Glucosamine-induced endoplasmic reticulum (ER) stress was recently shown to specifically reduce apolipoprotein B-100 (apoB-100) secretion by enhancing the proteasomal degradation of apoB-100. Here, we examined the mechanisms linking glucosamine-induced ER stress and apoB-lipoprotein biogenesis. Trypsin sensitivity studies suggested glucosamine-induced changes in apoB-100 conformation. Endoglyco...

BACKGROUND Familial hypercholesterolemia (FH), a major risk for coronary heart disease, is predominantly associated with mutations in the genes encoding the low-density lipoprotein receptor (LDLR) and its ligand apolipoprotein B (APOB). RESULTS In this study, we characterize the spectrum of mutations causing FH in 2239 Czech probands suspected to have FH. In this set, we found 265 patients (1...

BACKGROUND Oxidized phospholipids (OxPL) are present within atherosclerotic plaques and bound by lipoprotein (a) [Lp(a)] in plasma. This study evaluated the impact of atorvastatin on oxidized LDL (OxLDL) in patients with acute coronary syndromes (ACS). METHODS AND RESULTS OxLDL-E06 (OxPL content on apolipoprotein B-100 [apoB] detected by antibody E06), apoB-100 immune complexes (apoB-IC), OxL...

Mipomersen is a 20mer antisense oligonucleotide (ASO) that inhibits apolipoprotein B (apoB) synthesis; its low-density lipoprotein (LDL)-lowering effects should therefore result from reduced secretion of very-low-density lipoprotein (VLDL). We enrolled 17 healthy volunteers who received placebo injections weekly for 3 weeks followed by mipomersen weekly for 7 to 9 weeks. Stable isotopes were us...

Lipoprotein-associated phospholipase A₂ (Lp-PLA₂) is a risk factor of cardiovascular disease. Plasma Lp-PLA₂ is mainly associated with apolipoprotein (apo)B-containing lipoproteins, primarily with low density lipoproteins (LDLs). Importantly, only a proportion of circulating lipoproteins contain Lp-PLA₂. We determined the plasma levels of Lp-PLA₂-bound apoB (apoB/Lp-PLA₂) in patients with prima...

Over the past five years, several laboratories have used a variety of transgenic and gene-targeted mice to study apoB. These studies have helped in 1) generating new mouse models suitable for investigating the genetic and environmental factors affecting atherogenesis; 2) providing systems for investigating apoB structure/function relationships; 3) understanding the regulation of apoB gene expre...

We investigated the metabolism of very low density lipoprotein (VLDL), intermediate density lipoprotein (IDL), and low density lipoprotein (LDL) apolipoprotein B (apoB) in seven patients with combined hyperlipidemia (CHL), using 125I-labeled VLDL and 131I-labeled LDL and compartmental modeling, before and during lovastatin treatment. Lovastatin therapy significantly reduced plasma levels of LDL...

Naturally occurring mutant forms of apolipoprotein B (apoB)-100 may be able to provide valuable information on the structure-function relationships of apoB with the low density lipoprotein (LDL) receptor. ApoB-67, recently identified in a kindred displaying apoB levels 25% of normal (Welty et al. J. Clin. Invest. 1991. 87: 1748-1754), is predicted to contain 3040 amino acids and therefore, cont...

In this study, we tested the hypothesis that two separate pathways, the two-step process and an apolipoprotein B (apoB) size-dependent lipidation process, give rise to different lipoproteins. Expression of apoB-100 and C-terminally truncated forms of apoB-100 in McA-RH7777 cells demonstrated that VLDL particles can be assembled by apoB size-dependent linear lipidation, resulting in particles wh...