The effects of prostaglandins (PCs) on the ( loudman S91 melanoma CCL 53.1 cell line indicate that melanogenesis and proliferation are regulated by separate mechanisms that are not necessarily cyclic AMP (cAMP) dependent. These cells responded to PGEi and PGE2 in a dosedependent manner, by an increase of tyrosinase activity and by inhibition of proliferation. PGAi and PGD2 inhibited cellular pr...

The effects of prostaglandins (PGs) on the Cloudman S91 melanoma CCL 53.1 cell line indicate that melanogenesis and proliferation are regulated by separate mechanisms that are not necessarily cyclic AMP (cAMP) dependent. These cells responded to PGE1 and PGE2 in a dose-dependent manner, by an increase of tyrosinase activity and by inhibition of proliferation. PGA1 and PGD2 inhibited cellular pr...

skin and hair, and is synthesized in melanosomes transferred from melanocytes. Although melanin plays an important protective role against UV light, over production and accumulation of melanin pigment it could create serious skin problems such as freckles, age spots, and melasma. Thus, the inhibition of melanogenesis has been the focus of medicinal and cosmetic treatments for skin depigmenting ...

BACKGROUND Fucoidan is a complex sulfated polysaccharide extracted from brown seaweed and has a wide variety of biological activities. It not only inhibits cancer cell growth but also inhibits tyrosinase in vitro. Therefore, it is of interest to investigate the effect of fucoidan on B16 murine melanoma cells as the findings may provide new insights into the underlying mechanism regarding the in...

Tyrosinases are responsible for melanin formation in all life domains. Tyrosinase inhibitors are used for the prevention of severe skin diseases, in skin-whitening creams and to avoid fruit browning, however continued use of many such inhibitors is considered unsafe. In this study we provide conclusive evidence of the inhibition mechanism of two well studied tyrosinase inhibitors, KA (kojic aci...

Marigold (Tagetes erecta L.) has long been used as a medicinal herb for a number of therapeutic activities. In the present study, the cytotoxicities of ethanol and ethyl acetate extracts of marigold flowers and their inhibitory effects on elastase and tyrosinase enzymes were investigated. An MTT assay was performed to measure the cytotoxicity of these two extracts on the H460 lung cancer and th...

Background and objectives: Phytochemical studies have shown that the Phlomis species are rich in polyphenolics and iridoid glycosides and many of them have shown potential value in different biological and pharmacological activities. In this study, we evaluated the effect of Phlomis persica, P. brugieri, P. olivieri and P. anisodontea</em...

Tyrosinase is a bifunctional enzyme which oxidizes the initial step of melanin biosynthesis, that is, conversion of tyrosine to dopa and subsequently dopa to dopaquinone. It is a glycosylated protein and a major regulator of melanogenesis. To date, many approaches have been tried to regulate tyrosinase activity and melanin content. To that end, we screened small interfering RNA sequences for se...

BACKGROUND Ultraviolet radiation from sunlight induces overproduction of reactive oxygen species (ROS) resulting in skin photoaging and hyperpigmentation disorders. Novel whitening and anti-wrinkle compounds from natural products have recently become of increasing interest. The purpose of this study was to find products that reduce ROS in 14 Thai plant extracts. METHODS To determine total phe...

The aim of the present study is to preliminarily investigate the antimelanogenesis effect of Inonotus obliquus extracts by cell-free mushroom tyrosinase assay. It was found that petroleum ether and n-butanol extracts might contain unknown potential tyrosinase inhibitors, while its ethyl acetate extract might contain some unknown accelerators. Six compounds were isolated and their structures wer...