Horm Metab Res 2017; 49(08): 625-630
DOI: 10.1055/s-0043-109563
Endocrine Research
© Georg Thieme Verlag KG Stuttgart · New York

Human Epicardial Fat Expresses Glucagon-Like Peptide 1 and 2 Receptors Genes

Gianluca Iacobellis
1   Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Miami Miller School of Medicine, Miami, USA
,
Vladimir Camarena
2   John P. Hussman Institute for Human Genomics, Dr. John T. Macdonald Foundation Department of Human Genetics, University of Miami Miller School of Medicine, Miami, USA
,
David W. Sant
2   John P. Hussman Institute for Human Genomics, Dr. John T. Macdonald Foundation Department of Human Genetics, University of Miami Miller School of Medicine, Miami, USA
,
Gaofeng Wang
2   John P. Hussman Institute for Human Genomics, Dr. John T. Macdonald Foundation Department of Human Genetics, University of Miami Miller School of Medicine, Miami, USA
› Author Affiliations
Further Information

Publication History

received 10 December 2016

accepted 19 April 2017

Publication Date:
17 May 2017 (online)

Abstract

Epicardial adipose tissue (EAT) is an easily measurable visceral fat of the heart with unique anatomy, functionality, and transcriptome. EAT can serve as a therapeutic target for pharmaceutical agents targeting the fat. Glucagon-like peptide-1 (GLP-1) and GLP-2 analogues are newer drugs showing beneficial cardiovascular and metabolic effects. Whether EAT expresses GLP- 1 and 2 receptors (GLP-1R and GLP-2R) is unknown. RNA-seq analysis and quantitative real-time polymerase chain reaction (qRT-PCR) were performed to evaluate the presence of GLP-1R and GLP-2R in EAT and subcutaneous fat (SAT) obtained from 8 subjects with coronary artery disease and type 2 diabetes mellitus undergoing elective cardiac surgery. Immunofluorescence was also performed on EAT and SAT samples using Mab3f52 against GLP-1R. Our RNA-sequencing (RNA-seq) analysis showed that EAT expresses both GLP-1R and GLP-2R genes. qRT-PCR analysis confirmed that GLP-1R expression was low but detected by 2 different sets of intron-spanning primers. GLP-2R expression was detected in all patients and was found to be 5-fold higher than GLP-1R. The combination of accurately spliced reads from RNA-seq and successful amplification using intron-spanning primers indicates that both GLP-1R and GLP-2R are expressed in EAT. Immunofluorescence clearly showed that GLP-1R is present and more abundant in EAT than SAT. This is the first time that human EAT is found to express both GLP-1R and GLP-2R genes. Pharmacologically targeting EAT may induce beneficial cardiovascular and metabolic effects.

 
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