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Plasma Lipoproteins (plasma + lipoprotein)
Selected AbstractsAmelioration of Cadmium-Induced Oxidative Stress, Impairment in Lipids and Plasma Lipoproteins by the Combined Treatment with Quercetin and ,-Tocopherol in RatsJOURNAL OF FOOD SCIENCE, Issue 7 2010S. Milton Prabu Abstract:, Cadmium (Cd) exposure results in numerous pathological consequences including oxidative stress and dyslipidemia. The present study was designed to investigate the efficacy of combined treatment with quercetin (QE) and ,-tocopherol (AT) against Cd-induced oxidative stress and alterations in lipids and lipoproteins in the plasma and liver of rats. Oral administration of Cd (5 mg/kg bw/d) for 4 wk has shown a significant (P < 0.05) increase in thiobarbituric acid reactive substances (TBARS), lipid hydro peroxides (LOOH), total cholesterol, low density lipoprotein cholesterol (LDL-C), very low density lipoprotein cholesterol (VLDL-C), free fatty acids (FFA), phospholipids (PL), triglycerides (TGs), and the activity of hydroxyl-3-methylglutaryl-coenzyme A reductase (HMG-CoA reductase) in plasma with a significant (P > 0.05) reduction in the levels of reduced glutathione (GSH), high density lipoprotein cholesterol (HDL-C), and the activity of lecithin cholesterol acyl transferase (LCAT) in plasma. In addition, the levels of hepatic thiobarbituric acid reactive substances (TBARS), LOOH, conjugated dienes (CD), protein carbonyls (PC), and the activity of HMG-CoA reductase, levels of cholesterol, FFA, and TGs were significantly (P > 0.05) increased and the level of PL is significantly (P > 0.05) decreased along with the decreased activity of LCAT in the liver of Cd-treated rats. Oral supplementation with QE (50 mg/kg bw/d) and AT (50 mg/kg bw/d) for 4 wk in Cd intoxicated rats significantly (P > 0.05) has reduced the plasma levels of TBARS, LOOH, GSH, cholesterol, FFA, TGs, VLDL-C, LDL-C, and the activity of HMG-CoA and significantly (P > 0.05) has increased the activity of LCAT and the plasma levels of HDL-C. The oral supplementation also significantly (P > 0.05) has reduced the hepatic oxidative stress markers, cholesterol, TGs, FFA, and significantly (P > 0.05) has increased the LCAT activity and the PL in liver. Our results indicate that the combined treatment with QE and AT has normalized all the previously mentioned biochemical parameters in Cd-intoxicated rats than the individual treatments. The combined treatment has provided remarkable protection against Cd-induced oxidative stress and alterations in lipid metabolism and, thereby, reduced the Cd-mediated cardiovascular diseases. [source] Hemostatic and thrombotic markers in patients with hemoglobin E/,-thalassemia diseaseAMERICAN JOURNAL OF HEMATOLOGY, Issue 11 2007Pantep Angchaisuksiri Increased frequency of thrombosis has been observed in patients with hemoglobin E/,-thalassemia (Hb E/,-thal) disease, particularly those who have previously been splenectomized. We compared various hemostatic and thrombotic markers in blood from 15 Hb E/,-thal patients who were not splenectomized (NS), 15 who had been splenectomized (S), and 15 normal controls (NC). Levels of plasma thrombin-antithrombin, ,2 thromboglobulin, C-reactive protein, tissue plasminogen activator antigen were significantly higher in the S group than in either the NS or the NC groups, and levels of prothrombin fragment 1.2 were significantly higher in the S than in the NC group. Levels of plasminogen activator inhibitor-1 antigen were significantly higher in the S than in the NS group. Levels of protein C, protein S, antithrombin, and fibrinogen were significantly lower in the S and NS groups than in the NC group. Plasma lipoprotein(a) levels in the S and NS groups were not statistically different from NC. Our findings indicated that there is evidence of chronic low-grade coagulation and platelet activation, chronic low-grade inflammation, endothelial cell injury, impaired fibrinolysis, and decreased naturally occurring anticoagulants in splenectomized Hb E/,-thal patients. These changes may account for the increased risk of thrombosis in these patients. Am. J. Hematol., 2007. © 2007 Wiley-Liss, Inc. [source] Proteomic analysis of high-density lipoproteinPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 2 2006Farhad Rezaee Dr. Abstract Plasma lipoproteins, such as high-density lipoprotein (HDL), can serve as carriers for a wide range of proteins that are involved in processes such as lipid metabolism, thrombosis, inflammation and atherosclerosis. The identification of HDL-associated proteins is essential with regards to understanding these processes at the molecular level. In this study, a combination of proteomic approaches including 1-DE and 2-DE MALDI-TOF, isotope-coded affinity tag and Western blot analysis were employed to identify proteins associated with human HDL. To minimize potential losses of HDL-associated proteins during isolation, a one-step ultracentrifugation technique was applied and the quality of purified HDL was confirmed by nephelometry, high-performance gel chromatography, and Western blot analysis. MS analysis revealed the presence of 56 HDL-associated proteins including all known apolipoproteins and lipid transport proteins. Furthermore, proteins involved in hemostasis and thrombosis, the immune and complement system were found. In addition, growth factors, receptors, hormone-associated proteins and many other proteins were found to be associated