An autosomal recessively inherited disorder characterized by the accumulation of intermediate-density lipoprotein (IDL or broad-beta-lipoprotein). IDL has a CHOLESTEROL to TRIGLYCERIDES ratio greater than that of VERY-LOW-DENSITY LIPOPROTEINS. This disorder is due to mutation of APOLIPOPROTEINS E, a receptor-binding component of VLDL and CHYLOMICRONS, resulting in their reduced clearance and high plasma levels of both cholesterol and triglycerides.
A severe type of hyperlipidemia, sometimes familial, that is characterized by the elevation of both plasma CHYLOMICRONS and TRIGLYCERIDES contained in VERY-LOW-DENSITY LIPOPROTEINS. Type V hyperlipoproteinemia is often associated with DIABETES MELLITUS and is not caused by reduced LIPOPROTEIN LIPASE activity as in HYPERLIPOPROTEINEMIA TYPE I .
An inherited condition due to a deficiency of either LIPOPROTEIN LIPASE or APOLIPOPROTEIN C-II (a lipase-activating protein). The lack of lipase activities results in inability to remove CHYLOMICRONS and TRIGLYCERIDES from the blood which has a creamy top layer after standing.
A hypertriglyceridemia disorder, often with autosomal dominant inheritance. It is characterized by the persistent elevations of plasma TRIGLYCERIDES, endogenously synthesized and contained predominantly in VERY-LOW-DENSITY LIPOPROTEINS (pre-beta lipoproteins). In contrast, the plasma CHOLESTEROL and PHOSPHOLIPIDS usually remain within normal limits.
Conditions with abnormally elevated levels of LIPOPROTEINS in the blood. They may be inherited, acquired, primary, or secondary. Hyperlipoproteinemias are classified according to the pattern of lipoproteins on electrophoresis or ultracentrifugation.
'Blood Protein Disorders' refer to conditions characterized by an abnormal amount, structure, or function of proteins present in the blood, including immunoglobulins, coagulation factors, complement components, and transport proteins, which can lead to various clinical manifestations such as immune dysfunction, bleeding disorders, or metabolic imbalances.
A group of familial disorders characterized by elevated circulating cholesterol contained in either LOW-DENSITY LIPOPROTEINS alone or also in VERY-LOW-DENSITY LIPOPROTEINS (pre-beta lipoproteins).
One of three major isoforms of apolipoprotein E. In humans, Apo E2 differs from APOLIPOPROTEIN E3 at one residue 158 where arginine is replaced by cysteine (R158--C). In contrast to Apo E3, Apo E2 displays extremely low binding affinity for LDL receptors (RECEPTORS, LDL) which mediate the internalization and catabolism of lipoprotein particles in liver cells. ApoE2 allelic homozygosity is associated with HYPERLIPOPROTEINEMIA TYPE III.
A class of lipoproteins of very light (0.93-1.006 g/ml) large size (30-80 nm) particles with a core composed mainly of TRIGLYCERIDES and a surface monolayer of PHOSPHOLIPIDS and CHOLESTEROL into which are imbedded the apolipoproteins B, E, and C. VLDL facilitates the transport of endogenously made triglycerides to extrahepatic tissues. As triglycerides and Apo C are removed, VLDL is converted to INTERMEDIATE-DENSITY LIPOPROTEINS, then to LOW-DENSITY LIPOPROTEINS from which cholesterol is delivered to the extrahepatic tissues.
Conditions with excess LIPIDS in the blood.
A condition marked by the development of widespread xanthomas, yellow tumor-like structures filled with lipid deposits. Xanthomas can be found in a variety of tissues including the SKIN; TENDONS; joints of KNEES and ELBOWS. Xanthomatosis is associated with disturbance of LIPID METABOLISM and formation of FOAM CELLS.
A class of protein components which can be found in several lipoproteins including HIGH-DENSITY LIPOPROTEINS; VERY-LOW-DENSITY LIPOPROTEINS; and CHYLOMICRONS. Synthesized in most organs, Apo E is important in the global transport of lipids and cholesterol throughout the body. Apo E is also a ligand for LDL receptors (RECEPTORS, LDL) that mediates the binding, internalization, and catabolism of lipoprotein particles in cells. There are several allelic isoforms (such as E2, E3, and E4). Deficiency or defects in Apo E are causes of HYPERLIPOPROTEINEMIA TYPE III.
Triglycerides are the most common type of fat in the body, stored in fat cells and used as energy; they are measured in blood tests to assess heart disease risk, with high levels often resulting from dietary habits, obesity, physical inactivity, smoking, and alcohol consumption.
Lipid-protein complexes involved in the transportation and metabolism of lipids in the body. They are spherical particles consisting of a hydrophobic core of TRIGLYCERIDES and CHOLESTEROL ESTERS surrounded by a layer of hydrophilic free CHOLESTEROL; PHOSPHOLIPIDS; and APOLIPOPROTEINS. Lipoproteins are classified by their varying buoyant density and sizes.
A 34-kDa glycosylated protein. A major and most common isoform of apolipoprotein E. Therefore, it is also known as apolipoprotein E (ApoE). In human, Apo E3 is a 299-amino acid protein with a cysteine at the 112 and an arginine at the 158 position. It is involved with the transport of TRIGLYCERIDES; PHOSPHOLIPIDS; CHOLESTEROL; and CHOLESTERYL ESTERS in and out of the cells.
A type of familial lipid metabolism disorder characterized by a variable pattern of elevated plasma CHOLESTEROL and/or TRIGLYCERIDES. Multiple genes on different chromosomes may be involved, such as the major late transcription factor (UPSTREAM STIMULATORY FACTORS) on CHROMOSOME 1.
The principal sterol of all higher animals, distributed in body tissues, especially the brain and spinal cord, and in animal fats and oils.
An enzyme of the hydrolase class that catalyzes the reaction of triacylglycerol and water to yield diacylglycerol and a fatty acid anion. The enzyme hydrolyzes triacylglycerols in chylomicrons, very-low-density lipoproteins, low-density lipoproteins, and diacylglycerols. It occurs on capillary endothelial surfaces, especially in mammary, muscle, and adipose tissue. Genetic deficiency of the enzyme causes familial hyperlipoproteinemia Type I. (Dorland, 27th ed) EC 3.1.1.34.
Protein components on the surface of LIPOPROTEINS. They form a layer surrounding the hydrophobic lipid core. There are several classes of apolipoproteins with each playing a different role in lipid transport and LIPID METABOLISM. These proteins are synthesized mainly in the LIVER and the INTESTINES.
A class of lipoproteins of small size (18-25 nm) and light (1.019-1.063 g/ml) particles with a core composed mainly of CHOLESTEROL ESTERS and smaller amounts of TRIGLYCERIDES. The surface monolayer consists mostly of PHOSPHOLIPIDS, a single copy of APOLIPOPROTEIN B-100, and free cholesterol molecules. The main LDL function is to transport cholesterol and cholesterol esters to extrahepatic tissues.
A class of lipoproteins that carry dietary CHOLESTEROL and TRIGLYCERIDES from the SMALL INTESTINE to the tissues. Their density (0.93-1.006 g/ml) is the same as that of VERY-LOW-DENSITY LIPOPROTEINS.
A group of apolipoproteins that can readily exchange among the various classes of lipoproteins (HDL; VLDL; CHYLOMICRONS). After lipolysis of TRIGLYCERIDES on VLDL and chylomicrons, Apo-C proteins are normally transferred to HDL. The subtypes can modulate remnant binding to receptors, LECITHIN CHOLESTEROL ACYLTRANSFERASE, or LIPOPROTEIN LIPASE.
Electrophoresis applied to BLOOD PROTEINS.
Cholesterol which is contained in or bound to very low density lipoproteins (VLDL). High circulating levels of VLDL cholesterol are found in HYPERLIPOPROTEINEMIA TYPE IIB. The cholesterol on the VLDL is eventually delivered by LOW-DENSITY LIPOPROTEINS to the tissues after the catabolism of VLDL to INTERMEDIATE-DENSITY LIPOPROTEINS, then to LDL.
A fibrillar collagen consisting of three identical alpha1(III) chains that is widely distributed in many tissues containing COLLAGEN TYPE I. It is particularly abundant in BLOOD VESSELS and may play a role in tissues with elastic characteristics.
Receptors on the plasma membrane of nonhepatic cells that specifically bind LDL. The receptors are localized in specialized regions called coated pits. Hypercholesteremia is caused by an allelic genetic defect of three types: 1, receptors do not bind to LDL; 2, there is reduced binding of LDL; and 3, there is normal binding but no internalization of LDL. In consequence, entry of cholesterol esters into the cell is impaired and the intracellular feedback by cholesterol on 3-hydroxy-3-methylglutaryl CoA reductase is lacking.
Electrophoresis in which paper is used as the diffusion medium. This technique is confined almost entirely to separations of small molecules such as amino acids, peptides, and nucleotides, and relatively high voltages are nearly always used.
A 9-kDa protein component of VERY-LOW-DENSITY LIPOPROTEINS. It contains a cofactor for LIPOPROTEIN LIPASE and activates several triacylglycerol lipases. The association of Apo C-II with plasma CHYLOMICRONS; VLDL, and HIGH-DENSITY LIPOPROTEINS is reversible and changes rapidly as a function of triglyceride metabolism. Clinically, Apo C-II deficiency is similar to lipoprotein lipase deficiency (HYPERLIPOPROTEINEMIA TYPE I) and is therefore called hyperlipoproteinemia type IB.
A lipid-regulating agent that lowers elevated serum lipids primarily by decreasing serum triglycerides with a variable reduction in total cholesterol.
A condition of elevated levels of TRIGLYCERIDES in the blood.
A bile acid, usually conjugated with either glycine or taurine. It acts as a detergent to solubilize fats for intestinal absorption and is reabsorbed by the small intestine. It is used as cholagogue, a choleretic laxative, and to prevent or dissolve gallstones.
The 3 alpha,7 alpha,12 alpha-trihydroxy-5 beta-cholanic acid family of bile acids in man, usually conjugated with glycine or taurine. They act as detergents to solubilize fats for intestinal absorption, are reabsorbed by the small intestine, and are used as cholagogues and choleretics.
Centrifugation with a centrifuge that develops centrifugal fields of more than 100,000 times gravity. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
A class of lipoproteins of small size (4-13 nm) and dense (greater than 1.063 g/ml) particles. HDL lipoproteins, synthesized in the liver without a lipid core, accumulate cholesterol esters from peripheral tissues and transport them to the liver for re-utilization or elimination from the body (the reverse cholesterol transport). Their major protein component is APOLIPOPROTEIN A-I. HDL also shuttle APOLIPOPROTEINS C and APOLIPOPROTEINS E to and from triglyceride-rich lipoproteins during their catabolism. HDL plasma level has been inversely correlated with the risk of cardiovascular diseases.
A highly acidic mucopolysaccharide formed of equal parts of sulfated D-glucosamine and D-glucuronic acid with sulfaminic bridges. The molecular weight ranges from six to twenty thousand. Heparin occurs in and is obtained from liver, lung, mast cells, etc., of vertebrates. Its function is unknown, but it is used to prevent blood clotting in vivo and vitro, in the form of many different salts.
A 9-kDa protein component of VERY-LOW-DENSITY LIPOPROTEINS and CHYLOMICRON REMNANTS. Apo C-III, synthesized in the liver, is an inhibitor of LIPOPROTEIN LIPASE. Apo C-III modulates the binding of chylomicron remnants and VLDL to receptors (RECEPTORS, LDL) thus decreases the uptake of triglyceride-rich particles by the liver cells and subsequent degradation. The normal Apo C-III is glycosylated. There are several polymorphic forms with varying amounts of SIALIC ACID (Apo C-III-0, Apo C-III-1, and Apo C-III-2).
A generic term for fats and lipoids, the alcohol-ether-soluble constituents of protoplasm, which are insoluble in water. They comprise the fats, fatty oils, essential oils, waxes, phospholipids, glycolipids, sulfolipids, aminolipids, chromolipids (lipochromes), and fatty acids. (Grant & Hackh's Chemical Dictionary, 5th ed)
Electrophoresis in which agar or agarose gel is used as the diffusion medium.
An enzyme of the hydrolase class that catalyzes the reaction of triacylglycerol and water to yield diacylglycerol and a fatty acid anion. It is produced by glands on the tongue and by the pancreas and initiates the digestion of dietary fats. (From Dorland, 27th ed) EC 3.1.1.3.
Cholesterol present in food, especially in animal products.
Electrophoresis in which a pH gradient is established in a gel medium and proteins migrate until they reach the site (or focus) at which the pH is equal to their isoelectric point.
The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.
An individual in which both alleles at a given locus are identical.
The record of descent or ancestry, particularly of a particular condition or trait, indicating individual family members, their relationships, and their status with respect to the trait or condition.
Major structural proteins of triacylglycerol-rich LIPOPROTEINS. There are two forms, apolipoprotein B-100 and apolipoprotein B-48, both derived from a single gene. ApoB-100 expressed in the liver is found in low-density lipoproteins (LIPOPROTEINS, LDL; LIPOPROTEINS, VLDL). ApoB-48 expressed in the intestine is found in CHYLOMICRONS. They are important in the biosynthesis, transport, and metabolism of triacylglycerol-rich lipoproteins. Plasma Apo-B levels are high in atherosclerotic patients but non-detectable in ABETALIPOPROTEINEMIA.
An electrochemical process in which macromolecules or colloidal particles with a net electric charge migrate in a solution under the influence of an electric current.
The protein components of a number of complexes, such as enzymes (APOENZYMES), ferritin (APOFERRITINS), or lipoproteins (APOLIPOPROTEINS).
A condition with abnormally high levels of CHOLESTEROL in the blood. It is defined as a cholesterol value exceeding the 95th percentile for the population.
Thickening and loss of elasticity of the walls of ARTERIES of all sizes. There are many forms classified by the types of lesions and arteries involved, such as ATHEROSCLEROSIS with fatty lesions in the ARTERIAL INTIMA of medium and large muscular arteries.
Structural proteins of the alpha-lipoproteins (HIGH DENSITY LIPOPROTEINS), including APOLIPOPROTEIN A-I and APOLIPOPROTEIN A-II. They can modulate the activity of LECITHIN CHOLESTEROL ACYLTRANSFERASE. These apolipoproteins are low in atherosclerotic patients. They are either absent or present in extremely low plasma concentration in TANGIER DISEASE.

