scholarly journals Melatonin and its metabolites accumulate in the human epidermis in vivo and inhibit proliferation and tyrosinase activity in epidermal melanocytes in vitro

2015 ◽  
Vol 404 ◽  
pp. 1-8 ◽  
Author(s):  
Tae-Kang Kim ◽  
Zongtao Lin ◽  
William J. Tidwell ◽  
We Li ◽  
Andrzej T. Slominski
Keyword(s):  
Tyrosinase Activity ◽  
Human Epidermis

Effect of α-melanocyte-stimulating hormone on tyrosinase activity in hair follicular and epidermal melanocytes of the mouse

1988 ◽  
Vol 119 (3) ◽  
pp. 517-522 ◽  
Author(s):  
P. Seechurn ◽  
S. A. Burchill ◽  
A. J. Thody
Keyword(s):  
Tyrosinase Activity ◽  
In Vitro Experiments ◽  
Dorsal Skin ◽  
Wild Type ◽  
Melanocyte Stimulating Hormone ◽  
Tyrosinase Expression ◽  
In Vivo Administration ◽  
Agouti Gene

ABSTRACT In this study, the effect of α-MSH on tyrosinase activity was compared in epidermal and hair follicular melanocytes of mice. It had no effect on epidermal tyrosinase activity in dorsal skin from neonatal non-agouti black mice (C57BL/6J) in both in-vivo and in-vitro experiments. Theophylline and 8-bromocyclic (c)AMP were similarly without effect in in-vitro experiments. In-vivo administration of α-MSH and theophylline for 7 days was also without effect on epidermal tyrosinase activity in ear skin of adult non-agouti mice, and the same was true for α-MSH in wild-type agouti mice. Activation of the epidermal melanocytes in the non-agouti and wild-type agouti mice with ultraviolet radiation also failed to bring about a response to α-MSH and to theophylline in the case of the former. No tyrosinase activity was detected in the epidermis of viable yellow mice (C3H-HeAvy), but, as shown previously, tyrosinase activity was present in the hair follicle when the hair was actively growing and was increased in those mice given either α-MSH or theophylline. α-MSH and theophylline had no such effects on hair follicular tyrosinase activity in the non-agouti mice. The present results suggest that α-MSH- and cAMP-dependent mechanisms have little or no importance in the regulation of tyrosinase expression in mouse epidermal melanocytes. α-MSH may, however, regulate tyrosinase expression in hair follicular melanocytes, but even in these melanocytes its action may be restricted to mice that express the agouti gene. J. Endocr. (1988) 119, 517–522

scholarly journals FGIN-1-27 Inhibits Melanogenesis by Regulating Protein Kinase A/cAMP-Responsive Element-Binding, Protein Kinase C-β, and Mitogen-Activated Protein Kinase Pathways

2020 ◽  
Vol 11 ◽  
Author(s):  
Jinpeng Lv ◽  
Songzhou Jiang ◽  
Ying Yang ◽  
Ximei Zhang ◽  
Rongyin Gao ◽  
...  
Keyword(s):  
Protein Kinase ◽  
The Body ◽  
Tyrosinase Activity ◽  
Mitogen Activated Protein Kinase ◽  
Mushroom Tyrosinase ◽  
Mitogen Activated Protein ◽  
Element Binding Protein ◽  
Responsive Element

FGIN-1-27 is a synthetic mitochondrial diazepam binding inhibitor receptor (MDR) agonist that has demonstrated pro-apoptotic, anti-anxiety, and steroidogenic activity in various studies. Here we report, for the first time, the anti-melanogenic efficacy of FGIN-1-27 in vitro and in vivo. FGIN-1-27 significantly inhibited basal and α-melanocyte-stimulating hormone (α-MSH)-, 1-Oleoyl-2-acetyl-sn-glycerol (OAG)- and Endothelin-1 (ET-1)-induced melanogenesis without cellular toxicity. Mushroom tyrosinase activity assay showed that FGIN-1-27 did not directly inhibit tyrosinase activity, which suggested that FGIN-1-27 was not a direct inhibitor of tyrosinase. Although it was not capable of modulating the catalytic activity of mushroom tyrosinase in vitro, FGIN-1-27 downregulated the expression levels of key proteins that function in melanogenesis. FGIN-1-27 played these functions mainly by suppressing the PKA/CREB, PKC-β, and MAPK pathways. Once inactivated, it decreased the expression of MITF, tyrosinase, TRP-1, TRP-2, and inhibited the tyrosinase activity, finally inhibiting melanogenesis. During in vivo experiments, FGIN-1-27 inhibited the body pigmentation of zebrafish and reduced UVB-induced hyperpigmentation in guinea pig skin, but not a reduction of numbers of melanocytes. Our findings indicated that FGIN-1-27 exhibited no cytotoxicity and inhibited melanogenesis in both in vitro and in vivo models. It may prove quite useful as a safer skin-whitening agent.

scholarly journals Nanostructured Lipid Carrier Gel for the Dermal Application of Lidocaine: Comparison of Skin Penetration Testing Methods

