Apolipoprotein B Test

Apolipoprotein B Profile test measures the condition of high cholesterol and cardiovascular diseases. It also helps diagnose a very rare inherited deficiency of Apolipoprotein B. Apo B is a structural apolipoprotein of LDL particles that facilitates their transportation to the peripheral tissues. It is also the main protein constituent of lipoproteins like Very Low-Density Lipoprotein (VLDL) and Low-Density Lipoprotein (LDL). LDL is actually bad cholesterol. Hence, the Apolipoprotein B test measures the amount of Apo B in the bloodstream. Most lipoproteins are triglyceride and cholesterol-rich, which carry the lipids through the body for the usage of the cell. Lipids are not soluble with water and thus, they have to combine with Apolipoproteins to travel in the bloodstream. Apolipoproteins are also good at providing structural integrity to the lipoproteins by protecting them from the water-repellent hydrophobic lipids at their centre. Lipoprotein particles known as Chylomicrons carry the dietary lipids from the digestive tract through the bloodstream to the tissue, mainly the liver. The liver then repackages these dietary lipids and combines them with Apo B-100 to form triglyceride-rich VLDL. This combination is like a cab full of passengers with Apo B-100 as the cab driver. In the bloodstream, the cab moves from one place to another while releasing one passenger at a time. Lipoprotein Lipase is an enzyme responsible for removing triglycerides from VLDL to produce intermediate-density lipoproteins and LDL. Each VLDL particle consists of one molecule of Apo B. This is retained as VLDL, which loses the triglycerides and shrinks to become a cholesterol-rich LDL. Apo B is recognised by the receptors found on the surface of the body's cells. These receptors have the responsibility of promoting the uptake of cholesterol into the cells. The cholesterol that Apo B-100 and LDL transports are important for cell membrane integrity, steroid production and sex hormone production. However, if the amount of LDL exceeds in the body, it can lead to fatty deposits in artery walls with hardening and scarring of the blood vessels. The fatty depositions narrow the blood vessels and this increases the chances of a heart attack. Apo B-100 levels are almost directly proportional to LDL-C levels. However, medical experts feel that the results of Apolipoprotein B test are a better indicator of the risk of cardiovascular disease compared to LDL-C. Apolipoprotein B test is usually included in the complete Lipid profile test. The doctor will usually ask you to take the test if you have a family history of heart diseases and high cholesterol with triglycerides. It also helps in understanding the cause of abnormal lipid levels when someone has high triglyceride levels. Apolipoprotein B Test is prescribed to monitor the effectiveness of the lipid treatment as well. In some cases, the Apo B test helps diagnose a genetic problem that causes over or underproduction of Apo B. High cholesterol and triglycerides are common health conditions in India. People from urban and rural areas both have this problem because of hectic and unhealthy lifestyles. The urban population has developed this issue because of stress and poor sleep cycle as well. Poor nutrition also adds to these problems.