Search Results (170)

Solar lentigines, commonly caused by prolonged ultraviolet exposure, raise the risk of skin disorders and remain challenging to manage due to their complex mechanisms. Understanding the molecular mechanisms driving the progression of solar lentigines is crucial for developing effective protective strategies. In this study, we introduced a novel method, Dynamic Network Driver (DND), which identifies upstream regulators that drive disease progression by integrating the Dynamic Network Biomarker (DNB) approach with network control theory. By applying DND to multi-omics data from solar lentigines subjects, we (1) identified the key drivers associated with solar lentigo progression, with their functions involved in differentiation and dermal–epidermal junction; and (2) highlighted ARNT2 and TBX2 as significant master factors supported by in vitro validation in melanocytes and pigmented 3D living skin equivalent models. These results demonstrate the potency of DND for uncovering the molecular mechanisms behind solar lentigines and informing therapeutic strategies. In summary, the DND approach identified novel drivers of solar lentigo progression, acting as new markers for spot mitigation in 3D spot mimic models. Full article

Skin pigmentation results from complex cellular interactions and is influenced by genetic, environmental, and metabolic factors. Emerging evidence highlights the multiple pathways by which lipids regulate melanogenesis and points to lipid metabolism and signaling as key players in this process. Lipidomics is a high-throughput omics approach that enables detailed characterization of lipid profiles, thus representing a valid tool for evaluating skin lipid functional role in both physiological melanogenesis and pigmentary disorders. The use of lipidomics to gain a deeper comprehension of the role of lipids in skin pigmentation is still an evolving field, but it has allowed the identification of significant lipid dysregulation in several pigmentary pathologies. This review summarizes the current knowledge on the involvement of lipids in skin pigmentation, focusing on lipid profile alterations described in hyper- and hypopigmentary disorders such as post-inflammatory hyperpigmentation, melasma, solar lentigo, and vitiligo. Lipidomic profiling reveals disease-specific alterations supporting the pivotal role of lipid signaling in the physiopathological mechanisms of melanogenesis. These findings provide insights into disease pathogenesis and show promise for the discovery of biomarkers and innovative therapeutic strategies for pigmentary disorders. Full article

Background: Melasma is an acquired hyperpigmentation disorder with multifactorial etiologies and limited response to conventional therapies. Recent evidence suggests that Botulinum Toxin A (BoNT-A) may modulate ultraviolet (UV)-induced pigmentation and offer therapeutic benefits. Objective: We sought to evaluate the efficacy and safety of two intradermal dilutions of Letibotulinum toxin A (LetiBoNT-A) in Thai patients with melasma. Methods: In this randomized, double-blind, split-face study, 30 participants aged 32–62 years received a single intradermal injection of LetiBoNT-A, with 20 units administered per cheek. A 1:5 dilution was injected on one side of the face, and a 1:10 dilution was injected on the contralateral side. Outcomes were evaluated over a 6-month period using the Hemi-modified Melasma Area and Severity Index (Hemi-mMASI), VISIA^® brown spot analysis, and quantitative assessments of skin texture. Results: Both dilutions significantly improved Hemi-mMASI scores (1:5, p = 0.043; 1:10, p = 0.002) and brown spots (1:5, p = 0.002; 1:10, p < 0.001). The 1:10 dilution showed earlier and more sustained improvements. Subgroup analysis revealed greater reductions in Hemi-mMASI scores among patients with telangiectatic melasma, particularly with the 1:10 dilution, though they were not statistically significant. Additionally, the 1:10 dilution significantly reduced pore volume, pore area, and sebum levels. One case of transient facial asymmetry was reported with the 1:5 dilution. Conclusions: LetiBoNT-A is a safe and effective adjunct in melasma treatment. The 1:10 dilution offered superior clinical outcomes. Full article

Skin aging is a multifactorial process driven by both intrinsic mechanisms—such as telomere shortening, oxidative stress, hormonal decline, and impaired autophagy—and extrinsic influences including ultraviolet radiation, pollution, smoking, and diet. Together, these factors lead to the structural and functional deterioration of the skin, manifesting as wrinkles, pigmentation disorders, thinning, and reduced elasticity. This review provides an integrative overview of the biological, molecular, and clinical dimensions of skin aging, emphasizing the interplay between inflammation, extracellular matrix degradation, and senescence-associated signaling pathways. We examine histopathological hallmarks and molecular markers and discuss the influence of genetic and ethnic variations on aging phenotypes. Current therapeutic strategies are explored, ranging from topical agents (e.g., retinoids, antioxidants, niacinamide) to procedural interventions such as lasers, intense pulsed light, photodynamic therapy, microneedling, and injectable biostimulators. Special attention is given to emerging approaches such as microneedle delivery systems, with mention of exosome-based therapies. The review underscores the importance of personalized anti-aging regimens based on biological age, phototype, and lifestyle factors. As the field advances, integrating mechanistic insights with individualized treatment selection will be key to optimizing skin rejuvenation and preserving long-term dermal health. Full article

