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Scavenger receptor B1 (SR-B1) is a transmembrane protein, involved in tissue reverse cholesterol transport and known as HDLs main receptor. Several studies have demonstrated that SR-B1 is also implicated in several other processes, such as bacteria and apoptotic cells recognition and regulation of intracellular antioxidant levels. Although this receptor is mainly localized in the liver and steroidogenic tissues, it has been shown that it is significantly expressed also in human skin, especially in the epidermis.
There is increasing evidence that cutaneous ischemia-reperfusion (I/R) injury is associated with the development of pressure ulcers (PUs). Botulinum toxin (BTX) suppress the release of neurotransmitters such as acetylcholine in the neuromuscular junction. Several studies have demonstrated that BTX enhanced the blood flow and survival of ischemic skin flaps in animal cutaneous flap models. The objective of this study is to assess the effects of BTX-B on the formation of PUs in the cutaneous I/R injury.
Human skin was the first tissue application to be successfully engineered in vitro by combining advanced cell culture techniques and various scaffolding biomaterials to support cell growth and 3D organization. Current skin tissue engineering technologies often only include the epidermal components and remain partially effective in their ability to restore the complexity of the dermal compartment. To date, none of these approaches regenerate skin appendages including sebaceous glands, which are responsible for the sebum production, essential to maintain the integrity of the skin barrier.
Recently, based on a comparative study of nail and hair we demonstrated the presence of nail matrix onychodermis containing onychofibroblasts by CD13 expression. In this study, we further investigated about the nail matrix onychodermis through ECM immunohistochemistry. We performed immunohistochemistry for collagen and elastin on polydactyly nail units, and on hair follicles in scalp specimens. Collagen and elastin were rarely expressed in the mesenchyme containing onychofibroblasts below the nail matrix while it was expressed strongly in the dermis of other parts of the nail unit.
Humans differ in many respects from other primates, but perhaps no derived human feature is more striking than our naked skin. Long purported to be adaptive, humans’ unique external appearance is characterized by changes in both the patterning of hair follicles and eccrine sweat glands, producing decreased hair cover and increased sweat gland density. Despite the conspicuousness of these features and their potential evolutionary importance, there is a lack of clarity regarding how they evolved within the primate lineage.
Transient receptor potential vanilloid type 1 (TRPV1) is a nonselective cationic channel that was originally described on nociceptive neurons as a major sensor of noxious stimuli such as heat and low pH. Subsequently, TRPV1 has been described in plethora of non-neuronal tissues and cells including epidermal keratinocytes. More recent studies have expanded the role of TRPV1 in human skin beyond nociception by showing that TRPV1 activation reduces keratinocyte proliferation and delays epidermal barrier recovery.
Background: Ambient particulate matter (PM) represents an environmental threat to which millions of people worldwide are exposed. Adverse effects of PM on human health have been reported, but its effect on skin aging has not been widely studied. Autophagy is a regulatory “self-eating” process and is one of the survival mechanisms for cells during extrinsic and intrinsic stress. Objectives: In this study, we aimed to examine the relationship between PM exposure, autophagy and skin aging. Methods: We compared the levels of autophagy in human skin fibroblasts before and after PM exposure.
Multilineage-differentiating stress enduring (Muse) cells are pluripotent stem cells that exist in human mesenchymal tissues such as dermis, adipose tissue and bone marrow. We have reported that human Muse cells isolated from dermal fibroblasts and adipose tissues can differentiate into keratinocytes, fibroblasts and melanocytes to reconstitute 3-dimentional skin (JDS 2017 and JID 2017). In anticipation of clinical application and transport of Muse cells among facilities for future use, we now seek the methodology to store Muse cells.
Confocal and multiphoton microscopies have emerged as useful tools for the non-invasive visualization of normal and pathological skin with high resolution. However, these techniques are characterized by a limited penetration depth due to light scattering and can cause photobleaching. Light-sheet fluorescence microscopy (LSFM) is an attractive approach that has shown promise for acquisition of volumetric data of thick tissues. In this study, LSFM was combined with optical clearing methods to allow in-depth optical sectioning of entire human skin biopsies and generate 3D images.
Polyunsaturated fatty acids (PUFAs) are longchain fatty acids contain two or more double bonds along their carbon backbones. Arachidonic acid (AA) and eicosapentaenoic acid (EPA) are omega-6 and omega-3 fatty acid each and exert their effects through changes in membrane phospholipids or the production of signaling molecules such as eicosanoids. AA and EPA, its eicosanoid metabolites are involved in the regulation of many cellular processes, such as cell survival, angiogenesis, chemotaxis, mitogenesis, apoptosis and migration.
The skin epidermis has a stereotypical developmental and stratification program with specific cell division paradigms that may dictate progenitor cell fate. Centrosomes, the major microtubule organizing centers of animal cells, organize mitotic spindle microtubules and regulate cell division. During interphase and in differentiated cells, centrosomes provide the essential template for cilia. The functions of centrosomes during epidermal development have not been defined. In order to genetically determine and delineate the functions of mammalian centrosomes and cilia, we have conditionally removed Sas-4, which is essential for centrosome formation, or Ift88, which is essential for cilia but not centrosome formation, in the developing mouse skin epithelium.
