What is the mechanism of action of statins in lipid-lowering therapy?

The correct answer is the inhibition of HMG-CoA reductase, which is the primary mechanism of action of statins. Statins are a class of lipid-lowering medications that work by blocking the enzyme HMG-CoA reductase in the liver. This enzyme plays a crucial role in the biosynthesis of cholesterol; it is responsible for converting HMG-CoA to mevalonate, which is a precursor in cholesterol production. By inhibiting this enzyme, statins effectively lower the levels of cholesterol produced by the liver, leading to a decrease in circulating low-density lipoprotein (LDL) cholesterol.

This reduction in LDL is significant in managing hyperlipidemia and preventing cardiovascular diseases. Statins also have additional beneficial effects, such as improving endothelial function, stabilizing atherosclerotic plaques, and reducing inflammation within blood vessels.

The other options represent different mechanisms associated with other types of lipid-lowering agents or functions. For example, the inhibition of cholesterol absorption in the intestines is characteristic of drugs such as ezetimibe. Activation of PPAR receptors is linked to fibrates, which primarily target triglyceride levels. Increasing lipoprotein lipase activity is again a mechanism more relevant to fibrates, which help decrease triglycerides and