Tacrolimus (FK506) ointment combined with Nb-UVB could activate both hair follicle (HF) and dermal melanocyte precursors in vitiligo: the first histopathological and clinical study

Topical Tacrolimus, especially when combined with Nb-UVB, has been proven clinically to be effective in the treatment of vitiligo. However, no histological study has evaluated the repigmentation mechanism of tacrolimus ointment in combination therapy with Nb-UVB. In this study, the histological findings in patients receiving Nb-UVB were compared with those receiving topical tacrolimus combined with Nb-UVB. Twenty patients were recruited and received Nb-UVB treatment. The first ten patients were selected for the combination therapy and instructed to apply tacrolimus 0.1% ointment twice daily on the specified lesion of interest. The remaining ten patients did not receive any other topical treatments. Skin biopsy was performed at baseline from the depigmented area and 2-3 months post-treatment from the repigmented area. Biopsy specimens were stained with haematoxylin-eosin-safran (HES), Fontana Masson, HMB45, Melan A, MITF, SOX10 and Nestin. Clinically, in the combination therapy group, interfollicular repigmentation in addition to the perifollicular and marginal pattern was observed. Histologically, in the combination therapy group, besides the migration of melanocytes from the bulge of the hair follicle seen in the monotherapy group, for the first time, we observed dermal melanocyte precursors located in mid- and superficial dermis.

Administration of Apple Polyphenol Supplements for Skin Conditions in Healthy Women: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial

This clinical study was performed to evaluate the effects of continuous apple polyphenol (AP) administration on facial skin conditions and pigmentation induced by ultraviolet (UV) irradiation in healthy women participants. Participants (n = 65, age 20–39 years) were randomized to receive tablets containing AP (300 or 600 mg/day) or placebo in a double-blinded, placebo-controlled clinical trial. Continuous administration of AP for 12 weeks significantly prevented UV irradiation induced skin pigmentation (erythema value, melanin value, L value), although a dose-dependent relationship was not clearly observed. In contrast, no significant differences were detected between the groups with regard to water content and trans-epidermal water loss. Our study demonstrated that APs and their major active compounds, procyanidins, have several health benefits. Here, we report that continuous administration of AP for 12 weeks alleviated UV irradiation induced skin pigmentation, when compared with placebo, in healthy women.

Lecithin-Based Dermal Drug Delivery for Anti-Pigmentation Maize Ceramide

Ceramides have several well-known biological properties, including anti-pigmentation and anti-melanogenesis, which make them applicable for use in skincare products in cosmetics. However, the efficacy of ceramides is still limited. Dermal or transdermal drug delivery systems can enhance the anti-pigmentation properties of ceramides, although there is currently no systemic evaluation method for the efficacy of these systems. Here we prepared several types of lecithin-based emulsion of maize-derived glucosylceramide, determining PC70-ceramide (phosphatidylcholine-base) to be the safest and most effective anti-pigmentation agent using zebrafish larvae. We also demonstrated the efficacy of PC70 as a drug delivery system by showing that PC70-Nile Red (red fluorescence) promoted Nile Red accumulation in the larval bodies. In addition, PC70-ceramide suppressed melanin in mouse B16 melanoma cells compared to ceramide alone. In conclusion, we developed a lecithin-based dermal delivery method for ceramide using zebrafish larvae with implications for human clinical use.

Photoprotection and Skin Pigmentation: Melanin-Related Molecules and Some Other New Agents Obtained from Natural Sources

Direct sun exposure is one of the most aggressive factors for human skin. Sun radiation contains a range of the electromagnetic spectrum including UV light. In addition to the stratospheric ozone layer filtering the most harmful UVC, human skin contains a photoprotective pigment called melanin to protect from UVB, UVA, and blue visible light. This pigment is a redox UV-absorbing agent and functions as a shield to prevent direct UV action on the DNA of epidermal cells. In addition, melanin indirectly scavenges reactive oxygenated species (ROS) formed during the UV-inducing oxidative stress on the skin. The amounts of melanin in the skin depend on the phototype. In most phenotypes, endogenous melanin is not enough for full protection, especially in the summertime. Thus, photoprotective molecules should be added to commercial sunscreens. These molecules should show UV-absorbing capacity to complement the intrinsic photoprotection of the cutaneous natural pigment. This review deals with (a) the use of exogenous melanin or melanin-related compounds to mimic endogenous melanin and (b) the use of a number of natural compounds from plants and marine organisms that can act as UV filters and ROS scavengers. These agents have antioxidant properties, but this feature usually is associated to skin-lightening action. In contrast, good photoprotectors would be able to enhance natural cutaneous pigmentation. This review examines flavonoids, one of the main groups of these agents, as well as new promising compounds with other chemical structures recently obtained from marine organisms.

