Adipose tissue becomes dysfunctional in the setting of obesity, and contributes significantly to the development of insulin resistance and other features of metabolic syndrome. A large part of this is believed to result from inflammation and fibrosis. Although fibrosis has been extensively studied in other tissues, adipose tissue fibrosis is still unexplored. We have generated preliminary data that that high fat feeding alters the transcriptional and epigenomic state of mature adipocytes, reducing adipogenic gene expression and promoting the elaboration of a fibrogenic milieu usually associated with myofibroblasts. Furthermore, our data suggest a role for the transcription factors Smad3 and SRF in this process. In this application, we will use a combination of murine and human cell culture models as well as in vivo studies in mice to interrogate the role of TGF? in adipose fibrosis, focusing on the relative contributions of two downstream transcriptional effectors: the traditional Smad2/3/4 pathway typically associated with TGF??mediated signaling, as well as SRF. We will focus on events that lead to reduced PPAR? action and also events that promote fibrosis, assessing how much these different outcomes influence one another. Our objective is to deconvolute the complex transcriptional events that promote adipose fibrosis and to establish whether these pathways are tractable to therapeutic intervention.

Public Health Relevance

Adipose tissue becomes dysfunctional in obesity, in large part due to excess inflammation and fibrosis. The mechanisms that underlie fibrotic change in adipocytes are not understood. Our data suggests that mature adipocytes take on a new identity in the setting of overnutrition in which fibrosis is induced; in this application we will dissect the mechanisms that drive this change.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Research Project (R01)
Project #
5R01DK113669-02
Application #
9444426
Study Section
Cellular Aspects of Diabetes and Obesity Study Section (CADO)
Program Officer
Haft, Carol R
Project Start
2017-03-01
Project End
2021-02-28
Budget Start
2018-03-01
Budget End
2019-02-28
Support Year
2
Fiscal Year
2018
Total Cost
Indirect Cost
Name
Beth Israel Deaconess Medical Center
Department
Type
DUNS #
071723621
City
Boston
State
MA
Country
United States
Zip Code
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