Autoantibodies to oxidized low-density lipoprotein in patients with aortic regurgitation: association with aortic diameter size

Increased Concentrations of Atherogenic Proteins in Aneurysm Sac Are Associated with Wall Enhancement of Unruptured Intracranial Aneurysm

Current MR-vessel wall imaging (VWI) of unruptured intracranial aneurysms (UIAs) permits the visualization of wall structures. Aneurysm wall enhancement (AWE) was associated with atherosclerotic remodeling of the aneurysm wall accompanied by infiltration of inflammatory cells, potentially contributing to rupture. This study sought to investigate whether the luminal concentrations of atherosclerotic proteins in the aneurysm sac were associated with increased wall enhancement of UIAs in VWI. Subjects undergoing endovascular treatment for UIAs were prospectively recruited. All subjects underwent evaluation using 3 T-MRI including pre/post contrast VWI of the UIAs. Blood samples were collected from the aneurysm sac and the parent artery during endovascular procedures. The presence of AWE was correlated with the delta difference in concentration between the aneurysm sac and the parent artery for each atherosclerotic protein. A total of consecutive 45 patients with 50 UIAs were enrolled. The delta differences of anti-oxidized low-density lipoprotein (LDL) antibody, small dense LDL, and lipoprotein(a) [Lp(a)] were significantly higher in UIAs with AWE compared with those without AWE (767.6 ± 1957.1 versus - 442.4 ± 1676.3 mIU/mL, p = 0.02, 114.8 ± 397.7 versus - 518.5 ± 1344.4 μg/mL, p = 0.04, and - 5.6 ± 11.3 versus - 28.7 ± 38.5 μg/mL, p = 0.01, respectively). In multivariate logistic regression analysis, the delta Lp(a) was significantly associated with AWE (p = 0.04). Increased concentrations of atherogenic proteins in the aneurysm sac were significantly associated with wall enhancement of UIAs. Future studies examining the effect of medications for atherosclerosis on the atherogenic proteins within the aneurysm sac and hence the wall enhancement are warranted.

Autoimmune Rheumatic Diseases and Vascular Function: The Concept of Autoimmune Atherosclerosis

Autoimmune rheumatic diseases (AIRDs) with unknown etiology are increasing in incidence and prevalence. Up to 5% of the population is affected. AIRDs include rheumatoid arthritis, system lupus erythematosus, systemic sclerosis, and Sjögren's syndrome. In patients with autoimmune diseases, the immune system attacks structures of its own body, leading to widespread tissue and organ damage, which, in turn, is associated with increased morbidity and mortality. One third of the mortality associated with autoimmune diseases is due to cardiovascular diseases. Atherosclerosis is considered the main underlying cause of cardiovascular diseases. Currently, because of finding macrophages and lymphocytes at the atheroma, atherosclerosis is considered a chronic immune-inflammatory disease. In active inflammation, the liberation of inflammatory mediators such as tumor necrotic factor alpha (TNFa), interleukine-6 (IL-6), IL-1 and other factors like T and B cells, play a major role in the atheroma formation. In addition, antioxidized, low-density lipoprotein (LDL) antibodies, antinuclear antibodies (ANA), and rheumatoid factor (RF) are higher in the atherosclerotic patients. Traditional risk factors like gender, age, hypercholesterolemia, smoking, diabetes mellitus, and hypertension, however, do not alone explain the risk of atherosclerosis present in autoimmune diseases. This review examines the role of chronic inflammation in the etiology-and progression-of atherosclerosis in autoimmune rheumatic diseases. In addition, discussed here in detail are the possible effects of autoimmune rheumatic diseases that can affect vascular function. We present here the current findings from studies that assessed vascular function changes using state-of-the-art techniques and innovative endothelial function biomarkers.

Elevated oxidative stress in the aortic media of patients with bicuspid aortic valve

OBJECTIVE

Congenital bicuspid aortic valve (BAV) is distinctly associated with the development of ascending aortopathy in adulthood, portending risk of both ascending aortic aneurysm and dissection. Our previous work implicated deficiency in oxidative stress response as a mediator of the BAV-associated aortopathy. We hypothesize that reactive oxygen species generation invokes elevated local oxidative tissue damage in ascending aorta of patients with BAV.

METHODS

Ascending aortic specimens were obtained from patients undergoing elective aortic replacement and/or aortic valve replacement and during heart transplant operations. Levels of superoxide anion were measured via high-pressure liquid chromatography-based detection of 2-hydroxyethidium in aortic specimens. Lipid peroxidation and enzymatic activity of superoxide dismutase and peroxidase were quantified in aortic specimens.

RESULTS

Superoxide anion production was elevated in aortic specimens from patients with nonaneurysmal BAV (n = 59) compared with specimens from patients with the morphologically normal tricuspid aortic valve (TAV, n = 38). Total superoxide dismutase activity was similar among aortic specimens from patients with TAV versus BAV (n = 27 and 26, respectively), whereas peroxidase activity was increased in aortic specimens from patients with BAV compared with specimens from patients with TAV (n = 14 for both groups). Lipid peroxidation was elevated in aortic specimens from BAV patients compared with TAV patients (n = 14 and 11, respectively).

CONCLUSIONS

Superoxide anion accumulation and increased lipid peroxidation demonstrate that, despite increased peroxidase activity, the ascending aortopathy of patients with BAV involves oxidative stress. In addition, the absence of increased superoxide dismutase activity in BAV specimens indicates a deficiency in antioxidant defense. This suggests that the characteristic smooth muscle cell loss observed in BAV aortopathy may be a consequence of superoxide-mediated cell damage.

Usefulness of Antibodies to Oxidized Low-Density Lipoproteins as Predictors of Morbidity and Prognosis in Heart Failure Patients Aged ≥65 Years

Elevated level of antibodies to oxidized low-density lipoproteins (OxLDL-Ab) was shown to reliably predict morbidity and mortality in patients with heart failure (HF). Two hundred and eleven patients aged ≥65 years treated at the Heart Failure Unit, Tel Aviv-Sourasky Medical Center, were included in this retrospective study. The end points were time to the first hospitalization (morbidity), all-cause mortality, and a combination of the two (composite outcome). HF duration ranged from 8 to 10.5 years. Mean follow-up was 5.2 ± 1.9 years. The mean number of clinical visits was 18.3 ± 2.4. Participants were divided according to OxLDL-Ab level. Group 1 had Ox LDL-Ab level <200 arbitrary U/ml. Group 2 had OxLDL-Ab level ≥200 arbitrary U/ml. The mean time to the first hospitalization was 25.8 ± 17.0 months. The mortality rate was 44.1%. Combined mortality and hospitalization rate was 58.8%. Adjusted hazard ratios of OxLDL-Ab for hospitalization were 3.16, p <0.001, 95% confidence interval 1.740 to 5.736 and for composite outcome 2.67, p <0.001, 95% confidence interval 1.580 to 4.518. In conclusion, OxLDL-Ab level was the best predictor for both hospitalization and composite outcome. It may, thus, serve as a useful clue for early and more accurate detection of poorly controlled HF and as a marker for imminent exacerbations of thereof.