Vitiligo, an autoimmune disorder causing depigmented skin patches, includes two types, segmental (SV) and non-segmental (NSV). Previously, NSV was off-label treated using Calcineurine inhibitors (Tacrolimus and Pimecrolimus). In 2022, the FDA approved Ruxolitinib cream, targeting the JAK/STAT pathway for NSV treatment based on promising results. This research conducts a retrospective descriptive safety assessment of Tacrolimus, Pimecrolimus, and Ruxolitinib safety in vitiligo treatment, utilizing the FDA Adverse Event Reporting System (FAERS) database spanning the period from 2013 to 2023 and including patients aged 2 years and above, encompassing both brand and generic names. A total of 844 adverse event reports involving 388 patients were extracted and categorized into dermatological and systemic groups for analysis. Tacrolimus resulted in 12 hospitalizations, two life-threatening events, and four disabilities. Pimecrolimus exhibited urticaria and pigmentation disorders, with tooth fracture as the primary systemic event. Pericarditis was the predominant systemic side effect of Ruxolitinib, followed by anemia, headache, and urosepsis. Local dermatological side effects reported were generally mild, not warranting treatment cessation. In conclusion, vitiligo significantly impacts patients’ psychological well-being, necessitating continuous post-marketing safety monitoring for topical medications. Full article

Cutaneous manifestations can serve as early and sometimes the first clinical indicators in various hereditary cancer predisposition syndromes. This review provides a comprehensive overview of the dermatological signs associated with these syndromes, aiming to facilitate their recognition in clinical practice. Hereditary Breast and Ovarian Cancer syndrome is notably linked to an increased risk of melanoma. BAP1 tumor predisposition syndrome is characterized by BAP1-inactivated melanocytic tumors. Muir–Torre syndrome, a variant of Lynch syndrome, presents with distinctive cutaneous neoplasms such as sebaceous carcinomas, sebaceous adenomas, and keratoacanthomas. PTEN hamartoma tumor syndrome commonly features hamartomatous growths, trichilemmomas, acral keratoses, oral papillomas, and genital lentiginosis. Gorlin syndrome is marked by basal cell carcinomas and palmoplantar pits, while Peutz–Jeghers syndrome is identified by mucocutaneous pigmentation. In familial adenomatous polyposis, the cutaneous findings include epidermoid cysts, fibromas, desmoid tumors, and lipomas. Additionally, we examined monogenic disorders associated with cancer risk and skin involvement, such as xeroderma pigmentosum, neurofibromatosis type 1, familial atypical multiple-mole melanoma syndrome, and Fanconi anemia. The early recognition of these dermatologic features is essential for a timely diagnosis and the implementation of appropriate surveillance strategies in individuals with hereditary cancer syndromes. Full article

Systemic sclerosis (SSc) is an autoimmune fibrotic disorder affecting the skin and internal organs, categorized as either limited cutaneous SSc, where distal areas of skin are involved, or diffuse cutaneous SSc, where more extensive proximal skin involvement is seen. Vascular remodelling and internal organ involvement are frequent complications in both subsets. Multiple pathogenic mechanisms have been demonstrated, including production of disease-specific autoantibodies, endothelial cell damage at an early stage, infiltration of involved tissues by immune cells, as well as environmental factors triggering the onset such as solvents and viruses. Although not strongly familial, susceptibility to SSc is associated with multiple single nucleotide polymorphisms in immunoregulatory genes relevant to antigen presentation, T cell signalling and adaptive immunity, as well as innate immunity. In addition, several lines of evidence demonstrate abnormalities within the epithelial cell layer in SSc. Macroscopically, the SSc epidermis is pigmented, thickened and stiff and strongly promotes myofibroblasts in co-culture. Moreover, multiple activating factors and pathways have been implicated in the disease epidermis, including wound healing responses, induction of damage associated molecular patterns (DAMPS) and the release of pro-fibrotic growth factors and cytokines. Similar to SSc, data from studies of cutaneous wound healing indicate a major role for epidermal keratinocytes in regulating local fibroblast responses during repair of the wound defect. Since the epithelium is strongly exposed to environmental factors and richly populated with protective immune cells, it is possible that disease-initiating mechanisms in SSc involve dysregulated immunity and tissue repair within this cell layer. Treatments designed to restore epithelial homeostasis or else disrupt epithelial–fibroblast cross-talk could be of benefit in this severe and resistant disease. Accordingly, single cell analysis has confirmed an active signature in SSc keratinocytes, which was partially reversed following a period of JAK inhibitor therapy. Full article

