An Open Label Clinical Trial of a Multi-Ingredient Anti-Aging Moisturizer Designed to Improve the Appearance of Facial Skin

An open label clinical trial was conducted to determine the effectiveness of a multi-ingredient anti-aging moisturizer designed to improve the appearance of facial skin. Parameters studied included fine lines and wrinkles, clarity/brightness, visual roughness, tactile roughness, evenness of skin tone (redness), evenness of skin tone (hyperpigmentation) and overall appearance. Thirty-seven female subjects, ages 35-60 years completed the study. Effective ingredients incorporated into the facial anti-aging moisturizer include: Astragalus membranaceus root extract, a peptide blend including palmitoyl tripeptide-38, standardized rosemary leaf extract (ursolic acid), tetrahexyldecyl ascorbate (THD ascorbate) and ubiquinone (coenzyme Q10). Subjects were instructed to apply the moisturizer twice daily, once in the morning and once in the evening. Subjects were evaluated at baseline and after 4, 8, and 12 weeks of product usage. Clinical evaluations were conducted at each visit. A self-assessment questionnaire was conducted at week 4, week 8, and week 12. The self-assessment questionnaire included product efficacy inquiries and product aesthetic inquiries. Digital photography was conducted at baseline, week 8, and week 12. After 8 weeks of twice daily use, clinical evaluation results show that the multi-ingredient anti-aging moisturizer produced a statistically significant improvement in the scores of all clinical grading parameters assessed compared to baseline. A greater statistically significant improvement was seen at 12 weeks. At week 12, there was a statistically significant percentage of favorable results versus unfavorable results in all product efficacy and product aesthetic self-assessment questionnaire results. Digital photography supported the clinical grading and self-assessment questionnaire results. Additionally, the multi-ingredient anti-aging moisturizer is judged to be mild and well tolerated. Several tolerability parameters were assessed at all time points with no statistically significant increase in any of the scores compared to baseline.

Conditioned Media from Human Umbilical Cord Blood-Derived Mesenchymal Stem Cells Inhibits Melanogenesis by Promoting Proteasomal Degradation of MITF

Human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs) secrete various beneficial molecules, which have anti-apoptotic activity and cell proliferation. However, the effect of hUCB-MSCs in melanogenesis is largely unclear. In this study, we show that conditioned media (CM) derived from hUCB-MSCs inhibit melanogenesis by regulating microphthalmia-associated transcription factor (MITF) expression via the ERK signalling pathway. Treatment of hUCB-MSC-CM strongly inhibited the alpha-melanocyte stimulating hormone-induced hyperpigmentation in melanoma cells as well as melanocytes. Treatment of hUCB-MSC-CM induced ERK1/2 activation in melanocytes. In addition, inhibition of ERK1/2 suppressed the anti-pigmentation activity of the hUCB-MSC-CM in melanocytes and in vitro artificial skin models. We also found that the expression of MITF was appreciably diminished while expression of phosphorylated MITF, which leads to its proteasomal degradation, was increased in cells treated with hUCB-MSC-CM. These results suggested that hUCB-MSC-CM significantly suppresses melanin synthesis via MITF degradation by the ERK pathway activation.

Topical corticosteroids minimise the risk of postinflammatory hyper-pigmentation after ablative fractional CO2 laser resurfacing in Asians

Postinflammatory hyperpigmentation (PIH) is the most common adverse effect of laser treatment in dark-skinned individuals. Little is known whether PIH can be prevented or minimised. The objective of this study was to investigate the effect of short-term application of topical corticosteroids on the incidence of PIH after ablative fractional resurfacing in Asians. Forty subjects with skin phototype IV and atrophic acne scars were treated with a fractional CO2 laser on both sides of the face. Post-operatively, clobetasol propionate 0.05% ointment was applied to one randomly selected side of the face for the first 2 days, followed by an application of petrolatum jelly for the rest of the week (petrolatum was applied to the other side for 7 days). Assessments on the clinical outcome, the wound healing process and the occurrence of PIH were obtained once weekly for the first month and at 2 and 3 months post-treatment. The side of the face treated with petrolatum alone had significantly (p < 0.001) higher incidence of PIH (75%) after laser irradiation than the side of the face treated with topical corticosteroids and petrolatum (40%). The PIH occurring on the petrolatum-treated sides had significantly higher intensity (p < 0.001) and was spread over a significantly larger area (p < 0.001), compared with the corticosteroid- and petrolatum-treated sides. In conclusion, a short-term application of topical corticosteroids postoperatively is associated with a decreased risk of PIH after ablative fractional resurfacing.

