Pigmentary Changes Research Articles

Species Survey of Leaf Hyponasty Responses to Warming Plus Elevated CO2.

Atmospheric carbon dioxide (CO2) concentrations are increasing and may exceed 800 ppm by 2100. This is increasing global mean temperatures and the frequency and severity of heatwaves. Recently, we showed for the first time that the combination of short-term warming and elevated carbon dioxide (eCO2) caused extreme upward bending (i.e., hyponasty) of leaflets and leaf stems (petioles) in tomato (Solanum lycopersicum), which reduced growth. Here, we examined additional species to test the hypotheses that warming + eCO2-induced hyponasty is restricted to compound-leaved species, and/or limited to the Solanaceae. A 2 × 2 factorial experiment with two temperatures, near-optimal and supra-optimal, and two CO2 concentrations, ambient and elevated (400, 800 ppm), was imposed on similarly aged plants for 7-10 days, after which final petiole angles were measured. Within Solanaceae, compound-leaf, but not simple-leaf, species displayed increased hyponasty with the combination of warming + eCO2 relative to warming or eCO2 alone. In non-solanaceous species, hyponasty, leaf-cupping, and changes in leaf pigmentation as a result of warming + eCO2 were variable across species.

Evaluation of the Efficacy of the 755 nm Picosecond Laser in Eliminating Pigmented Skin Lesions after a Single Treatment Based on Photographic Analysis with Polarised Light.

Pigmentary changes can be bothersome and affect one's well-being. Laser therapy has been shown to effectively treat such skin discolouration. We aimed to assess the utility of a 755 nm alexandrite laser in pigmented lesions removal. A total of 109 patients aged 44.17 ± 8.2 years were enrolled and underwent laser treatment of facial skin hyperpigmentation. The efficacy was analysed on the basis of photographic diagnosis using the VISIA Complexion Analysis System. The following measures were assessed: (1) score; (2) feature count; (3) comparison figure. A single laser treatment significantly improved the size and area of the lesion and decreased the number of lesion features. Parallelly, the overall skin condition significantly improved (p < 0.05). We found a statistical tendency of a higher feature count baseline, thus its change in men (p = 0.05 and 0.07, respectively), but failed to find any statistically significant associations (p > 0.05) between tested measures and skin phototypes and hyperpigmentation types. Age was also not correlated with the laser efficacy (p > 0.05). The use of the 755 nm laser is effective in reducing pigmented lesions.

Pityriasis rosea: dermoscopic features in Uganda.

The study aimed to describe the dermoscopic features of pityriasis rosea among patients attending the skin clinic at Mbarara Regional Referral Hospital. A hospital-based cross-sectional descriptive study conducted for a 6-month period in the skin clinic of MRRH in Southwestern Uganda. Data were collected from consecutively recruited patients using structured questionnaires. Patients with a clinical diagnosis of pityriasis rosea were examined using a dermoscope and subsequently sent for KOH and TPHA tests to rule out fungal skin infection and secondary syphilis, respectively, and then received routine care at the skin clinic. There were 54 patients with pityriasis rosea seen. Dermoscopy was done on a total of 162 lesions of which 19 were herald patches, 51 were truncal lesions, 52 on the extremities while 40 were on the face and neck regions. Common dermoscopic features consisted of a violaceous background noted in 145 (89.51%), white scales in 161 (99.38%), diffuse scale distribution in 57 (35.19%), perifollicular scale type in 61 (37.65%), and brown-dotted pigmentary changes in 66 (40.74%). Other unique findings noted in a few lesions were cloudy structures, petechial spots, erosions, and punched out pits. Most prevalent dermoscopic features included: a violaceous background, white scales, diffuse scale distribution, perifollicular scale type, brown-dotted pigmentary changes with no visible blood vessels nor follicular changes. Other unique less frequently seen findings were cloudy structures, petechial spots, erosions, and punched out pits.

