BACKGROUND: Although observational studies have suggested a correlation between vitiligo and rheumatic diseases, conclusive evidence supporting a causal relationship is still lacking. Therefore, this study aims to explore the potential causal relationship between vitiligo and rheumatic diseases.
METHODS: Using genome-wide association studies, we performed a two-sample Mendelian randomization (MR) analysis. In our analysis, the random-effects inverse variance weighted (IVW) method was predominantly employed, followed by several sensitivity analyses, which include heterogeneity, horizontal pleiotropy, outliers, and \"leave-one-out\" analyses.
RESULTS: The genetically predicted vitiligo was associated with an increased risk of rheumatoid arthritis (RA) (OR, 1.47; 95% confidence interval [CI], 1.29-1.68; p < 0.001), and systemic lupus erythematosus (SLE) (OR, 1.22; 95% CI, 1.06-1.39; p = 0.005). The causal associations were supported by sensitivity analyses. In Sjögren\'s syndrome and ankylosing spondylitis, no causal relationship with vitiligo was found in the study.
CONCLUSIONS: Our MR results support the causal effect that vitiligo leads to a higher risk of RA and SLE. Individuals with vitiligo should be vigilant for the potential development of RA and SLE. Managing and addressing this potential requires regular monitoring.

OBJECTIVE: Vitiligo is a chronic dermatological condition characterized by the progressive loss of melanocytes, for which traditional therapy has shown limited efficacy. This study aimed to establish a vitiligo model with easy operability, high repeatability, and stable depigmentation to provide a foundation for studying the pathogenesis and developing novel therapies for vitiligo.
METHODS: (1) Establishing vitiligo model: Firstly, deliver B16F10 cells to the back skin of C57BL/6 J via intradermal injection (day 0), and the CD4 depletion antibody was injected intraperitoneally on day 4 and 10. Secondly, the melanoma was surgically removed on day 12. Thirdly, CD8 antibody was administered intraperitoneally every fourth day till day 30. (2) Identification of vitiligo model: H&E staining, immunohistochemistry, and immunofluorescence were used to detect the melanocytes. The melanin was detected by transmission electron microscopy (TEM), Lillie ferrous sulfate staining and L-DOPA staining.
RESULTS: (1) The back skin and hair began to appear white on day 30. Melanin loss reached peak on day 60; (2) Hematoxylin and eosin (H&E) staining, immunohistochemistry and immunofluorescence results showed melanocytes were reduced. L-DOPA staining, Lillie ferrous sulfate staining and TEM results showed that melanin decreased in the epidermis.
CONCLUSIONS: We successfully establishment a vitiligo mouse model which can be more capable to simulate the pathogenesis of human vitiligo and provide an important basis for the study of pathogenesis and therapy of vitiligo.

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BACKGROUND: Tryptophan metabolism dysregulation has been observed in vitiligo. However, drawing a mechanistic linkage between this metabolic disturbance and vitiligo pathogenesis remains challenging.
OBJECTIVE: Aim to reveal the characterization of tryptophan metabolism in vitiligo and investigate the role of tryptophan metabolites in vitiligo pathophysiology.
METHODS: LC-MS/MS, dual-luciferase reporter assay, ELISA, qRT-PCR, small interfering RNA, western blotting, and immunohistochemistry were employed.
RESULTS: Kynurenine pathway activation and KYAT enzyme-associated deviation to kynurenic acid (KYNA) in the plasma of stable non-segmental vitiligo were determined. Using a public microarray dataset, we next validated the activation of kynurenine pathway was related with inflammatory-related genes expression in skin of vitiligo patients. Furthermore, we found that KYNA induced CXCL10 upregulation in keratinocytes via AhR activation. Moreover, the total activity of AhR agonist was increased while the AhR concentration per se was decreased in the plasma of vitiligo patients. Finally, higher KYAT, CXCL10, CYP1A1 and lower AhR expression in vitiligo lesional skin were observed by immunohistochemistry staining.
CONCLUSIONS: This study depicts the metabolic and genetic characterizations of tryptophan metabolism in vitiligo and proposes that KYNA, a tryptophan-derived AhR ligand, can enhance CXCL10 expression in keratinocytes.

BACKGROUND: The prevalence of social media as a source of medical information has grown substantially in recent years, especially for skin conditions disproportionately affecting individuals with skin of color, such as melasma, keloids, and vitiligo.
OBJECTIVE: This study aims to evaluate the nature of content related to these conditions on social media platforms, Instagram and TikTok.
METHODS: In March 2023, the top five hashtags for melasma, keloid, and vitiligo were identified on both platforms. For each hashtag, the 10 most popular posts were selected, based on Instagram and TikTok algorithms. A content analysis was conducted, categorizing posts as Educational, Promotional, or Inspirational. Posts were further classified by content creator type.
RESULTS: For the top 50 posts related to melasma on Instagram, the majority were promotional (58%), with the most common source being non-dermatologist social media influencers (50%). Dermatologists were the primary content creators for specific hashtags, such as #Melasma on TikTok, where the content was predominantly educational.
CONCLUSIONS: Considering the high prevalence of dermatologist-creator content on TikTok, it is crucial to continue this shift toward dermatologist-driven educational content, as social media platforms continue to grow. These platforms are valuable channels for dermatologists to educate a broader audience, facilitating the dissemination of accurate medical information.J Drugs Dermatol. 2024;23(7):510-514. doi:10.36849/JDD.7716.

