A tale of two plaques: convergent mechanisms of T-cell-mediated inflammation in psoriasis and atherosclerosis.

Psoriasis and atherosclerosis are diseases in which effector T lymphocytes such as Helper T cells type 1 (Th1) and 17 (Th17) play integral roles in disease pathogenesis and progression. Regulatory T cells (Treg) also exert clinically important anti-inflammatory effects that are pathologically altered in psoriasis and atherosclerosis. We review the immunological pathways involving Th1, Th17 and Treg cells that are common to psoriasis and atherosclerosis. These shared pathways provide the basis for mechanisms that may explain the epidemiologic observation that patients with psoriasis have an increased risk of heart disease. Improved understanding of these pathways will guide future experiments and may lead to the development of therapeutics that prevent or treat cardiovascular complications in patients with psoriasis.

Angiogenesis and oxidative stress: common mechanisms linking psoriasis with atherosclerosis.

Shared angiogenic and oxidative mechanisms underlie the pathophysiology of psoriasis and atherosclerosis. During the pathogenesis of both diseases, stimuli such as injury or local hypoxia trigger the release of pro-angiogenic factors including IL-8, HIF-1α, ETS-1, and VEGF. These factors stimulate increased permeability and encourage leukocyte transmigration into areas of inflammation by enhanced expression of cell adhesion molecules. Psoriasis and atherosclerosis also share common enzymatic sources of reactive oxygen species (ROS), and these ROS influence several cellular signaling pathways implicated in the pathogenesis of both diseases. Pharmacologic and genetic therapies that target key factors in these pathways could provide innovative approaches to the management of psoriasis and potentially mitigate the cardiovascular complications suffered by psoriasis patients.