Background/Objectives: Cowden syndrome (or PTEN hamartoma tumor syndrome) (CS/PHTS) belongs to a group of inherited disorders associated with the development of multiple hamartomas. The clinical presentation of patients may include dysmorphic facial features, macrocephaly, developmental delay, and multiple benign and malignant tumors of various localizations. At the same time, only thyroid cancer is thought to have an increased risk in childhood. Skin lesions in CS/PHTS occur in 90–100% of patients and include multiple tricholemmoma, papilloma, acral keratosis, pigmentation changes, as well as rarer forms like vascular malformations, fibromas, neuromas, melanoma, and basal cell carcinoma. Methods: Next-generation sequencing and Sanger sequencing were used to search for PTEN genetic variants. A histological and immunohistochemical examination of tumor biopsies and skin lesions was performed. Results: A total of 13 patients from six families with CS/PHTS, including 10 children, were described. Seven pediatric patients belonged to families with paternal transmission of the PTEN pathogenic variants, while three others were de novo cases. Atypical manifestations in CS/PHTS were diffuse large B-cell lymphoma in one adult, a renal cell carcinoma, three germ cell tumors, and a linear epidermal nevus in pediatric patients. A literature review of the identified pathogenic variants in the PTEN gene was performed, assessing their clinical significance and analyzing the traditional and modified diagnostic criteria as applied to the pediatric population. Conclusions: Taking into account the low incidence of CS/PHTS, the data presented significantly expand our current understanding of this disease and guide physicians to consider a wider range of possible malignant neoplasms in pediatric patients with CS/PHTS. Full article

Lasers are widely employed in the treatment of melanocytic lesions. This scoping review evaluates 77 studies on the efficacy and safety of laser treatments for café-au-lait macules (CALMs), nevus of Ota (NOA), Becker’s nevus (BN), lichen planus pigmentosus (LPP), and other pigmented lesions. The Q-switched neodymium-doped yttrium aluminum garnet (Nd:YAG), particularly the 1064 nm, is the most frequently utilized laser, demonstrating strong efficacy for NOA and other dermal pigmentary disorders. Medium-wavelength lasers, including the Q-switched ruby and Alexandrite lasers, also show promise, though results vary based on lesion depth, skin type, and treatment protocols. Recurrence and adverse effects, including post-inflammatory hyperpigmentation (PIH) and hypopigmentation, are common, particularly in patients with darker skin tones. Future studies should standardize and optimize laser parameters across lesion types and skin tones, improve long-term efficacy, and prioritize inclusion of patients with diverse Fitzpatrick skin types to evaluate differential outcomes and promote equitable treatment efficacy. Full article

Excessive melanogenesis causes abnormal pigmentation and a higher risk of skin disorders (e.g., melanoma). Resveratrol (RSV), a natural polyphenol, exerts antioxidant and anti-aging effects. However, the effects of RSV and its derivatives on melanogenesis remain unclear. This study investigated their effects on melanogenesis and antioxidant activity in B16F10 cells. After measuring cell viability, B16F10 cells were incubated with 50 µM of RSV, dihydroresveratrol (DIRSV), and other RSV derivatives for 24 h. The relative melanin content and tyrosinase activity were quantified. The protein and mRNA levels of melanogenesis-related genes (MITF, CREB, TYR, and TRP) and the binding affinity of RSV derivatives to their target proteins were measured. The antioxidant activity was evaluated using ABTS and DPPH assays. RSV and DIRSV (50 µM) significantly reduced melanin content and tyrosinase activity, respectively. However, other derivatives had no significant effects. RSV, DIRSV, and other derivatives significantly suppressed MITF and CREB levels. Additionally, DIRSV significantly reduced p-CREB and TYR protein levels and showed a higher affinity for CREB than RSV, despite no significant changes in MITF, TYR, or TRP mRNA levels. In the antioxidant assays, RSV and DIRSV exhibited significant ABTS and DPPH radical scavenging activities. DIRSV, like RSV, inhibits melanogenesis and exhibits antioxidant effects in B16F10 cells. However, RSV derivatives demonstrate partial antioxidant activity and inhibit melanogenesis-related proteins but do not significantly affect melanogenesis. DIRSV’s practical applications as a skin-protective and -whitening agent warrant further exploration. Full article