Immunotherapy-induced leukoderma from treatment of melanoma with IL-2: a case report and a review of the literature

Melanoma-associated leukoderma (MAL) is a relatively uncommon phenomenon in the literature that can present (1) before melanoma detection, (2) after detection and before treatment, and (3) after treatment with immunotherapeutic agents. We report a case of MAL in an 83-year-old man after treatment with high dose IL-2 for metastatic melanoma and further describe the literature of the underlying mechanisms behind it that involve the immune system. Cytotoxic CD8+ T cells are thought the mediate the process at a cellular level. Self-antigens (e.g. MART-1/2, gp100, tyrosinase) have been presented on the surface of both normal and malignant melanocytes and mediate the development of MAL after cytotoxic CD8+ T cells attack both cell types. Autoimmune manifestations have a positive effect on tumor immunity, with patients at stage III and stage IV melanoma showing a better prognosis after leukoderma development. In addition, immunotherapy induced leukoderma has been associated with a higher therapeutic response rate. Recently, newer immuno-therapeutic drugs, such as vemurafenib and ipilimumab, have been associated with leukoderma as a side effect.

The neuro-hormonal control of rapid dynamic skin colour change in an amphibian during amplexus

Sexual signalling using dynamic skin colouration is a key feature in some vertebrates; however, it is rarely studied in amphibians. Consequently, little is known about the hormonal basis of this interesting biological phenomenon for many species. Male stony creek frogs (Litoria wilcoxii) are known to change dorsal colouration from brown to lemon yellow within minutes. This striking change is faster then what has been seen most amphibians, and could therefore be under neuronal regulation, a factor that is rarely observed in amphibians. In this study, we observed colour changes in wild frogs during amplexus to determine the natural timing of colour change. We also investigated the hypothesis that colour change is mediated by either reproductive or neuro- hormones. This was achieved by injecting frogs with epinephrine, testosterone, saline solution (control 1) or sesame oil (control 2). A non-invasive approach was also used wherein hormones and controls were administered topically. Male frogs turned a vivid yellow within 5 minutes of initiation of amplexus and remained so for 3-5 hours before rapidly fading back to brown. Epinephrine-treated frogs showed a significant colour change from brown to yellow within 5 minutes, however, testosterone-treated frogs did not change colour. Our results provide evidence of the role neuronal regulation plays in colour change systems.

Targeting melanocyte and melanoma stem cells by 8-hydroxy-2-dipropylaminotetralin

Monobenzyl ether of hydroquinone (MBEH) is cytotoxic towards melanocytes. Its treatment efficacy is limited by an inability to eradicate stem cells. By contrast, 8-hydroxy-N,N-dipropyl-2-aminotetralin (8-DPAT) affects melanocyte stem cell survival. MBEH and 8-DPAT were added to melanocytes and melanoma cells to compare cytotoxicity. Stem cell content among viable cells was determined by fluorocytometry using markers CD34, Pax3, and CD271. Immunostaining was used to identify stem cells in skin explants treated with MBEH or 8-DPAT ex vivo. Mice were exposed to MBEH or 8-DPAT and scanned for depigmentation before harvesting skin. MBEH exposure prompted a relative increase in stem cells among cultured melanocytes and melanoma cells, as treatment preferentially eliminated differentiated cells and spared the stem cells. Viability of this remaining, enriched stem cell population was however rapidly reduced by exposure to 8-DPAT within melanocyte and melanoma cell cultures. In human skin explants, the abundance of melanocyte stem cells was also visibly reduced after 8-DPAT treatment, in contrast to tissue exposed to MBEH. Meanwhile, significant depigmentation of the mouse pelage and loss of differentiated melanocytes was observed in vivo in response to topical application of MBEH, but not 8-DPAT. Prolonged application of the latter agent instead appeared to effectively reduce the abundance of melanocyte stem cells in the dermis. This furthers the idea that MBEH and 8-DPAT target complementary cell populations. Results indicate that combination treatment may demonstrate superior therapeutic activity by eliminating both differentiated and tumor initiating populations.

