Lipoprotein is a complex of lipids and apolipoproteins, the form in which lipids are transported in the blood.
Lipoproteins is not only for intravascular lipid transport 血管內脂質傳輸. It plays an important role in regulating important cell functions. From the time of their production to their catabolism 代謝, lipoproteins undergo a series of structural reorganizations due to enzymatic and physico-chemical processes, yielding products that can be described by models, obeying precise molecular volume and surface-area requirements.
Lipoprotein metabolism is regulated and controlled by the specific apolipoprotein (apo-) 載脂蛋白 constituents of the various lipoprotein classes. The major apolipoproteins include apoE, apoB, apoA-I, apoA-II, apoA-IV, apoC-I, apoC-II, and apoC-III.
Lipoproteins – The Actual Cause of Heart Disease
More than 50% of people with “normal cholesterol” still develop heart attacks. It is because Lipoproteins, not cholesterol, cause heart disease. Lipoproteins are the carriers transporting cholesterol through the blood. Some lipoproteins cause cholesterol penetrating the artery wall more easily and causing the artery to clog. These lipoprotein plaques become inflamed and rupture, causing a heart attack.
Lipoproteins consist of various types and sizes. Three types of lipoproteins carry cholesterol:
HDL (high density lipoproteins)
LDL (low density lipoproteins)
VLDL (very low density lipoproteins)
HDL particles are good cholesterol, or lipoprotein. They help cleaning up the artery wall, reversing the blockages and carrying cholesterol back to the liver. Then the liver deposits cholesterol into the bile, and it flushes out with the bowel movement. Large HDL particles are the cleaner of arteries. In the contrary if all of HDL particles are small, it is a sign that your artery cleaner is not working resulting in artery continues to build up plaque.
LDL particles transport cholesterol to human body cells which need cholesterol to make cell membrane. Cholesterol makes the cell waterproof because water is unable penetrating fat. If LDL particles are small, they penetrate the artery wall more readily, causing damaging plaque. If the LDL particles are large, they are unable penetrating artery wall. Therefore, no damaging plaque occurs. Also, the smaller the LDL particle, the more it needs to carry cholesterol.
More than 1300 LDL particles per liter of blood, increases heart attack and death rate. The “number” of LDL particles and “size” of LDL and HDL particles determine the risk of heart disease.
Measuring cholesterol as traditionally did (Total cholesterol, HDL cholesterol, LDL cholesterol) tells you almost nothing. It might be the routine, but it does not provide the correct indication of heart disease risk.
If you want to know the “real” cholesterol risk, measure the “right” thing – the blood test that tells you something else, not just your total cholesterol.