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Background/Aims: Whether maternal vitamin D deficiency is associated with gestational diabetes remains controversial. This meta-analysis aimed to systematically evaluate published evidence on the association between maternal vitamin D status and the risk of gestational diabetes. Methods: We retrieved relevant articles from the PubMed, Medline and Embase databases up to May 2017 for observational studies investigating the association between vitamin D status and the risk of gestational diabetes. Odds ratios (OR) or risk ratios (RR) from individual studies were pooled using the fixed and random effect models. Results: The meta-analysis of 29 observational studies included 28,982 participants, of which 4,634 were diagnosed with gestational diabetes, and showed that maternal vitamin D insufficiency was associated with a significantly increased risk of gestational diabetes by 39% (pooled OR = 1.39, 95%CI = 1.20-1.60) with moderate heterogeneity (I2 = 50.2%; P = 0.001). Moreover, the 25(OH)D level was significantly lower in gestational diabetes cases than in controls with a pooled effect of -4.79 nmol/L (95% CI = -6.43, -3.15). Significant heterogeneity was also detected (I2 = 65.0%, P < 0.001). Further subgroup analysis indicated that this association was also evident in most subpopulations. Conclusion: This meta-analysis indicated a significant association between vitamin D insufficiency and increased risk of gestational diabetes. Further well-designed large-scale clinical trials are essential to verify this association. [ABSTRACT FROM AUTHOR]

Background/Aims: Vitamin D deficiency has been shown to be associated with a greater prevalence of anemia in various healthy and diseased populations by a great deal of observational studies. However, less work has been done to explore this association in pregnant women. The aim of this study was to evaluate the association between maternal serum 25-hydroxyvitamin D [25(OH)D] concentrations and risk of gestational anemia in a large, nested case-control study. Methods: The serum 25(OH)D concentrations was measured by enzyme immunoassay in 775 pregnant women affected with anemia and 1550 controls. Logistic regression analysis was conducted to assess the association of 25(OH)D concentrations with risk of gestational anemia. Results: We found the 25(OH)D concentrations was significantly lower in women affected with anemia than in controls. Logistic regression analyses showed that women with 25(OH)D concentrations < 25.0 nmol/L, from 25.0 to 37.4 nmol/L and from 37.5 to 49.9 nmol/L all had increased risk of anemia when compared with women with concentrations from 50.0 to 74.9 nmol/L. And the risk of anemia was significantly increased with the decreasing concentrations of the serum 25(OH)D in a dose-dependent manner (P for trend = 0.012). For women with concentrations < 50.0 nmol/L, they had an 80% increase in anemia risk (95% CI = 1.45-2.25) after adjustment for confounders. We also observed a nonlinear relationship between the serum 25(OH)D and anemia, with a threshold for 25(OH)D of 50.0 nmol/L existed for anemia. Conclusion: Maternal serum 25(OH)D < 50.0 nmol/L may be a risk factor for gestational anemia, and it should be monitored for the high-risk pregnant women. [ABSTRACT FROM AUTHOR]

Background/Aims: Pro-angiogenic factors VEGF and IL-8 play a major role in modulating the migratory potential of endothelial cells. The goal of this study was to investigate the effect of autocrine VEGF and IL-8 in the form of self-conditioned medium (CM) on human umbilical vein endothelial cells (HUVECs). Methods: Enzyme-linked immunosorbent assay (ELISA) examined the automatic secretion of VEGF and IL-8 protein by HUVECs. Western blot, small interfering RNA (siRNA), pulldown and Transwell assays were used to explore the role and the mechanism of autocrine VEGF and IL-8 in migration of HUVECs. Results: Neutralizing VEGF and IL-8 in CM significantly abrogated CM-induced migration of HUVECs. Autocrine VEGF and IL-8 increased Src phosphorylation, Rac1 activity and PAK1 phosphorylation in a time dependent manner. Additionally, blocking Rac1 activity with Rac1 siRNA largely abolished autocrine VEGF and IL-8-induced cell migration. Vav2 siRNA suppressed autocrine VEGF and IL-8-induced Rac1 activation and cell migration. Furthermore, blocking Src signaling with PP2, a specific inhibitor for Src, markedly prevented autocrine VEGF and IL-8-induced Vav2 and Rac1 activation as well as consequently cell migration. PAK1 siRNA also significantly abolished autocrine VEGF and IL-8-induced cell migration. Conclusions: We demonstrated for the first time that autocrine VEGF and IL-8 promoted endothelial cell migration via the Src/Vav2/Rac1/PAK1 signaling pathway. This finding reveals the molecular mechanism in the increase of endothelial cell migration induced by autocrine growth factors and cytokines, which is expected to provide a novel therapeutic target in vascular diseases. [ABSTRACT FROM AUTHOR]

