The role of receptor-interacting protein 140 in the accumulation of fat in ovariectomised rats.
BACKGROUND
Receptor-interacting protein 140 (RIP140) is a corepressor for nuclear receptors with an important role in the inhibition of energy expenditure. Postmenopausal women have increased white adipose tissue (WAT), and excessive accumulation of adipose tissue (obesity) implies a health risk. The aim of the present work was to investigate the time course of RIP140 expression in WAT during the development of ovariectomy (OVX)-induced obesity in rats.


METHODS
OVX was performed in female Sprague-Dawley (SD) rats 8 weeks old. Body weight and food intake were determined once a week. WAT of sham-operated, OVX and OVX plus 17β-estradiol therapy (OVX/E2) female SD rats was weighed and used to analyse RIP140 and uncoupling protein 1 (UCP-1) expression by Western blot.


RESULTS
Food intake and body weight were significantly increased during the 2-8 weeks after OVX. Even though body weight increased until killing, food intake progressively decreased from 9 to 16 weeks after OVX in rats. Meanwhile, increased WAT mass and decreased RIP140 expression in WAT were observed in OVX rats. In contrast, the expression of UCP-1, a key target gene of RIP140, in WAT of OVX rats was significantly higher than in sham-operated rats. All of these alterations caused by OVX were mostly reversed by the replacement of 17β-estradiol.


CONCLUSIONS
The down-regulation of RIP140 in WAT may play a compensatory role in OVX-induced obesity in rat.
Liu
Won-Hsiung
WH
Department of Pediatrics, Chi-Mei Foundation Hospital, Tainan, Taiwan.
Lee
Yen-Mei
YM
Lam
Kwok-Keung
KK
Chen
Yuh-Fung
YF
Wang
Jhi-Joung
JJ
Yen
Mao-Hsiung
MH
Cheng
Pao-Yun
PY
D048868:Adaptor Proteins, Signal Transducing / Q000096:biosynthesis*; D052436:Adipose Tissue, White / Q000378:metabolism*; D050154:Adiposity / Q000502:physiology*; D000818:Animals; D001069:Appetite Regulation / Q000502:physiology; D015153:Blotting, Western; D001835:Body Weight; D015536:Down-Regulation; D004435:Eating; D004958:Estradiol / Q000008:administration & dosage / Q000378:metabolism; D004967:Estrogens / Q000008:administration & dosage / Q000378:metabolism; D005260:Female; D007473:Ion Channels / Q000096:biosynthesis; D008593:Menopause / Q000378:metabolism*; D024101:Mitochondrial Proteins / Q000096:biosynthesis; D009687:Nuclear Proteins / Q000096:biosynthesis*; D000078723:Nuclear Receptor Interacting Protein 1; D009765:Obesity / Q000378:metabolism*; D010052:Ovariectomy; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors; D000071256:Uncoupling Protein 1
D048868:Adaptor Proteins, Signal Transducing; D004967:Estrogens; D007473:Ion Channels; D024101:Mitochondrial Proteins; D009687:Nuclear Proteins; D000078723:Nuclear Receptor Interacting Protein 1; C000604373:Ucp1 protein, rat; D000071256:Uncoupling Protein 1; D004958:Estradiol