Therapeutic management of akissing nevus of the eyelid

Congenital divided melanocytic nevi of the upper and lower eyelid are rare pigmented changes of the eyelids. These processes are also known as "kissing nevi," "panda nevi," and "split ocular nevi," and were first described by Fuchs in 1919. About 120cases have been described in the literature so far. Congenital melanocytic nevi are either present at birth (small nevi are already found in about 1% of neonates) or manifest predominantly during the first decade of life. These rare melanocytic changes of the eyelids should be controlled regularly, as malignant transformation can occur. The actual incidence of malignant transformation is highly variable in the literature, ranging from 2 to 40% depending on the duration of follow-up, with an average of 14% for the whole lifetime. Moreover, nevi of the eyelids may be considered cosmetically disturbing and cause functional problems. Therapeutic removal (dermabrasion, cryotherapy, laser therapy, and surgical excision with ophthalmoplastic reconstruction) is rarely medically indicated due to the low risk of malignant transformation. Removal can be performed in cases of secondary amblyopia in ptosis, compression of the lacrimal point, epiphora, or cosmetic desire. Treatment becomes necessary not only in case of suspicious manifestation or impairment of eyelid function, but it also helps to avoid possible bullying at school among children and is recommended at age4 to6 (before school age).

Analysis of the relationship between color and natural pigments of tobacco leaves during curing

Color is one of the most important indicators for the flue-cured tobacco quality. The color change of tobacco has a great relationship with the natural pigments in the tobacco. The relationship between color characteristics and the content of natural pigments in tobacco leaves during curing was investigated. The middle part of variety K326 tobacco was taken at each key time point during the curing process to determine the changes of color characteristics, moisture, pigment and polyphenol content. The results showed that moisture content of wet basis of tobacco gradually decreased from 72 to 18% during the curing process, the b* value increased and then decreased, and the a* value increased significantly. The lutein and β-carotene content decreased to 63.83 μg/g and 28.3 μg/g, respectively. The total polyphenols content increased to 50.19 mg/g. Meanwhile, the a* value was significantly and positively correlated with polyphenols content and negatively correlated with pigments content. Cluster analysis showed that the samples were divided into three categories: samples with the curing time of 0 h, 24–72 h, and 84–132 h. These results demonstrated that the color change of tobacco during curing process can be divided into three stages from the perspective of chemical composition, which are strongly related to the degradation of pigments and the transformation of polyphenols.

Identification and effective regulation of scarb1 gene involved in pigmentation change in autotetraploid Carassius auratus.

The autotetraploid Carassius auratus (4nRR, 4 n=200, RRRR) is derived from whole-genome duplication of Carassius auratus red var. (RCC, 2 n=100, RR). In the current study, we demonstrated that chromatophores and pigment changes directly caused the coloration and variation of 4nRR skin (red in RCC, brownish-yellow in 4nRR). To further explore the molecular mechanisms underlying coloration formation and variation in 4nRR, we performed transcriptome profiling and molecular functional verification in RCC and 4nRR. Results revealed that scarb1, associated with carotenoid metabolism, underwent significant down-regulation in 4nRR. Efficient editing of this candidate pigment gene provided clear evidence of its significant role in RCC coloration. Subsequently, we identified four divergent scarb1 homeologs in 4nRR: two original scarb1 homeologs from RCC and two duplicated ones. Notably, three of these homeologs possessed two highly conserved alleles, exhibiting biased and allele-specific expression in the skin. Remarkably, after precise editing of both the original and duplicated scarb1 homeologs and/or alleles, 4nRR individuals, whether singly or multiply mutated, displayed a transition from brownish-yellow skin to a cyan-gray phenotype. Concurrently, the proportional areas of the cyan-gray regions displayed a gene-dose correlation. These findings illustrate the subfunctionalization of duplicated scarb1, with all scarb1 genes synergistically and equally contributing to the pigmentation of 4nRR. This is the first report concerning the functional differentiation of duplicated homeologs in an autopolyploid fish, substantially enriching our understanding of coloration formation and change within this group of organisms.