Pharmaceutics ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 310 ◽  
Author(s):  
Stella Zsikó ◽  
Kendra Cutcher ◽  
Anita Kovács ◽  
Mária Budai-Szűcs ◽  
Attila Gácsi ◽  
...  
Keyword(s):  
Drug Release ◽  
Human Skin ◽  
Ex Vivo ◽  
Study Drug ◽  
Skin Penetration ◽  
Human Epidermis ◽  
Nanostructured Lipid Carrier ◽  
Experimental Findings

The aim of this research was to investigate the stability of a lidocaine-loaded nanostructured lipid carrier dispersion at different temperatures, formulate a nanostructured lipid carrier gel, and test the penetration profile of lidocaine from the nanostructured lipid carrier gel using different skin penetration modeling methods. The formulations were characterized by laser diffraction, rheological measurements and microscopic examinations. Various in vitro methods were used to study drug release, diffusion and penetration. Two types of vertical Franz diffusion cells with three different membranes, including cellulose, Strat-M®, and heat separated human epidermis were used and compared to the Skin-parallel artificial membrane permeability assay (PAMPA) method. Results indicated that the nanostructured lipid carrier dispersion had to be gelified as soon as possible for proper stability. Both the Skin-PAMPA model and Strat-M® membranes correlated favorably with heat separated human epidermis in this research, with the Strat-M® membranes sharing the most similar drug permeability profile to an ex vivo human skin model. Our experimental findings suggest that even when the best available in vitro experiment is selected for modeling human skin penetration to study nanostructured lipid carrier gel systems, relevant in vitro/in vivo correlation should be made to calculate the drug release/permeation in vivo. Future investigations in this field are still needed to demonstrate the influence of membranes and equipment from other classes on other drug candidates.

THE MELANOGENIC RESPONSE TO TESTOSTERONE IN SCROTAL EPIDERMIS: EFFECTS ON TYROSINASE ACTIVITY AND PROTEIN SYNTHESIS

1976 ◽  
Vol 81 (2) ◽  
pp. 435-448 ◽  
Author(s):  
Michael J. Wilson ◽  
Eugene Spaziani
Keyword(s):  
Protein Synthesis ◽  
Specific Protein ◽  
Tyrosinase Activity ◽  
Melanin Synthesis ◽  
Testosterone Treatment ◽  
Pre Treatment ◽  
Inhibitor Of Protein Synthesis ◽  
Rate Limiting

ABSTRACT Pigmentation of the scrotum of the black-pelted rat, as expressed through melanocyte melanogenic activity, is controlled by androgens. Castration decreased in vitro incorporation of [14C] tyrosine into melanin. Testosterone pre-treatment for 4 days increased melanin radioactivity over castrate controls; the increment in vitro was prevented by an inhibitor of protein synthesis (cycloheximide) added to the incubation. However, cycloheximide only partially blocked melanin synthesis when added to tissue from animals hormone treated for 6 days in vivo, and was ineffective in tissue from intacts. Bulk protein synthesis in vitro (incorporation of [14C] tyrosine or -leucine) was not affected by castration or testosterone treatment but was uniformly inhibited by cycloheximide. The data suggest that new synthesis of specific protein in vitro was necessary for initial hormone-stimulation of melanogenesis, but with longer exposure to hormone sufficient protein was pre-synthetized in vivo to permit melanogenesis during incubation with the inhibitor. Radioautographs of epidermis incubated with [14C] tyrosine showed grains concentrated over macromolecular aggregates in melanocytes, a pattern not altered by cycloheximide. Though available for incorporation into general tissue protein. [14C] tyrosine was apparently incorporated preferentially into melanin by melanocytes. DOPA (3,4-dihydroxyphenylalanine) added to incubations in cofactor amounts did not affect decreased melanin synthesis after castration and appears, therefore, not to be rate limiting in that decrease. Tissue uptake of free [14C] tyrosine or — leucine during incubation was lower than normal in castrate epidermis; uptake was elevated by testosterone treatment. Concentrations appeared sufficient in all preparations to suggest that availability is not rate limiting for synthesis of melanin or protein; however, a possible influence on amino acid permeability for melanocytes remains undetermined. Tyrosinase activity was present in both particulate and cytosol fractions of epidermis but decreased significantly after castration only in the cytosol. Testosterone increased particulate activity after 4 days and soluble activity after 9 days of treatment. These and findings above are consistent with a model that tyrosinase is synthesized and incorporated into melanosome structure within 4 days testosterone treatment; with longer treatment synthesis may then exceed that required for melanosome assembly and tyrosinase appears in the soluble milieu.

Oxyresveratrol extracted from Artocarpus heterophyllus Lam. inhibits tyrosinase and age pigments in vitro and in vivo

2020 ◽  
Vol 11 (7) ◽  
pp. 6595-6607 ◽  
Author(s):  
Jun Li ◽  
Zhenyu Lin ◽  
Xudong Tang ◽  
Guo Liu ◽  
Yunjiao Chen ◽  
...  
Keyword(s):  
Tyrosinase Activity ◽  
Melanin Production ◽  
Artocarpus Heterophyllus

Oxyresveratrol could strongly inhibit tyrosinase activity and decrease melanin production in vitro and in vivo.

