Retinoid therapy of pigmentary disorders

Steroidogenic acute regulatory protein mediated variations of gender-specific sex neurosteroids in Alzheimer's disease: Relevance to hormonal and neuronal imbalance

The steroidogenic acute regulatory (StAR) protein mediates the rate-liming step in neuro/steroid biosynthesis. Multifaceted and delicate changes during aging, disrupting hormonal and neuronal homeostasis, constitute human senescence, an inevitable phenomenon that attributes to increased morbidity and mortality. Aging, along with progressive decreases in bioactive neurosteroids, is the primary risk factor for Alzheimer's disease (AD), which preferentially impacts two-thirds of women and one-third of men. AD is neuropathologically characterized by the accumulation of extracellular amyloid-β and intracellular phosphorylated Tau containing neurofibrillary tangles, resulting in dementia. Postmortem brains pertaining to gender-specific AD patients exhibit varied suppression of StAR and sex neurosteroid levels compared with age-matched cognitively healthy subjects, in which the attenuation of StAR is inversely correlated with the AD pathological markers. Interestingly, retinoid signaling upregulates StAR-motivated neurosteroid biosynthesis and reinstates various neurodegenerative vulnerabilities that promote AD pathogenesis. This review summarizes current understanding of StAR-driven alterations of sex neurosteroids in gender-specific AD risks and provides biochemical and molecular insights into therapeutic interventions for preventing and/or alleviating dementia for healthy aging.

Melasma Management: A Comprehensive Review of Treatment Strategies Including BTX-A

BACKGROUND

Botulinum toxin A (BTX-A) is a widely utilized protein derived from the bacterium Clostridium botulinum, known for its effectiveness in treating various medical conditions involving muscle spasticity, involuntary muscle movements, and pain disorders. Beyond its therapeutic applications, BTX-A is also commonly used in cosmetic procedures to address dynamic wrinkles, hyperhidrosis, sebum production, pore size, and overall skin texture. While the use of neurotoxins like BTX-A for treating conditions such as UVB-induced hyperpigmentation, specifically melasma, is an emerging area of interest, it is not yet a widely recognized treatment for this dermatologic condition. This literature review serves to provide a consolidated overview of the current therapeutic implications of BTX-A treatment for melasma and explore its proposed mechanisms of action.

OBJECTIVE

This review aims to provide a comprehensive analysis of the current evidence base for the efficacy of BTX-A treatment on melasma.

METHODS

To gain a comprehensive understanding on the current theories regarding BTX-A treatment on melasma, a literature review was conducted on all the available information using PubMed. A combination of keywords was used to maximize the search results, including "botulinum toxin," "melasma," "melanogenesis," "neurotoxin," "cholinergic system," "BTX-A," and "UV-induced melasma." The search was not restricted by date, allowing for the inclusion of articles offering historical context and those providing the most recent findings. Ninety-eight articles were reviewed to provide a consolidated update on the effectiveness of botulinum toxin A in reducing the appearance of melasma and potential mechanisms of action involved in doing so.

CONCLUSION

Melasma is a challenging dermatologic condition due to its chronicity and various intrinsic and extrinsic factors that influence its pathogenesis. While current treatment options for melasma include topical, oral, and light-based therapies, recent studies suggest that BTX-A may hold potential as a viable treatment modality for melasma. Despite the mechanism of action remaining unclear, it is hypothesized that BTX-A inhibition of Ach receptors on melanocytes could play a role in the reduction of melanogenesis. BTX-A treatment in melasma-affected skin demonstrates statistically significant reduction in hyperpigmented lesions associated with melasma.

Update on Melasma Treatments

Melasma is a prevalent hyperpigmentation condition known for its challenging treatment due to its resemblance to photoaged skin disorders. Numerous studies have shed light on the intricate nature of melasma, which often bears similarity to photoaging disorders. Various therapeutic approaches, encompassing topical and systemic treatments, chemical peeling, and laser therapy, have exhibited efficacy in managing melasma in previous research. However, melasma often reoccurs despite successful treatment, primarily due to its inherent photoaged properties. Given that melasma shares features with photoaging disorders, including disruptions in the basement membrane, solar elastosis, angiogenesis, and mast cell infiltration in the dermal layer, a comprehensive treatment strategy is imperative. Such an approach might involve addressing epidermal hyperpigmentation while concurrently restoring dermal components. In this article, we provide a comprehensive review of conventional treatment methods frequently employed in clinical practice, as well as innovative treatments currently under development for melasma management. Additionally, we offer an extensive overview of the pathogenesis of melasma.

Melasma: A Step-by-Step Approach Towards a Multimodal Combination Therapy

Melasma is a common challenge in the field of pigmentary skin disorders, exerting a significant emotional and psychosocial burden on patients. The persistent and recurring nature of melasma complicates its management in routine clinical practice. This comprehensive review outlines a stepwise, practical approach encompassing diagnostic, preventive and therapeutic strategies for the management of melasma. A thorough exploration of aggravating and exacerbating factors, including sun exposure, hormonal imbalances, photosensitizing medication and cosmetics, is essential for a holistic assessment of the disease. With an emphasis on consistent and effective photoprotection, initial topical treatment modalities target the melanin production and/or the transfer of melanosomes to keratinocytes. Topical tyrosine inhibitors emerge as the first choice for reducing and preventing hyperpigmentation, with compounds such as thiamidol or tranexamic acid (TXA) being preferred for their safety profile over hydroquinone (HQ), kojic acid and arbutin. Combination with chemical peels can further enhance the therapeutic efficacy, even in cases with resistant melasma. In more severe cases, laser- and light-based interventions may be considered, but with the caveat of the likelihood of recurrence within 3-6 months. Assisted TXA delivery, via either fractional non-ablative laser or microneedling techniques, can further improve clinical outcomes. In conclusion, an optimal melasma management strategy is a multimodal approach, which includes effective photoprotection and a mix of different topical treatments targeting melanin synthesis, the anti-inflammatory environment, senescence and vascularity. Complementary procedures, such as chemical peels, and laser, light-based or microneedling procedures, with or without TXA, can further expedite melanin clearance in more severely affected instances. Individual discussions with patients regarding treatment expectations, recurrence likelihood and potential side effects are paramount to a comprehensive and successful therapeutic journey.

