CKD potentiates macrophage infiltration into the vessel wall by increasing the expression of vascular adhesion molecules (VCAM1, ICAM1 and selectins) and chemoattractants (CCL2 and MCSF)

CKD potentiates macrophage infiltration into the vessel wall by increasing the expression of vascular adhesion molecules (VCAM1, ICAM1 and selectins) and chemoattractants (CCL2 and MCSF). system in the enhanced susceptibility to atherosclerosis seen across the spectrum of CKD. The role of macrophages could explain why these therapies may be effective in end-stage renal disease, one of the few conditions in which statins show no clinical benefit. Introduction More than 50% of deaths in patients with chronic kidney disease (CKD) on dialysis are attributable to cardiovascular disease.1 even modest renal dysfunction, including isolated albuminuria, results in a dramatic increase in the risk of cardiovascular disease.2C5 the relationship between decreasing renal function and increasing 10058-F4 rates of cardiovascular disease and mortality is due to multiple mechanisms, including abnormal myocardial remodeling, ventricular hypertrophy, arrhythmia and cardiac arrest; the influence of these factors depends on the level of CKD. Compared with the prevalence of atherosclerotic disease in individuals with intact kidney function, however, atherosclerotic disease is over- represented across the entire spectrum of patients with CKD. macrophages have critical roles in all stages of atherosclerotic lesion formation and mounting experimental evidence implicates their importance in the vascular complications of renal disease. Macrophages contribute to all stages of atherosclerosis through their role in inflammation and lipid homeostasis.6 retention of atherogenic lipoproteins in the arterial intima prompts the production of leukocyte chemo-attractant molecules. these molecules activate receptors on rolling monocytes, which leads to their initial adhesion mediated by selectins, followed by their integrin-dependent adhesion to the endothelium and their, subsequent diapedesis into the intima.7 Chemokines (chemotactic cytokines) and their receptors have been implicated in the migration of monocytes and t cells into the arterial intima.8 the critical role for macrophages in the development of atherosclerosis is illustrated by the observation that osteopetrotic mice, which lack macro-phage colony-stimulating factor, have low numbers of macrophages in their atherosclerotic lesions and a small lesion area, even in the presence of severe hyper-lipidemia. 9 macrophages also have a central role in innate immunity.10 the interaction between antigen-presenting dendritic cells and T cells activates the adaptive immune response and defines the inflammatory processes of early atherogenesis. ligation of CD40 on activated Tt cells leads to enhanced production of T helper (TH) 1 cell cytokines, including interferon ,11 which is proatherogenic.12 this TH1 cytokine cascade is counterbalanced by the presence of antiatherogenic TH2 cytokines, including 10058-F4 interleukin (il)-10.13 this review focuses on the mechanisms of CKD-induced 10058-F4 atherosclerosis, with particular emphasis on the role of macrophages, as demonstrated by experimental studies and data 10058-F4 from clinical studies. Macrophages and atherosclerosis The accumulation of macrophages laden with cholesterol ester in the arterial intima is the hallmark of fatty streak formation in humans and experimental models. macrophages internalize atherogenic lipoproteins (such as oxidized lDl) via scavenger receptors, including CD3614 and class a scavenger receptors (SR-A).15,16 native lipoprotein receptors, such as the LDL receptor-related protein 1,17 will also be indicated by macrophages and contribute to atherogenesis. Cholesterol access into macrophages is definitely counterbalanced from the efflux of free cholesterol into acceptor particles (such as HDL).18 Free cholesterol efflux is mediated by active trans porters, such as ATP-binding cassette sub family a member 1 (ABCA1), ATP-binding cassette subfamily G member 1 (ABCG1) and scavenger receptor class Rabbit polyclonal to CCNA2 B member i (SR-BI), or by passive diffusion.19 an study of isolated mouse macrophages shown that abca1 mediates the efflux of free cholesterol and phospholipids to both apo-lipoprotein A-1 (Apoa1) and apolipoprotein E (Apoe).20 Apoe is abundantly indicated by macrophages in atherosclerotic lesions,21 might represent the physiological acceptor of cholesterol in atherosclerotic plaques,20 and is strongly antiatherogenic.21,22 macrophages and/or dendritic cells will also be capable of leaving the atherosclerotic plaque, as a result promoting regression of atherosclerosis in murine models. Gene manifestation profiles of regressing atherosclerotic plaques have linked CC-chemokine receptor (CCR) 7 with dendritic cell emigration, and antibody-blocking experiments in mice have confirmed that CCR7 causes macrophage emigration and plaque regression. 23 Macrophages also influence atherogenesis through their susceptibility to death. endoplasmic reticulum stress is a major inducer of macrophage apoptosis24,25 and, whereas macrophage apoptosis in the early phases of atherogenesis might.