward health outcomes.

  16. Imaging of sebaceous glands of human skin by three-dimensional ultrasound microscopy and its relation to elasticity.

    PubMed

    Kumagai, Kazutoshi; Koike, Hideyuki; Kudo, Yukina; Nagaoka, Ryo; Kubo, Kiyono; Kobayashi, Kazuto; Saijo, Yoshifumi

    2011-01-01

    High frequency ultrasound imaging has realized high resolution in vivo imaging of the biological tissues at a microscopic level. Human skin structure, especially sebaceous glands at the deep part of the dermis, was observed by three-dimensional ultrasound microscopy with the central frequency of 120 MHz. The visco-elasticity and surface sebum level of the observed region were measured by established testing devices. Both sebaceous glands density and surface sebum level were higher in cheek than those in forearm. The viscosity of forearm was lower than that of cheek. These results suggest that sebaceous glands may act as cushions of the skin besides their classical role of secreting sebum and some hormones. High frequency ultrasound imaging contributes to the evaluation of human skin aging.

  17. Influence of IR radiation on the carotenoid content in human skin

    NASA Astrophysics Data System (ADS)

    Darvin, M. E.; Zastrov, L.; Gonchukov, S. A.; Lademann, J.

    2009-12-01

    It is shown that the infrared irradiation decreases the content of β-carotene and lycopene carotenoids in human skin. A decrease in the content of β-carotene and lycopene may indicate that the IR radiation, as well as the UV radiation, is capable of forming free radicals in human skin. The investigations were performed in vivo using the technique of resonance Raman scattering developed by us for the noninvasive determination of antioxidant potential in skin.

  18. Previous chronic exogenous glucocorticoid administration in vivo does not affect functional characteristics and cellular lifespan of human skin fibroblasts in vitro.

    PubMed

    Pratsinis, Harris; Dimozi, Anastasia; Pilichos, Konstantinos; Tsagarakis, Stylianos; Yiacoumettis, Andreas M; Kletsas, Dimitris

    2011-06-01

    Excess of glucocorticoids (GCs) has been reported to lead to skin atrophy and impaired wound healing. The present study investigates whether human skin fibroblasts suffer permanent damages due to a long-term exposure to GC excess. Fibroblasts obtained from patients being under GC treatment for periods over one year were cultured under standard conditions in vitro, and studied regarding pivotal parameters involved in skin homeostasis and aging, i.e. collagen production, cell proliferation, and cellular replicative lifespan. No statistical differences were observed regarding these functions compared to those of normal human skin fibroblasts. Furthermore, no differences between normal and patient-derived cells were observed regarding their sensitivity to a supra-physiological cortisol concentration. In conclusion, the prolonged exposure of human skin fibroblasts in vivo to high concentrations of exogenously-administered GC does not lead to persistent adverse effects on their physiology.

  19. Bioavailability of natural carotenoids in human skin compared to blood.

    PubMed

    Meinke, Martina C; Darvin, Maxim E; Vollert, Henning; Lademann, Jürgen

    2010-10-01

    Skin functions and structure are significantly influenced by nutrients. Antioxidants protect the supportive layer of the skin against any damaging irradiation effects and the action of free radicals. A lack of suitable methods means that the pharmacokinetic properties of systemically applied carotenoids transferred into the skin remain poorly understood. In this study, a natural kale extract or placebo oil were given orally to 22 healthy volunteers for 4 weeks. Carotenoid bioaccessibility was evaluated using non-invasive resonance Raman spectroscopy on the palm and forehead skin. For the analysis of the blood serum, the standard HPLC method was used. The blood and skin levels of the carotenoids increased significantly during the study but compared to the blood serum values, increases in skin were delayed and depended on the dermal area as well as on the carotenoid. Lycopene, measured as being low in the extract, increases more in the skin compared to the blood indicating that the natural mixture of the extract stabilizes the antioxidative network in the skin. After supplementation had ended, the carotenoids decreased much faster in the blood than in the skin. The delayed decrease in the skin may indicate a peripheral buffer function of the skin for carotenoids.

  20. Five-year incidence of age-related maculopathy in relation to iris, skin or hair colour, and skin sun sensitivity: the Blue Mountains Eye Study.

    PubMed

    Wang, Jie Jin; Jakobsen, Kirsten; Smith, Wayne; Mitchell, Paul

    2003-08-01

    This study aimed to assess longitudinal associations between iris,hair and skin colour, plus skin sensitivity to sun and the 5-year incidence of age-related maculopathy (ARM). Of 3654 baseline Blue Mountains Eye Study participants (aged 49+ years), 2335 survivors (75.1%) were re-examined after 5 years. Retinal photographs were graded using the Wisconsin ARM Grading System and incident ARM lesions confirmed using side-by-side grading.Iris/skin/hair colour was assessed and skin sensitivity questions were asked at baseline. After adjusting for age, sex and smoking, no significant associations were found between iris or hair colour and incident late or early ARM. Compared to persons with fair skin, those with very fair skin had an increased risk of developing geographical atrophy (odds ratio [OR] 3.5,95% confidence interval [CI] 1.2-10.4).However, persons with sun-related skin damage were less likely than those without to develop indistinct soft drusen (OR 0.6, 95% CI 0.4-0.9). Longitudinal data provide no support for the previously reported cross-sectional association between iris colour and ARM.

  1. Hydrogen sulphide and phosphine interactions with human skin in vitro: Application to hazardous material incident decision making for skin decontamination.

    PubMed

    Gaskin, Sharyn; Heath, Linda; Pisaniello, Dino; Evans, Richard; Edwards, John W; Logan, Michael; Baxter, Christina

    2016-03-03

    Accidental or intentional releases of toxic gases can have significant public health consequences and emergency resource demands. Management of exposed individuals during hazardous material incidents should be risk and evidence based, but there are knowledge gaps in relation to dermal absorption of gases and management advice for potentially exposed individuals. Using a modified Organization for Economic Co-operation and Development (OECD) in vitro toxicology protocol with human donor skin, this article reports on two common and odorous chemicals, hydrogen sulphide and phosphine. Results show that undamaged human skin provides a good barrier to hydrogen sulphide (up to 800 ppm) and phosphine (up to 1000 ppm) penetration for up to 30 min exposures, with little variability in the presence of clothing or in elevated temperature and humidity conditions. A practical guideline template for skin decontamination has been developed, and implications of the research for first responders are outlined.

