Effect of niacin monotherapy on high density lipoprotein composition and function

Area of Science:

• Cardiovascular Science
• Lipid Metabolism
• Proteomics

Background:

• Niacin favorably affects plasma lipids, increasing HDL-C and lowering triglycerides.
• Cardiovascular outcome trials of niacin have yielded inconsistent results.
• The HDL proteome may better reflect HDL's cardioprotective function than HDL-C levels.

Purpose of the Study:

• To evaluate the impact of niacin monotherapy on HDL protein composition and function.
• To analyze changes in the HDL proteome in response to niacin treatment.

Main Methods:

• A 20-week study involving 11 participants receiving extended-release niacin.
• HDL was isolated at baseline, week 16, and week 20.
• HDL proteome analysis using mass spectrometry and label-free quantification.

Main Results:

• Niacin increased HDL-C by 16% and decreased LDL-C by 20%.
• Niacin significantly altered 5 HDL proteins, including a 3-fold increase in serum amyloid A (SAA).
• Cholesterol efflux capacity and endothelial function were not significantly impacted by niacin during treatment.

Conclusions:

• Extended-release niacin monotherapy increases HDL-associated SAA.
• SAA is an acute phase protein linked to impaired HDL function.
• Niacin's effects on HDL protein composition may explain mixed clinical trial outcomes.