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Best Practice & Research. Clinical... Jul 2023COVID-19 infections decrease total cholesterol, LDL-C, HDL-C, and apolipoprotein A-I, A-II, and B levels while triglyceride levels may be increased or inappropriately... (Review)
Review
COVID-19 infections decrease total cholesterol, LDL-C, HDL-C, and apolipoprotein A-I, A-II, and B levels while triglyceride levels may be increased or inappropriately normal for the poor nutritional status. The degree of reduction in total cholesterol, LDL-C, HDL-C, and apolipoprotein A-I are predictive of mortality. With recovery lipid/lipoprotein levels return towards pre-infection levels and studies have even suggested an increased risk of dyslipidemia post-COVID-19 infection. The potential mechanisms for these changes in lipid and lipoprotein levels are discussed. Decreased HDL-C and apolipoprotein A-I levels measured many years prior to COVID-19 infections are associated with an increased risk of severe COVID-19 infections while LDL-C, apolipoprotein B, Lp (a), and triglyceride levels were not consistently associated with an increased risk. Finally, data suggest that omega-3-fatty acids and PCSK9 inhibitors may reduce the severity of COVID-19 infections. Thus, COVID-19 infections alter lipid/lipoprotein levels and HDL-C levels may affect the risk of developing COVID-19 infections.
Topics: Humans; Proprotein Convertase 9; Triglycerides; Apolipoprotein A-I; Cholesterol, LDL; COVID-19; Lipoproteins; Cholesterol, HDL
PubMed: 36894344
DOI: 10.1016/j.beem.2023.101751 -
Trends in Endocrinology and Metabolism:... Mar 2020The tumor microenvironment (TME) is an attractive target to develop novel strategies for hormone-dependent cancers. Several molecules in the TME can favor tumor... (Review)
Review
The tumor microenvironment (TME) is an attractive target to develop novel strategies for hormone-dependent cancers. Several molecules in the TME can favor tumor development and progression, including lipoproteins. Lipoproteins are taken up by cancer cells, providing them with cholesterol and fatty acids. Cholesterol regulates cell signaling and it is converted into a series of bioactive metabolites, including hormones. The conflicting results of epidemiological and interventional studies suggest that the local availability of lipoproteins in the TME is more relevant for cancer biology than their circulating levels. Thus, reducing lipoprotein uptake and stimulating cell cholesterol efflux to high-density lipoproteins (HDLs) can represent a novel adjuvant strategy for cancer management. HDL-like particles can also act as drug delivery systems for tumor targeting.
Topics: Disease Progression; Drug Delivery Systems; Humans; Lipid Metabolism; Lipoproteins; Lipoproteins, HDL; Neoplasms, Hormone-Dependent; Tumor Microenvironment
PubMed: 31837908
DOI: 10.1016/j.tem.2019.11.005 -
Journal of Atherosclerosis and... Dec 2022In addition to the quantity and quality, the carriers, such as lipoproteins and albumin, can affect the physiological properties and clinical significance of lipids....
AIM
In addition to the quantity and quality, the carriers, such as lipoproteins and albumin, can affect the physiological properties and clinical significance of lipids. This study aimed to elucidate the modulation of the levels of ceramides and sphingosine, which are considered as proatherosclerotic lipids, in lipoproteins and lipoprotein-depleted fractions in subjects with type 2 diabetes.
METHODS
We separated the serum samples collected from healthy subjects (n=22) and subjects with type 2 diabetes (n=39) into Triglyceride (TG)-rich lipoproteins (TRL), low-density lipoprotein (LDL), high-density lipoprotein (HDL), and lipoprotein-depleted fractions via ultracentrifugation. Then, we measured the levels of six species of ceramides, sphingosine, and dihydrosphingosine via LC-MS/MS and statistically analyzed them to identify the sphingolipids in each fraction, which are associated with diabetes as well as cardiovascular and renal complications.