  2. Monomethylarsonous acid inhibited endogenous cholesterol biosynthesis in human skin fibroblasts

    SciTech Connect

    Guo, Lei; Xiao, Yongsheng; Wang, Yinsheng

    2014-05-15

    Human exposure to arsenic in drinking water is a widespread public health concern, and such exposure is known to be associated with many human diseases. The detailed molecular mechanisms about how arsenic species contribute to the adverse human health effects, however, remain incompletely understood. Monomethylarsonous acid [MMA(III)] is a highly toxic and stable metabolite of inorganic arsenic. To exploit the mechanisms through which MMA(III) exerts its cytotoxic effect, we adopted a quantitative proteomic approach, by coupling stable isotope labeling by amino acids in cell culture (SILAC) with LC-MS/MS analysis, to examine the variation in the entire proteome of GM00637 human skin fibroblasts following acute MMA(III) exposure. Among the ∼ 6500 unique proteins quantified, ∼ 300 displayed significant changes in expression after exposure with 2 μM MMA(III) for 24 h. Subsequent analysis revealed the perturbation of de novo cholesterol biosynthesis, selenoprotein synthesis and Nrf2 pathways evoked by MMA(III) exposure. Particularly, MMA(III) treatment resulted in considerable down-regulation of several enzymes involved in cholesterol biosynthesis. In addition, real-time PCR analysis showed reduced mRNA levels of select genes in this pathway. Furthermore, MMA(III) exposure contributed to a distinct decline in cellular cholesterol content and significant growth inhibition of multiple cell lines, both of which could be restored by supplementation of cholesterol to the culture media. Collectively, the present study demonstrated that the cytotoxicity of MMA(III) may arise, at least in part, from the down-regulation of cholesterol biosynthesis enzymes and the resultant decrease of cellular cholesterol content. - Highlights: • MMA(III)-induced perturbation of the entire proteome of GM00637 cells is studied. • Quantitative proteomic approach revealed alterations of multiple cellular pathways. • MMA(III) inhibits de novo cholesterol biosynthesis. • MMA

  3. In vitro dermal absorption of pyrethroid pesticides in human and rat skin

    EPA Science Inventory

    Dermal exposure to pyrethroid pesticides can occur during manufacture and application. This study examined the in vitro dermal absorption of pyrethroids using rat and human skin. Dermatomed skin from adult male Long Evans rats or human cadavers was mounted in flowthrough diffusi...

  4. Large field of view multiphoton microscopy of human skin

    NASA Astrophysics Data System (ADS)

    Balu, Mihaela; Mikami, Hideharu; Hou, Jue; Potma, Eric O.; Tromberg, Bruce J.

    2016-03-01

    Clinical examination crucially relies on the ability to quickly examine large tissue areas and rapidly zoom in to regions of interest. Skin lesions often show irregularity in color and appearance in general, especially when they start to progress towards malignancy. Large field of view (FOV) and automatic translation of the imaging area are critical in the assessment of the entire lesion. Imaging of limited FOVs of the lesion can easily result in false negative diagnosis. We present a multiphoton microscope based on two-photon excited fluorescence and second-harmonic generation that images FOVs of about 0.8 mm2 (without stitching adjacent FOVs) at speeds of 10 frames/second (800 x 800 pixels) with lateral and axial resolutions of 0.5 μm and 2.5 μm, respectively. The main novelty of this instrument is the design of the scan head, which includes a fast galvanometric scanner, relay optics, a beam expander and a high NA objective lens. We optimized the system based on the Olympus 25x, 1.05NA water immersion lens, that features a long working distance of 1 mm. Proper tailoring of the beam expander, which consists of the scan and tube lens elements, enables scaling of the FOV. The design criteria include a flat wavefront of the beam, minimum field curvature, and suppressed spherical aberrations. All aberrations in focus are below the Marechal criterion of 0.07λ rms for diffraction-limited performance. We demonstrate the practical utility of this microscope by ex-vivo imaging of wide FOVs in normal human skin.

  5. A broad-spectrum sunscreen prevents UVA radiation-induced gene expression in reconstructed skin in vitro and in human skin in vivo.

    PubMed

    Marionnet, Claire; Grether-Beck, Susanne; Seité, Sophie; Marini, Alessandra; Jaenicke, Thomas; Lejeune, François; Bastien, Philippe; Rougier, André; Bernerd, Françoise; Krutmann, Jean

    2011-06-01

    The efficacy of sunscreens to protect against ultraviolet (UV) A radiation is usually assessed by measuring erythema formation and pigmentation. The biological relevance of these endpoints for UVA-induced skin damage, however, is not known. We therefore carried out two complementary studies to determine UVA protection provided by a broad-spectrum sunscreen product at a molecular level by studying UVA radiation-induced gene expression. One study was performed on human reconstructed skin in vitro with a semi-global gene expression analysis of 227 genes in fibroblasts and 244 in keratinocytes. The second one was conducted in vivo in human volunteers and focused on genes involved in oxidative stress response and photo-ageing (haeme oxygenase-1, superoxide dismutase-2, glutathione peroxidase, catalase, matrix metalloproteinase-1). In-vitro UVA radiation induced modulation of genes involved in extracellular matrix homeostasis, oxidative stress, heat shock responses, cell growth, inflammation and epidermal differentiation. Sunscreen pre-application abrogated or significantly reduced these effects, as underlined by unsupervised clustering analysis. The in vivo study confirmed that the sunscreen prevented UVA radiation-induced transcriptional expression of the five studied genes. These findings indicate the high efficacy of a broad-spectrum sunscreen in protecting human skin against UVA-induced gene responses and suggest that this approach is a biologically relevant complement to existing methods.

  6. Palladium and Platinum Nanoparticles Attenuate Aging-Like Skin Atrophy via Antioxidant Activity in Mice

    PubMed Central

    Shibuya, Shuichi; Ozawa, Yusuke; Watanabe, Kenji; Izuo, Naotaka; Toda, Toshihiko; Yokote, Koutaro; Shimizu, Takahiko

    2014-01-01

    Cu-Zn superoxide dismutase (Sod1) loss causes a redox imbalance as it leads to excess superoxide generation, which results in the appearance of various aging-related phenotypes, including skin atrophy. Noble metal nanoparticles, such as palladium (Pd) and platinum (Pt) nanoparticles, are considered to function as antioxidants due to their strong catalytic activity. In Japan, a mixture of Pd and Pt nanoparticles called PAPLAL has been used to treat chronic diseases over the past 60 years. In the present study, we investigated the protective effects of PAPLAL against aging-related skin pathologies in mice. Transdermal PAPLAL treatment reversed skin thinning associated with increased lipid peroxidation in Sod1−/− mice. Furthermore, PAPLAL normalized the gene expression levels of Col1a1, Mmp2, Has2, Tnf-α, Il-6, and p53 in the skin of the Sod1−/− mice. Pt nanoparticles exhibited marked SOD and catalase activity, while Pd nanoparticles only displayed weak SOD and catalase activity in vitro. Although the SOD and catalase activity of the Pt nanoparticles significantly declined after they had been oxidized in air, a mixture of Pd and Pt nanoparticles continued to exhibit SOD and catalase activity after oxidation. Importantly, a mixture of Pd and Pt nanoparticles with a molar ratio of 3 or 4 to 1 continued to exhibit SOD and catalase activity after oxidation, indicating that Pd nanoparticles prevent the oxidative deterioration of Pt nanoparticles. These findings indicate that PAPLAL stably suppresses intrinsic superoxide generation both in vivo and in vitro via SOD and catalase activity. PAPLAL is a potentially powerful tool for the treatment of aging-related skin diseases caused by oxidative damage. PMID:25333617

  7. Palladium and platinum nanoparticles attenuate aging-like skin atrophy via antioxidant activity in mice.

    PubMed

    Shibuya, Shuichi; Ozawa, Yusuke; Watanabe, Kenji; Izuo, Naotaka; Toda, Toshihiko; Yokote, Koutaro; Shimizu, Takahiko

    2014-01-01

    Cu-Zn superoxide dismutase (Sod1) loss causes a redox imbalance as it leads to excess superoxide generation, which results in the appearance of various aging-related phenotypes, including skin atrophy. Noble metal nanoparticles, such as palladium (Pd) and platinum (Pt) nanoparticles, are considered to function as antioxidants due to their strong catalytic activity. In Japan, a mixture of Pd and Pt nanoparticles called PAPLAL has been used to treat chronic diseases over the past 60 years. In the present study, we investigated the protective effects of PAPLAL against aging-related skin pathologies in mice. Transdermal PAPLAL treatment reversed skin thinning associated with increased lipid peroxidation in Sod1-/- mice. Furthermore, PAPLAL normalized the gene expression levels of Col1a1, Mmp2, Has2, Tnf-α, Il-6, and p53 in the skin of the Sod1-/- mice. Pt nanoparticles exhibited marked SOD and catalase activity, while Pd nanoparticles only displayed weak SOD and catalase activity in vitro. Although the SOD and catalase activity of the Pt nanoparticles significantly declined after they had been oxidized in air, a mixture of Pd and Pt nanoparticles continued to exhibit SOD and catalase activity after oxidation. Importantly, a mixture of Pd and Pt nanoparticles with a molar ratio of 3 or 4 to 1 continued to exhibit SOD and catalase activity after oxidation, indicating that Pd nanoparticles prevent the oxidative deterioration of Pt nanoparticles. These findings indicate that PAPLAL stably suppresses intrinsic superoxide generation both in vivo and in vitro via SOD and catalase activity. PAPLAL is a potentially powerful tool for the treatment of aging-related skin diseases caused by oxidative damage.

