(A and B) Representative immunoblots and quantification of UCP1 protein expression in (A) IWAT and (B) BAT of chow fed CD mice treated for 40 d with antibiotics and GF mice, acclimated to 22 °C or 4 °C (n = 5–8).
(C) Representative immunoblots and quantification of UCP1 protein expression in IWAT and BAT of CD mice exposed to 4 °C for 48 h (n = 5).
(D) Core body temperatures prior to and during acute cold challenge at 4 °C (n = 5).
(E and F) VO2 values in response to subcutaneous injection (arrow) of CL316,243 (solid line) or saline (dotted line) in (E) mice fed chow and acclimated to 22 °C and (F) mice fed palm oil-based HFD for 4 w and acclimated to 30 °C; Inset barplots display the AUC for saline and CL316,243 as well as the response, AUC of saline subtracted from CL316,243 (n = 4–8).
(G and H) Representative immunoblots and quantification of UCP1 protein expression in (G) IWAT and (H) BAT of CD and GF mice acclimated to 30 °C and fed a palm oil-based HFD for 4 w (n = 3–6).
(I) Representative image and surface temperatures of BAT and IWAT in mice acclimated to 22 °C. Arrow indicates BAT (upper panel) and IWAT (lower panel) (n = 3–6).
(J) Rates of FAO in BAT (n = 4–6).
AUC values were adjusted by ANCOVA for corrected body mass. Circles represent individual mice; Barplots represent means ± s.e.m; Solid and dashed lines represent means. Statistical analyses were conducted using Student’s t-test or 2-way ANOVA with repeated measures where appropriate; *P < 0.05 control vs. CD or GF mice. See also Figure S2.