Potential adverse effect of tyrosinase inhibitors on teleosts:A review

Coloration plays a crucial role in the social communication and survival of organisms. Multidisciplinary studies have been conducted to elucidate the correlation between coloration and melanin biosynthesis (referred as melanogenesis). The multi-copper enzyme tyrosinase catalyzes the first two steps of melanogenesis for coloration in teleosts. Due to the increasing demand of tyrosinase inhibitors for the production of skin whitening cosmetics, hypopigmentation pharmaceuticals, and anti-browning agents, a large number of natural and synthetic inhibitors have been developed over the past few decades. Although a number of previous studies have focused on human use and toxicity, such as the increased cytotoxic effects of ROS-generating compounds, their ecotoxicological impacts on aquatic organisms are still poorly understood. Hence, the focus of the present review is to describe the role of coloration in teleosts as well as potential ecotoxicological effects elicited by exposure to tyrosinase inhibitors. Furthermore, this review introduces our recently registered adverse outcome pathway (AOP) related to tyrosinase inhibition and population decline in teleosts.

An Herbal H2 Blocker in Melasma Treatment

BACKGROUND

Melasma is a skin pigmentation disorder that remains resistant to available therapies. The exact cause of melasma is unknown. Histamine is an inflammatory factor. Its involvement in pigmentation is obscure. The aim of this study is to introduce an herbal antihistamine H2 receptor which is effective in these disorders.

METHODS

This is a review study by searching the electronic databases and also Persian Medicine books, from 2000 to 2018 by the keywords such as H2 antagonist, H2 blocker and melasma.

RESULTS

According to the researched studies, histamine can induce melanogenesis and melasma after a series of stages in the body. Also, Histamine, through receptors 2, triggers melasma. Therefore, it can be said that antihistamine H2 receptor can be effective in melasma. Considering chemical antihistamine, H2 receptors have side effects, such as digestive problems, H2 antagonists can be used in the treatment of diseases such as dyspepsia but they have multiple complications. On the other hand, there is an herbal H2 antagonist that can be useful for melasma due to having some special properties.

CONCLUSION

Herbal H2 blockers should be noted in melasma treatment along with the topical drugs.

Discovery of a Highly Selective MC1R Agonists Pentapeptide to Be Used as a Skin Pigmentation Enhancer and with Potential Anti-Aging Properties

One of the first lines of cutaneous defense against photoaging is (a) the synthesis of melanin and (b) the initiation of an oxidative stress response to protect skin against the harmful effects of solar radiation. Safe and selective means to stimulate epidermal pigmentation associated with oxidative stress defense are; however, scarce. Activation of the melanocortin-1 receptor (MC1R) on epidermal melanocytes represents a key step in cutaneous pigmentation initiation and, additionally, it regulates cellular defense mechanisms like oxidative stress and DNA-repair. Thus, making the activation of MC1R an attractive strategy for modulating skin pigmentation and oxidative stress. In this context, we designed and synthesized pentapeptides that act as MC1R agonists. These peptides bound, with high potency, to MC1R and activated cAMP synthesis in CHO cells expressing human MC1R. Using one lead pentapeptide, we could show that this activation of MC1R was specific as testing the activation of other G-protein coupled receptors, including the MC-receptor family, was negative. In vitro efficacy on mouse melanoma cells showed similar potency as for the synthetic MC1R agonist alpha-melanocyte stimulating hormone (NDP-alpha-MSH). Moreover, we could reproduce this activity in human skin tissue culture. The lead pentapeptide was able to induce ex-vivo protein expression of key melanogenesis markers melanocyte inducing transcription factor (MITF), tyrosinase (TYR), and tyrosinase-related protein 1 (TYRP-1). Concerning oxidative stress response, we found that the pentapeptide enhanced the activation of Nrf2 after UVA-irradiation. Our results make this pentapeptide an ideal candidate as a skin pigmentation enhancer that mimics alpha-MSH and may also have anti-photoaging effects on the skin.

