PURPOSE To study melanogenesis by cultured human uveal melanocytes, and the relationship between melanin production by uveal melanocytes in vitro with the degree of iris pigmentation in vivo. METHODS Melanin content, melanin production, and tyrosinase activity of cultured uveal melanocytes derived from eyes of various iris color were measured at different stages of cultivation. RESULTS Cult...

Cells of the C3 clone of B-16 melanoma synthesize melanin only at confluence after which they senesce and can no longer be passaged. Addition to the cultures of 10(-8)--10(-7) M 12-O-tetradecanoylphorbol-13-acetate (TPA) shortly after plating delayed by about 2 days the onset of melanogenesis. TPA did not, however, affect the growth of the cells or the time at which they reached confluence. The...

H19 non-coding RNA downregulation stimulates melanogenesis in melasma patients. However, its mechanism is unclear. In this study, the potential role of a H19 microRNA, miR-675, in melanogenesis was examined. Real-time PCR using cultured normal human skin keratinocytes, melanocytes, and fibroblasts with or without H19 knockdown showed accompanying changes between expression levels of H19 and tho...

The chemotherapeutical treatment is very limited for malignant melanoma, a highly lethal disease occurs globally. Natural products derived from traditional Chinese medicine licorice are attractive in quest new treatments due to their anti-tumor activities. A new dietary flavonoid isoliquiritigenin (ISL) were thus investigated to indentify its anti-melanoma activities on mouse melanoma B16F0 cel...

Stichopus japonicus has been used as a folk medicine and as an ingredient in traditional food in East Asian countries. In recent years, the bioactive compounds found in S. japonicus have been reported to possess efficacy in wound healing and may be of potential use in the cosmeceutical, pharmaceutical and biomedical industries. Although the components and their functions require further investi...

Melanogenesis is a well known physiological response of human skin exposed to ultraviolet light, genetic reasons and other sources. In this study, we conducted to evaluate the effects of Radix Ginseng (RG) and Radix Trichosanthis (RT) on the melanogenesis in the B16 melanoma cells. The cells were treated for 48 h with RT at concentrations ranging from 1 to 50 microg/ml, RG at concentration of 1...

Polydeoxyribonucleotide (PDRN), a deoxyribonucleotide polymer, is popularly used for faster healing of cutaneous wounds and boosting of neocollagenesis of photoaged skin among current dermatologic practitioners. Some patients receiving PDRN injection treatment also reported improvement of photoaging-associated mottled pigmentation (PMP). To investigate the effect of PDRN on cutaneous melanogene...

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 ...

The present study aimed to evaluate the anti-melanogenic activity of 1,6-diphenyl-1,3,5-hexatriene and its derivatives in B16F10 murine melanoma cells and zebrafish embryos. Twenty five (1E,3E,5E)-1,6-bis(substituted phenyl)hexa-1,3,5-triene analogs were synthesized and their non-cytotoxic effects were predictively analyzed using three-dimensional quantitative structure-activity relationship ap...

The exact pathogenesis of acne-related post-inflammatory hyperpigmentation (PIH) is unknown. It thought that epidermal inflammation induces the release arachidonic acid and its oxidation products, leading to melanocyte activation pigment production. Cutibacterium acnes (C. acnes) contributes keratinocyte in acne pathogenesis. In severe cases inflamed sebaceous follicles may be ruptured, thereby...