  8. [Age and aging as incomplete architecture of human ontogenesis].

    PubMed

    Baltes, P B

    1999-12-01

    The focus is on the basic biological-genetic and social-cultural architecture of human development across the life span. The starting point is the frame provided by past evolutionary forces. A first conclusion is that for modern times and the relative brevity of the time windows involved in modernity, further change in human functioning is primarily dependent on the evolution of new cultural forms of knowledge rather than evolution-based changes in the human genome. A second conclusion concerns the general architecture of the life course. Three governing lifespan developmental principles coexist. First, because long-term evolutionary selection evince a negative age correlation, genome-based plasticity and biological potential decrease with age. Second, for growth aspects of human development to extend further into the life span, culture-based resources are required at ever increasing levels. Third, because of age-related losses in biological plasticity and negative effects associated with some principles of learning (e.g., negative transfer), the efficiency of culture is reduced as lifespan development unfolds. Joint application of these principles suggests that the lifespan architecture becomes more and more incomplete with age. Three examples are given to illustrate the implications of the lifespan architecture outlined. The first is a general theory of development involving the orchestration of three component processes and their age-related dynamics: Selection, optimization, and compensation. The second example is theory and research on lifespan intelligence that distinguishes between the biology-based mechanics and culture-based pragmatics of intelligence and specifies distinct age gradients for the two categories of intellectual functioning. The third example considers the goal of evolving a positive biological and cultural scenario for the last phase of life (fourth age). Because of the general lifespan architecture outlined, this objective becomes

  9. Insight into the immunobiology of human skin and functional specialization of skin dendritic cell subsets to innovate intradermal vaccination design.

    PubMed

    Teunissen, M B M; Haniffa, M; Collin, M P

    2012-01-01

    Dendritic cells (DC) are the key initiators and regulators of any immune response which determine the outcome of CD4(+) and CD8(+) T-cell responses. Multiple distinct DC subsets can be distinguished by location, phenotype, and function in the homeostatic and inflamed human skin. The function of steady-state cutaneous DCs or recruited inflammatory DCs is influenced by the surrounding cellular and extracellular skin microenvironment. The skin is an attractive site for vaccination given the extended local network of DCs and the easy access to the skin-draining lymph nodes to generate effector T cells and immunoglobulin-producing B cells for long-term protective immunity. In the context of intradermal vaccination we describe in this review the skin-associated immune system, the characteristics of the different skin DC subsets, the mechanism of antigen uptake and presentation, and how the properties of DCs can be manipulated. This knowledge is critical for the development of intradermal vaccine strategies and supports the concept of intradermal vaccination as a superior route to the conventional intramuscular or subcutaneous methods.

  10. Recent advances in clinical application of optical coherence tomography of human skin

    PubMed Central

    Gambichler, Thilo; Pljakic, Azem; Schmitz, Lutz

    2015-01-01

    Optical coherence tomography (OCT) is an emerging noninvasive imaging method that uses infrared light and interferometric techniques. The method has become increasingly popular in skin research as well as daily dermatology practice. In the present brief review, we focused on recent (2009–2014) OCT studies on the human skin, which included a reasonable sample size and statistics. Twenty-five papers were selected and briefly described OCT of epidermal thickness, skin appendages, wound healing, extracellular matrix and skin fibrosis, vascular malformations, and skin tumors such as basal cell carcinoma, actinic keratoses, and malignant melanoma. PMID:26185462

  11. Aging of the human ovary and testis.

    PubMed

    Perheentupa, Antti; Huhtaniemi, Ilpo

    2009-02-05

    Aging is associated with structural and functional alterations in all organs of the human body. The aging of gonads represents in this respect a special case, because these organs are not functional for the whole lifespan of an individual and their normal function is not indispensable for functions of the rest of the body. Ovarian function lasts for the reproductive life of a woman, i.e., from menarche until menopause. The testicular endocrine function, in contrast, begins already in utero, is interrupted between neonatal life and puberty, and continues thereafter along with spermatogenesis, with only slight decline, until old age. The aging processes of the ovary and testis are therefore very different. We describe in this review the structural and functional alterations in the human ovary and testis upon aging. Special emphasis will be given to clinically significant alterations, which in women concern the causes and consequences of the individual variability of fertility during the latter part of the reproductive age. The clinically important aspect of testicular aging entails the decline of androgen production in aging men.

  12. Three-dimensional confocal fluorescence microscopic visualization of the living human skin

    NASA Astrophysics Data System (ADS)

    Masters, Barry R.

    1995-04-01

    Three-dimensional confocal visualization of living human skin is a new development in the noninvasive imaging of normal and pathological tissue. I have investigated the autofluorescence of in vivo human skin with a laser scanning confocal microscope. An argon ion laser (488 nm) was used for excitation of the natural fluorescence of skin and a 515 nm cut off filter was used to separate the fluorescence from the excitation light. I found that normal skin has a very high autofluorescence. The laser scanning confocal microscope was used to obtain a stack of serial sections through the skin. A stack of optical sections through the hair follicle was reconstructed as well as the three-dimensional reconstruction of the pores of sweat glands. The ability to obtain two and three-dimensional visualizations of in vivo human skin may provide a new tool for noninvasive diagnostics in dermatology.

  13. Insertion Testing of Polyethylene Glycol Microneedle Array into Cultured Human Skin with Biaxial Tension

    NASA Astrophysics Data System (ADS)

    Takano, Naoki; Tachikawa, Hiroto; Miyano, Takaya; Nishiyabu, Kazuaki

    Aiming at the practical use of polyethylene glycol (PEG) microneedles for transdermal drug delivery system (DDS), a testing apparatus for their insertion into cultured human skin has been developed. To simulate the variety of conditions of human skin, biaxial tension can be applied to the cultured human skin. An adopted testing scheme to apply and control the biaxial tension is similar to the deep-draw forming technique. An attention was also paid to the short-time setup of small, thin and wet cultured skin. One dimensional array with four needles was inserted and influence of tension was discussed. It was found that tension, deflection of skin during insertion and original curvature of skin are the important parameters for microneedles array design.