Oral Polypodium Leucotomos Extract and Its Impact on Visible Light-Induced Pigmentation in Human Subjects

BACKGROUND: Visible light (VL) has multiple effects on the skin that currently available sunscreens do not protect against. Polypodium leucotomos extract (PLE) has properties that may offer protection against VL. OBJECTIVES: To determine the effectiveness of PLE in preventing VL-induced effects. METHODS: Twenty-two subjects with Fitzpatrick skin phototype IV-VI were enrolled. On day 0, subjects were irradiated with VL. Clinical Investigator’s Global Assessment (IGA) scoring and spectroscopic evaluations were performed immediately, 24 hours, and 7 days after irradiation. Subjects then received a 28-day supply of PLE (480 mg daily). Irradiation and evaluation were repeated. Three 4-mm punch biopsies were obtained for immunohistochemistry analysis: one from normal unirradiated skin and the other two twenty-four hours after irradiation, pre- and post-PLE, from sites irradiated with highest dose of VL. RESULTS: All subjects had immediate pigment darkening, persistent pigment darkening, and delayed tanning both pre- and post-PLE. For the highest VL dose (480 J/cm²) spectroscopic assessments demonstrated a statistically significant decrease in persistent pigment darkening and delayed tanning post-PLE. In addition, there was a significant decrease in cyclooxygenase-2, and a trend towards decreases in the markers for cellular damage post-PLE. While there was a trend towards lower IGA scores post-PLE, statistical significance was not reached possibly due to lack of sensitivity of the visual IGA scoring system in detecting small changes. CONCLUSIONS: Spectroscopic data and immunohistochemistry indicate an effect of PLE on visible light induced effects. As such, PLE may be used as an adjuvant to traditional means of photoprotection to protect against the effects of VL. Clinical trial registration number: NCT02904798. J Drugs Dermatol. 2019;18(12):1198-1203.

An Advanced, Physician-Strength Retinol Peel Improves Signs of Aging and Acne Across a Range of Skin Types Including Melasma and Skin of Color

Background: Facial chemical peels are highly sought after by patients with photodamage, acne, and melasma. An advanced, physician-strength superficial peel, containing 3% retinol with other firming and volumizing ingredients was developed to exfoliate, improve the appearance of fine lines and wrinkles, and plump and firm skin, while promoting a bright, even complexion. Objective: A clinical study was conducted to evaluate the tolerability, safety, and efficacy of the 3% retinol peel with a supportive homecare regimen across a range of peel candidates, females aged 18-65 years, with photodamage, acne, hyperpigmentation or melasma, and skin of color, over a series of 2-4 peels. Method: The 3% retinol peel formulation was administered under physician direction in 6-week intervals. Subjects with photodamaged skin, acne, hyperpigmentation/melasma, or skin of color (Fitzpatrick skin types IV-VI) received 2-4 peels along with a supportive homecare regimen. Dermatologist grading, self-assessment, and digital photography documented tolerability and efficacy parameters. Results: 24 subjects participated in the study with a total of 78 peels administered (Photodamage group, n=14 [with an Acne subgroup, n=5]; Melasma group, n=5; Skin of Color, n=5). The 3% retinol peel along with the homecare regimen was well tolerated under physician direction in all skin types and conditions assessed. Obvious peeling was noticeable in many subjects 3 days post-peel and resolved by day 7. In the photodamaged group, dermatologist clinical grading of fine lines, wrinkles, pore size, laxity, mottled pigmentation, lack of clarity/radiance, and overall photodamage was significantly improved (P<0.05). Benefits were observed in all groups and supported by self-assessment. Digital photography demonstrated tolerability in the days immediately post-peel, along with benefits to photodamage. Conclusion: The 3% retinol superficial peel was well tolerated and an efficacious cosmetic treatment under physician supervision in subjects of all skin types to firm skin, improve fine lines and wrinkles, and promote a bright, even complexion. J Drugs Dermatol. 2019;18(9):918-923.

