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In this study, we determined the effects of benzo(a)pyrene (BaP) on the expression of aryl hydrocarbon receptor (AhR) and cytochrome P450 1A1 (CYP1A1), and assessed the action of BaP on inflammatory cytokine expression and lipid synthesis in SZ95 sebocytes in vitro . BaP (10 −8 , 10 −7 , 10 −6 and 10 −5 M) was not cytotoxic for SZ95 sebocytes after 24 h exposure. Expression of AhR was promoted in mRNA lever, while was inhibited in protein lever after BaP (10 −5 M) exposure. CYP1A1 expression was up-regulated in both mRNA and protein levels. BaP (10 −5 M) exerted a stimulatory action on interleukin (IL)-6 secretion, while a dose-dependently inhibitory effect on lipid synthesis from 10 −8 M to 10 −5 M in SZ95 sebocytes. Both actions were partly antagonized in AhR-knockdowned SZ95 sebocytes. This study demonstrates that BaP can activate AhR signaling pathway, and exhibits pro-inflammatory effects and inhibitory effects on sebum production in human sebocytes. [ABSTRACT FROM AUTHOR]

• Resveratrol inhibit lipogenesis and inflammation in human sebocytes in vitro. • Resveratrol could activate AMPK signaling in human sebocytes in vitro. • Resveratrol treats acne by inhibiting lipogenesis and inflammation via AMPK pathway. Acne vulgaris is a prevalent skin disease lacking effective and well-tolerated treatment. An earlier study indicated that resveratrol (RVT) has therapeutic effects in acne patients through unknown mechanisms. To evaluate the effects of RVT on linoleic acid (LA)-induced lipogenesis and peptidoglycan (PGN)-induced inflammation in cultured SZ95 sebocytes in vitro , and to investigate the underlying mechanisms. RNA-sequencing was used to analyze the whole transcriptome. Nile red staining was used to detect intracellular neutral lipids, whereas lipidomics was used to investigate changes in the lipid profile in sebocytes. Interleukin (IL)-1β and IL-6 mRNA and protein levels were assessed through quantitative real-time PCR and Enzyme-linked immunosorbent assay, respectively. Western blot was used to evaluate the expression of lipogenesis-related proteins, the inflammatory signaling pathway, and the AMP-activated protein kinase (AMPK) pathway. Further, specific small interfering RNA (siRNA) was used to knockdown sirtuin-1 (SIRT1) expression. RVT inhibited the lipogenesis-related pathway and nuclear factor-kappa B (NF-κB) signaling pathway in SZ95 sebocytes. It also downregulated LA-induced lipogenesis, the expression of lipid-related proteins, and the contents of unsaturated fatty acids. Besides, RVT promoted SIRT1 expression and deacetylation of the NF-κB p65 subunit, thereby lowering IL-1β and IL-6 secretion under PGN induction. Furthermore, pretreatment with AMPK inhibitor Compound C abolished RVT-mediated sebosuppressive and anti-inflammation effects. Meanwhile, SIRT1 silencing abrogated the anti-inflammatory potential of RVT. In human SZ95 sebocytes, RVT exhibits sebosuppressive and anti-inflammatory effects partially through the AMPK pathway, which may justify the role of RVT treatment in acne vulgaris. [ABSTRACT FROM AUTHOR]

Phototherapy is an effective therapeutic option in the treatment of vitiligo; however, responses varied among the different types. The underlying mechanism has scarcely been investigated. To investigate and compare the effects of phototherapy on the mutation of melanocyte lineage differentiated from human scalp-derived neural crest stem cells (HS-NCSCs) with p75 neurotrophin receptor expression positive and p75 neurotrophin receptor expression negative group in vitro, the HS-NCSCs were isolated from fetal scalp tissue, which is identified by immunofluorescent staining. The p75(+) and p75(−) cells from HS-NCSCs were isolated by magnetic cell sorting, respectively. The embryonic neural crest stem cell biomarkers were detected by RT-PCR. Narrow-band UVB (NB-UVB) was used to irradiate the cells. Cell proliferation was evaluated by cell count. Tyrosinase, Tyrp1, and Tyrp2 gene expression were measured by quantitative RT-PCR. Tyrosinase and GRCR protein levels were investigated by Western blot analysis. The electrophoretic strip showed that Sox2, Oct4, Sox10, and Nestin of p75(+) HS-NCSCs were brighter than the p75(−) HS-NCSCs. After the same dose radiation with NB-UVB, the cell proliferation of p75(+) group showed less inhibitory rate compared with the p75(−) HS-NCSCs. The tyrosinase mRNA and protein expression of differentiated melanocytes increased significantly in the group of p75(+) HS-NCSCs compared with the p75(−) group. The melanocytic mutation of p75(+) HS-NCSCs increased significantly compared with the p75(−) HS-NCSCs under NB-UVB, which indicated there were more melanocyte precursors in the differentiated cells from p75(+) HS-NCSCs. This may provide new insights for the different repigmentation efficacy of segmental and non-segmental vitiligo. [ABSTRACT FROM AUTHOR]