  14. Passiflora tarminiana fruits reduce UVB-induced photoaging in human skin fibroblasts.

    PubMed

    Bravo, Karent; Duque, Luisa; Ferreres, Federico; Moreno, Diego A; Osorio, Edison

    2017-03-01

    Skin aging is a complex process that is strongly affected by UV radiation, which stimulates the production of reactive oxygen species (ROS) in the epidermis and dermis and subsequently causes skin damage. Among the major consequences are increased collagen degradation and reduced collagen synthesis. Previous reports have demonstrated the beneficial effects of polyphenols for healthy skin. Passiflora tarminiana Coppens & V.E. Barney, a species of the Passifloraceae family, is widely distributed in South America and is rich in flavonoids. We show that UVB radiation increases metalloproteinase 1 (MMP-1) and reduces procollagen production in human dermal fibroblast (HDF) cells in a dose- and time-dependent manner. We examined the antioxidant and antiaging effects of the extract and fractions of P. tarminiana fruits. The fractions showed high polyphenol content (620mg EAG/g) and antioxidant activity, as measured by ORAC (4097μmol ET/g) and ABTS (2992μmol ET/g) assays. The aqueous fraction drastically inhibited the collagenase enzyme (IC50 0.43μg/mL). The extract and fractions presented photoprotective effects by reducing UVB-induced MMP-1 production, increasing UVB-inhibited procollagen production, and decreasing ROS production after UVB irradiation in HDF. Finally, the polyphenol contents of the extracts and fractions from P. tarminiana were analyzed by HPLC-DAD-ESI-MS(n), and procyanidins and glycosylated flavonoids were identified.

  15. Skin Corrosion and Irritation Test of Nanoparticles Using Reconstructed Three-Dimensional Human Skin Model, EpiDermTM

    PubMed Central

    Kim, Hyejin; Choi, Jonghye; Lee, Handule; Park, Juyoung; Yoon, Byung-Il; Jin, Seon Mi; Park, Kwangsik

    2016-01-01

    Effects of nanoparticles (NPs) on skin corrosion and irritation using three-dimensional human skin models were investigated based on the test guidelines of Organization for Economic Co-operation and Development (OECD TG431 and TG439). EpiDermTM skin was incubated with NPs including those harboring iron (FeNPs), aluminum oxide (AlNPs), titanium oxide (TNPs), and silver (AgNPs) for a defined time according to the test guidelines. Cell viabilities of EpiDermTM skins were measured by the 3-(4, 5-dimethylthi-azol-2-yl)-2.5-diphenyltetrazolium bromide based method. FeNPs, AlNPs, TNPs, and AgNPs were non-corrosive because the viability was more than 50% after 3 min exposure and more than 15% after 60 min exposure, which are the non-corrosive criteria. All NPs were also non-irritants, based on viability exceeding 50% after 60 min exposure and 42 hr post-incubation. Release of interleukin 1-alpha and histopathological analysis supported the cell viability results. These findings suggest that FeNPs, AlNPs, TNPs, and AgNPs are ‘non-corrosive’ and ‘non-irritant’ to human skin by a globally harmonized classification system. PMID:27818733

  16. The impact of aging on human sexuality.

    PubMed

    Rienzo, B A

    1985-02-01

    Review of gerontological and medical literature reveals the need for education for lay persons and professionals about the effects of the aging process on human sexuality. Primary prevention of psychosocial problems and sexual dysfunction could be abated by including accurate information about sexuality and aging and effective communication techniques in sexuality education programs, including those with young adults. In addition, professional preparation of health educators must include the skills and knowledge needed in this area.

  17. Optical characters and texture maps of skin and the aging mechanism by use of multiphoton microscopy and optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Wu, Shulian; Li, Hui; Zhang, Xiaoman; Huang, Yudian; Xu, Xiaohui

    2012-03-01

    Cutaneous aging is a complicated biological process affecting different constituents of skin, which can be divided into two types: the chronological aging and the photo-aging. The two cutaneous aging processes often co-exist accompanying with each other. The effects are often overlapped including changes in epithelium and dermis. The degeneration of collagen is a major factor in dermal alteration with aging. In this study, multiphoton microscopy (MPM) with its high resolution imaging and optical coherence tomography (OCT) with its depth resolved imaging were used to study the anti-aging dermatology in vivo. It was attempted to make the optical parameter and texture feature to evaluate the process of aging skin using mathematical image processing. The links among optical parameter, spectrum and texture feature in collagen with aging process were established to uncover mechanism of aging skin.

  18. Multiple skin neoplasms in subjects under 40 years of age in Goiania, Brazil.

    PubMed

    Pereira, Samir; Curado, Maria Paula; Ribeiro, Ana Maria Quinteiro

    2015-01-01

    OBJECTIVE To describe the trend for malignant skin neoplasms in subjects under 40 years of age in a region with high ultraviolet radiation indices.METHODS A descriptive epidemiological study on melanoma and nonmelanoma skin cancers that was conducted in Goiania, Midwest Brazil, with 1,688 people under 40 years of age, between 1988 and 2009. Cases were obtained fromRegistro de Câncer de Base Populacional de Goiânia(Goiania's Population-Based Cancer File). Frequency, trends, and incidence of cases with single and multiple lesions were analyzed; transplants and genetic skin diseases were found in cases with multiple lesions.RESULTS Over the period, 1,995 skin cancer cases were observed to found, of which 1,524 (90.3%) cases had single lesions and 164 (9.7%) had multiple lesions. Regarding single lesions, incidence on men was observed to have risen from 2.4 to 3.1/100,000 inhabitants; it differed significantly for women, shifting from 2.3 to 5.3/100,000 (Annual percentage change - [APC] 3.0%, p = 0.006). Regarding multiple lesions, incidence on men was observed to have risen from 0.30 to 0.98/100,000 inhabitants; for women, it rose from 0.43 to 1.16/100,000 (APC 8.6%, p = 0.003). Genetic skin diseases or transplants were found to have been correlated with 10.0% of cases with multiple lesions - an average of 5.1 lesions per patient. The average was 2.5 in cases without that correlation.CONCLUSIONS Skin cancer on women under 40 years of age has been observed to be increasing for both cases with single and multiple lesions. It is not unusual to find multiple tumors in young people - in most cases, they are not associated with genetic skin diseases or transplants. It is necessary to avoid excessive exposure to ultraviolet radiation from childhood.

  19. Multiple skin neoplasms in subjects under 40 years of age in Goiania, Brazil

    PubMed Central

    Pereira, Samir; Curado, Maria Paula; Ribeiro, Ana Maria Quinteiro

    2015-01-01

    OBJECTIVE To describe the trend for malignant skin neoplasms in subjects under 40 years of age in a region with high ultraviolet radiation indices. METHODS A descriptive epidemiological study on melanoma and nonmelanoma skin cancers that was conducted in Goiania, Midwest Brazil, with 1,688 people under 40 years of age, between 1988 and 2009. Cases were obtained from Registro de Câncer de Base Populacional de Goiânia (Goiania’s Population-Based Cancer File). Frequency, trends, and incidence of cases with single and multiple lesions were analyzed; transplants and genetic skin diseases were found in cases with multiple lesions. RESULTS Over the period, 1,995 skin cancer cases were observed to found, of which 1,524 (90.3%) cases had single lesions and 164 (9.7%) had multiple lesions. Regarding single lesions, incidence on men was observed to have risen from 2.4 to 3.1/100,000 inhabitants; it differed significantly for women, shifting from 2.3 to 5.3/100,000 (Annual percentage change – [APC] 3.0%, p = 0.006). Regarding multiple lesions, incidence on men was observed to have risen from 0.30 to 0.98/100,000 inhabitants; for women, it rose from 0.43 to 1.16/100,000 (APC 8.6%, p = 0.003). Genetic skin diseases or transplants were found to have been correlated with 10.0% of cases with multiple lesions – an average of 5.1 lesions per patient. The average was 2.5 in cases without that correlation. CONCLUSIONS Skin cancer on women under 40 years of age has been observed to be increasing for both cases with single and multiple lesions. It is not unusual to find multiple tumors in young people – in most cases, they are not associated with genetic skin diseases or transplants. It is necessary to avoid excessive exposure to ultraviolet radiation from childhood. PMID:26465667