Drug development of herbomineral capsule (ALG-06) used for hypopigmentation specially in vitiligo

Many herbomineral preparations in traditional medicines are being used from time immemorial like Kushta Abrak Safaid, Busoor-e-Labinyah etc. as therapeutics remedies in common ailments such type of preparations are known to have additive and pronounced effects to cure any obstinate disease condition. The main objective of this research study is the formulation of herbomineral capsule (ALG-06) to treat such type of condition like hypopigmentation in case of vitiligo. In order to achieve the best quality of this formulation physicochemical analysis i.e. fluorescence test, ash values, extractive values and moisture content of combined powdered drug of herbs and minerals were performed followed by phytopharmaceutical calculation of flow ability of blended powder by means of angle of repose, porosity, bulk and tap density, compressibility and hausner ratio, these properties assisted to estimate the best form of powdered material filled in right size of capsule for the desired strength i.e.500mg. Accelerated stability studies were also performed to establish the efficacy of the formulation. In this regard organoleptic properties (color, odor, appearance and taste), weight variation, disintegration and bio burden of ALG-06 formulation were monitored at 40°C/75% relative humidity (RH) along with a room temperature (RT) for a period of one month.

Depigmentation caused by application of the active brightening material, rhododendrol, is related to tyrosinase activity at a certain threshold

BACKGROUND

Tyrosinase, the rate-limiting enzyme required for melanin production, has been targeted to develop active brightening/lightening materials for skin products. Unexpected depigmentation of the skin characterized with the diverse symptoms was reported in some subjects who used a tyrosinase-competitive inhibiting quasi-drug, rhododendrol.

OBJECTIVE

To investigate the mechanism underlying the depigmentation caused by rhododendrol-containing cosmetics, this study was performed.

METHODS

The mechanism above was examined using more than dozen of melanocytes derived from donors of different ethnic backgrounds. The RNAi technology was utilized to confirm the effect of tyrosinase to induce the cytotoxicity of rhododendrol and liquid chromatography-tandem mass spectrometry was introduced to detect rhododendrol and its metabolites in the presence of tyrosinase.

RESULTS

Melanocyte damage was related to tyrosinase activity at a certain threshold. Treatment with a tyrosinase-specific siRNA was shown to dramatically rescue the rhododendrol-induced melanocyte impairment. Hydroxyl-rhododendrol was detected only in melanocytes with higher tyrosinase activity. When an equivalent amount of hydroxyl-rhododendrol was administered, cell viability was almost equally suppressed even in melanocytes with lower tyrosinase activity.

CONCLUSION

The generation of a tyrosinase-catalyzed hydroxyl-metabolite is one of the causes for the diminishment of the melanocyte viability by rhododendrol.

Melanogenesis Inhibition by an Oolong Tea Extract in B16 Mouse Melanoma Cells and UV-Induced Skin Pigmentation in Brownish Guinea Pigs

To investigate the new physiological functions of oolong tea, the effects on melanogenesis were studied. An oolong tea extract inhibited melanogenesis without affecting cell growth in B16 mouse melanoma cells. However, the oolong tea extract hardly showed any inhibitory effect on mushroom tyrosinase in a cell-free system. The effects of an oolong tea extract on the intracellular tyrosinase level in B16 cells were therefore studied. All the levels of activity, protein and mRNA were decreased in the oolong tea extract-treated cells. We also investigated the inhibitory effects of oolong tea on the pigmentation induced by ultraviolet B (UVB) by using brownish guinea pigs in vivo. The number of 3,4-dihydroxyphenylalanine (DOPA)-positive melanocytes increased by UVB was repressed by an oral administration of oolong tea. These results imply that oolong tea might be effective in whitening and that its inhibitory effect on melanogenesis was involved in the decrease of intracellular tyrosinase at the mRNA level.

Melanocortin receptor accessory protein 2 (MRAP2) interplays with the zebrafish melanocortin 1 receptor (MC1R) but has no effect on its pharmacological profile

The melanocortin system is probably one of the most complex hormonal systems since it integrates agonist, encoded in the proopiomelanocortin precursor, endogenous antagonist, agouti signaling protein and agouti-related protein, five different G-protein coupled receptors and two accessory proteins. These accessory proteins interact with melanocortin receptors to allow traffic to the plasma membrane or to regulate the pharmacological profile. The MC1R fill the extension locus, which is primarily responsible for the regulation of pigmentation. In zebrafish, both MC1R and MRAP2 system are expressed in the skin. We demonstrate that zebrafish MC1R physically, or closely, interacts with the MRAP2 system, although this interaction did not result in modification of the studied pharmacological profile. However, progressive fasting induced skin darkening but also an upregulation of the MRAP2 expression in the skin, suggesting an unknown role for MRAP2a that could involve receptor desensitization processes. We also demonstrate that crowding stress induces skin darkening and a downregulation of MC1R expression in the skin.

