Phytosterol-Enriched Yogurt Increases LDL Affinity and Reduces CD36 Expression in Polygenic Hypercholesterolemia

Over-Expression of Intestinal Alkaline Phosphatase Attenuates Atherosclerosis

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Phytosterol Supplementation Could Improve Atherogenic and Anti-Atherogenic Apolipoproteins: A Systematic Review and Dose-Response Meta-Analysis of Randomized Controlled Trials

Phytosterol and phytostanol (PS) supplementation is reported to improve atherogenic and anti-atherogenic apolipoproteins (Apo). The purpose of the present study is to critically investigate the effectiveness of PS supplementation on Apo in adults.A comprehensive search was conducted of all randomized controlled trials (RCTs) conducted up to September 2018 in the following databases: PubMed, Web of Science, Cochrane Library, and Scopus. Mean difference with 95% confidence intervals (CIs) were pooled using a random-effects model (DerSimonian-Laird method).Fifty-one arms from 37 RCTs were included in the present meta-analysis. Findings showed that PS supplementation and fortification increased Apo-AI (weighted mean difference [WMD]: 0.014 mg/dl, 95% CI: 0.001, 0.028, p = 0.042) and Apo-CII (WMD: 0.303 mg/dl, 95% CI: 0.084, 0.523, p = 0.007) and lowered Apo-B (WMD: -0.063 mg/dl, 95% CI: -0.075, -0.051, p < 0.001), Apo-B/Apo-A-I ratio (WMD: -0.044 mg/dl, 95% CI: -0.062, -0.025, p < 0.001), and Apo-E (WMD: -0.255 mg/dl, 95% CI: -0.474, -0.036, p = 0.023). However, PS supplementation did not have significant effects on Apo-AII and Apo-CIII. PS supplementation or fortification significantly changes Apo-E (r = -0.137, p nonlinearity = 0.006) and Apo-CIII (r = 1.26, p nonlinearity = 0.028) based on PS dosage (mg/d) and Apo-CIII (r = 3.34, p nonlinearity = 0.013) and Apo-CII (r = 1.09, p nonlinearity = 0.017) based on trial duration (weeks) in a nonlinear fashion.Based on our findings, supplements or fortified foods containing PS might have a considerable favorite effect in achieving Apo profile target; however, due to high heterogeneity among included studies, results must be interpreted with caution.KEY TEACHING POINTSCardiovascular diseases (CVDs) recognized as main public health concern worldwide with considerable mortality of all global deaths.Apo-lipoproteins are amphipathic molecules involved in the lipoprotein metabolism which introduced as biomarkers in the evaluation of CVD risk.Phytosterols bioactive components of plants have important biological functions in cholesterol metabolism in humans.Here we showed that phytosterols and phytostanols improve apo-lipoproteins profile of humans; finding from meta-analysis of randomized controlled trials.Phytosterols supplementation lowered atherogenic apo-lipoproteins (Apo-B and Apo-E) and increased anti-atherogenic apo-lipoproteins (Apo-AI, Apo-CII).

Role of Functional Fortified Dairy Products in Cardiometabolic Health: A Systematic Review and Meta-analyses of Randomized Clinical Trials

There is insufficient evidence on the role of functional fortified dairy products in improving health and in preventing risk factors associated with noncommunicable chronic diseases. This systematic review was conducted to summarize effects of the consumption of fortified dairy products on biomarkers of cardiometabolic risk. MEDLINE and SCOPUS databases were used to perform searches to include studies published up to 30 April 2018. Randomized clinical trials with human subjects consuming dairy products fortified with phytosterols, FAs, vitamins or minerals and relating this consumption with cardiometabolic health were included in this review. Risk of bias assessment according to Cochrane guidelines was performed to determine the quality of the trials. Forty-one studies were finally selected for this synthesis; the selected studies tested dairy products fortified with the following nutrients and bioactive components: phytosterols (n = 31), FAs (n = 8), and vitamin D (n = 2). We found that the consumption of phytosterol-fortified dairy, led to an overall LDL cholesterol reduction of -0.36 (-0.41, -0.31) mmol/L, P < 0.001; this decrease was mainly related to the dosage. Likewise, consumption of ω-3 FA-fortified dairy products resulted in a plasma LDL cholesterol reduction of -0.18 (-0.27, -0.09) mmol/L as well as a decrease of -0.18 (-0.32, -0.05) mmol/L in triacylglycerols (TG). Performing meta-analyses of the consumption of dairy products fortified with vitamin D or FAs other than ω-3 FAs and biomarkers of cardiometabolic risk was not possible because of the few available publications. Our results indicate that consumption of dairy products fortified with phytosterols and ω-3 FAs can lead to a reduction of LDL cholesterol and consumption of fortified dairy products fortified with ω-3 FAs can reduce TG concentration. However, more studies with homogeneous designs are needed to determine the advantages of using dairy products as fortification vehicles to prevent cardiometabolic risk.

