Dataset Information

Low-density lipoprotein is the major carrier of lipid hydroperoxides in plasma. Relevance to determination of total plasma lipid hydroperoxide concentrations.

ABSTRACT: High-density lipoprotein (HDL) has been proposed as the principal carrier of hydroperoxides in plasma, based upon data gathered with an HPLC-chemiluminescence technique. To test this hypothesis we have measured total lipid hydroperoxides in native plasma using the ferrous oxidation in Xylenol Orange (FOX) assay and then fractionated plasma into very-low-density lipoprotein (LDL) and HDL fractions. Hydroperoxides were found to accumulate principally (more than 65%) in LDL, as judged by hydroperoxide content per amount of protein or cholesterol, or expressed as a proportion of total hydroperoxide in plasma. Plasma was also incubated at 37 degrees C in the presence and absence of 2,2'-azo-bis-(2-amidinopropane) hydrochloride (AAPH), an azo-initiator of lipid peroxidation. The majority of hydroperoxides generated in plasma were recovered in the LDL fraction. Furthermore, when isolated lipoproteins were subject to oxidation initiated by AAPH, very-low-density lipoprotein and LDL showed the greatest propensity for hydroperoxide accumulation, whereas HDL seemed relatively resistant. Estimates for plasma and LDL peroxidation based upon techniques which measure total lipid hydroperoxides suggest that levels of hydroperoxides in plasma and LDL are far higher than that those estimates generated by ostensibly more selective techniques. Higher levels of hydroperoxides in LDL than those reported by HPLC-chemiluminescence also seem in greater accordance with other available data concerning LDL oxidation.

SUBMITTER: Nourooz-Zadeh J

PROVIDER: S-EPMC1216978 | biostudies-other | 1996 Feb

REPOSITORIES: biostudies-other

ACCESS DATA

Similar Datasets

Project description:BackgroundProspective cohort studies have found a relation between sugar-sweetened beverage consumption (SSB; sodas and fruit drinks) and dyslipidemia. There is limited evidence linking SSB consumption to emerging features of dyslipidemia, which can be characterized by variation in lipoprotein particle size, remnant-like particle (RLP), and apolipoprotein concentrations.ObjectiveTo examine the association between SSB consumption and plasma lipoprotein cholesterol, apolipoprotein, and lipoprotein particle size concentrations among US adults.MethodsWe examined participants from the Framingham Offspring Study (FOS) (1987-1995; n = 3047) and the Women's Health Study (1992; n = 26,218). Plasma LDL-C, apolipoprotein (apo) B, HDL-C, apoA1, triglyceride (TG), non-HDL-C, total: HDL-cholesterol ratio, and apoB: apoA1 concentrations were quantified in both cohorts, and apoE, apoC3, RLP-TG, and RLP-cholesterol concentrations in FOS only. Lipoprotein particle sizes were calculated from NMR signals for lipoprotein particle subclass concentrations (triglyceride-rich lipoprotein particles [TRL-P; very large, large, medium, small, and very small], LDL-particles [LDL-P; large, medium, and small], HDL-particles [HDL-P; large, medium, and small]). SSB consumption was estimated from food frequency questionnaire data. We examined the associations between SSB consumption and all lipoprotein and apoprotein measures in linear regression models, adjusting for confounding factors, such as lifestyle, diet, and traditional lipoprotein risk factors.ResultsSSB consumption was positively associated with LDL-C, apoB, TG, RLP-TG, RLP-C, non-HDL-C concentrations and total: HDL cholesterol and apoB: apoA1 ratio, and negatively associated with HDL-C and apoA1 concentrations (P-trend ranges from < 0.0001 to 0.003). After adjustment for traditional lipoprotein risk factors, SSB consumers had smaller LDL-P and HDL-P sizes, lower concentrations of large LDL-P and medium HDL-P, and higher concentrations of small LDL-P, small HDL-P, and large TRL-P (P-trend ranges from < 0.0001 to 0.0009).ConclusionsHigher SSB consumption was associated with multiple emerging features of dyslipidemia that have been linked to higher cardiometabolic risk in US adults.

Project description:Background: High intakes of trans-fatty acids (TFAs), especially industrially produced TFAs, can lead to unfavorable lipid and lipoprotein concentrations and an increased risk of cardiovascular disease. It is unknown how this relation might change in a population after significant reductions in TFA intake.Objective: This study, which used a new analytical method for measuring plasma TFA concentrations, clarified the association between plasma TFA and serum lipid and lipoprotein concentrations before and after the US FDA enacted TFA food-labeling regulations in 2006.Methods: Data were selected from the NHANES of 1999-2000 and 2009-2010. Findings on 1383 and 2155 adults, respectively, aged ≥20 y, were evaluated. Multivariable linear regressions were used to examine the associations between plasma TFA concentration and lipid and lipoprotein concentrations. The outcome measures were serum concentrations of total cholesterol (TC), LDL cholesterol, HDL cholesterol, and triglycerides and the ratio of TC to HDL cholesterol.Results: The median plasma TFA concentration decreased from 80.6 μmol/L in 1999-2000 to 37.0 μmol/L in 2009-2010. Plasma TFA concentration continued to be associated with serum lipid and lipoprotein concentrations after significant reductions in TFA intake in the population. For example, by comparing the lowest with the highest quintiles of TFA concentration in 1999-2000, adjusted mean (95% CI) LDL-cholesterol concentrations increased from 118 mg/dL (112, 123 mg/dL) to 135 mg/dL (130, 141 mg/dL) (P-trend < 0.001). The corresponding values for 2009-2010 were 102 mg/dL (97.4, 107 mg/dL) and 129 mg/dL (125, 133 mg/dL) for LDL cholesterol (P-trend < 0.001). Differences between the highest and lowest quintiles were consistent across age groups, sexes, races/ethnicities, and other covariates.Conclusions: Despite a 54% reduction in plasma TFA concentrations in US adults from 1999-2000 to 2009-2010, concentrations remained significantly associated with serum lipid and lipoprotein concentrations. There does not appear to be a threshold under which the association between plasma TFA concentration and lipid profiles might become undetectable.

Dataset Information

Low-density lipoprotein is the major carrier of lipid hydroperoxides in plasma. Relevance to determination of total plasma lipid hydroperoxide concentrations.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets