Urinary oxidized, but not enzymatic vitamin E metabolites are inversely associated with measures of glucose homeostasis in middle-aged healthy individuals.
Clinical nutrition (Edinburgh, Scotland)
BACKGROUND & AIMS: Damage induced by lipid peroxidation has been associated with impaired glucose homeostasis. Vitamin E (α-tocopherol, α-TOH) competitively reacts with lipid peroxyl radicals to mitigate oxidative damage, and forms oxidized vitamin E metabolites. Accordingly, we aimed to investigate the associations between α-TOH metabolites (oxidized and enzymatic) in both circulation and urine and measures of glucose homeostasis in the general middle-aged population.
METHODS: This cross-sectional study was embedded in the population-based Netherlands Epidemiology of Obesity (NEO) Study. α-TOH metabolites in blood (α-TOH and α-CEHC-SO
RESULTS: We included 498 participants (45% men) with mean (SD) age of 55.8 (6.1) years who did not use glucose-lowering medication. While blood α-TOH was not associated with measures of glucose homeostasis, urinary oxidized metabolites (α-TLHQ-SO
CONCLUSION: Higher urinary levels of oxidized α-TOH metabolites as well as higher oxidized-to-enzymatic α-TOH metabolite ratio, but not circulating α-TOH or enzymatic metabolites, were associated with lower insulin resistance. Rather than circulating α-TOH, estimates of the conversion of α-TOH might be informative in relation to health and disease.
Luo J, Meulmeester FL, Martens LG, Ashrafi N, de Mutsert R, Mook-Kanamori DO, Rosendaal FR, Willems van Dijk K, le Cessie S, Mills K, Noordam R, van Heemst D. Urinary oxidized, but not enzymatic vitamin E metabolites are inversely associated with measures of glucose homeostasis in middle-aged healthy individuals. Clin Nutr. 2021 Jun;40(6):4192-4200. doi: 10.1016/j.clnu.2021.01.039. Epub 2021 Feb 3. PMID: 33593663.