What do fibrates do?

What do fibrates do?

• A. Inhibit HMG-CoA reductase.
• B. Activate PPAR-alpha to increase lipid metabolism, lowering triglycerides and raising HDL.
• C. Block dihydrofolate reductase.
• D. Activate PPAR-gamma to increase adiponectin.

Answer: (B)

Fibrates act as agonists of PPAR-alpha, which ramps up genes involved in lipid catabolism and lipoprotein processing. When PPAR-alpha is activated, the liver increases fatty acid oxidation and upregulates lipoprotein lipase, promoting clearance of triglyceride-rich particles from the bloodstream. This leads to lower triglyceride levels and, often, a rise in HDL cholesterol, improving the lipid profile. The other mechanisms described belong to different drugs: inhibiting HMG-CoA reductase is how statins lower cholesterol synthesis; blocking dihydrofolate reductase is a mechanism of certain chemotherapy agents; activating PPAR-gamma to raise adiponectin is the action of thiazolidinediones, which mainly affect insulin sensitivity. So the best description of fibrates is that they activate PPAR-alpha to increase lipid metabolism, lowering triglycerides and raising HDL.

Fibrates act as agonists of PPAR-alpha, which ramps up genes involved in lipid catabolism and lipoprotein processing. When PPAR-alpha is activated, the liver increases fatty acid oxidation and upregulates lipoprotein lipase, promoting clearance of triglyceride-rich particles from the bloodstream. This leads to lower triglyceride levels and, often, a rise in HDL cholesterol, improving the lipid profile. The other mechanisms described belong to different drugs: inhibiting HMG-CoA reductase is how statins lower cholesterol synthesis; blocking dihydrofolate reductase is a mechanism of certain chemotherapy agents; activating PPAR-gamma to raise adiponectin is the action of thiazolidinediones, which mainly affect insulin sensitivity. So the best description of fibrates is that they activate PPAR-alpha to increase lipid metabolism, lowering triglycerides and raising HDL.