Skin photoaging, driven primarily by ultraviolet radiation, remains a critical dermatological concern. Carotenoids, a class of natural pigments with potent antioxidant properties, have emerged as promising agents for preventing and mitigating photoaging. This review comprehensively integrates current understanding regarding the triggers of skin photoaging, oxidative stress and their associated signal pathways, the photoprotective roles and mechanisms of carotenoids, as well as their bioavailability. Common C₄₀ carotenoids, such as β-carotene, lycopene, astaxanthin, lutein, and zeaxanthin demonstrate remarkable antioxidant activity, primarily attributed to their conjugated double bond structures. Many studies have demonstrated that both oral and topical administration of these C₄₀ carotenoids can effectively alleviate skin photoaging. Specifically, they play a crucial role in promoting the formation of a new skin barrier and enhancing the production of collagen and elastin, key structural proteins essential for maintaining skin integrity and elasticity. Mechanistically, these carotenoids combat photoaging by effectively scavenging reactive oxygen species and modulating oxidative stress responsive signal pathways, including MAPK, Nrf2, and NF-κB. Notably, we also anticipate the anti-photoaging potential of novel carotenoids, with a particular emphasis on bacterioruberin, a C₅₀ carotenoid derived from halophilic archaea. Bacterioruberin exhibits a superior radical scavenging capacity, outperforming the conventional C₄₀ carotenoids. Furthermore, when considering the application of carotenoids, aspects such as safe dosage, bioavailability, and possible long term usage issues, including allergies and pigmentation disorders, must be taken into account. This review underscores the anti-photoaging mechanism of carotenoids, providing strategies and theoretical basis for the prevention and treatment of photoaging. Full article

Neoplastic disorders, particularly malignant carcinomas, are complex systemic diseases characterized by unregulated cellular proliferation, the invasion of adjacent tissues, and potential metastasis to distant bodily sites. Among the diverse spectrum of cancer subtypes, malignant melanoma is a highly aggressive form of cutaneous cancer originating in melanocytes, the pigment-producing cells resident in the skin. This malignancy is distinguished by its rapid and uncontrolled growth, as well as its propensity for metastasis to vital organs, thereby posing significant challenges to therapeutic intervention and prognostication. Early detection of melanoma is crucial for optimizing patient outcomes, as diagnosis at an advanced stage often yields a poor prognosis and limited treatment options. Diagnostic modalities for melanoma encompass comprehensive clinical evaluations by dermatologists; radiological imaging techniques such as ultrasonography, magnetic resonance imaging (MRI), computed tomography (CT) scans; and excisional biopsies for accurate histopathological assessment. Malignant melanoma is typically treated with surgery to remove the tumor, followed by immunotherapy to enhance the immune response, targeted therapy for tumors with specific genetic mutations, chemotherapy for advanced stages, radiation therapy to manage metastasis, and other adjunct therapies. This review presents the properties and possible adjunct therapeutic effects against malignant melanoma of quercetin found in the literature and explores, based on the observed physicochemical properties and biological activity, its potential development as a topical formulation for cutaneous application. Quercetin is a naturally occurring flavonoid compound abundant in various plant-based food sources, including apples, onions, berries, and citrus fruits, and has exhibited promising antiproliferative, antioxidant, and anticancer properties. Its distinctive biochemical structure enables quercetin to effectively neutralize reactive oxygen species and modulate key carcinogenic pathways, thereby rendering it a potential candidate for therapeutic intervention in managing malignant tumors, including melanoma. Full article

Background/Objectives: This study aims to investigate the effects of 5,7-dihydroxy-4-methylcoumarin (5,7D-4MC) on melanogenesis in B16F10 murine melanoma cells and to evaluate its safety as a potential ingredient for functional cosmetics and therapeutic agents targeting pigmentation-related disorders. Method: The cytotoxicity of 5,7D-4MC was assessed using an MTT assay, and melanin content and tyrosinase activity were measured at different concentrations (25, 50, 100 µM). Western blot analyses were conducted to evaluate the expression of key melanogenesis-related proteins (TYR, TRP-1, TRP-2, and MITF) and to investigate the regulation of major signaling pathways, including PKA/cAMP, GSK3β, and PI3K/AKT. Additionally, a human primary skin irritation test was performed on 32 participants to assess the dermatological safety of 5,7D-4MC. Results: 5,7D-4MC did not affect cell viability at concentrations below 100 µM and significantly promoted melanin production in a dose-dependent manner. Tyrosinase activity and the expression levels of melanogenic proteins increased significantly following 5,7D-4MC treatment. PKA and GSK3β pathways were activated, while the PI3K/AKT pathway was downregulated. The skin irritation test showed that 5,7D-4MC exhibited low irritation potential at concentrations of 50 µM and 100 µM. Conclusions: 5,7D-4MC enhances melanogenesis and demonstrates low skin irritation, making it a promising candidate for therapeutic applications in treating hypopigmentation disorders, such as vitiligo, as well as a functional cosmetic ingredient. However, further studies involving human melanocytes and clinical trials are required to validate their efficacy. Full article