2-Mercaptonicotinoyl glycine prevents UV-induced skin darkening and delayed tanning in healthy subjects: A randomized controlled clinical study

BACKGROUND

Chronic nonextreme sun exposure induces two mechanisms of skin pigmentation, causing immediate darkening and delayed tanning. A new molecule, 2-mercaptonicotinoyl glycine (2-MNG), has been shown in vitro to inhibit both immediate darkening and new melanin synthesis via covalent conjugation of the thiol group of 2-MNG to melanin precursors.

OBJECTIVE

To evaluate 2-MNG in preventing both mechanisms in vivo.

METHODS

In a randomized, intra-individual and controlled study, 33 subjects with melanin-rich skin were exposed to UV daylight on designated areas on the back and treated with a cosmetic formula containing 0.5% or 1% 2-MNG alone or 0.5% 2-MNG in association with lipohydroxy acid (LHA, 0.3%) plus Mexoryl-SX (MSX, 1.5%). The respective vehicles were used as controls and 4-n-butyl-resorcinol (4-n-BR, 2.5%) as a positive reference.

RESULTS

2-MNG alone significantly reduced immediate darkening and inhibited new melanin production when compared with vehicle, with higher performance at 1% than at 0.5%. 2-MNG at 0.5% in association with LHA and MSX showed significantly higher performance than 2-MNG 0.5% alone. 2-MNG at 0.5% and 1% showed significantly better performance than 4-n-BR.

CONCLUSIONS

2-MNG inhibited both UV-induced skin pigmentation mechanisms in vivo. The association of 2-MNG with LHA plus MSX showed the highest efficacy on melanin-rich skin with pigmentation induced by UV exposure.

Different therapeutic approaches in melasma: advances and limitations

Melasma is a chronic hyperpigmentation skin disorder that is more common in the female gender. Although melasma is a multifactorial skin disorder, however, sun-exposure and genetic predisposition are considered as the main etiologic factors in melasma occurrence. Although numerous topical and systemic therapeutic agents and also non-pharmacologic procedural treatments have been considered in melasma management, however, the commonly available therapeutic options have several limitations including the lack of sufficient clinical effectiveness, risk of relapse, and high rate of unwanted adverse drug reactions. Recruitment of nanotechnology for topical drug delivery in melasma management can lead to enhanced skin penetration, targeted drug delivery to the site of action, longer deposition at the targeted area, and limit systemic absorption and therefore systemic availability and adverse drug reactions. In the current review, first of all, the etiology, pathophysiology, and severity classification of melasma have been considered. Then, various pharmacologic and procedural therapeutic options in melasma treatment have been discussed. Afterward, the usage of various types of nanoparticles for the purpose of topical drug delivery for melasma management was considered. In the end, numerous clinical studies and controlled clinical trials on the assessment of the effectiveness of these novel topical formulations in melasma management are summarized.

Management of Melasma: Laser and Other Therapies-Review Study

Melasma is a commonly occurring pigmented skin condition that can significantly affect one's appearance, described as symmetric hyperpigmentation that presents as irregular brown to gray-brown macules on various facial areas, such as the cheeks, forehead, nasal bridge, and upper lip, along with the mandible and upper arms. Due to its complex pathogenesis and recurrent nature, melasma management is challenging and the outcomes following treatment are not always deemed satisfactory. Solely treating hyperpigmentation may prove ineffective unless paired with regenerative techniques and photoprotection, since one of the main reasons for recurrence is sun exposure. Hence, the treatment protocol starts with addressing risk factors, implementing stringent UV protection, and then treatment using different strategies, like applying topical treatments, employing chemical peels, laser and light therapies, microneedling, and systemic therapy. This review aims to provide a summary of the effectiveness and safety of the frequently employed laser and light therapies for treating melasma, focusing on laser therapy as a treatment for melasma.

Recent Trends in the Management of Acne Vulgaris: A Review Focusing on Clinical Studies in the Last Decade

Acne vulgaris is a prevalent chronic inflammatory skin condition with significant implications for quality of life, particularly among adolescents and young adults. Recent advancements in understanding its pathophysiology and developing novel therapeutic modalities have reshaped the landscape of acne management. This review provides an overview of recent trends in acne management, focusing on clinical studies conducted in the past decade. Key findings include insights into acne pathogenesis, emerging treatment modalities, comparative effectiveness of traditional and emerging therapies, and considerations for patient-centered care. The review underscores the importance of staying updated with recent clinical studies to provide evidence-based care and optimize patient treatment outcomes. Moreover, it highlights the need for continued research efforts to develop personalized treatment approaches, explore combination therapies, and address the psychosocial impact of acne. Collaborative endeavors between clinicians and researchers are essential to advance the field of acne management and improve patient outcomes.

