The effect of policosanol, a mixture of high-molecular-weight aliphatic alcohols isolated from sugarcane wax, on casein-induced hypercholesterolaemia in rabbits was studied. When policosanol was administered by the oral route once daily for 30 d (50mgkg) the increases in plasma total cholesterol and LDL-cholesterol (LDC-C) were significantly reduced when compared with the control group. The incorporation of 3 H~0 into sterols in the liver was significantly depressed, suggesting inhibition of hepatic cholesterol biosynthesis. The oral administration of policosanol raised the rate of removal of '251-labelled LDL from serum. Kinetic parameters calculated following injection of ['qLDL showed than in casein-fed rabbits, the terminal half-life (th) was signi6cantly decreased after policosanol treatment. The hepatic LDL-binding activity was increased after policosanol administration which suggested that the enhanced clearance was due, at least in part, to increased receptor-mediated uptake of LDL by the liver. Considered together, these results suggest that policosanol can significantly reduce the increase of plasma LDL-C in rabbits fed on a wheat starch-casein diet by reducing cholesterol biosynthesis in the liver. Such an effect could account for the enhancement of LDL catabolism through the receptor-mediated pathway.Policosanol: Hypercholesterolaemia: Cholesterol biosynthesis: LDL Policosanol is a mixture of high-molecular-mass aliphatic alchohols isolated and purified from sugar cane (Saccharum oficinarum L.) wax. Octacosanol (M, 410.7) is its major component, followed by triacontanol (M, 438.5) and hexacosanol (MI 382.4) while other alcohols (tetracosanol, heptacosanol, nonacosanol, dotriacontanol and tetratriacontanol)

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Administration of D-004 resulted in marked and significant prevention of phenylephrine-induced impairment of micturition and histological changes in rat prostate. These findings indicate that, in vivo, D-004 effectively opposes these responses to phenylephrine, which are mediated through urogenital alpha(1)-adrenoceptors. In this respect, D-004 was moderately more effective than Saw palmetto, a phytotherapeutic standard used to treat BPH, but less effective than tamsulosin, a selective alpha(1A)-adrenoceptor antagonist.

1. The present study was undertaken to compare the effects of a higher dose of policosanol, a cholesterol-lowering drug, (40 mg/day) with the effects of 20 mg/day policosanol on platelet aggregation in healthy volunteers and type II hypercholesterolaemic patients. 2. Study subjects were randomized to receive, under double-blind conditions, placebo or policosanol (20 or 40 mg/day) for 30 days once a day. Blood sampling was performed at baseline and after 30 days on therapy. 3. Platelet aggregation was induced with three aggregating agents: arachidonic acid (AA), collagen and low doses of ADP. 4. Policosanol (20 and 40 mg/day) moderately yet significantly reduced platelet aggregation, but no differences were observed in the effects produced by either dose of policosanol. In healthy volunteers, policosanol at 20 and 40 mg/day inhibited aggregation induced by 2 mmol/L AA (28.2 and 24.9%, respectively), 1 micro g/mL collagen (21.1 and 20.2%) and 1 micro mol/L ADP (30.9 and 29.1%). Changes that occurred following the administration of placebo were not significant, although an upward trend for collagen- and ADP-induced aggregation occurred in normal and hypercholesterolaemic subjects, respectively, thus partially masking the effects of policosanol on these responses. 5. The antiplatelet effects of policosanol at 20 and 40 mg/day in hypercholesterolaemic patients were also similar, so that both doses inhibited aggregation induced by 1.5 mmol/L AA (20.1 and 33.0%, respectively), 0.5 micro g/mL collagen (22.7 and 21.1%) and 1 micro mol/L ADP (40.5 and 34.7%). 6. In addition, after 30 days of therapy, 20 and 40 mg/day policosanol significantly (P < 0.01) reduced low-density lipoprotein-cholesterol (15.9 and 17.0%, respectively) and total cholesterol (12.4 and 12.3%, respectively; P < 0.05), yet increased high-density lipoprotein-cholesterol values by 5% in both groups (P < 0.05). 7. Triglycerides were decreased compared with baseline, but not with respect to the placebo. 8. We conclude that the antiplatelet effects induced by 40 mg/day policosanol administered for 30 days to healthy volunteers and to hypercholesterolaemic patients were similar to the effects induced by 20 mg/day policosanol. Thus, no enhancement of the response was achieved with the use of a higher dose of policosanol in study patients.

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