Rosiglitazone-induced PPARγ activation promotes intramuscular adipocyte adipogenesis of pig

Abstract

Intramuscular fat (IMF) positively influences various aspects of meat quality, while the subcutaneous fat (SF) has negative effect on carcass characteristics and fattening efficiency. Peroxisome proliferator-activated receptor gamma (PPARγ) is a key regulator of adipocyte differentiation, herein, through bioinformatic screen for the potential regulators of adipogenesis from two independent microarray datasets, we identified that PPARγ is a potentially regulator between porcine IMF and SF adipogenesis. Then we treated subcutaneous preadipocytes (SA) and intramuscular preadipocytes (IMA) of pig with RSG (1 µmol/L), and we found that RSG treatment promoted the differentiation of IMA via differentially activating PPARγ transcriptional activity. Besides, RSG treatment promoted apoptosis and lipolysis of SA. Meanwhile, by the treatment of conditioned medium, we excluded the possibility of indirect regulation of RSG from myocyte to adipocyte and proposed that AMPK may mediate the RSG-induced differential activation of PPARγ. Collectively, the RSG treatment promotes IMA adipogenesis, and advances SA lipolysis, this effect may be associated with AMPK-mediated PPARγ differential activation. Our data indicates that targeting PPARγ might be an effective strategy to promote intramuscular fat deposition while reduce subcutaneous fat mass of pig.

GRAPHICAL ABSTRACT

RSG-induced PPARγ activation promotes intramuscular adipogenesis of pig in vitro. RSG treatment promotes the apoptosis and lipolysis of SA while it promotes adipogenesis of IMA via AMPK-mediated differential activation of PPARγ.

Keywords:

• Pig
• rosiglitazone
• PPARγ
• subcutaneous preadipocyte
• intramuscular preadipocyte

Acknowledgements

We thank others on Li’s team and Shi’s team for the powerful supports throughout the whole experiment.

Authors’ contributions

Youlei Li, Zhaolu Wang, Xin’e Shi and Xiao Li conceived the work; Youlei Li and Zhaolu Wang performed the experiment and statistical analyses. Zhaolu Wang, Lingling Wu and Yuan Guo drafted the manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The authors gratefully acknowledge the financial supports from the Scientific and Technological Innovation Project for Youths of Northwest A&F University [grant number 2452019205] and the National Basic Research Program of China [grant number 2015CB943102].