Nanocosmeceuticals: Trends and Recent Advancements in Self Care

The term cosmetics refers to any substances or products intended for external application on the skin with the aim of protection and better appearance of the skin surface. The skin delivery system promotes the controlled and targeted delivery of active ingredients. The development of this system has been driven by challenges encountered with conventional cosmeceuticals, including low skin retention of active components, limited percutaneous penetration, poor water dispersion of insoluble active ingredients, and instability of effective components. The aim is to create cosmeceuticals that can effectively overcome these issues. This review focuses on various nanocarriers used in cosmeceuticals currently and their applications in skin care, hair care, oral care, and more. The importance of nanotechnology in the sphere of research and development is growing. It provides solutions to various problems faced by conventional technologies, methods, and product formulations thus taking hold of the cosmetic industry as well. Nowadays, consumers are investing in cosmetics only for better appearance thus problems like wrinkles, ageing, hair loss, and dandruff requires to be answered proficiently. Nanocarriers not only enhance the efficacy of cosmeceutical products, providing better and longer-lasting effects, but they also contribute to the improved aesthetic appearance of the products. This dual benefit not only enhances the final quality and efficacy of the product but also increases consumer satisfaction. Additionally, nanocarriers offer protection against UV rays, further adding to the overall benefits of the cosmeceutical product. Figure 1 represents various advantages of nanocarriers used in cosmeceuticals. Nanotechnology is also gaining importance due to their high penetration of actives in the deeper layers of skin. It can be said that nanotechnology is taking over all the drawbacks of the traditional products. Thus, nanocarriers discussed in this review are used in nanotechnology to deliver the active ingredient of the cosmeceutical product to the desired site.

Clinical Assessment, Diagnosis, and Management of Infraorbital Wrinkles and Pigmentation

Lower eyelid skin is unique and different from that of other areas. In addition to being an area of high exposure to the sun and elements, there are anatomic considerations and specific histologic characteristics that can cause the skin in this area to be more sensitive. These attributes can readily cause under-eye wrinkling and pigmentation. This review aims to present an updated overview of the current knowledge regarding the clinical characteristics, diagnosis, and management of wrinkles and pigmentation in this area. These disorders are usually caused by different factors, such as genetics, aging, sun exposure, lack of sleep, and stress.

Human Skin Aging and the Anti-Aging Properties of Retinol

The skin is the most-extensive and -abundant tissue in the human body. Like many organs, as we age, human skin experiences gradual atrophy in both the epidermis and dermis. This can be primarily attributed to the diminishing population of epidermal stem cells and the reduction in collagen, which is the primary structural protein in the human body. The alterations occurring in the epidermis and dermis due to the aging process result in disruptions to the structure and functionality of the skin. This creates a microenvironment conducive to age-related skin conditions such as a compromised skin barrier, slowed wound healing, and the onset of skin cancer. This review emphasizes the recent molecular discoveries related to skin aging and evaluates preventive approaches, such as the use of topical retinoids. Topical retinoids have demonstrated promise in enhancing skin texture, diminishing fine lines, and augmenting the thickness of both the epidermal and dermal layers.

Environmentally friendly stability-indicating HPLC method for the determination of isotretinoin in commercial products and solubility samples

In this study, an environmentally friendly "high-performance liquid chromatography (HPLC)" assay to quantify isotretinoin (ITN) in commercial products and solubility samples is designed and verified. A Nucleodur reverse-phase C18 column was used as the stationary phase to identify ITN. The ecologically friendly mobile phase was composed of ethyl acetate and ethanol (50:50 v/v), and it was delivered at a flow rate of 1.0 mL/min. ITN was measured at 354 nm in wavelength. The current HPLC method had a determination coefficient of 0.9994 and was linear in the 0.2-80 μg/g range. The current protocol for ITN measurement was also rapid (retention time = 2.78 min), accurate (%recoveries = 98.60-101.52), precise (% uncertainties = 0.71-0.98), and sensitive. According to the AGREE methodology, the current procedure received an outstanding greenness profile with an AGREE score of 0.76. By determining ITN in commercial products and solubility samples, the applicability of the current approach was proven. ITN was discovered to be present in 98.43% and 100.84%, respectively, of commercial capsule brands A and B. The ITN's solubility in numerous eco-friendly solvents was successfully measured. Under different stress conditions, the current approach was able to distinguish between its degradation products, demonstrating its stability-indicating characteristics. These findings indicated that ITN in procured capsules and solubility samples might be regularly tested by the suggested approach.

Antioxidants for improved skin appearance: Intracellular mechanism, challenges and future strategies

Recent advances in molecular and biochemical processes relevant to the skincare field have led to the development of novel ingredients based on antioxidants that can improve skin health and youthfulness. Considering the plethora of such antioxidants and the many implications for the skin's appearance, this review focuses on describing the critical aspects of antioxidants, including cosmetic functions, intracellular mechanisms and challenges. In particular, specialized substances are suggested for the treatment of each skin condition, such as skin ageing, skin dehydration and skin hyperpigmentation, which treatments can maximize effectiveness and avoid side effects during skin care processes. In addition, this review proposes advanced strategies that either already exists in the cosmetic market or should be developed to improve and optimize cosmetic' beneficial effects.

Hydroquinone cream-based polymer microneedle roller for the combined treatment of large-area chloasma

Melasma is a common hyperpigmented skin condition that occurs on the face and other areas prone to light exposure, seriously affecting people's quality of life. Microneedle, a new type of transdermal drug delivery device, can significantly improve skin permeability. In this study, we designed and fabricated a polymer microneedle roller (PMR) using a mold hot pressing method, and established a mouse model of melasma induced by ultraviolet radiation. The dynamometer and insertion test of MNs into parafilm and skin of mice indicates that the MNs have sufficient mechanical properties to insert parafilm and skin of mice. The two methods (apply hydroquinone cream (HQC) directly and pre-treat with PMR before applying HQC) were used to treat melasma. From the results of skin surface observation, determination of superoxide dismutase (SOD) activity and malondialdehyde (MDA) content in skin and liver tissues, histological observation, and skin Optical coherence tomography (OCT), we confirmed both the two methods had a therapeutic effect while the PMR pretreatment group exhibited a better therapeutic effect. In addition, there were statistical differences between the UV group (P < 0.05). Together these results indicated that the MNs may be promising in future clinical applications in improving the UV irradiation-induced pigmentation like melisma.

