Dynamic Changes in Lipid Droplet-Associated Proteins in the "Browning" of White Adipose Tissues
File(s)
Accepted version
Author(s)
Barneda, D
Frontini, A
Cinti, S
Christian, M
Type
Journal Article
Abstract
The morphological and functional differences between lipid droplets (LDs) in brown (BAT) and white (WAT) adipose tissue will largely be determined by their associated proteins. Analysing mRNA expression in mice fat depots we have found that most LD protein genes are expressed at higher levels in BAT, with the greatest differences observed for Cidea and Plin5. Prolonged cold exposure, which induces the appearance of brown-like adipocytes in mice WAT depots, was accompanied with the potentiation of the lipolytic machinery, with changes in ATGL, CGI-58 and G0S2 gene expression. However the major change detected in WAT was the enhancement of Cidea mRNA. Together with the increase in Cidec, it indicates that LD enlargement through LD-LD transference of fat is an important process during WAT browning. To study the dynamics of this phenotypic change, we have applied 4D confocal microscopy in differentiated 3T3-L1 cells under sustained beta-adrenergic stimulation. Under these conditions the cells experienced a LD remodelling cycle, with progressive reduction on the LD size by lipolysis, followed by the formation of new LDs, which were subjected to an enlargement process, likely to be CIDE-triggered, until the cell returned to the basal state. This transformation would be triggered by the activation of a thermogenic futile cycle of lipolysis/lipogenesis and could facilitate the molecular mechanism for the unilocular to multilocular transformation during WAT browning.
Date Issued
2013
Citation
Biochim Biophys Acta, 2013
ISSN
0006-3002
Journal / Book Title
Biochim Biophys Acta
Copyright Statement
© 2013 Elsevier B.V. All rights reserved. NOTICE: this is the author’s version of a work that was accepted for publication in Biochimica et Biophysica (BBA) - Molecular and cell biology of Lipids. The publication is In Press. A definitive version will be published in BIOCHIMICA ET BIOPHYSICA (BBA) - MOLECULAR AND CELL BIOLOGY OF LIPIDS (2013)] DOI: http://dx.doi.org/10.1016/j.bbalip.2013.01.015
Description
08.02.13 KB. Accepted version ok to add to Spiral. Elsevier ok while mandate is not enforced.
Identifier
http://www.ncbi.nlm.nih.gov/pubmed/23376222
Notes
Barneda, David Frontini, Andrea Cinti, Saverio Christian, Mark Biochim Biophys Acta. 2013 Jan 30. pii: S1388-1981(13)00034-6. doi: 10.1016/j.bbalip.2013.01.015. The morphological and functional differences between lipid droplets (LDs) in brown (BAT) and white (WAT) adipose tissue will largely be determined by their associated proteins. Analysing mRNA expression in mice fat depots we have found that most LD protein genes are expressed at higher levels in BAT, with the greatest differences observed for Cidea and Plin5. Prolonged cold exposure, which induces the appearance of brown-like adipocytes in mice WAT depots, was accompanied with the potentiation of the lipolytic machinery, with changes in ATGL, CGI-58 and G0S2 gene expression. However the major change detected in WAT was the enhancement of Cidea mRNA. Together with the increase in Cidec, it indicates that LD enlargement through LD-LD transference of fat is an important process during WAT browning. To study the dynamics of this phenotypic change, we have applied 4D confocal microscopy in differentiated 3T3-L1 cells under sustained beta-adrenergic stimulation. Under these conditions the cells experienced a LD remodelling cycle, with progressive reduction on the LD size by lipolysis, followed by the formation of new LDs, which were subjected to an enlargement process, likely to be CIDE-triggered, until the cell returned to the basal state. This transformation would be triggered by the activation of a thermogenic futile cycle of lipolysis/lipogenesis and could facilitate the molecular mechanism for the unilocular to multilocular transformation during WAT browning.