Page 117 - The Manga Guide to Biochemistry

What is arteriosclerosis?

Now that you have a better understanding of cholesterol, imagine what would
happen if the density of LDL (bad) in the blood increases while the density of HDL
(good) decreases.

Hmmm, I guess cholesterol would be transported into the body’s tissues faster than
it could be removed, and it would pile up in the blood vessels.

Right. Cholesterol will accumulate on the walls of blood vessels, the lumens of the
blood vessels will get narrower, and the flow of blood will be obstructed. This is called
arteriosclerosis.

Normal blood Cholesterol Immune cells are
vessel gets recruited, and the
lumen steadily gets
deposited.
narrower.

The blood vessels get thicker and harder, and as the symptoms advance, it can
lead to sickness or even death.

Cholesterol can lead to death?! Not to be taken lightly, I guess...

Let’s look at a typical type of arteriosclerosis called atherosclerosis. Scientists believe
the process goes something like this: First, LDL cholesterol is deposited on the inner
wall of a damaged blood vessel. This cholesterol is then eaten by phagocytes,* such
as macrophages, and bulging cells filled with fat, called foam cells, accumulate.

When this happens, the smooth muscle cells that create the walls of a blood
vessel also end up changing significantly, getting harder and thicker.

* A phagocyte is a gluttonous kind of white blood cell that eats just about anything. They’re an essential
part of the immune system.

Biochemistry in Our Everyday Lives 103