Association between ethnicity and obesity with high-density lipoprotein (HDL) function and subclass distribution

Abstract

BackgroundObesity and low high-density lipoprotein-cholesterol (HDL-C) levels are associated with cardiovascular risk. Surprisingly, despite a greater prevalence of obesity and lower HDL concentrations than white women, black South African women are relatively protected against ischaemic heart disease.MethodsWe investigated whether this apparent discrepancy may be related to different HDL function and subclass distribution in black and white, normal-weight and obese South African women (n = 40). HDL functionality was assessed by measuring paraoxonase (PON) activity, platelet activating factor acetylhydrolase (PAF-AH) activity, Oxygen Radical Absorbance Capacity (ORAC) and quantification of the expression of vascular cell adhesion molecule in endothelial cells. PON-1 and PAF-AH expression was determined in isolated HDL and serum using Western blotting. Levels of large, intermediate and small HDL subclasses were measured using the Lipoprint® system.ResultsPON activity was lower in white compared to black women (0.49 ± 0.09 U/L vs 0.78 ± 0.10 U/L, p < 0.05), regardless of PON-1 protein levels. Obese black women had lower PAF-AH activity (9.34 ± 1.15 U/L vs 13.89 ± 1.21 U/L, p <0.05) and HDL-associated PAF-AH expression compared to obese white women. Compared to normal-weight women, obese women had lower large HDL, greater intermediate and small HDL; an effect that was more pronounced in white women than black women. There were no differences in antioxidant capacity or anti-inflammatory function across groups.ConclusionsOur data show that both obesity and ethnicity are associated with differences in HDL functionality, while obesity was associated with decreases in large HDL subclass distribution. Measuring HDL functionality and subclass may, therefore, be important factors to consider when assessing cardiovascular risk.Electronic supplementary materialThe online version of this article (doi:10.1186/s12944-016-0257-9) contains supplementary material, which is available to authorized users.

Influence of i.v. lipid emulsion on lipoprotein subclass in preterm infants

“…Recently, the measurement of lipid contents in different lipoprotein subclasses has been recognized to be useful for the assessment of lipid metabolism . In adults, lipid levels in certain lipoprotein subclasses are associated with cardiovascular disease and metabolic disease . In young adults who were born preterm at very low‐birthweight, the concentration of triglyceride in the largest VLDL and of triglyceride in small HDL particles were higher than in individuals of the same age who were of average birthweight .…”

“…With regard to HDL particle size, previous research has indicated that obesity is associated with a decrease in the proportion of large HDL subclass, which may increase the risk of cardiovascular disease . Furthermore, the smaller HDL subclasses, which more closely correlate with HDL function and confer less risk of cardiovascular disease, are important markers of residual mortality risk for cardiovascular disease .…”

“…10,11 In adults, lipid levels in certain lipoprotein subclasses are associated with cardiovascular disease and metabolic disease. [13][14][15] In young adults who were born preterm at very low-birthweight, the concentration of triglyceride in the largest VLDL and of triglyceride in small HDL particles were higher than in individuals of the same age who were of average birthweight. 12 Preterm infants, many of whom are VLBW, have an increased risk for cardiovascular disease in adulthood, 16 and suboptimal nutrition, including suboptimal lipid nutrition, in the prenatal and postnatal periods may be one of the causes.…”

Protection from Cardiovascular Disease Due to Increased High-Density Lipoprotein Cholesterol in African Black Populations: Myth or Reality?

“…80 In addition, obese women had decreased levels of large HDL compared with their normal-weight counterparts. 80 These preliminary data indicate the importance of a -Woudberg et al focussed approach on HDL subclass and functionality, which may provide further novel insights into CVD risk in African populations.…”

Establishing reference values and evaluation of an in-house ferric reducing antioxidant power (FRAP) colorimetric assay in microplates

“…Several methods have been developed to measure TAC, and the most common of these methods are the oxygen radical absorbance capacity (ORAC), ferric reducing antioxidant power (FRAP) and the total radical trapping antioxidant potential (TRAP) [5][6][7]. A FRAP spectrophotometric assay can be performed using the method developed by Benzie and Strain [8].…”