reSeArcH Article
Extended Data Fig. 1 | Cold-induced changes in circulating metabolites
in mice and humans. a, Representative EMG in adult humans at 27 °C
and following cold exposure at 19 °C for 2 h. Voluntary muscle contraction
as a positive control of EMG recording. b, c, Serum non-esterified fatty
acids (NEFA) (b) and blood glucose (c) levels in high- (n = 9) and low-
BAT subjects (n = 6) at thermoneutral 27 °C (TN) and following cold
exposure at 19 °C. d, Correlation between BAT activity (SUV, log 10 ) and
cold-induced changes in serum amino acid levels of high- (red dots) and
low-BAT subjects (blue dots). n = 33 per group (all amino acids) except
n = 29 (Asp). e, Correlation between fat-free mass (kg) and changes in
serum total BCAAs in d. n = 33. f, Changes in plasma BCAA levels at
thermoneutral (30 °C) or cold exposure (15 °C) in diet-induced obese
mice. n = 8 (TN), n = 7 (cold). b–f, Biologically independent samples.
Data are mean ± s.e.m.; two-sided P values by paired t-test (b, c) or two-
way repeated-measures ANOVA followed by post hoc paired or unpaired
t-tests with Bonferroni’s correction (f). Pearson’s (r) or Spearman’s rank
correlation coefficient (rs) was calculated, as appropriate (d, e).