Fatty acid moieties have little effect on cholesterol‐lowering potency of plant sterol esters

Abstract

Plant sterol esters are the popular cholesterol-lowering dietary supplements. In order to understand the role of fatty acid moieties in the cholesterol-lowering activity of plant sterol esters, the present study was to: (i) compare the cholesterol-lowering activity of sterol esters of sunflower oil (SSF) with that of sterol esters of canola oil (SCO); and (ii) to systematically investigate the effect of SSF and SCO on the gene expression of sterol transporters, enzymes, receptors and proteins involved in cholesterol metabolism in hamsters fed a high cholesterol diet. GC analysis showed that SSF and SCO had similar sterol profile but they had different fatty acid moieties. Results showed both SSF and SCO could equally reduce plasma cholesterol in a dose-dependent manner. Both SSF and SCO could inhibit the cholesterol absorption and enhance the excretion of bile acids. In the similar ways, dietary SSF and SCO could up-regulate hepatic cholesterol-7a-hydroxylase (CYP7A1) and down-regulate intestinal sterol transporter Niemann-Pick C1-like 1 (NPC1L1), acyl coenzyme A: cholesterol acyltransferase 2 (ACAT2) and hepatic 3-hydroxy-3-methylglutaryl-CoA reductase (HMG-CoA reductase). It was concluded that the fatty acid moieties had little effect on the cholesterol-lowering activity of SSF and SCO.Practical applications: Plant sterols are effective in reducing plasma cholesterol. Commercially, plant sterol esters of sunflower oil and plant sterol esters of canola oil are mostly used for this purpose. The present study found that SSF and SCO were equally effective in reducing plasma cholesterol in a dose-dependent manner regardless the significant difference in their fatty acid compositions.

Plasma triacylglycerol‐lowering activity of citrus polymethoxylated flavones is mediated by modulating the genes involved in lipid metabolism in hamsters

“…Four diets were prepared as previously described with minor modifications . A non‐cholesterol diet (NCD) was prepared by mixing the following powdered ingredients per kg diet: cornstarch, 507 g; casein, 242 g; lard, 50 g; sucrose, 119 g; mineral mix , 40 g; vitamin mix , 20 g; gelatin, 20 g; DL‐Methionine, 1 g (Table ).…”

“…Cholesterol concentration in the liver was measured as we previously described . In brief, the liver tissue (100 mg) was extracted using chloroform–methanol (2:1, v/v) with addition of 5α‐cholestane (1.0 mg) as an internal standard, followed by saponification.…”

“…mRNA of SREBP1c, FAS, PPARα, and LPL in the liver or epididymal fat pad as well as hepatic 3‐hydroxy‐3‐methyl‐glutaryl‐CoA reductase (HMG‐COA‐R), low‐density lipoprotein receptor (LDL‐R), cholesterol 7 alpha‐hydroxylase (CYP7A1), and MTP were quantified as previously described . Total RNA of liver was extracted using Trizol reagent (Invitrogen, Carslbad, CA), while total RNA of epididymal fat pad was extracted by QIAzol lysis reagent (Qiagen, Valencia, CA, USA) followed by purification with GenElute™ Mammalian Total RNA Miniprep Kit (Sigma, St. Louis, MO, USA).…”

Serum phytosterols associate with T helper 1 cytokine concentration in pregnant women

“…Serum noncholesterol steroids from mothers or newborns' cord blood were analyzed using a method modified from which we previously described (Liu et al, 2015(Liu et al, , 2017. In brief, total serum lipids were extracted using a mixture of chloroform and methanol (2:1, vol/vol) with the addition of 5α-cholestane as an internal standard, followed by saponification.…”

Plant Sterols: Chemical and Enzymatic Structural Modifications and Effects on Their Cholesterol-Lowering Activity

“…Liu et al compared the cholesterol-lowering activity of sterol esters of sunflower oil and the sterol esters of canola oil, showing that they were equally effective in reducing plasma cholesterol in a dose-dependent manner regardless of the significant differences in their fatty acid compositions. 159 However, the research conducted by Rasmussen et al demonstrated that plant sterol esters made with beef tallow and pure stearic acid were more effective than plant sterol esters made with soybean oil in reducing the cholesterol absorption, liver cholesterol, and plasma non-HDL cholesterol concentration. 160 It was also shown that the sterol esters with fish oil had an greater influence on LDL cholesterol concentrations compared with the esters with vegetable oil.…”