Petanin, an acylated anthocyanin from the Solanaceae family, shows potential in tyrosinase inhibitory activity and anti-melanogenic effects; however, its mechanism remains unclear. Therefore, to investigate the underlying mechanism of petanin\'s anti-melanogenic effects, the enzyme activity, protein expression and mRNA transcription of melanogenic and related signaling pathways in zebrafish using network pharmacology, molecular docking and molecular dynamics simulation were combined for analysis. The results showed that petanin could inhibit tyrosinase activity and melanogenesis, change the distribution and arrangement of melanocytes and the structure of melanosomes, reduce the activities of catalase (CAT) and peroxidase (POD) and enhance the activity of glutathione reductase (GR). It also up-regulated JNK phosphorylation, inhibited ERK/RSK phosphorylation and down-regulated CREB/MITF-related protein expression and mRNA transcription. These results were consistent with the predictions provided through network pharmacology and molecular docking. Thus, petanin could inhibit the activity of tyrosinase and the expression of tyrosinase by inhibiting and negatively regulating the tyrosinase-related signaling pathway ERK/CREB/MITF through p-JNK. In conclusion, petanin is a good tyrosinase inhibitor and anti-melanin natural compound with significant market prospects in melanogenesis-related diseases and skin whitening cosmetics.

The slow-developing neurological disorder Alzheimer\'s disease (AD) has no recognized etiology. A bioinformatics investigation verified copper metabolism indicators for AD development. GEO contributed AD-related datasets GSE1297 and GSE5281. Differential expression analysis and WGCNA confirmed biomarker candidate genes. Each immune cell type in AD and control samples was scored using single sample gene set enrichment analysis. Receiver Operating Characteristic (ROC) analysis, short Time-series Expression Miner (STEM) grouping, and expression analysis between control and AD samples discovered copper metabolism indicators that impacted AD progression. We test clinical samples and cellular function to ensure study correctness. Biomarker-targeting miRNAs and lncRNAs were predicted by starBase. Trust website anticipated biomarker-targeting transcription factors. In the end, Cytoscape constructed the TF/miRNA-mRNA and lncRNA-miRNA networks. The DGIdb database predicted biomarker-targeted drugs. We identified 57 differentially expressed copper metabolism-related genes (DE-CMRGs). Next, fourteen copper metabolism indicators impacting AD progression were identified: CCK, ATP6V1E1, SYT1, LDHA, PAM, HPRT1, SCG5, ATP6V1D, GOT1, NFKBIA, SPHK1, MITF, BRCA1, and CD38. A TF/miRNA-mRNA regulation network was then established with two miRNAs (hsa-miR-34a-5p and 34c-5p), six TFs (NFKB1, RELA, MYC, HIF1A, JUN, and SP1), and four biomarkers. The DGIdb database contained 171 drugs targeting ten copper metabolism-relevant biomarkers (BRCA1, MITF, NFKBIA, CD38, CCK2, HPRT1, SPHK1, LDHA, SCG5, and SYT1). Copper metabolism biomarkers CCK, ATP6V1E1, SYT1, LDHA, PAM, HPRT1, SCG5, ATP6V1D, GOT1, NFKBIA, SPHK1, MITF, BRCA1, and CD38 alter AD progression, laying the groundwork for disease pathophysiology and novel AD diagnostic and treatment.

Identifying genetic susceptibility factors for complex disorders remains a challenging task. To analyze collections of small and large pedigrees where genetic heterogeneity is likely, but biological commonalities are plausible, we have developed a weights-based pipeline to prioritize variants and genes. The Weights-based vAriant Ranking in Pedigrees (WARP) pipeline prioritizes variants using 5 weights: disease incidence rate, number of cases in a family, genome fraction shared amongst cases in a family, allele frequency and variant deleteriousness. Weights, except for the population allele frequency weight, are normalized between 0 and 1. Weights are combined multiplicatively to produce family-specific-variant weights that are then averaged across all families in which the variant is observed to generate a multifamily weight. Sorting multifamily weights in descending order creates a ranked list of variants and genes for further investigation. WARP was validated using familial melanoma sequence data from the European Genome-phenome Archive. The pipeline identified variation in known germline melanoma genes POT1, MITF and BAP1 in 4 out of 13 families (31%). Analysis of the other 9 families identified several interesting genes, some of which might have a role in melanoma. WARP provides an approach to identify disease predisposing genes in studies with small and large pedigrees.

