Melanocytes and melanin granules have been studied by electron microscopy in normal human and cat skin, and in hyperplastic human skin lesions. The melanocytes have always been found as free cells within the epidermis,i.e., on the epidermal side of the dermal membrane. Melanocytes frequently rest on the dermal membrane or bulge towards the dermis. In such cases the uninterrupted dermal membrane...

Encapsulation of chemicals in liposomes and microneedling are currently used techniques to enhance the penetration of several substances through skin and hair. In this study, we apply a liposomal melanin-fluorescein compound to an ex vivo model of human skin, using a new electrical microneedling device (Nanopore turbo roller). The product was applied by hand massage (A) or with the assistance o...

Melanocytes are melanin-producing cells found in skin, hair follicles, eyes, inner ear, bones, heart and brain of humans. They arise from pluripotent neural crest cells and differentiate in response to a complex network of interacting regulatory pathways. Melanins are pigment molecules that are endogenously synthesized by melanocytes. The light absorption of melanin in skin and hair leads to ph...

This study was performed to assess changes in skin color over 1 month after smoking cessation. The study population consisted of 49 men who participated in a smoking cessation program from March 2010 to June 2010 at a public health centre in Yangsan, South Korea. Thirty-four men who stop smoking completely were included in our study. Instrumental evaluations of skin color were performed using M...

The intracellular signal pathways that mediate pigmentation in human skin are unknown. We now report that a diacylglycerol (DAG) analogue 1-oleoyl-2-acetyl-glycerol (OAG) 25-100 microns strikingly increased the melanin content of cultured human melanocytes in a dose dependent manner without altering growth rate. The pigment increase occurred within 24 h, was accompanied by increased incorporati...

The present study was designed to investigate the anti-melanogenic and cytotoxic activities of methanol extract of Phlomis kurdica. The antioxidant and anti-tyrosinase activity of MeOH extract from P. kurdica (MPk) were examined by DPPH radical scavenging and mushroom tyrosinase activity assays (in vitro), respectively. Furthermore, the effect of MPk on the melanin content, cellular tyrosinase ...

Human skin color is predominantly determined by melanin produced in melanosomes within melanocytes and subsequently distributed to keratinocytes. There are many studies that have proposed mechanisms underlying ethnic skin color variations, whereas the processes involved from melanin synthesis in melanocytes to the transfer of melanosomes to keratinocytes are common among humans. Apart from the ...

The sulfhydryl group plays a role in the biological formation of melanin. Mechanisms suggested for the inverse relationship between the sulfhydryl group and the formation of melanin in mammalian skin include inhibition of tyrosinase and reaction with precursors of melanin (1, 2). However, knowledge in this field is fragmentary, and definitive proof of mechanism is lacking (3). The present work ...

The sulfhydryl group plays a role in the biological formation of melanin. Mechanisms suggested for the inverse relationship between the sulfhydryl group and the formation of melanin in mammalian skin include inhibition of tyrosinase and reaction with precursors of melanin (1, 2). However, knowledge in this field is fragmentary, and definitive proof of mechanism is lacking (3). The present work ...