Se-FA reduces Hcy levels and increases Met levels in 3×Tg- and 2×Tg-AD mice. (a–d) Hcy levels in the serum (a,c), cortex and hippocampus (b,d) of 7-month-old 3×Tg- and 2×Tg-AD mice measured by ELISA (n = 3 or 6 mice). Se-FA: normal-dose Se-FA (Se 3 μg/g and folate 36 μg/g). Se-FA-L: low-dose Se-FA, half of normal-dose Se-FA. (e) A pattern of THF and Met cycles in the metabolism of Hcy. (f,g) Levels of FA, VB6, VB12, Met and MS in the serum (f) and cortex (g) of 7-month-old 3×Tg-AD mice (n = 3, 4 or 5 mice). All the mice were fed diets with Se-FA or a control diet for 12 weeks. All data are presented as the mean ± SEM. * p < 0.05, ** p < 0.01, *** p < 0.001 as determined by one-way ANOVA followed by Dunnett’s multiple comparison test.