+1 Recommend
0 collections
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      M3 Subtype of Muscarinic Acetylcholine Receptor Promotes Cardioprotection via the Suppression of miR-376b-5p

      Read this article at

          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.


          The M 3 subtype of muscarinic acetylcholine receptors (M 3-mAChR) plays a protective role in myocardial ischemia and microRNAs (miRNAs) participate in many cardiac pathophysiological processes, including ischemia-induced cardiac injury. However, the role of miRNAs in M 3-mAChR mediated cardioprotection remains unexplored. The present study was designed to identify miRNAs that are involved in cardioprotective effects of M 3-mAChR against myocardial ischemia and elucidate the underlying mechanisms. We established rat model of myocardial ischemia and performed miRNA microarray analysis to identify miRNAs involved in the cardioprotection of M 3-mAChR. In H9c2 cells, the viability, intracellular free Ca 2+ concentration ([Ca 2+]i), intracellular reactive oxygen species (ROS), miR-376b-5p expression level, brain derived neurophic factor (BDNF) and nuclear factor kappa-B (NF-κB) levels were measured. Our results demonstrated that M 3-mAChR protected myocardial ischemia injury. Microarray analysis and qRT-PCR revealed that miR-376b-5p was significantly up-regulated in ischemic heart tissue and the M 3-mAChRs agonist choline reversed its up-regulation. In vitro, miR-376b-5p promoted H 2O 2-induced H9c2 cell injuries measured by cells viability, [Ca 2+]i and ROS. Western blot and luciferase assay identified BDNF as a direct target of miR-376b-5p. M 3-mAChR activated NF-κB and thereby inhibited miR-376b-5p expression. Our data show that a novel M 3-mAChR/NF-κB/miR-376b-5p/BDNF axis plays an important role in modulating cardioprotection. MiR-376b-5p promotes myocardial ischemia injury possibly by inhibiting BDNF expression and M 3-mAChR provides cardioprotection at least partially mediated by the downregulation of miR-376b-5p through NF-κB. These findings provide new insight into the potential mechanism by which M 3-mAChR provides cardioprotection against myocardial ischemia injury.

          Related collections

          Most cited references 48

          • Record: found
          • Abstract: found
          • Article: not found

          NF-kappaB-dependent induction of microRNA miR-146, an inhibitor targeted to signaling proteins of innate immune responses.

          Activation of mammalian innate and acquired immune responses must be tightly regulated by elaborate mechanisms to control their onset and termination. MicroRNAs have been implicated as negative regulators controlling diverse biological processes at the level of posttranscriptional repression. Expression profiling of 200 microRNAs in human monocytes revealed that several of them (miR-146a/b, miR-132, and miR-155) are endotoxin-responsive genes. Analysis of miR-146a and miR-146b gene expression unveiled a pattern of induction in response to a variety of microbial components and proinflammatory cytokines. By means of promoter analysis, miR-146a was found to be a NF-kappaB-dependent gene. Importantly, miR-146a/b were predicted to base-pair with sequences in the 3' UTRs of the TNF receptor-associated factor 6 and IL-1 receptor-associated kinase 1 genes, and we found that these UTRs inhibit expression of a linked reporter gene. These genes encode two key adapter molecules downstream of Toll-like and cytokine receptors. Thus, we propose a role for miR-146 in control of Toll-like receptor and cytokine signaling through a negative feedback regulation loop involving down-regulation of IL-1 receptor-associated kinase 1 and TNF receptor-associated factor 6 protein levels.
            • Record: found
            • Abstract: found
            • Article: not found

            The muscle-specific microRNA miR-1 regulates cardiac arrhythmogenic potential by targeting GJA1 and KCNJ2.

            MicroRNAs (miRNAs) are endogenous noncoding RNAs, about 22 nucleotides in length, that mediate post-transcriptional gene silencing by annealing to inexactly complementary sequences in the 3'-untranslated regions of target mRNAs. Our current understanding of the functions of miRNAs relies mainly on their tissue-specific or developmental stage-dependent expression and their evolutionary conservation, and therefore is primarily limited to their involvement in developmental regulation and oncogenesis. Of more than 300 miRNAs that have been identified, miR-1 and miR-133 are considered to be muscle specific. Here we show that miR-1 is overexpressed in individuals with coronary artery disease, and that when overexpressed in normal or infarcted rat hearts, it exacerbates arrhythmogenesis. Elimination of miR-1 by an antisense inhibitor in infarcted rat hearts relieved arrhythmogenesis. miR-1 overexpression slowed conduction and depolarized the cytoplasmic membrane by post-transcriptionally repressing KCNJ2 (which encodes the K(+) channel subunit Kir2.1) and GJA1 (which encodes connexin 43), and this likely accounts at least in part for its arrhythmogenic potential. Thus, miR-1 may have important pathophysiological functions in the heart, and is a potential antiarrhythmic target.
              • Record: found
              • Abstract: found
              • Article: not found

              Induction and regulatory function of miR-9 in human monocytes and neutrophils exposed to proinflammatory signals.

              Inflammation involves a coordinated, sequential, and self limiting sequence of events controlled by positive and negative regulatory mechanisms. Recent studies have shown that microRNAs (miRNAs), an evolutionarily conserved class of endogenous 22-nucleotide noncoding RNAs, contribute to the regulation of inflammation by repressing gene expression at the posttranscriptional level. In this study, we characterize the profile of miRNAs induced by LPS in human polymorphonuclear neutrophils (PMN) and monocytes. In particular, we identify miR-9 as the only miRNA (among 365 analyzed) up-regulated in both cell types after TLR4 activation. miR-9 is also induced by TLR2 and TLR7/8 agonists and by the proinflammatory cytokines TNF-alpha and IL-1beta, but not by IFNgamma. Among the 3 different genes encoding miR-9 precursors in humans, we show that LPS selectively induces the transcription of miR-9-1 located in the CROC4 locus, in a MyD88- and NF-kappaB-dependent manner. In PMN and monocytes, LPS regulates NFKB1 at both the transcriptional and posttranscriptional levels, and a conserved miR-9 seed sustained a miR-9-dependent inhibition of the NFKB1 transcript. Overall, these data suggest that TLR4-activated NF-kappaB rapidly increases the expression of miR-9 that operates a feedback control of the NF-kappaB-dependent responses by fine tuning the expression of a key member of the NF-kappaB family.

                Author and article information

                Role: Editor
                PLoS One
                PLoS ONE
                Public Library of Science (San Francisco, USA )
                2 March 2012
                : 7
                : 3
                [1 ]Department of Pharmacology, the State-Province Key Laboratories of Biomedicine-Pharmaceutics of China, Key Laboratory of Cardiovascular Research, Ministry of Education, Harbin Medical University, Harbin, Heilongjiang, People′s Republic of China
                [2 ]Department of Anesthesiology of the Second Affiliated Hospital, Harbin Medical University, Harbin, Heilongjiang, People′s Republic of China
                [3 ]Institute of Clinical Pharmacology of the Second Affiliated Hospital, Harbin Medical University, Harbin, Heilongjiang, People′s Republic of China
                University of Oldenburg, Germany
                Author notes

                Conceived and designed the experiments: YL ZD. Performed the experiments: ZP KF HZ YF JX FG YG HQ YH SW YZ NW RH. Analyzed the data: ZP YH YG YL. Wrote the paper: ZP YG YL.

                Pan et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
                Pages: 8
                Research Article
                Model Organisms
                Animal Models
                Molecular Cell Biology
                Signal Transduction
                Chemical Biology



                Comment on this article