Search

Inflammation is critical to atherogenesis. Psoriasis is a chronic inflammatory skin disease that accelerates atherosclerosis in humans and provides a compelling model to understand potential pathways linking these diseases. A murine model capturing the vascular and metabolic diseases in psoriasis would accelerate our understanding and provide a platform to test emerging therapies. We aimed to characterize a new murine model of skin inflammation (Rac1V12) from a cardiovascular standpoint to identify novel atherosclerotic signaling pathways modulated in chronic skin inflammation. The RacV12 psoriasis mouse resembled the human disease state, including presence of systemic inflammation, dyslipidemia, and cardiometabolic dysfunction. Psoriasis macrophages had a proatherosclerotic phenotype with increased lipid uptake and foam cell formation, and also showed a 6-fold increase in cholesterol crystal formation. We generated a triple-genetic K14-RacV12-/+/Srb1-/-/ApoER61H/H mouse and confirmed psoriasis accelerates atherogenesis (~7-fold increase). Finally, we noted a 60% reduction in superoxide dismutase 2 (SOD2) expression in human psoriasis macrophages. When SOD2 activity was restored in macrophages, their proatherogenic phenotype reversed. We demonstrate that the K14-RacV12 murine model captures the cardiometabolic dysfunction and accelerates vascular disease observed in chronic inflammation and that skin inflammation induces a proatherosclerotic macrophage phenotype with impaired SOD2 function, which associated with accelerated atherogenesis.

Inflammation is known to play a significant role in the process of atherogenesis and cardiovascular disease (CVD). Indeed, patients with chronic inflammatory diseases are at increased risk for cardiovascular events. However, the mechanisms linking chronic inflammation and CVD remain poorly understood. Psoriasis, a chronic inflammatory skin disease associated with a greater risk of early cardiovascular events, provides a suitable human model to study the pathophysiology of inflammatory atherogenesis in humans. Additionally, cytokines such as TNF-α, IL-17A, and other immune pathways are the common links between the pathogenesis of psoriasis and atherosclerosis, and hence the approved treatments for psoriasis, which include selective cytokine inhibition (e.g., anti-TNF, anti-IL-17A, and anti-IL-12/23) and immune modulation (e.g., methotrexate or cyclosporine), provide an opportunity to examine the effect of modulating these pathways on atherogenesis. We have been using this human model in a large, prospective cohort study, and this review summarizes our approach and results of using this human model to study inflammatory atherogenesis. Specifically, we review simultaneous multimodal imaging of several vascular beds using 18 fludeoxyglucose positron emission tomography/computed tomography, 18 fludeoxyglucose positron emission tomography/MRI, and coronary computed tomography angiography as well as cardiovascular biomarkers to better understand how modulation of inflammation may impact vascular diseases.