Solar exposure, the melanocyte and melanoma: Survival pathways and molecular mechanisms.

The keratinocyte and the melanocyte, the main cellular constituents of the epidermis, are two very different cell types. Despite their different origins and functionality, they come together in the skin, synergistically, to function as a unit to control the adverse effects of solar exposure. The most significant element in this protective process is the ability of the melanocyte to produce melanin. This pigmented polymer is responsible for constitutive skin colour that plays a part in our identity as human individuals but more importantly, provides a tanning response. A change in pigmentation that provides both an immediate and prolonged protective effect from the damaging components of solar radiation. The melanocortin 1 receptor, a cell surface receptor on the melanocyte, receives paracrine stimulation in the form of hormonal communication from the keratinocyte, initiating a series of intracellular molecular interactions in the melanocyte, eventually involving transcription factors in the nucleus, most notably the microphthalmia-associated transcription factor, resulting in upregulation of enzymatic production of melanin and finally, its transfer back to the keratinocyte. The melanocortin 1 receptor is highly polymorphic and unfortunately this results in the Caucasians’ having constitutionally fairer skin combined with an incomplete tanning response, resulting in a higher susceptibility to skin cancer. The melanocyte is a relatively long-lived cell and over its extended life span can accumulate a series of mutational events. With malignant transition to melanoma this oncogenic baggage, when combined with antiapoptotic machinery that helps melanocyte survival, resulting in relatively rapid progression of the malignant process and contributing to its resistance to therapeutics.

Pigmented purpuric dermatoses: A review

Pigmented purpuric dermatosis (PPD) comprises a group of skin conditions characterized by flat, nonpalpable petechiae and purpura as a result of capillaritis. Although the precise cause of PPD is as yet unknown, increased vascular permeability and capillary fragility are key factors in its pathophysiology. PPD has diverse clinical presentations, but the histopathology of all these variants essentially remains the same. The initial purpuric lesions develop a golden-brown hue owing to hemosiderin absorption and eventually progress to chronic pigmentary changes. These lesions, which often affect the lower limbs, are either asymptomatic or accompanied by moderate pruritus, and can be difficult to diagnose and treat. There are several subtypes of clinical presentations that have been documented over the years. In order to accurately diagnose PPD, a thorough clinical evaluation and, occasionally, a biopsy may be required. It is essential to identify the condition and reassure patients of its benign nature. Treatment is usually necessary due to the chronic nature of the condition, its consequences on physical and mental well-being, and the presence of significant lesions or itching. In this review, we outline the various prevalent PPDs and discuss their etiopathogenesis, clinical features, and diagnostic and treatment modalities.

Comparison the Effect of Conventional and Nanofat Injection Methods on Nasolabial Fold Lipofilling: A Case- Control Study.

Nasolabial folds are a common sign of aging, accompanied by various manifestations such as skin and tissue loosening, wrinkles, lip corner drooping, mandibular angle loss, platysmal bands, and skin pigmentation changes. Limited research has explored Nanofat injection methods. this study was done with the aim of comparing the effect of fat injection by two methods, conventional and Nanofat, in nasolabial folds. The study conducted in 2020-2021 at the skin clinic in Ilam, western Iran was a case-control study. Participants were divided into two groups, and lipofilling procedures were performed using conventional and nanofat methods with autologous fat. Data collection utilized a researcher-made questionnaire and radiographic results. Follow-up visits occurred on the 30th, 90th, and 180th days to assess complications and recovery rates. After 6 months, participant's photographs were taken and compared with pre-intervention photographs using the GIAS criteria. Data analysis was conducted using SPSS22 version software. The average age of the participants was 37.80±8.30 yr. The treatment response in the conventional fat injection group was significantly better than the nanofat group (P<0.05). Both groups were satisfied with the treatment methods, but high satisfaction was reported in the conventional group, but there was no statistically significant difference between the groups. Both methods of improving wrinkles were effective, but the improvement and response to treatment in the conventional method was better than the Nanofat method, and its effect was felt by the participants for an average period of 3 months.

