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 ...

Alleviated melanin formation in the skin through inhibition of tyrosine-tyrosinase reaction is one of the major targets of cosmetics for whitening ability. Since melanin has a pivotal role for photoprotection, there are pros and cons of inhibition of melanin formation. This study applying electron spin resonance (ESR)-spin trapping method revealed that (•)H and (•)OH are generated through tyros...

Minocycline is a commonly used antibiotic for long-term treatment of acne vulgaris. A well-documented and cosmetically dis-pleasing side effect is skin pigmentation. Three distinct types occur: Type I, blue-black/grey pigment on the face in areas of scarring or inflammation associated with acne; type II, blue-grey pigment on normal skin on the shins and forearms; type III, diffuse muddy-brown d...

During the past several years we have been studying a number of melanogenic attributes using the skins of house mice afflicted by various types of genetic damage (Foster, 1956, 1959; Foster and Thomson, 1958). Our most recent study (Foster and Thomson, 1961, and unpublished data) involves a closer scrutiny of the effects of allelic interactions at a specific locus, b (brown). Briefly, by means ...

Reduced or defective melanin skin pigmentation may cause many hypopigmentation disorders and increase the risk of damage to the skin triggered by UV irradiation. Ginsenosides Rb1 and Rg1 have many molecular targets including the cAMP-response element-binding protein (CREB), which is involved in melanogenesis. This study aimed to investigate the effects of ginsenosides Rb1 and Rg1 on melanogenes...

Melanin pigments in lower vertebrates are often found in locations other than the skin, thus forming an extracutaneous pigmentary system of unknown function. The cellular and biochemical structure of this system is still poorly characterized. This paper deals with the ultrastructural and biochemical features of the melanogenic system of Xenopus laevis. Melanin containing cells were identified i...

Recent studies have shown that plumbagin has anti-inflammatory, anti-allergic, antibacterial, and anti-cancer activities; however, it has not yet been shown whether plumbagin suppresses alpha-melanocyte stimulating hormone (α-MSH)-induced melanin synthesis to prevent hyperpigmentation. In this study, we demonstrated that plumbagin significantly suppresses α-MSH-stimulated melanin synthesis in B...

Discoloration are symptoms of skin aging. They are connected with presence of melanin and lipofuscin, whose excess and abnormal distribution in the skin cause dark spots to appear. Melanin is formed under the influence of tyrosinase during melanogenesis. Its content changes with age, which may be a result of menopause. Lipofuscin is another example of the age pigment. It is composed of proteins...

We have developed a multimode dermoscope (SkinSpectTM) capable of illuminating human skin samples in-vivo with spectrally-programmable linearly-polarized light at 33 wavelengths between 468nm and 857 nm. Diffusely reflected photons are separated into collinear and cross-polarized image paths and images captured for each illumination wavelength. In vivo human skin nevi (N = 20) were evaluated wi...

In quest of alternate, extradermal path of melanin transfer from skin to the visceral organs, we suggested that some portions of such melanin may be deposited in the spleen, which in young black C57BL/6 mice is often melanized. Here, we confirm these observation using young C57BL/6 female mice (up to 17 weeks) and show that this phenomenon cannot be observed in old animals where the hair cycle ...