Background/Objectives: Oleuropein (OLP), the key bioactive in olive leaf extracts, has demonstrated various biological benefits. We previously reported on the pro-melanogenic action with increased dendricity of a patented olive leaf extract (Benolea^®) that was standardized to 16–24% OLP. In this study, purified OLP was evaluated to identify if it might be the bioactive responsible for the stimulating effects on melanocytes. Moreover, previous studies on OLP have never reported the effects on melanocyte dendricity or melanin export in the medium. Methods: Herein, the effect of OLP on melanogenesis was first evaluated using the B16F10 cell model and validated using the physiological model of normal human melanocytes from Caucasian (lightly pigmented; LP) and Asian (moderately pigmented; MP) skin. The effects of OLP on melanin export in LP and MP cells were indirectly evaluated by dendricity indices. Results: OLP lowered the intracellular melanin content in B16F10 cells by 26.36%, 24.48%, and 27.71% at 100, 150, and 200 µg/mL (all p < 0.01), respectively, with no effect on the intracellular melanin contents of LP or MP cells. OLP treatment did not influence tyrosinase activity in B16F10 cells or MP cells but significantly enhanced the activity in LP cells. The measurement of extracellular melanin showed significantly higher levels for all three cells, although the levels were considerably higher in MP cells, after the adjustment for OLP autoxidation observed in the cell-free system, which caused melanin-like brown coloration. Furthermore, OLP induced morphological alterations of extended dendrites of B16F10 cells that were retained in LP and MP cells. The quantitation of the dendricity of cells treated with OLP at 200 μg/mL revealed that the total dendrite length was increased by 35.24% (p < 0.05) in LP cells and by 58.45% (p < 0.001) in MP cells without any change in the dendrite number. Conclusions: This is the first study to demonstrate the novel finding that OLP possesses a hitherto unreported unique capacity to stimulate melanocyte dendricity, hence establishing the efficacy for use in increasing human pigmentation. Our findings show significance, with a potential application of the compound OLP for addressing human hypopigmentation disorders in clinical settings or for cosmetic uses related to sunless tanning. Full article

Skin cancer is a class of disorder defined by the growth of abnormal cells on the body. Accurately identifying and diagnosing skin lesions is quite difficult because skin malignancies share many common characteristics and a wide range of morphologies. To face this challenge, deep learning algorithms have been proposed. Deep learning algorithms have shown diagnostic efficacy comparable to dermatologists in the discipline of images-based skin lesion diagnosis in recent research articles. This work proposes a novel deep learning algorithm to detect skin cancer. The proposed CAD-Skin system detects and classifies skin lesions using deep convolutional neural networks and autoencoders to improve the classification efficiency of skin cancer. The CAD-Skin system was designed and developed by the use of the modern preprocessing approach, which is a combination of multi-scale retinex, gamma correction, unsharp masking, and contrast-limited adaptive histogram equalization. In this work, we have implemented a data augmentation strategy to deal with unbalanced datasets. This step improves the model’s resilience to different pigmented skin conditions and avoids overfitting. Additionally, a Quantum Support Vector Machine (QSVM) algorithm is integrated for final-stage classification. Our proposed CAD-Skin enhances category recognition for different skin disease severities, including actinic keratosis, malignant melanoma, and other skin cancers. The proposed system was tested using the PAD-UFES-20-Modified, ISIC-2018, and ISIC-2019 datasets. The system reached accuracy rates of 98%, 99%, and 99%, consecutively, which is higher than state-of-the-art work in the literature. The minimum accuracy achieved for certain skin disorder diseases reached 97.43%. Our research study demonstrates that the proposed CAD-Skin provides precise diagnosis and timely detection of skin abnormalities, diversifying options for doctors and enhancing patient satisfaction during medical practice. Full article