Cardiac pathologies in mouse loss of imprinting models are due to misexpression of H19 long noncoding RNA
Abstract
Maternal loss of imprinting (LOI) at the H19/IGF2 locus results in biallelic IGF2 and reduced H19 expression and is associated with Beckwith-Wiedemann syndrome (BWS). We use mouse models for LOI to understand the relative importance of Igf2 and H19 mis-expression in BWS phenotypes. Here we focus on cardiovascular phenotypes and show that neonatal cardiomegaly is exclusively dependent on increased Igf2. Circulating IGF2 binds cardiomyocyte receptors to hyperactivate mTOR signaling, resulting in cellular hyperplasia and hypertrophy. These Igf2-dependent phenotypes are transient: cardiac size returns to normal once Igf2 expression is suppressed postnatally. However, reduced H19 expression is sufficient to cause progressive heart pathologies including fibrosis and reduced ventricular function. In the heart, H19 expression is primarily in endothelial cells (ECs) and regulates EC differentiation both, in vivo and in vitro. Finally, we establish novel mouse models to show that cardiac phenotypes depend on H19 lncRNA interactions with Mirlet7 microRNAs.
Data availability
Sequencing data are deposited in the NCBI Gene Expression Omnibus (GEO) under series accession number GSE111418.
Article and author information
Author details
Funding
Eunice Kennedy Shriver National Institute of Child Health and Human Development Division of Intramural Research (ZIAHD001804)
- Karl Pfeifer
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Benjamin L Prosser, University of Pennsylvania Perelman School of Medicine, United States
Ethics
Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All animals were handled according to approved institutional animal care and use committee (IACUC) protocols (050 and 063) of the Eunice Kennedy Shriver National Institute of Child Health and Human Development. Surgery was performed under Avertin anesthesia and every effort was made to minimize suffering.
Version history
- Received: February 5, 2021
- Preprint posted: February 23, 2021 (view preprint)
- Accepted: August 4, 2021
- Accepted Manuscript published: August 17, 2021 (version 1)
- Version of Record published: September 8, 2021 (version 2)
Copyright
This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.
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Human fetal development has been associated with brain health at later stages. It is unknown whether growth in utero, as indexed by birth weight (BW), relates consistently to lifespan brain characteristics and changes, and to what extent these influences are of a genetic or environmental nature. Here we show remarkably stable and lifelong positive associations between BW and cortical surface area and volume across and within developmental, aging and lifespan longitudinal samples (N = 5794, 4–82 y of age, w/386 monozygotic twins, followed for up to 8.3 y w/12,088 brain MRIs). In contrast, no consistent effect of BW on brain changes was observed. Partly environmental effects were indicated by analysis of twin BW discordance. In conclusion, the influence of prenatal growth on cortical topography is stable and reliable through the lifespan. This early-life factor appears to influence the brain by association of brain reserve, rather than brain maintenance. Thus, fetal influences appear omnipresent in the spacetime of the human brain throughout the human lifespan. Optimizing fetal growth may increase brain reserve for life, also in aging.
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