Experimental dermatology
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Experimental dermatology · Apr 2018
ReviewSystemic immune mechanisms in atopic dermatitis and psoriasis with implications for treatment.
Atopic dermatitis (AD) and psoriasis are inflammatory skin diseases that negatively affect patients' quality of life. Although distinctions exist between these diseases, both are characterized by erythematous, thickened epidermal lesions that vary in intensity and affected body surface area. Early models of aetiology attributed symptoms of both diseases to cutaneous inflammation at lesion sites, but recent studies have established that activated immune mediators in the circulation drive disease severity. ⋯ Patients with both disorders are at significantly higher risk of obesity, metabolic disorders, and cardiovascular diseases, all of which feature inflammatory components in their pathology models. These insights have led to novel therapeutics aimed at addressing psoriasis by targeting tumor necrosis factor- and Th17-related cytokine pathways. The success of these agents in psoriasis management is driving new therapeutic approaches for moderate-to-severe AD, including agents targeting the Th2 and Th17/Th22 cytokine pathways.
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Experimental dermatology · Mar 2018
Comprehensive circRNA expression profile and construction of circRNA-associated ceRNA network in fur skin.
Circular RNA (circRNA), a class of non-coding RNAs, is a new group of RNAs that are related to tumorigenesis. The role of circRNAs in various diseases has been already highlighted. However, the expression levels and functions of circRNAs related to the melanocytes in the skin are poorly understood. ⋯ Results showed that the specific mRNAs mainly involved in the transcription-related GOs, especially GO:0042802, GO:0005080 and GO:0032403, demonstrate their specific actions in transcriptional regulation. In the circRNA-miRNA-mRNA network, the most enriched GO terms of the mRNAs were pigmentation, protein autophosphorylation and protein complex. Therefore, the circRNA-miRNA-mRNA pathway may reveal novel mechanisms for pigmentation, and circRNAs may serve as candidates in pigmentation.
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Experimental dermatology · Jul 2017
LetterDigital imaging biomarkers feed machine learning for melanoma screening.
We developed an automated approach for generating quantitative image analysis metrics (imaging biomarkers) that are then analysed with a set of 13 machine learning algorithms to generate an overall risk score that is called a Q-score. These methods were applied to a set of 120 "difficult" dermoscopy images of dysplastic nevi and melanomas that were subsequently excised/classified. This approach yielded 98% sensitivity and 36% specificity for melanoma detection, approaching sensitivity/specificity of expert lesion evaluation. Importantly, we found strong spectral dependence of many imaging biomarkers in blue or red colour channels, suggesting the need to optimize spectral evaluation of pigmented lesions.
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Experimental dermatology · Dec 2016
Light-emitting diodes downregulate cathelicidin, kallikrein and toll-like receptor 2 expressions in keratinocytes and rosacea-like mouse skin.
Cathelicidin (LL-37), Toll-like receptor 2 (TLR-2) and kallikreins (KLKs) are key inflammatory mediators in rosacea. Laser or light-based devices have been successfully used for rosacea. We investigated the effects of light-emitting diodes (LEDs) on LL-37, KLKs, TLR-2 and protease activity in cultured normal human epidermal keratinocytes (NHEKs) and rosacea-like mouse skin (RLMS). ⋯ LED at 630 and 940 nm downregulated TLR-2, KLK5 and LL-37 expressions and protease activity in NHEK and RLMS. Thus, LEDs may be promising for rosacea treatment. However, clinical trials are required for further study.
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Experimental dermatology · Oct 2015
Sesamol decreases melanin biosynthesis in melanocyte cells and zebrafish: Possible involvement of MITF via the intracellular cAMP and p38/JNK signalling pathways.
The development of antimelanogenic agents is important for the prevention of serious aesthetic problems such as melasma, freckles, age spots and chloasma. The aim of this study was to investigate the antimelanogenic effect of sesamol, an active lignan isolated from Sesamum indicum, in melan-a cells. Sesamol strongly inhibited melanin biosynthesis and the activity of intracellular tyrosinase by decreasing cyclic adenosine monophosphate (cAMP) accumulation. ⋯ Moreover, sesamol dose-dependently decreased zebrafish pigment formation, tyrosinase activity and expression of melanogenesis-related genes. These findings indicate that sesamol inhibited melanin biosynthesis by down-regulating tyrosinase activity and melanin production via regulation of gene expression of melanogenesis-related proteins through modulation of MITF activity, which promoted phosphorylation of p38 and JNK in melan-a cells. Together, these results suggest that sesamol strongly inhibits melanin biosynthesis, and therefore, sesamol represents a new skin-whitening agent for use in cosmetics.