Lack of cholesterol-lowering efficacy of Cuban sugar cane policosanols in hypercholesterolemic persons

Consumption of policosanol enhances HDL functionality via CETP inhibition and reduces blood pressure and visceral fat in young and middle-aged subjects

It is well-known that policosanol can improve serum lipid profiles, although the physiological mechanism is still unknown. Here, we investigated functional and structural changes in lipoproteins after consumption of policosanol. To investigate the physiological effect of policosanol, we analyzed serum parameters in young non-smoker (YN; n=7, 24.0±2.4 years), young smoker (YS; n=7, 26.3±1.5 years), and middle-aged subjects (MN; n=11, 52.5±9.8 years) who consumed policosanol daily (10 mg/day) for 8 weeks. After 8 weeks, systolic blood pressure was significantly lowered to 4% (7 mmHg, p=0.022) from initial levels in the YS and MN groups. Moisture content of facial skin increased up to 38 and 18% from initial levels in the YS and MN groups, respectively. Serum triglyceride (TG) levels decreased to 28 and 26% from initial levels in the YN and MN groups, respectively. The percentage of high-density lipoprotein-cholesterol (HDL-C) in total cholesterol was elevated in all subjects (YN, 36%; YS, 35%; MN, 8%) after 8 weeks of policosanol consumption. All groups showed a reduction in serum glucose and uric acid levels. Serum cholesteryl ester transfer protein (CETP) activity was significantly diminished up to 21 and 32% from initial levels in the YN and MN groups, respectively. After 8 weeks, oxidation of the low-density lipoprotein fraction was markedly reduced accompanied by decreased apolipoprotein B (apoB) fragmentation. In the HDL fraction, paraoxonase activity was elevated by 17% along with elevation of apoA-I and cholesterol contents. Electron microscopy revealed that the size and number of HDL particles increased after 8 weeks, and the YS group showed a 2-fold increase in particle size. Daily consumption of policosanol for 8 weeks resulted in lowered blood pressure, reduced serum TG level and CETP activity, and elevated HDL-C contents. These functional enhancements of HDL can prevent and/or attenuate aging-related diseases, hypertension, diabetes and coronary heart disease.

Effects of high molecular weight alcohols from sugar cane fed alone or in combination with plant sterols on lipid profile and antioxidant status of Wistar rats

The effect of feeding a mixture of high molecular weight alcohols derived from sugarcane (SCA), both alone and in combination with phytosterols (PS), on changes in plasma lipids, organ cholesterol accumulation, and antioxidant status of Wistar rats was undertaken. Three separate experiments were conducted and each experiment had 3 subsets. In experiment 1, rats were fed on an AIN-76, semi-synthetic diet supplemented with 0%, 0.5%, and 5% SCA w/w. The second experiment consisted of feeding rats an atherogenic diet (AIN-76+0.5% cholesterol) containing 0%, 0.5%, and 5% SCA w/w. The third experiment consisted of feeding rats an atherogenic diet that contained 2% PS in combination with 0%, 0.5%, and 5% SCA. Rats fed the atherogenic diet exhibited significant elevations in total and low-density lipoprotein cholesterol, and significant reductions in the high-density lipoprotein/total cholesterol ratio, regardless of the presence of 0.5% or 5% SCA mixture. Serum cholesterol increased 29% to 35% in these animals compared with animals fed the nonatherogenic diets. In contrast, animals fed atherogenic diets that contained 2% PS exhibited no difference in serum lipids compared with counterparts fed nonatherogenic diets. The combined presence of SCA with PS had no effect on further lowering plasma cholesterol. No changes in C-reactive protein were observed, but plasma oxygen radical scavenging capacity values significantly (p < 0.05) decreased when rats were fed the atherogenic diets that contained the combination of PS and SCA. This result corresponded to an apparent greater (p < 0.05) susceptibility of red blood cells to oxidative stress.

Alternative prevention and treatment of cardiovascular disease, part 2

This article discusses alternative therapies for secondary prevention and treatment of major cardiac disorders: congestive heart failure, hypertension, dyslipidemias, and peripheral vascular disease. The role of various therapies (eg, herbal and botanic preparations, supplements, mind/body interventions, other alternative modalities of care) are addressed relative to each disease state and will hopefully give the practitioner or student a readily accessible suite of integrative therapies for common cardiac illnesses.