Characterization of remnant-like particles isolated by immunoaffinity gel from the plasma of type III and type IV hyperlipoproteinemic patients. (1/114)

Previous studies have investigated the potential atherogenicity and thrombogenicity of triglyceride-rich lipoprotein (TRL) remnants by isolating them from plasma within a remnant-like particle (RLP) fraction, using an immunoaffinity gel containing specific anti-apoB-100 and anti-apoA-I antibodies. In order to characterize lipoproteins in this RLP fraction and to determine to what extent their composition varies from one individual to another, we have used automated gel filtration chromatography to determine the size heterogeneity of RLP isolated from normolipidemic control subjects (n = 8), and from type III (n = 6) and type IV (n = 9) hyperlipoproteinemic patients, who by selection had similarly elevated levels of plasma triglyceride (406 +/- 43 and 397 +/- 35 mg/dl, respectively). Plasma RLP triglyceride, cholesterol, apoB, apoC-III, and apoE concentrations were elevated 2- to 6-fold (P < 0. 05) in hyperlipoproteinemic patients compared to controls. RLP fractions of type III patients were enriched in cholesterol and apoE compared to those of type IV patients, and RLP of type IV patients were enriched in triglyceride and apoC-III relative to those of normolipidemic subjects. In normolipidemic subjects, the majority of RLP had a size similar to LDL or HDL. The RLP of hyperlipoproteinemic patients were, however, larger and were similar in size to TRL, or were intermediate in size (i.e., ISL) between that of TRL and LDL. Compared to controls, ISL in the RLP fraction of type III patients were enriched in apoE relative to apoC-III, whereas in type IV patients they were enriched in apoC-III relative to apoE. These results demonstrate that: 1) RLP are heterogeneous in size and composition in both normolipidemic and hypertriglyceridemic subjects, and 2) the apoE and apoC-III composition of RLP is different in type III compared to type IV hyperlipoproteinemic patients.  (+info)

Modification of type III VLDL, their remnants, and VLDL from ApoE-knockout mice by p-hydroxyphenylacetaldehyde, a product of myeloperoxidase activity, causes marked cholesteryl ester accumulation in macrophages. (2/114)

Very low density lipoproteins (VLDLs) from apolipoprotein (apo) E2/E2 subjects with type III hyperlipoproteinemia, VLDL remnants, and VLDL from apoE-knockout (EKO) mice are taken up poorly by macrophages. The present study examined whether VLDL modification by the reactive aldehyde p-hydroxyphenylacetaldehyde (pHA) enhances cholesteryl ester (CE) accumulation by J774A.1 macrophages. pHA is the major product derived from the oxidation of L-tyrosine by myeloperoxidase and is a component of human atherosclerotic lesions. Incubation of J774A.1 cells with native type III VLDL, their remnants, and EKO-VLDL increased cellular CE by only 3-, 5-, and 5-fold, respectively, compared with controls. In striking contrast, cells exposed to VLDL modified by purified pHA (pHA-VLDL) exhibited marked increases in cellular CE of 38-, 47-, and 35-fold, respectively (P95%, CE accumulation induced by copper-oxidized VLDL. These results demonstrate a novel mechanism for the conversion of type III VLDLs, their remnants, and EKO-VLDL into atherogenic particles and suggest that macrophage uptake of pHA-VLDL (1) requires catalytically active lipoprotein lipase, (2) involves acyl coenzyme A:cholesterol acyltransferase-mediated cholesterol esterification, and (3) involves pathways distinct from the SR-A.  (+info)

Ratio of remnant-like particle-cholesterol to serum total triglycerides is an effective alternative to ultracentrifugal and electrophoretic methods in the diagnosis of familial type III hyperlipoproteinemia. (3/114)