Attenuation of In Vitro and In Vivo Melanin Synthesis using a Chinese Herbal Medicine through the Inhibition of Tyrosinase Activity

Phytomedicine ◽  
2021 ◽  
pp. 153876
Author(s):  
Shu-Chun Liu ◽  
Meei-Ling Sheu ◽  
Yi-Ching Tsai ◽  
Yu-Chin Lin ◽  
Ching-Wen Chang ◽  
...  
Keyword(s):  
Herbal Medicine ◽  
Chinese Herbal Medicine ◽  
Tyrosinase Activity ◽  
Melanin Synthesis ◽  
Chinese Herbal

scholarly journals Inhibitory Effect of Arctigenin from Fructus Arctii Extract on Melanin Synthesis via Repression of Tyrosinase Expression

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Hwayong Park ◽  
Kwang Hoon Song ◽  
Pil Mun Jung ◽  
Ji-Eun Kim ◽  
Hyunju Ro ◽  
...  
Keyword(s):  
Active Compound ◽  
Gene Promoter ◽  
Inhibitory Effect ◽  
Tyrosinase Activity ◽  
Dependent Manner ◽  
Melanin Content ◽  
Extracellular Signal Regulated Kinase ◽  
Extracellular Signal

To identify the active compound arctigenin in Fructus Arctii (dried seed of medicinal plantArctium lappa) and to elucidate the inhibitory mechanism in melanogenesis, we analyzed melanin content and tyrosinase activity on B16BL6 murine melanoma and melan-A cell cultures. Water extracts of Fructus Arctii were shown to inhibit tyrosinase activity in vitro and melanin content inα-melanocyte stimulating hormone-stimulated cells to similar levels as the well-known kojic acid and arbutin, respectively. The active compound arctigenin of Fructus Arctii displayed little or no cytotoxicity at all concentrations examined and decreased the relative melanin content and tyrosinase activity in a dose-dependent manner. Melanogenic inhibitory activity was also identified in vivo with zebrafish embryo. To determine the mechanism of inhibition, the effects of arctigenin on tyrosinase gene expression and tyrosinase promoter activity were examined. Also in addition, in the signaling cascade, arctigenin dose dependently decreased the cAMP level and promoted the phosphorylation of extracellular signal-regulated kinase. This result suggests that arctigenin downregulates cAMP and the tyrosinase enzyme through its gene promoter and subsequently upregulates extracellular signal-regulated kinase activity by increasing phosphorylation in the melanogenesis signaling pathway, which leads to a lower melanin content.

scholarly journals Tyrosinase activity and melanogenic effects of Lespedeza bicolor extract in vitro and in vivo

BioResources ◽  
2020 ◽  
Vol 15 (3) ◽  
pp. 6244-6261
Author(s):  
Si Young Ha ◽  
Ji Young Jung ◽  
Hee Young Kang ◽  
Tae-Heung Kim ◽  
Jae-Kyung Yang
Keyword(s):  
Ethanol Extract ◽  
Melanoma Cells ◽  
B16 Melanoma ◽  
Tyrosinase Activity ◽  
Melanin Content ◽  
B16 Melanoma Cells ◽  
Notable Increase ◽  
Lespedeza Bicolor

Lespedeza bicolor (L. bicolor) is used for medicinal purposes because of its various biological and pharmacological activities. In this study, the effects of L. bicolor ethanol extract on the treatment of vitiligo were investigated. The determination of melanin content in melanocytes was measured using B16 melanoma cells and C57BL/6J Ler-vit/vit mice. Finally, the quercetin content in L. bicolor were qualitatively analyzed using HPLC. The results obviously indicated that the L. bicolor extract enhanced melanogenesis and increased tyrosinase activity in cultured melanoma cells and C57BL/6J Ler-vit/vit mice. Treatment with L. bicolor extract led to a higher content of melanin and eumelanin in C57BL/6J Ler-vit/vit mice hair than in control (untreated) mice, which demonstrated the therapeutic effect of hair-graying associated with vitiligo. There was a notable increase in melanocytes in the skin of C57BL/6J Ler-vit/vit mice treated with L. bicolor extract compared with the control. L. bicolor extract was a potent tyrosinase and melanin synthesis activator in B16 melanoma cells. C57BL/6J Ler-vit/vit mice treated with L. bicolor extract had significantly higher melanin content in hair than the untreated control. The results suggest that L. bicolor extract is a potential alternative treatment for improvement of vitiligo.

Delivery of ethinylestradiol from film forming polymeric solutions across human epidermis in vitro and in vivo in pigs

2007 ◽  
Vol 118 (2) ◽  
pp. 196-203 ◽  
Author(s):  
Ines Zurdo Schroeder ◽  
Patrick Franke ◽  
Ulrich F. Schaefer ◽  
Claus-Michael Lehr
Keyword(s):  
Human Epidermis ◽  
Film Forming ◽  
Polymeric Solutions
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