Policosanols as nutraceuticals: fact or fiction

Policosanols (PC) are very long chain aliphatic alcohols derived from the wax constituent of plants. In the early 1990s, researchers at Dalmer Laboratories in La Habana Cuba isolated and produced the first PC supplement from sugarcane wax. The original PC supplement has been approved as a cholesterol-lowering drug in over 25 countries throughout the Caribbean and South America. Cuban studies claim that 1 to 20 mg/day of the original PC supplement are effective at producing significant reductions in total cholesterol (TC) and low density lipoprotein cholesterol (LDL-C). These studies also show that PC supplements are potent antioxidants, promote proper arterial endothelial cell function, inhibit platelet aggregation and thrombosis, and serve as effective treatments for intermittent claudication. However, for the most part, those studies reporting therapeutic efficacy of PC were carried out by one research group situated in Cuba. Conversely, research groups outside of Cuba have failed to validate the cholesterol-lowering and antioxidant efficacy of PC. Cuban researchers, however, continue to claim that the efficacy is attributed to the unique purity and composition of the original PC preparation, a mixture not found in PC products used by external research groups. The absence of independent and external studies confirming the therapeutic benefits of PC in disease prevention and treatment raises questions regarding their true efficacy.

Effect of sugar cane policosanol on lipid profile in primary hypercholesterolemia

Policosanol, a mixture of long-chain aliphatic primary alcohols, is used as a cholesterol-lowering supplement. The effectiveness of policosanol is still questionable. To determine the lipoprotein-lowering effects of Cuban sugar cane-derived policosanol a double-blind, randomized, placebo controlled trial was performed. Sixty-eight primary hypercholesterolemic subjects were enrolled and randomly assigned to the treatment or to the control group. The first group received sugar cane policosanol 20 mg daily for 8 weeks, while the control group was treated with placebo. All subjects followed a normocaloric diet. The content of policosanol in the supplement tablets was assessed by gas chromatography. A total of 32 subjects in the policosanol group and 31 subjects in the control group completed the study. Body mass index, total cholesterol, HDL-cholesterol, LDL-cholesterol and triglyceride plasma levels did not change significantly in either group. In conclusion, sugar cane policosanol at doses of 20 mg daily showed no lipid lowering effects in subjects with primary hypercholesterolemia.

Cholesterol-lowering nutraceuticals and functional foods

Epidemiological studies have demonstrated that elevated levels of plasma total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) are the major risk factors for coronary heart disease (CHD), whereas high concentrations of plasma high-density lipoprotein cholesterol (HDL-C) and a low ratio of TC to HDL-C are protective against CHD. A relationship between plasma TC and the risk of CHD is well established at concentrations above 240 mg/dL. In addition to the use of three main classes of cholesterol-lowering medications, including HMG-CoA reductase inhibitors, anion-exchange resins, and fibrates, a nutritionally balanced diet that reduces saturated fat and cholesterol intake has traditionally been the first goal of dietary therapy in lowering plasma TC. In recent years, nutraceuticals and functional foods have attracted much interest as possible alternative therapies for lowering plasma TC, especially for hypercholesterolemia patients, whose blood cholesterol level is marginally high (200-240 mg/dL) but not high enough to warrant the prescription of cholesterol-lowering medications. This review summarizes the findings of recent studies on the production, application, efficacy, and mechanisms of popular cholesterol-lowering nutraceuticals and functional foods.

Changes in cholesterol kinetics following sugar cane policosanol supplementation: a randomized control trial

Background

Sugar cane policosanols (SCP) have been shown to exert cholesterol-modulating properties in various studies conducted in Cuba by substantially reducing cholesterol synthesis. Independent research examining changes in cholesterol kinetics in response to SCP is limited to few studies, none of which was able to replicate findings of the original research. Moreover, no data are available on the effect of SCP on cholesterol absorption to date. The present study was undertaken to determine effects on cholesterol kinetics, namely synthesis and absorption, within hypercholesterolemic individuals consuming a SCP treatment. Twenty-one otherwise healthy hypercholesterolemic subjects participated in a randomized double-blind crossover study where they received 10 mg/day of policosanols or a placebo incorporated in margarine as an evening snack for a period of 28 days. The last week of the study phase, subjects were given ¹³C labelled cholesterol and deuterated water for the measurement of cholesterol absorption and synthesis respectively. Blood was collected on the first two and last five days of the trial. Cholesterol absorption and synthesis were determined by measuring red cell cholesterol ¹³C and deuterium enrichment, respectively.