Disorders of hyperpigmentation. Part II. Review of management and treatment options for hyperpigmentation

Key challenges in the management of pigmentary disorders such as melasma and postinflammatory hyperpigmentation are their resistance to treatment, tendency to recur after treatment, and the risk of exacerbating hyperpigmentation with many treatment modalities. The second article in this 2-part continuing medical education series on pigmentary disorders focuses on the evidence behind medical and procedural treatments of dyschromias, including photoprotection, topical lightening agents, oral agents, chemical peels, and laser therapy.

Perspectives of topical formulations for melasma

Melasma is acquired hyperpigmentation that mainly affects the face, can cause negative changes in self-esteem, and mostly affects women. Treatment is difficult, and different drugs can be used in mono or combination therapy. In this article, we present a brief overview of melasma, how to evaluate it, and a synthesis of the most commonly used topical therapies and their indications, including sunscreens, pharmacological agents, and plant extracts. Hydroquinone (4%) in monotherapy or combined with corticosteroids (dexamethasone and fluocinolone acetonide) and retinoids (tretinoin); arbutin (1%); methimazole (5%); kojic (2%), azelaic (20%), and tranexamic (5%) acids are the pharmacological agents that stand out. Correct application of these substances determines a variable improvement in melasma but often causes adverse reactions such as erythema, itching, and burning at the application site. Vitamin C can contribute to the reduction of melasma and have little or no adverse effects while sunscreens are normally used as coadjuvant therapies. In conclusion, we have compiled specific topical therapies for treating melasma and discussed those that are the most used currently. We consider it important that prescribers and researchers evaluate the best cost-benefit ratio of topical therapeutic options and develop new formulations, enabling efficacy in the treatment with safety and comfort during application, through the reduction of adverse effects.

Bioanalysis of Endogenous Isotretinoin in Altered and Unaltered Human Plasma by Liquid Chromatography-Tandem Mass Spectrometry Coupled with Electrospray Ionization

Bioanalytical method development and validation of endogenous Isotretinoin with Isotretinoin D5 as internal standard was done as per current regulatory guidelines. The method is simple, rugged and sensitive enough to estimate endogenous Isotretinoin using the chromatography-tandem mass spectrometry technique. An alternative approach has been adopted for quantitative analysis of endogenous Isotretinoin in human plasma. Isotretinoin free matrix (surrogate matrix) was prepared and further used for the development and validation of Isotretinoin. The method was validated in altered and unaltered plasma. The chromatographic optimization was done with column (ACE C18, 100 × 4.6 mm I.D. 5 μm particle size), using a mobile phase containing 1 mM ammonium acetate, pH 3.0 as a solvent A and solvent B (1 mM ammonium acetate (pH 3.0) with acetonitrile in a ratio of 10:90). A flow rate was set at 0.75 mL/min in a binary gradient mode. The analyte was recovered by liquid-liquid extraction method with diethyl ether as an extraction solvent. Multi-reaction monitoring mode in negative polarity was implemented for the quantification of endogenous Isotretinoin in plasma. The calibration curve of Isotretinoin was linear (r2 > 0.9992) over the concentration range of 0.5-1000 ng/mL. The intra-day precision was found in a range of 2.0-3.9% CV for altered samples and 0.9-3.7% CV for unaltered samples. The inter-day precision was found 2.6-6.1% CV for altered samples and 1.3-3.8% CV for unaltered samples. The average recovery of the extraction procedure was found 64.6% for altered samples and 62.2% for unaltered samples.

Understanding Melasma-How Can Pharmacology and Cosmetology Procedures and Prevention Help to Achieve Optimal Treatment Results? A Narrative Review

Melasma is a chronic skin condition that involves the overproduction of melanin in areas exposed to ultraviolet radiation. Melasma treatment is long-term and complicated with recurrence and resistance to treatment. The pathogenesis of melasma is highly complex with multiple pathologies occurring outside of the skin pigment cells. It includes photoaging, excessive melanogenesis, an increased number of mast cells, increased vascularization, and basement membrane damage. In addition, skin lesions related to melasma and their surrounding skin have nearly 300 genes differentially expressed from healthy skin. Traditionally, melasma was treated with topical agents, including hydroquinone, tretinoin, glucocorticosteroids and various formulations; however, the current approach includes the topical application of a variety of substances, chemical peels, laser and light treatments, mesotherapy, microneedling and/or the use of systemic therapy. The treatment plan for patients with melasma begins with the elimination of risk factors, strict protection against ultraviolet radiation, and the topical use of lightening agents. Hyperpigmentation treatment alone can be ineffective unless combined with regenerative methods and photoprotection. In this review, we show that in-depth knowledge associated with proper communication and the establishment of a relationship with the patient help to achieve good adherence and compliance in this long-term, time-consuming and difficult procedure.

Medical therapies for Melasma

Melasma is a common malady affecting all races with a higher incidence in Hispanics, Middle Eastern, Asians and African origin females (Fitzpatrick skin phototypes III-V). Women are affected much more often than men. Melasma remains a significant cause of cosmetic morbidity and psychosocial embarrassment affecting quality of life necessitating effective and reliable treatment. Unfortunately, treatment remains unsatisfactory due to limited efficacy, adverse effects and relapses after stopping treatment. Although chemical peels, laser and light therapies and dermabrasion may have utility, the evidence available for their efficacy is limited and they often cause post inflammatory hyperpigmentation particularly in individuals with darker skin types. Medical therapies remain mainstay in the management of melasma. The triple combination, hydroquinone 4%, tretinoin 0.05% and fluocinolone acetonide 0.01% (Triluma, Galderma, Ft. Worth Texas, often modified incorporating different corticosteroids) remains the only US FDA approved treatment for melasma and is the gold standard due its demonstrated efficacy across ethnicities. Oral tranexamic acid alone or in combination with other modalities has also shown significant efficacy. Several cosmeceuticals and botanical extracts used as skin lightening agents have been demonstrated to be useful. Physical sunscreens containing zinc oxide, iron oxide, titanium dioxide, and silicones provide photoprotective and camouflage effect. We propose that a multimodality approach to the treatment of melasma is the most effective treatment approach. This review is focused on the medical therapies for melasma.