BACKGROUND: Familial type III hyperlipoproteinemia (HLP) is characterized by the presence of beta-migrating VLDL (beta-VLDL) and increased risk of cardiovascular disease. Assessment of plasma beta-VLDL is achieved by measuring the ratio of VLDL-cholesterol (VLDL-C) to total plasma triglycerides (TGs) or by detecting beta-VLDL in total VLDL. The objective of this study was to compare the clinical utility of the ratio of remnant-like particle-cholesterol (RLP-C) to total TGs with that of the current methods for diagnosing type III HLP. METHODS: Detection of beta-VLDL by electrophoresis of VLDL was used to define type III HLP. Twenty-eight patients with type III HLP and 43 subjects lacking beta-VLDL were investigated. Fasting TG concentrations were >2.26 mmol/L in all subjects. Subjects were separated into three groups: group 1, serum total cholesterol 5.18 mmol/L and TGs between 2.26 and 9.04 mmol/L (n = 51); and group 3, TGs >9.04 mmol/L (n = 9). RESULTS: In group 2, a RLP-C-to-total TG molar ratio >/=0.23 (>/=0.10 when using mg/dL) and a VLDL-C-to-total TG molar ratio >/=0.69 (>/=0.30 when using mg/dL) correctly classified 94% and 90% of the subjects, respectively. The utility of the RLP-C-to-total TG ratio in diagnosing type III HLP decreased in patients in the other two groups. CONCLUSION: When used in an appropriate target population, the RLP-C-to-total TG ratio is a convenient and effective alternative to ultracentrifugal and electrophoretic methods for diagnosing type III HLP.  (+info)

Pathogenesis of type III hyperlipoproteinemia (dysbetalipoproteinemia). Questions, quandaries, and paradoxes. (4/114)

Type III hyperlipoproteinemia (HLP) is a genetic disorder characterized by accumulation of remnant lipoproteins in the plasma and development of premature atherosclerosis. Although receptor binding-defective forms of apolipoprotein (apo) E are the common denominator in this disorder, a number of apparent paradoxes concerning its pathogenesis still exist. However, studies in transgenic animals are resolving the mechanisms underlying this disorder. PARADOX I: Defective apoE (commonly apoE2) is essential but not sufficient to cause overt type III HLP. In fact, most apoE2 homozygotes are hypolipidemic. Studies in apoE2 transgenic models have demonstrated the impact of other genes or hormones in converting the hypolipidemia to hyperlipidemia. PARADOX II: Among apoE2 homozygotes, men are more susceptible than women to type III HLP. Transgenic studies have shown that estrogen affects both LDL receptor expression and lipolytic processing, explaining the resistance of women to this disorder until after menopause. PARADOX III: ApoE deficiency is associated with hypercholesterolemia, whereas the type III HLP phenotype is characterized by both hypercholesterolemia and hypertriglyceridemia. The hypercholesterolemia is caused by impaired receptor-mediated clearance, whereas the hypertriglyceridemia is caused primarily by impaired lipolytic processing of remnants and increased VLDL production associated with increased levels of apoE. PARADOX IV: ApoE2 is associated with recessive inheritance of this disorder, whereas other defective apoE variants are associated with dominant inheritance. Determinants of the mode of inheritance are the differential binding of apoE variants to the LDL receptor versus the HSPG/LRP complex and the preference of certain apoE variants for specific lipoproteins. Thus, the pathogenesis of this sometimes mysterious disorder has been clarified.  (+info)

Apolipoprotein E2 (Lys146-->Gln) causes hypertriglyceridemia due to an apolipoprotein E variant-specific inhibition of lipolysis of very low density lipoproteins-triglycerides. (5/114)

The apolipoprotein E2 (Lys146-->Gln) variant is associated with a dominant form of familial dysbetalipoproteinemia. Heterozygous carriers of this variant have elevated levels of plasma triglycerides, cholesterol, and apolipoprotein E (apoE). It was hypothesized that the high amounts of triglycerides in the very low density lipoprotein (VLDL) fraction are due to a disturbed lipolysis of VLDL. To test this hypothesis, apoE knockout mice were injected with an adenovirus containing the human APOE*2 (Lys146-->Gln) gene, Ad-E2(146), under the control of the cytomegalovirus promoter. ApoE knockout mice injected with an adenovirus vector encoding human apoE3 (Ad-E3) were used as controls. Five days after adenovirus injection, plasma cholesterol levels of mice injected with a high dose of Ad-E2(146) (2x10(9) plaque-forming units) were not changed compared with preinjection levels, whereas in the group who received a low dose of Ad-E2(146) (5x10(8) plaque-forming units) and in the groups injected with a low or a high dose of Ad-E3, plasma cholesterol levels were decreased 5-, 6-, and 12-fold, respectively. Plasma triglycerides were not affected in mice injected with Ad-E3. In contrast, a 7-fold increase in plasma triglycerides was observed in mice injected with the low dose of Ad-E2(146) compared with mice injected with Ad-E3. Injection with the high dose of Ad-E2(146) resulted in a dramatic increase of plasma triglycerides (50-fold compared with Ad-E3 injection). In vitro lipolysis experiments showed that the lipolysis rate of VLDLs containing normal amounts of apoE2 (Lys146-->Gln) was decreased by 54% compared with that of VLDLs containing comparable amounts of apoE3. The in vivo VLDL-triglyceride production rate of Ad-E2(146)-injected mice was not significantly different from that of Ad-E3-injected mice. These results demonstrate that expression of apoE2 (Lys146-->Gln) causes hypertriglyceridemia due to an apoE variant-specific inhibition of the hydrolysis of VLDL-triglycerides.  (+info)

Analytical and clinical evaluation of two homogeneous assays for LDL-cholesterol in hyperlipidemic patients. (6/114)

BACKGROUND: LDL-cholesterol (LDL-C) concentrations are the primary basis for treatment guidelines established for hyperlipidemic patients. LDL-C concentrations are commonly monitored by means of the Friedewald formula, which provides a relative estimation of LDL-C concentration when the triglyceride concentration is <2000 mg/L and there are no abnormal lipids. The Friedewald formula has several limitations and may not meet the current total error requirement of <12% in LDL-C measurements. METHODS: We evaluated the analytical and clinical performance of two direct methods (Roche and Wako) by analyzing 313 fresh serum samples obtained from dyslipidemic patients in a lipid clinic and comparing them with modified beta-quantification. RESULTS: Both homogeneous assays displayed excellent precision (CV <2%). The Roche method showed a mean total error of 7.72%, and the Wako method showed a mean total error of 4.46% over a wide range of LDL-C concentrations. The Roche method correlated highly with the modified beta-quantification assay (r = 0.929; y = 1.052x - 168 mg/L; n = 166) and showed a bias of -4. 5% as a result of the assigned standard value. The Wako method also correlated highly with beta-quantification (r = 0.966; y = 0.9125x + 104.8 mg/L; n = 145) without significant bias. The Roche method correctly classified 97% of patients with triglycerides <2000 mg/L, 75% of patients with type IIb hyperlipemia (HPL), and 84% of patients with type IV HPL based on the cutpoints of 1300 and 1600 mg/L, compared with 98%, 78.4%, and 89%, respectively, for the Wako method. In dysbetalipoproteinemic patients, both methods have a 30% mean positive bias compared with beta-quantification. CONCLUSIONS: Both direct methods can be a useful alternative when ultracentrifugation is not available for the diagnosis and control of lipid-lowering medication for patients with mixed HPL, but not for patients with type III hyperlipidemia.  (+info)

Variable expression of hypercholesterolemia in Apolipoprotein E2* (Arg136 --> Cys) heterozygotes. (7/114)

In the process of population screening for apo E gene polymorphism with the PCR and subsequent restriction analysis, we identified a female who demonstrated heterozygosity for an unusual restriction fragment caused by the loss of a CfoI restriction site. Sequence analysis of the apo E gene was performed and a carrier of the mutant allele with C --> T substitution at cDNA position 3817 was identified, which caused an Arg136 --> Cys change. The first-line relatives have been screened for this rare mutation with PCR and restriction analysis of PCR products. The complete lipoprotein parameters have been determined in the probands family. In the family, only one child had the same mutant allele as his mother had. The proband (7.49 mmol/l) with her siblings had hypercholesterolemia and a high body mass index (BMI 31.6 kg/m2). By contrast, her son had a normal lipid spectrum with normal BMI. We described the mutation apo E2* (Arg136 --> Cys) in a family with elevated lipid levels, but there was no confirmation of the connection between this mutation and type III hyperlipoproteinemia or hyperlipoproteinemia at all. In the case of this mutation, other factors (mainly genetic) are important for the development of lipid metabolism disorders.  (+info)

Protease inhibitor related type III hyperlipoproteinaemia is common and not associated with apolipoprotein-E E2/E2 phenotype. (8/114)