with HDL. Our approach thus resulted in the identification of a large number of proteins associated with HDL. The combination of proteomic technologies proved to be a powerful and comprehensive tool for the identification of proteins on HDL. [source] Influence of red clover-derived isoflavones on serum lipid profile in postmenopausal womenJOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 6 2009Milan M. Terzic Abstract Aim:, Menopause is associated with adverse metabolic changes, especially in plasma lipoprotein and cholesterol levels. Estrogens have beneficial effects on lipid metabolism. Phytoestrogens are plant substances that are structurally and functionally similar to 17,-estradiol and are capable of producing estrogenic effects. The goal of the present study was to estimate the effects of red clover-derived isoflavones on serum lipid levels in postmenopausal women. Methods:, The study comprised 40 healthy postmenopausal women with an average age of 56 years. The women were divided into two groups: 22 were allocated to a red clover-derived isoflavone medication group, and 18 were allocated to a non-medication group. Total blood cholesterol, cholesterol fractions and triglycerides in the women of both groups were investigated before treatment and at 4-month intervals over the following 12 months. Results:, Both total serum cholesterol and low-density lipoprotein (LDL) cholesterol levels, as well as triglyceride levels, were decreased significantly in the group receiving phytoestrogens. However, high-density lipoprotein (HDL) cholesterol showed a significant increase. Conclusion:, Red clover phytoestrogen supplementation in postmenopausal women had favorable metabolic effects on serum lipids. Furthermore, red clover phytoestrogens have no side-effects and can be considered safe. [source] The effects of acute and chronic exercise on the vasculatureACTA PHYSIOLOGICA, Issue 4 2010J. J. Whyte Abstract Regular physical activity (endurance training, ET) has a strong positive link with cardiovascular health. The aim of this review is to draw together the current knowledge on gene expression in different cell types comprising the vessels of the circulatory system, with special emphasis on the endothelium, and how these gene products interact to influence vascular health. The effect beneficial effects of ET on the endothelium are believed to result from increased vascular shear stress during ET bouts. A number of mechanosensory mechanisms have been elucidated that may contribute to the effects of ET on vascular function, but there are questions regarding interactions among molecular pathways. For instance, increases in flow brought on by ET can reduce circulating levels of viscosity and haemostatic and inflammatory variables that may interact with increased shear stress, releasing vasoactive substances such as nitric oxide and prostacyclin, decreasing permeability to plasma lipoproteins as well as the adhesion of leucocytes. At this time the optimal rate-of-flow and rate-of-change in flow for determining whether anti-atherogenic or pro-atherogenic processes proceed remain unknown. In addition, the impact of haemodynamic variables differs with vessel size and tissue type in which arteries are located. While the hurdles to understanding the mechanism responsible for ET-induced alterations in vascular cell gene expression are significant, they in no way undermine the established benefits of regular physical activity to the cardiovascular system and to general overall health. This review summarizes current understanding of control of vascular cell gene expression by exercise and how these processes lead to improved cardiovascular health. [source] Kinetics of tryptophan oxidation in plasma lipoproteins by myeloperoxidase-generated HOClFEBS JOURNAL, Issue 13 2000Andreas Jerlich The relative susceptibility of the apoprotein components of human lipoproteins [high-density lipoprotein (HDL) and low-density lipoprotein (LDL)] and their subclasses to oxidation by the myeloperoxidase/H2O2/Cl, system in vitro was studied by measuring the decrease in rate of tryptophan fluorescence. Whereas the lipoprotein-modification rate showed a saturation type of dependence on the concentration of myeloperoxidase, a biphasic dependence on the concentration of the lipoproteins was found. High concentrations of H2O2 were also found to inhibit tryptophan oxidation in LDL but to a lesser extent in HDL. The optimal rate of LDL and HDL modification was observed at pH 6.0. HDL was modified much more rapidly than LDL, which may be due to differences in size and different relative contents of protein and lipids per particle. No differences in rates of modification of LDL subclasses were observed, when the assays were standardized to equal LDL protein concentrations, but, when standardized to equal particle mass, an optimum at subclass 8 was found, which is probably due to differences in apolipoprotein B-100 conformation. It was concluded that HDL may have a beneficial effect in retarding LDL modification in inflammatory processes. [source] pH-dependent translocation of ,-tocopherol transfer protein (,-TTP) between hepatic cytosol and late endosomesGENES TO CELLS, Issue 10 2003Masakuni Horiguchi Background:, ,-Tocopherol transfer protein (,-TTP), a member of the Sec14 protein family, plays an important role in transporting ,-tocopherol, a major lipid-soluble anti-oxidant, in the cytosolic compartment of hepatocytes and is known as a product of the