RESULTS
In subjects with diabetes, the levels of sphingosine and dihydrosphingosine in the TRL, LDL, and lipoprotein-depleted fractions were higher, whereas those in the HDL were lower. In addition, the ceramide levels in HDL were lower, whereas those in lipoprotein-depleted fractions were higher. Furthermore, The levels of ceramides in lipoproteins, especially LDL, were negatively associated with the presence of cardiovascular diseases and stage 4 diabetic nephropathy.
CONCLUSIONS
The contents of ceramides and sphingosine in lipoproteins and lipoprotein-depleted fractions were differently modulated in diabetes and associated with cardiovascular diseases and diabetic nephropathy. The carrier might be an important factor for the biological properties and clinical significance of these sphingolipids.
Topics: Humans; Sphingosine; Ceramides; Diabetes Mellitus, Type 2; Chromatography, Liquid; Diabetic Nephropathies; Cardiovascular Diseases; Tandem Mass Spectrometry; Lipoproteins; Triglycerides; Lipoproteins, HDL; Lipoproteins, LDL; Sphingolipids
PubMed: 35082227
DOI: 10.5551/jat.63249 -
Arteriosclerosis, Thrombosis, and... Jan 2024HDL (high-density lipoprotein), owing to its high protein content and small size, is the densest circulating lipoprotein. In contrast to lipid-laden VLDL... (Review)
Review
HDL (high-density lipoprotein), owing to its high protein content and small size, is the densest circulating lipoprotein. In contrast to lipid-laden VLDL (very-low-density lipoprotein) and LDL (low-density lipoprotein) that promote atherosclerosis, HDL is hypothesized to mitigate atherosclerosis via reverse cholesterol transport, a process that entails the uptake and clearance of excess cholesterol from peripheral tissues. This process is mediated by APOA1 (apolipoprotein A-I), the primary structural protein of HDL, as well as by the activities of additional HDL proteins. Tracer-dependent kinetic studies are an invaluable tool to study HDL-mediated reverse cholesterol transport and overall HDL metabolism in humans when a cardiovascular disease therapy is investigated. Unfortunately, HDL cholesterol-raising therapies have not been successful at reducing cardiovascular events suggesting an incomplete picture of HDL biology. However, as HDL tracer studies have evolved from radioactive isotope- to stable isotope-based strategies that in turn are reliant on mass spectrometry technologies, the complexity of the HDL proteome and its metabolism can be more readily addressed. In this review, we outline the motivations, timelines, advantages, and disadvantages of the various tracer kinetics strategies. We also feature the metabolic properties of select HDL proteins known to regulate reverse cholesterol transport, which in turn underscore that HDL lipoproteins comprise a heterogeneous particle population whose distinct protein constituents and kinetics likely determine its function and potential contribution to cholesterol clearance.
Topics: Humans; Kinetics; Lipoproteins; Lipoproteins, HDL; Cholesterol; Atherosclerosis; Biology; Cholesterol, HDL
PubMed: 38031838
DOI: 10.1161/ATVBAHA.123.319742 -
Drug Delivery Dec 2017High-density lipoprotein (HDL) and low-density lipoprotein (LDL), as human endogenous lipoprotein particles, have low toxicity, high selectivity, and good safety. They... (Review)
Review
High-density lipoprotein (HDL) and low-density lipoprotein (LDL), as human endogenous lipoprotein particles, have low toxicity, high selectivity, and good safety. They can avoid the recognition and clearance of human reticuloendothelial system. These synthetic lipoproteins (sLPs) have been attracted extensive attention as the nanovectors for tumor-targeted drug and gene delivery. Herein, recent advances in the field of anticancer based on these two lipid proteins and recombinant lipoproteins (rLPs) as target delivery vectors were analyzed and discussed.
