rasvaproteiineja

Rasvaproteiineja, also known as lipoproteins, are complex molecules found in the blood that transport fats, cholesterol, and other lipids throughout the body. They are composed of a core of hydrophobic lipids, such as triglycerides and cholesterol esters, surrounded by a shell of amphipathic phospholipids and unesterified cholesterol, with apolipoproteins embedded within. These apolipoproteins play a crucial role in lipoprotein structure, stability, and their interaction with cellular receptors, which facilitates lipid uptake and metabolism.

Lipoproteins are classified into different types based on their density, size, and the proportion of lipids and proteins they contain. The main classes include chylomicrons, very-low-density lipoproteins (VLDL), intermediate-density lipoproteins (IDL), low-density lipoproteins (LDL), and high-density lipoproteins (HDL). Chylomicrons are the largest and least dense, primarily transporting dietary fats from the intestines to other tissues. VLDL particles are synthesized in the liver and carry endogenous triglycerides to peripheral tissues. As triglycerides are removed, VLDL is converted into IDL and then LDL. LDL, often referred to as "bad cholesterol," delivers cholesterol to cells. HDL, or "good cholesterol," is produced in the liver and intestines and plays a role in reverse cholesterol transport, removing excess cholesterol from tissues and returning it to the liver for excretion.

The balance of different lipoprotein levels in the blood is critical for cardiovascular health. High levels of LDL cholesterol are associated with an increased risk of atherosclerosis, a condition where plaque builds up in arteries, potentially leading to heart disease and stroke. Conversely, higher levels of HDL cholesterol are generally considered protective against heart disease. Blood tests measuring various lipoprotein fractions are commonly used to assess cardiovascular risk and guide treatment strategies.