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Adipose hypothermia in obesity and its association with period homolog 1, insulin sensitivity, and inflammation in fat.

Adipose hypothermia in obesity and its association with period homolog 1, insulin sensitivity, and inflammation in fat.

Authors :
Masaya Yamaoka
Norikazu Maeda
Yasunori Takayama
Ryohei Sekimoto
Yu Tsushima
Keisuke Matsuda
Takuya Mori
Kana Inoue
Hitoshi Nishizawa
Makoto Tominaga
Tohru Funahashi
Iichiro Shimomura
Source :
PLoS ONE, Vol 9, Iss 11, p e112813 (2014)
Publication Year :
2014
Publisher :
Public Library of Science (PLoS), 2014.

Abstract

Visceral fat adiposity plays an important role in the development of metabolic syndrome. We reported previously the impact of human visceral fat adiposity on gene expression profile of peripheral blood cells. Genes related to circadian rhythm were highly associated with visceral fat area and period homolog 1 (PER1) showed the most significant negative correlation with visceral fat area. However, regulation of adipose Per1 remains poorly understood. The present study was designed to understand the regulation of Per1 in adipose tissues. Adipose Per1 mRNA levels of ob/ob mice were markedly low at 25 and 35 weeks of age. The levels of other core clock genes of white adipose tissues were also low in ob/ob mice at 25 and 35 weeks of age. Per1 mRNA was mainly expressed in the mature adipocyte fraction (MAF) and it was significantly low in MAF of ob/ob mice. To examine the possible mechanisms, 3T3-L1 adipocytes were treated with H2O2, tumor necrosis factor-α (TNF-α), S100A8, and lipopolysaccharide (LPS). However, no significant changes in Per1 mRNA level were observed by these agents. Exposure of cultured 3T3-L1 adipocytes to low temperature (33°C) decreased Per1 and catalase, and increased monocyte chemoattractant protein-1 (Mcp-1) mRNA levels. Hypothermia also worsened insulin-mediated Akt phosphorylation in 3T3-L1 adipocytes. Finally, telemetric analysis showed low temperature of adipose tissues in ob/ob mice. In obesity, adipose hypothermia seems to accelerate adipocyte dysfunction.

Subjects

Subjects :
Medicine
Science

Details

Language :
English
ISSN :
19326203
Volume :
9
Issue :
11
Database :
Directory of Open Access Journals
Journal :
PLoS ONE
Publication Type :
Academic Journal
Accession number :
edsdoj.867d27d1132947d8862fee1e4de78586
Document Type :
article
Full Text :
https://doi.org/10.1371/journal.pone.0112813