Muscle Cell News Volume 2.08 | Mar 13 2017

TOP STORY

Estrogens Enhance Myoblast Differentiation in Facioscapulohumeral Muscular Dystrophy by Antagonizing DUX4 Activity

The authors utilized myoblasts isolated from facioscapulohumeral muscular dystrophy (FSHD) patients (FSHD myoblasts) to investigate the effect of estrogens on muscle properties. Their results demonstrated that estrogens counteract the differentiation impairment of FSHD myoblasts without affecting cell proliferation or survival. [J Clin Invest] Full Article

(Ranked by impact factor of the journal)

CARDIAC MUSCLE CELLS

Sfrp5 Identifies Murine Cardiac Progenitors for All Myocardial Structures Except for the Right Ventricle

Scientists showed that the expression of secreted frizzled-related protein Sfrp5 in the mouse identifies common progenitors for the outflow tract, left ventricle, atrium and sinus venosus but not the right ventricle. [Nat Commun] Full Article

DDiT4L Promotes Autophagy and Inhibits Pathological Cardiac Hypertrophy in Response to Stress

Researchers found that the transcript encoding DNA damage–inducible transcript 4-like (DDiT4L) was expressed in murine models of pathological cardiac hypertrophy but not in those of physiological cardiac hypertrophy. In cardiomyocytes, DDiT4L localized to early endosomes and promoted stress-induced autophagy through a process involving mechanistic target of rapamycin complex 1 (mTORC1). Exposing cardiomyocytes to various types of pathological stress increased the abundance of DDiT4L, which inhibited mTORC1 but activated mTORC2 signaling. [Sci Signal] Full Article

Three-Dimensional Cardiac Microtissues Composed of Cardiomyocytes and Endothelial Cells Co-Differentiated from Human Pluripotent Stem Cells

Robust and predictive cardiac disease models that faithfully recapitulate native human physiology in vitro would ideally incorporate cardiomyocyte-endothelium crosstalk. Scientists generated and characterized human cardiac microtissues in vitro that integrate both cell types in complex 3D structures. They established conditions for simultaneous differentiation of cardiomyocytes and endothelial cells from human pluripotent stem cells following initial cardiac mesoderm induction. [Development] Full Article

Accurate Nanoelectrode Recording of Human Pluripotent Stem Cell-Derived Cardiomyocytes for Assaying Drugs and Modeling Disease

Researchers validated the use of nanopillar electrodes for myriad further applications of human pluripotent stem cell-derived cardiomyocytes such as cardiomyocyte maturation monitoring and electrophysiology-contractile force correlation. [Microsyst Nanoeng] Full Article

SKELETAL MUSCLE CELLS

Lnc-Mg Is a Long Non-Coding RNA that Promotes Myogenesis

The specific roles of long noncoding RNAs (lncRNAs) in myogenic differentiation of adult skeletal muscle stem cells and myogenesis are still largely unknown. Scientists identified a lncRNA that is specifically enriched in skeletal muscle (myogenesis-associated lncRNA, in short, lnc-mg). In mice, conditional knockout of lnc-mg in skeletal muscle results in muscle atrophy and the loss of muscular endurance during exercise. [Nat Commun] Full Article

R-spondin1 Controls Muscle Cell Fusion through Dual Regulation of Antagonistic Wnt Signaling Pathways

Researchers showed that deletion of Rspo1 results in global alteration of muscle regeneration kinetics following acute injury. They found that muscle progenitor cells lacking Rspo1 show delayed differentiation due to reduced activation of Wnt/β-catenin target genes. Muscle cells lacking Rspo1 have a fusion phenotype leading to larger myotubes containing supernumerary nuclei both in vitro and in vivo. [Cell Rep] Full Article | Graphical Abstract

Complement C3 of the Innate Immune System Secreted by Muscle Adipogenic Cells Promotes Myogenic Differentiation

Investigators showed that muscle-resident pre-adipocytes promote myogenic differentiation through the secretion of factors. Using proteomic and transcriptomic analyses, they identified that proliferative adipogenic lineage cells produce and secrete a key factor of the innate immune system, the complement C3. Cell culture experiments revealed that C3 promotes the differentiation of myogenic progenitors following internalization of the immune molecule. [Sci Rep] Full Article

Ten-Eleven Translocation-2 (Tet2) Is Involved in Myogenic Differentiation of Skeletal Myoblast Cells In Vitro

Scientists demonstrated that Tet2, a ten-eleven translocation (Tet) methylcytosine dioxygenase, exerts a role during skeletal myoblast differentiation. By using an immunostaining method, they found that the levels of 5-hydroxymethylcytosine were much higher in differentiated myotubes than in undifferentiated C2C12 myoblasts. [Sci Rep] Full Article