Multidirectional activity of bakuchiol against cellular mechanisms of facial aging - Experimental evidence for a holistic treatment approach

Objective

Skin ageing is a multifactorial process involving formation of reactive oxygen species, consecutive inflammation with reduced epidermal and dermal cell viability and resulting damage to the extracellular matrix. Effective dermocosmetic treatment modalities should ideally address these hallmarks in a holistic approach. Here, we determined the corresponding activity profile of bakuchiol, a plant‐derived meroterpene, in an array of in vitro, ex vivo and in vivo studies and compared it to retinol, currently considered as gold standard in topical antiageing cosmetics.

Methods

The antioxidative capacity and power of bakuchiol and retinol were analysed by measuring 2,2′‐diphenyl‐1‐picrylhydrazyl (DPPH) reduction via its absorption decay and electron spin resonance spectroscopy, respectively. Effects on prostaglandin E2 (PGE2), macrophage migration inhibitory factor (MIF), fibroblast growth factor 7 (FGF7), collagen type I and VII (COL1A1, COL7A1), fibronectin (FN) levels as well as the metabolization of water‐soluble tetrazolium 1 (WST‐1) were determined in human dermal fibroblasts. Epidermal regeneration was assessed utilizing an in vitro wound healing model. FN protein levels were analysed ex vivo after treatment with a formulation containing bakuchiol, retinol or vehicle using suction blister fluid. Skin condition improvement was determined in vivo in a split‐face comparison study after application of bakuchiol or vehicle.

Results

In contrast to retinol, bakuchiol demonstrated high antioxidative efficacy. Levels of PGE2 and MIF were significantly decreased by both bakuchiol and retinol. Bakuchiol but not retinol significantly increased FGF7 protein levels. WST‐1 metabolization levels were significantly augmented by bakuchiol and retinol. Bakuchiol and retinol application led to a significant augmentation of COL1A1, COL7A1 and FN protein levels. Wounds supplemented with bakuchiol but not retinol displayed a significant increase in epidermis regeneration. Clinically, areas treated with a bakuchiol‐containing formulation showed a statistically significant increase in FN protein values after a 4‐week application compared to untreated areas and areas treated with vehicle.

Conclusion

These data provide evidence for the multidirectional efficacy of bakuchiol against cellular hallmarks of skin ageing. Its activity profile shares some common features with retinol but demonstrates several hitherto unknown biopositive effects in our studies, namely stimulation of the critical extracellular matrix component FN, and accelerated epidermal regeneration and wound healing.

Bilateral periareolar hyperpigmentation after augmentation mammoplasty: a case report and literature review

Complications arising from breast augmentation procedures are broadly categorized as either surgery-related or prosthesis-related. Many reports have described complications associated with breast augmentation. However, to date, periareolar post-inflammatory hyperpigmentation (PIH) after breast augmentation has not been reported. Herein, we report a case of PIH after augmentation mammoplasty using a silicone implant through the periareolar approach. A 35-year-old woman, who underwent bilateral breast augmentation using a periareolar approach, presented with bilateral periareolar tissue changes, with dark brown, irregular macules appearing 6 weeks postoperatively. Based on clinical symptoms and histological examination, the lesion was diagnosed as PIH. Topical hydroquinone and retinoic acid were applied for 8 weeks after the pigmentation appeared. After 6 months of observation, the pigmentation faded. To summarize, we report a case of pigmentation around the bilateral nipples after periareolar breast augmentation along with a literature review.

Naphthalene Exchange in [Re(η6 -napht)2 ]+ with Pharmaceuticals Leads to Highly Functionalized Sandwich Complexes [M(η6 -pharm)2 ]+ (M=Re/99m Tc)

Bis-arene sandwich complexes are generally prepared by the Fischer-Hafner reaction, which conditions are incompatible with most O- and N- functional groups. We report a new way for the synthesis of sandwich type complexes [Re(η6 -arene)2 ]+ and [Re(η6 -arene)(η6 -benzene)]+ from [Re(η6 -napht)2 ]+ and [Re(η6 -napht)(η6 -benzene)]+ , with functionalized arenes and pharmaceuticals. N-methylpyrrolidine (NMP) facilitates the substitution of naphthalene with the incoming arene. A series of fully characterized rhenium sandwich complexes with simple arenes, such as aniline, as well as with active compounds like lidocaine and melatonin are presented. With these rhenium compounds in hand, the radioactive sandwich complexes [99m Tc(η6 -pharm)2 ]+ (pharm=pharmaceutical) can be unambiguously confirmed. The direct labelling of pharmaceuticals with 99m Tc through η6 -coordination to phenyl rings and the confirmation of the structures with the rhenium homologues opens a path into molecular theranostics.

