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Blackcurrants (Ribes nigrum L.) have various benefits for human health. In particular, a polysaccharide derived from blackcurrant was found to be an immunostimulating food ingredient in a mouse model. We named a polysaccharide derived from blackcurrant cassis polysaccharide (CAPS). In a previous clinical study, we reported that CAPS affects skin dehydration, demonstrating its effectiveness against skin inflammation was related to atopic dermatitis; skin inflammation caused skin dehydration. However, there are no studies regarding CAPS effectiveness against skin dehydration. The current study aimed to investigate CAPS effectiveness against skin dehydration. We further demonstrate the effect of oral administration of CAPS on skin dehydration caused by ultraviolet (UV) irradiation-induced inflammation in mice. We found that CAPS administration suppresses skin dehydration caused by UV irradiation. We also found that CAPS decreases interleukin-6 and matrix metalloproteinase transcription levels in the mouse skin. These results show that CAPS improves skin hydration in UV-irradiated mice.

Background: UVB radiation is the main source of sunburn and skin cancers. Apoptosis eliminates photodamaged cells, and is thus important for preventing epidermal carcinogenesis. The cytoplasmic regulatory protein p62/A170/sequestosome 1 (p62) molecule is involved in a variety of cellular and signaling pathways. p62 is known to be and important in autophagy, but its role in UVB-induced apoptosis remains to be clarified., Objective: To investigate the role of p62 against UVB-induced apoptotic changes, using mouse embryonic fibroblasts (MEFs) derived from p62 homozygous knockout (p62(-/-)) mice., Methods: p62(-/-) and wild-type (p62(+/+)) mice and MEFs were subjected to UVB irradiation, and the resultant apoptosis was analyzed using flow cytometry, quantitative real-time PCR, and western blots., Results: Apoptosis was decreased in the p62(-/-) MEFs compared to p62(+/+) MEFs in response to UVB treatment. Compared with p62(+/+) MEFs, p62(-/-) MEFs expressed significantly more Bcl-2 and less Bax, and showed increased Src and Stat3 phosphorylation. Our results show that p62 regulates apoptotic pathways by modifying critical signaling intermediates such as Src and Stat3., Conclusion: p62 deficiency [corrected] reduces UVB-induced apoptosis by modulating intrinsic apoptotic signaling through Src phosphorylation., (Copyright © 2016 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.)

Background: Exposure of skin to long-wave UV radiation (UVA) increases the cellular levels of reactive oxygen species (ROS), which have been linked to apoptosis induction through the damage of lipids, proteins, and nucleic acids. Peroxiredoxin I (Prx I) is one of a family of antioxidant proteins that plays a protective role against oxidative damage; however the role of Prx I in UVA-induced damage remains to be clarified., Objective: Here we investigated the protective role of Prx I against UVA-induced changes using mouse embryonic fibroblasts (MEFs) derived from Prx I homozygous knockout (Prx I (-/-)) mice., Methods: Prx I (-/-) and wild-type (Prx I (+/+)) MEFs were subjected to UVA irradiation, and the resulting apoptosis was analyzed using flow cytometry, quantitative real-time PCR, and western blotting., Results: Prx I (-/-) MEFs showed enhanced sensitivity to UVA treatment, exhibiting increased apoptosis and ROS production compared to Prx I (+/+) MEFs. Consistent with the increase in apoptosis, p53 expression was significantly higher, while Bcl-2, Bcl-xL, and Nrf2 expressions were all lower in Prx I (-/-) versus (+/+) MEFs. The UVA-induced inflammatory response was upregulated in Prx I (-/-) MEFs, as indicated by increased expressions of IκB, TNFα, and IL-6. Evidence was presented indicating that Prx I impacts these pathways by modifying critical signaling intermediates including p53, IκB, and Nrf2., Conclusion: Our results indicate that Prx I plays a protective role against UVA-induced oxidative damage by controlling ROS accumulation. Both the UVA-induced apoptotic and inflammatory signals were found to be modulated by Prx I., (Copyright © 2013 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.)

We describe a female neonate with large flaccid pustules on her trunk and extremities. Cultures were negative, and a Wright-stained smear of pustule contents showed numerous eosinophils (>90%). The pustules resolved without leaving pigmentation after 2 weeks. We diagnosed this case as sterile transient neonatal pustulosis., (© 2012 Wiley Periodicals, Inc.)

Ultraviolet (UV) radiation is one of the most important environmental factors involved in the pathogenesis of premature skin ageing, termed photoageing. The harmful effects of UV in photoageing are associated with the generation of reactive oxygen species, and cellular antioxidants act to prevent the occurrence and reduce the severity of UV-induced photoageing. The transcription factor Nrf2 and its cytoplasmic anchor protein, Keap1, are central regulators of the cellular antioxidant response. Here, we investigated the role of the Nrf2-Keap1 pathway in photoageing using nrf2 gene-deficient (nrf2(-/-)) mice. Our results indicated that UVB-irradiated nrf2(-/-) mice showed accelerated photoageing, such as coarse wrinkle formation, loss of skin flexibility, epidermal thickening and deposition of extracellular matrix in the upper dermis. In addition, nrf2(-/-) mice also showed an increase in cutaneous reactivity for the lipid peroxidation product 4-hydroxy-2-nonenal and a significant decrease in cutaneous glutathione level. These findings indicate that Nrf2 plays the important role in the protection against UVB-induced photoageing., (© 2011 John Wiley & Sons A/S.)

