The prevalence of obesity is increasing in the Western society, bringing along an increasing number of complications and health problems. Besides the well-known effects of obesity on cardiovascular function, novel comorbidities related to inflammatory diseases and cancer have been recently described. Although the mechanisms involved in these associations are unclear, there are indications that the elevated levels of free fatty acids in serum of obese individuals could be responsible for the deleterious effects of obesity. Indeed, it has been shown free fatty acids as well as their metabolites can have potent immunomodulatory functions. To understand the mechanisms underlying the association between obesity and inflammatory diseases, it is therefore important to investigate the effects of fatty acids and their metabolites on inflammatory responses and immune cells as such and in relation to rheumatic disease.
In this lecture, evidence indicating a role of lipids and lipid derivatives in inflammatory rheumatic diseases will be presented, with focus on fatty acids and their oxidative products. Recent data indicating the presence of these lipids in inflammatory exudates of rheumatoid arthritis (RA) en osteoarthritis (OA) patients, as well as the effect of these lipid mediators on cells often detected in the inflamed joint of RA and OA patients will be presented. These data indicate that the effector function of macrophages, T cells and fibroblasts can be modulated by various lipids in a potent manner, either towards a more pro- or anti-inflammatory phenotype. The effect depends not only on the cell type investigated, but also on the class of lipids that is studied. All together, the data indicate that lipid mediators could contribute to the inflammatory processes in the arthritic joint, by modulating tissue-resident or infiltrating cells and could be an attractive future therapeutic target.
Disclosure of Interest None declared