[Experimental study on removal melanin granules from acellular dermal matrix of giant nevus]

OBJECTIVE

To study the possibility of removal melanin granules from autogenic acellular dermal matrix of giant nevus tissue by H2O2 bleaching technique.

METHODS

A total of 32 skin specimens (0.5 cm x 0.5 cm) from giant nevus tissue and 1 piece (0.5 cm x 0.5 cm) of normal skin were obtained from the surgical removal. One giant nevus tissue was chosen as control. The others and the normal skin tissue were treated with solution of 0.25% Dispase II for digestion for 24 hours under normal temperature to remove epidermis. Then each piece was immerged into solution of 0.5% Triton X-100 for digestion for 48 hours in normal temperature. One giant nevus tissue and the normal skin tissue were chosen as control. The others were immerged into solution of different concentrations of H2O2, treated under different temperature and lasting for different period. Lastly, all specimens were treated with HE staining, immunohistochemical staining, light microscopy and so on.

RESULTS

After giant nevus tissues were treated with solution of 0.25% Dispase II and immerged into solution of 0.5% Triton X-100 in normal temperature, nevus cells and all other cellular components of pigmented nevus tissues can be effectively removed, there were the cavities left by removal of cells without any residual cell debris, but still remaining part of pigment. Then each specimen were immerged into solution of different concentrations of H2O2, under different temperature and lasting for different period which can remove residual melanin granules. In solution of 3% H2O2 for 36 h under 37 degrees C, can remove all the melanin particles, the content of collagen type I in the obtained specimen was not changed. Collagen fibers were uniform in thickness, regular in arrangement with no obvious degeneration.

CONCLUSIONS

With solution of 0.25% Dispase II and solution of 0.5% Triton X-100 in normal temperature, all cells in nevus tissue can be removed effectively. Further treatment with 3% H2O2 at 37 degrees C for 36 h can remove all the melanin particles, while collagen type I has no obvious change. The preparation of acellular dermal matrix of the giant nevus may possibly be applied as autologous tissue implant to repair tissue defects.

Effect of beta-carotene supplementation on African skin

The quantification of skin carotenoid levels has a range of applications in Caucasian populations, from serving as a versatile and noninvasive biomarker (e.g., of systemic carotenoid levels, carotenoid consumption, the antioxidative capacity of skin, and oxidative stress) to being used in appearance-based interventions. Yet, no study has investigated the quantitative effect of carotenoid supplementation on African skin. The aim of this study was to determine if beta-carotene supplementation produces a significant color change in three different regions of African skin. To do so we supplemented the diet of African participants with beta-carotene over an eight-week period. Reflectance spectrophotometry measurements were taken on a weekly basis for the duration of the supplementation study. Results show a significant increase in the carotenoid coloration of lightly pigmented skin (palm of the hand) and highly pigmented skin with low sun exposure (inner arm) after supplementation. The latter was no longer significant after Bonferroni correction. The carotenoid coloration of highly pigmented skin areas with high sun exposure did not increase significantly. Skin carotenoid measurements of the palm of the hand might, therefore, serve as a potential biomarker for systemic carotenoid concentrations in people of African descent.

Dynamic monitoring of optical clearing of skin using photoacoustic microscopy and ultrasonography

Tissue optical clearing technique has shown great potential for enhancing the imaging depth and contrast of optical imaging modalities. However, the mechanism of optical clearing is still in controversy. In this manuscript, we combined photoacoustic microscopy with ultrasonography to monitor the dermic changes induced by optical clearing agents at different immersion time points. The measured parameters were correlated with the optical clearing process, and could be used to assess the optical clearing effect. Both in vitro and in vivo results demonstrated that photoacoustic microscopy and ultrasonography can potentially be used as a powerful tool in screening optical clearing agents and exploring the mechanism of optical clearing.

Comparable down-regulation of TYR, TYRP1 and TYRP2 genes and inhibition of melanogenesis by tyrostat, tocotrienol-rich fraction and tocopherol in human skin melanocytes improves skin pigmentation

BACKGROUND AND OBJECTIVE

Antioxidant has been recognized to inhibit UV-induced melanogenesis. This study aimed to elucidate the molecular mechanism of tyrostat, tocopherol and tocotrienol-rich fraction in inhibiting melanogenesis in human skin melanocytes.

MATERIALS AND METHODS

Primary culture of melanocytes was exposed to repeated doses of 0.6 J/cm2 UVA for 6 days and treated with tyrostat, tocotrienol-rich fraction or tocopherol alone or in combination.