  20. Quantitative analysis of intrinsic skin aging in dermal papillae by in vivo harmonic generation microscopy

    PubMed Central

    Liao, Yi-Hua; Kuo, Wei-Cheng; Chou, Sin-Yo; Tsai, Cheng-Shiun; Lin, Guan-Liang; Tsai, Ming-Rung; Shih, Yuan-Ta; Lee, Gwo-Giun; Sun, Chi-Kuang

    2014-01-01

    Chronological skin aging is associated with flattening of the dermal-epidermal junction (DEJ), but to date no quantitative analysis focusing on the aging changes in the dermal papillae (DP) has been performed. The aim of the study is to determine the architectural changes and the collagen density related to chronological aging in the dermal papilla zone (DPZ) by in vivo harmonic generation microscopy (HGM) with a sub-femtoliter spatial resolution. We recruited 48 Asian subjects and obtained in vivo images on the sun-protected volar forearm. Six parameters were defined to quantify 3D morphological changes of the DPZ, which we analyzed both manually and computationally to study their correlation with age. The depth of DPZ, the average height of isolated DP, and the 3D interdigitation index decreased with age, while DP number density, DP volume, and the collagen density in DP remained constant over time. In vivo high-resolution HGM technology has uncovered chronological aging-related variations in DP, and sheds light on real-time quantitative skin fragility assessment and disease diagnostics based on collagen density and morphology. PMID:25401037

  1. A micromechanical comparison of human and porcine skin before and after preservation by freezing for medical device development

    PubMed Central

    Ranamukhaarachchi, S. A.; Lehnert, S.; Ranamukhaarachchi, S. L.; Sprenger, L.; Schneider, T.; Mansoor, I.; Rai, K.; Häfeli, U. O.; Stoeber, B.

    2016-01-01

    Collecting human skin samples for medical research, including developing microneedle-based medical devices, is challenging and time-consuming. Researchers rely on human skin substitutes and skin preservation techniques, such as freezing, to overcome the lack of skin availability. Porcine skin is considered the best substitute to human skin, but their mechanical resemblance has not been fully validated. We provide a direct mechanical comparison between human and porcine skin samples using a conventional mechano-analytical technique (microindentation) and a medical application (microneedle insertion), at 35% and 100% relative humidity. Human and porcine skin samples were tested immediately after surgical excision from subjects, and after one freeze-thaw cycle at −80 °C to assess the impact of freezing on their mechanical properties. The mechanical properties of fresh human and porcine skin (especially of the stratum corneum) were found to be different for bulk measurements using microindentation; and both types of skin were mechanically affected by freezing. Localized in-plane mechanical properties of skin during microneedle insertion appeared to be more comparable between human and porcine skin samples than their bulk out-of-plane mechanical properties. The results from this study serve as a reference for future mechanical tests conducted with frozen human skin and/or porcine skin as a human skin substitute. PMID:27558287

  2. A micromechanical comparison of human and porcine skin before and after preservation by freezing for medical device development

    NASA Astrophysics Data System (ADS)

    Ranamukhaarachchi, S. A.; Lehnert, S.; Ranamukhaarachchi, S. L.; Sprenger, L.; Schneider, T.; Mansoor, I.; Rai, K.; Häfeli, U. O.; Stoeber, B.

    2016-08-01

    Collecting human skin samples for medical research, including developing microneedle-based medical devices, is challenging and time-consuming. Researchers rely on human skin substitutes and skin preservation techniques, such as freezing, to overcome the lack of skin availability. Porcine skin is considered the best substitute to human skin, but their mechanical resemblance has not been fully validated. We provide a direct mechanical comparison between human and porcine skin samples using a conventional mechano-analytical technique (microindentation) and a medical application (microneedle insertion), at 35% and 100% relative humidity. Human and porcine skin samples were tested immediately after surgical excision from subjects, and after one freeze-thaw cycle at ‑80 °C to assess the impact of freezing on their mechanical properties. The mechanical properties of fresh human and porcine skin (especially of the stratum corneum) were found to be different for bulk measurements using microindentation; and both types of skin were mechanically affected by freezing. Localized in-plane mechanical properties of skin during microneedle insertion appeared to be more comparable between human and porcine skin samples than their bulk out-of-plane mechanical properties. The results from this study serve as a reference for future mechanical tests conducted with frozen human skin and/or porcine skin as a human skin substitute.

  3. Severe combined immunodeficiency mouse and human psoriatic skin chimeras. Validation of a new animal model.

    PubMed

    Nickoloff, B J; Kunkel, S L; Burdick, M; Strieter, R M

    1995-03-01

    Research into the cause and pathophysiological mechanisms underlying expression of psoriatric skin lesions has been hampered by lack of an appropriate animal model for this common and enigmatic cutaneous disease. These studies characterize normal skin, pre-psoriatic skin, and psoriatic plaque skin samples transplanted onto severe combined immunodeficiency mice. In this report we document that 1), normal, prepsoriatic, and psoriatic plaque keratome skin samples can be transplanted onto severe combined immunodeficiency mice reliably with high rates of graft survival (> 85%) and with reproducible changes consistently observed over prolonged periods of engraftment; 2), after transplantation, by clinical assessment and routine light microscopy, normal skin remained essentially normal whereas pre-psoriatic skin became thicker, and psoriatic plaque skin retained its characteristic plaque-type elevation and scale; 3), by using a panel of antibodies and immunohistochemical analysis, the overall phenotype of human cell types (including immunocytes) that persisted in the transplanted skin was remarkably similar to the immunophenotype of pretransplanted skin samples; 4), clearly recognized interface zones between human and murine skin within the epidermal and dermal compartments could be identified by routine microscopy and immunostaining, with focal areas of chimerism; and 5), elevated interleukin 8 cytokine levels were present in transplanted pre-psoriatic and psoriatic plaque skin samples. We conclude that there are many similarities between pre- and post-transplanted human samples of normal and psoriatic skin that are grafted onto severe combined immunodeficiency mice. Thus, we propose that this new animal model is appropriate for additional mechanistic-type studies designed to reveal the underlying genetic/etiological abnormality, as well as better illuminate the pathophysiological basis, for this important skin disease.

  4. Interaction of hydration, aging, and carbon content of soil on the evaporation and skin bioavailability of munition contaminants.