OBJECTIVE: To determine the prevalence of type III hyperlipoproteinaemia in a cohort of HIV infected patients taking protease inhibitors and its correlation with the apolipoprotein-E2 isoform. DESIGN: Cross sectional study of 57 consecutive HIV infected subjects taking protease inhibitor therapy for a median of 12.5 (1-29) months, seen in an outpatient HIV clinic. Controls were 17 patients on non-nucleoside reverse transcriptor inhibitor therapy (NNRTI) for 9 (1-19) months and 50 antiviral naive patients. METHODS: Fasting cholesterol, triglyceride, HDL cholesterol, lipoprotein (a), and glucose were measured. Lipoprotein electrophoresis was performed on patients with a cholesterol >6.5 mmol/l and a triglyceride concentration of >4.5 mmol/l. Apolipoprotein-E phenotype was determined in serum. RESULTS: Dyslipidaemia was found in 43 (75%) PI treated patients-37 with triglyceride >2.3 mmol/l, 30 with cholesterol >6.5 mmol/l, and nine with HDL cholesterol <0.9 mmol/l. 38% had a lipoprotein (a) >300 mg/l. 11 patients (19.3%) had a type III hyperlipoproteinaemia pattern. Only one was homozygous for the E2 phenotype and none had clinical diabetes. An additional patient had a serum lipid profile compatible with type III hyperlipoproteinaemia and an E3/E2 phenotype in whom electrophoresis was not carried out before treatment. Six (35%) of the NNRTI and 16 (32%) of the antiviral naive patients had dyslipidaemia. 18 (31.6%) of the PI and none of the control patients had a cholesterol and/or triglyceride >8 mmol/l. CONCLUSION: Type III hyperlipoproteinaemia is common in this group of patients and need not be associated with the apolipoprotein-E2/E2 isoform. HIV protease inhibitors may interfere with lipoprotein receptor related protein.  (+info)

Hyperlipoproteinemia Type III, also known as Broad Beta Disease or Remnant Hyperlipidemia, is a genetic disorder characterized by an increased level of chylomicron remnants and intermediate-density lipoproteins (IDL) in the blood. This results in elevated levels of both low-density lipoprotein (LDL), or "bad" cholesterol, and triglycerides, and decreased levels of high-density lipoprotein (HDL), or "good" cholesterol. The condition can lead to premature atherosclerosis and an increased risk for cardiovascular disease. It is caused by mutations in the APOE gene, which encodes the apolipoprotein E protein, leading to abnormal clearance of lipoproteins from the blood.

Hyperlipoproteinemia Type V is a rare genetic disorder characterized by an excess of lipids (fats) in the blood. It is caused by mutations in genes responsible for the metabolism of lipoproteins, which are particles that transport fat molecules, such as cholesterol and triglycerides, throughout the body.

In Hyperlipoproteinemia Type V, there is a significant increase in the levels of both chylomicrons (lipoprotein particles that carry dietary lipids) and very low-density lipoproteins (VLDLs, lipoprotein particles that carry endogenous lipids produced by the liver). This results in extremely high levels of triglycerides and moderately elevated levels of cholesterol in the blood.

Individuals with Hyperlipoproteinemia Type V are at an increased risk for developing pancreatitis (inflammation of the pancreas), eruptive xanthomas (small, yellowish bumps on the skin caused by cholesterol deposits), and hepatosplenomegaly (enlargement of the liver and spleen). The diagnosis is typically made based on clinical presentation, family history, and laboratory tests that measure lipid levels. Treatment often involves dietary modifications, weight loss, exercise, and medications to lower lipid levels in the blood.

Hyperlipoproteinemia Type I, also known as Familial Lipoprotein Lipase Deficiency, is a rare genetic disorder characterized by an absence or deficiency of the enzyme lipoprotein lipase. This enzyme is responsible for breaking down chylomicrons, which are large lipoprotein particles that transport dietary triglycerides from the intestines to the liver and peripheral tissues.

As a result of this deficiency, chylomicrons accumulate in the bloodstream, leading to elevated levels of triglycerides (hypertriglyceridemia) and chylomicrons (chylomiconemia). This condition can cause eruptive xanthomas, which are collections of lipid-laden foam cells that form under the skin, and recurrent pancreatitis, which is inflammation of the pancreas.

Hyperlipoproteinemia Type I is inherited in an autosomal recessive manner, meaning that an individual must inherit two copies of the mutated gene, one from each parent, to develop the condition. Treatment typically involves a low-fat diet and medications to reduce triglyceride levels.

Hyperlipoproteinemia Type IV is a genetic disorder characterized by an increased level of very low-density lipoproteins (VLDL) in the blood. This leads to elevated levels of triglycerides, which are a type of fat found in the blood. The condition is also sometimes referred to as "Fredrickson Type IV."

People with Hyperlipoproteinemia Type IV have an increased risk of developing pancreatitis, a potentially life-threatening inflammation of the pancreas, due to high levels of triglycerides. They may also have an increased risk of cardiovascular disease due to elevated levels of VLDL and other atherogenic lipoproteins.

The condition is usually inherited in an autosomal dominant manner, meaning that a child has a 50% chance of inheriting the disorder if one parent has it. However, some cases may be caused by mutations in multiple genes or by environmental factors such as obesity, diabetes, and excessive alcohol consumption.

Treatment for Hyperlipoproteinemia Type IV typically involves lifestyle modifications such as weight loss, exercise, and dietary changes to reduce triglyceride levels. In some cases, medication may be necessary to control the condition.

Hyperlipoproteinemias are medical conditions characterized by elevated levels of lipoproteins in the blood. Lipoproteins are particles that consist of proteins and lipids, which are responsible for transporting all fat molecules, such as cholesterol and triglycerides, around the body within the water outside cells. These lipids cannot dissolve in the blood, so they must be carried by these lipoprotein particles.

There are several types of hyperlipoproteinemias, classified based on the type of lipoprotein that is elevated and the pattern of inheritance. The most commonly recognized classification system is the Fredrickson classification, which includes five main types:

1. Type I - characterized by an excess of chylomicrons, a type of lipoprotein that carries dietary lipids, leading to extremely high levels of triglycerides in the blood. This rare disorder is usually caused by genetic mutations.
2. Type II - divided into two subtypes:
a. Type IIa - characterized by elevated LDL (low-density lipoprotein), or "bad" cholesterol, levels and often associated with premature cardiovascular disease. This condition can be caused by genetic factors, lifestyle choices, or both.
b. Type IIb - marked by increased levels of both LDL cholesterol and VLDL (very low-density lipoprotein), which leads to elevated triglycerides and cholesterol in the blood. This subtype can also be influenced by genetic factors, lifestyle choices, or both.
3. Type III - known as broad beta disease or remnant removal disease, this condition is characterized by an abnormal accumulation of remnant particles from VLDL and IDL (intermediate-density lipoprotein) metabolism, leading to increased levels of both cholesterol and triglycerides. This disorder can be caused by genetic mutations or secondary factors like diabetes, obesity, or hypothyroidism.
4. Type IV - characterized by elevated VLDL particles and high triglyceride levels in the blood. This condition is often associated with metabolic syndrome, obesity, diabetes, and alcohol consumption.
5. Type V - marked by increased VLDL and chylomicrons (lipoprotein particles that transport dietary lipids) in the blood, leading to extremely high triglyceride levels. This rare condition can be caused by genetic factors or secondary factors like diabetes, obesity, alcohol consumption, or uncontrolled lipid absorption.

It is important to note that these types are not mutually exclusive and can coexist in various combinations. Additionally, lifestyle choices such as diet, exercise, smoking, and alcohol consumption can significantly impact lipoprotein levels and contribute to the development of dyslipidemia (abnormal lipid levels).

Blood protein disorders refer to a group of medical conditions that affect the production or function of proteins in the blood. These proteins are crucial for maintaining the proper functioning of the body's immune system, transporting nutrients, and preventing excessive bleeding. Some examples of blood protein disorders include:

1. Hemophilia: A genetic disorder caused by a deficiency or absence of clotting factors in the blood, leading to prolonged bleeding and poor clot formation.
2. Von Willebrand disease: A genetic disorder characterized by abnormal or deficient von Willebrand factor, which is necessary for platelet function and proper clotting.
3. Dysproteinemias: Abnormal levels of certain proteins in the blood, such as immunoglobulins (antibodies) or paraproteins, which can indicate underlying conditions like multiple myeloma or macroglobulinemia.
4. Hypoproteinemia: Low levels of total protein in the blood, often caused by liver disease, malnutrition, or kidney disease.
5. Hyperproteinemia: Elevated levels of total protein in the blood, which can be caused by dehydration, inflammation, or certain types of cancer.
6. Hemoglobinopathies: Genetic disorders affecting the structure and function of hemoglobin, a protein found in red blood cells that carries oxygen throughout the body. Examples include sickle cell anemia and thalassemia.
7. Disorders of complement proteins: Abnormalities in the complement system, which is a group of proteins involved in the immune response, can lead to conditions like autoimmune disorders or recurrent infections.

Treatment for blood protein disorders varies depending on the specific condition and its severity but may include medications, transfusions, or other medical interventions.

Hyperlipoproteinemia Type II, also known as Fredrickson Type II or Familial Combined Hyperlipidemia, is a genetic disorder characterized by elevated levels of low-density lipoprotein (LDL) cholesterol and/or triglycerides in the blood. This condition can lead to an increased risk of developing cardiovascular diseases such as atherosclerosis and coronary artery disease.

The disorder is caused by mutations in several genes involved in lipid metabolism, including APOB, LDLR, PCSK9, and APOE. These genetic defects result in impaired clearance of LDL particles from the bloodstream, leading to their accumulation and increased risk of cardiovascular disease.

Individuals with Hyperlipoproteinemia Type II typically have elevated levels of both LDL cholesterol and triglycerides, although some may only have one or the other elevated. The disorder can present at any age, but it is often diagnosed in adulthood during routine cholesterol screening.

Treatment for Hyperlipoproteinemia Type II typically involves lifestyle modifications such as a heart-healthy diet, regular exercise, and weight loss. Medications such as statins, ezetimibe, and PCSK9 inhibitors may also be prescribed to lower LDL cholesterol levels and reduce the risk of cardiovascular disease.

