Semaglutide reduces vascular inflammation investigated by PET in a rabbit model of advanced atherosclerosis

• DOI: 10.1016/j.atherosclerosis.2022.03.032
• Publication Date: 2022-04-04T14:57:37Z
• Authors: Jacob K. Jensen; Tina Binderup; Constance E. Gran...; Simon Bentsen; Rasmus S. Ripa; Andreas Kjaer
• Keywords: Inflammation; Glucagon-Like Peptides; Molecular imaging; Calcinosis; Atherosclerosis; Article; 3. Good health; 03 medical and health sciences; PET; 0302 clinical medicine; Fluorodeoxyglucose F18; Positron Emission Tomography Computed Tomography; Positron-Emission Tomography; Animals; Rabbits; Radiopharmaceuticals; GLP-1; Radionuclide Imaging

The objective of this study was to investigate the effects of semaglutide, a long acting glucagon-like peptide-1 receptor agonist, on atherosclerotic inflammation and calcification using a multimodality positron emission tomography and computed tomography (PET/CT) approach.Atherosclerotic New Zealand White rabbits were randomized to an intervention- (n = 12) or placebo group (n = 11) receiving either semaglutide or saline-placebo. PET/CT imaging was done before and after 16-weeks of intervention. Three different radiotracers were used: [64Cu]Cu-DOTATATE for imaging of activated macrophages, [18F]FDG imaging cellular metabolism and [18F]NaF PET visualizing micro-calcifications. Tracer uptake was quantified by maximum standardized uptake value (SUVmax) and target-to-background-ratio (TBRmax). Animals were euthanized for autoradiographic imaging and histological analyses.A reduction in activated macrophage tracer-uptake was observed in the semaglutide group (SUVmax: p = 0.001 and TBRmax: p = 0.029). When imaging cellular metabolism, an attenuation of SUVmax and TBRmax was observed in the semaglutide group (p = 0.034 and p = 0.044). We found no difference in uptake of the micro-calcification tracer between the two groups (SUVmax: p = 0.62 and TBRmax: p = 0.36). Values of macrophage density in the vessel wall were significantly correlated with SUVmax values of the activated macrophage (r = 0.54, p = 0.0086) and cellular metabolism tracers (r = 0.51, p = 0.013).Semaglutide decreased vascular uptake of tracers imaging activated macrophages and cellular metabolism but not micro-calcifications compared to a saline placebo. This supports the hypothesis that semaglutide reduces atherosclerotic inflammation by means of decreased activated macrophage activity.