Question

Which of the following hyperlipidaemic drugs act via a GPCR?

• A. Nicotinic acid
• B. Fenofibrate
• C. Atorvastatin
• D. Ezetimibe

Answer 1

The Correct Option is A

The question asks which of the following hyperlipidaemic drugs acts via a GPCR (G-protein-coupled receptor). To answer this question, let's examine each option to determine its mechanism of action:

1. Nicotinic acid (Niacin):
   • Nicotinic acid acts as a lipid-lowering agent primarily by inhibiting the hepatic synthesis of VLDL, which in turn reduces LDL levels.
   • Niacin works through a G-protein-coupled receptor known as the GPR109A receptor. This receptor is found in adipose tissue and is responsible for the inhibition of lipolysis, thereby reducing free fatty acid availability and decreasing triglyceride synthesis.
2. Fenofibrate:
   • Fenofibrate primarily works by activating peroxisome proliferator-activated receptor alpha (PPAR-alpha), which is a nuclear receptor, not a GPCR.
3. Atorvastatin:
   • Atorvastatin is a statin that works by inhibiting HMG-CoA reductase, an enzyme critical for cholesterol synthesis. This mechanism does not involve GPCRs.
4. Ezetimibe:
   • Ezetimibe reduces blood cholesterol by inhibiting the absorption of cholesterol at the brush border of the small intestine. This action does not involve interaction with GPCRs.

From this analysis, it is clear that Nicotinic acid is the only drug in the list that acts via a GPCR, specifically the GPR109A receptor.

Therefore, the correct answer is Nicotinic acid.