Low-dosage statins reduce choroidal damage in hypercholesterolemic rabbits

Area of Science:

• Ophthalmology
• Cardiovascular Research
• Pharmacology

Background:

• Long-term hypercholesterolemia can lead to lipid accumulation in the choroid, potentially impairing vascular function.
• The pleiotropic effects of statins beyond lipid-lowering are of interest for vascular health.

Purpose of the Study:

• To investigate ultrastructural changes in the choroid of hypercholesterolemic rabbits following low-dose statin therapy.
• To assess the impact of statins on endothelial cells (EC) and vascular smooth-muscle cells (VSMC) morphology and function.

Main Methods:

• New Zealand rabbits were fed a cholesterol-enriched diet for 8 months.
• One group received low-dose fluvastatin or pravastatin sodium.
• Eyes were examined using transmission-electron microscopy.

Main Results:

• Hypercholesterolemic rabbits showed significant lipid buildup and vascular compression in the choroid.
• Statin treatment markedly reduced suprachoroidal foam cells and vascular lipids.
• Statin-treated animals exhibited preserved ultrastructural features of EC and VSMC, unlike necrotic changes in untreated rabbits.
• Bruch's membrane showed reduced lipids and increased collagen after statin treatment.

Conclusions:

• Low-dose statins effectively reduced choroidal lipid deposition and macrophage infiltration.
• Statin therapy normalized vascular lumens in choroidal vessels, independent of cholesterol reduction.
• Preserved ultrastructural integrity of choroidal EC and VSMC suggests improved endothelial function and reduced ischemia.