Regulation of uncoupling protein 2 expression by long-chain fatty acids and hormones in bovine mammary epithelial cells.
Although mammary epithelial cells are known to synthesize and accumulate triacylglycerol (TAG) in order to produce milk lipid in the cytosol, lipid and energy metabolism is still not fully understood. In this study, we assessed the effects of long-chain fatty acid (LCFA) on the accumulation of cytosolic TAG and uncoupling protein (UCP) 2 in cloned bovine mammary epithelial cells (bMEC). LCFAs significantly raised the expression of UCP2 mRNA and the accumulation of TAG. We observed the rapid elevation in UCP2 shown at 6h after LCFA treatment. Insulin (5-50 ng/ml) or dexamethasone (500 nM) significantly suppressed the expression of UCP2 mRNA. These results suggest that UCP2 play an important role of lipid and energy metabolism in mammary epithelial cells.
Yonezawa
Tomo
T
Department of Animal Physiology, Graduate School of Agricultural Science, Tohoku University, Amamiyamachi, Sendai 981-8555, Japan. yonet2301@yahoo.co.jp
Sanosaka
Masato
M
Haga
Satoshi
S
Kobayashi
Yosuke
Y
Katoh
Kazuo
K
Obara
Yoshiaki
Y
D000818:Animals; D002417:Cattle; D002478:Cells, Cultured; D003600:Cytosol / Q000187:drug effects / Q000378:metabolism; D003907:Dexamethasone / Q000378:metabolism* / Q000494:pharmacology; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism; D005227:Fatty Acids / Q000494:pharmacology / Q000502:physiology*; D007328:Insulin / Q000494:pharmacology / Q000502:physiology*; D007473:Ion Channels / Q000096:biosynthesis*; D008321:Mammary Glands, Animal / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D024101:Mitochondrial Proteins / Q000096:biosynthesis*; D012333:RNA, Messenger / Q000096:biosynthesis; D014280:Triglycerides / Q000378:metabolism*; D000071246:Uncoupling Protein 2
D005227:Fatty Acids; D007328:Insulin; D007473:Ion Channels; D024101:Mitochondrial Proteins; D012333:RNA, Messenger; D014280:Triglycerides; D000071246:Uncoupling Protein 2; D003907:Dexamethasone