Cholesterol is made in the liver. It is an important part of cell membranes and also is a building block for steroid hormones and bile acids. The body needs cholesterol. However, in excessive concentrations in the blood, cholesterol can be deadly. It accumulates in the arteries which can lead to coronary heart diseases ending in heart attacks and strokes.
Fortunately, a normally functioning human system has a mechanism where cholesterol levels are kept in balance. The body has a system where cholesterol is biosynthesized, utilized, transported and excreted. Cholesterol is transported along with other molecules in a sphere shaped molecule called a lipoprotein.
Understanding the Different Lipoproteins
There are five different types of lipoproteins:
- Chylomicrons
- Very Low Density Lipoproteins
- Low Density Lipoproteins
- High Density Lipoproteins
Low Density Lipoproteins (LDLs) are the main carrier or cholesterol hence their name “bad” cholesterol. Elevated LDLs are usually indicative of potential problem. They interact with free radicals to form a new molecule which interacts with white blood cells to form plaque. Plaque buildup leads to blood flow restriction. This eventually leads to cardiovascular diseases and strokes.
Patients with elevated levels of LDL are encouraged to strategize ways to lower their cholesterol levels. Strategies include lifestyle and diet changes or medications in combination with the changes. Statins are a class of medications that are usually prescribed are can lower cholesterol levels by up to 60 percent.
Statins Affecting Cholesterol Synthesis
Cholesterol is synthesized in the liver. The process starts with acetate and proceeds through a series of steps. One of the main steps in the synthesis is catalyzed by the enzyme 3-hydroxy-3-methyl coenzyme A (HMG-CoA) reductase. By inhibiting the HMG-CoA reductase, pharmacologist determined that it is possible to control the biosynthesis of cholesterol. Statins work at this phase in the biosynthesis of statins.
Statins Side Effects
One of the drawbacks of pharmacology is the occasional lack of foresight which overlooks other possible enzyme target sites that may be affected by an artificially engineered inhibitor and its metabolites. As a result, statins and their metabolites have been associated with changes in muscle that lead to pain, weakness, and muscle inflammation.
The exact mechanism on how the muscles are affected is unknown but the adverse effects are more noticeable when statins are taken in combination with certain medications such as fibrates. It has been theorized that the muscle pain relates to the depletion of certain metabolites that are essential in the cell. This depletion can lead to an unstable cell wall which in turn causes the cell wall to breakdown and leak its contents in the muscles. Myalgia is one of the most common side effects associated with statin use. Other side effects include rhabdomyolysis and myositis.
Sources
Citkowitz, Elena. "Hypercholesterolemia, Polygenic: EMedicine Endocrinology." EMedicine - Medical Reference. 28 June 2010. Web. 29 June 2010.
