Zesílení účinku vit. E
ALPL
- Enzym fungující v alkalickém přostředí
- Zásadní význam pro růst a vývoj kostí a zubů - mineralizace
- Akumulace fosforu a vápníku
- Ovlivňuje hladiny vitamínu B6
APOA5
- APOA gene has been reported to predispose carriers to elevated concentrations of TG and vitamin E [5]
CYP4F2 variant Rs2108622
- Associated with increased serum alpha-tocopherol in subjects from the ATBC trial
- This variant has reduced omega-hydroxylation activity (Major et al., 2012).
Variants in genes involved in lipid absorption, transport, uptake and metabolism
- May modulate alpha-tocopherol absorption, transport and intracellular metabolism
- May influence plasma alpha-tocopherol concentrations (Zingg et al., 2008)
Interaction with selenium, niacin and vitamin K
Selenium and niacin
- Required to maintain glutathione peroxidase activity
- Membrane-specific isoenzyme of glutathione peroxidase
- Catalyses the reduction of the tocopheroxyl radical back to tocopherol
- Glutathione peroxidase reduces hydrogen peroxide radicals
- Alpha-tocopherol is involved in removing the products of attack by these radicals on lipids (Bender, 2003).
A competitive inhibition of vitamin K-dependent gamma-carboxylase
- By tocopherol quinone and the phylloquinone hydroquinone
- Gamma-carboxylase is required for the conversion of specific glutamyl residues to gamma-carboxyglutamyl residues in certain proteins involved in normal haemostatic function (Furie et al., 1999)
- Factors II,
- F. VII,
- F. IX
- F. X
- proteins C
- Prot. S
Interaction with vitamin C
- vitamin C can reduce the oxidised form of alpha-tocopherol
Smokers
- Higher plasma F2-isoprostane concentrations
- Faster plasma alpha-tocopherol disappearance rates than non-smokers
- When they received vitamin C supplementation (500 mg twice daily) for two weeks
- Alpha-tocopherol disappearance rates were normalised (Bruno et al., 2005; Bruno et al., 2006a) [2]