Madison Engel
Research Mentor(s): Jason Knight
Mentor Department: Internal Medicine/Rheumatology
Authors: Madison Engel, Chao Liu, Maya Barnabas, Lucas Hudgins, Bavani Vijay, Jason Knight, Sri Yalavarthi
Session: Session 3 (11:00am – 11:50am)
Presentation Type: Poster 94
Abstract
Neutrophil extracellular traps (NETs) are web-like DNA structures released by neutrophils to combat infections. NET formation can also be triggered by non-infectious stimuli, including high glucose levels. Our team previously found that NETs induce endothelial dysfunction in diabetic mice, which is known to increase the risk for future atherosclerosis. This follow-up study investigated whether the inhibition of NET formation would reduce atherosclerotic plaque formation in mice with diabetes. Aortic plaque formation was characterized in four groups of mice: Akita (diabetic mice), wildtype (healthy control mice), Akita-neutrophil elastase (NE) knockout mice, and Akita-Pad4 knockout mice (both groups of knockout mice are known to be NET-deficient). All four groups received AAV-Pcsk9 and a 43% high-fat diet to establish the atherosclerosis phenotype. After twelve weeks, the mice (n=8) were tested for plaque formation. Specifically, the aortae were stained using Oil Red ‘O’, pinned to a wax dish, and photographed. In a parallel experiment, the aortae from n=2 mice/group were digested to prepare a single-cell suspension for single-cell RNA sequencing. In addition to harvesting the aortae, the liver, heart, and plasma were also stored for future analyses. Compared with wild-type mice, Akita mice demonstrated significantly more plaque formation (23% versus 2.5%, p=<0.001). At the same time, when compared with Akita mice, the atherosclerotic burden was reduced to 5% and 6% in Akita-NE knockout mice and Akita-Pad4 knockout mice, respectively. Analysis of the single-cell RNA sequencing dataset is underway in pursuit of identifying differences in gene expression that might explain the mechanism underlying the role of NETs in diabetes-associated plaque formation. In summary, the reduction of NET formation in Akita-NE and Akita-Pad4 knockout mice likely explains their reduced plaque formation compared with the Akita mice. Inhibition of either NE or PAD4 might be novel ways to reduce the burden of atherosclerosis in patients with diabetes. Furthermore, the transcriptomic profiling that is underway is likely to identify other therapeutic targets.
