HDL subpopulations containing apoA-I without apoA-II (LpA-I) in patients with angiographically proven coronary artery disease.

BACKGROUND: High density lipoproteins (HDL) can be divided into two metabolically distinct fractions, one containing apolipoprotein (Apo) A-I but not ApoA-II [apolipoprotein A-I; lipoprotein (Lp) A-I] and the other containing both ApoA-I and ApoA-II (LpA-I/A-II). LpA-I fraction which, seeming to be more cardioprotective than LpA-I/A-II particles, is itself heterogeneous. Preß1-HDL is a minor subfraction of LpA-I and the initial acceptor of cellular cholesterol in the process of reverse cholesterol transport. The aim of the study was to determine the usefulness of the determination of LpA-I fractions as indicators for the atherosclerotic process. METHODS: The study included 112 patients with angiographically-documented coronary artery disease (CAD+) and 51 patients with negative results of coronary angiography (CAD-). We evaluated LpA-I concentration in serum in HDL2 and HDL3 fractions as well as Preß1-HDL concentration. Furthermore, we analyzed the association of the assessed parameters with the extent and severity of CAD assessed by Gensini score. RESULTS: CAD+ patients were characterized by a lower concentration of serum LpA-I by 19%, LpA-I in HDL2 by 26%, higher level of Preß1-HDL by 27%, and elevated Preß1-HDL/LpA-I values by 62%. Univariate correlation analysis indicated that serum LpA-I and HDL-cholesterol concentrations were negatively correlated with Gensini score (R=-0.279; p=0.002, R=-0.227; p=0.016, respectively) whereas Preß1-HDL/LpA-I values were positively correlated with the severity of CAD (R=0.529; p<0.001). In multiple linear regression, after adjusting for age, gender, preexisting hypertension, diabetes, and statin therapy, only the Preß1-HDL/LpA-I values remained an independent determinant of atherosclerosis severity (ß=-0.499; p<0.001). CONCLUSIONS: Our results show a lower level of LpA-I and higher concentration of Preß1-HDL in the CAD+ patients compared to the CAD- group. We suggest that the distribution of LpA-I is different in CAD and the Preß1-HDL/LpA-I ratio may have additional value in assessing anti-atherogenic potential of HDL particles and it is likely to become a clinically valuable indicator of atherosclerosis development.

Impact of plant-based diet on lipid risk factors for atherosclerosis.

BACKGROUND: The aim of the study was to investigate the effect of a vegan diet on the serum lipid profile with particular regard to the parameters characterizing the high-density lipoprotein (HDL) fractions in subjects without subclinical atherosclerosis, measured by carotid Doppler ultrasonography. METHODS AND RESULTS: Forty-two 23 to 38 year old subjects (21 omnivores and 21 vegans) participated in the study. Compared to the omnivores, the vegan subjects were characterized by lower parameters of lipid profile: total cholesterol (p < 0.001), low-density lipoprotein (LDL)-cholesterol (p < 0.001), non-HDL-cholesterol (p < 0.001), apolipoprotein B (apoB) (p < 0.001) and phospholipids (p < 0.01). Concentration of HDL-cholesterol was apparently similar between groups. Furthermore, the parameters which characterize HDL particles (con-centration of apolipoproteins AI [apoAI] and AII, HDL-phospholipids, LpAI fraction and pre-b1-HDL fraction) were not significantly different between omnivore and vegan subjects. The apoB/apoAI ratio in vegans was lower than in omnivores (p < 0.01). There was no difference between serum concentration of triacylglycerols between omnivores and vegans. The activity of paraoxonase-1 and 8-iso-prostaglandin F2a concentration were also not different between the study groups. CONCLUSIONS: We suggest that a vegan diet may have a beneficial effect on serum lipid profile and cardiovascular protection, but it is not associated with changes in HDL composition.

PON-1 Activity and Plasma 8-Isoprostane Concentration in Patients with Angiographically Proven Coronary Artery Disease.

The aim of the study was to estimate association of the extent of angiographically proven coronary artery disease (CAD) with plasma 8-isoprostane F2 (8-iso-PGF2α) levels as a reliable marker of lipid peroxidation and serum activity of paraoxonase-1, which demonstrates the ability to protect against lipid oxidation. The study included 105 patients with angiographically documented CAD (CAD+) and 45 patients with negative results of coronary angiography (CAD-). Compared to the control group CAD+ patients were characterized by increased 8-iso-PGF2α levels (P = 0.007) and reduced activity of PON-1 towards paraoxon (PONase, P = 0.002) and phenyl acetate (AREase, P = 0.037). Univariate correlation analysis indicated that 8-iso-PGF2α concentrations were positively associated with the severity of CAD as evaluated by the Gensini score (R = 0.41, P < 0.001) while PONase activity (R = -0.26, P < 0.05) and AREase activity (R = -0.23, P < 0.05) were inversely correlated with CAD severity. PONase activity and 8-iso-PGF2α concentration remained independent determinant of atherosclerosis severity in multiple linear regression after adjusting for age, gender, smoking habits, hypertension, type 2 diabetes, statin therapy, and HDL-C and TAG concentration (ß coefficients -0.267; P < 0.05 and 0.368; P < 0.001, resp.). The results suggest that PON-1 activity and 8-iso-PGF2α concentration are associated with the presence and extent of coronary stenosis and may be considered additional markers of coronary artery disease.

[ApoE-containing HDL and the development of atherosclerosis]. / HDL zawierajace apolipoproteine E a rozwój miazdzycy

The current state of knowledge about the role of high density lipoproteins (HDL) indicates that their anti-atherogenic function is mainly related to the effectiveness of their actions (mostly to the participation in reverse cholesterol transport from tissues to liver) rather than the concentration of HDL itself. HDLs are highly heterogeneous in their structure, lipid and protein composition and metabolic pathways and individual HDL subpopulations differ in their biological activity and effectiveness of anti-atherogenic actions. Apolipoproteins play a key role in HDL metabolism, therefore their presence in lipoproteins is one of the main criterion for HDL classification. According to this criterion HDLs containing apolipoprotein E, called HDL-apoE, are distinguished. Although the anti-atherogenic role of apo E has been demonstrated in many scientific reports, understanding of the mechanisms of formation, transformation and the role of HDL-apoE is still the aim of intense research. The results of epidemiological studies are inconclusive; some of them have demonstrated that high HDL- -apoE concentration has been associated with lower risk of developing coronary heart disease (CHD), while other studies have shown that high levels of HDL-apoE has been an independent risk factor for cardiovascular events and positively correlated with other risk factors for CHD.

[Still's disease or systemic lupus erythematosus in a young adult patient--diagnostic doubts]. / Choroba Stilla czy toczen rumieniowaty ukladowy u mlodego doroslego pacjenta--watpliwosci diagnostyczne.

Systemic lupus erythematosus and Still's disease are chronic autoimmune disorders of unknown etiology. Symptomatology of these diseases may be similar causing diagnostic difficulties. Long-term observation and immunological studies are essential to identify the definite disorder. We present a case of a 24-year-old patient with high fever, sore throat and arthritis. During hospitalization rash accompanying fever, nodular erythema, pulmonary changes, liver damage and splenomegaly were observed. Although initially adult-onset Still's disease was diagnosed according to the Yamaguchi criteria, the diagnosis of systemic lupus erythematosus was made after re-analysis of the clinical course and immunological tests.