Fig. 1: Season of fertilization predetermines the metabolic fate of brown adipose tissue in human adults.
From: Pre-fertilization-origin preservation of brown fat-mediated energy expenditure in humans
a, Study protocol for investigating intergenerational control of BAT in humans. BAT activity and density were assessed by 18F-FDG-PET/CT following acute cold exposure and NIR-TRS, respectively. The day of fertilization was estimated based on the day of birth. Seasons of birth and fertilization were determined according to the participant’s days of birth and fertilization as depicted in Extended Data Fig. 1b. b, Cold-induced BAT activity assessed as FDG uptake value (standardized uptake value; SUV) of the high and low BAT groups in Cohort 1. High BAT group (n = 259), low BAT group (n = 97). c, Association of the prevalence of cold-activated BAT and the season of birth in b. Warm birth group (n = 188), cold birth group (n = 168). d, Association of prevalence of cold-activated BAT and the season of fertilization in b. Warm fertilization group (n = 159), cold fertilization group (n = 197). e, Cold-induced BAT activity assessed as FDG uptake value (SUV) in c and d. f, BAT density (BAT-d) of the high and low BAT-d groups assessed as total haemoglobin concentration, [total Hb], in the supraclavicular region in Cohort 2. High BAT-d group (n = 143), low BAT-d group (n = 143). g, Association of the percentage of participants with high BAT-d and season of birth in f. Warm group (n = 144), cold birth group (n = 142). h, Association of the percentage of participants with high BAT-d and season of fertilization in f. Warm fertilization group (n = 153), cold fertilization group (n = 133). i, BAT-d assessed as [total Hb] in the supraclavicular region in g,h. Biologically independent samples (b–i). Number of participants (n) is indicated on the graph. Data are mean ± s.e.m.; two-tailed P values by unpaired Student’s t-test (b,e,f,i). Data are percentage; one-tailed P values by Fisher’s exact test (c,d,g,h).