Management of periorbital hyperpigmentation: An overview of nature-based agents and alternative approaches

Periorbital hyperpigmentation (POH) is a common dermatological condition that presents as dark periorbital area beneath the lower eyelids, and it is commonly found in females belonging to the age group of 16 to 45 years. The data presented in this review include studies conducted on patients with a clinical/histological diagnosis of POH or melasma. Many diverse topical depigmenting agents comprising an array of naturally obtained actives such as arabinoxylans, α-arbutin, asiaticoside, azelaic acid, beta-carotene, boswellic acid, caffeine, chrysin, curcumin, cyanidin-3-glucoside, d-glucoronic acid, dihydrochalcone, dipalmitoyl-hydroxyprolene, fucoxanthin, genistein, glabridin, b-glucogallin, hyaluronic acid, lactic acid, lycopene, niacinamide, pycnogenol, retinol, salidroside, and xymenynic acid demonstrated significant benefits in the management of POH. An exhaustive literature search revealed that other techniques such as blepharoplasty, carboxytherapy, calcium hydroxylapatite fillers, tear trough implant, Q-switched ruby laser, medicated tattoo, fat transfer, micro-needling, chemical peels, nitrogen plasma skin regeneration, intense pulsed light, and radiofrequency have been evaluated and reported to be beneficial in the treatment of POH. The use of topical depigmenting agents is the most widely reported method in the clinical management of POH. Of these, α-arbutin, caffeine, cyanidin-3-glucoside, and dihydrochalcone are reported to exhibit significant benefits. Combination products containing a blend of actives are reported to be better than single active containing products. This review aims to provide a comprehensive perspective on the role of several topical actives in the modulation of melanin and tyrosinase biosynthesis pathway involved in the complex pathophysiology of POH. It also presents the advantages of combination products and other alternative therapies used in the management of POH.

Melasma Treatment: An Evidence-Based Review

BACKGROUND

Melasma is an acquired, chronic pigmentary disorder predominantly affecting women. It may significantly affect quality of life and self-esteem due to its disfiguring appearance. Multiple treatments for melasma are available, with mixed results.

OBJECTIVE

The aim of this article was to conduct an evidence-based review of all available interventions for melasma.

METHODS

A systematic literature search of the PubMed electronic database was performed using the keywords 'melasma' and/or 'chloasma' in the title, through October 2018. The search was then limited to 'randomized controlled trial' and 'controlled clinical trial' in English-language journals. The Cochrane database was also searched for systematic reviews.

RESULTS

The electronic search yielded a total of 212 citations. Overall, 113 studies met the inclusion criteria and were included in this review, with a total of 6897 participants. Interventions included topical agents, chemical peels, laser- and light-based devices, and oral agents. Triple combination cream (hydroquinone, tretinoin, and corticosteroid) remains the most effective treatment for melasma, as well as hydroquinone alone. Chemical peels and laser- and light-based devices have mixed results. Oral tranexamic acid is a promising new treatment for moderate and severe recurrent melasma. Adverse events from all treatments tend to be mild, and mainly consist of skin irritation, dryness, burning, erythema, and post-inflammatory hyperpigmentation.

CONCLUSIONS

Hydroquinone monotherapy and triple combination cream are the most effective and well-studied treatments for melasma, whereas chemical peels and laser- and light-based therapies are equal or inferior to topicals, but offer a higher risk of adverse effects. Oral tranexamic acid may be a safe, systemic adjunctive treatment for melasma, but more studies are needed to determine its long-term safety and efficacy. Limitations of the current evidence are heterogeneity of study design, small sample size, and lack of long-term follow-up, highlighting the need for larger, more rigorous studies in the treatment of this recalcitrant disorder.

Complementary effect of hydroquinone and retinoic acid on corneocyte desquamation with their combination use

BACKGROUND

Retinoic acid (RA) enhances skin-lightening capabilities of hydroquinone (HQ), at least in part, by facilitating desquamation which leads to increase penetration of HQ. The desquamation also affects skin irritation levels. The mechanism of RA-induced desquamation, however, has not been completely explored and no such data has been available for HQ uses.

OBJECTIVE

To examine the role of HQ, RA, and their combination in the desquamation.

METHODS

Primary cultured normal human keratinocytes, which were treated with HQ and/or RA in presence or absence of serine-specific inhibitor Kazal type5 (SPINK5)/lympho-epithelial Kazal-type-related inhibitor (LEKTI) knockdown or recombinant human SPINK5/LEKTI, and biopsied skin samples applied with HQ or RA were examined. Expression levels of corneodesmosin (CDSN), desmocollin1 (DSC1), kallikrein5 (KLK5), KLK7, and SPINK5/LEKTI, and proteolysis activity against extracted human skin epidermal protein were determined using time-course real-time PCR, Western blotting, ELISA, and immunofluorescence staining.

RESULTS

HQ increased but RA decreased the synthesis of CDSN and DSC1. HQ reduced corneodesmosome degradation by the upregulation of SPINK5/LEKTI, whereas RA showed opposite results without upregulation of SPINK5/LEKTI. The combination of HQ and RA was close to the sum of the individual components.

CONCLUSIONS

HQ reduced corneocyte desquamation. However, RA enhanced desquamation. The combination induced more desquamation than HQ but less than RA.

Role of the steroidogenic acute regulatory protein in health and disease

Steroid hormones are an important class of regulatory molecules that are synthesized in steroidogenic cells of the adrenal, ovary, testis, placenta, brain, and skin, and influence a spectrum of developmental and physiological processes. The steroidogenic acute regulatory protein (STAR) predominantly mediates the rate-limiting step in steroid biosynthesis, i.e., the transport of the substrate of all steroid hormones, cholesterol, from the outer to the inner mitochondrial membrane. At the inner membrane, cytochrome P450 cholesterol side chain cleavage enzyme cleaves the cholesterol side chain to form the first steroid, pregnenolone, which is converted by a series of enzymes to various steroid hormones in specific tissues. Both basic and clinical evidence have demonstrated the crucial involvement of the STAR protein in the regulation of steroid biosynthesis. Multiple levels of regulation impinge on STAR action. Recent findings demonstrate that hormone-sensitive lipase, through its action on the hydrolysis of cholesteryl esters, plays an important role in regulating STAR expression and steroidogenesis which involve the liver X receptor pathway. Activation of the latter influences macrophage cholesterol efflux that is a key process in the prevention of atherosclerotic cardiovascular disease. Appropriate regulation of steroid hormones is vital for proper functioning of many important biological activities, which are also paramount for geriatric populations to live longer and healthier. This review summarizes the current level of understanding on tissue-specific and hormone-induced regulation of STAR expression and steroidogenesis, and provides insights into a number of cholesterol and/or steroid coupled physiological and pathophysiological consequences.

