METHODS: Ten healthy volunteers were given four different doses of vitamin E formulations (268 mg α-T, 537 mg α-T, 263 mg TRF or 526 mg TRF) in a cross-over postprandial trial. Blood was sampled at 0, 2, 4, 5, 6 and 8 hours after meal consumption and plasma antioxidant status including total glutathione, superoxide dismutase, malondialdehyde (MDA), ferric reducing antioxidant potential and trolox-equivalent antioxidant capacity, was analyzed.
RESULTS: Supplementation with the different doses of either α-T or TRF did not significantly improve overall antioxidant status. There was no significant difference in overall antioxidant status among treatments at the different doses compared. However, a significant dose-response effect was observed for plasma MDA throughout the 8-hour postprandial period. MDA was significantly lower after the 537 mg α-T treatment, compared to the 268 mg α-T treatment; it was also lower after the 526 mg TRF treatment compared to the 263 mg TRF treatment (P
OBJECTIVE: The primary study objective was to evaluate the postprandial fate of tocotrienols and alpha-tocopherol in human plasma and lipoproteins.
DESIGN: Seven healthy volunteers (4 males, 3 females) were administered a single dose of vitamin E [1011 mg palm tocotrienol-rich fraction (TRF) or 1074 mg alpha-tocopherol] after a 7-d conditioning period with a tocotrienol-free diet. Blood was sampled at baseline (fasted) and 2, 4, 5, 6, 8, and 24 h after supplementation. Concentrations of tocopherol and tocotrienol isomers in plasma, triacylglycerol-rich particles (TRPs), LDLs, and HDLs were measured at each interval.
RESULTS: After intervention with TRF, plasma tocotrienols peaked at 4 h (4.79 +/- 1.2 microg/mL), whereas alpha-tocopherol peaked at 6 h (13.46 +/- 1.68 microg/mL). Although tocotrienols were similarly detected in TRPs, LDLs, and HDLs, tocotrienol concentrations were significantly lower than alpha-tocopherol concentrations. In comparison, plasma alpha-tocopherol peaked at 8 h (24.3 +/- 5.22 microg/mL) during the alpha-tocopherol treatment and emerged as the major vitamin E isomer detected in plasma and lipoproteins during both the TRF and the alpha-tocopherol treatments.
CONCLUSIONS: Tocotrienols are detected in postprandial plasma, albeit in significantly lower concentrations than is alpha-tocopherol. This finding confirms previous observations that, in the fasted state, tocotrienols are not detected in plasma. Tocotrienol transport in lipoproteins appears to follow complex biochemically mediated pathways within the lipoprotein cascade.
PURPOSE: This paper explores the effects of SQ in CVD.
METHODS: A systematic review of the literature was performed to identify relevant studies about SQ and CVD. A comprehensive search in Medline and Scopus for relevant studies published between the years 1946 and 2019 was performed. The main inclusion criteria were that the study was published in English; that the study reported association or effect of SQ and CVD; and that CVD should be related to lifestyle variables, aging, or experimentally induced conditions.
RESULTS: The literature searches identified 5562 potentially relevant articles, whereby 21 studies met the inclusion criteria. There were three human studies and 18 animal experimental studies included in this paper. Only one human study reported positive outcome of SQ in CVD. The remaining two studies reported inconsistent and/or no effect. For animal studies, 15 studies reported positive effect while the remaining reported negative and/or no effect of SQ on various related parameters.
CONCLUSIONS: This evidence-based review emphasizes the potential of SQ being used for cardiovascular-related diseases. The effect of SQ, especially of plant-based warrants further exploration. Controlled human observational studies should be performed to provide comprehensive evidence.