Laser treatment after topical TC cream was found to be safer and more effective than the post-treatment use of topical agents.

The low-fluence 1064-nm Q-switched neodymium:yttrium-aluminium-garnet (QSNY) laser is a widely used treatment for melasma in East Asia, although its mechanism of action is unclear. The aim of this study was to elucidate the mechanism of action of the QSNY laser. We performed a histopathological study on eight Korean women who had considerable improvement in their melasma lesions after a series of low-fluence QSNY laser treatments. Compared with nonlesional skin, samples from melasma lesions showed increased reactivity in melanin (Fontana-Masson staining) and in melanogenesis-associated proteins, including α-melanocyte-stimulating hormone, tyrosinase, tyrosinase-related protein (TRP)-1, TRP-2, nerve growth factor and stem cell factor. After laser treatment, the melasma skin showed a decrease in the number of melanosomes and reduced expression of melanogenesis-associated proteins. Expression levels of the melanogenic proteins were reduced after laser treatment, although the number of melanocytes was unchanged even in hypopigmented areas. Based on these results, we believe that repeated application of low thermal energy via QSNY laser may result in damage to melanocytes and long-lasting hypopigmentation.

Background and ObjectivesMultipotent mesenchymal stem cells (MSCs) represent a promising cell-based therapy for a number of degenerative conditions. Understanding the effect of aging on MSCs is crucial for both autologous therapy development and allogenic donors in older subjects whom degenerative diseases typically afflict. In this study, we investigated the influence of donor age on the characteristics, proliferation, and differentiation potential of in vitro cultures of multipotent human turbinated mesenchymal stem cells (hTMSCs) from patients of various age groups.Subjects and MethodsTwelve patients comprised the four age groups: (I) <20 years, (II) 20–39 years, (III) 40–59 years, and (IV) >60 years. Inferior turbinate tissues were discarded from patients undergoing partial turbinectomy. After isolating hTMSCs, the expression of the hTMSC surface markers CD14, CD19, CD34, CD73, CD90, CD105, and HLA-DR was assessed by FACS analysis, and cell proliferation was assessed using a cell counting kit (CCK)-8. The differentiation potential of hTMSCs was evaluated in osteogenic media by histology and determination of osteoblastic gene expression.ResultsFACS analysis revealed that hTMSCs were negative for CD14, CD19, CD34, and HLA-DR, and positive for CD73, CD90, and CD105, representing a characteristic MSC phenotype, and showed no significant differences among the age groups. Cellular proliferation and osteogenic differentiation potential of hTMSCs also showed no significant differences among the age groups.ConclusionsWe conclude that donor age does not affect the characteristics, proliferation, and osteogenic differentiation potential of hTMSCs. Donor age may be excluded as a criterion in the guidelines for clinical use of the autologous or allogenic transplantation of hTMSCs.

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McCune-Albright syndrome (MAS) is a sporadic disease characterized by café-au-lait spots, polyostotic fibrous dysplasia and hyperfunctional endocrinopathies. To elucidate the mechanism of skin pigmentation, melanocytes, keratinocytes and fibroblasts were primary cultured from the café-au-lait spot of a MAS patient. Then, mutational analysis and morphologic evaluation were performed. Also, cAMP level and tyrosinase gene expression in cultured cells were determined. Only Gsα mutation was found in affected melanocytes and the cAMP level in affected melanocytes was higher than that of normal melanocytes. The mRNA expression of tyrosinase gene was increased in the affected melanocytes. This study suggests that skin pigmentation of MAS results from activating mutation of Gsα in melanocytes and the mechanism involves the c-AMP-mediated tyrosinase gene activation.