The efficacy of antiaging cream with Oxalis dehradunensis R. ethanolic extract as skin aging care among woman agriculture workers.

Skin damage and aging are potential health problems for woman agriculture workers. This study aimed to test the efficacy of Oxalis dehradunensis ethanol extract formulated in antiaging cream preparations as an aging treatment in women agriculture workers. The method carried out was an experimental study on woman agriculture workers who were willing to volunteer. The experimental scenario conducted related to the physical quality of antiaging cream products and the efficacy of creams on the skin as an antiaging treatment. Physical quality parameters of antiaging cream include organoleptic assessment, cream emulsion, homogeneity, viscosity, pH, distribution, and skin irritation test to evaluate potential side effects. Skin aging efficacy assessments were conducted on 12 subjects divided into four formula concentration groups. The physical skin identification parameters measured are moisture, pore size, pigmentation or spots, and wrinkles using a skin analyzer. The results found that O. dehradunensis leaf extract formulated as an antiaging cream can neutralize free radicals and is an effective countermeasure against premature skin aging. There were significant differences in the skin characteristics of woman agriculture workers who participated as samples. The formula with 5% concentrate and 7% extract of O. dehradunensis has provided a reaction and is more effective in continuous treatment. It provides skin moisture changes of more than 300%, disguises pore size and good pigmentation, and reduces wrinkles of farmers who are constantly exposed to chemicals and free radicals in their agricultural activities. The leaf extracts antiaging cream showed more significant changes in moisture and skin pigmentation. It was concluded that the use of O. dehradunensis leaf extract as the core ingredient of antiaging cream can be an innovation that is beneficial to the health of the farming community, especially among women agriculture workers.

Polyphenols targeting multiple molecular targets and pathways for the treatment of vitiligo.

Vitiligo, a pigmentary autoimmune disorder, is marked by the selective loss of melanocytes in the skin, leading to the appearance of depigmented patches. The principal pathological mechanism is the melanocyte destruction mediated by CD8+ T cells, modulated by oxidative stress and immune dysregulation. Vitiligo affects both physical health and psychological well-being, diminishing the quality of life. Polyphenols, naturally occurring compounds with diverse pharmacological properties, including antioxidant and anti-inflammatory activities, have demonstrated efficacy in managing various dermatological conditions through multiple pathways. This review provides a comprehensive analysis of vitiligo and the therapeutic potential of natural polyphenolic compounds. We examine the roles of various polyphenols in vitiligo management through antioxidant and immunomodulatory effects, melanogenesis promotion, and apoptosis reduction. The review underscores the need for further investigation into the precise molecular mechanisms of these compounds in vitiligo treatment and the exploration of their combination with current therapies to augment therapeutic outcomes.

Dermoscopy of Cutaneous Vascular Lesions: An Observational Study

Abstract Introduction: Cutaneous vascular lesions (VLs) comprise of all skin diseases that originate from or affect blood or lymphatic vessels. VLs are expected to show predominant vascular structures (VS) in dermoscope and adequate interpretation of the shapes and distribution of VS lead the observer to the right diagnosis. Objectives: The aim is to study and evaluate the dermoscopic patterns of different types of VLs using polarized white and orange light. Methodology: Patients presenting with VLs including vascular tumours, vascular malformations, purpura, and other miscellaneous conditions were enrolled in this study conducted in dermatology outpatient department. After relevant history and examination, dermoscopic images were captured and stored for the analysis. Results: A total of 170 patients of 20 VLs were studied including 118 males and 52 females. For evaluating dermoscopic features, we described the findings under two headings, key features, and other nonspecific features. In key features, we included lacunae and vascular patterns, whereas in other features, homogenous area, white collarette, white rail lines, peripheral erythema, increased pigment network, brown area, veil, dot, globule, patch, lines and changes in background color, etc., were included. Interestingly, dermoscopy revealed some new features such as half and half lacunae and pattern 4 in angiokeratoma, arciform structures in angioma serpiginosum, silvery globules in subungual hematoma, and many more. Conclusion: Dermsocope can be used as a handy tool to quickly diagnose innocent VLs based on established dermsocopic features and to easily differentiate them from each other and from the malignant lesions.

