Abstract 103: Circulating sRAGE is Elevated in Patients with Marfan Syndrome and Decreases After Surgical Replacement of Diseased Aortic Segments

Abstract

Backgound: The Receptor for Advanced Glycation End products (RAGE) and its ligands are associated with vascular remodeling and trigger the release of a soluble receptor (sRAGE). We previously demonstrated that sRAGE levels are elevated in patients with bicuspid aortic valve and ascending aortic aneurysm. Circulating sRAGE in these patients correlates with the presence of a dysfunctional aortic structure but do not linearly correlate with an increase in the aortic diameter. Severe aortic disease occurs in more than 80% of Marfan Syndrome (MFS) patients. Aortic root and ascending aorta (AA) enlargement in MFS are associated with deficiency/destabilization of fibrillin-1, which leads to a generalized structural impairment of the aortic wall. We hypothesized that sRAGE may be elevated in the plasma of MFS patients and may decrease after surgical replacement of diseased aortic tissue. Methods: Plasma samples and clinical information (MFS=120, Control=37) were obtained from the GenTAC bioregistry and the Tissue Biobank at UPENN. Samples were collected either a few days prior to aortic surgery or at least one year post-surgery. sRAGE was tested using ELISA. Univariate and multivariate analysis were performed. Results: sRAGE levels are significantly higher in MFS patients compared to control (1404±64.35 vs 592±34.86 pg/ml, p<0.001) and are associated with the presence of MFS, independent of age, gender and comorbidities (p<0.001). sRAGE levels are significantly higher in MFS patients undergoing aortic surgery when compared to MFS patients monitored for aortic disease (1485±116.8 vs 1209±82.63 pg/ml, p=0.05). Circulating sRAGE is significantly lower in patients who have received aortic surgery (1185±63.31 pg/ml, p=0.02) and even lower in patients who received more extensive replacement (aortic valve/root and AA) versus those who underwent only aortic valve and root replacement (1313±81.83 vs 963.5±92.54 pg/ml, p=0.008). sRAGE levels do not linearly correlate with root and/or AA diameter. Conclusion: Plasma sRAGE levels are associated with the presence of ascending aortopathies independent of aortic diameter. Longitudinal studies evaluating sRAGE in MFS patients may unveil new markers for the diagnosis and risk stratification of this population.