The beta-catenin/TCF signaling pathway is essential for the maintenance of epithelial stem cells in the small intestine. c-Myc a downstream target of beta-catenin/TCF (ref. 2), can induce differentiation of epidermal stem cells in vitro. To determine the role of c-Myc in epidermal stem cells in vivo, we have targeted expression of human MYC2 to the hair follicles and the basal layer of mouse epidermis using a keratin 14 vector (K14.MYC2). Adult K14.MYC2 mice gradually lose their hair and develop spontaneous ulcerated lesions due to a severe impairment in wound healing; their keratinocytes show impaired migration in response to wounding. The expression of beta1 integrin, which is preferentially expressed in epidermal stem cells is unusually low in the epidermis of K14.MYC2 mice. Label-retaining analysis to identify epidermal stem cells reveals a 75% reduction in the number of stem cells in 3-month-old K14.MYC2 mice, compared with wildtype mice. We conclude that deregulated expression of c-Myc in stem cells reduces beta1 integrin expression, which is essential to both keratinocyte migration and stem cell maintenance.

A 26-year-old woman was admitted to our hospital for lumbago on November 29, 1995. The white blood cell count was 6,500/microliter with 26.5% myeloblasts and the bone marrow was hyperplastic due to myeloblasts. Myeloblasts were negative for myeloperoxidase and positive for alpha-naphthyl butylate esterase, CD11a (89%), CD11b (38%), CD11c (92%), CD33 (91%) and HLA-DR (58%). Chromosomal abnormalities were recognized: 46, XX, t(9;11) (p22;q23), 45, XX, -7, t(9;11) (p22;q23) and 47, XX, +19, t(9;11) (p22;q23). Acute myeloblastic leukemia (M5a) was diagnosed. Disseminated intravascular coagulation was also present. The patient received induction therapy and achieved remission on January 9, 1996, but myeloblasts increased to 3.6% in bone marrow despite consolidation therapy. Low doses of cytarabine (AraC) and etoposide were instituted on March 7, granulocyte colony-stimulating factor (G-CSF) was started on March 15, and pronounced skin infiltration developed on March 18. The patient received reinduction therapy from April 16 and administration of G-CSF was combined for 2 days, and a marked increment of myeloblasts in the peripheral blood was observed. After discontinuation of G-CSF, myeloblasts decreased and skin infiltration disappeared. However, the patient died of cerebral infiltration on June 30. The response of myeloblasts to G-CSF by in vitro liquid culture was noteworthy. The present case stresses the requirement for great caution to be exercised in the use of G-CSF in patients receiving low dose AraC.

Tyrosine phosphorylation is widely recognized as playing an important role in cell differentiation, proliferation and carcinogenesis. We used the polymerase chain reaction (PCR) method to identify protein tyrosine kinases that were expressed in the skin. Mixed oligonucleotide probes were used to amplify and screen neonatal murine skin mRNA for clones encoding amino acid contiguities, the conservation of which is characteristic of the protein tyrosine kinase family. When the PCR products were sequenced, a novel clone encoding protein tyrosine kinase, PTK70, was identified. A full-length cDNA was isolated from a mouse thymus cDNA library. The nucleotide and deduced amino acid sequence showed that it featured src-homology (SH) 2 domain, SH3 domain and kinase domain like other src family protein tyrosine kinases, but lacked the N-terminal myristylation site and C-terminal tyrosine residue. Although the mRNA of PTK70 was detected in various tissues ubiquitously, the degree of its expression differed among tissues. Murine skin is one in which PTK70 was expressed strongly, with its expression being much stronger in the epidermis and in the cell line derived from murine keratinocytes than in those from melanoma or fibroblast cell lines. These evidences suggest that PTK70 may be involved in proliferation or differentiation of keratinocytes in the skin.

Background: The patient with xeroderma pigmentosum provides an appropriate human model for the evaluation of tumor development and progression., Methods: We describe a patient with variant-type xeroderma pigmentosum who developed actinic keratoses, a squamous cell carcinoma, and its metastasis into a lymph node. DNA ploidy was measured and analyzed in cells of these tumors and the patient's sun-exposed as well as sun-shielded skin., Results: The sun-shielded skin showed a normal diploid DNA distribution pattern, while the sun-exposed skin had an increased number of hyperdiploid cells. The actinic keratosis showed further increased hyperdiploid cells. The squamous cell carcinoma showed a large number of hyperdiploid cells and formed an aneuploid cell fraction. Histographically, the aneuploid cell fraction became more apparent and was revealed to be a major fraction in the metastatic squamous cell carcinoma., Conclusions: The changes in the DNA ploidy pattern well reflect the clinical and histologic characteristics of the respective skin conditions and likely provide the cellular basis for the sequential or stepwise carcinogenic process in the patient's xeroderma pigmentosum skin. Further studies are necessary to determine whether the present results explain the similar carcinogenic process in sun-damaged skin of the nonpredisposed general population.

Tyrosine phosphorylation is widely recognized as playing important roles in cell differentiation, proliferation, and carcinogenesis. We have used the polymerase chain reaction (PCR) method to identify protein tyrosine kinases that are expressed in the skin. Mixed oligonucleotide probes were used to amplify and screen a neonatal murine skin cDNA pool for clones encoding amino acid contiguities whose conservation is characteristic of the protein tyrosine kinase family. When the PCR products were sequenced, 13 distinct clones were found, of which one is novel to date and has provisionally been named tks (for tyrosine kinase identified from skin). Sequence homology comparison showed that the tks gene is homologous to the src and fes/fps families. Northern blotting using PCR products of tks as a probe revealed that the mRNA of tks is detected ubiquitously and weakly in other tissues such as brain, lung, liver, thymus and kidney. This fact suggests that the tks gene is expressed in widely distributed cell types.