Figure 6
In vivo application of Fgf8b into epididymal white adipose. Implantation of pellets releasing 100 ng FGF8b per day and placebo pellets into the epididymal white adipose tissue results in a brownish aureole around the implantation site of FGF8b, but not of placebo pellets after three weeks of treatment. (A) Photographs of epididymal depots from three independent experiments of 6 mice each. (B) Visual browning score on a scale of 1 (least) to 10 (most) browning around a pellet was assessed by six blinded observers. Each dot represents the mean value for one specific depot, n = 18, p = 0.0068 (t test). (C) Visual browning assessment by keywords describing multilocular adipocyte occurrence and UCP1 immunostaining on histological sections was assessed by six blinded observers. Data is provided as percentage of 30 sections per depots that fit the keyword description. Each dot represents the mean value for one specific depot; no significant differences (Holm-Sidak multiple test). (E) Indirect calorimetry and injection of norepinephrine did not reveal a difference in maximal thermogenic capacity in Fgf8b versus placebo treated mice. (D) Transcript abundance of brite adipocyte markers genes was not markedly increased. Ucp1, uncoupling protein 1; Cidea, cell death-inducing DNA fragmentation factor alpha-like effector A; cox7a1, cytochrome c oxidase subunit 7A1; otop1, otopetrin 1; Tmem26, Transmembrane protein 26; Tbx1, T-box transcription factor 1; Cd137, cluster of differentiation 137; Hoxc9, homeobox C9; Shox2, Short stature homeobox 2; Slc27a1, Long-chain fatty acid transport protein 1; n = 5; no significant differences (Holm-Sidak multiple test).