causative gene for familial isolated vitamin E deficiency. It has been shown that the secretion of hepatocyte ,-tocopherol taken up with plasma lipoproteins is facilitated by ,-TTP. To explore the mechanism of ,-TTP mediated ,-tocopherol secretion, we investigated drugs which may affect this secretion. Results:, We found that, in a hepatocyte cell culture system, intracellular ,-tocopherol transport is impaired by chloroquine, an agent known for its function of elevating the pH in acidic compartments. Under chloroquine treatment, the diffuse cytosolic distribution of ,-TTP changes to a punctate pattern. Double-staining experiments with endocytosis markers revealed that ,-TTP accumulates transiently on the cytoplasmic surface of late endosomal membranes. This phenomenon is specific for hepatoma cell lines or primarily cultured hepatocytes. Other members of the Sec14 family, such as cellular retinaldehyde-binding protein (CRALBP) and supernatant protein factor (SPF), do not show this accumulation. Furthermore, we elucidate that the obligatory amino acid sequence for this function is located between amino acids 21 and 50, upstream of the N-terminal end of the lipid-binding domain. Conclusion:, We hypothesize that a liver-specific target molecule for ,-TTP exists on the late endosomal membrane surface. This transient binding may explain the mechanism of how ,-tocopherol is transferred from late endosomes to cytosolic ,-TTP. [source] Atorvastatin in dyslipidaemia of the nephrotic syndromeNEPHROLOGY, Issue 2 2003Pedro VALDIVIELSO SUMMARY: The combined dyslipidaemia that accompanies the nephrotic syndrome increases the cardiovascular risk and appears to worsen long-term renal function. Our aim was to determine the efficacy and safety of 10 mg atorvastatin in the control of dyslipidaemia in these patients. We carried out a prospective, open, 6 month study of 10 patients with primary or secondary nephrotic syndrome (proteinuria >3.5 g/day, hypoalbuminaemia, oedema and hyperlipidaemia). The changes in lipids and plasma lipoproteins were measured, as well as the safety profile (transaminases, creatine phosphokinase, fibrinogen and antithrombin III activity) and parameters of renal function. The addition of 10 mg atorvastatin daily for 6 months resulted in a 41% reduction in low density lipoprotein (LDL) cholesterol and 31% in triglycerides (both P < 0.05), and a 15% increase in high density lipoprotein (HDL) cholesterol (NS). The drug was well tolerated and there was no change in the safety profile or deterioration in renal function. In fact, the levels of proteinuria fell in all but one patient (6.2 ± 2.6 vs 4.8 ± 2.5 g/24 h; P < 0.05). Atorvastatin, at the above dose, and for the time used proved to be a safe drug that effectively reduced dyslipidaemia in patients with nephrotic syndrome. [source] Protective Effect of the Immunosuppressant Sirolimus Against Aortic Atherosclerosis In Apo E-Deficient MiceAMERICAN JOURNAL OF TRANSPLANTATION, Issue 5 2003M. Merle Elloso Atherosclerosis is a chronic inflammatory disease that develops in response to injury to the vessel wall, and is augmented by hypercholesterolemia. To further delineate the role of the immune system and local factors in this process, we assessed the effects of the immunosuppressant sirolimus (Rapamycin, RAPAMUNE®, Wyeth, Collegeville, PA) on atherosclerosis in the apoE-deficient (apoE KO) mouse, a well-accepted model of cardiovascular disease. ApoE KO mice were fed a high fat diet and sirolimus was administered. After 12 weeks, atherosclerotic lesions and plasma lipoproteins were measured. The expression of cytokines associated with atherosclerosis was also examined. All groups demonstrated plasma total cholesterol (TC) >1100 mg/dL. Sirolimus treatment was associated with a 30% increase in LDL-cholesterol (LDLc) and a dose-dependent elevation in HDL-cholesterol (HDLc). Despite increased LDLc, aortic atherosclerosis was markedly reduced in all sirolimus-treated groups. Sirolimus treatment resulted in decreased expression of IL-12p40, IFN-, and IL-10 mRNA. In contrast, TGF-,1 was elevated. Sirolimus significantly reduced atherosclerosis in apo E-KO mice; this effect is independent of, and obviates, elevated plasma TC and LDLc. Sirolimus might therefore be of benefit on atherosclerosis in patients undergoing therapy, independent of any impact on circulating lipids. [source] Seasonally changing metabolism in Atlantic salmon (Salmo salar L.) II ,, -oxidation capacity and fatty acid composition in muscle tissues and plasma lipoproteinsAQUACULTURE NUTRITION, Issue 5 2003U. Nordgarden Abstract With the aim of elucidating seasonally changing lipid metabolism in immature Atlantic salmon (Salmo salar L.) in sea water, one group was reared under simulated natural light, while one group was reared under continuous light. Fatty acid profile in plasma lipoproteins did not vary during the experiment, while , -oxidation capacity increased during spring, concurrent with decreasing temperatures. Simultaneously, the relative level of monounsaturated fatty acids (MUFA) in muscle tissue decreased (42,36%). Muscle levels of saturated fatty acids were low during early spring (19%), but then increased slowly, and muscle levels of polyunsaturated fatty acids increased during spring (from 36% to 39%). It is suggested that increased spring growth and the concomitant energy demand was met by increased lipid oxidation, where MUFA were preferred as energy substrate. [source] | ||||||||||||||||