Milk enriched with phytosterols reduces plasma cholesterol levels in healthy and hypercholesterolemic subjects

The anti-inflammatory potential of a moderately hydrolysed casein and its 5 kDa fraction in in vitro and ex vivo models of the gastrointestinal tract

Bioactive peptides from milk can impart a wide range of physiological benefits without the allergies and intolerance associated with the consumption of whole milk. The objective of this study was to characterise the anti-inflammatory properties of intact sodium caseinate (NaCAS), a moderately hydrolysed NaCAS enzyme hydrolysate (EH) and its 5 kDa fraction (5kDaR), in both in vitro and ex vivo systems. In vitro, Caco-2 cells were stimulated with tumor necrosis factor (TNF) α and co-treated ± casein hydrolysates or dexamethasone (control). The inflammatory marker interleukin (IL)-8 was measured by ELISA in the supernatant at 24 h. Ex vivo, porcine colonic tissues were stimulated with lipopolysaccharide (LPS) and co-treated with casein hydrolysates for 3 h from which the relative expression of a panel of cytokines was measured in vitro. While the steroid dexamethasone brought about a 41.6% reduction in the IL-8 concentration in the supernatant, the 5kDaR reduced IL-8 by 59% (P < 0.05) when compared to the TNFα stimulated Caco-2 cells. In the ex vivo system, 5kDaR was associated with decreases in IL-1α, IL-1β, IL-8 and TGF-β expression and an increase in IL-17 expression (P < 0.05) relative to the LPS challenged tissues. We concluded, that a 5 kDa casein fraction demonstrates potent anti-inflammatory effects both in in vitro and ex vivo models of the gastrointestinal tract.

Anti-hypercholesterolemic effect of Pistacia lentiscus fatty oil in egg yolk-fed rabbits: a comparative study with simvastatin

AIM

The current study was undertaken to assess anti-hyperlipidemic activity of Pistacia lentiscus fatty oil (PLFO) in rabbits following a hyperlipidemic diet.

METHOD

Twenty healthy female (WNZ) rabbits were divided into four groups of five animals each: (a) normal control (NC group) receiving standard diet, (b) hyperlipidemic control (EY) group receiving standard diet and gavaged daily with egg yolk (10 mL), (c) hyperlipidemic + PLFO (EY + PLFO) group receiving as the EY group and treated daily with PLFO (2 mL/kg BW, (d) hyperlipidemic + simvastatin (EY + SVS) group receiving as the EY group and treated once daily with 2.5 mg/kg BW of simvastatin. At the end of the six-week experimental period, the lipidemic profiles of the different groups were investigated.

RESULTS

In the EY group, the egg yolk resulted in a significant increase of total cholesterol (TC), triglycerides (TG), HDL-C, LDL-C, and the LDL-C/HDL-C ratio. Both the EY + PLFO and EY + SVS groups, when compared to the EY group, showed a significant decrease of TC, TG, LDL-C, and the LDL-C/HDL-C ratio. However, with respect to HDL-C the differences were not significant. The TGs were significantly lower (P < 0.001) in the simvastatin-treated group when compared to rabbits treated in the PLFO group.

CONCLUSION

The study concludes that P. lentiscus fatty oil (PLFO) possesses anti-hyperlipidemic properties at least in reducing total cholesterol, LDL-cholesterol and triglycerides.

Antiatherosclerotic Effect of Canarium odontophyllum Miq. Fruit Parts in Rabbits Fed High Cholesterol Diet

The effect of C. odontophyllum (CO) fruit parts was investigated in hypercholesterolemic rabbits. Forty-nine rabbits, which were randomly divided into seven groups of seven animals (n = 7), received a diet containing different parts of CO fruit parts for 8 weeks. The groups were as follows: (1) normal diet: NC group and (2) hypercholesterolemic diet: PC, HS (10 mg/kg/day simvastatin), HPO (20 g kg(-1) oil extracted from the pulp of CO), HKO (20 g kg(-1) oil extracted from the kernel of CO), HF (50 g kg(-1) fullfat pulp of CO), and HD (50 g kg(-1) defatted pulp of CO). Among these groups, rabbits receiving defatted pulp of CO showed the greatest cholesterol lowering effect as it had reduced plasma LDL-C, TC, and thiobarbiturate reactive substance (TBARS) levels as well as atherosclerotic plaques. The presence of high dietary fiber and antioxidants activity are potential factors contributing to the cholesterol lowering effect. Consequently, these results indicate the potential use of CO defatted pulp as a cholesterol lowering and antioxidant agent.

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).

Solubility Limits of Cholesterol, Lanosterol, Ergosterol, Stigmasterol, and β-Sitosterol in Electroformed Lipid Vesicles

Here we use nuclear magnetic resonance to measure the solubility limit of several biologically relevant sterols in electroformed giant unilamellar vesicle membranes containing phosphatidylcholine (PC) lipids in ratios of 1:1:X DOPC:DPPC:sterol. We find solubility limits of cholesterol, lanosterol, ergosterol, stigmasterol, and β-sitosterol to be 65-70%, ~35%, 30-35%, 20-25%, and ~40%, respectively. The low solubilities of stigmasterol and β-sitosterol, which differ from cholesterol only in their alkyl tails, show that subtle differences in tail structure can strongly affect sterol solubility. Below the solubility limits, the fraction of sterol to PC-lipid in electroformed vesicles linearly reflects the fraction in the original stock solutions used in the electroformation process.