Therapeutic Insights in Melasma and Hyperpigmentation Management

Melasma and postinflammatory hyperpigmentation (PIH) are the most common forms of dyschromia in patients with skin of color. Both are associated with a high psychological burden of disease. To exacerbate this burden, the need for treatment is chronic, and the results are often suboptimal in the eyes of the patient. Successful treatment is therefore contingent upon a correct diagnosis, patient education, and a carefully considered therapeutic approach. The latter is often multimodal in its design, incorporating sun protection, topical and systemic medications, and in some cases, procedural intervention. Although topical hydroquinone is a mainstay of treatment for melasma and PIH, there are alternatives that have emerged as of late that have shown varying degrees of promise, both in terms of safety and efficacy. In this article, we review the epidemiological, clinical, and histologic features of melasma and postinflammatory hyperpigmentation, and discuss important considerations for both established and emerging treatments for these vexingly common and difficult to treat conditions.

A Survey-Based Comparison of Sun Safety Practices in a Representative Cohort of the General Public Versus Attendees of a Skin Cancer Screening

A large proportion of data on photoprotective practices is yielded from free skin cancer screenings. However, the sun safety practices of populations who seek these skin cancer screenings may differ from the general public. To examine differences in skin cancer prevention practices and risk factors, we surveyed pedestrians at six locations in Washington, DC (public group, n=285) and attendees of a free skin cancer screening (screening group, n=144) using an IRB-approved survey. The screening group was older and included more individuals with fair skin than the public group. Respondents from the screening group were significantly more likely to always wear sunscreen, always seeks shade, and always or sometimes wear sun-protective clothing than the public group (P<0.05). To examine whether younger and non-white participants, who were less likely to attend our free screening, have different practices and risk factors than older and white participants, respectively, we compared survey answers for all participants by age and race. White participants were more likely to always or sometimes wear sunscreen and sun-protective clothing than non-white participants (P<0.05). Patients over 61 years were more likely to always seek shade and wear sun-protective clothing than those younger than 31 years (P<0.05). Therefore, free skin cancer screenings need to be better popularized among non-white and younger populations or more effective educational vehicles are needed. J Drugs Dermatol. 2019;18(7):649-653.

In Vitro and In Vivo Efficacy and Tolerability of a Non-Hydroquinone, Multi-Action Skin Tone Correcting Cream

Background: Pigmentation disorders are therapeutically challenging to treat, requiring complicated regimens. Objectives: Alternatives to hydroquinone (HQ) are desired. We evaluated the efficacy and tolerability of a non-HQ multi-action skin tone corrector (ETCS) developed to inhibit melanin production and improve skin quality. Design and Methods: Twice-daily use of ETCS and ETCS + AHA-Ret, a retinoid-based alpha hydroxy acid cream, was evaluated in subjects with mild to severe dyschromia. Digital images were obtained at baseline, 4, 8, and 12 weeks and included assessment of dyschromia, erythema, fine lines/wrinkles, pores, texture, and global improvement. Melanin Index (MI) measurements were obtained at baseline, 4, 8, and 12 weeks. Subject self-assessments were obtained over the course of the study. Adverse Events (AEs) were collected throughout the study. An extension study evaluated use over 16-weeks. Results: Significant mean reductions from baseline occurred in dyschromia for ETCS (n=42) and ETCS + AHA-Ret (n=10) over 12 weeks (P<0.0001, each). Significant mean reductions from baseline in MI were achieved in both groups at every timepoint (ETCS: P<0.0001; ETCS + AHA-Ret: P<0.02, 4 weeks; P<0.0001, 8 and 12 weeks). Substantial improvements were demonstrated in global improvement, fine lines/wrinkles, erythema, pores, and texture at 12 weeks. Reductions from baseline occurred in dyschromia and MI (P<0.0001, each) at 16 weeks. High levels of subject satisfaction were reported with nearly all subjects reporting reduced appearance of uneven skin tone/discoloration and lightened darker patches, and improvement in overall skin tone. Mild, transient AEs were reported with no discontinuations due to an AE. Conclusions: Twice daily use of ETCS led to early, significant reductions in dyschromia and melanin index. Combination use with a retinoid-based, AHA cream in the evening demonstrated enhanced reductions. ETCS effectively reduced hyperpigmentation, improved overall skin appearance, and was highly tolerable. J Drugs Dermatol. 2019;18(7):642-648.

