Altered protein expression and phosphorylation from retroperitoneal adipose tissue of ovariectomy rats.xlsx

Menopause is
often accompanied by visceral obesity. With the aim of exploring the
consequences of ovarian failure on visceral fat, we evaluated the effects of
ovariectomy and estrogen replacement on the proteome/phosphoproteome and on the
fatty acids profile of the retroperitoneal adipose depot (RAT) of rats.
Eighteen three months old female Wistar rats were either ovariectomized or
sham-operated and fed with standard chow for three months. A sub-group of
ovariectomized rats received estradiol replacement. RAT samples were analyzed
using data-independent acquisitions LC-MS/MS and pathway analysis was performed
with the differentially expressed/phosphorylated proteins. RAT lipid profile
was analyzed by gas chromatography.

Ovariectomy induced high adiposity and insulin
resistance and promoted alterations in protein expression and phosphorylation. Pathway analysis showed that 5 pathways were significantly affected by
ovariectomy, namely metabolism of lipids (included fatty acid metabolism and
mitochondrial fatty acid β-oxidation), fatty acyl-CoA biosynthesis, innate
immune system (included neutrophil degranulation), metabolism of vitamins and
cofactors, and integration of energy metabolism (included ChREBP activates
metabolic gene expression). Lipid profile analysis showed increased palmitic
and palmitoleic acids content. The analysis of the data indicated that ovariectomy favored lipogenesis while it impaired
fatty acids oxidation, and induced a pro-inflammatory state in the visceral
adipose tissue. These effects are consistent with the findings of high
adiposity, hyperleptinemia, and impaired insulin sensitivity. The observed
alterations were partially attenuated by estradiol replacement. The data point
to a role of disrupted lipid metabolism in adipose tissue in the genesis of
obesity after menopause.