RESULTS

UVA irradiation increased melanin content and tyrosinase activity and up-regulated TYR, TYRP1 and TYRP2 genes. Treatment with tyrostat, tocotrienol-rich fraction or tocopherol decreased melanin content and down-regulated TYR, TYRP1 and TYRP2 genes with decreased tyrosinase activity. Combined treatment exerted better effects as compared to treatment with single compound in decreasing the melanin content and down-regulating TYR, TYRP1 and TYRP2 genes. These findings indicated that tyrostat, tocotrienol-rich fraction and tocopherol inhibit melanogenesis by modulating the expression of genes involved in the regulation of melanin synthesis and inhibiting tyrosinase activity.

CONCLUSIONS

Tyrostat, tocopherol and tocotrienol-rich fraction possessed anti-melanogenic properties and might be useful in improving skin pigmentation caused by UVA exposure.

Inhibition of melanin content by Punicalagins in the super fruit pomegranate (Punica granatum)

Current efforts to develop effective skin lightening products through the inhibition of melanin production have focused on compounds that inhibit the function and activity of tyrosinase, the rate-limiting enzyme in the melanin biosynthesis pathway. Synthetic tyrosinase inhibitors, such as hydroquinone, kojic acid, and arbutin, have been reported to cause skin irritation or acute dermatitis, raising concerns about the safety of these compounds. As a result, there is a need for safe natural ingredients that show effective skin lightening. In this report, we have identified a natural ingredient, pomegranate fruit extract, that inhibits melanin production in melanocytes and shows potential for use as a cosmetic skin lightening agent. In addition, we have identified a polyphenolic compound, punicalagins, as the active melanin inhibitor in pomegranate fruit extract based on its capacity to directly inhibit melanin production.

Whitening effect of Sophora flavescens extract

CONTEXT

Sophora flavescens Ait. (Leguminosae) has been proposed as a new whitening agent for cosmetics, because it has a strong ability to inhibit tyrosinase, a key enzyme in the formation of melanin.

OBJECTIVE

We conducted a study to determine whether ethanol extract of the roots of S. flavescens has the potential for use as a whitening cosmetic agent by investigating its underlying mechanisms of action.

MATERIALS AND METHODS

To elucidate the mechanism of action of S. flavescens extract, we used DNA microarray technology. We investigated the changes in the mRNA levels of genes associated with the formation and transport of melanosomes. We also identified the formation and transport of melanosomes with immunohistochemistry and immunofluorescence analyses. Finally, the skin-whitening effect in vivo of S. flavescens extract was analyzed on human skin.

RESULTS

We found that S. flavescens extract strongly inhibited tyrosinase activity (IC50, 10.4 μg/mL). Results also showed that key proteins involved in the formation and transport of melanosomes were dramatically downregulated at both mRNA and protein level in keratinocytes exposed to S. flavescens extract. In addition, a clinical trial of a cream containing 0.05% S. flavescens extract on human skin showed it had a significant effect on skin whitening by mechanical and visual evaluation (1.14-fold).

DISCUSSION AND CONCLUSION

This study provides important clues toward understanding the effects of S. flavescens extract on the formation and transport of melanosomes. From these results, we suggest that naturally occurring S. flavescens extract might be useful as a new whitening agent in cosmetics.

Identification of sake extract as a new anti-melanogenic ingredient by in vitro and clinical trials

Overproduction of melanin is the cause of skin hyperpigmentation, which is related to several skin diseases and cosmetic concerns. Sake is a Japanese alcoholic beverage produced from rice and water by fermentation, but is little known for its effect on melanogenesis. To identify the effect of sake extract on melanin synthesis, a melanin assay was performed in melan-A murine melanocytes. Sake extract treatment significantly inhibited melanin production in a dose-dependent manner, and tyrosinase, the rate-limiting enzyme of melanogenesis, decreased significantly at the protein level. Further investigations were performed with multiple assay systems; a sake extract reduced melanin production in melan-A/SP-1 murine cell co-culture, and also in MelanoDerm, a skin equivalent model of human keratinocytes-melanocytes. Finally, subjects were treated with a formula containing the sake extract. Topical application of the sake extract product improved skin lightness (L*) significantly within 7 days. We identified sake extract as a new anti-melanogenic ingredient through in vitro and in vivo experiments. These results suggest that a sake extract can be used to improve skin hyperpigmentation.

