Lipoprotein-associated phospholipase A2 distribution among lipoproteins differs in type 1 diabetes

Background LpPLA 2 mass and activity have been variably related to cardiovascular disease risk, and the distribution of LpPLA 2 in patients with type 1 diabetes (T1D), wherein cardiovascular disease risk is high despite normal or higher levels of high-density lipoprotein (HDL) cholesterol, is unknown. Objective To determine whether there are differences in the distribution of LpPLA 2 mass and activity across lipoproteins and their association with coronary artery calcium (CAC) in patients with T1D. Methods Men with T1D (n = 19) not on statins, with and without CAC progression, and men without diabetes matched for HDL cholesterol (n = 25) had lipoproteins separated by fast protein liquid chromatography. Results Both LpPLA 2 mass and activity were found within low-density lipoprotein (LDL) and HDL pools with more LpPLA 2 mass being associated with HDL (54% vs 44%; P -value 2 activity being associated with LDL (56% vs 40%; P value = .02). In T1D, more LpPLA 2 activity was associated with large- or less-dense LDL compared to those without diabetes. However, no difference in LpPLA 2 activity or mass between lipoprotein subfractions was observed between all groups, and there was no relationship between LpPLA 2 activity or mass and its distribution and CAC score progression in healthy or T1D men. Conclusion LpPLA 2 is found in both LDL and HDL and is distributed differently in men with T1D without any relationship to CAC score progression.