With Hypertriglyceridemia, hyper means high, -emia refers to blood levels, and triglycerides are the most abundant fatty molecules in an organism.
So, hypertriglyceridemia is when there’s excess triglycerides in the blood.
Specifically, hypertriglyceridemia is when there are more than 150 mg of triglycerides per deciliter of blood.
Triglycerides can be deposited in subcutaneous tissue and around organs and function as energy storage in the body.
We can either get triglycerides from our diet, which are called exogenous triglycerides; or our liver can synthesize them from other molecules, in which case they’re called endogenous triglycerides.
Now, exogenous triglycerides are first absorbed in the small intestine, and then they undergo a series of changes in order to be transported and deposited in the body.
So, after triglycerides are absorbed, they enter the intestinal mucosal cells, inside of which they’re coupled with various apolipoproteins and phospholipids to create chylomicrons, which are one type of lipoprotein.
Lipoproteins are made up of lipids (like triglycerides or cholesterol) or phospholipids and proteins (like apolipoproteins CII, CIII, or E).
The main job of lipoproteins is to carry insoluble molecules, like triglycerides, from the intestines to the circulation.
That's because, normally, triglycerides are insoluble in liquid environments like blood.
Now, the newly created chylomicrons enter the bloodstream and bind to the wall of capillaries in adipose and skeletal muscle tissue.
At the binding site, they interact with the lipoprotein lipase enzyme leading to the breakdown of the triglyceride core and liberation of free fatty acids directly into the adipocytes or skeletal muscle cell, where they’re either stored or used for energy.
After triglycerides leave the chylomicron, what’s left is called a remnant chylomicron.
Remnant chylomicrons are high in cholesterol esters and they’re cleared from circulation by the liver when the apolipoprotein E binds to Apo-B100/E receptor on the hepatic cell membrane.