Apolipoprotein E2 (ApoE2) is one of the three major isoforms of the apolipoprotein E (ApoE) protein, which is a component of lipoproteins that are involved in the transport and metabolism of cholesterol and other fats in the body. ApoE is produced by the APOE gene, which has three common alleles: ε2, ε3, and ε4.

The ApoE2 protein is encoded by the ε2 allele of the APOE gene. Compared to the other two isoforms (ApoE3 and ApoE4), ApoE2 has a different amino acid at position 112, where it has a cysteine instead of an arginine. This difference affects the protein's ability to interact with other molecules involved in lipid metabolism, such as the low-density lipoprotein receptor (LDLR).

Individuals who inherit two copies of the ε2 allele (ε2/ε2) have a higher risk of developing type III hyperlipoproteinemia, also known as dysbetalipoproteinemia, which is characterized by elevated levels of cholesterol and triglycerides in the blood due to impaired clearance of remnant lipoproteins. However, not all people with the ε2/ε2 genotype develop type III hyperlipoproteinemia, and other genetic and environmental factors may contribute to the development of this condition.

It's worth noting that having one or two copies of the ε2 allele has been associated with a reduced risk of developing Alzheimer's disease, although the mechanism by which ApoE2 protects against Alzheimer's is not fully understood.

VLDL (Very Low-Density Lipoproteins) are a type of lipoprotein that play a crucial role in the transport and metabolism of fat molecules, known as triglycerides, in the body. They are produced by the liver and consist of a core of triglycerides surrounded by a shell of proteins called apolipoproteins, phospholipids, and cholesterol.

VLDL particles are responsible for delivering fat molecules from the liver to peripheral tissues throughout the body, where they can be used as an energy source or stored for later use. During this process, VLDL particles lose triglycerides and acquire more cholesterol, transforming into intermediate-density lipoproteins (IDL) and eventually low-density lipoproteins (LDL), which are also known as "bad" cholesterol.

Elevated levels of VLDL in the blood can contribute to the development of cardiovascular disease due to their association with increased levels of triglycerides and LDL cholesterol, as well as decreased levels of high-density lipoproteins (HDL), which are considered "good" cholesterol.

Hyperlipidemias are a group of disorders characterized by an excess of lipids (fats) or lipoproteins in the blood. These include elevated levels of cholesterol, triglycerides, or both. Hyperlipidemias can be inherited (primary) or caused by other medical conditions (secondary). They are a significant risk factor for developing cardiovascular diseases, such as atherosclerosis and coronary artery disease.

There are two main types of lipids that are commonly measured in the blood: low-density lipoprotein (LDL) cholesterol, often referred to as "bad" cholesterol, and high-density lipoprotein (HDL) cholesterol, known as "good" cholesterol. High levels of LDL cholesterol can lead to the formation of plaques in the arteries, which can narrow or block them and increase the risk of heart attack or stroke. On the other hand, high levels of HDL cholesterol are protective because they help remove LDL cholesterol from the bloodstream.

Triglycerides are another type of lipid that can be measured in the blood. Elevated triglyceride levels can also contribute to the development of cardiovascular disease, particularly when combined with high LDL cholesterol and low HDL cholesterol levels.

Hyperlipidemias are typically diagnosed through a blood test that measures the levels of various lipids and lipoproteins in the blood. Treatment may include lifestyle changes, such as following a healthy diet, getting regular exercise, losing weight, and quitting smoking, as well as medication to lower lipid levels if necessary.

Xanthomatosis is a medical term that refers to the condition characterized by the presence of xanthomas, which are yellowish, fat-laden deposits that form under the skin or in other tissues. These deposits consist of lipids, such as cholesterol and triglycerides, and immune cells called macrophages, which have engulfed the lipids.

Xanthomas can occur in various parts of the body, including the eyelids, tendons, joints, and other areas with connective tissue. They may appear as small papules or larger nodules, and their size and number can vary depending on the severity of the underlying disorder.

Xanthomatosis is often associated with genetic disorders that affect lipid metabolism, such as familial hypercholesterolemia, or with acquired conditions that cause high levels of lipids in the blood, such as diabetes, hypothyroidism, and certain liver diseases. Treatment typically involves addressing the underlying disorder and controlling lipid levels through dietary changes, medications, or a combination of both.

Apolipoprotein E (ApoE) is a protein involved in the metabolism of lipids, particularly cholesterol. It is produced primarily by the liver and is a component of several types of lipoproteins, including very low-density lipoproteins (VLDL) and high-density lipoproteins (HDL).

ApoE plays a crucial role in the transport and uptake of lipids in the body. It binds to specific receptors on cell surfaces, facilitating the delivery of lipids to cells for energy metabolism or storage. ApoE also helps to clear cholesterol from the bloodstream and is involved in the repair and maintenance of tissues.

There are three major isoforms of ApoE, designated ApoE2, ApoE3, and ApoE4, which differ from each other by only a few amino acids. These genetic variations can have significant effects on an individual's risk for developing certain diseases, particularly cardiovascular disease and Alzheimer's disease. For example, individuals who inherit the ApoE4 allele have an increased risk of developing Alzheimer's disease, while those with the ApoE2 allele may have a reduced risk.

In summary, Apolipoprotein E is a protein involved in lipid metabolism and transport, and genetic variations in this protein can influence an individual's risk for certain diseases.

Triglycerides are the most common type of fat in the body, and they're found in the food we eat. They're carried in the bloodstream to provide energy to the cells in our body. High levels of triglycerides in the blood can increase the risk of heart disease, especially in combination with other risk factors such as high LDL (bad) cholesterol, low HDL (good) cholesterol, and high blood pressure.

It's important to note that while triglycerides are a type of fat, they should not be confused with cholesterol, which is a waxy substance found in the cells of our body. Both triglycerides and cholesterol are important for maintaining good health, but high levels of either can increase the risk of heart disease.

Triglyceride levels are measured through a blood test called a lipid panel or lipid profile. A normal triglyceride level is less than 150 mg/dL. Borderline-high levels range from 150 to 199 mg/dL, high levels range from 200 to 499 mg/dL, and very high levels are 500 mg/dL or higher.

Elevated triglycerides can be caused by various factors such as obesity, physical inactivity, excessive alcohol consumption, smoking, and certain medical conditions like diabetes, hypothyroidism, and kidney disease. Medications such as beta-blockers, steroids, and diuretics can also raise triglyceride levels.

Lifestyle changes such as losing weight, exercising regularly, eating a healthy diet low in saturated and trans fats, avoiding excessive alcohol consumption, and quitting smoking can help lower triglyceride levels. In some cases, medication may be necessary to reduce triglycerides to recommended levels.

Lipoproteins are complex particles composed of multiple proteins and lipids (fats) that play a crucial role in the transport and metabolism of fat molecules in the body. They consist of an outer shell of phospholipids, free cholesterols, and apolipoproteins, enclosing a core of triglycerides and cholesteryl esters.

There are several types of lipoproteins, including:

1. Chylomicrons: These are the largest lipoproteins and are responsible for transporting dietary lipids from the intestines to other parts of the body.
2. Very-low-density lipoproteins (VLDL): Produced by the liver, VLDL particles carry triglycerides to peripheral tissues for energy storage or use.
3. Low-density lipoproteins (LDL): Often referred to as "bad cholesterol," LDL particles transport cholesterol from the liver to cells throughout the body. High levels of LDL in the blood can lead to plaque buildup in artery walls and increase the risk of heart disease.
4. High-density lipoproteins (HDL): Known as "good cholesterol," HDL particles help remove excess cholesterol from cells and transport it back to the liver for excretion or recycling. Higher levels of HDL are associated with a lower risk of heart disease.

Understanding lipoproteins and their roles in the body is essential for assessing cardiovascular health and managing risks related to heart disease and stroke.

Apolipoprotein E3 (ApoE3) is one of the three major isoforms of apolipoprotein E (ApoE), a protein involved in the metabolism of lipids, particularly cholesterol. ApoE is produced by the APOE gene, which has three common alleles: ε2, ε3, and ε4. These alleles result in three main isoforms of the protein: ApoE2, ApoE3, and ApoE4.

ApoE3 is the most common isoform, found in approximately 77-78% of the population. It has a slightly different amino acid sequence compared to ApoE2 and ApoE4, which can affect its function. ApoE3 is thought to play a neutral or protective role in the risk of developing Alzheimer's disease and cardiovascular diseases, although some studies suggest that it may have a mildly favorable effect on lipid metabolism compared to ApoE4.

Familial Combined Hyperlipidemia (FCH) is a genetic disorder characterized by high levels of cholesterol and/or fats (lipids) in the blood. It is one of the most common inherited lipid disorders, affecting approximately 1 in 200 to 1 in 500 people.

FCH is caused by mutations in several genes involved in lipid metabolism, including the APOB, LDLR, and PCSK9 genes. These genetic defects lead to increased levels of low-density lipoprotein (LDL) cholesterol, triglycerides, or both in the blood.

Individuals with FCH may have elevated levels of total cholesterol, LDL cholesterol, and/or triglycerides, which can increase their risk for premature atherosclerosis and cardiovascular disease. The condition often presents in early adulthood and may manifest as mixed hyperlipidemia (high levels of both LDL cholesterol and triglycerides) or isolated hypercholesterolemia (high levels of LDL cholesterol only).