Topics: Animals; Drug Carriers; Drug Delivery Systems; Excipients; Humans; Lipoproteins; Lipoproteins, HDL; Lipoproteins, LDL; Nanoparticles; Neoplasms
PubMed: 29069931
DOI: 10.1080/10717544.2017.1384518 -
Journal of Zhejiang University.... Jan 2009Mycoplasmas, the smallest free-living, self-replicating bacteria with diameters of 200 to 800 nm, have been reported to be associated with human diseases. It is well... (Review)
Review
Mycoplasmas, the smallest free-living, self-replicating bacteria with diameters of 200 to 800 nm, have been reported to be associated with human diseases. It is well known that the mycoplasma lipoprotein/peptide is able to modulate the host immune system, whose N-terminal structure is an important factor in inducing immunity and distinguishing Toll-like receptors (TLRs). However, there is still no clear elucidation about the pathogenic mechanism of mycoplasma lipoprotein/peptide and the signaling pathway. Some researchers have focused on understanding the structures of these proteins and the relationships between their structure and biological function. This review provides an update on the research in this field.
Topics: Lipoproteins; Models, Biological; Mycoplasma; Toll-Like Receptors
PubMed: 19198025
DOI: 10.1631/jzus.B0820256 -
Atherosclerosis Apr 2011Oxidative modifications in lipoproteins (LP), especially in low-density lipoproteins (LDL), are associated with initiation and progression of atherosclerosis. The levels... (Review)
Review
Oxidative modifications in lipoproteins (LP), especially in low-density lipoproteins (LDL), are associated with initiation and progression of atherosclerosis. The levels of a sub-fraction of LDL with oxidative characteristics, named electronegative LDL [LDL(-)], minimally oxidized LDL, and minus LDL, are known to be increased in subjects with familial hypercholesterolemia, hypertriglyceridemia, nonalcoholic steatohepatitis, diabetes mellitus, coronary artery disease, patients undergoing hemodialysis, and athletes after aerobic exercise. In addition to the oxidative profile, physical and biological characteristics of LDL(-) consist of nonenzymatic glycosylation, increased expression and activity of platelet-activating factor acetylhydrolase (PAF-AH) and phospholipase A(2) (PLA(2)), enriched NEFA content, hemoglobin and ApoB-100 cross-linking, and increase in ApoC-III and ApoE in LDL. Herein, we summarize the state of the art of the up-to-date body of knowledge on the possible origin and impact of LDL(-) in health and disease. Further, the potential perspectives of using LDL(-) as a biomarker in conditions under metabolic stress are also discussed.
Topics: 1-Alkyl-2-acetylglycerophosphocholine Esterase; Apolipoprotein B-100; Apolipoprotein C-III; Apolipoproteins E; Humans; Lipoproteins, LDL; Oxidation-Reduction
PubMed: 21292266
DOI: 10.1016/j.atherosclerosis.2010.12.028 -
Current Atherosclerosis Reports Mar 2014Advanced lipid testing has been suggested by some experts to identify patients with substantial residual risk for more aggressive targeting of lifestyle and... (Review)
Review
Advanced lipid testing has been suggested by some experts to identify patients with substantial residual risk for more aggressive targeting of lifestyle and pharmacologic therapies. It measures the subpopulation of lipoproteins and apolipoproteins, which include lipoprotein (a), apolipoprotein A-I, and apolipoprotein B, and measures of lipoprotein particle composition such as LDL particle (LPL-P) and HDL particle (HDL-P) number and size. Obesity is associated with smaller LDL-P and HDL-P sizes. Moderate weight loss via fasting/calorie restriction is associated with LDL-P size increase, whereas moderate weight loss via endurance exercise is associated with HDL-P size increase. Diets high in carbohydrates are associated with a more atherogenic advanced lipoprotein profile characterized by smaller LDL-P and HDL-P sizes. In summary, lifestyle changes such as weight loss, exercise, and dietary modification correlate with improvement in the profile of advanced lipoproteins. Regrettably, therapies targeting HDL and HDL composition have been disappointing to date.