SMOOTH MUSCLE CELLS

Atractylenolide I Restores HO-1 Expression and Inhibits Ox-LDL-Induced VSMCs Proliferation, Migration and Inflammatory Responses In Vitro

Investigators aimed to elucidate the effect of atractylenolide I on smooth muscle cell inflammation, proliferation and migration induced by oxidized modified low density lipoprotein (Ox-LDL). They found that atractylenolide I inhibited Ox-LDL-induced vascular smooth muscle cells (VSMCs) proliferation and migration in a dose-dependent manner, and decreased the production of inflammatory cytokines and the expression of monocyte chemoattractant protein-1 in VSMCs. [Exp Cell Res] Abstract

Smooth Muscle Cell-Specific Deletion of Col15a1 Unexpectedly Leads to Impaired Development of Advanced Atherosclerotic Lesions

The authors provided the first direct evidence that a smooth muscle cells-derived collagen, collagen type XV (COL15A1), is critical during lesion pathogenesis but contrary to expectations, its loss resulted in marked attenuation rather than exacerbation of lesion pathogenesis. [Am J Physiol Heart Circ Physiol] Abstract

Sarcoplasmic Reticulum-Mitochondria Communication in Cardiovascular Pathophysiology

The authors summarize the evidence related to the role of sarco/endoplasmic reticulum–mitochondria communication in cardiac and vascular muscle physiology, with a focus on how perturbations contribute to the pathogenesis of cardiovascular disorders. [Nat Rev Cardiol] Abstract

A Growing Role for the Hippo Signaling Pathway in the Heart

Researchers review the function of canonical and non-canonical Hippo signaling in cardiomyocytes, with a particular focus on proliferation and survival, and how this impacts the stressed adult heart. [J Mol Med (Berl)] Abstract

Visit our reviews page to see a complete list of reviews in the muscle cell research field.

Government of Canada Provides Almost $5 Million for U of T Cutting-Edge Research

Nineteen scholars at the University of Toronto have been awarded almost $5 million to support research in everything from using stem cells to fix injured hearts to creating an advanced laboratory to develop large astronomical telescopes. [University of Toronto] Press Release

MDA Awards More than $7 Million in New Research Grants

The Muscular Dystrophy Association announced the award of 29 new research and development grants totaling more than $7 million and targeted to impact the state of the science and accelerate the development of treatments for muscular dystrophy, ALS and related life-threatening diseases. [Muscular Dystrophy Association (PR Newswire Association LLC.)] Press Release

Canada’s New Genetic Privacy Law Is Causing Huge Headaches for Justin Trudeau

A vote in Canada’s Parliament to approve a genetic privacy bill is creating a self-inflicted political headache for Prime Minister Justin Trudeau’s Liberal government—and could result in a relatively rare and unusual court case. [ScienceInsider] Editorial

Physician with Drug-Industry Ties Is Trump’s FDA Pick

President Donald Trump has nominated Scott Gottlieb — a conservative pundit, physician and venture capitalist — to head the US Food and Drug Administration (FDA). [Nature News] Editorial

NEW Advances in Sarcomas: From Basic Science to Clinical Translation
May 16-19, 2017
Philadelphia, United States

Visit our events page to see a complete list of events in the community.

NEW Postdoctoral Scholar – Stem Cell Biology and Endocrinology (Stanford University)

Postdoctoral Fellow – Cellular Mechanobiology (University of Buffalo)

Postdoctoral Fellowship – Heart Regeneration (Children’s Hospital Los Angeles – University of Southern California)

Postdoctoral Research Scientist – Cardiovascular Research (Rutgers New Jersey Medical School)

Postdoctoral Fellow – Stem Cell Biology and Pharmacogenomics (Northwestern University Feinberg School of Medicine)

Postdoctoral Candidate – Cardiovascular Biology and Disease (University at Buffalo)

Postdoctoral Fellow – Cell and Gene Therapy for Cardiac Arrhythmias (Duke University)

Postdoctoral Fellow – Genome Editing for Cardiac Muscle Regeneration (Duke University)

Postdoctoral Position – In Vitro Modeling of Human Skeletal Muscle Disease (Duke University)

Postdoctoral Fellow – hiPSC-Based Heart Repair (Duke University)

Postdoctoral Researcher – Muscle Biology and Muscle Disease (University of Pennsylvania)

Postdoctoral Fellow – Epigenomics of Cardiac Development and iPSC/ESC Differentiation (Stanford Cardiovascular Institute)

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