Summary of project PR001828

This data is available at the NIH Common Fund's National Metabolomics Data Repository (NMDR) website, the Metabolomics Workbench, https://www.metabolomicsworkbench.org, where it has been assigned Project ID PR001828. The data can be accessed directly via it's Project DOI: 10.21228/M8F14S This work is supported by NIH grant, U2C- DK119886.

See: https://www.metabolomicsworkbench.org/about/howtocite.php

Project ID: PR001828
Project DOI:doi: 10.21228/M8F14S
Project Title:Role of PI3K in Atrial Myopathy: Insights from Transgenic Mouse Models and Identification of a Dysregulated PI3K Lipid Profile in Individuals with Atrial Fibrillation
Project Summary:In a serendipitous discovery, atrial enlargement, fibrosis and thrombi was identified in a subset of transgenic mice with reduced phosphoinositide 3-kinase (PI3K, class IA) in cardiac myocytes. Understanding mechanisms underlying atrial myopathy has important implications for understanding and preventing atrial fibrillation (AF). Prior work had shown that PI3K is an essential regulator of exercise-induced ventricular enlargement and protection, but the role in the atria was unknown. Further, while targeting IGF1-PI3K-Akt signaling has been considered a potential therapeutic strategy for the failing heart, growing evidence suggests fine-tuning IGF1-PI3K signaling would be necessary. Here, we undertook comprehensive physiological and molecular analyses in cardiac-specific transgenic mice with increased or decreased PI3K to assess the dose response impact of directly regulating PI3K. Elevated PI3K was associated with a dose-dependent increase in heart size, and preserved/enhanced function. In contrast, reduced PI3K led to cardiac dysfunction, fibrosis, arrhythmia, and increased susceptibility to atrial enlargement and thrombi. This phenotype was associated with dysregulation of a lipid species (GM3) that regulates the IGF1-PI3K pathway, cardiac stress and contractility genes. Proteomic profiling identified distinct signatures across atria with varying degrees of atrial dysfunction, enlargement, and presence of atrial thrombi. To assess the potential relevance in humans we assessed circulating PI3K-related lipids in plasma from athletes with/without AF. Dysregulation of GM3 and PI3K-related lipids were identified in athletes with AF. Collectively, this work advances our understanding of mechanisms underpinning atrial pathophysiology, offers new insights for therapeutic approaches targeting atrial myopathy and AF, and has identified potential new lipid markers for identifying individuals at risk of AF.
Institute:Baker Heart and Diabetes Institute
Laboratory:Metabolomics
Last Name:Tham
First Name:Yow Keat
Address:75 Commercial Rd, Melbourne, Victoria, 3004, Australia
Email:yowkeat.tham@baker.edu.au
Phone:0430502623

Summary of all studies in project PR001828

Study IDStudy TitleSpeciesInstituteAnalysis
(* : Contains Untargted data)
Release
Date
VersionSamplesDownload
(* : Contains raw data)
ST002938 Role of PI3K in Atrial Myopathy: Insights from Transgenic Mouse Models and Identification of a Dysregulated PI3K Lipid Profile in Individuals with Atrial Fibrillation - part 1 of 2, human plasma Homo sapiens Baker Heart and Diabetes Institute MS 2025-01-12 1 78 Uploaded data (359.9M)*
ST002939 Role of PI3K in Atrial Myopathy: Insights from Transgenic Mouse Models and Identification of a Dysregulated PI3K Lipid Profile in Individuals with Atrial Fibrillation - Part 2 of 2, Mus musculus Mus musculus Baker Heart and Diabetes Institute MS 2025-01-12 1 209 Uploaded data (932.7M)*
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