Dermoscopic Perspective of Pityriasis Versicolor in a Cross-Sectional Study.

Pityriasis versicolor is a common superficial fungal infection which is usually easily diagnosed with Wood's lamp examination and 10% potassium hydroxide mount. However, these modalities have varying sensitivity and specificity. This study aimed to ascertain the dermoscopic features of pityriasis versicolor lesionally as well as perilesionally using dermoscopy, a non-invasive diagnostic tool. In this cross-sectional study, consecutive patients with pityriasis versicolor underwent dermoscopic examination of lesions and 2 cm around lesions, noting lesional and perilesional features. Semi-objective grading of pigmentation, scaling, and vascularity was done. The association between parameters was determined using heat maps and violin plots with Kolmogorov-Smirnov test. Lesional analysis was performed since lesions at different sides showed disparate features. A total of 353 lesions from 233 patients (males = 150/233; 64.38% and females = 84/234; 36.05%) were studied. On lesional dermoscopy, pigmentary and scaling abnormalities were universal. 258/353 (73.1%) of lesions showed vascular abnormalities. Perilesionally, scaling (223/353; 63.17%) followed by pigmentation (205/353; 58.07%) and vascular changes (111/353; 31.44%) constituted the most common dermoscopic abnormalities and were noted in 294/353 (83.29%) of lesions overall. Increased disease duration corresponded with increased intensity of perilesional pigmentation alterations, perifollicular (P = 0.04), and follicular scales (P = 0.02). Awareness of dermoscopic features could improve the diagnostic accuracy in doubtful cases of pityriasis versicolor. Vascular findings are common and may point to an underlying inflammatory pathogenesis. Perilesional findings constitute early dermoscopic features of pityriasis versicolor and hint at the need for treatment beyond the confines of lesions. Larger follow-up studies and research into immunopathogenesis may be of further benefit.

Genetic memory activation of the skin by polyherbal preparation – A new hope for pigmentary disorders of the skin

ABSTRACT The present article describe the photosensitizing effect of Psoralea corylifolia extract specific to accelerate melanogenesis in skin by eliciting the release of certain pro-inflammatory mediators by fibroblast and keratinocytes; responsible for melanogenesis. The process of acceleration of pigmentogenesis which we refer as ‘activation of genetic memory of the skin’. The findings of the cell culture assay using B16F10, fibroblast and keratinocyte cell line studies have been described in the article. Further, the importance of UV irradiation post Psoralea corylifolia extract treatment in releasing the pro-inflammatory mediators by fibroblast and keratinocyte also has been described. The study findings clearly indicate the inclusion of herbal preparations in the treatment of vitiligo which may offer some treatment value, however further confirmation is required.

Global research trends on melasma: a bibliometric and visualized study from 2014 to 2023.

Melasma, a prevalent pigmentary disorder, is characterized by its complex etiology, propensity for recurrence, and resistance to treatment. However, there is currently no research on melasma through bibliometrics and visualisation. This study analyses the hotspots and trends in the field based on 2,709 publications from the Web of Science Core Collection (WOSCC). We carried out bibliometric analyses using Citespace software for different countries/regions, institutions, authors, and keywords. References were also analysed using VoSviewer. The results indicate that overall, there has been an increase in publications related to melasma since 2014. According to the analysis of the collaborative network diagram, the United States, Egyptian Knowledge Bank, and Benjakul Soottawat are the most contributing countries, institutions, and authors, respectively. Reference and keyword analyses have identified the pathogenesis and treatment of melasma as a prevalent topic in recent years. And how to find new treatment options and more effective therapeutic drugs is a future research trend. This is the first bibliometric and visual analysis of melasma-related literature to explore research hotspots and trends.

