Study description

Immediately after birth, litters together with their mothers were distributed into three groups receiving three diets taking into account: day of birth, litter size, and genetic background of the mother. All diets were relabeled before entering the mouse facility and given in a blinded manner. After weaning, at 4 weeks of age, all mice were kept on the designated diet and were individually housed to accurately measure feed intake. The diets were: a) AIN93G synthetic pellets without the addition of any vitamin E (hereafter referred to as “low”, considering this diet still contains traces of vitamin E from the Casein protein source); b) AIN93G pellets containing medium levels (75 mg/kg) of vitamin E (all-rac-α-tocopheryl acetate; hereafter referred to as “medium”, which is normally present in this diet, and is slightly higher than the recommended dosage for mice); c) AIN93G pellets with addition of extra vitamin E to a final concentration of 375 mg/kg (hereafter referred to as “high”). Mice were analyzed at 8 and 12 weeks of age (Figure 1a).

a) Schematic view of the study design. The three diets used in the study are indicated by the horizontal elongated rectangles: white (low vitamin E diet: traces), grey (medium vitamin E diet: 75 mg/kg), black (high vitamin E diet: 375 mg/kg). Lower black line represents timeline with black dots representing key events during the study. b-d) α-Tocopherol measurements in the three diets: low, medium, high respectively. “Start” and “End” indicate the beginning and the final stage of the supplementation study. Error bars represent standard error of the mean (s.e.m.).