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Background
Stroke burden is extremely high in Chinese hypertensive population. Novel biomarkers for cardiovascular diseases can be detected by metabolomic profiling of human fluids. We aim to find a panel of distinctive plasma metabolites for predicting incident ischemic stroke in hypertensive patients.Methods
This is a nested case-control study from a prospective cohort design. Baseline plasma samples were collected from 66 newly developed ischemic stroke cases and 66 matched controls. Untargeted metabolomics was performed by ultra-high performance liquid chromatography-tandem mass spectrometry, and data were analyzed by multivariate and univariate statistics.Results
Plasma metabolite profiles clearly differed between hypertensive patients with incident ischemic stroke and without. A total of 12 metabolites were screened and identified as potential biomarkers. The altered metabolic pathways included retinol metabolism, sphingolipid metabolism, glycerophospholipid metabolism, lysine degradation, tyrosine metabolism, and tryptophan metabolism. For prediction of hypertensive ischemic stroke, the panel of specific metabolomics-based biomarkers provided area under the curve of 0.848 (95% confidence interval: 0.783-0.913).Conclusions
Our study identified a metabolic signature of incident ischemic stroke in hypertension. Differences in small-molecule metabolites hold translational value in prediction and provide insights into potential new mechanisms of this condition. 相似文献Methods: Peripheral blood was obtained from patients and healthy controls, and Th17 cells were examined.Results: Th17 cells significantly increased the differentiation of CD11c+ and DC-SIGN+ dendritic cells (DCs) from circulating monocytes in the absence of exogenous stimulation as well as in the presence of LPS stimulation. Th17 cells also increased CD80 and CD86 expression by DCs. Importantly, although Th17 cells from both healthy controls and patients with endplate inflammation could induce CD11c, DC-SIGN, CD80, and CD86 expression, Th17 cells from patients with endplate inflammation showed significantly more potent capacity. Both contact-dependent and IL-17-dependent mechanisms were employed by Th17 cells, since blocking cell-to-cell contact significantly inhibited Th17-mediated differentiation of CD11c+ DCs, and neutralization of IL-17 reduced the expression of CD80 and CD86. Strikingly, DCs following incubation with Th17 cells, but not the DCs derived directly from monocytes without Th17 cells, could significantly promote the expression of IL-17 from naive CD4+ T cells.
Conclusions: These results demonstrated that Th17 cells from patients with endplate inflammation could potently induce the differentiation and activation of DCs that preferentially promoted IL-17 response in a positive feedback loop. 相似文献