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Any complex of fats with protein. A conjugated protein consisting of a simple protein combined with a fat (lipid) group. The blood lipoproteins, which are the cholesterol carriers of the body, are classified by density, in accordance with the proportions of protein, as very low density (VLDL), low density (LDL) and high density (HDL). LDLs contain relatively large amounts of cholesterol. HDLs contain 50% of protein and only 20% of cholesterol. LDLs transport lipids to muscles and to fat stores and are associated with the arterial disease ATHEROSCLEROSIS and thus heart disease and STROKE. HDLs are protective against these diseases because their main role is to transport cholesterol from the periphery back to the liver. They also carry paraoxanase enzymes that limit oxidative modification of LDLs necessary before cholesterol can be laid down in arterial walls. Blood concentration of HDL cholesterol shows a strong inverse correlation with the risk of coronary heart disease.


The packages in which cholesterol and triglycerides travel throughout the body.
Mentioned in: Lipoproteins Test


(lip´ōprō´tēns), biochemical compounds that contain both lipid and protein. Most lipids in plasma are present in the form of lipoproteins. There are two main types: low density and high density.
lipoproteins, high-density (HDLs), the types containing approximately 50% protein that transport cholesterol to the liver for disposal. High HDL levels are associated with low body cholesterol and decreased risk of heart disease.
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Lipoma of the lip.
lipoproteins, low-density (LDLs), the types containing approximately 21% protein that deliver cholesterol from the liver to cells throughout the body. High amounts of LDLs may raise cholesterol levels in the body and increase the risk of developing atherosclerosis.

Patient discussion about lipoproteins

Q. what are the sources for high density lipoprotein? I have heard that high density lipoprotein is good for heart. What differences does it make in heart’s health and what are the sources for high density lipoprotein?

A. Hi Liam, it is very important that we have high density lipoprotein (HDL) in our body. The fact is that the HDL is formed inside the body. They are known as good cholesterol as they are famous for their protection for heart against the heart diseases. It has been found that Vitamin B3 or Niacin consumption increases the count of HDL. It’s good to cut on the diet having more of saturated fats and oils, which increases the chances of heart attack.

More discussions about lipoproteins
References in periodicals archive ?
Tokfrey et al [9] believe that the fact that the natural levels of lipoproteins stay the same is due to the daily body activities in adults and children.
The liver and intestine secrete apoAi that may initiate particle formation, which may also result from lipolysis of TG-rich lipoproteins [4] when apoAi and the relative excess of phospholipids pinch off from the lipoprotein.
Total cholesterol, total triglycerides, and cholesterol distribution among lipoproteins as predictors of atherosclerosis in selected lines of Japanese quail.
Like the Copenhagen City Heart Study, the Very Large Database of Lipids will provide a fruitful platform for investigation of lipoproteins and mortality, with the latter database having the distinctive advantage of directly measured remnant lipoprotein cholesterol (9).
Non-HDL is a novel idea that is an estimate of cholesterol content in the atherogenic lipoproteins, including intermediate-density lipoprotein (IDL), very low density lipoprotein (VLDL), LDL, and lipoprotein cholesterol Lp(a).
HOUSTON, April 28, 2011 /PRNewswire/ -- SpectraCell Laboratories has officially been granted a license to provide its Lipoprotein Particle Profile(TM) (LPP(TM)) test, which assesses cardiovascular risk, to New York state physicians and patients.
Plasma TAG consisted of TAG from portomicrons, VLDL, low density lipoprotein (LDL) and high density lipoprotein (HDL).
Since postprandial lipoproteins are derived from triglycerides, high levels of fasting triglycerides strongly suggest the presence of postprandial lipoproteins.
Apoproteins AI - V are found predominantly on high-density lipoproteins (HDL) where they serve structural roles and also activate the enzyme lecithin:cholesterol acyltransferase (LCAT) that esterifies cholesterol on HDL.
Our data suggest that this novel ion mobility-based method offers advantages over other procedures for lipoprotein particle analysis because it both measures particle size accurately on the basis of physical principles as well as directly counts the particles present at each size independently of particle composition.
The various sub-fractions are known as chylomicrons, very low-density lipoproteins (VLDL), low-density lipoproteins (LDL), high-density lipoproteins (HDL).
Primary care providers now have another option for assessing abnormal lipoprotein levels in adolescents--one that considers variations based on gender and natural fluctuations with age.