Figure 4. Rapamycin reverses the downregulated UCP1 protein in brown adipose tissue of Lmna−/− mice.
(A) Tested model for the role of mTOR activity in the expression of UCP1 protein in brown adipose tissue (BAT). (B-D) Western blots of mTORC1 activity in Lmna+/+ and Lmna−/− mice treated with rapamycin. Relative p-S6 levels (normalized to S6) were quantified. (E-G) Western blots of mTORC2 activity of Lmna+/+ and Lmna−/− mice treated with rapamycin. Relative p-Akt levels (normalized to Akt) were quantified. (H-J) Rapamycin increases UCP1 in BAT of Lmna−/− mice. Relative UCP1 levels (normalized to GAPDH) were quantified. (K) Body surface temperature of Lmna+/+ and Lmna−/− mice treated with rapamycin. Mice treated with vehicle (WT, black square, n = 4; KO, black circle, n = 11) or rapamycin (WT, red square, n = 5; KO, red circle, n = 11) were measured every other day. Symbols represent mean body surface temperature ± SEM. Data from males and females are combined. (L) Western blots of UCP1 levels in preadipocytes derived from BAT of Lmna−/− mice. Representative blots were shown from 5 Lmna−/− mice. WT: wild type (Lmna+/+). KO: knockout (Lmna−/−). Rapa: rapamycin. Each value is mean ± SEM for the number of mice indicated in parentheses. P values were derived from unpaired two-tailed Student’s t-test.