Familial combined hyperlipidemia is typically managed with lifestyle modifications, such as a heart-healthy diet, regular exercise, and weight management. Medications, such as statins, may also be prescribed to lower lipid levels and reduce the risk of cardiovascular disease. Regular monitoring of lipid levels is essential for effective management and prevention of complications associated with FCH.

Cholesterol is a type of lipid (fat) molecule that is an essential component of cell membranes and is also used to make certain hormones and vitamins in the body. It is produced by the liver and is also obtained from animal-derived foods such as meat, dairy products, and eggs.

Cholesterol does not mix with blood, so it is transported through the bloodstream by lipoproteins, which are particles made up of both lipids and proteins. There are two main types of lipoproteins that carry cholesterol: low-density lipoproteins (LDL), also known as "bad" cholesterol, and high-density lipoproteins (HDL), also known as "good" cholesterol.

High levels of LDL cholesterol in the blood can lead to a buildup of cholesterol in the walls of the arteries, increasing the risk of heart disease and stroke. On the other hand, high levels of HDL cholesterol are associated with a lower risk of these conditions because HDL helps remove LDL cholesterol from the bloodstream and transport it back to the liver for disposal.

It is important to maintain healthy levels of cholesterol through a balanced diet, regular exercise, and sometimes medication if necessary. Regular screening is also recommended to monitor cholesterol levels and prevent health complications.

Lipoprotein lipase (LPL) is an enzyme that plays a crucial role in the metabolism of lipids. It is responsible for breaking down triglycerides, which are the main constituent of dietary fats and chylomicrons, into fatty acids and glycerol. These products are then taken up by cells for energy production or storage.

LPL is synthesized in various tissues, including muscle and fat, where it is attached to the inner lining of blood vessels (endothelium). The enzyme is activated when it comes into contact with lipoprotein particles, such as chylomicrons and very-low-density lipoproteins (VLDL), which transport triglycerides in the bloodstream.

Deficiencies or mutations in LPL can lead to various metabolic disorders, including hypertriglyceridemia, a condition characterized by high levels of triglycerides in the blood. Conversely, overexpression of LPL has been associated with increased risk of atherosclerosis due to excessive uptake of fatty acids by macrophages and their conversion into foam cells, which contribute to plaque formation in the arteries.

Apolipoproteins are a group of proteins that are associated with lipids (fats) in the body and play a crucial role in the metabolism, transportation, and regulation of lipids. They are structural components of lipoprotein particles, which are complexes of lipids and proteins that transport lipids in the bloodstream.

There are several types of apolipoproteins, including ApoA, ApoB, ApoC, ApoD, ApoE, and others. Each type has a specific function in lipid metabolism. For example, ApoA is a major component of high-density lipoprotein (HDL), often referred to as "good cholesterol," and helps remove excess cholesterol from cells and tissues and transport it to the liver for excretion. ApoB, on the other hand, is a major component of low-density lipoprotein (LDL), or "bad cholesterol," and plays a role in the delivery of cholesterol to cells and tissues.

Abnormal levels of apolipoproteins or dysfunctional forms of these proteins have been linked to various diseases, including cardiovascular disease, Alzheimer's disease, and metabolic disorders such as diabetes. Therefore, measuring apolipoprotein levels in the blood can provide valuable information for diagnosing and monitoring these conditions.

Low-density lipoproteins (LDL), also known as "bad cholesterol," are a type of lipoprotein that carry cholesterol and other fats from the liver to cells throughout the body. High levels of LDL in the blood can lead to the buildup of cholesterol in the walls of the arteries, which can increase the risk of heart disease and stroke.

Lipoproteins are complex particles composed of proteins (apolipoproteins) and lipids (cholesterol, triglycerides, and phospholipids) that are responsible for transporting fat molecules around the body in the bloodstream. LDL is one type of lipoprotein, along with high-density lipoproteins (HDL), very low-density lipoproteins (VLDL), and chylomicrons.

LDL particles are smaller than HDL particles and can easily penetrate the artery walls, leading to the formation of plaques that can narrow or block the arteries. Therefore, maintaining healthy levels of LDL in the blood is essential for preventing cardiovascular disease.

Chylomicrons are a type of lipoprotein that are responsible for carrying dietary lipids, such as triglycerides and cholesterol, from the intestines to other parts of the body through the lymphatic system and bloodstream. They are the largest lipoproteins and are composed of an outer layer of phospholipids, free cholesterol, and apolipoproteins, which surrounds a core of triglycerides and cholesteryl esters. Chylomicrons are produced in the intestinal mucosa after a meal containing fat, and their production is stimulated by the hormone cholecystokinin. Once in the bloodstream, chylomicrons interact with other lipoproteins and enzymes to deliver their lipid cargo to various tissues, including muscle and adipose tissue, where they are used for energy or stored for later use.

Apolipoprotein C (apoC) is a group of proteins that are associated with lipoproteins, which are complex particles composed of lipids and proteins that play a crucial role in the transport and metabolism of lipids in the body. There are three main types of apoC proteins: apoC-I, apoC-II, and apoC-III.

ApoC-I is involved in the regulation of lipoprotein metabolism and has been shown to inhibit the activity of cholesteryl ester transfer protein (CETP), which is an enzyme that facilitates the transfer of cholesteryl esters from high-density lipoproteins (HDL) to low-density lipoproteins (LDL) and very low-density lipoproteins (VLDL).

ApoC-II is a cofactor for lipoprotein lipase, an enzyme that hydrolyzes triglycerides in chylomicrons and VLDL, leading to the formation of smaller, denser lipoproteins. A deficiency in apoC-II can lead to hypertriglyceridemia, a condition characterized by elevated levels of triglycerides in the blood.

ApoC-III is also involved in the regulation of lipoprotein metabolism and has been shown to inhibit the activity of lipoprotein lipase and CETP. Elevated levels of apoC-III have been associated with an increased risk of cardiovascular disease, possibly due to its effects on lipoprotein metabolism.

In summary, apolipoprotein C is a group of proteins that are involved in the regulation of lipoprotein metabolism and have important roles in the transport and metabolism of lipids in the body.

Blood protein electrophoresis (BPE) is a laboratory test that separates and measures the different proteins in the blood, such as albumin, alpha-1 globulins, alpha-2 globulins, beta globulins, and gamma globulins. This test is often used to help diagnose or monitor conditions related to abnormal protein levels, such as multiple myeloma, macroglobulinemia, and other plasma cell disorders.

In this test, a sample of the patient's blood is placed on a special gel and an electric current is applied. The proteins in the blood migrate through the gel based on their electrical charge and size, creating bands that can be visualized and measured. By comparing the band patterns to reference ranges, doctors can identify any abnormal protein levels or ratios, which may indicate underlying medical conditions.

It's important to note that while BPE is a useful diagnostic tool, it should be interpreted in conjunction with other clinical findings and laboratory tests for accurate diagnosis and management of the patient's condition.

VLDL, or very low-density lipoproteins, are a type of lipoprotein that carries triglycerides and cholesterol from the liver to other parts of the body. Cholesterol is a fatty substance found in the blood, and VLDL contains both triglycerides and cholesterol.

Cholesterol itself cannot dissolve in the blood and needs to be transported around the body by lipoproteins, which are protein molecules that encapsulate and carry fat molecules, such as cholesterol and triglycerides, through the bloodstream. VLDL is one of several types of lipoproteins, including low-density lipoproteins (LDL) and high-density lipoproteins (HDL).

Elevated levels of VLDL in the blood can contribute to the development of atherosclerosis, a condition characterized by the buildup of plaque in the arteries, which can increase the risk of heart disease and stroke. Therefore, maintaining healthy levels of VLDL and other lipoproteins is an important part of overall cardiovascular health.

Collagen Type III, also known as Collagen III Alpha 1 (COL3A1), is a type of collagen that is found in various connective tissues throughout the body. It is a fibrillar collagen that is produced by fibroblasts and is a major component of reticular fibers, which provide structural support to organs such as the liver, spleen, and lymph nodes. Collagen Type III is also found in the walls of blood vessels, the skin, and the intestinal tract.

Mutations in the COL3A1 gene can lead to a rare genetic disorder called Ehlers-Danlos syndrome type IV, which is characterized by fragile and elastic skin, easy bruising, and spontaneous rupture of blood vessels. Collagen Type III has been studied for its potential role in various other medical conditions, including fibrosis, cancer, and cardiovascular disease.

LDL receptors (Low-Density Lipoprotein Receptors) are cell surface receptors that play a crucial role in the regulation of cholesterol homeostasis within the body. They are responsible for recognizing and binding to LDL particles, also known as "bad cholesterol," which are then internalized by the cell through endocytosis.

Once inside the cell, the LDL particles are broken down, releasing their cholesterol content, which can be used for various cellular processes such as membrane synthesis and hormone production. The LDL receptors themselves are recycled back to the cell surface, allowing for continued uptake of LDL particles.

Mutations in the LDL receptor gene can lead to a condition called familial hypercholesterolemia, which is characterized by high levels of LDL cholesterol in the blood and an increased risk of premature cardiovascular disease.