On the role of skin in the regulation of local and systemic steroidogenic activities

The mammalian skin is a heterogeneous organ/tissue covering our body, showing regional variations and endowed with neuroendocrine activities. The latter is represented by its ability to produce and respond to neurotransmitters, neuropeptides, hormones and neurohormones, of which expression and phenotypic activities can be modified by ultraviolet radiation, chemical and physical factors, as well as by cytokines. The neuroendocrine contribution to the responses of skin to stress is served, in part, by local synthesis of all elements of the hypothalamo-pituitary-adrenal axis. Skin with subcutis can also be classified as a steroidogenic tissue because it expresses the enzyme, CYP11A1, which initiates steroid synthesis by converting cholesterol to pregnenolone, as in other steroidogenic tissues. Pregnenolone, or steroidal precursors from the circulation, are further transformed in the skin to corticosteroids or sex hormones. Furthermore, in the skin CYP11A1 acts on 7-dehydrocholesterol with production of 7-dehydropregnolone, which can be further metabolized to other Δ7steroids, which after exposure to UVB undergo photochemical transformation to vitamin D like compounds with a short side chain. Vitamin D and lumisterol, produced in the skin after exposure to UVB, are also metabolized by CYP11A1 to several hydroxyderivatives. Vitamin D hydroxyderivatives generated by action of CYP11A1 are biologically active and are subject to further hydroxylations by CYP27B1, CYP27A1 and CP24A. Establishment of which intermediates are produced in the epidermis in vivo and whether they circulate on the systemic level represent a future research challenge. In summary, skin is a neuroendocrine organ endowed with steroid/secosteroidogenic activities.

Facial primer provides immediate and long-term improvements in mild-to-moderate facial hyperpigmentation and fine lines associated with photoaging

BACKGROUND

Photoaged skin results from various environmental factors, most importantly chronic sun exposure. Dyschromia and fine lines/wrinkles are common clinical manifestations of photodamaged skin.

PURPOSE

This single-center clinical trial was conducted to assess the efficacy and tolerability of a new multifunctional facial primer (camouflage, broad-spectrum SPF 50, and a treatment for hyperpigmentation) when used by females with mild-to-moderate facial hyperpigmentation and fine lines due to photoaging over a course of 12 weeks.

PATIENTS AND METHODS

Subjects were provided test material (Even Up-Clinical Pigment Perfector) and supporting products to use on their face and neck. Products were used according to specific application instructions. Clinical grading for efficacy and tolerability assessments were performed by an expert grader at baseline, baseline (post-application primer), week 4, week 8, week 12, and week 12 (post-application primer). Standardized digital photographs were taken, and self-assessment questionnaires were conducted.

RESULTS

Twenty-eight female subjects completed the 12-week trial. The facial primer improved scores for the appearance of hyperpigmentation and other photoaging parameters immediately after the first application. The treatment also showed a progressive improvement in the clinical assessment of hyperpigmentation and other photoaging parameters over the 12-week trial. These long-term benefits can be attributed to an improvement in the underlying skin condition. The facial primer was well tolerated. Subject questionnaires showed that the product was highly rated at all visits.

CONCLUSION

The facial primer was shown to be effective and well tolerated for immediate and long-term improvement in the appearance of mild-to-moderate hyperpigmentation and fine lines associated with photodamage when used over a 12-week period.

An integral topical gel for cellulite reduction: results from a double-blind, randomized, placebo-controlled evaluation of efficacy

BACKGROUND

Cellulite is a serious cosmetic concern for most of the 90% of women affected by it.

OBJECTIVE

To assess the clinical efficacy of a complex integral anti-cellulite gel.

METHODS

This double-blind, randomized, placebo-controlled study involved 44 healthy women, aged 25-55 years. Subjects had a normal to slightly overweight body mass index and presented slight to moderate cellulite on their thighs, buttocks, and/or hips at baseline. Subjects were randomly assigned to either the treated or placebo group and accordingly applied the active product or placebo on their hips, stomach, buttocks, and thighs, twice daily for 3 months. Skin tonicity, orange-peel aspect, and stubborn cellulite were assessed at day 0, 28, 56, and 84. A self-evaluation questionnaire was completed by all volunteers.

RESULTS

At the end of the study, an average of 81% of the subjects applying the active product presented improvement in their cellulite condition versus 32% for the placebo group (all descriptors and sites combined). At day 84, skin tonicity, orange-peel appearance, and stubborn cellulite were improved in a significant manner (P<0.05) over placebo, on all studied areas. Skin tonicity improved on average by +41% for buttocks, +35% for hips, and +31% for thighs. Orange peel appearance was reduced on average by -25% for buttocks, -22% for hips, and -22% for thighs. Stubborn cellulite was reduced on average by -19% for buttocks, -24% for hips, and -22% for thighs. Circumference measurements decreased in a significant manner (P<0.05) over placebo, for the abdomen (average value of -1.1 cm) and thighs (average value of -0.8 cm). The product was well tolerated and perceived by the volunteers themselves as better performing than placebo on all criteria.

CONCLUSION

All results validate the efficacy of the present integral formulation to significantly reduce signs of cellulite and reshape the silhouette.

Treatment of melasma with topical agents, peels and lasers: an evidence-based review

BACKGROUND

Melasma is an acquired disorder of hyperpigmentation occurring on the face and predominantly affecting women of childbearing age. It is a chronic, often relapsing condition with a negative impact on quality of life. Current treatments for melasma are unsatisfactory.

OBJECTIVE

The aim of this article was to conduct an evidence-based review of interventions available for the treatment of melasma.

METHODS

A systematic literature search was performed using PubMed and the keywords 'melasma' or 'chloasma' in the title. The search was further refined by using a filter for 'controlled clinical trials' and 'randomized controlled trial'. The included studies were used to develop recommendations for treatment.

