MicroRNA­21­5p protects melanocytes via targeting STAT3 and modulating Treg/Teff balance to alleviate vitiligo.

Vitiligo (VIT) is caused by loss and degradation of functional epidermal melanocytes. Studies have indicated that melanocyte destruction may be associated with an imbalance between regulatory T cells (Treg cells) and effector T cells (Teff cells). The current study aimed to investigate the molecular mechanism through which Treg/Teff balance affects VIT pathogenesis. To explore this, peripheral blood mononuclear cells were isolated from patients with VIT and healthy individuals. The present study revealed that the proportions of CD4+ T cells, Treg cells and T helper 1 (Th1) cells were decreased in patients with VIT, but those of Teff cells (Th17 and Th22 cells) were increased; additionally, Foxp3 expression was decreased, but the expression levels of interferon­Î³, interleukin (IL)­17A and IL­22 were increased. Furthermore, in patients with VIT, microRNA (miR)­21­5p expression was decreased, while that of STAT3 was increased. Further in vitro experiments in CD4+ T cells revealed that STAT3 was targeted by miR­21­5p. Functional analysis further indicated that miR­21­5p overexpression in Th17­polarized CD4+ T cells decreased the proportion of Teff cells and associated cytokines, such as IL­17A and IL­22, but increased the proportion of Treg cells and Foxp3. However, the effects of miR­21­5p overexpression were partly reversed by STAT3 overexpression. Increased apoptosis of melanocytes was detected after co­culture with Th17­polarized CD4+ T cells in the presence of a miR­21­5p mimic. However, this indirect effect of the miR­21­5p mimic on melanocytes was decreased via STAT3 overexpression. Therefore, miR­21­5p may protect melanocytes via targeting STAT3 and regulating Treg/Teff balance. The current findings may provide a possible treatment method for managing VIT.

Serum level of antioxidant vitamins and minerals in patients with vitiligo, a systematic review and meta-analysis.

BACKGROUND: Antioxidant status is considered as important factor in the pathogenesis of vitiligo. However, there are controversial findings about serum status of antioxidants in vitiligo patients. The purpose of this study was to systematically review the evidences comparing the serum levels of antioxidant vitamins and minerals between vitiligo patients and controls, and performing meta-analysis of the results. METHODS: A comprehensive search was performed for studies comparing the serum status of antioxidant vitamins and minerals using following databases since inception up to 30 April 2020; PubMed, EMBASE, Scopus, and Web of Science. Data extraction was done by two independent reviewers. The data was pooled for serum level of each antioxidant comparing between vitiligo and control groups. RESULTS: Thirteen studies were included in this systematic review. The serum level of vitamin A, C, E, selenium, zinc and copper were compared between vitiligo patients and controls in these studies. Eleven studies including 570 vitiligo cases and 580 controls were included in the meta-analysis. Serum vitamin A and copper level in vitiligo patients were only evaluated in single studies and not included in meta-analysis. Based on fixed effect model, there were no statistical difference between two groups regarding serum vitamin C (OR = 1.17, 95 % CI, 0.74-1.84, P = 0.495), and vitamin E (OR = 0.61, 95 % CI, 0.30-1.25, P = 0.180). Higher serum zinc can decrease the risk of vitiligo based on sensitivity analysis of the results. (OR = 0.29, 95 % CI 0.15-0.54, P < 0.001). Higher serum selenium level significantly increased the risk of vitiligo (OR = 4.31, 95 % CI, 2.72-6.81, P < 0.001). Vitamin A was not significantly different in two reported groups (6.35 ±â€¯1.53 vs 6.77 ±â€¯1.46 µg/mL, P > 0.05). Copper was significantly higher in vitiligo patients compared to controls (129 ±â€¯33 vs 99 ±â€¯19 µg /100 mL, P = 0.002). CONCLUSION: The current meta-analysis of data on serum level of most studied antioxidants (vitamin C, vitamin E, zinc and selenium) in patients suffering vitiligo showed that higher serum selenium (OR = 4.31) and lower zinc level (OR = 0.29) can increased the risk of vitiligo. Potential mechanism associated with preventive effects of zinc and the depigmentation effect of selenium should be more elucidated in further studies.

Health risk assessment of rare earth elements in cereals from mining area in Shandong, China.

To investigate the concentrations of rare earth elements in cereals and assess human health risk through cereal consumption, a total of 327 cereal samples were collected from rare earth mining area and control area in Shandong, China. The contents of 14 rare earth elements were determined by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). The medians of total rare earth elements in cereals from mining and control areas were 74.22 µg/kg and 47.83 µg/kg, respectively, and the difference was statistically significant (P < 0.05). The wheat had the highest rare earth elements concentrations (109.39 µg/kg and 77.96 µg/kg for mining and control areas, respectively) and maize had the lowest rare earth elements concentrations (42.88 µg/kg and 30.25 µg/kg for mining and control areas, respectively). The rare earth elements distribution patterns for both areas were characterized by enrichment of light rare earth elements. The health risk assessment demonstrated that the estimated daily intakes of rare earth elements through cereal consumption were considerably lower than the acceptable daily intake (70 µg/kg bw). The damage to adults can be neglected, but more attention should be paid to the effects of continuous exposure to rare earth elements on children.

Single nucleotide polymorphism in the SEPS1 gene may contribute to the risk of various human diseases: a meta-analysis.

BACKGROUND: Recently the G-105A promoter polymorphism in SEPS1 has been shown to increase pro-inflammatory cytokine expression and, thus, to be correlated with various types of human cancers and diseases. AIMS: This study examined whether this functional polymorphism was related to the risks of several human diseases by performing a meta-analysis. SUBJECTS AND METHODS: This study identified all published studies in MEDLINE, Science Citation Index, the Cochrane Library, PubMed, Embase, Current Contents Index and three Chinese databases. RESULTS AND CONCLUSIONS: Eleven case-control studies were incorporated into this meta-analysis. The results showed that carriers of the rs28665122 G > A polymorphism in the SEPS1 gene are at increased risk of developing diseases under five genetic models. According to the ethnicity-stratified sub-group analysis, SEPS1 rs28665122 polymorphism is significantly linked to increased risk of developing related diseases in Europeans under five genetic models; but not among Asians. This data indicates a statistical association between SEPS1 rs28665122 G > A variants and the development of various human diseases. Such findings suggest that SEPS1 may be a potential gene marker for disease diagnosis and prognosis.