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In rheumatoid arthritis (RA), the risk of cardiovascular death is 50% higher compared to the general population. This increased risk is partly due to the systemic inflammation characteristic of RA and changes in the lipoprotein profiles. This study investigated plasma lipid levels, lipid ratios, and the composition and functionality of high-density lipoprotein (HDL) in control individuals and RA subjects based on the disease's inflammatory score (DAS28). This study included 50 control (CTR) individuals and 56 subjects with RA, divided into remission/low-activity disease (DAS28 < 3.2; n = 13) and active disease (DAS28 ≥ 3.2; n = 43). Plasma lipids (total cholesterol, TC; triglycerides, TG) and the HDL composition (TC; TG; phospholipids, PL) were determined using enzymatic methods; apolipoprotein B (apoB) and apoA-1 were measured by immunoturbidimetry. HDL-mediated cholesterol efflux and anti-inflammatory activity were assessed in bone marrow-derived macrophages. Comparisons were made using the Mann-Whitney test, and binary logistic regression was used to identify the predictors of active RA. A p -value < 0.05 was considered significant. TC, HDLc, and the TC/apoB ratio were higher in RA subjects compared to the CTR group. Subjects with active disease exhibited higher levels of TG and the TG/HDLc ratio and lower levels of HDLc, the TG/apoB ratio, TC, and apoA-1 in HDL particles compared to those with remission/low-activity RA. Increased levels of HDLc [odds ratio (OR) 0.931, 95% CI = 0.882-0.984], TC/apoB (OR 0.314, 95% CI = 0.126-0.78), HDL content in TC (OR 0.912, 95% CI = 0.853-0.976), PL (OR 0.973, 95% CI = 0.947-1.000), and apoA-1 (OR 0.932, 95% CI = 0.882-0.985) were associated with a decreased risk of active disease, but BMI (OR 1.169, 95% CI = 1.004-1.360) and TG (OR 1.031, 95% CI = 1.005-1.057) were positively associated with active disease. A reduction in HDL-mediated cholesterol efflux increased the OR for active RA by 26.2%. The plasma levels of HDLc, along with the composition and functionality of HDL, influence the inflammatory score in RA and may affect the development of cardiovascular disease.

Advanced glycation end products (AGEs) prime macrophages for lipopolysaccharide (LPS)-induced inflammation. We investigated the persistence of cellular AGE-sensitization to LPS, considering the nuclear content of p50 and p65 nuclear factor kappa B (NFKB) subunits and the expression of inflammatory genes. Macrophages treated with control (C) or AGE-albumin were rested for varying intervals in medium alone before being incubated with LPS. Comparisons were made using one-way ANOVA or Student t -test ( n = 6). AGE-albumin primed macrophages for increased responsiveness to LPS, resulting in elevated levels of TNF, IL-6, and IL-1beta (1.5%, 9.4%, and 5.6%, respectively), compared to C-albumin. TNF, IL-6, and IL-1 beta secretion persisted for up to 24 h even after the removal of AGE-albumin (area under the curve greater by 1.6, 16, and 5.2 times, respectively). The expressions of Il6 and RelA were higher 8 h after albumin removal, and Il6 and Abca1 were higher 24 h after albumin removal. The nuclear content of p50 remained similar, but p65 showed a sustained increase (2.9 times) for up to 24 h in AGE-albumin-treated cells. The prolonged activation of the p65 subunit of NFKB contributes to the persistent effect of AGEs on macrophage inflammatory priming, which could be targeted for therapies to prevent complications based on the AGE-RAGE-NFKB axis.