BACKGROUND: While the prevalence of vitiligo is similar across racial and ethnic groups, the effects of vitiligo vary by demographic group, culture, and skin color, with darker-skinned individuals facing greater stigma due to increased visibility of the disease.1,2 The recruitment of diverse participants that are representative of the United States (US) population is crucial to ensuring the generalizability of findings and understanding the impacts of vitiligo across diverse patient groups.   Objectives: This study aimed to determine demographic reporting trends in US vitiligo clinical trials and to determine whether participants are representative of the US population.
METHODS: A search for US vitiligo clinical trials was conducted on clinicaltrials.gov. Trials conducted between 2006 to September 5, 2023, were included if they intended to treat vitiligo, were conducted in the US, and were completed or terminated.  Results: Of the 15 trials meeting inclusion criteria, only 60% (n=9) reported participant race/ethnicity. These 9 studies included 1,510 participants, of which only 25.43% (n=384) were non-White and 20.40% were Hispanic. There was disproportionately low representation of racial minorities, particularly Black, Native American, and Native Hawaiian groups.   Limitations: Limitations of our study include small sample size, variations in demographic reporting between trials, and undercounting of minority groups by the US Census.  Conclusions: Racial and ethnic minority groups remain underrepresented in US vitiligo clinical trials. Given that the impact of vitiligo can vary by the affected individual’s demographic group and skin color, investigators must be intentional about including a more diverse and representative population in vitiligo clinical trials.  J Drugs Dermatol. 2024;23(7):e164-e166. doi:10.36849/JDD.8117e.

A comprehensive analysis of spatial transcriptomics was carried out to better understand the progress of halo nevus. We found that halo nevus was characterized by overactive immune responses, triggered by chemokines and dendritic cells (DCs), T cells, and macrophages. Consequently, we observed abnormal cell death, such as apoptosis and disulfidptosis in halo nevus, some were closely related to immunity. Interestingly, we identified aberrant metabolites such as uridine diphosphate glucose (UDP-G) within the halo nevus. UDP-G, accompanied by the infiltration of DCs and T cells, exhibited correlations with certain forms of cell death. Subsequent experiments confirmed that UDP-G was increased in vitiligo serum and could activate DCs. We also confirmed that oxidative response is an inducer of UDP-G. In summary, the immune response in halo nevus, including DC activation, was accompanied by abnormal cell death and metabolites. Especially, melanocyte-derived UDP-G may play a crucial role in DC activation.

Vitiligo has been reported to occur in association with lupus erythematosus (LE) and other autoimmune diseases. However, it remains unclear whether this association occurs because of shared immunopathogenesis. We hereby describe a case of discoid lupus erythematosus (DLE) in a 51-year-old man with a 3 years history of skin lesions on his face, arms, and the V zone of the neck, and with the coexistence of vitiligo for 12 years, who developed from DLE to hypertrophic discoid lupus erythematosus (HDLE) after 10 months. We reviewed the previously reported cases to summarize the clinical characteristics of these patients and hope it may provide a reference for dermatologists.

Fibroblasts are crucial components of the skin structure. They were traditionally believed to maintain the skin\'s structure by producing extracellular matrix and other elements. Recent research illuminated that fibroblasts can respond to external stimuli and exhibit diverse functions, such as the secretion of pro-inflammatory factors, adipogenesis, and antigen presentation, exhibiting remarkable heterogeneity and plasticity. This revelation positions fibroblasts as active contributors to the pathogenesis of skin diseases, challenging the traditional perspective that views fibroblasts solely as structural entities. Based on their diverse functions, fibroblasts can be categorized into six subtypes: pro-inflammatory fibroblasts, myofibroblasts, adipogenic fibroblasts, angiogenic fibroblasts, mesenchymal fibroblasts, and antigen-presenting fibroblasts. Cytokines, metabolism, and epigenetics regulate functional abnormalities in fibroblasts. The dynamic changes fibroblasts exhibit in different diseases and disease states warrant a comprehensive discussion. We focus on dermal fibroblasts\' aberrant manifestations and pivotal roles in inflammatory and autoimmune skin diseases, including psoriasis, vitiligo, lupus erythematosus, scleroderma, and atopic dermatitis, and propose targeting aberrantly activated fibroblasts as a potential therapeutic strategy for inflammatory and autoimmune skin diseases.

UNASSIGNED: Vitiligo is an autoimmune disease characterized by loss of skin pigmentation and currently has no effective treatment. This study aimed to investigate the function of SIRT7, being an important desuccinylase mediating multiple disease progression, and its mechanism in vitiligo progression.
UNASSIGNED: Normal human melanocytes (NHM) PIG1 and vitiligo human melanocytes (VHM) PIG3V were utilized in this research. The role of sirtuin 7 (SIRT7) and Ezrin (EZR) on melanin synthesis was investigated by detecting tyrosinase activity, melanin content, α-MSH levels, and the protein levels of melanin-related markers. The function of EZR was identified via rescue experiments, while the underlying mechanism was investigated via bioinformatic analysis, co-immunoprecipitation (co-IP), immunoprecipitation (IP), and Western blot techniques.
UNASSIGNED: Results showed that only SIRT7 was highly expressed in vitiligo human melanocytes, where knockingdown SIRT7 translated into increased melanin synthesis in melanocytes. Mechanistically, SIRT7 knockdown promoted the succinylation of EZR at the Lys (K)60 site. Moreover, overexpressing EZR induced higher melanin synthesis in melanocytes, while its knocking down exerted the opposite effect by inhibiting SIRT7 knockdown-induced melanin synthesis.
UNASSIGNED: SIRT7 inhibited melanin synthesis in melanocytes by suppressing the succinylation of EZR. These findings are envisaged to provide a novel theoretical basis for vitiligo treatment.