BACKGROUND: Waardenburg syndrome (WS) is a rare genetic disorder mainly characterized by hearing loss and pigmentary abnormalities. Currently, seven causative genes have been identified for WS, but clinical genetic testing results show that 38.9% of WS patients remain molecularly unexplained. In this study, we performed multi-data integration analysis through protein-protein interaction and phenotype-similarity to comprehensively decipher the potential causative factors of undiagnosed WS. In addition, we explored the association between genotypes and phenotypes in WS with the manually collected 443 cases from published literature.
RESULTS: We predicted two possible WS pathogenic genes (KIT, CHD7) through multi-data integration analysis, which were further supported by gene expression profiles in single cells and phenotypes in gene knockout mouse. We also predicted twenty, seven, and five potential WS pathogenic variations in gene PAX3, MITF, and SOX10, respectively. Genotype-phenotype association analysis showed that white forelock and telecanthus were dominantly present in patients with PAX3 variants; skin freckles and premature graying of hair were more frequently observed in cases with MITF variants; while aganglionic megacolon and constipation occurred more often in those with SOX10 variants. Patients with variations of PAX3 and MITF were more likely to have synophrys and broad nasal root. Iris pigmentary abnormality was more common in patients with variations of PAX3 and SOX10. Moreover, we found that patients with variants of SOX10 had a higher risk of suffering from auditory system diseases and nervous system diseases, which were closely associated with the high expression abundance of SOX10 in ear tissues and brain tissues.
CONCLUSIONS: Our study provides new insights into the potential causative factors of WS and an alternative way to explore clinically undiagnosed cases, which will promote clinical diagnosis and genetic counseling. However, the two potential disease-causing genes (KIT, CHD7) and 32 potential pathogenic variants (PAX3: 20, MITF: 7, SOX10: 5) predicted by multi-data integration in this study are all computational predictions and need to be further verified through experiments in follow-up research.

BACKGROUND: Melanogenesis, regulated by genetic, hormonal, and environmental factors, occurs in melanocytes in the basal layer of the epidermis. Dysregulation of this process can lead to various skin disorders, such as hyperpigmentation and hypopigmentation. Therefore, the present study investigated the effect of ultrasonic-assisted ethanol extract (SHUE) from Sargassum horneri (S. horneri), brown seaweed against melanogenesis in α-melanocyte-stimulating hormone (MSH)-stimulated B16F10 murine melanocytes.
METHODS: Firstly, yield and proximate compositional analysis of the samples were conducted. The effect of SHUE on cell viability has been evaluated by using 3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. After that, the melanin content and cellular tyrosinase activity in α-MSH-stimulated B16F10 murine melanocytes were examined. Western blot analysis was carried out to investigate the protein expression levels of microphthalmia-associated transcription factor (MITF), tyrosinase, tyrosinase-related protein-1 (TRP1), and tyrosinase-related protein-2 (TRP2). In addition, the effect of extracellular signal-regulated kinase (ERK) on the melanogenesis process was assessed via Western blotting.
RESULTS: As per the analysis, SHUE contained the highest average yield on a dry basis at 28.70 ± 3.21%. The findings showed that SHUE reduced the melanin content and cellular tyrosinase activity in α-MSH-stimulated B16F10 murine melanocytes. Additionally, the expression levels of MITF, TRP1, and TRP2 protein were significantly downregulated by SHUE treatment in α-MSH-stimulated B16F10 murine melanocytes. Moreover, SHUE upregulated the phosphorylation of ERK and AKT in α-MSH-stimulated B16F10 murine melanocytes. In addition, experiments conducted using the ERK inhibitor (PD98059) revealed that the activity of SHUE depends on the ERK signaling cascade.
CONCLUSIONS: These results suggest that SHUE has an anti-melanogenic effect and can be used as a material in the formulation of cosmetics related to whitening and lightening.

Abnormal melanogenesis can lead to hyperpigmentation. Tyrosinase (TYR), a key rate-limiting enzyme in melanin production, is an important therapeutic target for these disorders. We investigated the TYR inhibitory activity of hydrolysates extracted from the muscle tissue of Takifugu flavidus (TFMH). We used computer-aided virtual screening to identify a novel peptide that potently inhibited melanin synthesis, simulated its binding mode to TYR, and evaluated functional efficacy in vitro and in vivo. TFMH inhibited the diphenolase activities of mTYR, reducing TYR substrate binding activity and effectively inhibiting melanin synthesis. TFMH indirectly reduced cAMP response element-binding protein phosphorylation in vitro by downregulating melanocortin 1 receptor expression, thereby inhibiting expression of the microphthalmia-associated transcription factor, further decreasing TYR, tyrosinase related protein 1, and dopachrome tautomerase expression and ultimately impeding melanin synthesis. In zebrafish, TFMH significantly reduced black spot formation. TFMH (200 μg/mL) decreased zebrafish TYR activity by 43% and melanin content by 52%. Molecular dynamics simulations over 100 ns revealed that the FGFRSP (T-6) peptide stably binds mushroom TYR via hydrogen bonds and ionic interactions. T-6 (400 μmol/L) reduced melanin content in B16F10 melanoma cells by 71% and TYR activity by 79%. In zebrafish, T-6 (200 μmol/L) inhibited melanin production by 64%. TFMH and T-6 exhibit good potential for the development of natural skin-whitening cosmetic products.

