Confetti-like depigmentation from hydroquinone

Anti-melanogenic property of ginsenoside Rf from Panax ginseng via inhibition of CREB/MITF pathway in melanocytes and ex vivo human skin

Background

Ginsenosides of Panax ginseng are used to enhance skin health and beauty. The present study aimed to investigate the potential use of ginsenoside Rf (Rf) from Panax ginseng as a new anti-pigmentation agent.

Methods

The anti-melanogenic effects of Rf were explored. The transcriptional activity of the cyclic adenosine monophosphate (cAMP) response element binding protein (CREB) and the expression levels of tyrosinase, microphthalmia-associated transcription factor (MITF), and tyrosinase-related proteins (Tyrps) were evaluated in melanocytes and UV-irradiated ex vivo human skin.

Results

Rf significantly inhibited Forskolin (FSK) or UV-stimulated melanogenesis. Consistently, cellular tyrosinase activity and levels of MITF, tyrosinase, and Tyrps were downregulated. Furthermore, Rf suppressed MITF promoter activity, which was stimulated by FSK or CREB-regulated transcription coactivator 3 (CRTC3) overexpression. Increased CREB phosphorylation and protein kinase A (PKA) activity induced by FSK were also mitigated in the presence of Rf.

Conclusion

Rf can be used as a reliable anti-pigmentation agent, which has a scientifically confirmed and reproducible action mechanism, via inhibition of CREB/MITF pathway.

Glycolic Acid peels/azelaic Acid 20% cream combination and low potency triple combination lead to similar reduction in melasma severity in ethnic skin: results of a randomized controlled study

Background:

Numerous therapeutic options have been tried in the management of melasma.

Aims and Objectives:

This prospective randomized study was planned to assess the efficacy of low potency triple combination (TC) cream (TC-hydroquinone 2%/tretinoin 0.05%/fluocinolone 0.01%) versus glycolic acid (GA) peels/azelaic acid (AA) 20% cream (GA/AA) combination in melasma.

Materials and Methods:

Forty patients with melasma were recruited into this study and randomized into two groups. Group A consisting 20 patients received TC cream once a day for night time application for 3 months. Group B comprising of 20 patients received GA/AA 20% cream combination for 3 months. The disease severity was monitored with digital photography, melasma area and severity index (MASI) score, which was calculated at baseline, 6 weeks and 12 weeks, and visual analog scale (VAS) score, which was calculated at baseline and 12 weeks.

Results:

Of 40 patients, 38 were completed the study. A significant reduction in MASI and VAS was recorded after 6 weeks and 12 weeks of treatment in both groups A and B (P = 0.001). However, there was no significant difference in the mean MASI scores between the two groups at baseline, 6 weeks and 12 weeks. Similarly, there was no difference in the mean VAS scores between the two groups at baseline and 12 weeks. Four patients in group A and 3 in group B experienced adverse effects such as irritation, dryness, and photosensitivity.

Conclusion:

Both low potency TC cream and GA/AA 20% cream combination are effective in treating melasma among Indian patients.

Hydroquinone-induced depigmentation: case report and review of the literature

Melasma is an acquired cutaneous disorder caused by an overproduction of melanin by the enzyme tyrosinase. Melasma remains a therapeutic challenge and no definitive standard therapy exists. Although hydroquinone (HQ) has emerged as the most common treatment, its popularity has recently waned because of concerns about its potential carcinogenicity and manufacturing challenges. The adverse effects of HQ range from the common irritant contact dermatitis to the less frequent exogenous ochronosis (EO). Previous reports suggest that the risk of leukoderma from HQ treatment is limited to individuals of African descent. Herein, we describe for the first time the development of depigmentation and paradoxical hyperpigmentation in 2 patients with Fitzpatrick skin type III/IV after brief treatment of their melasma with the HQ-containing Nu-Derm and Reverse systems.

Idiopathic Confetti-like leukoderma with unusual presentation

Idiopathic Confetti-like leukoderma in a young Indian is illustrated, emphasizing its cardinal clinical features and histopathological findings, and its differential diagnosis is briefly outlined for instant glance.

Skin-lightening products revisited

Skin colour typology depends on the amount and location of its chromophores. Among them, eumelanins derived from 5,6-dihydroxyindole-2-carboxylic acid (DHICA) and 5,6-dihydroxyindole (DHI), and phaeomelanins are of utmost importance. These biomolecules result from the multi-step enzymatic and non-enzymatic conversion of tyrosine into melanins. Pigmentation disorders are multiple and depend on alterations in the density in active melanocytes, and on specific abnormalities of any of the complex melanogenesis mechanisms. This review presents some of the main skin-lightening agents with respect to their mechanisms of action and side-effects. Some of the novel compounds may lead to new perspectives in the fields of dermatology and cosmetology. The methods commonly used to assess efficacy of skin-lightening products rely on in vitro models including cell-free enzymatic assays, melanocyte cultures and reconstructed epidermis bioassays. Animal models have little relevance. By contrast, human testing with the support of instrumental evaluations is the most informative.