Background/Aims: MicroRNA-29b (miR29b) has been previously identified in early mouse embryos through miRNA microarray analysis. Recent research has indicated that miR29b participates in DNA methylation by regulating DNA methyltransferase 3a/3b (Dnmt3a/3b) expression. However, the expression pattern and biological function of miR29b in mouse preimplantation embryonic development remain unknown. Methods: In this study, we examined the expression patterns of miR29b and Dnmt3a/3b in mouse early embryos at different developmental stages. Subsequently, expression and localization of DNMT3A/3B protein was analyzed in mouse early embryos by immunofluorescence staining. The biological function of miR29b in mouse early embryos was analyzed by microinjection of commercially available miRNA-specific inhibitors and mimics. Results: Our data showed that Dnmt3a/3b mRNA expression is negatively regulated by miR29b in mouse early embryos. Immunofluorescence analysis revealed that DNMT3A/3B protein expression is predominantly localized within the nucleoplasm of embryos. Alterations to the activity of miR29b could change the DNA methylation levels in mouse preimplantation embryos and lead to a developmental blockade, from the morula to the blastocyst stage. Conclusion: These results indicated a role for the miR29b-Dnmt3a/3b-DNA methylation axis in mouse early embryonic development, and we provide evidence that miR29b is indispensable for mouse early embryonic development. This study contributes to a preliminary understanding of the role of miR29b during mouse embryonic development. © 2015 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background/Aims: Obesity and the related metabolic syndrome have emerged as major public health issues in modern society. miRNAs have been shown to play key roles in regulating obesity-related metabolic syndrome, and some miRNAs regulated by adiponectin were identified as novel targets for controlling adipose tissue inflammation. miR-378 is a candidate target that was shown to be involved in adipose differentiation, mitochondrial metabolism and systemic energy homeostasis. However, little is known about the regulatory mechanisms of miR-378 expression. To better understand the physiological role of miR-378 in obesity and metabolic syndrome, it is crucial that we understand the regulation of miR-378 gene expression in human adipocytes. Methods: In this study, we investigated the effects of adipokines and inflammatory cytokines on miR-378 expression using Real-time PCR and the potential regulatory mechanisms using luciferase reporter assays and electrophoretic mobility shift assay (EMSA). Results: We found that adipokines and cytokines upregulated miR-378 expression primarily through SREBP and C/EBP binding sites in the miR-378 promoter region. Conclusion: Our findings showed that adipokines induced miR-378 expression and revealed the most likely mechanism of adipokine-induced miR-378 dysregulation in human adipocytes. miRNAs have been shown to function in regulating obesity-related metabolic syndrome, and miR-378 may be a novel target for controlling adipose tissue inflammation. This study offers a theoretical basis for understanding systemic adipose tissue inflammation and may provide new strategies for clinical treatment. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Polycystic ovary syndrome (PCOS), the most common endocrinopathy in women of reproductive age, is characterized by polycystic ovaries, chronic anovulation, hyperandrogenism and insulin resistance. Despite the high prevalence of hyperandrogenemia, a definitive endocrine marker for PCOS has so far not been identified. Circulating miRNAs have recently been shown to serve as diagnostic/prognostic biomarkers in patients with cancers. Our current study focused on the altered expression of serum miRNAs and their correlation with PCOS. Method and Results: We systematically used the TaqMan Low Density Array followed by individual quantitative reverse transcription polymerase chain reaction assays to identify and validate the expression of serum miRNAs of PCOS patients. The expression levels of three miRNAs (miR-222, miR-146a and miR-30c) were significantly increased in PCOS patients with respect to the controls in our discovery evaluation and followed validation. The area under the receiver operating characteristic (ROC) curve (AUC) is 0.799, 0.706, and 0.688, respectively. The combination of the three miRNAs using multiple logistic regression analysis showed a larger AUC (0.852) that was more efficient for the diagnosis of PCOS. In addition, logistic binary regression analyses show miR-222 is positively associated with serum insulin, while miR-146a is negatively associated with serum testosterone. Furthermore, bioinformatics analysis indicated that the predicted targets function of the three miRNAs mainly involved in the metastasis, cell cycle, apoptosis and endocrine. Conclusion: Serum miRNAs are differentially expressed between PCOS patients and controls. We identified and validated a class of three serum miRNAs that could act as novel non-invasive biomarkers for diagnosis of PCOS. These miRNAs may be involved in the pathogenesis of PCOS. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]