Patient-Reported Outcomes in Acne Patients With Skin of Color Using Adapalene 0.3%-Benzoyl Peroxide 2.5%: A Prospective Real-World Study

Background: Patients with skin of color (SOC) and Fitzpatrick skin types (FST) IV–VI frequently develop acne. Objective: Evaluate subject-reported outcomes after treatment with adapalene 0.3%/ benzoyl peroxide 2.5% gel (0.3% A/BPO) in subjects with SOC and moderate to severe acne vulgaris. Methods: This was an open-label interventional study conducted in 3 countries (Mauritius, Singapore, and USA) in subjects of Asian, Latin-American, or black/African-American ethnicity, with an Investigator’s Global Assessment (IGA) of moderate or severe facial acne (enrollment 2:1), and FST IV to VI. For 16 weeks, subjects applied 0.3% A/BPO (once daily) and utilized a skin care regimen (oil control foam wash and oil control moisturizer SPF30). Assessments included quality of life (QoL) and subject questionnaires, IGA, Investigator’s Global Assessment of Improvement (GAI), postinflammatory hyperpigmentation (PIH; if present at baseline), and safety. Results: Fifty subjects were enrolled: 20 Asians, 17 black/African-Americans, and 13 Latin-Americans. Most had FST IV (74%) or V (22%), with moderate (70%; IGA 3) or severe (30%; IGA 4) acne. At week 16, 77% of subjects were satisfied or very satisfied with treatment, 56% of subjects had an IGA of 0 or 1 (clear/almost clear), and 87% had a good to excellent improvement in GAI. QoL improved throughout the study for all subjects; subject selection of “no effect at all” of acne on QoL increased from 16% of subjects at baseline to 55% at week 16. Of those with baseline PIH (60%), all were rated very mild to moderate. By week 16, the majority (75%) had no or very mild PIH, and the mean decrease in PIH was 27%. There were no adverse events leading to study discontinuation. Conclusion: Patients with SOC and moderate or severe facial acne reported high satisfaction with 0.3% A/BPO treatment and experienced good tolerability, improved QoL, treatment efficacy, and improvement in PIH. Clinicaltrials.gov number: NCT02932267 J Drugs Dermatol. 2019;18(6):514-520.

A chemical compound from fruit extract of Juglans mandshurica inhibits melanogenesis through p-ERK-associated MITF degradation

BACKGROUND

Trials for regulation of abnormal hyperpigmentation from the use of natural products have been going on for years. Leaf and root extracts from Juglans mandshurica are reported to function as antioxidants and to suppress allergic dermatitis. However, studies evaluating its fruit extract and the chemical compounds from the fruit extract are lacking in dermatology fields, including melanogenesis.

PURPOSE

The aim of this study is to understand the effect of the fruit extract from J. mandshurica on pigmentation and to search for specific chemical compounds that affect melanogenesis.

METHODS

After screening out any anti-melanotic effects of the fruit extract from J. mandshurica in B16F10 melanoma cells, three major phenolic compounds isolated from the fruit extract were tested by western blot analysis for expression of microphthalmia-associated transcription factor (MITF) and tyrosinase. Their effect on B16F10 melanoma cells with regard to melanogenesis was also confirmed in primary human epidermal melanocytes (PHEMs). PD98059 was tested to observe the compounds' signaling role in the extracellular signal-regulated protein kinase (ERK)-pathway.

RESULTS

Fruit extract from J. mandshurica showed anti-melanotic effects in B16F10 melanoma cells. After chemical compounds were isolated from the fruit extracts, three phenolic compounds were evaluated for anti-melanotic effects. 2-[4-(3-hydroxypropyl)-2-methoxyphenoxy]-1,3-propanediol (compound 1) showed the highest suppression effect among the three compounds. In B16F10 melanoma cells and PHEMs, reduced melanin contents were observed after treatment with the compound (1). Experiments using a blocker of ERK showed that the inhibitory effect of the compound (1) on melanogenesis was dependent on ERK-associated MITF degradation.

CONCLUSION

A chemical constituent of Juglans mandshurica Maxim. induces an inhibitory mechanism to melanogenesis. It has the potential to become a whitening agent in the medical field, though this requires further clinical investigation.