The widespread use of skin lightening creams in Senegal: a persistent public health problem in West Africa

BACKGROUND

The use of skin lightening creams is common in the female population of some African countries. The long-term use of certain products for several months to years may cause cutaneous adverse effects.

METHODS

From 1992 to 1993, we conducted an epidemiologic and clinical study in Dakar, Senegal. Women were questioned about the use of skin lightening creams and examined for potential adverse skin reactions. Six hundred and eighty-five Senegalese women participated in the study.

RESULTS

Twenty-six per cent of women were using skin lightening creams at the time and 36% had used them at some time. The most common products used were hydroquinone and corticosteroids, but 25% of women had used products of unknown composition. Seventy-five per cent of women using such creams showed cutaneous adverse effects. Facial acne was the most common adverse effect.

CONCLUSIONS

A major part of the female adult population of Senegal used skin lightening creams. The long-term use of these creams is responsible for a high rate of cutaneous adverse effects. This practice has also been reported in other countries from sub-Saharan Africa and suggests a widespread use in the African population.

The use of chemical peelings in the treatment of different cutaneous hyperpigmentations

BACKGROUND

Several chemical agents including hydroquinone, retinoic acid, and azelaic acid are currently used in the treatment of cutaneous hyperpigmentations. Recently chemical peelings with kojic acid, glycolic acid, and trichloroacetic acid, either alone or in combination, have been introduced for treatment of hyperpigmentations.

OBJECTIVE

The purpose of our study was to evaluate the efficacy of trichloroacetic acid as well as glycolic acid associated with kojic acid in the treatment of cutaneous hyperpigmentations.

METHODS

Twenty patients with diffuse melasma were treated with a solution composed of 50% glycolic acid and 10% kojic acid whereas 20 patients with localized hyperpigmentations (lentigo) were treated with 15%-25% trichloroacetic acid.

RESULTS

Complete regression of diffuse melasma was observed in 6 of 20 patients (30%), a partial regression in 12 of 20 patients (60%), and no regression in 2 of 20 patients (10%) treated with 50% glycolic acid and 10% kojic acid. Complete regression of localized hyperpigmentations was observed in 8 of 20 patients (40%), a partial regression in 10 of 20 patients (50%), and no regression in 2 of 20 patients (10%) treated with 15-25% trichloroacetic acid.

CONCLUSIONS

Based on our findings, both peelings can be considered effective in the treatment of cutaneous hyperpigmentations.

Contact allergy to kojic acid in skin care products

Kojic acid (5-hydroxy-2-(hydroxymethyl)-4-pyrone), a fungal metabolic product, has increasingly been used as a skin-depigmenting agent in skin care products marketed in Japan since 1988. In order to determine its frequency of sensitization, during 1 year from October 1992 to September 1993, we performed patch testing with it in 220 female patients with suspected cosmetic-related contact dermatitis. Of the 220 patients, 8 used at least 1 skin care product containing kojic acid, 5 of whom reacted to kojic acid as well as to 1 or more their own products containing 1% kojic acid, but not to their other products not containing it, and 3 of whom were negative to kojic acid and all their own products. Patch testing with kojic acid in the remaining group of 212 patients, who had not previously used skin care products containing it, was negative without exception. The 5 kojic-acid-sensitive patients, aged 34 to 58 years, developed facial dermatitis 1-12 months after starting application of kojic-acid-containing products. Kojic acid is considered to have high sensitizing potential, as a comparatively high frequency of contact sensitivity was observed in patients using products containing it (5 out of 8).

Hypertrophic allergic contact dermatitis from hair dye

We report a case of hypertrophic allergic contact dermatitis probably due to p-phenylenediamine (PPDA) in a 26-year-old female, which developed at the sites of application of a black hair dye to the skin. Histological examination revealed an eczematous process. The lesions subsided completely except for leukoderma that remained on the leg. Patch tests showed positive reactions to PPDA, p-aminophenol and Disperse Orange 3. PPDA, which was one of the components of the dye, was considered to be the primary sensitizer because it was the only substance able to reproduce at the patch test site both the hypertrophic pattern and the permanent leukoderma found in the patient's lesions. To explain the difference in reaction between PPDA and the other 2 para-group substances, we speculate that they are due to different quantities of reactive intermediates, oxidation products and free radicals, produced by these substances.