Intestinal CD36 and Other Key Proteins of Lipid Utilization: Role in Absorption and Gut Homeostasis

Several proteins have been implicated in fatty acid (FA) transport by enterocytes including the scavenger receptor CD36 (SR-B2), the scavenger receptor B1 (SR-B1) a member of the CD36 family and the FA transport protein 4 (FATP4). Here, we review the regulation of enterocyte FA uptake and its function in lipid absorption including prechylomicron formation, assembly and transport. Emphasis is given to CD36, which is abundantly expressed along the digestive tract of rodents and humans and has been the most studied. We also address the pleiotropic functions of CD36 that go beyond lipid absorption and metabolism to include recent evidence of its impact on intestinal homeostasis and barrier maintenance. Areas of progress involving contribution of membrane phospholipid remodeling and of cytosolic FA-binding proteins, FABP1 and FABP2 to fat absorption will be covered. © 2018 American Physiological Society. Compr Physiol 8:493-507, 2018.

Weekly Treatment of 2-Hydroxypropyl-β-cyclodextrin Improves Intracellular Cholesterol Levels in LDL Receptor Knockout Mice

Recently, the importance of lysosomes in the context of the metabolic syndrome has received increased attention. Increased lysosomal cholesterol storage and cholesterol crystallization inside macrophages have been linked to several metabolic diseases, such as atherosclerosis and non-alcoholic fatty liver disease (NAFLD). Two-hydroxypropyl-β-cyclodextrin (HP-B-CD) is able to redirect lysosomal cholesterol to the cytoplasm in Niemann-Pick type C1 disease, a lysosomal storage disorder. We hypothesize that HP-B-CD ameliorates liver cholesterol and intracellular cholesterol levels inside Kupffer cells (KCs). Hyperlipidemic low-density lipoprotein receptor knockout (Ldlr^−/−) mice were given weekly, subcutaneous injections with HP-B-CD or control PBS. In contrast to control injections, hyperlipidemic mice treated with HP-B-CD demonstrated a shift in intracellular cholesterol distribution towards cytoplasmic cholesteryl ester (CE) storage and a decrease in cholesterol crystallization inside KCs. Compared to untreated hyperlipidemic mice, the foamy KC appearance and liver cholesterol remained similar upon HP-B-CD administration, while hepatic campesterol and 7α-hydroxycholesterol levels were back increased. Thus, HP-B-CD could be a useful tool to improve intracellular cholesterol levels in the context of the metabolic syndrome, possibly through modulation of phyto- and oxysterols, and should be tested in the future. Additionally, these data underline the existence of a shared etiology between lysosomal storage diseases and NAFLD.

Milk phospholipid and plant sterol-dependent modulation of plasma lipids in healthy volunteers

PURPOSE

Hypolipidemic and/or hypocholesterolemic effects are presumed for dietary milk phospholipid (PL) as well as plant sterol (PSt) supplementation. The aim was to induce changes in plasma lipid profile by giving different doses of milk PL and a combination of milk PL with PSt to healthy volunteers.

METHODS

In an open-label intervention study, 14 women received dairy products enriched with moderate (3 g PL/day) or high (6 g PL/day) dose of milk PL or a high dose of milk PL combined with PSt (6 g PL/day + 2 g PSt/day) during 3 periods each lasting 10 days.

RESULTS

Total cholesterol concentration and HDL cholesterol concentration were reduced following supplementation with 3 g PL/day. No significant change in LDL cholesterol concentration was found compared with baseline. High PL dose resulted in an increase of LDL cholesterol and unchanged HDL cholesterol compared with moderate PL dose. The LDL/HDL ratio and triglyceride concentration remained constant within the study. Except for increased phosphatidyl ethanolamine concentrations, plasma PL concentrations were not altered during exclusive PL supplementations. A combined high-dose PL and PSt supplementation led to decreased plasma LDL cholesterol concentration, decreased PL excretion, increased plasma sphingomyelin/phosphatidyl choline ratio, and significant changes in plasma fatty acid distribution compared with exclusive high-dose PL supplementation.