Basic evidence for epidermal H2O2/ONOO(-)-mediated oxidation/nitration in segmental vitiligo is supported by repigmentation of skin and eyelashes after reduction of epidermal H2O2 with topical NB-UVB-activated pseudocatalase PC-KUS

Nonsegmental vitiligo (NSV) is characterized by loss of inherited skin color. The cause of the disease is still unknown despite accumulating in vivo and in vitro evidence of massive epidermal oxidative stress via H2O2 and peroxynitrite (ONOO(-)) in affected individuals. The most favored hypothesis is based on autoimmune mechanisms. Strictly segmental vitiligo (SSV) with dermatomal distribution is a rare entity, often associated with stable outcome. Recently, it was documented that this form can be associated with NSV (mixed vitiligo). We here asked the question whether ROS and possibly ONOO(-) could be players in the pathogenesis of SSV. Our in situ results demonstrate for the first time epidermal biopterin accumulation together with significantly decreased epidermal catalase, thioredoxin/thioreoxin reductase, and MSRA/MSRB expression. Moreover, we show epidermal ONOO(-) accumulation. In vivo FT-Raman spectroscopy reveals the presence of H2O2, methionine sulfoxide, and tryptophan metabolites; i.e., N-formylkynurenine and kynurenine, implying Fenton chemistry in the cascade (n=10). Validation of the basic data stems from successful repigmentation of skin and eyelashes in affected individuals, regardless of SSV or segmental vitiligo in association with NSV after reduction of epidermal H2O2 (n=5). Taken together, our contribution strongly supports H2O2/ONOO-mediated stress in the pathogenesis of SSV. Our findings offer new treatment intervention for lost skin and hair color.

Tobacco smoke-induced skin pigmentation is mediated by the aryl hydrocarbon receptor

It is widely recognized that tobacco smoke causes skin pigmentation. No studies, however, have directly evaluated the mechanisms of the changes in smoker's skin pigmentation. In this study, when cultured with water-soluble tobacco smoke extract, the human epidermal melanocytes grew to a large size and produced more melanins. We evaluated melanocyte activation by quantifying microphthalmia-associated transcription factor (MITF) expression by real-time polymerase chain reaction. MITF expression was significantly and dose-dependently increased by exposure to tobacco smoke extract. The Wnt/β-catenin signalling pathway seemed to mediate the tobacco smoke extract-induced melanocyte activation. Immunocytochemical studies revealed that the activated melanocytes actively expressed aryl hydrocarbon receptors (AhR) around the nuclear membrane. The tobacco smoke extract-induced MITF activation was inhibited by RNA silencing of the AhR. This study provides the evidence that tobacco smoke enhances pigmentation in vitro and that the increase in pigmentation may involve β-catenin- and AhR-mediated mechanisms inside human melanocytes.

Dodoviscin a inhibits melanogenesis in mouse b16-f10 melanoma cells

Nowadays, abnormal hyperpigmentation in human skin such as melasma, freckles, and chloasma has become a serious esthetic problem. Cutaneous depigmenting agents could be used to treat these hyperpigmentation-associated dieseases. Dodoviscin A is a natural product isolated from the aerial parts of Dodonaea viscosa. In the present study, we evaluated the effect of dodoviscin A on melanin production in B16-F10 melanoma cells for the first time. We found that dodoviscin A inhibited melanin biosynthesis induced by 3-isobutyl-1-methylxanthine and PD98059 significantly, and there was no obvious effect on the viability of dodoviscin A-treated B16-F10 cells. Meanwhile, dodoviscin A could suppress the activity of mushroom tyrosinase in the cell-free assay system and also decrease 3-isobutyl-1-methylxanthine-induced tyrosinase activity and expression of mature tyrosinase protein in B16-F10 cells. Western blotting analysis showed that dodoviscin A inhibited 3-isobutyl-1-methylxanthine and forskolin-induced phosphorylation of the cAMP response element binding protein in B16-F10 cells. These results indicate that dodoviscin A may be a new promising pigmentation-altering agent for cosmetic and therapeutic applications.

Atypical melanocytic naevi following melanotan injection

Melanotan is a synthetic analogue of alpha melanocyte stimulating hormone (a-MSH) that stimulates melanogenesis. It is sold on the internet and tanning salons as a quick 'tanning jab'. We report a patient who developed multiple new onset atypical naevi within one week of receiving two Melanotan injections. This case highlights the potential risk of Melanotan in stimulating dysplastic naevi or possibly malignant melanoma.