Aortic wall lymphocytes in diabetes and atherosclerosis

University Of Virginia, Charlottesville VA

Investigators

Linked publications & trials

Abstract

Patients with diabetes suffer from increased incidence and severity of atherosclerotic cardiovascular[unreadable] diseases. To study the mechanisms through which diabetes accelerates vascular disease, we have identified[unreadable] mouse models of insulin resistance, i.e. C57BL/6 apoE-/- mice fed a fat-rich western diet and insu|in receptor[unreadable] and insulin receptor substrate-1 double heterozygous (IR+/-IRS1+/-) mice, which we have successfully[unreadable] crossed into the apolipoprotein E-deficient (apoE-/-) mouse on the C57BL/6 background. ApoE-/- mice, like[unreadable] humans at elevated risk for atherosclerotic cardiovascular disease, show monocyte-derived macrophages[unreadable] and foam cells and T-helper 1 cells (Th1) in lesions. The role B cells and other lymphocytes in diabetesaccelerated[unreadable] atherosclerosis is unknown. We have developed a flow cytometry-based method to analyze[unreadable] immune cell content of the mouse aortic wall. We propose to determine why and how atherosclerosis results[unreadable] in chronic inflammation of the vascular wall that does not resolve, and how insulin resistance and type 2[unreadable] diabetes modify this process. Specific aim 1 is to determine the aortic wall content of B, T, and antigen[unreadable] presenting cells in atherosclerotic, insulin resistant and type 2 diabetic mice and pigs. We propose to[unreadable] compare the composition of the aortic walls in apoE-/- mice on chow diet, apoE-/- mice on western diet (insulin[unreadable] resistant), IR+/- IRS1+/- mice (insulin resistant or diabetic, depending on age), and IR+/- IRS1+/- apoE-/- mice[unreadable] (insulin resistant and atherosclerosis-prone) with and without western diet. All these mice are on the[unreadable] C57BL/6 background. Specific aim 2 is to identify the molecular mechanisms by which lymphocytes enter the[unreadable] artery wall in these mouse models of atherosclerosis, insulin resistance, T2D or both. We will use short-term[unreadable] homing assays using fluorescently labeled splenocytes from various knockout mice and long-term homing[unreadable] assays using green fluorescent protein (GFP)-expressing splenocytes. Specific aim 3 is to directly[unreadable] investigate the mechanisms by which lymphocytes interact with the endothelium in carotid and femoral[unreadable] arteries of apoE-/- mice with and without insulin resistance/T2D in vivo. Molecular insights from these[unreadable] intravital microscopy studies and the homing studies described in aim 2 will guide the generation pf double[unreadable] knockout mice and the design of antibody blocking experiments. Disease outcome will be assessed by[unreadable] mapping lesion sizes en face and in cross sections by histology and immunostaining. Together with the other[unreadable] projects described in this PPG renewal application, we expect that our cumulative research will impact the[unreadable] understanding and treatment of diabetic cardiovascular disease.[unreadable]