Abstract 18773: Discovery and Translation of Novel Long Intergenic Non-Coding RNAs in Inflammatory Cardio-Metabolic Disorders
Objective: The purpose of this study is to identify long intergenic non-coding RNAs (LincRNAs) modulated by inflammation utilizing human experimental endotoxemia and to explore their association with cardiometabolic traits.
Methods and results: We performed deep high-throughput RNAseq (~500 million reads per sample) in adipose tissue and whole blood of a healthy subject before and after endotoxin (LPS 1 ng/Kg) administration. Of 8,179 LincRNAs identified by Cabili et al (Gene & Development 2011. 25:1915-1927), we detected 514 present in adipose and 266 in blood, with 69 (13.6%) and 56 (21.2%) LincRNAs respectively modulated by LPS with just six LPS-modulated lincRNAs overlapping in both tissues. In both tissues, LincRNAs had lower expression and more tissue specificity than protein coding RNAs. RNAseq of adipose and blood in 2 additional individuals during endotoxemia was used to confirm findings and qPCR used to validate top findings in an additional 7 study participants. Linc-ARFIP1-4 and Linc-CMC1-2 were consistently reduced by LPS in blood, but not in adipose. Interestingly, Linc-DMRT2 and Linc-TP53I13, the top adipose LPS-modulated LincRNA, was more abundant in human primary adipocytes than monocyte and macrophage cultured in vitro while adipose samples obtained from obese subjects exhibited lower Linc-DMRT2 and Linc-TP63I13 expression (77% and 50% lower respectively, P<0.05) compared to lean individuals (N=10/group). To further investigate biological roles, we generated lentiviral-vectors with short hairpin RNAs (shRNAs) targeting Linc-DMRT2 and Linc-TP53I13 as well as Linc-AQPEP, the top expressed adipose-specific LincRNA. Preliminary studies demonstrated more than 50% knockdown of these lincRNAs in human adipocytes with shRNA application and functional studies are ongoing to characterize their impact on adipocyte differentiation, lipid storage and insulin sensitivity.
Conclusion: These novel data from a human endotoxemia experiment suggest that inflammatory modulation of adipose LincRNAs might modulate adipose functions in cardio-metabolic disorders.
- © 2013 by American Heart Association, Inc.