Targeting phosphorylation circuits on CREB and CRTCs as the strategy to prevent acquired skin hyperpigmentation.

Background: The cAMP response element-binding protein (CREB) and CREB-regulated transcription coactivators (CRTCs) cooperate in the transcriptional activation of microphthalmia-associated transcription factor subtype M (MITF-M) that is a master regulator in the biogenesis, pigmentation and transfer of melanosomes at epidermal melanocytes. Here, we propose the targeting of phosphorylation circuits on CREB and CRTCs in the expression of MITF-M as the rationale to prevent skin hyperpigmentation by elucidating the inhibitory activity and mechanism of yakuchinone A (Yaku A) on facultative melanogenesis. Methods: We employed human epidermal melanocyte cell, mouse skin, and mouse melanoma cell, and applied Western blotting, reverse transcription-polymerase chain reaction, immunoprecipitation and confocal microscopy to conduct this study. Results: This study suggested that α-melanocyte stimulating hormone (α-MSH)-induced melanogenic programs could switch on the axis of protein kinase A-salt inducible kinases (PKA-SIKs) rather than that of PKA-AMP activated protein kinase (PKA-AMPK) during the dephosphorylation of CRTCs in the expression of MITF-M. SIK inhibitors rather than AMPK inhibitors stimulated melanin production in melanocyte cultures in the absence of extracellular melanogenic stimuli, wherein SIK inhibitors increased the dephosphorylation of CRTCs but bypassed the phosphorylation of CREB for the expression of MITF-M. Treatment with Yaku A prevented ultraviolet B (UV-B)-irradiated skin hyperpigmentation in mice and inhibited melanin production in α-MSH- or SIK inhibitor-activated melanocyte cultures. Mechanistically, Yaku A suppressed the expression of MITF-M via dually targeting the i) cAMP-dependent dissociation of PKA holoenzyme at the upstream from PKA-catalyzed phosphorylation of CREB coupled with PKA-SIKs axis-mediated dephosphorylation of CRTCs in α-MSH-induced melanogenic programs, and ii) nuclear import of CRTCs after SIK inhibitor-induced dephosphorylation of CRTCs. Conclusions: Taken together, the targeting phosphorylation circuits on CREB and CRTCs in the expression of MITF-M could be a suitable strategy to prevent pigmentary disorders in the skin.

Plasma Metabolomics Indicates Potential Biomarkers and Abnormal Metabolic Pathways in Female Melasma Patients.

Melasma is a common and chronic pigmentary disorder with complex pathogenesis, and the relationship between melasma and metabolic syndrome remains elusive. Thus, metabolomics might contribute to the early detection of potential metabolic abnormalities in individuals with melasma. The present study aims to analyze changes in plasma metabolites of female melasma patients and identify disease markers as well as explore potential therapeutic targets. Plasma samples from 20 female patients with melasma and 21 healthy female controls that were comparable in terms of age and body mass index were collected for untargeted metabolomics investigations. Ultra-high performance liquid chromatography-mass spectrometry was used to analyze metabolites in the plasma. Metabolic pathway analyses were employed to identify significantly differentially expressed metabolites in melasma patients. Receiver operating characteristic curves were constructed, and correlation analyses were performed using the modified Melasma Area and Severity Index and oxidative stress levels. In contrast to healthy subjects, melasma patients showed significant alterations in 125 plasma metabolites, including amino acids, lipids, and carbohydrate-related metabolites. KEGG pathway analysis suggested that primary pathways associated with the development of melasma include tryptophan metabolism, as well as the biosynthesis of phenylalanine, tyrosine, and tryptophan. Importantly, based on receiver operating characteristic curves and correlation analyses, several metabolites were identified as robust biomarkers for melasma. Collectively, this study identified significant changes in plasma metabolites in melasma patients, providing new insights into the pathogenesis of melasma and opening novel therapeutic avenues.

