Abstract Body (Do not enter title and authors here): Introduction: Chronic kidney disease (CKD) is a common inflammatory disease affecting >15% of the adult population and 50% of all patients with advanced/end stages (4 to 5) of CKD have cardiovascular disease. Research Questions: How multiple disease risk factors interplay to accelerate vascular inflammation in CKD. Aim: To determine whether hyperlipidemia and CKD have a synergy in accelerating vascular inflammation via trained immunity (TI). Methods: we performed aortic pathological analysis and RNA-sequencing in high-fat diet (HFD)-fed 5/6 nephrectomy CKD (HFD+CKD) mice. Results: 1) HFD+CKD increases aortic cytosolic lipopolysaccharide (LPS) levels, caspase-11 (casp11) activation, and 998 gene expressions of TI pathways in the aorta (first-tier TI mechanism); 2) Casp11^—/— decreases aortic neointima hyperplasia, aortic recruitment of macrophages, and casp11-gasdermin D-mediated cytokine secretion; 3) Casp11^—/— decreases N-terminal gasdermin D (N-GSDMD) membrane expression on aortic endothelial cells and aortic IL-1b levels; 4) LPS transfection into human aortic endothelial cells results in casp4 (human)/casp11 (mouse) activation and increases N-GSDMD membrane expression; 5) IL-1b serves as the second-tier mechanism underlying HFD+CKD-promoted TI. Conclusion: Hyperlipidemia and CKD accelerate vascular inflammation by promoting two-tier trained immunity