Lipidomic signature of abdominal aortic aneurysm and peripheral artery disease

Vascular diseases are powerful and significant predictors of cardiovascular mortality, but they are typically under-recognized and undertreated. There is no effective medical therapy for either abdominal aortic aneurysms (AAA) or peripheral artery disease (PAD). Furthermore, it remains unclear which patients will experience cardiovascular events or disease progression. Lipids are key molecules in cardiovascular diseases and good candidates for diagnosis, monitoring and risk prediction, nonetheless there is very limited information on the lipidomic profile of patients with AAA and PAD. We hypothesise that lipids can be used as important prognostic biomarkers of these diseases. To achieve this, we conducted a comprehensive lipidomic analysis of plasma from 11 AAA and 5 PAD patients undergoing open repair surgery, comparing their profiles with healthy controls (n=5). Plasma lipidomic analysis through C18 RP-LC-MS/MS revealed that AAA and PAD patients show alterations in the phospholipid and sphingolipid profile. We observed a marked reduction in PAD and AAA of the relative abundances of (i) phospholipids bearing polyunsaturated fatty acids (PUFAs), primarily from the phosphatidylcholine (PC), phosphatidylethanolamine (PE), and phosphatidylinositol (PI) classes, mostly due to oxidative degradation and (ii) plasmalogen species of PC and PE, which serve as endogenous antioxidants. On the other side, SM and Cer increased in both AAA and PAD. Our findings suggest a dysregulation of the lipid metabolism in AAA and PAD compared with healthy controls that deserves to be explored to unravel putative biomarkers or disease hallmarks.