Results

There was no significant change in LDL cholesterol levels as compared to control. In addition, the area under the curve for red cell cholesterol ¹³C enrichment across 96 hours was not significantly different in the SCP group as compared to control. Similarly, no difference was observed in the fractional rate of cholesterol synthesis over the period of 24 hours between the two treatment groups.

Conclusion

The findings of the present study fail to support previous research concerning efficacy and mechanism of action for policosanols.

Effects of emulsified policosanols with different chain lengths on cholesterol metabolism in heterozygous LDL receptor-deficient mice

Policosanol is a mixture of long-chain primary aliphatic saturated alcohols. Previous studies in humans and animals have shown that these compounds improved lipoprotein profiles. However, more-recent placebo-controlled studies could not confirm these promising effects. Octacosanol (C28), the main component of sugarcane-derived policosanol, is assumed to be the bioactive component. This has, however, never been tested in an in vivo study that compared individual policosanol components side by side. Here we present that neither the individual policosanol components (C24, C26, C28, or C30) nor the natural policosanol mixture (all 30 mg/100 g diet) lowered serum cholesterol concentrations in LDL receptor knock-out (LDLr(+/-)) mice. Moreover, there was no effect on gene expression profiles of LDLr, ABCA1, HMG-CoA synthase 1, and apolipoprotein A-I (apoA-I) in hepatic and small intestinal tissue of female LDLr(+/-) mice after the 7 week intervention period. Finally, none of the individual policosanols or their respective long-chain fatty acids or aldehydes affected de novo apoA-I protein production in vitro in HepG2 and CaCo-2 cells. Therefore, we conclude that the evaluated individual policosanols, as well as the natural policosanol mixture, have no potential for reducing coronary heart disease risk through effects on serum lipoprotein concentrations.

Increasing apoA-I production as a target for CHD risk reduction

Dyslipidemia leading to coronary heart diseases (CHD) enables venues to prevent or treat CHD by other strategies than only lowering serum LDL cholesterol (LDL-C) concentrations, which is currently the most frequently targeted change. Unlike LDL-C, elevated high-density lipoprotein cholesterol (HDL-C) concentrations may protect against the development of CHD as demonstrated in numerous large-scale epidemiological studies. In this review we describe that besides elevating serum HDL-C concentrations by increasing alpha-HDL particles, approaches to elevate HDL-C concentrations by increasing pre-beta HDL particle concentrations seems more attractive. Besides infusion of apoA-I(Milano), using apoA-I mimetics, or delipidation of alpha-HDL particles, elevating de novo apoA-I production may be a suitable target to functionally increase pre-beta HDL particle concentrations. Therefore, a detailed description of the molecular pathways underlying apoA-I synthesis and secretion, completed with an overview of known effects of pharmacological and nutritional compounds on apoA-I synthesis will be presented. This knowledge may ultimately be applied in developing dietary intervention strategies to elevate apoA-I production and serum HDL-C concentrations and consequently lower CHD risk.

Lack of effect of sugar cane policosanol on plasma cholesterol in Golden Syrian hamsters

Policosanol is a mixture of higher aliphatic alcohols shown to have beneficial effects on plasma lipid levels in animals and humans. Over 50 studies have reported significant reductions in plasma cholesterol using policosanol obtained from Cuban sugar cane (Dalmer, La Havana, Cuba). However, other research groups using policosanol from alternative sources have failed to reproduce the efficacy of these alcohols observed in earlier studies. Therefore, the objective of the present study was to compare the cholesterol-lowering effect of the Dalmer sugar cane policosanol (SCP) product versus an alternative mixture of similar policosanol composition. Forty-eight male Golden Syrian hamsters were randomly assigned to four groups and fed experimental diets ad libitum for a period of 4 weeks: (i) non-cholesterol control, (ii) 0.1% cholesterol control, (iii) 0.1% cholesterol diet supplemented with 275 mg/kg diet of Dalmer Cuban sugar cane policosanol and (iv) 0.1% cholesterol diet supplemented with 275 mg/kg diet of alternative sugar cane policosanol. Hamsters were sacrificed and blood was collected at the end of the feeding period. Body weights and food intakes were similar across study groups. Neither of the two policosanol treatments had any significant effect on plasma lipid levels, as compared to cholesterol control. The outcome of the present study questions the clinical usefulness of policosanol mixtures as cholesterol-lowering nutraceuticals.