Lipoproteins, differentiated on the basis of density, size, and protein content, are essential for the biogenesis of plasma membrane and maintenance of its integrity; they also serve as sources of energy, hormone precursors, and signaling molecules.3 In blood, lipoproteins transport cholesterol and triglycerides. Abnormalities of lipoprotein metabolism appear to be the result of genetic factors, which modify the sensitivity of individuals to adverse dietary habits and to sedentary lifestyles.
Elevated cholesterol-rich low-density lipoproteins (LDLs) and lipoproteins that are rich in triglycerides (TGs), and decreased levels of high-density lipoproteins (HDLs) are strongly associated with atherosclerosis.3 Diet and exercise can reduce total plasma cholesterol concentrations by as much as 25%. If this approach is insufficient to normalize lipid levels drug therapy is initiated. Drugs in the top 300 that regulate lipoprotein metabolism (Table 1) fall into six major classes.2,3,10
| Drugs | Mechanisms of Action | Common Indications |
|---|---|---|
Inhibitors of cholesterol synthesis
|
Inhibit HMG-CoA reductase, the rate-limiting enzyme in cholesterol synthesis
|
|
Inhibitors of bile acid absorption
|
Bind to bile acids and prevent enterohepatic circulation
|
|
Inhibitors of cholesterol absorption
|
Decrease cholesterol transport into enterocytes
|
|
Fibrates
|
Agonists of peroxisome proliferator-activated receptor α (PPARα) in hepatocytes
|
|
Niacin
|
Reduces free fatty acid release from adipose tissue
|
|
Omega-3 fatty acids
|
Regulate hepatic nuclear transcription factors to reduce TG synthesis and increase fatty acid oxidation
|
|