    PubMed

    Reifenrath, William G; Kammen, Harold O; Reddy, Gunda; Major, Michael A; Leach, Glenn J

    2008-01-01

    Water plays a key role in enhancing the permeability of human skin to many substances. To further understand its ability to potentially increase the bioavailability of soil contaminants, artificial sweat was applied to excised pig skin prior to dosing with munition-contaminated soils. Skin was mounted in chambers to allow simultaneous measurement of evaporation and penetration and to control air flow, which changed the dwell time of skin surface water within a l-h period post application of test materials. Additional variables included type of compound, aging of spiked soil samples, and carbon content of soil. To this end, the evaporation and skin penetration of C-14 labeled hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), 2,6-dinitrotoluene (26DNT), and 2,4,6-trinitrotoluene (TNT) were determined from two soil types, Yolo, having 1.2% carbon, and Tinker, having 9.5% carbon. RDX soil samples aged 27 mo and 62 mo were compared to freshly spiked soils samples. Similarly, 26DNT samples aged 35-36 mo and TNT samples aged 18 mo were compared to freshly spiked samples. Approximately 10 microg/cm(2) of radiolabeled compound was applied in 10 mg/cm(2) of soil. Radiolabel recovered from the dermis and tissue culture media (receptor fluid) was summed to determine percent absorption from the soils. Radiolabel recovered from vapor traps determined evaporation. Mean skin absorption of all compounds was higher for low-carbon soil, regardless of soil age and skin surface water as affected by air flow conditions. For 26DNT, a simultaneous increase in evaporation and penetration with conditions that favored enhanced soil hydration of freshly prepared samples was consistent with a mechanism that involved water displacement of 26DNT from its binding sites. A mean penetration of 17.5 +/- 3.6% was observed for 26DNT in low-carbon soil, which approached the value previously reported for acetone vehicle (24 +/- 6%). 26DNT penetration was reduced to 0.35% under dryer conditions and to 0

  5. Skin delivery of epigallocatechin-3-gallate (EGCG) and hyaluronic acid loaded nano-transfersomes for antioxidant and anti-aging effects in UV radiation induced skin damage.

    PubMed

    Avadhani, Kiran S; Manikkath, Jyothsna; Tiwari, Mradul; Chandrasekhar, Misra; Godavarthi, Ashok; Vidya, Shimoga M; Hariharapura, Raghu C; Kalthur, Guruprasad; Udupa, Nayanabhirama; Mutalik, Srinivas

    2017-11-01

    The present work attempts to develop and statistically optimize transfersomes containing EGCG and hyaluronic acid to synergize the UV radiation-protective ability of both compounds, along with imparting antioxidant and anti-aging effects. Transfersomes were prepared by thin film hydration technique, using soy phosphatidylcholine and sodium cholate, combined with high-pressure homogenization. They were characterized with respect to size, polydispersity index, zeta potential, morphology, entrapment efficiency, Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), X-ray Diffraction (XRD), in vitro antioxidant activity and ex vivo skin permeation studies. Cell viability, lipid peroxidation, intracellular ROS levels and expression of MMPs (2 and 9) were determined in human keratinocyte cell lines (HaCaT). The composition of the transfersomes was statistically optimized by Design of Experiments using Box-Behnken design with four factors at three levels. The optimized transfersome formulation showed vesicle size, polydispersity index and zeta potential of 101.2 ± 6.0 nm, 0.245 ± 0.069 and -44.8 ± 5.24 mV, respectively. FTIR and DSC showed no interaction between EGCG and the selected excipients. XRD results revealed no form conversion of EGCG in its transfersomal form. The optimized transfersomes were found to increase the cell viability and reduce the lipid peroxidation, intracellular ROS and expression of MMPs in HaCaT cells. The optimized transfersomal formulation of EGCG and HA exhibited considerably higher skin permeation and deposition of EGCG than that observed with plain EGCG. The results underline the potential application of the developed transfersomes in sunscreen cream/lotions for improvement of UV radiation-protection along with deriving antioxidant and anti-aging effects.

  6. Impact of AQP3 inducer treatment on cultured human keratinocytes, ex vivo human skin and volunteers.

    PubMed

    Garcia, N; Gondran, C; Menon, G; Mur, L; Oberto, G; Guerif, Y; Dal Farra, C; Domloge, N

    2011-10-01

    One of the main functions of the skin is to protect the organism against environmental threats, such as thermal stress. Aquaporin-3 (AQP3) facilitates water and glycerol transport across cell membranes and therefore regulates osmotic balance in different situations of stress. This mechanism seems to be particularly important for the resistance of different organisms to cold stress. Consequently, we were interested in investigating the effect of cold and osmotic stress on AQP3 expression in normal human keratinocytes. We developed a new active ingredient to stimulate aquaporins in skin and demonstrated the partial restoration of AQP3 expression in keratinocytes transfected with AQP3 siRNA. Moreover, we examined the effect of cold stress on cell morphology and the impact of a pre-treatment with the active ingredient. Our results indicated that induction of AQP3 helped maintain a correct organization of the actin cytoskeleton, preserving cell morphology and preventing cells from rounding. Immunofluorescent staining revealed cytoplasmic localization of AQP3 and its translocation to the cell membrane following osmotic stress. Histological ex vivo studies of skin under different conditions, such as cold environment and tape-stripping, indicated that increase in AQP3 expression appears to be involved in skin protection and showed that the pattern of AQP3 expression was more enhanced in the active ingredient-treated samples. In vivo confocal microscopy by Vivascope showed a generally healthier appearance of the skin in the treated areas. These results attest to the potential value of the active ingredient in optimizing environmental stress resistance and protecting the skin from stratum corneum damage.

  7. Human papillomaviruses and non-melanoma skin cancer.

    PubMed

    McLaughlin-Drubin, Margaret E

    2015-04-01

    Human papillomaviruses (HPVs) infect the squamous epithelium and can induce benign and malignant lesions. To date, more than 200 different HPV types have been identified and classified into five genera, α, β, γ, μ, and ν. While high-risk α mucosal HPVs have a well-established role in cervical carcinoma and a significant percentage of other anogenital tract and oral carcinomas, the biology of the cutaneous β HPVs and their contribution to non-melanoma skin cancer (NMSC) has been less studied. Although the association of β HPV infection with NMSC in patients with a rare, genetically determined condition, epidermodysplasia verruciformis has been well established, the role of β HPV infection with NMSC in the normal population remains controversial. In stark contrast to α HPV-associated cancers, the presence of the β HPV genome does not appear to be mandatory for the maintenance of the malignant phenotype. Moreover, the mechanism of action of the β HPV E6 and E7 oncoproteins differs from the β HPV oncoproteins.

  8. Tropical dermatology: Venomous arthropods and human skin: Part I. Insecta.

    PubMed

    Haddad, Vidal; Cardoso, João Luiz Costa; Lupi, Omar; Tyring, Stephen K

    2012-09-01

    Although many tropical insects carry infectious diseases, cutaneous injury can occur by other mechanisms, for example erucism (envenomation by caterpillars) or lepidopterism (dermatitis from moths). Pararama is a unique form of erucism seen in workers in contact with rubber trees in the Amazon, and it is caused by Premolis larvae, resulting in progressive periarticular fibrosis, ankylosis, and the loss of articulation. Ants and aquatic insects of the Belostomatidae family can cause painful bites and stings. Anaphylactic shock and death can result from the venom of bees and wasps. Beetles can cause vesicular dermatitis via cantharidin or paederin. Myiasis results from fly larvae (maggots) feeding on live or necrotic tissue of humans or other hosts, while New World screwworm fly larvae feed only on living tissue and burrow (ie, screw) more deeply when attempts are made to remove them. Tungiasis is characterized by very pruritic and painful papules and ulcers resulting from a Tunga flea penetrating the host's skin. Dermatologists should be able to diagnose and treat the cutaneous manifestations of these tropical insects and educate their patients on prevention.