Purpose: Organ transplant patients are required to take lifelong immunosuppressant medications, resulting in a higher risk of developing skin cancer. Although skin of color will make up an estimated 50% of the population by 2050, very little is known about the risk of developing skin cancer in transplant patients with skin of color. This study explored racial differences in skin cancer outcomes, including the number of skin cancers, spread of cancer to other organs, and death from skin cancer. Methods: This chart review studied three types of skin cancer (basal cell, squamous cell, and melanoma skin cancer) in a group of individuals who are both non-white and have received organ transplants.
Dermatomyositis-related panniculitis (DP) manifests as red subcutaneous, firm and tender plaques, usually on the arms, buttocks, thighs and abdomen. DP is commonly described in textbooks yet there are few reports in the medical literature and there are no guidelines on its best management. Here we present a case of a patient with DP of the neck region. Case Description: A 66-year-old African American woman with a three-year history of dermatomyositis with high titer antinuclear antibody, characteristic pattern of rash, and muscle weakness presented with progressive neck swelling, neck pain, dysphagia, and dyspnea over a period of two months.
Objective: Melanosome (MS) is an acidic organelle enveloped by the monolayer plasma membrane. The intraluminal pH of melanosomes is approximately 4-5. However, the optimal pH for tyrosinase has been shown at 6.8. Modulation of intraluminal pH in melanosomes seems to be helpful to screen reversible skin-lightening agents. Vitamine C (L-ascorbic acid) has been clinically proven to be effective in the treatment of melasma, but the mechanism underlying skin-lightening remains undefined. In this study, we investigated whether VC and its two derivatives, magnesium ascorbyl phosphate (MAP) and 3-o-ethyl-L-ascorbic acid (VCE), could acidify melamosomes and inhibit melanogenesis.
Vitiligo is a common depigmentation disease characterized by the lack of viable melanocytes in the lesional skin. However, the full extent of cellular and molecular defects in vitiligo affected skin has not been clearly understood. The purpose of this study is to systematically characterize the molecular changes between lesional and nonlesional skin of vitiligo using normal healthy skin as the reference. Transcriptome sequencing was performed on messenger RNAs isolated from 110 skin biopsies (vitiligo lesional, vitiligo non-lesional, chronic dermatitis lesional, and healthy skin).
Rapid growth of malignant melanoma is associated with aggressive histopathologic features, and poor prognosis in cutaneous melanoma. However, the impact of the growth rate (GR) on lymph node (LN) metastasis and survival in acral melanoma (AM) has not been investigated. We conducted this study to identify the influence of GR on LN metastasis and survival in AM. We analyzed data of invasive AM patients who underwent surgery at our institution over a period of 20 years. GR was calculated as the ratio of Breslow thickness to delay to operation from disease onset.
Palmitoyl-KVK-L-ascorbic acid (Duo-vitapep) is the whitening agent synthesized by conjugation of palmitoyl-KVK and ascorbic acid. In a previous study, we demonstrated the skin-whitening effect in clinical trial and the reduction of melanin contents in B16F1 cells. However, the underlying mechanism involved in melanogenesis has not elucidated yet. In this study, we investigated the expression of enzymes and their cellular signaling pathways involved in melanin synthesis. Treatment of B16F1 cells with Duo-vitapep reduced cellular tyrosinase activity but did not inhibit cell-free tyrosinase activity.
Vitiligo is characterized by loss of functional epidermal melanocytes. Even if, several factors have been recognized as possible determinants of the disease, oxidative stress has been demonstrated as an important pathogenic mechanism. Increased cellular vulnerability to oxidative insults associated with modifications in the expression senescence markers have been highlighted in melanocytes, fibroblast and keratinocytes demonstrating that oxidative damage is not restricted to the melanocyte lineage.
Vitiligo is an acquired skin disorder characterized by the loss of pigment cells from the epidermis. We found there were abundant SENP proteins couple with the abnormal chemokines in vitiligo lesions. SUMOylation is a reversible process that is catalyzed by the enzymes and reversed by a family of Sentrin/SUMO-specific proteases(SENPs). Interferon-γ (IFN-γ) triggers keratinocytes for inflammation response by activating the intracellular JAK−STAT1 signaling. By analyzing the expression profiles of genes from SENP1-/- cells, we found the down-regulation of IFN target genes in SENP-/-cell in comparison with SENP+/+.
A growing amount of evidence argues for intrinsic metabolic defects in vitiligo melanocytes, leading to an intracellular oxidative stress that may act as the main intracellular signal transduction sustaining cell degeneration. We recently demonstrated that cellular and functional alterations are not restricted to melanocytes but are extended to dermal fibroblasts, indicating the existence of altered cross-talk between dermal and epidermal components. Autophagy is a self-digestion process, which is activated as a catabolic mechanism against oxidative stress.