Objective: This study was designed to study the clinical and histopathological characteristics of patients with the scarring folliculitis type acne inversa in Chinese population. Methods: A total of 21 patients with acne inversa and 6 controls without known dermatological disease were recruited from outpatient department of dermatology and orthopedic surgery. Two-millimeter punch biopsies were taken from 8 patients with acne inversa and 6 controls, fixed in formalin, embedded in paraffin and stained with haematoxylin and eosin prior to histopathological analysis. Results: There were 12 patients (57.14%) belonging to the scarring folliculitis type presented with double comedones, papules, nodules, depressed scars, and were mainly Hurley stage I (66.67%). Many of the scarring folliculitis type were smokers (58.33%), some had a history of occupational exposure (41.67%) and some were overweight (50%), the mean BMI of which is 25.18±3.16 kg/m2. Histopathological changes such as perifollicular inflammation can be observed in scarring folliculitis type of acne inversa and controls as well. However, epidermal hyperplasia, follicular hyperplasia, sebaceous gland disappearance, destruction of hair follicle and sebaceous gland, collagen hyperplasia, perivascular inflammation, granulomatous inflammation, Micro thrombus were only seen in scarring folliculitis type. The mean surface area in patients (8073.36±15798.43 μm2) was smaller than that in controls (302059.08±502813.78 μm2), with statistically significant difference. (P = 0.024). Conclusion: The scarring folliculitis type in acne inversa in Chinese population could be characterized by depressed scars, double-ended comedones, epidermal cysts and had high proportion of smokers, or occupational exposure with lower Hurley stage, as well as diminished sebaceous gland. Further studies are needed to clarify the relations between the clinical subtypes of acne inversa and their corresponding genetypes. [ABSTRACT FROM AUTHOR]

The aryl hydrocarbon receptor (AhR) is the receptor for 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), benzo(a)pyrene (BaP) and other exogenous compounds. In human sebocytes, TCDD and BaP were found to activate the expression of multiple genes, including cytochrome P450 1A1 (CYP1A1), and inhibit lipid synthesis via AhR, while little is known about endogenous functions of the AhR. In order to expand this knowledge, we analyzed the impact of AhR knockdown on lipid synthesis as well as on cell differentiation of SZ95 sebocytes in vitro and observed that lipid synthesis was significantly induced in AhR silenced SZ95 sebocytes. In line with this result, expression of lipogenesis-associated genes, such as peroxisome proliferator activated receptor (PPAR) δ and PPARγ, was increased. Morphological changes with smaller cells in size but more abundant cytoplasmic lipids were observed in AhR silenced SZ95 sebocytes compared with the AhR activated cells. Besides, the expression of keratin 7, an early sebaceous differentiation marker, was increased, while the expression of the terminal sebocyte differentiation marker epithelial membrane antigen (EMA) was reduced. Moreover, the terminal keratinocyte differentiation markers keratin 10 and involucrin, and the AhR downstream protein CYP1A1 were reduced after AhR silencing. To the best of our knowledge, we provide evidence that in the absence of exogenous ligands, the AhR inhibits lipid synthesis and involves in cell differentiation of human SZ95 sebocytes, which indicates the physiological function of this receptor in human sebocytes. [ABSTRACT FROM AUTHOR]

Background: Reflectance confocal microscopy (RCM) is a noninvasive technique for evaluating cutaneous lesions with cellular level resolution close to conventional histopathology. The aim of this study is to observe the vascular changes in Port-wine (PWS) lesions and assess the clinical efficacy of Pulsed Dye Laser (PDL) treatment by examining vessel diameter and density with RCM. Materials and methods: Eleven adult patients with PWS, each had four test patches carried out with different pulse durations (1.5, 3, 6, and 10 ms), respectively; fluences of 9-12 J/cm2; and a spot size of 7 mm. The PDL treatment was repeated 3-5 times at a 2-month interval. Photographs and measurements with RCM were taken before each treatment and 2 months after the last treatment. Results: The PDL treatment exhibited increasing clearance with reducing pulse durations. Vessel diameters and densities were significantly decreased in the same pulse-duration groups after treatment. There was significant difference between 1.5 ms pulse-duration group and other pulse-duration groups in reducing blood vessel diameter at the depth of 150 μm. Conclusions: RCM can be used to assess the clinical efficacy of PDL treatment. [ABSTRACT FROM AUTHOR]