Plant stanols

Historically, the absorption of lipid-soluble nutrients has been considered to be carrier-independent, with solutes diffusing into enterocytes down concentration gradients. This is true for some lipid-soluble components of plants (e.g. the hydroxytyrosol in olive oil Manna et al., 2000). However, transporters have been reported for several lipid-soluble nutrients. For example, absorption of cholesterol is partly dependent on a carrier-mediated process that is inhibited by tea polyphenols (Dawson and Rudel, 1999) and other phytochemicals (Park et al., 2002). A portion of the decreased absorption caused by tea polyphenols may be due to precipitation of the cholesterol associated with micelles (Ikeda et al., 1992). Alternatively, plant stanols and other phytochemicals may compete with cholesterol for transporter sites (Plat and Mensink, 2002). It is likely that transporters for other lipid-soluble nutrients are also affected by phytochemicals, although this has not been adequately investigated. 

Therapeutic lifestyle changes should be the first approach tried in all patients (Table 9—7).3 An adequate trial of TLC should be employed in all patients, but pharmacotherapy should be instituted concurrently in higher-risk patients. This includes dietary restrictions of cholesterol and saturated fats as well as regular exercise and weight reduction. In addition, therapeutic options to enhance LDL cholesterol lowering such as consumption of plant stanols/sterols (which competitively inhibit incorporation of cholesterol into micelles) and dietary fiber should be encouraged. These therapeutic options collectively may reduce LDL cholesterol by 20% to 25%. 

Hallikainen MA, Sarkkinen ES and Uusitupa MIL 2000. Plant stanol esters affect serum cholesterol concentrations of hypercholesterolemic men and women in a dose-dependent manner. J Nutr 130 767-776. 

Hallikainen, M.A., Sarkkinen, E.S., Gylling, H., Erkkila, A.T., and Uusitupa, MX 2000. Comparison of the effects of plant sterol ester and plant stanol ester-enriched margarines in lowering serum cholesterol concentrations in hypercholesterolaemic subjects on a low-fat diet. Eur. J. Clin. Nutr. 54, 715-725. 

Nguyen, T.T. 1999. The cholesterol-lowering action of plant stanol esters. J. Nutr. 129, 2109-2112. Ni, W., Yoshida, S., Tsuda, Y., Nagao, K., Sato, M., and Imaizumi, K. 1999. Ethanol-extracted soy protein isolate results in elevation of serum cholesterol in exogenously hypercholesterolemic rats. Lipids 34, 713-716. 

Nissinen, M., Gylling, H., Vuoristo, M., and Miettinen, T.A. 2002. Micellar distribution of cholesterol and phytosterols after duodenal plant stanol ester infusion. Am. J. Physiol. Gastrointest. Liver Physiol. 282, G1009-G1015. 

O Neill, F.H., Sanders, T. A. B., and Thompson, G.R. 2005. Comparison of efficacy of plant stanol ester and sterol ester Short-term and longer-term studies. Am. J. Cardiol. 96(Suppl.), 29D-36D. Oakenfull, D.G. 1986. Aggregation of saponins and bile acids in aqueous solution. Aust. J. Chem. 39, 1671-1683. 

Note PC = placebo controlled PSE = plant sterol esters PSNE = plant stanol esters CO = cross-over RM = repeated measures SB = single blind. 

Food and Drug Administration, Talk Paper, FDA authorizes new coronary heart disease health claim for plant sterol and plant stanol esters, http // www.fdagov/bbs/topics/ANSWERS/ANS01033.html. Accessed June 7, 2002. 

Mensink, R.R et al.. Effects of plant stanol esters supplied in low-fat yogurt on serum lipids and lipoproteins, noncholesterol sterols and fat soluble antioxidant concentrations, Atherosclerosis, 160, 205, 2002. 

Temme, E.H. et al.. Effects of a plant sterol-enriched spread on serum lipids and lipoproteins in mildly hypercholesterolaemic subjects, Acta Cardiol, 57, 111, 2002. Plat, J. et al.. Effects on serum lipids, lipoproteins and fat soluble antioxidant concentrations of consumption frequency of margarines and shortenings enriched with plant stanol esters, Eur. J. Clin. Nutr., 54, 671, 2000. 

Gylling, H. and Miettinen, T.A., Cholesterol reduction by different plant stanol mixtures and with variable fat intake. Metabolism, 48, 575, 1999. 

Blair, S.N. et al.. Incremental reduction of serum total cholesterol and low-density lipoprotein cholesterol with the addition of plant stanol ester-containing spread to statin therapy. Am. J. Cardiol, 86, 46, 2000. 

Rlat, J. and Mensink, R.R., Effects of plant stanol esters on LDL receptor protein expression and on LDL receptor and HMG-CoA reductase mRNA expression in mononuclear blood cells of healthy men and women, EASES J., 16, 258, 2002. 

