Soluble ST2 is a biomarker for cardiovascular mortality related to abnormal glucose metabolism in high-risk subjects.

AIMS: Inflammation plays a role in the development and progression of type 2 diabetes macroangiopathy. Interleukin 33 (IL-33) drives production of Th2-associated cytokines. The soluble form of suppression of tumorigenicity 2 (sST2) acting as a decoy receptor blocks IL-33 and tones down Th2 inflammatory response. We investigated the role of sST2 as a predictor of CV and all-cause mortality in a cohort of patients affected by established atherosclerotic disease. METHODS: 399 patients with atherosclerotic disease from the Tor Vergata Atherosclerosis Registry performed follow-up every year by phone interview. The primary endpoint was cardiovascular death and the secondary endpoint was death for any other disease. RESULTS: sST2 plasma levels were significantly increased from normal glucose-tolerant patients to patients with history of type 2 diabetes (p < 0.00001). Levels of sST2 were significantly correlated with fasting plasma glucose (R = 0.16, p = 0.002), HbA1c (R = 0.17, p = 0.002), and HOMA (R = 0.16, p = 0.004). Dividing patients in tertiles of sST2 levels, those belonging to the highest tertile showed an increased rate of all-cause and cardiovascular mortality, (all-cause mortality p = 0.045 and CVD mortality p = 0.02). A multivariate Cox analysis revealed that sST2 increased the risk in cardiovascular mortality per SD by hazard ratio 1.050 (95% CI 1.006-1.097, p = 0.025) after adjustment for age and hs-CRP while it did not significantly change the risk for all-cause mortality. CONCLUSIONS: High circulating level of sST2 is associated to increased CVD mortality and markers of metabolic dysfunction in subjects with atherosclerotic disease.

FoxO1 regulates asymmetric dimethylarginine via downregulation of dimethylaminohydrolase 1 in human endothelial cells and subjects with atherosclerosis.

BACKGROUND AND AIMS: The O subfamily of forkhead (FoxO) 1 is a pivotal element in the regulation of endothelial activation. Compartmentalization and activity of FoxO1 is regulated by post translational modifications, but the implication in endothelial dysfunction and atherosclerosis remain controversial. Our aim was to identify FoxO1 related metabolic signatures in endothelial cells. METHODS AND RESULTS: Using metabolomics in human umbilical endothelial cells (HUVECs) overexpressing the wild type FoxO1 (FoxO1-WT), the acetylation defective mutant (FoxO1-KR), the unphosphorylated nuclear localized mutant (FoxO1-ADA) and the Green Fluorescent Protein (GFP) control vector, we identify metabolic pathways differentially affected by the different FoxO1 localization and activity. Among metabolites, asymmetric dimethylarginine (ADMA) was increased in FoxO1-ADA compared with FoxO1-WT and FoxO1-KR infected cells (p < 0.01). ADMA was further investigated to identify the molecular mechanisms to explain its link to FoxO1. We found that unrestrained FoxO1 activity leads to increase of ADMA via downregulation of its degrading enzyme, dimethylaminohydrolase (DDAH) 1. In human subjects (n = 89) the FoxO1/DDAH1/ADMA pathway marks unstable atherosclerosis. CONCLUSIONS: Our results point to ADMA as a biomarker to track deregulated FoxO1 activity in vivo.