Fig. 1

Experimental design. As mentioned in the method section, briefly, the rats were randomized into the AL and RN groups. Then, each group was divided into five subgroups for five different sampling points, with 8 rats in each subgroup. The AL groups (fed ad libitum with normal chow for 4, 5, 6, 8, or 12 weeks, i.e. AL₄, AL₅, AL₆, AL₈, and AL₁₂, respectively) were age-matched controls of the RN groups. The RN groups were submitted to different feeding conditions and composed of a CR subgroup (fed with 60% of weight-matched normal chow for 4 weeks, also known as R₄), and four CUGA subgroups (refed with weight-matched normal chow for 1, 2, 4, or 8 weeks after 4-week CR, i.e. RN₁, RN₂, RN₄, and RN₈, respectively)