Search results for "Lipoproteins."
showing 10 items of 492 documents
Effect of fish oil on LDL oxidation and plasma homocysteine concentrations in health.
2003
Oxidation of low-density lipoprotein (LDL) and hyperhomocysteinemia are believed to play a role in therogenesis. Whether n-3 polyunsaturated fatty acids increase LDL susceptibility to oxidation or influence homocysteine (Hcy) metabolism has long been a subject of controversy. In this study, we evaluated the effect of 8 weeks of dietary supplementation with 6 g/day of fish oil (FO; 3 g of n-3 fatty acids) on plasma lipoproteins, in vitro LDL peroxidation, antioxidant status, and plasma Hcy concentrations in 16 normolipidemic subjects. FO rapidly and significantly (P < .01) decreased plasma total and very low density lipoprotein triglyceride concentrations and had no effect on LDL or high-den…
Plasma and fibroblasts of Tangier disease patients are disturbed in transferring phospholipids onto apolipoprotein A-I
1998
Plasmas of patients with Tangier disease (TD) lack lipid-rich α-HDL which, in normal plasma, constitutes the majority of high density lipoprotein (HDL). Residual amounts of apolipoprotein (apo)A-I in TD plasma occur as lipid-poor or even lipid-free preβ-HDL. By contrast to normal plasma, TD plasma does not convert preβ-HDL into α-HDL. Moreover, fibroblasts of TD patients were found to be defective in secreting cholesterol or phospholipids in the presence of lipid-free apoA-I. We have therefore hypothesized that both defective conversion of preβ-HDL into α-HDL and defective lipid efflux from TD cells onto lipid-free apoA-I result from a disturbance in phospholipid transfer occurring in both …
Effect of continuous oestradiol-medroxyprogesterone administration on plasma lipids and lipoproteins
1991
Plasma lipids and lipoproteins were measured in 21 post-menopausal women after 4 and 8 months of continuous treatment with an orally administered combination of oestradiol and medroxyprogesterone acetate. The mean concentrations of cholesterol and low-density-lipoprotein (LDL) cholesterol were reduced by 12% (P less than 0.001) and 11% (P less than 0.01), respectively, after 4 months of treatment and by 9% (P less than 0.05) and 12% (P less than 0.05) after 8 months. The mean level of high-density-lipoprotein (HDL) cholesterol showed an initial fall of 5% (P less than 0.05) after 4 months and then increased by 13% (P less than 0.05) after 8 months of treatment. The plasma triglycerides leve…
Validating a Rapid Method for Detecting Common Polymorphisms in the APOA5 Gene by Melting Curve Analysis Using LightTyper
2005
The recently identified apolipoprotein A-V gene (APOA5) has been shown to play an important role in hypertriglyceridemia (1). Genetic variation in APOA5 has been consistently associated with plasma triglyceride concentrations in several studies (2)(3)(4). Moreover, some studies have demonstrated additional associations with lipoprotein subclasses, remnant-like particles, and cardiovascular disease risk (4)(5)(6). Several single-nucleotide polymorphisms (SNPs) in the human APOA5 gene have been detected with differing frequencies depending on the population analyzed (7)(8), and Klos et al.(7) have also suggested context-dependent associations in different populations. Overall, 5 common SNPs, …
Milder forms of atherogenic dyslipidemia in ovulatory versus anovulatory polycystic ovary syndrome phenotype
2017
BACKGROUND: Dyslipidemia is common in women with polycystic ovary syndrome (PCOS) but its prevalence in different PCOS phenotypes is still largely unknown. METHODS: We measured plasma lipids and lipoproteins in 35 anovulatory PCOS (age: 25 ± 6 years, BMI: 28 ± 6 kg/m2), 15 ovulatory PCOS (age: 30 ± 6 years, BMI: 25 ± 3 kg/m2) and 27 healthy women (controls) age- and BMI-matched with ovulatory PCOS. PCOS was diagnosed by the presence of clinical or biologic hyperandrogenism associated with chronic anovulation and/or polycystic ovaries at ultrasound. In women with normal menses chronic anovulation was indicated by low serum progesterone levels (<9.54 nmol/l) during midluteal phase (days 21…
Interleukin-18 levels are associated with low-density lipoproteins size
2009
INTRODUCTION: Both low-density lipoproteins (LDL) size and serum interleukin (IL)-18 levels have been shown to be predictors of cardiovascular morbidity and mortality. However, it is still unknown whether IL-18 levels are independently associated with LDL size. METHODS: In this cross-sectional study including 53 premenopausal women (18-45 years), LDL size (by gradient gel electrophoresis), serum IL-18, high-sensitivity C-reactive protein (hs-CRP), serum lipids, insulin sensitivity (S(I), by frequently sampled intravenous glucose tolerance test) were measured. RESULTS: LDL size correlated with IL-18 (r = -0.38, P = 0.006), hs-CRP (r = -0.40, P = 0.003), S(I) (r = 0.36, P = 0.011), serum trig…
Atherogenic lipoprotein phenotype and low-density lipoproteins size and subclasses in women with polycystic ovary syndrome.