  9. Color enhancement in multispectral image of human skin

    NASA Astrophysics Data System (ADS)

    Mitsui, Masanori; Murakami, Yuri; Obi, Takashi; Yamaguchi, Masahiro; Ohyama, Nagaaki

    2003-07-01

    Multispectral imaging is receiving attention in medical color imaging, as high-fidelity color information can be acquired by the multispectral image capturing. On the other hand, as color enhancement in medical color image is effective for distinguishing lesion from normal part, we apply a new technique for color enhancement using multispectral image to enhance the features contained in a certain spectral band, without changing the average color distribution of original image. In this method, to keep the average color distribution, KL transform is applied to spectral data, and only high-order KL coefficients are amplified in the enhancement. Multispectral images of human skin of bruised arm are captured by 16-band multispectral camera, and the proposed color enhancement is applied. The resultant images are compared with the color images reproduced assuming CIE D65 illuminant (obtained by natural color reproduction technique). As a result, the proposed technique successfully visualizes unclear bruised lesions, which are almost invisible in natural color images. The proposed technique will provide support tool for the diagnosis in dermatology, visual examination in internal medicine, nursing care for preventing bedsore, and so on.

  10. Combinatorial Color Space Models for Skin Detection in Sub-continental Human Images

    NASA Astrophysics Data System (ADS)

    Khaled, Shah Mostafa; Saiful Islam, Md.; Rabbani, Md. Golam; Tabassum, Mirza Rehenuma; Gias, Alim Ul; Kamal, Md. Mostafa; Muctadir, Hossain Muhammad; Shakir, Asif Khan; Imran, Asif; Islam, Saiful

    Among different color models HSV, HLS, YIQ, YCbCr, YUV, etc. have been most popular for skin detection. Most of the research done in the field of skin detection has been trained and tested on human images of African, Mongolian and Anglo-Saxon ethnic origins, skin colors of Indian sub-continentals have not been focused separately. Combinatorial algorithms, without affecting asymptotic complexity can be developed using the skin detection concepts of these color models for boosting detection performance. In this paper a comparative study of different combinatorial skin detection algorithms have been made. For training and testing 200 images (skin and non skin) containing pictures of sub-continental male and females have been used to measure the performance of the combinatorial approaches, and considerable development in success rate with True Positive of 99.5% and True Negative of 93.3% have been observed.

  11. Human Split-Thickness Skin Allograft from Brain-Dead Donors

    PubMed Central

    Khodadadi, A.; Olang, O; Makhllough, A; Nozary Heshmati, B.; Azmoudeh Ardalan, F.; Tavakoli, S. A.

    2016-01-01

    Background: Looking for an appropriate skin substitute for temporary and permanent coverage of wounds remains one of the main obstacles of medical researchers. Objective: To investigate the rate of inflammation, symbiosis, and survival of grafted allograft skin from brain-dead donors (BDDs) in rabbits. Methods: After receiving negative serologic tests of BDDs, we prepared partial thickness skin grafts. They were then used in treating wounds of 5 rabbits in comparison with split-thickness skins taken from cardiac dead donors. Results: On histopathological examinations, we found no difference between the skins. All samples were separated from the baseline in 15–20 days. Conclusion: Gamma-irradiated freeze-dried human split-thickness skin taken from BDDs is safe and can be used for the treatment of deep skin burns. PMID:27721966

  12. Biomechanical properties of in vivo human skin from dynamic optical coherence elastography.

    PubMed

    Liang, Xing; Boppart, Stephen A

    2010-04-01

    Dynamic optical coherence elastography is used to determine in vivo skin biomechanical properties based on mechanical surface wave propagation. Quantitative Young's moduli are measured on human skin from different sites, orientations, and frequencies. Skin thicknesses, including measurements from different layers, are also measured simultaneously. Experimental results show significant differences among measurements from different skin sites, between directions parallel and orthogonal to Langer's lines, and under different skin hydration states. Results also suggest surface waves with different driving frequencies represent skin biomechanical properties from different layers in depth. With features such as micrometer-scale resolution, noninvasive imaging, and real-time processing from the optical coherence tomography technology, this optical measurement technique has great potential for measuring skin biomechanical properties in dermatology.

  13. Multivariate Models for Prediction of Human Skin Sensitization Hazard

    EPA Science Inventory

    One of ICCVAM’s top priorities is the development and evaluation of non-animal approaches to identify potential skin sensitizers. The complexity of biological events necessary for a substance to elicit a skin sensitization reaction suggests that no single alternative method...

  14. Multivariate Models for Prediction of Skin Sensitization Hazard in Humans

    EPA Science Inventory

    One of ICCVAM’s highest priorities is the development and evaluation of non-animal approaches to identify potential skin sensitizers. The complexity of biological events necessary for a substance to elicit a skin sensitization reaction suggests that no single alternative me...

  15. Machine Learning Approaches for Predicting Human Skin Sensitization Hazard

    EPA Science Inventory

    One of ICCVAM’s top priorities is the development and evaluation of non-animal approaches to identify potential skin sensitizers. The complexity of biological events necessary for a substance to elicit a skin sensitization reaction suggests that no single in chemico, in vit...

  16. Accelerated aging syndromes, are they relevant to normal human aging?

    PubMed

    Dreesen, Oliver; Stewart, Colin L

    2011-09-01

    Hutchinson-Gilford Progeria (HGPS) and Werner syndromes are diseases that clinically resemble some aspects of accelerated aging. HGPS is caused by mutations in theLMNA gene resulting in post-translational processing defects that trigger Progeria in children. Werner syndrome, arising from mutations in the WRN helicase gene, causes premature aging in young adults. What are the molecular mechanism(s) underlying these disorders and what aspects of the diseases resemble physiological human aging? Much of what we know stems from the study of patient derived fibroblasts with both mutations resulting in increased DNA damage, primarily at telomeres. However, in vivo patients with Werner's develop arteriosclerosis, among other pathologies. In HGPS patients, including iPS derived cells from HGPS patients, as well as some mouse models for Progeria, vascular smooth muscle (VSM) appears to be among the most severely affected tissues. Defective Lamin processing, associated with DNA damage, is present in VSM from old individuals, indicating processing defects may be a factor in normal aging. Whether persistent DNA damage, particularly at telomeres, is the root cause for these pathologies remains to be established, since not all progeroid Lmna mutations result in DNA damage and genome instability.

  17. DNA methylation and healthy human aging.

    PubMed

    Jones, Meaghan J; Goodman, Sarah J; Kobor, Michael S

    2015-12-01

    The process of aging results in a host of changes at the cellular and molecular levels, which include senescence, telomere shortening, and changes in gene expression. Epigenetic patterns also change over the lifespan, suggesting that epigenetic changes may constitute an important component of the aging process. The epigenetic mark that has been most highly studied is DNA methylation, the presence of methyl groups at CpG dinucleotides. These dinucleotides are often located near gene promoters and associate with gene expression levels. Early studies indicated that global levels of DNA methylation increase over the first few years of life and then decrease beginning in late adulthood. Recently, with the advent of microarray and next-generation sequencing technologies, increases in variability of DNA methylation with age have been observed, and a number of site-specific patterns have been identified. It has also been shown that certain CpG sites are highly associated with age, to the extent that prediction models using a small number of these sites can accurately predict the chronological age of the donor. Together, these observations point to the existence of two phenomena that both contribute to age-related DNA methylation changes: epigenetic drift and the epigenetic clock. In this review, we focus on healthy human aging throughout the lifetime and discuss the dynamics of DNA methylation as well as how interactions between the genome, environment, and the epigenome influence aging rates. We also discuss the impact of determining 'epigenetic age' for human health and outline some important caveats to existing and future studies.