Photoaging and Photoprotection in United States Hispanic Population

Photoaging is a complex and chronic process that induces structural and functional changes in sun-exposed skin, including coarse wrinkles, laxity, dyschromia, telangiectasias, and potential precancerous lesions. Pigmented skin presents different structure and physiology that contribute to distinctive photoaging process. The skin of color population is reported to “age better” than their Caucasian counterparts in general, with fewer wrinkles and better skin texture. However, pigmentary disorders and sun-exposure related dyschromia are highly prevalent in skin of color. Hispanics are the fastest growing population in the U.S. and represents a heterogenous group of people with different skin tones and Fitzpatrick phototypes. They demonstrate large diversity and heterogeneity in skin physiology, pigmentary disorders, and photoaging-related skin color shifting. Specific concerns around hyperpigmentation, skin tone evenness, and texture or roughness are very common among Hispanics, demanding targeted medical and cosmeceutical solutions. Customized daily routines including sufficient photo-protection are essential to address such needs. This mini review identifies some of the specific skin concerns of Hispanics in America and emphasizes the needs for long-term sunscreen use and education. J Drugs Dermatol. 2019;18(3 Suppl):s121-123.

Acne and Rosacea: Special Considerations in the Treatment of Patients With Latin American Ancestry

Acne is a common disease among patients with Latin American ancestry. Its presentation is very similar to that in all skin types, but nodulocystic acne is more frequent in patients with oily and darker skin than in white Caucasians. Acne sequelae in patients with Latin American ancestry and with darker skin include postinflammatory hyperpigmentation (PIH) and atrophic and hypertrophic scars or keloids, with PIH being the most common complication affecting the quality of life of patients. Lately, more attention has been paid to rosacea in patients with darker skin. It has been seen that some of the patients, especially women, diagnosed with adult acne and who did not respond to treatment, were actually patients with rosacea. It is important to recognize the clinical characteristics of this disease in patients with darker skin in whom erythema and telangiectasia are difficult to observe. Here, we present the most relevant clinical characteristics of both diseases, as well as their treatment in patients with darker skin with Latin American ancestry. J Drugs Dermatol. 2019;18(3 Suppl):s124-126.

Disorders of Hypopigmentation

Hypopigmentation and depigmentation of the skin can be due to multiple causes and has a broad differential diagnosis. The most common cause of depigmentation worldwide is vitiligo. This disorder affects 1-2% of the world’s population and is seen in all races. Vitiligo is an autoimmune disorder in which the predominant cause is an attack by CD8+ cytotoxic T cells on melanocytes in the epidermis. This condition can have a significant negative impact on the quality of life of affected individuals. Treatment options currently include psychological counseling, topical therapy, systemic therapy, phototherapy, surgical therapy, and depigmentation. In patients with stable, refractory disease, successful repigmentation has been achieved using mini-punch grafting, blister grafting, and non-cultured epidermal suspension (NCES) grafting. Emerging therapies include the Janus kinase (JAK) inhibitors ruxolitinib and tofacitinib. Further studies exploring the pathogenesis of vitiligo are warranted in order to optimize treatment for affected patients. J Drugs Dermatol. 2019;18(3 Suppl):s115-116.

Whitening effect of L-ascorbate-2-phosphate trisodium salt on solar lentigos

Little is known about the anti-pigmenting effects of whitening agents on solar lentigos (SLs), which comprise ~ 60% of hyperpigmented facial lesions of Asian subjects. Lotions with or without 6% L-ascorbate-2-phosphate trisodium salt (APS) [test lotion (TL) and placebo lotion (PL), respectively] were applied twice daily for 24 weeks in a double-blind half-face study of 27 Japanese females with SLs on both sides of their faces. Pigmentation scores were evaluated using a photo-scale and the skin colors were assessed using a color difference meter and a mexameter for SLs and the non-lesional surrounding skin (NLS). Although the pigmentation scores were not significantly different between the TL and PL-treated SLs after 24 weeks, the L values of TL-treated SLs and NLS increased significantly with a significantly higher △L value in SLs than in NLS. In contrast, the L values of PL-treated SLs and NLS remained unchanged after the treatment. The number of subjects with > 2.0 △L was 7 of 27 (TL) and 0 of 27 (PL) in SLs and 3 of 27 (TL) and 0 of 27 (PS) in NLS. In contrast, the melanin index in TL-treated SLs and NLS significantly decreased with a significantly higher △melanin index in SLs than in NLS. Similarly, the melanin index of PL-treated SLs and NLS were significantly decreased with a significantly higher △melanin index in SLs than in NLS. These findings strongly indicate that APS has a weak but significant anti-pigmenting effect on SLs and a significant whitening effect even on normally pigmented healthy skin.