Paper electrophoresis is a laboratory technique used to separate and analyze mixtures of charged particles, such as proteins or nucleic acids (DNA or RNA), based on their differing rates of migration in an electric field. In this method, the sample is applied to a strip of paper, usually made of cellulose, which is then placed in a bath of electrophoresis buffer.

An electric current is applied across the bath, creating an electric field that causes the charged particles in the sample to migrate along the length of the paper. The rate of migration depends on the charge and size of the particle: more highly charged particles move faster, while larger particles move more slowly. This allows for the separation of the individual components of the mixture based on their electrophoretic mobility.

After the electrophoresis is complete, the separated components can be visualized using various staining techniques, such as protein stains for proteins or dyes specific to nucleic acids. The resulting pattern of bands can then be analyzed to identify and quantify the individual components in the mixture.

Paper electrophoresis has been largely replaced by other methods, such as slab gel electrophoresis, due to its lower resolution and limited separation capabilities. However, it is still used in some applications where a simple, rapid, and low-cost method is desired.

Apolipoprotein C-II (ApoC-II) is a type of apolipoprotein, which are proteins that bind to lipids to form lipoprotein complexes. ApoC-II is a component of several lipoproteins, including very low-density lipoproteins (VLDL) and chylomicrons, which are responsible for the transport of fat molecules, such as triglycerides and cholesterol, in the bloodstream.

ApoC-II plays a crucial role in the activation of lipoprotein lipase, an enzyme that breaks down triglycerides in VLDL and chylomicrons into fatty acids, which can then be taken up by cells for energy production or storage. Therefore, ApoC-II deficiency can lead to hypertriglyceridemia, a condition characterized by high levels of triglycerides in the blood.

In addition to its role in lipid metabolism, ApoC-II has been implicated in the development and progression of atherosclerosis, a chronic inflammatory disease that affects the arteries and can lead to serious cardiovascular complications, such as heart attack and stroke.

Gemfibrozil is a medication that belongs to a class of drugs called fibrates. It is primarily used to lower elevated levels of triglycerides (a type of fat found in the blood) and increase levels of "good" cholesterol (HDL-C) in the blood.

Gemfibrozil works by reducing the production of triglycerides in the body, increasing the breakdown of fats in the liver, and improving the way the body handles fats and sugar. It is often prescribed for people with high triglyceride levels who are at risk for pancreatitis (inflammation of the pancreas) or those who have not responded well to other cholesterol-lowering medications, such as statins.

It's important to note that while gemfibrozil can help manage triglyceride and cholesterol levels, it is not a substitute for a healthy lifestyle. Regular exercise, a balanced diet, limiting alcohol consumption, and avoiding smoking are all crucial components of maintaining good cardiovascular health.

As with any medication, gemfibrozil should be taken under the supervision of a healthcare provider, who can monitor its effectiveness and potential side effects. Common side effects of gemfibrozil include stomach pain, diarrhea, and muscle or joint pain. Rare but serious side effects may include liver damage, kidney problems, and an increased risk of gallstones.

Hypertriglyceridemia is a medical condition characterized by an elevated level of triglycerides in the blood. Triglycerides are a type of fat (lipid) found in your blood that can increase the risk of developing heart disease, especially when levels are very high.

In general, hypertriglyceridemia is defined as having triglyceride levels greater than 150 milligrams per deciliter (mg/dL) of blood. However, the specific definition of hypertriglyceridemia may vary depending on individual risk factors and medical history.

Hypertriglyceridemia can be caused by a variety of factors, including genetics, obesity, physical inactivity, excessive alcohol consumption, and certain medications. In some cases, it may also be a secondary consequence of other medical conditions such as diabetes or hypothyroidism. Treatment for hypertriglyceridemia typically involves lifestyle modifications such as dietary changes, increased exercise, and weight loss, as well as medication if necessary.

Chenodeoxycholic acid (CDCA) is a bile acid that is naturally produced in the human body. It is formed in the liver from cholesterol and is then conjugated with glycine or taurine to become a primary bile acid. CDCA is stored in the gallbladder and released into the small intestine during digestion, where it helps to emulsify fats and facilitate their absorption.

CDCA also has important regulatory functions in the body, including acting as a signaling molecule that binds to specific receptors in the liver, intestines, and other tissues. It plays a role in glucose and lipid metabolism, inflammation, and cell growth and differentiation.

In addition to its natural functions, CDCA is also used as a medication for the treatment of certain medical conditions. For example, it is used to dissolve gallstones that are composed of cholesterol, and it is also used to treat a rare genetic disorder called cerebrotendinous xanthomatosis (CTX), which is characterized by the accumulation of CDCA and other bile acids in various tissues.

It's important to note that while CDCA has therapeutic uses, it can also have adverse effects if taken in high doses or for extended periods of time. Therefore, it should only be used under the supervision of a healthcare professional.

Cholic acids are a type of bile acid, which are naturally occurring steroid acids that play a crucial role in the digestion and absorption of fats and fat-soluble vitamins in the body. Cholic acid is the primary bile acid synthesized in the liver from cholesterol. It is then conjugated with glycine or taurine to form conjugated cholic acids, which are stored in the gallbladder and released into the small intestine during digestion to aid in fat emulsification and absorption.

Cholic acid and its derivatives have also been studied for their potential therapeutic benefits in various medical conditions, including liver diseases, gallstones, and bacterial infections. However, more research is needed to fully understand the mechanisms of action and potential side effects of cholic acids and their derivatives before they can be widely used as therapeutic agents.

Ultracentrifugation is a medical and laboratory technique used for the separation of particles of different sizes, densities, or shapes from a mixture based on their sedimentation rates. This process involves the use of a specialized piece of equipment called an ultracentrifuge, which can generate very high centrifugal forces, much greater than those produced by a regular centrifuge.

In ultracentrifugation, a sample is placed in a special tube and spun at extremely high speeds, causing the particles within the sample to separate based on their size, shape, and density. The larger or denser particles will sediment faster and accumulate at the bottom of the tube, while smaller or less dense particles will remain suspended in the solution or sediment more slowly.

Ultracentrifugation is a valuable tool in various fields, including biochemistry, molecular biology, and virology. It can be used to purify and concentrate viruses, subcellular organelles, membrane fractions, ribosomes, DNA, and other macromolecules from complex mixtures. The technique can also provide information about the size, shape, and density of these particles, making it a crucial method for characterizing and studying their properties.

High-Density Lipoproteins (HDL) are a type of lipoprotein that play a crucial role in the transportation and metabolism of cholesterol in the body. They are often referred to as "good" cholesterol because they help remove excess cholesterol from cells and carry it back to the liver, where it can be broken down and removed from the body. This process is known as reverse cholesterol transport.

HDLs are composed of a lipid core containing cholesteryl esters and triglycerides, surrounded by a shell of phospholipids, free cholesterol, and apolipoproteins, primarily apoA-I. The size and composition of HDL particles can vary, leading to the classification of different subclasses of HDL with varying functions and metabolic fates.

Elevated levels of HDL have been associated with a lower risk of developing cardiovascular diseases, while low HDL levels increase the risk. However, it is essential to consider that HDL function and quality may be more important than just the quantity in determining cardiovascular risk.

Heparin is defined as a highly sulfated glycosaminoglycan (a type of polysaccharide) that is widely present in many tissues, but is most commonly derived from the mucosal tissues of mammalian lungs or intestinal mucosa. It is an anticoagulant that acts as an inhibitor of several enzymes involved in the blood coagulation cascade, primarily by activating antithrombin III which then neutralizes thrombin and other clotting factors.

Heparin is used medically to prevent and treat thromboembolic disorders such as deep vein thrombosis, pulmonary embolism, and certain types of heart attacks. It can also be used during hemodialysis, cardiac bypass surgery, and other medical procedures to prevent the formation of blood clots.

It's important to note that while heparin is a powerful anticoagulant, it does not have any fibrinolytic activity, meaning it cannot dissolve existing blood clots. Instead, it prevents new clots from forming and stops existing clots from growing larger.

Apolipoprotein C-III (APOC3) is a protein that is produced in the liver and circulates in the bloodstream. It is a component of certain lipoproteins, including very low-density lipoproteins (VLDL) and chylomicrons, which are responsible for transporting fat molecules, such as triglycerides and cholesterol, throughout the body.

APOC3 plays a role in regulating the metabolism of these lipoproteins. Specifically, it inhibits the activity of an enzyme called lipoprotein lipase, which breaks down triglycerides in VLDL and chylomicrons. As a result, high levels of APOC3 can lead to an increase in triglyceride levels in the blood, which is a risk factor for cardiovascular disease.

Genetic variations in the APOC3 gene have been associated with differences in triglyceride levels and risk of cardiovascular disease. Some studies have suggested that reducing APOC3 levels through genetic editing or other means may be a promising strategy for lowering triglycerides and reducing the risk of heart disease.

Lipids are a broad group of organic compounds that are insoluble in water but soluble in nonpolar organic solvents. They include fats, waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E, and K), monoglycerides, diglycerides, triglycerides, and phospholipids. Lipids serve many important functions in the body, including energy storage, acting as structural components of cell membranes, and serving as signaling molecules. High levels of certain lipids, particularly cholesterol and triglycerides, in the blood are associated with an increased risk of cardiovascular disease.

