Statins are potent inhibitors of cholesterol biosynthesis and have been used for the reduction of serum cholesterol levels to prevent cardiovascular diseases according to the cholesterol hypothesis of atherosclerosis. However, a wide varieties of beneficial effects of statins are known to rather actually occur earlier than serum cholesterol goes down, indicating cholesterol-independent effects. The effects beyond cholesterol lowering are socalled "pleiotropic effects" of statins, including eNOS expression, anti-oxidative function, anti-inflammatory action, osteomorphogenesis and so on. In addition to those, the effects of statins against carcinogenesis and degenerative processes in the brain leading to Alzheimer's disease and Parkinson's disease are examined in the literature.
The pleiotropic effects of statins observed so far might be the reverse of a coin, where serious impairments of physiological functions of the intermediates of cholesterol biosynthesis take place. Adverse effects may happen to be manifested in the course of long-term use of statins. Considering the not much size of the benefits, statins should not be given to a large population to avoid terrible side-effects or demerits. Statin use may rather be better to be confined to patients with familial hypercholesterolemia who definitely obtain merits.
