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Background: Type 2 diabetes mellitus (T2DM) is an emerging disease in the pediatric population. The association between T2DM and non‐alcoholic fatty liver disease (NAFLD) has been described. Recent evidence suggests that sizes and composition of high‐density lipoprotein (HDL) may be more important that HDL‐C levels in predicting coronary heart disease. There is not data regarding the HDL subclasses distribution and composition in T2DM youths with NAFLD. Methods: This cross‐sectional study included 47 adolescents with T2DM and 23 non‐diabetic controls of both sexes aged 10 to 18 years. The presence of NAFLD was determined estimated proton density fat fraction (PDFF) by magnetic resonance by spectroscopy. We compared the HDL subclasses distribution (HDL2b, HDL2a, HDL3a HDL3b and HDL3c) and the HDL chemical composition (total protein, triglyceride, phospholipid, cholesteryl esters, and free cholesterol) between the groups of adolescents with T2DM and the control group. Results: Patients with T2DM and NAFLD had a significantly lower proportion HDL2b (P =.040) and a higher proportion of HDL3c (P =.035); higher proportion of TG (P =.032) and a lower CE (P =.002) and FC (P <.001). A negative association was observed between PDFF and the percentages of HDL2b (r2 = −0.341, P =.004) and the average particle size (r2 = −0.327, P =.05), and a positive association with HDL3c subpopulations (r2 = 0.327, P =.015); about composition inside HDL particle, a positive association with PDFF and the TG (r2 = 0.299, P =.013) and negative with CE (r2 = −0.265, P =.030). Conclusions: In adolescents diagnosed with T2DM, the presence of NAFLD is associated with abnormalities in the distribution of HDL subpopulations and the lipid composition of HDL particles. [ABSTRACT FROM AUTHOR]

Background Recent evidence suggests that high-density lipoprotein ( HDL) physicochemical characteristics and functional capacity may be more important that HDL-C levels in predicting coronary heart disease. There is little data regarding HDL subclasses distribution in youth with type 1 diabetes. Objective To assess the relationships between glycemic control and HDL subclasses distribution, composition, and function in adolescents with type 1 diabetes. Methods This cross-sectional study included 52 adolescents with type 1 diabetes aged 12-16 years and 43 age-matched non-diabetic controls. Patients were divided into two groups: one in fair control [hemoglobin A1c ( HbA1c) < 9.6%] and the second group with poor glycemic control ( HbA1c ≥ 9.6%). In all participants, we determined HDL subclasses distribution, composition, and the ability of plasma and of isolated HDL to promote cellular cholesterol efflux. Levels of soluble adhesion molecules were also measured. Results Although both groups of patients and the control group had similar HDL-C levels, linear regression analyses showed that compared with non-diabetic subjects, the poor control group had a lower proportion of HDL2b subclass (p = 0.029), triglyceride enriched (p = 0.045), and cholesteryl ester depleted (p = 0.028) HDL particles. Despite these HDL changes, cholesterol efflux was comparable among the three groups. The poor control group also had significantly higher intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 plasma concentrations. Conclusions In adolescents with type 1 diabetes, poor glycemic control is associated with abnormalities in HDL subclasses distribution and HDL lipid composition, however, in spite of these HDL changes, the ability of HDL to promote cholesterol efflux remains comparable to that of healthy subjects. [ABSTRACT FROM AUTHOR]

Alterations in high-density lipoprotein (HDL) subclass distribution, as well as in the activities of HDL-associated enzymes, have been associated with increased cardiovascular disease (CVD) risk. HDL subclass distribution and the activities of HDL-associated enzymes remain unknown in prediabetic patients, a condition also associated with increased CVD risk. The aim of the present study was to assess any differences in HDL subclass distribution (using polyacrylamide gel electrophoresis) and in activities of HDL-associated enzymes between prediabetic (impaired fasting glucose, IFG, n = 80) and non-prediabetic subjects ( n = 105). Subjects with prediabetes had significantly increased waist circumference, blood pressure and triacylglycerol (TAG) levels compared with subjects with fasting glucose levels <100 mg/dL (all p < 0.05). The proportion of small HDL3 over HDL cholesterol (HDL-C) was significantly increased in prediabetic subjects compared with their controls ( p < 0.05). The activity of the anti-atherogenic HDL-associated lipoprotein-associated phospholipase A (HDL-LpPLA) was significantly lower in subjects with prediabetes ( p < 0.05), whereas the activity of paraoxonase 1 (using both paraoxon and phenyl acetate as substrates) did not significantly differ between subjects with or without prediabetes. In a stepwise linear regression analysis, the proportion of small HDL3 over HDL-C concentration was independently associated with the presence of prediabetes and with total cholesterol and TAG concentration (positively), as well as with HDL-C levels (negatively). We also observed a trend of increased small dense low-density lipoprotein cholesterol levels in prediabetic subjects compared with their controls. Subjects with IFG exhibit increased proportion of small HDL3 particles combined with decreased activity of the anti-atherogenic HDL-LpPLA. [ABSTRACT FROM AUTHOR]

Background: Alcohol consumption is associated with increased serum high density lipoprotein (HDL) cholesterol levels and a decreased risk for the development of atherosclerosis. However, the effects of heavy alcohol intake on reverse cholesterol transport, one of the key anti-atherogenic processes related to HDL, are poorly known. Methods: The ability of total HDL as well as HDL2 and HDL3 subclasses to promote cholesterol efflux from 3H-cholesterol-labeled RAW 264.7 macrophages was studied among 6 heavy alcohol drinkers and 6 controls. Distribution of HDL subclasses was analyzed by 4 to 30% native gradient gels. Serum phospholipid transfer protein (PLTP) and cholesteryl ester transfer protein (CETP) activities were analyzed among several other biochemical measures. Results: Cholesterol efflux to HDL2 of heavy drinkers was 22% ( p = 0.025) higher relative to controls. The increase in HDL2 phospholipids, with a concomitant 2-fold ( p = 0.055) increase in large HDL2b particles, was associated with enhanced cholesterol efflux to HDL2. Interestingly, the cholesterol efflux to HDL3 did not differ between the 2 study groups. These findings may be partially explained by a decreased CETP activity (−26%, p = 0.037) and an increased PLTP activity (39%, p = 0.045) in heavy drinkers. Conclusions: The increased cholesterol efflux potential of HDL2 is most likely an anti-atherogenic feature linked to heavy alcohol consumption. The cholesterol efflux and HDL phospholipids also associated strongly within the whole study group ( rs = 0.910, p ≤ 0.01) suggesting a common pathway of enhanced cholesterol efflux via enlarged phospholipid-rich HDL particles. [ABSTRACT FROM AUTHOR]