Serum apolipoprotein profile of patients with chronic renal failure

Serum apolipoprotein profile of patients with chronic renal failure. Serum concentrations of apolipoproteins A-I, A-II, B, C-I, C-II, C-III and E were determined by electroimmunoassay in 56 patients with chronic renal failure (CRF) in the predialytic phase. The results were compared with those obtained in asymptomatic normolipidemic subjects, patients with type IV hyperlipoproteinemia, and patients with type II diabetes mellitus. CRF patients had reduced concentrations of ApoA-I and Apo A-II, normal levels of ApoB and ApoC-I, and increased concentrations of ApoC-II and, in particular, of ApoC-III. There was a significant reduction in the levels of ApoE, especially in male patients. In comparison with type IV, hyperlipoproteinemic patients, CRF patients had lower concentrations of ApoA-I, Apo A-II, ApoB, ApoC-I and, particularly, ApoE; there was no difference in ApoC-III levels reflecting the hypertriglyceridemia common to both disorders. Similar but less marked differences were also found in comparison with type II diabetics. The findings suggest that in CRF, the accumulation of ApoC-III-enriched lipoprotein particles accompanied by a moderate hypertriglyceridemia may be caused more probably by an impaired catabolism than overproduction of triglyceride-rich lipoproteins. CRF patients with vascular disease tended to have higher serum concentrations of triglycerides, cholesterol and ApoB and lower ApoA-I/ApoC-III and ApoA-I/ApoB ratios than patients without vascular disease

Isolation and partial characterization of lipoprotein A-II (LP-A-II) particles of human plasma

High density lipoproteins (HDL) consist of a mixture of chemically and functionally distinct families of particles defined by their characteristic apolipoprotein (Apo) composition. The two major lipoprotein families are lipoprotein A-I (LP-A-I) and lipoprotein A-I : A-II (LP-A-I : A-II). This study describes the isolation of a third minor HDL family of particles referred to as lipoprotein A-II (LP-A-II) because it lacks ApoA-I and contains ApoA-II as its main or sole apolipoprotein constituent. Because ApoA-II is an integral protein constituent of three distinct lipoprotein families (LP-A-I : A-II, LP-A-II : B : C : D : E and LP-A-II), LP-A-II particles were isolated from whole plasma by sequential immunoaffinity chromatography on immunosorbers with antisera to ApoA-II, ApoB and ApoA-I, respectively. In normolipidemic subjects, the concentration of LP-A-II particles, based on ApoA-II content, is 4-18 mg/dl accounting for 5-20% of the total ApoA-II not associated with ApoB-containing lipoproteins. The lipid composition of LP-A-II particles is characterized by low percentages of triglycerides and cholesterol esters and a high percentage of phospholipids in comparison with lipid composition of LP-A-I and LP-A-I : A-II. The major part of LP-A-II particles contain ApoA-II as the sole apolipoprotein constituents; however, small subsets of LP-A-II particles may also contain ApoD and other minor apolipoproteins. The lipid/protein ratio of LP-A-II is higher than those of LP-A-I and LP-A-I : A-II. In homozygous ApoA-I and ApoA-I/ApoC-III deficiencies, LP-A-II particles are the only ApoA-containing high density lipoprotein with levels found to be within the same range (7-13 mg/dl) as those of normolipidemic subjects. However, in contrast to normal LP-A-II, their lipid composition is characterized by higher percentage of triglycerides and cholesterol esters and a lower percentage of phospholipids and their apolipoprotein composition by the presence of ApoC-peptides and ApoE in addition to ApoA-II and ApoD. These results show that LP-A-II particles are a minor HDL family and suggest that, in the absence of ApoA-I-containing lipoproteins, they become an efficient acceptor/donor of ApoC-peptides and ApoE required for a normal metabolism of triglyceride-rich lipoproteins. Their other possible functional roles in lipid transport remain to be established in future experiments.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/29986/1/0000351.pd

Oxidative Stress and Inflammation in Renal Patients and Healthy Subjects

The first goal of this study was to measure the oxidative stress (OS) and relate it to lipoprotein variables in 35 renal patients before dialysis (CKD), 37 on hemodialysis (HD) and 63 healthy subjects. The method for OS was based on the ratio of cholesteryl esters (CE) containing C18/C16 fatty acids (R2) measured by gas chromatography (GC) which is a simple, direct, rapid and reliable procedure. The second goal was to investigate and identify a triacylglycerol peak on GC, referred to as TG48 (48 represents the sum of the three fatty acids carbon chain lengths) which was markedly increased in renal patients compared to healthy controls. We measured TG48 in patients and controls. Mass spectrometry (MS) and MS twice in tandem were used to analyze the fatty acid composition of TG48. MS showed that TG48 was abundant in saturated fatty acids (SFAs) that were known for their pro-inflammatory property. TG48 was significantly and inversely correlated with OS. Renal patients were characterized by higher OS and inflammation than healthy subjects. Inflammation correlated strongly with TG, VLDL-cholesterol, apolipoprotein (apo) C-III and apoC-III bound to apoB-containing lipoproteins, but not with either total cholesterol or LDL-cholesterol

Beef in an Optimal Lean Diet study: effects on lipids, lipoproteins, and apolipoproteins123

Background: A Step I diet with lean beef compared with lean white meat both decrease LDL cholesterol. To our knowledge, no studies have evaluated a low–saturated fatty acid (SFA) (<7% calories) diet that contains lean beef

On the atherogenicity of triglyceride-rich lipoproteins and novel markers for the assessment of their atherogenic potentials

It is generally accepted that cholesterol-rich low density lipoproteins are more significantly associated with atherosclerotic disease than triglyceride-rich very low density lipoproteins. This paper addresses two aspects of the atherogenic potentials of apoB-containing lipoproteins, the first of which relates to the differential atherogenicity of apoB-containing lipoproteins and the second to the adequacy of plasma triglycerides as a marker for atherogenic capacity of triglyceride-rich lipoproteins. These topics are explored and discussed on the basis of the lipoprotein family concept that classifies plasma lipoproteins on the basis of their unique apolipoprotein composition rather than density properties. A brief presentation of the lipoprotein family concept is followed by a review of recent epidemiologic and clinical studies from this and other laboratories showing that some intact or partially delipidized triglyceride-rich lipoproteins possess atherogenic capacities equal, to if not greater than, those of cholesterol-rich lipoproteins. Furthermore, the concept of differential atherogenicity of apoB-containing lipoprotein families is introduced and the evidence is presented that the apoC-III levels associated with apoB-containing lipoproteins are a more consistent independent marker for the atherogenicity of triglyceride-rich lipoproteins than plasma triglycerides