Abstract
Context and Objective
Adipose tissue in insulin resistant subjects contains inflammatory cells and extracellular matrix components. This study examined adipose pathology of insulin resistant subjects who were treated with pioglitazone or fish oil.
Design, Setting and Participants
Adipose biopsies were examined from nine insulin resistant subjects before/after treatment with pioglitazone 45 mg/day for 12 weeks and also from 19 subjects who were treated with fish oil (1,860 mg EPA, 1,500 mg DHA daily). These studies were performed in a clinical research center setting.
Results
Pioglitazone treatment increased the cross-sectional area of adipocytes by 18% (p = 0.01), and also increased capillary density without affecting larger vessels. Pioglitazone treatment decreased total adipose macrophage number by 26%, with a 56% decrease in M1 macrophages and an increase in M2 macrophages. Mast cells were more abundant in obese versus lean subjects, and were decreased from 24 to 13 cells/mm(2) (p = 0.02) in patients treated with pioglitazone, but not in subjects treated with FO. Although there were no changes in total collagen protein, pioglitazone increased the amount of elastin protein in adipose by 6-fold.
Conclusion
The PPARγ agonist pioglitazone increased adipocyte size yet improved other features of adipose, increasing capillary number and reducing mast cells and inflammatory macrophages. The increase in elastin may better permit adipocyte expansion without triggering cell necrosis and an inflammatory reaction.
Document Type
Article
Publication Date
7-10-2014
Digital Object Identifier (DOI)
http://dx.doi.org/10.1371/journal.pone.0102190
Repository Citation
Spencer, Michael L.; Yang, Lin; Adu, Akosua; Finlin, Brian S.; Zhu, Beibei; Shipp, Lindsey Rae; Rasouli, Neda; Peterson, Charlotte A.; and Kern, Philip A., "Pioglitazone Treatment Reduces Adipose Tissue Inflammation Through Reduction of Mast Cell and Macrophage Number and by Improving Vascularity" (2014). Internal Medicine Faculty Publications. 35.
https://uknowledge.uky.edu/internalmedicine_facpub/35
Bivariate comparison of manual measurements of cross-sectional area to automated measurement of cross-sectional area.
Figure_S2.tif (231 kB)
Figure S2.
Methods_S1.docx (29 kB)
Methods S1.
Notes/Citation Information
Published in PLOS One, v. 9, issue. 7, e102190.
© 2014 Spencer et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.