Five-week-old male C57BL/6J
mice were purchased from Clea Japan (Tokyo). These
animals were fed a commercial diet (CE-2, Clea Japan)
and tap water ad libitum, and housed for 1 week before
the experiments at 23 1 C and a relative humidity of
55 5% with a constant light/dark cycle (lights on
from 7:00 a.m. to 7:00 p.m.). All animal experiments
were performed under the guidelines established by
the Japanese Society of Nutrition and Food Science
(Law No. 105 and Notification No. 6 of the Japanese
Government).