What mechanism of action do bile acid sequestrants have?

Bile acid sequestrants primarily work by binding to bile acids in the intestine. When bile acids are sequestered, they cannot be reabsorbed into the bloodstream. This prompts the liver to use more cholesterol to produce additional bile acids to replace those lost. As a result, the activity of the liver increases in terms of synthesizing cholesterol, which ultimately decreases serum cholesterol levels. This mechanism underscores how bile acid sequestrants contribute to lowering LDL cholesterol and improving lipid profiles.

The incorrect options reflect different mechanisms associated with other types of lipid-lowering agents or processes. For instance, inhibiting cholesterol absorption specifically targets the intestinal absorption of dietary cholesterol, while activating lipoprotein lipase is more relevant to triglyceride reduction in plasma. Alternatively, blocking the reabsorption of cholesterol from the gut does not accurately describe the primary action of bile acid sequestrants. Instead, their effect is on bile acids rather than directly blocking cholesterol alone.