2006
Abstract Context: An altered lipid profile is common in polycystic ovary syndrome (PCOS) and is usually characterized by increased triglycerides and low high-density lipoprotein (HDL)-cholesterol levels. In the general population, these alterations are often associated with the increase of small low-density lipoproteins (LDLs) in the so-called “atherogenic lipoprotein phenotype” (ALP) that determines a further increase of cardiovascular risk. In this study, we evaluated the presence of ALP in the plasma of women with PCOS. Setting: Measurements and analysis of LDL size were performed at the Clinic of Endocrinology, Diabetes, and Clinical Nutrition, University Hospital, Zurich. PCOS patients…
Estradiol counteracts oxidized LDL-induced asymmetric dimethylarginine production by cultured human endothelial cells.
2006
Objective: Asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide (NO) synthase, is a novel cardiovascular risk factor produced by endothelial cells. ADMA levels are mainly regulated by the activity of dimethylarginine dimethylaminohydrolases (DDAH). Endothelial release of ADMA is increased in the presence of oxidized LDL cholesterol (oxLDL), whereas estrogens stimulate NO production by endothelial cells by increasing both expression and activity of NO synthase and by reducing ADMA levels. Thus, the aim of the present study was to evaluate the estradiol effects on the DDAH/ADMA/NO pathway in cultured human umbilical vein endothelial cells (HUVEC) exposed to LDL. Methods…
Extracorporeal circuit heparinization in selective low density lipoprotein apheresis: changes in patient hemostasis and low molecular weight heparin …
1993
Treatment by low density lipoprotein (LDL) apheresis using dextran sulfate columns (DSC) leads to hemostasis alterations with prolonged activated partial thromboplastin time (APTT) of more than 120 seconds. In order to explain this hypocoagulability, we studied hemostasis parameters both in patients and in the extracorporeal circulation (ECC). Hemostasis changes are first related to unfractionated heparin (UFH)—needed to avoid circuit coagulation—which leads to high residual heparinemia in the patient (more than 3 times the recommended level for therapeutic use). Second, the hypocoagulability is induced by a coagulation factor decrease (primarily factors V, VIH, and X) mainly due to an adso…
Atherogenic forms of dyslipidaemia in women with polycystic ovary syndrome.
2009
OBJECTIVE: Dyslipidaemia is very common in patients with polycystic ovary syndrome (PCOS) but, beyond plasma lipids, atherogenic lipoprotein (Lp) and apolipoprotein (apo) alterations are still ill defined. DESIGN: We measured concentrations of apoB, Lp(a) and small, dense low-density lipoprotein (LDL) in 42 patients with PCOS [age: 28 +/- 7 years, body mass index (BMI): 27 +/- 5 kg/m(2)] vs. 37 age- and BMI-matched healthy controls. METHODS: Elevated Lp(a) levels considered were those > 30 mg/dl while elevated apoB concentrations were those > 100 g/l. RESULTS: Polycystic ovary syndrome showed increased triglycerides levels (p = 0.0011) and lower high-density lipoprotein (HDL)-cholesterol co…