Interruption of p38MAPK-MSK1-CREB-MITF-M pathway to prevent hyperpigmentation in the skin.

Background: Melanocortin 1 receptor (MC1R), a receptor of α-melanocyte-stimulating hormone (α-MSH), is exclusively present in melanocytes where α-MSH/MC1R stimulate melanin pigmentation through microphthalmia-associated transcription factor M (MITF-M). Toll-like receptor 4 (TLR4), a receptor of endotoxin lipopolysaccharide (LPS), is distributed in immune and other cell types including melanocytes where LPS/TLR4 activate transcriptional activity of nuclear factor (NF)-κB to express cytokines in innate immunity. LPS/TLR4 also up-regulate MITF-M-target melanogenic genes in melanocytes. Here, we propose a molecular target of antimelanogenic activity through elucidating inhibitory mechanism on α-MSH-induced melanogenic programs by benzimidazole-2-butanol (BI2B), an inhibitor of LPS/TLR4-activated transcriptional activity of NF-κB. Methods: Ultraviolet B (UV-B)-irradiated skins of HRM-2 hairless mice and α-MSH-activated melanocyte cultures were employed to examine melanogenic programs. Results: Topical treatment with BI2B ameliorated UV-B-irradiated skin hyperpigmentation in mice. BI2B suppressed the protein or mRNA levels of melanogenic markers, such as tyrosinase (TYR), MITF-M and proopiomelanocortin (POMC), in UV-B-exposed and pigmented skin tissues. Moreover, BI2B inhibited melanin pigmentation in UV-B-irradiated co-cultures of keratinocyte and melanocyte cells and that in α-MSH-activated melanocyte cultures. Mechanistically, BI2B inhibited the activation of cAMP response element-binding protein (CREB) in α-MSH-induced melanogenic programs and suppressed the expression of MITF-M at the promoter level. As a molecular target, BI2B primarily inhibited mitogen-activated protein kinase (MAPK) kinase 3 (MKK3)-catalyzed kinase activity on p38MAPK. Subsequently, BI2B interrupted downstream pathway of p38MAPK-mitogen and stress-activated protein kinase-1 (MSK1)-CREB-MITF-M, and suppressed MITF-M-target melanogenic genes, encoding enzymes TYR, TYR-related protein-1 (TRP-1) and dopachrome tautomerase (DCT) in melanin biosynthesis, and encoding proteins PMEL17 and Rab27A in the transfer of pigmented melanosomes to the overlaying keratinocytes in the skin. Conclusion: Targeting the MKK3-p38MAPK-MSK1-CREB-MITF-M pathway was suggested as a rationale to inhibit UV-B- or α-MSH-induced facultative melanogenesis and as a strategy to prevent acquired pigmentary disorders in the skin.

Clinical spectrum of pigmentary disorders in an Indian skin at an urban tertiary teaching hospital

Clinical spectrum of pigmentary disorders in an Indian skin at an urban tertiary teaching hospital

The Effect of Fractional Carbon Dioxide Laser on Melanogenesis in Human Melanocytes and Vitiligo Mouse Models.

Vitiligo is an acquired skin pigmentation disorder, the cause of which is poorly understood. Researchers in this field are dedicated to exploring novel treatments for achieving re-pigmentation. Mice were randomly selected and divided into control, model, and model+laser groups. Evaluate the impact of different levels of carbon dioxide laser irradiation on tyrosinase activity, melanocyte viability, and melanin content. In this study, it was found that the cell viability and melanin content were significantly enhanced in human melanocytes after treatment with different energy densities of fractional carbon dioxide laser. In addition, laser-treated vitiligo mouse models showed mild pathological changes. Therefore, we believe that fractional carbon dioxide laser may be a potential adjunctive modality for treating vitiligo.