RESULTS

The electronic search yielded a total of 80 citations. Forty studies were included in this review, which had a total of 2,912 participants. Three different therapeutic modalities were investigated-topical agents, chemical peels, and laser and light therapies. Topical depigmenting agents were found to be the most effective in treating moderate-to-severe melasma, with combination therapies, such as triple-combination therapy (hydroquinone, tretinoin, and fluocinolone acetonide), yielding the best results. Chemical peels as well as laser and light therapies were found to have moderate benefit but more studies are needed to determine their efficacy and long-term safety. Adverse events associated with treatment were mild and short-lasting and included skin irritation, dryness, burning, and erythema. The data could not be statistically pooled because of the heterogeneity of treatments and lack of consistency across study designs.

CONCLUSIONS

Topical combination therapies were found to be more effective than monotherapy. Triple combination therapy was found to be the most effective, but approximately 40 % of patients develop erythema and peeling. Chemical peels and laser and light therapies produced mixed results, with increased risk of irritation and subsequent hyperpigmentation, particularly in darker-skinned individuals. Hence, current treatments available for melasma remain unsatisfactory. Many of the studies lacked long-term follow-up. Limitations of current literature include the heterogeneity of study designs, small sample sizes, and poor follow-up rates. Additional evidence for the effects and role of sunscreens is needed. Categorization or stratification of demographic data should also be included in future studies, such as age, melasma type, and duration of melasma prior to initiation of treatment. Patient's perception of improvement versus investigator's assessment of improvement should also be included in future studies and standardized methods of study design and assessment of outcomes are needed to form definitive conclusions on the efficacy of different treatment modalities.

Voriconazole-induced photosensitivity: photobiological assessment of a case series of 12 patients

BACKGROUND

Voriconazole, a broad-spectrum triazole antifungal agent increasingly used to treat aspergillosis, has been linked with acute photosensitivity and skin carcinogenesis. The action spectrum of the photosensitivity is unknown, while an indirect retinol effect secondary to the antifungal's impact on CYP450 enzymes has been proposed to contribute to the underlying mechanism.

OBJECTIVES

To perform a detailed photobiological assessment of the photosensitivity presenting in a series of 12 patients treated with voriconazole.

METHODS

Minimal erythemal dose thresholds (MED) to narrow wavebands of ultraviolet (UV) A, UVB and visible light were determined. Provocation testing was performed to broadband UVA (310-400 nm) and to solar-simulated radiation (SSR) (290-400 nm). Patients underwent routine photopatch testing and laboratory investigations including serum vitamin A (retinol).

RESULTS

Patients (eight men, four women; median age 54years, range 40-63) experienced moderate-severe cutaneous erythema (n = 12), burning pain (n=5), itching (n=3), scaling (n=5), vesiculation (n=5) and oedema (n=1) following sunlight exposure; increased lentigines (n=4) and actinic cheilitis (n = 4) were also observed. While the majority (n=8) of patients showed normal MED thresholds to monochromator phototesting to UVB, UVA and visible light, a low MED to UVA was observed in four patients. Repeated provocation testing with broadband UVA and SSR provoked an abnormal erythema in eight and 10 patients, respectively. Serum retinol levels were mildly elevated in two patients but normal in the majority.

CONCLUSION

 UVA sensitivity is the predominant finding in acute voriconazole-induced photosensitivity. We found little evidence of elevated circulating retinol as the causal factor. Patients with voriconazole-induced photosensitivity require education in appropriate UVA protective measures in addition to consideration of skin surveillance for malignant sequelae.

β-Cryptoxanthin suppresses UVB-induced melanogenesis in mouse: involvement of the inhibition of prostaglandin E2 and melanocyte-stimulating hormone pathways

Objective

β-cryptoxanthin (β-CPX) is a carotenoid that is widely contained in the fruits of citrus plants. We evaluated the effect of β-CPX on UVB-induced pigmentation and mRNA expression related to melanogenesis in mouse skin. In addition, changes in melanogenic molecules were evaluated in cultured melanocytes stimulated with prostaglandin (PG) E2, melanocyte-stimulating hormone (MSH) and endothelin (ET)-1.

Methods

Mice were irradiated with UVB and were given β-CPX (0.1, 1 and 10 mg/kg) orally for 14 days. Pigmentation was evaluated by skin colour change and microscopic observation. Total RNA was obtained from the skin and the expression of melanogenic mRNA was evaluated by RT-PCR. In cell culture studies, human melanocytes were cultured with β-CPX and melanogenic stimulants (PGE2, MSH and ET-1) for 6–10 days. Melanin contents, dendricity, melanogenic mRNA and phosphorylation of cyclic AMP response element-binding protein (CREB) were evaluated.

Key findings

β-CPX (10 mg/kg) significantly suppressed skin pigmentation and mRNA expression of cyclooxygenase-2, ET-1 receptors, low-affinity neurotrophin receptor, PGE2 receptor (EP1), melanocortin 1 receptor (MC1R), tyrosinase (Tyr), tyrosinase-related protein (Tyrp) 1 and microphthalmia transcription factor. β-CPX (10 µg/ml) suppressed melanogenesis induced by PGE2, MSH and ET-1. In the PGE2-stimulated melanocytes, mRNA expressions of EP-1, Tyr and Tyrp1 and phosphorylation of CREB protein were suppressed. In the ET-1-stimulated cells, only expression of CREB protein was suppressed. In the MSH-induced cells, mRNA expression of MC1R and Tyrp1 and protein expression of CREB were suppressed.

Conclusion

Oral administration of β-CPX was found to suppress UVB-induced melanogenesis. Suppression of melanogenic enzymes, receptors of melanogenic stimulators, expression and phosphorylation of CREB are thought to be involved in the mechanism.