Trichostatin A induces a unique set of microRNAs including miR-129-5p that blocks cyclin-dependent kinase 6 expression and proliferation in H9c2 cardiac myocytes

Abstract

The pan-histone deacetylase inhibitor (HDACI), trichostatin A (TSA), was shown to normalize interleukin-18-induced cardiac hypertrophy in vivo and in vitro; evidently, this occurred via epigenetic mechanisms that profoundly altered cardiac gene expression (Majumdar et al. in, Physiol Genom, 43: 1392, 2011; BMC Genom, 13: 709, 2012). Here, we tested the hypothesis that TSA-induced changes in chromatin architecture also led to altered expression of microRNAs that in turn, contributed to the unique transcriptome of cardiac myocytes exposed to the HDACI. Using miRCURY LNA™ Universal microRNA PCR system, we demonstrate that H9c2 cells exposed to TSA for 6 and 24 h elicited differential expression of 19 and 16 microRNAs, respectively. H9c2 cells incubated in medium-containing 100 nM of TSA elicited a rapid and robust induction of miR-129-5p. Enhanced expression of miR-129-5p was also observed in the hearts of TSA-treated mice. Induction of miR-129-5p in H9c2 cells was accompanied by reduced expression of its direct target, cyclin-dependent kinase 6 (CDK6) that is a key regulator of cell cycle. Using cell division-dependent dilution of Cell Trace™ violet measurements we showed that concomitant induction of miR-129-5p and reduced CDK6 expression were mechanistically involved in TSA-induced inhibition of proliferation of H9c2 cells. Consistent with this scenario, cells expressing an antagomiR of miR-129-5p were resistant to the anti-proliferative actions of TSA. These data indicate that although TSA treatment led to altered expression of several microRNAs, the overarching action of TSA (i.e., inhibition of cell division) in H9c2 cells was achieved via miR-129-5p.

MiR‐129‐5p alleviates myocardial injury by targeting suppressor of cytokine signaling 2 after ischemia/reperfusion

“…Gipsy et al first found that miR-129-5p modulate the proliferation of cardiac myocytes by targeting cyclin-dependent kinase 6. 24 Then miR-129-5p was found to restrain endothelial cell autophagy in mouse atherosclerosis model, implying its potential role in atherosclerosis progression. 25 MiR-129-5p also promotes revascularization in rat intracerebral hemorrhage model, and alleviates brain injury induced by hypoxic/ischemic in mice.…”

“…Recent studies disclosed its emerging role in the pathogenesis of heart diseases, which inspired us to carry out the present study. Gipsy et al first found that miR‐129‐5p modulate the proliferation of cardiac myocytes by targeting cyclin‐dependent kinase 6 24 . Then miR‐129‐5p was found to restrain endothelial cell autophagy in mouse atherosclerosis model, implying its potential role in atherosclerosis progression 25 .…”

Involvement of TRPC1 in Nampt-induced cardiomyocyte hypertrophy through the activation of ER stress

“…H9c2 cells were obtained from American Type and Culture Collection (ATCC) and cultured in high glucose DMEM containing 10% fetal bovine serum (FBS, BI, Israel) and 100U/ml penicillin-streptomycin (13). The cells were grown on P60 plates with 2ml medium in the incubator at 37℃ under an environment of 5% CO 2 .…”

Endocardial HDAC3 is required for myocardial trabeculation

“…miR-129-5p plays important roles in cancer by either promoting or inhibiting tumorigenesis through regulating a variety of downstream targets and pathways 61, 62 . Several studies have shown that miR-129-5p protects adult hearts from ischemia/reperfusion injuries 63, 64 , while another study demonstrated that treating cultured H9c2 cardiomyocytes with HDAC pan-inhibitor Trichostatin A results in decreased cardiomyocyte proliferation with enhanced miR-129-5p expression 65 . This is consistent with our current findings in the developing endocardium (Figure 4).…”