  18. Aging-associated changes in human brain.

    PubMed

    Mrak, R E; Griffin, S T; Graham, D I

    1997-12-01

    A wide variety of anatomic and histological alterations are common in brains of aged individuals. However, identification of intrinsic aging changes--as distinct from changes resulting from cumulative environmental insult--is problematic. Some degree of neuronal and volume loss would appear to be inevitable, but recent studies have suggested that the magnitudes of such changes are much less than previously thought, and studies of dendritic complexity in cognitively intact individuals suggest continuing neuronal plasticity into the eighth decade. A number of vascular changes become more frequent with age, many attributable to systemic conditions such as hypertension and atherosclerosis. Age-associated vascular changes not clearly linked to such conditions include hyaline arteriosclerotic changes with formation of arterial tortuosities in small intracranial vessels and the radiographic changes in deep cerebral white matter known as "leukoaraiosis." Aging is accompanied by increases in glial cell activation, in oxidative damage to proteins and lipids, in irreversible protein glycation, and in damage to DNA, and such changes may underlie in part the age-associated increasing incidence of "degenerative" conditions such as Alzheimer disease and Parkinson disease. A small number of histological changes appear to be universal in aged human brains. These include increasing numbers of corpora amylacea within astrocytic processes near blood-brain or cerebrospinal fluid-brain interfaces, accumulation of the "aging" pigment lipofuscin in all brain regions, and appearance of Alzheimer-type neurofibrillary tangles (but not necessarily amyloid plaques) in mesial temporal structures.

  19. Obesity accelerates epigenetic aging of human liver.

    PubMed

    Horvath, Steve; Erhart, Wiebke; Brosch, Mario; Ammerpohl, Ole; von Schönfels, Witigo; Ahrens, Markus; Heits, Nils; Bell, Jordana T; Tsai, Pei-Chien; Spector, Tim D; Deloukas, Panos; Siebert, Reiner; Sipos, Bence; Becker, Thomas; Röcken, Christoph; Schafmayer, Clemens; Hampe, Jochen

    2014-10-28

    Because of the dearth of biomarkers of aging, it has been difficult to test the hypothesis that obesity increases tissue age. Here we use a novel epigenetic biomarker of aging (referred to as an "epigenetic clock") to study the relationship between high body mass index (BMI) and the DNA methylation ages of human blood, liver, muscle, and adipose tissue. A significant correlation between BMI and epigenetic age acceleration could only be observed for liver (r = 0.42, P = 6.8 × 10(-4) in dataset 1 and r = 0.42, P = 1.2 × 10(-4) in dataset 2). On average, epigenetic age increased by 3.3 y for each 10 BMI units. The detected age acceleration in liver is not associated with the Nonalcoholic Fatty Liver Disease Activity Score or any of its component traits after adjustment for BMI. The 279 genes that are underexpressed in older liver samples are highly enriched (1.2 × 10(-9)) with nuclear mitochondrial genes that play a role in oxidative phosphorylation and electron transport. The epigenetic age acceleration, which is not reversible in the short term after rapid weight loss induced by bariatric surgery, may play a role in liver-related comorbidities of obesity, such as insulin resistance and liver cancer.

  20. A robust sebum, oil, and particulate pollution model for assessing cleansing efficacy of human skin.

    PubMed

    Peterson, G; Rapaka, S; Koski, N; Kearney, M; Ortblad, K; Tadlock, L

    2016-10-31

    With increasing concerns over the rise of atmospheric particulate pollution globally and its impact on systemic health and skin ageing, we have developed a pollution model to mimic particulate matter trapped in sebum and oils creating a robust (difficult to remove) surrogate for dirty, polluted skin.

  1. Impairments in central cardiovascular function contribute to attenuated reflex vasodilation in aged skin.

    PubMed

    Greaney, Jody L; Stanhewicz, Anna E; Proctor, David N; Alexander, Lacy M; Kenney, W Larry

    2015-12-15

    During supine passive heating, increases in skin blood flow (SkBF) and cardiac output (Qc) are both blunted in older adults. The aim here was to determine the effect of acutely correcting the peripheral vasodilatory capacity of aged skin on the integrated cardiovascular responses to passive heating. A secondary aim was to examine the SkBF-Qc relation during hyperthermia in the presence (upright posture) and absence (dynamic exercise) of challenges to central venous pressure. We hypothesized that greater increases in SkBF would be accompanied by greater increases in Qc. Eleven healthy older adults (69 ± 3 yr) underwent supine passive heating (0.8°C rise in core temperature; water-perfused suit) after ingesting sapropterin (BH4, a nitric oxide synthase cofactor; 10 mg/kg) or placebo (randomized double-blind crossover design). Twelve young (24 ± 1 yr) subjects served as a comparison group. SkBF (laser-Doppler flowmetry) and Qc (open-circuit acetylene wash-in) were measured during supine heating, heating + upright posture, and heating + dynamic exercise. Throughout supine and upright heating, sapropterin fully restored the SkBF response of older adults to that of young adults but Qc remained blunted. During heat + upright posture, SkBF failed to decrease in untreated older subjects. There were no age- or treatment-related differences in SkBF-Qc during dynamic exercise. The principal finding of this study was that the blunted Qc response to passive heat stress is directly related to age as opposed to the blunted peripheral vasodilatory capacity of aged skin. Furthermore, peripheral impairments to SkBF in the aged may contribute to inapposite responses during challenges to central venous pressure during hyperthermia.

  2. In vivo non-invasive multiphoton tomography of human skin

    NASA Astrophysics Data System (ADS)

    König, Karsten; Riemann, Iris; Ehlers, Alexander; Le Harzic, Ronan

    2005-10-01

    High resolution non-invasive 3D imaging devices are required to detect pathogenic microorganisms such as Anthrax spores, bacteria, viruses, fungi and chemical agents entering biological tissues such as the epidermis. Due to the low light penetration depth and the biodamage potential, ultraviolet light sources can not be employed to realize intratissue imaging of bio- and chemohazards. We report on the novel near infrared laser technology multiphoton tomography and the high resolution 4D imaging tool DermaInspect for non-invasive detection of intratissue agents and their influence on cellular metabolism based on multiphoton autofluorescence imaging (MAI) and second harmonic generation (SHG). Femtosecond laser pulses in the spectral range of 750 nm to 850 nm have been used to image in vivo human skin with subcellular spatial and picosecond temporal resolution. The non-linear induced autofluorescence of both, skin tissues and microorganisms, originates mainly from naturally endogenous fluorophores/protein structures like NAD(P)H, flavins, keratin, collagen, elastin, porphyrins and melanin. Bacteria emit in the blue/green spectral range due to NAD(P)H and flavoproteins and, in certain cases, in the red spectral range due to the biosynthesis of Zn-porphyrins, coproporphyrin and protoporphyrin. Collagen and exogenous non-centrosymmetric molecules can be detected by SHG signals. The system DermaInspect consists of a wavelength-tunable compact 80/90 MHz Ti:sapphire laser, a scan module with galvo scan mirrors, piezo-driven objective, fast photon detector and time-resolved single photon counting unit. It can be used to perform optical sectioning and 3D autofluorescence lifetime imaging (τ-mapping) with 1 μm spatial resolution and 270 ps temporal resolution. The parameter fluorescence lifetime depends on the type of fluorophore and its microenvironment and can be used to distinguish bio- and chemohazards from cellular background and to gain information for pathogen

  3. Triple nanoemulsion potentiates the effects of topical treatments with microencapsulated retinol and modulates biological pro