Policosanol is a
cholesterol-lowering
drug isolated from
sugar cane wax with concomitant antiplatelet effects that prevents
lipofundin-induced atherosclerotic lesions in rabbits and rats, including foam cell formation, and also reduces foam cell formation in
carrageenan-induced
granulomas in rats, while it inhibits proliferation of smooth muscle cells induced in rabbit cuffed artery. This study was undertaken to determine whether
policosanol prevents endothelium damage and increase in arterial wall thickness in rabbits with arterial walls damaged with a
forceps. Artery
forceps were placed over the central artery of the right ear of all rabbits, and each artery was injured eight times. Animals were randomly distributed into four groups: a positive control group treated with
Tween 20/H2O vehicle, two groups treated with
policosanol (5 and 25 mg/kg, respectively), and a group treated with
aspirin (8 mg/kg). Treatments were given for 30 days. Damaged arteries were examined by light and electron (transmission and scanning) microscopy. To evaluate intimal thickening, areas of intima were measured, and a significant reduction in
policosanol-treated animals was observed. The endothelial surface, studied with scanning electron microscopy, revealed several types of damage. In control group, the endothelial surface was severely damaged. De-endothelialized areas were reduced in
policosanol-treated animals. Platelet adhesion to subendothelium was seen in all animals of the control group, whereas
policosanol-treated groups exhibited significantly reduced platelet adhesion.
Policosanol also reduced, dose-dependently, the platelet sequestration induced in the damaged vessel wall, partially preventing the reduction in platelet count. It is concluded that
policosanol prevents endothelium injury and reduces significantly intimal thickness of rabbit arteries damaged with
forceps.