News | 27 February 2018

Do plant sterols and stanols reduce liver inflammation?

Plant sterol and stanol esters are well known functional food ingredients with a long proven history of lowering blood (LDL-) cholesterol concentrations via inhibiting intestinal cholesterol absorption (Gylling et al, 2014) . Over 120 controlled human intervention studies have shown that serum LDL-cholesterol concentrations can be reduced by 7-12.5% with a daily intake of 1.5 - 3 g plant sterols or stanols (Ras et al, 2014).

Lately, there is an increasing attention for the effects of plant sterols and stanols beyond lowering serum LDL-cholesterol. A first example of this was the observation that also serum triacylglycerol (TAG) concentrations were reduced in subjects with elevated TAG concentrations (Naumann et al 2008; Demonty et al 2013). This was found both in humans and later confirmed more mechanistically in animal studies showing that this effect could be explained via a reduced hepatic production of TAG rich large very low-density lipoprotein (VLDL1) particles (Plat & Mensink, 2009). More recently, researchers from Maastricht University found in an accepted animal model for studying non-alcoholic steatohepatitis (NASH), that plant sterol and stanol esters reduced inflammation in the liver (Plat et al, 2014).

Recently, researchers from the Maastricht University supported by three well-known companies in the area of producing plant sterol and stanol esters and marketing foods with added plant sterol and stanol esters (BASF, Raisio and Unilever) received a PPS allowance from the Dutch Ministry of Economic Affairs by means via the Top Sector Life Sciences & Health to stimulate public-private partnerships to further study whether liver inflammation can be prevented by plant sterols and stanols in humans including patients with NASH. BASF, Raisio and Unilever are founding members of the International Plant Sterol and Stanol Association (IPSSA) whose mission is to educate the public about the role of a healthy diet and lifestyle in reducing the risk of heart disease and how plant sterols and stanols have been scientifically proven to lower blood LDL-cholesterol. The TKI funded research project containing two sequential intervention studies will start early April with a first placebo-controlled study carried out at the Maastricht University Medical Center (MUMC). In this first study with a follow-up of 1 year, patients that were recently diagnosed for having liver inflammation by a liver biopsy will consume margarines providing 3 g/d of either plant sterols or stanols compared to placebo. Besides effects on liver inflammation, also changes in hepatic insulin sensitivity and lipoprotein metabolism will be explored using the infrastructure of the Metabolic Research Unit Maastricht (MRUM).

References
Gylling H, Plat J, Turley S, Ginsberg HN, Ellegard L, Jessup W, et al. Plant sterols and plant stanols in the management of dyslipidaemia and prevention of cardiovascular disease. Atherosclerosis. 2014;232(2):346-60.

Ras RT, Geleijnse JM, Trautwein EA. LDL-cholesterol-lowering effect of plant sterols and stanols across different dose ranges: a meta-analysis of randomised controlled studies. Br J Nutr. 2014;112(2):214-9.

Naumann E, Plat J, Kesler AD, Mensink RP. The baseline serum lipoprotein profile is related to plant stanol induced changes in serum lipoprotein cholesterol and triacylglycerol concentrations. Journal of the American College of Nutrition. 2008;27(1):117-26.

Demonty I, Ras RT, van der Knaap HC, Meijer L, Zock PL, Geleijnse JM, et al. The effect of plant sterols on serum triglyceride concentrations is dependent on baseline concentrations: a pooled analysis of 12 randomised controlled trials. Eur J Nutr. 2013;52(1):153-60.

Plat J, Mensink RP. Plant Stanol Esters Lower Serum Triacylglycerol Concentrations via a Reduced Hepatic VLDL-1 Production. Lipids. 2009;44(12):1149-53.

Plat J, Hendrikx T, Bieghs V, Jeurissen ML, Walenbergh SM, van Gorp PJ, De Smet E, Konings M, Vreugdenhil ACE, Guichot YD, Rensen SS, Buurman WA, Greve JW, Lütjohann D, Mensink RP, Shiri-Sverdlov R. Protective role of plant sterol and stanol esters in liver inflammation: insights from mice and humans. PLoS One. 2014;30:9.