Electrophoresis, Agar Gel is a laboratory technique used to separate and analyze DNA, RNA, or proteins based on their size and electrical charge. In this method, the sample is mixed with agarose gel, a gelatinous substance derived from seaweed, and then solidified in a horizontal slab-like format. An electric field is applied to the gel, causing the negatively charged DNA or RNA molecules to migrate towards the positive electrode. The smaller molecules move faster through the gel than the larger ones, resulting in their separation based on size. This technique is widely used in molecular biology and genetics research, as well as in diagnostic testing for various genetic disorders.

Lipase is an enzyme that is produced by the pancreas and found in the digestive system of most organisms. Its primary function is to catalyze the hydrolysis of fats (triglycerides) into smaller molecules, such as fatty acids and glycerol, which can then be absorbed by the intestines and utilized for energy or stored for later use.

In medical terms, lipase levels in the blood are often measured to diagnose or monitor conditions that affect the pancreas, such as pancreatitis (inflammation of the pancreas), pancreatic cancer, or cystic fibrosis. Elevated lipase levels may indicate damage to the pancreas and its ability to produce digestive enzymes.

Dietary cholesterol is a type of cholesterol that comes from the foods we eat. It is present in animal-derived products such as meat, poultry, dairy products, and eggs. While dietary cholesterol can contribute to an increase in blood cholesterol levels for some people, it's important to note that saturated and trans fats have a more significant impact on blood cholesterol levels than dietary cholesterol itself.

The American Heart Association recommends limiting dietary cholesterol intake to less than 300 milligrams per day for most people, and less than 200 milligrams per day for those with a history of heart disease or high cholesterol levels. However, individual responses to dietary cholesterol can vary, so it's essential to monitor blood cholesterol levels and adjust dietary habits accordingly.

Isoelectric focusing (IEF) is a technique used in electrophoresis, which is a method for separating proteins or other molecules based on their electrical charges. In IEF, a mixture of ampholytes (molecules that can carry both positive and negative charges) is used to create a pH gradient within a gel matrix. When an electric field is applied, the proteins or molecules migrate through the gel until they reach the point in the gradient where their net charge is zero, known as their isoelectric point (pI). At this point, they focus into a sharp band and stop moving, resulting in a highly resolved separation of the different components based on their pI. This technique is widely used in protein research for applications such as protein identification, characterization, and purification.

A phenotype is the physical or biochemical expression of an organism's genes, or the observable traits and characteristics resulting from the interaction of its genetic constitution (genotype) with environmental factors. These characteristics can include appearance, development, behavior, and resistance to disease, among others. Phenotypes can vary widely, even among individuals with identical genotypes, due to differences in environmental influences, gene expression, and genetic interactions.

A homozygote is an individual who has inherited the same allele (version of a gene) from both parents and therefore possesses two identical copies of that allele at a specific genetic locus. This can result in either having two dominant alleles (homozygous dominant) or two recessive alleles (homozygous recessive). In contrast, a heterozygote has inherited different alleles from each parent for a particular gene.

The term "homozygote" is used in genetics to describe the genetic makeup of an individual at a specific locus on their chromosomes. Homozygosity can play a significant role in determining an individual's phenotype (observable traits), as having two identical alleles can strengthen the expression of certain characteristics compared to having just one dominant and one recessive allele.

I must clarify that the term "pedigree" is not typically used in medical definitions. Instead, it is often employed in genetics and breeding, where it refers to the recorded ancestry of an individual or a family, tracing the inheritance of specific traits or diseases. In human genetics, a pedigree can help illustrate the pattern of genetic inheritance in families over multiple generations. However, it is not a medical term with a specific clinical definition.

Apolipoprotein B (ApoB) is a type of protein that plays a crucial role in the metabolism of lipids, particularly low-density lipoprotein (LDL) or "bad" cholesterol. ApoB is a component of LDL particles and serves as a ligand for the LDL receptor, which is responsible for the clearance of LDL from the bloodstream.

There are two main forms of ApoB: ApoB-100 and ApoB-48. ApoB-100 is found in LDL particles, very low-density lipoprotein (VLDL) particles, and chylomicrons, while ApoB-48 is only found in chylomicrons, which are produced in the intestines and responsible for transporting dietary lipids.

Elevated levels of ApoB are associated with an increased risk of cardiovascular disease (CVD), as they indicate a higher concentration of LDL particles in the bloodstream. Therefore, measuring ApoB levels can provide additional information about CVD risk beyond traditional lipid profile tests that only measure total cholesterol, LDL cholesterol, HDL cholesterol, and triglycerides.

Electrophoresis is a laboratory technique used in the field of molecular biology and chemistry to separate charged particles, such as DNA, RNA, or proteins, based on their size and charge. This technique uses an electric field to drive the movement of these charged particles through a medium, such as gel or liquid.

In electrophoresis, the sample containing the particles to be separated is placed in a matrix, such as a gel or a capillary tube, and an electric current is applied. The particles in the sample have a net charge, either positive or negative, which causes them to move through the matrix towards the oppositely charged electrode.

The rate at which the particles move through the matrix depends on their size and charge. Larger particles move more slowly than smaller ones, and particles with a higher charge-to-mass ratio move faster than those with a lower charge-to-mass ratio. By comparing the distance that each particle travels in the matrix, researchers can identify and quantify the different components of a mixture.

Electrophoresis has many applications in molecular biology and medicine, including DNA sequencing, genetic fingerprinting, protein analysis, and diagnosis of genetic disorders.

Apoproteins are the protein components of lipoprotein complexes, which are responsible for transporting fat molecules, such as cholesterol and triglycerides, throughout the body. Apoproteins play a crucial role in the metabolism of lipids by acting as recognition signals that allow lipoproteins to interact with specific receptors on cell surfaces.

There are several different types of apoproteins, each with distinct functions. For example, apolipoprotein A-1 (apoA-1) is the major protein component of high-density lipoproteins (HDL), which are responsible for transporting excess cholesterol from tissues to the liver for excretion. Apolipoprotein B (apoB) is a large apoprotein found in low-density lipoproteins (LDL), very low-density lipoproteins (VLDL), and lipoprotein(a). ApoB plays a critical role in the assembly and secretion of VLDL from the liver, and it also mediates the uptake of LDL by cells.

Abnormalities in apoprotein levels or function can contribute to the development of various diseases, including cardiovascular disease, diabetes, and Alzheimer's disease. Therefore, measuring apoprotein levels in the blood can provide valuable information for diagnosing and monitoring these conditions.

Hypercholesterolemia is a medical term that describes a condition characterized by high levels of cholesterol in the blood. Specifically, it refers to an abnormally elevated level of low-density lipoprotein (LDL) cholesterol, also known as "bad" cholesterol, which can contribute to the development of fatty deposits in the arteries called plaques. Over time, these plaques can narrow and harden the arteries, leading to atherosclerosis, a condition that increases the risk of heart disease, stroke, and other cardiovascular complications.

Hypercholesterolemia can be caused by various factors, including genetics, lifestyle choices, and underlying medical conditions. In some cases, it may not cause any symptoms until serious complications arise. Therefore, regular cholesterol screening is essential for early detection and management of hypercholesterolemia. Treatment typically involves lifestyle modifications, such as a healthy diet, regular exercise, and weight management, along with medication if necessary.

Arteriosclerosis is a general term that describes the hardening and stiffening of the artery walls. It's a progressive condition that can occur as a result of aging, or it may be associated with certain risk factors such as high blood pressure, high cholesterol, diabetes, smoking, and a sedentary lifestyle.

The process of arteriosclerosis involves the buildup of plaque, made up of fat, cholesterol, calcium, and other substances, in the inner lining of the artery walls. Over time, this buildup can cause the artery walls to thicken and harden, reducing the flow of oxygen-rich blood to the body's organs and tissues.

Arteriosclerosis can affect any of the body's arteries, but it is most commonly found in the coronary arteries that supply blood to the heart, the cerebral arteries that supply blood to the brain, and the peripheral arteries that supply blood to the limbs. When arteriosclerosis affects the coronary arteries, it can lead to heart disease, angina, or heart attack. When it affects the cerebral arteries, it can lead to stroke or transient ischemic attack (TIA). When it affects the peripheral arteries, it can cause pain, numbness, or weakness in the limbs, and in severe cases, gangrene and amputation.

Apolipoprotein A (apoA) is a type of apolipoprotein that is primarily associated with high-density lipoproteins (HDL), often referred to as "good cholesterol." There are several subtypes of apoA, including apoA-I, apoA-II, and apoA-IV.

ApoA-I is the major protein component of HDL particles and plays a crucial role in reverse cholesterol transport, which is the process by which excess cholesterol is removed from tissues and delivered to the liver for excretion. Low levels of apoA-I have been linked to an increased risk of cardiovascular disease.

ApoA-II is another protein component of HDL particles, although its function is less well understood than that of apoA-I. Some studies suggest that apoA-II may play a role in regulating the metabolism of HDL particles.

ApoA-IV is found in both HDL and chylomicrons, which are lipoprotein particles that transport dietary lipids from the intestine to the liver. The function of apoA-IV is not well understood, but it may play a role in regulating appetite and energy metabolism.

Overall, apolipoproteins A are important components of HDL particles and play a critical role in maintaining healthy lipid metabolism and reducing the risk of cardiovascular disease.

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