CONCLUSION

Milk PL supplementations influence plasma cholesterol concentrations, but without changes of LDL/HDL ratio. A combined high-dose milk PL and PSt supplementation decreases plasma LDL cholesterol concentration, but it probably enforces absorption of fatty acids or fatty acid-containing hydrolysis products that originated during lipid digestion.

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

PURPOSE

To determine if plant stanols and plant sterols differ with respect to their low-density lipoprotein cholesterol (LDL-CH) lowering efficacies across a continuous dose range.

METHODS

Dose-response relationships were evaluated separately for plant stanols and plant sterols and reductions in LDL-CH, using a first-order elimination function.

RESULTS

Altogether, 113 publications and 1 unpublished study report (representing 182 strata) complied with the pre-defined inclusion and exclusion criteria and were included in the assessment. The maximal LDL-CH reductions for plant stanols (16.4%) and plant stanol ester (17.1%) were significantly greater than the maximal LDL-CH reductions for plant sterols (8.3%) and plant sterol ester (8.4%). These findings persisted in several additional analyses.

DISCUSSION AND CONCLUSIONS

Intakes of plant stanols in excess of the recommended 2g/day dose are associated with additional and dose-dependent reductions in LDL-CH, possibly resulting in further reductions in the risk of coronary heart disease (CHD).

Hepatic nuclear sterol regulatory binding element protein 2 abundance is decreased and that of ABCG5 increased in male hamsters fed plant sterols

The effect of dietary plant sterols on cholesterol homeostasis has been well characterized in the intestine, but how plant sterols affect lipid metabolism in other lipid-rich tissues is not known. Changes in hepatic cholesterol homeostasis in response to high dietary intakes of plant sterols were determined in male golden Syrian hamsters fed hypercholesterolemia-inducing diets with and without 2% plant sterols (wt:wt; Reducol, Forbes Meditech) for 28 d. Plasma and hepatic cholesterol concentrations, cholesterol biosynthesis and absorption, and changes in the expression of sterol response element binding protein 2 (SREBP2) and liver X receptor-beta (LXRbeta) and their target genes were measured. Plant sterol feeding reduced plasma total cholesterol, non-HDL cholesterol, and HDL cholesterol concentrations 43% (P < 0.0001), 60% (P < 0.0001), and 21% (P = 0.001), respectively, compared with controls. Furthermore, there was a 93% reduction (P < 0.0001) in hepatic total cholesterol and >6-fold (P = 0.029) and >2-fold (P < 0.0001) increases in hepatic beta-sitosterol and campesterol concentrations, respectively, in plant sterol-fed hamsters compared with controls. Plant sterol feeding also increased fractional cholesterol synthesis >2-fold (P < 0.03) and decreased cholesterol absorption 83% (P < 0.0001) compared with controls. Plant sterol feeding increased hepatic protein expression of cytosolic (inactive) SREBP2, decreased nuclear (active) SREBP2, and tended to increase LXRbeta (P = 0.06) and ATP binding cassette transporter G5, indicating a differential modulation of the expression of proteins central to cholesterol metabolism. In conclusion, high-dose plant sterol feeding of hamsters changes hepatic protein abundance in favor of cholesterol excretion despite lower hepatic cholesterol concentrations and higher cholesterol fractional synthesis.

Review article: effects of plant sterols and stanols beyond low-density lipoprotein cholesterol lowering

Consumption of foods and supplements enriched with plant sterols/stanols (PS) may help reduce low-density lipoprotein cholesterol (LDL-C) levels. In this review, we consider the effects of PS beyond LDL-C lowering. Plant sterols/stanols exert beneficial effects on other lipid variables, such as apolipoprotein (apo) B/apoAI ratio and, in some studies, high-density lipoprotein cholesterol (HDL-C) and triglycerides (TG). Plant sterols/stanols may also affect inflammatory markers, coagulation parameters, as well as platelet and endothelial function. Evidence also exists about a beneficial effect on oxidative stress, but this does not seem to be of greater degree than that expected from the LDL-C lowering. Many of these effects have been demonstrated in vitro and animal models. Some in vitro effects cannot be seen in vivo or in humans at usual doses. The epidemiological studies that evaluated the association of plasma PS concentration with cardiovascular disease (CVD) risk do not provide a definitive answer. Long-term randomized placebo-controlled studies are required to clarify the effects of supplementation with PS on CVD risk and progression of atherosclerosis.