Abstract 15088: RNA-Seq Reveals New Insights Into the Protective Role of ANGPTL4 Against Mouse Myocardial Ischemia/ Reperfusion Injury
Introduction: Angiopoietin-like protein 4 (ANGPTL4) is a dual-function protein: an inhibitor of lipoprotein and hepatic lipases with angiogenic properties. Its E40K mutation is associated with an increased risk of CAD. The aim of this study is to investigate the role of Angptl4 in mouse myocardial ischemia/ reperfusion injury (IRI) using wild type (Angptl4+/+) or Angptl4 deficient (Angptl4+/-) mice and to apply state of art next generation sequencing, RNA-seq, to profile transcriptomic insights into the underlying molecular mechanisms.
Methods: C57BL/6J male and female wild type (Angptl4+/+) and Angptl4 deficient (Angptl4+/-) mice (8-12 weeks) were subjected to either sham or myocardial ischemia by a 40 min occlusion of the left anterior descending coronary artery followed by 3 h reperfusion. Mouse hearts and sera were harvested for assessing infarct size and area at risk, apoptosis and profiling transcriptome by RNA-seq using Illumina’s HiSeq1500 next generation DNA sequencing instrument.
Results: The size of myocardial infarction/area at risk was 2.75-fold smaller in Angptl4+/+ mice (15.78±9.55) than in Angptl4+/- mice(43.45±11.58, n≥4/ per group, p<0.01). TUNEL, serum creatine kinase and LDH assays indicated significantly less myocardial apoptosis and injury in Angptl4+/+ mice. RNA-seq revealed differential expressions of 1151- ( ≥ 2 fold) and 2252- gene transcripts (≤ 2 fold,) in mouse IRI heart tissue (Angptl4+/- vs (Angptl4+/+). These differentially expressed gene transcripts are involved in a number of canonical and unexplored pathways such as cell death and survival, acute phase response signaling, IL-10 signaling, Erb B signaling, guanosine nucleotide degradation III. This list also contains many novel gene isoforms. Among them, three isoforms of major urinary protein (Mup2, 7 and 15) were the highest upregulated gene transcripts (>1000 folds). They may contribute to the free radical production and thus cause more severe injury in mouse IRI in Angptl4+/- mice. MUP’s relevance to heart IRI is unexplored before.
Conclusion: Our results support a protective role of Angptl4 in mice IRI and Mup isoform 2, 7 and 15 may prove to be novel targets for therapeutic intervention in heart IRI.
- © 2013 by American Heart Association, Inc.