Effects of plant sterol- or stanol-enriched margarine on fasting plasma oxyphytosterol concentrations in healthy subjects

Abstract

Background: Consumption of plant sterols and plant stanols reduces low-density lipoprotein cholesterol (LDL-C) concentrations. At the same time, plasma plant sterol concentrations will increase after plant sterol consumption, but decrease after plant stanol consumption. In contrast to plant stanols, plant sterols can undergo oxidation and form oxyphytosterols. Findings from in vitro and animal studies suggest that oxyphytosterols might be atherogenic. Objective: The objective was to examine whether plant sterol and stanol consumption changes fasting plasma oxyphytosterol concentrations. Design: A randomized, double blind, cross-over study was performed in which 43 healthy subjects (18e70 years) consumed for 4 weeks a plant sterol-enriched (3.0 g/d of plant sterols), a plant stanol-enriched (3.0 g/d of plant stanols), and a control margarine separated by wash-out periods of 4 weeks. Oxyphytosterol concentrations were determined in BHT-enriched plasma via GCeMS. Results: Compared to control, serum LDL-C concentrations were reduced after plant sterol (À8.1%; p < 0.001) and plant stanol consumption (À7.8%; p < 0.001). Plant sterol consumption did not change plasma oxyphytosterol concentrations. On the other hand, intake of the plant stanol margarine reduced 7b-OH-campesterol by 0.07 ng/mL (w14%; p < 0.01) and by 0.07 ng/mL (w15%; p < 0.01) compared with the control and sterol margarines, respectively. When standardized for serum cholesterol, effects on these oxyphytosterols were comparable. In addition, plant stanol intake reduced cholesterolstandardized 7-keto-campesterol levels compared with plant sterol intake (p < 0.05). Conclusions: Daily consumption of a plant sterol-enriched margarine does not increase oxyphytosterol concentrations, while plant stanol consumption may reduce the concentrations of the oxidative plant sterol metabolites 7b-OH-campesterol and 7-keto-campesterol. This trial is registered at clinicaltrials.gov as NCT01559428.

Oxysterols formation: A review of a multifactorial process

“…Nevertheless, oxysitosterol plasma levels are usually higher than campesterols levels, probably due to in vivo oxidation of sterols (67). Considering the higher campesterol oxidation rate compared to sitosterol, as reported in our work, higher potential toxicity of campesterol-enriched foods could be hypothesized.…”

Vascular effects of oxysterols and oxyphytosterols in apoE −/− mice

“…Thus, higher plasma plant sterol concentrations may translate into higher plasma oxyphytosterol concentrations. Intervention trials found conflicting results whether the consumption of a plant sterolenriched margarine for 4 weeks increases plasma 7-ßeOHecampesterol concentrations in healthy individuals [10,12]. Differences with regard to the post-prandial state, the genetic background and different duration of the wash out periods may explain the heterogenicity of the data, however, additional research is needed to address the relation of specific diets with plasma oxyphytosterol concentrations.…”

Cholesterol and stigmasterol within a sunflower oil matrix: Thermal degradation and oxysterols formation

“…The incorporation of these exogenously formed oxysterols into the organism through the diet has been widely discussed. Although the intestinal absorption of these compounds (both from cholesterol and plant sterols) has been demonstrated [7][8][9], the relevance of phytosterol absorption versus endogenous formation of these compounds is still under debate, and some scientific evidence has been achieved [10][11]. So, assessment and control of factors affecting sterol oxidation in foodstuffs is a matter of interest for food safety purposes.…”