Studiies show that 60% to 70% of the proteins in HDL are made up of Apolipoprotein A-1. Apo A-1 turns on LCAT, which helps move cholesterol from tissues throughout the body to the liver, where it is broken down. Low serum HDL cholesterol levels have been linked to an increased risk of coronary artery disease (CAD). However, Apo A-1 may be a better indicator of CAD than HDL, especially in females.
The Apo A-1 level can also be used to help find out if someone has Tangier disease, which is the absence of alpha-lipoprotein.
Apolipoproteins such as high-density lipoprotein (HDL) and low-density lipoprotein (LDL) are made up of apolipoproteins. Lipoproteins bind fats and cholesterol and transport them throughout the body.
Apolipoprotein B (Apo B) is the structural backbone of three important lipoproteins:
- VLDL (very low-density lipoprotein) (VLDL)
- Lipoprotein of intermediate density (IDL)
- LDL (low-density lipoprotein) (LDL)
Apolipoprotein B aids LDL in binding to cell receptors and delivering cholesterol. It is also required for liver cells to bind and remove LDL from the blood .
Each VLDL, IDL, and LDL molecule contains exactly one molecule of Apo B. As a result, Apo B is a marker of “bad” cholesterol-carrying lipoprotein. ApoB-containing lipoproteins are the primary cause of artery hardening (atherosclerosis) and heart disease.
According to research, ApoB may aid in the defense of the body against harmful bacteria such as Staphylococcus aureus by interfering with a process known as quorum sensing. Quorum sensing is the process by which bacteria “talk” to each other in order to coordinate the actions required for survival .
ApoB testing is not routine, but if you have a family history of heart disease or other heart disease risk factors, your doctor may use ApoB to help determine your risk of heart disease (i.e. high cholesterol and triglycerides). It is also used to identify genetic diseases that result in abnormally low or high ApoB levels.
Low Apo B levels are commonly associated with liver disease, hepatitis B, malnutrition, hyperthyroidism, increased infection risk, impacts from medication, and genetic disorders.
High Apo B levels are associated with higher levels of “bad” cholesterol (LDL and VLDL cholesterol) and a higher risk of heart disease, diabetes, obesity, hypothyroidism, kidney disease, pregnancy, menopause, sleep disorders, growth hormone deficiency, and impacts from medication.
This test measures both proteins and provides a ratio to better analyze the balance in your body.