Abstract 129: Investigation of Atherosclerosis in Association with Arthritic Inflammation

Abstract

Background and Aims It is well established that patients with Rheumatoid Arthritis (RA) have a higher risk of developing coronary artery disease (CAD). However, it is unclear how the inflammatory process affects atherosclerosis and what specific factors are involved. In this study, we investigated the effect of the pro-atherogenic factor hyperlipidaemia on arthritis incidence and severity. Simultaneously, we have investigated the mutation of the neutrophil cytosolic factor 1 (Ncf-1), a known genetic factor that promotes arthritis susceptibility, and MHCII H-2q on atherosclerosis development. Results We observed that diet-induced hyperlipidaemia prior to induction of collagen induced arthritis (CIA) protected mice against the disease while genetically hyperlipidemic without the use of diet, Ldlr-/- x human ApoB100 transgenic (Ldlr-/-hApoBtg), were equally susceptible to CIA compared to their heterozygous littermates. Next, we investigated Ncf-1 mutation on Ldlr-/-hApoBtg mice. Surprisingly, despite the increased inflammatory/arthritic phenotype induced by Ncf-1 mutation, no difference in the atherosclerotic lesion size was observed. Conclusions Our data shows that hyperlipidaemia-induced by diet have substantial effects on arthritis susceptibility, which in turn differs from hyperlipidaemia acquired on birth due to genetic alterations. By developing a model carrying pro-arthritogenic factors, MHCII H-2q and Ncf-1 mutation, as well as the pro-atherosclerotic factors, Ldlr-/- and hApoBtg, we have established a new model where both arthritis and atherosclerosis are present. These mice will be used to further characterize the impact of systemic inflammation in the form of arthritis in the atherosclerotic process and vice versa.