Premium
Thyoid hormone receptor alfa (TRa) activation plays an important role in BAT adaptative thermogenesis
Author(s) -
Farah Livia Xavier Soares,
Nassif Renata Jorge,
Scanlan Thomas,
Ribeiro Miriam Oliveira
Publication year - 2011
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.25.1_supplement.624.6
Cold‐induced thermogenesis is produced primarily in brown adipose tissue (BAT) and it is stimulated by the sympathetic nervous system, but has an absolute requirement for thyroid hormone. TRB activation increases UCP‐1 synthesis but does not restore the impaired thermogenesis in hypothyroidism. In this study we used a new TR‐alfa analog, CO‐23, to determine the role of TRalfa in adaptive thermogenesis. Hypothyroid mice were treated for 10 days with T3 (30 ng/g BW) or CO‐23 (27ng/g BW). The BAT in euthyroid mice showed a 2.0°C elevation upon infusion of NE but the temperature did not increase in hypothyroid mice(<0.5°C). CO‐23 partially corrected the interscapular BAT thermogenesis (1.5±0.28°C). When exposed to 4°C, CO‐23 and T3 treated mice kept their body temperature (37.0±1.7°C and 36.1±1.9°C, respectively) but hypothyroid mice went to severe hypothermia (32.7±3,2 vs.ctrl 37.4±1.1, p<0,001). Interestingly, CO‐23 did not altered the heart weight as T3 (ctrl 6.76±0.5; Hypo 6.5±0.9; CO‐23 7.5±0.6mg/g BW vs. T3 10.1±0.9mg/g BW, p<0.05). Our data indicates that TRalfa activation is important in BAT thermogenesis and also that this receptor plays an important role in body temperature regulation.