Metabolomics Signature and Potential Application of Serum Polyunsaturated Fatty Acids Metabolism in Patients With Vitiligo

Validation of the DLQI questionnaire in assessing the disease burden and principal aspects related to life quality of vitiligo patients

According to many studies, vitiligo has a negative psychological influence on the patient's life. Multiple factors contribute to the severity of the vitiligo disease burden, among which the most important are self-esteem, stress, and stigma. We aimed to measure the importance of health-related life quality in assessing disease burden in patients with vitiligo. We formulated an HA, which is the principal hypothesis, claiming a single fundamental factor that characterizes the life quality of patients with vitiligo. We also formulated 10 important research questions related to the quality of life that can be generally formulated for patients with dermatological illnesses but particularly suited for vitiligo patients. These research questions capture fundamental aspects of the health-related quality of life of vitiligo patients influenced by symptoms and feelings, daily activities, leisure, job and education, personal relationships, and treatment. These also cover specific aspects related to the quality of life, such as skin-caused sexual difficulties, difficulties in social relationships, and difficulties in performing sports, among others. The Dermatology Life Quality Index (DLQI) questionnaire measures the health-related quality of life of persons suffering from skin diseases. We applied this generic questionnaire to patients with vitiligo. Following a set of inclusion and exclusion criteria, we obtained 114 carefully selected patients who responded to all the questions. This study also validated the DLQI questionnaire on persons who suffer from vitiligo. We investigated whether DLQI has acceptable internal consistency by applying Cronbach's alpha internal consistency indicator (Cα). The obtained Cα = 0.914 indicates excellent internal consistency. We also examined whether all the questions in the questionnaire were mathematically consistent, which we finally proved. It was not necessary to remove any of the questionnaire questions. To prove our HA, a Principal Axis Factoring (PAF) was applied, verifying the assumptions regarding the Average Variance Extracted (AVE) and Convergent Validity (CV). HA proved that applying PAF on DLQI resulted in extracting a single general vitiligo latent factor of life quality, with an initial eigenvalue = 5.671, SS loadings = 5.2, and 52 % of the total cumulative variance explained. Diverse statistical analyses were applied to analyze the 10 formulated research questions. The results of the analysis of the research questions are presented and discussed in the manuscript. One of the conclusions related to the analysis of a research question was that sex had the lowest correlation with the latent life quality factor identified for vitiligo patients.

Genome-wide DNA methylation of lesional and peri-lesional skin in vitiligo: a comparative and integrated analysis of multi-omics in Chinese population

Several studies have emphasized the role of DNA methylation in vitiligo. However, its profile in human skin of individuals with vitiligo remains unknown. Here, we aimed to study the DNA methylation profile of vitiligo using pairwise comparisons of lesions, peri-lesions, and healthy skin. We investigated DNA methylation levels in six lesional skin, six peri-lesional skin, and eight healthy skin samples using an Illumina 850 K methylation chip. We then integrated DNA methylation data with transcriptome data to identify differentially methylated and expressed genes (DMEGs) and analyzed their functional enrichment. Subsequently, we compared the methylation and transcriptome characteristics of all skin samples, and the related genes were further studied using scRNA-seq data. Finally, validation was performed using an external dataset. We observed more DNA hypomethylated sites in patients with vitiligo. Further integrated analysis identified 264 DMEGs that were mainly functionally enriched in cell division, pigmentation, circadian rhythm, fatty acid metabolism, peroxidase activity, synapse regulation, and extracellular matrix. In addition, in the peri-lesional skin, we found that methylation levels of 102 DMEGs differed prior to changes in their transcription levels and identified 16 key pre-DMEGs (ANLN, CDCA3, CENPA, DEPDC1, ECT2, DEPDC1B, HMMR, KIF18A, KIF18B, TTK, KIF23, DCT, EDNRB, MITF, OCA2, and TYRP1). Single-cell RNA analysis showed that these genes were associated with cycling keratinocytes and melanocytes. Further analysis of cellular communication indicated the involvement of the extracellular matrix. The expression of related genes was verified using an external dataset. To the best of our knowledge, this is the first study to report a comprehensive DNA methylation profile of clinical vitiligo and peri-lesional skin. These findings would contribute to future research on the pathogenesis of vitiligo and potential therapeutic strategies.

Influences of vitiligo-associated characteristics on the occurrence of diabetes mellitus: Interactive analysis of a cross-sectional study

The risk of diabetes mellitus (DM) in vitiligo patients is higher than that in non-vitiligo population. Our goal was to explore the influencing factors for DM in vitiligo patients. A matched-pair design of 107 cases with DM and 428 controls without DM was conducted among vitiligo patients in Xijing hospital from January 2010 to October 2021. The baseline characteristics of patients were analysed based on standard descriptive statistics. The vitiligo-associated characteristics were analysed by logistic regression to identify influencing factors of DM. Interaction analysis was performed to explore the additive interactions between vitiligo-associated characteristics and baseline characteristics. After adjustment for the baseline characteristics, the severity of vitiligo [odds ratio (OR) = 2.47, 95% confidence interval (CI): 1.47-4.14] and onset age of vitiligo (OR = 0.98, 95% CI: 0.97-0.99) had a significant correlation with occurrence of DM. The severity of vitiligo had additive interaction with family history of diabetes [relative excess risk due to interaction (RERI) = 132.51 (95% CI: 5.51-1100.20), attributable proportion (AP) = 0.91 (95% CI: 0.17-0.95), synergy index (S) = 11.53 (95% CI: 1.32-100.5)] and with smoking history [RERI = 6.54 (95% CI: 0.67-19.83), AP = 0.64 (95% CI: 0.04-0.80), S = 3.48 (95% CI: 1.17-10.36)]. Earlier onset age of vitiligo and greater BSA involvement might be two independent risk factors for DM in vitiligo patients. Interaction assessment identified the severity of vitiligo as additive interaction factors with diabetes family history and with smoking history for the DM occurrence.

Mechanisms of Arachidonic Acid In Vitro Tumoricidal Impact

To promote the potential of arachidonic acid (ARA) for cancer prevention and management, experiments were implemented to disclose the mechanisms of its tumoricidal action. Hepatocellular, lung, and breast carcinoma and normal hepatocytes cell lines were exposed to 0 or 50 μM ARA for 30 min and then assessed for proliferative capacity, surface membrane-associated sphingomyelin (SM) content, neutral sphingomyelinase (nSMase) activity, beta 2 microglobulin (β2 m) expression, and ceramide (Cer) levels. Reactive oxygen species (ROS) content and caspase 3/7 activity were evaluated. Exposure to ARA for 30 min led to impairment of the tumor cells' proliferative capacity and revealed that the different cell lines display remarkably similar surface membrane SM content but diverse responses to ARA treatment. Arachidonic acid tumoricidal impact was shown to be associated with nSMase activation, exposure of cell surface membrane β2 m to antibody binding, and hydrolysis of SM to Cer, which accumulated on the cell surface and in the cytosol. The ARA and Cer-mediated inhibition of tumor cell viability appeared to be independent of ROS generation or caspase 3/7 activation. The data were compared and contrasted to findings reported in the literature on ARA tumoricidal mechanisms.