An Update on Drug-Induced Pigmentation

Drug-induced pigmentation accounts for up to 20% of all cases of acquired pigmentation. A thorough review of medical history and previous and ongoing medications as well as a complete skin examination can guide diagnosis. Implicated agents include alkylating/cytotoxic agents, analgesics, antiarrhythmics, anticoagulants, antiepileptics, antimalarials, antimicrobials, antiretrovirals, metals, prostaglandin analogs, and psychotropic agents, among others. Confirming true drug associations can be challenging, especially in the setting of delayed onset of pigmentation and coexisting polypharmacy.

[Age-related factors in the impact of chemical peeling with retinol on the functional parameters of the skin.]

Retinoids continue to be the main mean for the treatment of photoaging as they are able to align not only the various wrinkles but also to reduce skin pigmentation. Retinol serves as a reserve turned into an active substance by the cell itself in the required amount that triggers the expression of genes responsible for the development of epithelial tissue. The aim of the research therefore was to study the dynamics of the functional parameters of the skin after peeling with retinol in different age groups. 58 patients who had been treating with chemical peeling with retinol were under observation. All the patients were divided into two groups by age: the 1st group - 29 women from 30 to 45 years (38,51±4,34 years), the 2nd group - 29 women from 46 to 60 years (52,97±5,34 years). We studied the moisture content, acid-base balance, pigmentation, erythema degree, skin salinity and elasticity before treatment, 14 and 28 days after peeling. It was found that peeling with retinol bleached the skin better in the patients of the older age group, although their skin was more sensitive to the components of peeling. In the study of elasticity in the older age group, peeling with retinol reduced the extensibility, significantly increased the tone, viscosity and improved the total elasticity of the skin. Chemical peeling with retinol had the best effect on the skin in patients 46-60 years.

Biomarkers at different levels of organisation after atrazine formulation (SIPTRAN 500SC®) exposure in Rhinella schineideri (Anura: Bufonidae) Neotropical tadpoles

Brazil is an important consumer of herbicides. In sugarcane cultivation-the country's most extensive agricultural crop-atrazine-based formulations are the principal form of weed control. Several studies have investigated adverse effects of atrazine or their formulations on anurans, but not specifically on Brazilian species. Our aim was therefore to investigate the lethal and sublethal effects of an atrazine-based herbicide in Rhinella schneideri tadpoles and, in particular, effects on the pigmentation system as a new endpoint in ecotoxicological studies. Rhinella schneideri tadpoles at the Gosner-30 stage were exposed to the atrazine-based herbicide formulation, SIPTRAN 500 SC^®, in acute bioassays at concentrations of 1.5-25 mg/L. The lethal and sublethal effects induced were analysed at different ecotoxicological levels: organismal level (alterations in behaviour, growth, development, and body mass; morphologic abnormalities), histological level (liver histopathology), the pigmentation system (melanomacrophages and dermal-melanophores), and cellular level (erythrocyte micronucleus formation and other nuclear-abnormalities). This herbicide induced sublethal effects at the organismal level with alterations in swimming and growth and morphologic abnormalities. These results demonstrated that, in anuran tadpoles, the atrazine-based agrochemical increased the frequency of micronucleus formation and other nuclear-abnormalities in erythrocytes and caused liver damage. In addition, we demonstrated for the first time effects of an atrazine-based formulation on the pigmentation system of anuran tadpoles, specifically an increase in the number of melanomacrophages and dermal melanophores. This study is the first to use several widely differing endpoints at different ecotoxicological levels in a comprehensive manner for assessment of the effects of environmental stressors in order to determine the health status of Neotropical anuran species. In doing so, this study establishes a foundation for future ecological assessments.