The Microphthalmia-associated Transcription Factor (MITF) governs numerous cellular and developmental processes. In mice, it promotes specification and differentiation of the retinal pigmented epithelium (RPE), and in humans, some mutations in MITF induce congenital eye malformations. Herein, we explore the function and regulation of Mitf in Drosophila eye development and uncover two roles. We find that knockdown of Mitf results in retinal displacement (RDis), a phenotype associated with abnormal eye formation. Mitf functions in the peripodial epithelium (PE), a retinal support tissue akin to the RPE, to suppress RDis, via the Hippo pathway effector Yorkie (Yki). Yki physically interacts with Mitf and can modify its transcriptional activity in vitro. Severe loss of Mitf, instead, results in the de-repression of retinogenesis in the PE, precluding its development. This activity of Mitf requires the protein phosphatase 2 A holoenzyme STRIPAK-PP2A, but not Yki; Mitf transcriptional activity is potentiated by STRIPAK-PP2A in vitro and in vivo. Knockdown of STRIPAK-PP2A results in cytoplasmic retention of Mitf in vivo and in its decreased stability in vitro, highlighting two potential mechanisms for the control of Mitf function by STRIPAK-PP2A. Thus, Mitf functions in a context-dependent manner as a key determinant of form and fate in the Drosophila eye progenitor epithelium.

Skin hyperpigmentation is mainly caused by excessive synthesis of melanin; however, there is still no safe and effective therapy for its removal. Here, we found that the dermal freezer was able to improve UVB-induced hyperpigmentation of guinea pigs without causing obvious epidermal damage. We also mimic freezing stimulation at the cellular level by rapid freezing and observed that freezing treatments <2.5 min could not decrease cell viability or induce cell apoptosis in B16F10 and Melan-A cells. Critically, melanin content and tyrosinase activity in two cells were greatly reduced after freezing treatments. The dramatic decrease in tyrosinase activity was associated with the downregulation of MITF, TYR, TRP-1 and TRP-2 protein expression in response to freezing treatments for two cells. Furthermore, our results first demonstrated that freezing treatments significantly reduced the levels of p-GSK3β and β-catenin and the nuclear accumulation of β-catenin in B16F10 and Melan-A cells. Together, these data suggest that fast freezing treatments can inhibit melanogenesis-related gene expression in melanocytes by regulating the Wnt/β-catenin signalling pathway. The inhibition of melanin production eventually contributed to the improvement in skin hyperpigmentation induced by UVB. Therefore, fast freezing treatments may be a new alternative of skin whitening in the clinic in the future.

BACKGROUND: Hearing loss (HL) is a common sensory impairment worldwide, with genetic and environmental factors contributing to its occurrence. Next Generation Sequencing (NGS) plays a crucial role in identifying the genetic factors involved in this heterogeneous disorder.
RESULTS: In this study, a total of 9 unrelated Iranian families, each having at least one affected individual who tested negative for mutations in GJB2, underwent screening using whole exome sequencing (WES). The pathogenicity and novelty of the identified variant was checked using various databases. Co-segregation study was also performed to confirm the presence of the candidate variants in parents. Plus, The pathogenicity of the detected variant was assessed through in silico analysis using a number of mutation prediction software tools. Among the 9 investigated families, hearing loss-causing genes were identified in 6 families. the mutations were observed in USH2A, CLRN1, BSND, SLC26A4, and MITF, with two of the identified mutations being novel.
CONCLUSIONS: Discovering additional variants and broadening the range of mutations associated with hearing impairment has the potential to enhance the diagnostic effectiveness of molecular testing in patient screening, and can also lead to improved counseling aimed at reducing the risk of affected offspring for high-risk couples.

BACKGROUND: Tokishakuyakusan (TSS), a traditional Kampo medicine, can effectively alleviate symptoms unique to women, such as menstrual pain and menopausal symptoms, and this effect is believed to be related to its ability to increase the secretion of female hormones. TSS is also believed to be effective against skin pigmentation. However, no studies have examined the effect of TSS on pigmentation.
OBJECTIVE: In this study, we conducted basic research to determine the effects of TSS on pigmentation.
METHODS: Female HRM-2 mice were given free access to a normal diet or a TSS-containing diet for 7 weeks. For 3 weeks starting from the 4th week of treatment, the back of the skin was irradiated with ultraviolet (UV) light, and the melanin level was measured. The expression levels of melanogenesis-related genes and inflammatory markers in the skin were analyzed.
RESULTS: The melanin level in the skin of the mice exposed to UV radiation was approximately three times greater than that in the skin of the mice in the non-UV-irradiated group, confirming pigmentation due to UV irradiation. The protein expression levels of tyrosinase (Tyr), tyrosinase-related protein-1 (Tyrp1), and dopachrome tautomerase (Dct), which are important for melanin production, were significantly greater in the UV irradiation group than in the non-UV irradiation group. In contrast, the amount of skin melanin in the mice treated with TSS was significantly lower than that in the UV-irradiated group, and the expression levels of melanogenesis-related enzymes were also lower. Furthermore, TSS significantly decreased the expression of microphthalmia transcription factor (Mitf), a transcription factor for melanogenesis-related enzymes, and the inflammatory cytokines interleukin-1β and interleukin-6.
CONCLUSIONS: TSS inhibits melanin production in melanocytes by suppressing the increase in the expression of melanogenesis-related enzymes caused by UV irradiation. These findings suggested that this effect of TSS is exerted through the combined regulation of MITF expression and anti-inflammatory responses.