Topics: Apolipoproteins; Cardiovascular Diseases; Exercise; Feeding Behavior; Humans; Hypolipidemic Agents; Immunoassay; Lipid Metabolism; Lipoproteins; Nuclear Magnetic Resonance, Biomolecular; Predictive Value of Tests; Prognosis; Randomized Controlled Trials as Topic; Risk Reduction Behavior
PubMed: 24445969
DOI: 10.1007/s11883-013-0394-9 -
The Medical Clinics of North America Jan 1994Lipoproteins are macromolecular complexes that transport cholesterol and triglycerides through the blood stream. The assembly and secretion of lipoproteins occurs in the... (Review)
Review
Lipoproteins are macromolecular complexes that transport cholesterol and triglycerides through the blood stream. The assembly and secretion of lipoproteins occurs in the liver and small intestine, but many modifications and transformations occur in the plasma. Plasma levels of cholesterol and triglycerides are regulated by both environmental effects on lipid metabolism and by genetic factors affecting both apoproteins on the surface of the lipoproteins and enzymes in plasma. Abnormalities of the lipoprotein transport system can increase an individual's risk for developing atherosclerosis.
Topics: Apolipoproteins; Arteriosclerosis; Humans; Lipid Metabolism; Lipoproteins
PubMed: 8283926
DOI: 10.1016/s0025-7125(16)30174-2 -
Journal of Lipid Research Oct 2022Low circulating concentrations of insulin-like growth factor binding protein-2 (IGFBP-2) have been associated with dyslipidemia, notably with high triglyceride (TG)...
Low circulating concentrations of insulin-like growth factor binding protein-2 (IGFBP-2) have been associated with dyslipidemia, notably with high triglyceride (TG) levels. However, the determinants by which IGFBP-2 influences lipoprotein metabolism, especially that of TG-rich lipoproteins (TRLs), are poorly understood. Here, we aimed to assess the relationships between IGFBP-2 levels and lipoprotein production and catabolism in human subjects. Fasting IGFBP-2 concentrations were measured in the plasma of 219 men pooled from previous lipoprotein kinetics studies. We analyzed production rate and fractional catabolic rates of TRLapoB-48, and LDL-, IDL-, and VLDLapoB-100 by multicompartmental modeling of l-[5,5,5-D3] leucine enrichment data after a 12 h primed constant infusion in individuals kept in a constant nutritional steady state. Subjects had an average BMI of 30 kg/m, plasma IGFBP-2 levels of 157 ng/ml, and TG of 2.2 mmol/l. After adjustments for age and BMI, IGFBP-2 levels were negatively associated with plasma TG (r = -0.29; P < 0.0001) and positively associated with HDL-cholesterol (r = 0.26; P < 0.0001). In addition, IGFBP-2 levels were positively associated with the fractional catabolic rate of VLDLapoB-100 (r = 0.20; P < 0.01) and IDLapoB-100 (r = 0.19; P < 0.05) and inversely with the production rate of TRLapoB-48 (r = -0.28; P < 0.001). These correlations remained statistically significant after adjustments for age, BMI, and the amount of fat given during the tracer infusion. These findings show that the association between low plasma IGFBP-2 and high TG concentrations could be due to both an impaired clearance of apoB-100-containing VLDL and IDL particles and an increased production of apoB-48-containing chylomicrons. Additional studies are necessary to investigate whether and how IGFBP-2 directly impacts the kinetics of TRL.
Topics: Humans; Male; Apolipoprotein B-100; Apolipoprotein B-48; Apolipoproteins B; Cholesterol, HDL; Chylomicrons; Insulin-Like Growth Factor Binding Protein 2; Kinetics; Leucine; Lipoproteins; Lipoproteins, VLDL; Triglycerides
PubMed: 36030928
DOI: 10.1016/j.jlr.2022.100269