Search results for "cholesterol"

Overexpression of human hepatic lipase and ApoE in transgenic rabbits attenuates response to dietary cholesterol and alters lipoprotein subclass dist…

1999

Abstract —The effect of the expression of human hepatic lipase (HL) or human apoE on plasma lipoproteins in transgenic rabbits in response to dietary cholesterol was compared with the response of nontransgenic control rabbits. Supplementation of a chow diet with 0.3% cholesterol and 3.0% soybean oil for 10 weeks resulted in markedly increased levels of plasma cholesterol and VLDL and IDL in control rabbits as expected. Expression of either HL or apoE reduced plasma cholesterol response by 75% and 60%, respectively. The HL transgenic rabbits had substantial reductions in medium and small VLDL and IDL fractions but not in larger VLDL. LDL levels were also reduced, with a shift from larger, m…

Increased Atherosclerotic Lesions in ApoE Mice With Plasma Phospholipid Transfer Protein Overexpression

2003

Objective— Plasma phospholipid transfer protein (PLTP) is involved in the metabolism of HDL and apolipoprotein B (apoB)-containing lipoproteins. Atherosclerosis susceptibility is decreased in mice with PLTP deficiency that is associated with decreased liver production of apoB-containing lipoproteins and increase in their antioxidant. To investigate additionally the effect of PLTP on the development of atherosclerosis, we overexpressed PLTP in mice. Methods and Results— PLTP was overexpressed in apoE knockout mice using an adenovirus-associated virus (AAV)-mediated system. Plasma PLTP activity was 1.3- to 2-fold higher in mice injected with AAV-PLTP than in mice injected with control AAV-GF…

Lipid and Apoprotein Profile in Renal Transplant Recipients

1991

Lipid and apoprotein profiles of renal transplant recipients were compared with that of a group of uremic patients on hemodialytic treatment. Total cholesterol, HDL-cholesterol, apo AI and apo B were higher and triglycerides, apo CII, apo CIII and apo E lower in renal transplant patients. Type IIa and IIb were the prevalent phenotypes in renal transplant recipients.

Effect of rat plasma high density lipoprotein with or without apolipoprotein E on the cholesterol uptake and on the induction of the corticosteroid b…

1991

Abstract High density lipoprotein (HDL) has been shown to induce the cellular accumulation of cholesterol esters and the biosynthesis of 21-hydroxysteroids (corticosteroids) newborn rat adrenocortical cells cultivated in serum-free medium. In order to identify the component(s) of HDL responsible for these effects, we investigated the ability of rat HDL subfractions and HDL with or without apolipoprotein E to deliver cholesterol to cells and to stimulate the steroid biosynthetic pathways in adrenal cultured cells. The total cholesterol uptake from HDL 2 was greater than that observed with HDL rich in apolipoprotein E (HDL 1 and HDL c ). Furthermore, the increase of the ratio between 21-hydro…

Knock-down of the oxysterol receptor LXRα impairs cholesterol efflux in human primary macrophages: lack of compensation by LXRβ activation.

2012

Liver X Receptors (LXRs) α and β are oxysterol-activated nuclear receptors involved in the control of lipid metabolism and inflammation. Pharmacological activation of LXR is promising in the treatment of atherosclerosis since it can promote cholesterol efflux from macrophages and prevent foam cell formation. However, the development of LXR agonists has been limited by undesirable side-effects such as hepatic steatosis mediated by LXRα activation. Therefore, it has been proposed that targeting LXRα activators to extrahepatic tissues or using LXRβ-specific activators could be used as alternative strategies. It is not clear whether these molecules will retain the full atheroprotective potentia…

Gene-diet interaction in plasma lipid response to plant sterols and stanols: A review of clinical trials

2021

Abstract Plant sterols and stanols (PS) are well known for their cholesterol-lowering effect by reducing intestinal absorption of cholesterol. However, genetic factors modulate the low-density lipoprotein cholesterol (LDL-C) response to PS therapy. This review examines clinical trials evaluating the impact of the main genes associated with response of plasma lipid concentrations to PS intake: APOE, CYP7A1, ABCG5/G8, NPC1L1, CETP, APOA4/A5, SCARBI, HMGCR, PPARα, LIPC, MTHFR and LPA. Evidence indicates that carriers of mutant allele of the CYP7A1 c. −204 A > C variant experience a greater plasma cholesterol reduction after PS intake, although there is discrepancy for the rest of genetic varia…

Cholesterol in Alzheimer’s Disease and other Amyloidogenic Disorders

2010

The complex association of cholesterol metabolism and Alzheimer’s disease is presented in depth, including the possible benefits to be gained from cholesterol-lowering statin therapy. Then follows a survey of the role of neuronal membrane cholesterol in Aβ pore formation and Aβ fibrillogenesis, together with the link with membrane raft domains and gangliosides. The contribution of structural studies to Aβ fibrillogenesis, using TEM and AFM, is given some emphasis. The role of apolipoprotein E and its isoforms, in particular ApoE4, in cholesterol and Aβ binding is presented, in relation to genetic risk factors for Alzheimer’s disease. Increasing evidence suggests that cholesterol oxidation p…

Reduced VLDL clearance in ApoeNpc1 mice is associated with increased Pcsk9 and Idol expression and decreased hepatic LDL-receptor levels

2010

Niemann-Pick type C1 (NPC1) promotes the transport of LDL receptor (LDL-R)-derived cholesterol from late endosomes/lysosomes to other cellular compartments. NPC1-deficient cells showed impaired regulation of liver_X receptor (LXR) and sterol regulatory element-binding protein (SREBP) target genes. We observed that Apoe(-/-)Npc1(-/-) mice displayed a marked increase in total plasma cholesterol mainly due to increased VLDL, reflecting decreased clearance. Although nuclear SREBP-2 and Ldlr mRNA levels were increased in Apoe(-/-)Npc1(-/-) liver, LDL-R protein levels were decreased in association with marked induction of proprotein convertase subtilisin/kexin type 9 (Pcsk9) and inducible degrade…

Effect of an aqueous extract of Ajuga iva on glycaemia, reverse cholesterol transport and atherogenic ratios in rats with streptozotocin-induced diab…

2008

Lateral organization of G M1 in phase-separated monolayers visualized by scanning force microscopy

2002

Phase separation of glycolipids in lipid mono- and bilayers is of great interest for the understanding of membrane function. The distribution of the ganglioside GM1 in sphingomyelin (SM)/1-palmitoyl-2-oleoyl- sn-glycero-3-phosphocholine (POPC), SM/1,2-dipalmitoyl- sn-glycero-3-phosphocholine (DOPC) and SM/cholesterol/POPC Langmuir-Blodgett (LB) monolayers transferred at 36 mN/m has been studied by scanning force microscopy. Besides lateral organization of the glycolipid in LB monolayers as deduced from topography, material properties have been investigated by phase imaging, pulsed force mode and force modulation microscopy. It was shown that GM1 preferentially clusters in an ordered lipid m…