A typical Western diet contains approximately 100-300 mg and 20-50 mg of plant sterol and plant stanol, respectively. The relationship between total dietary phytosterol content and the fatty acid composition of the diet decreases with increasing saturated fatty acids, whereas the total dietary phytosterol content increases with increasing PUFA (89). Fortification of lipid foods, such as margarine, with plant sterols will dramatically increase the daily intake of phytosterols and significantly lower serum cholesterol (90). The dietary consumption of large amounts of plant sterols will interfere with cholesterol absorption, thereby leading to an increased daily neutral steroid excretion. 

Physical Activity Plant Stanols/Sterois Physical Activity ... 

Plant sterol and plant stanol esters and heart disease bamboo shoots, nuts, vegetable oils... 

Katan, M.B. S.M. Grundy P. Jones M. Law T. Miettinen R. Paoletti. Efficacy and safety of plant stanols and sterols in the management of blood cholesterol levels. Mayo Clin Proc. 2003, 78, 965-978. 

Natural mixed tocopherols (E306), natural D-a tocopherol, natural o-a tocopherol acetate, natural D-a tocopherol succinate from soybean sources Vegetable oil-derived phytosterols and phytosterol esters from soybean sources Plant stanol ester produced from vegetable oil sterols from soybean sources Whey used in distillates for spirits Lactitol... 

Nguyen, T.T., The cholesterol-lowering action of plant stanol esters, J. Nutr., 129, 2109-2112,1999. 

Phytosterols are nonnutrient bioactive substances and act as a structural component in the cell membranes, a role which in mammalian cells is played by cholesterol. The methyl or ethyl group at C-24 location makes them different from cholesterol [58]. They include plant sterols (unsaturated form) and plant stanols (saturated form). Both sterols and stanols are effective in lowering plasma total and LDL cholesterols and inhibit the absorption of cholesterol from the small intestine [59]. A wide spectrum of other biological activities in animals and humans has been reported, including anti-inflammatory [60], antibacterial [61], antioxidative [62], and anticancer activities [63]. P-Sitosterol, campesterol, stigmasterol, A -avenasterol, sitostanol, and campestanol are the most common representative members in this series. P-Sitosterol, campesterol, and stigmasterol are the major identified phytosterols in Brazil nut, with sitostanol, campestanol, and A -avenasterol present in trace amounts. 

Phytosterols (PS) are plant sterols or stands found in plants. Plant sterols belong to the triterpene family and differ from cholesterol by having a methyl or ethyl group in C24. Plant stanols, on the other hand, are the saturated form of the plant sterols (Fig. 113.1). PS are present in free or conjugated form as fatty-acyl esters, hydroxycinnamate steryl esters, steryl glycosides, or acylated steryl glycosides. The main function of plant sterols/stanols is to stabilize plant membranes and serve as precursors in the synthesis of steroidal saponins, alkaloids, and other steroids [1]. 

It is still a matter of controversy whether plant sterols and stanols are equally efficient in reducing cholesterol levels [28]. Some studies have shown that despite their different bioavailability, there is no clinical relevance with regard to their effect on total cholesterol, LDL-c, HDL-cholesterol, or triglyceride levels [25, 29]. Nevertheless, other authors have suggested that the differences in efficacy between plant sterols and plant stanols remain in the long-term interventions rather than in the shortterm studies [30]. For instance, in a recent meta-analysis of randomized placebo-controlled trials, decreases in LDL-c concentrations were dose-dependent for plant stanols but not for sterols. Similarly, intakes of plant stanols higher than 2 g day have been associated with additional and dose-dependent reductions in LDL-c [26]. Yet, this effect remains questionable [29]. It has been proposed that the difference in efficiency between these two compounds may be explained by the fact that plant stanols may reside longer in the intestine due to their lower absorption [31]. 

Stable statin treatment + plant sterols or plant stanol (2.5 g day each) Double-blind, randomized trial (54 patients on stable statin treatment) 85 weeks Increased reduction of LDL-c for both plant sterols (8.7%) and plant stanols (13.1%) compared to statin treatment alone [41]... 

Oat fS-glucan (5.0 g day ) + plant stanols (1.5 g day ) Randomized, controlled, 3-period crossover study (40 mildly hypercholesterolemic subjects) 4 weeks Slightly further [39] reduction of LDL-c of combined treatment (9.7%) compared to oat (3-glucan alone (5.1%)... 

Musa-Veloso K, Poon TH, Elliot JA, Chung C (2011) A comparison of the LDL-cholesterol lowering efficacy of plant stanols and plant sterols over a continuous dose range results of a meta-analysis of randomized, placebo-controlled trials. Prostag Leukotr Essent Fatty Acids 85(l) 9-28. doi 10.1016/j.plefa.2011.02.001... 

Miettinen TA, Gylling FI (2006) Plant stanol and sterol esters in prevention of cardiovascular diseases a review. Int J Clin Pharmacol Ther 44(6) 247-250... 

Naumaim E, Plat J, Kester ADM, Mensink RP (2008) The baseline serum lipoprotein profile is related to plant stanol induced changes in serum lipoprotein cholesterol and triacylglycerol concentrations. J Am Coll Nutr 27(1) 117-126... 

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