AUTHOR=Ren Huiying , Pu Zhaoli , Sun Tianyi , Chen Tangting , Liu Leiying , Liu Zhu , O’Shea Christopher , Pavlovic Davor , Tan Xiaoqiu , Lei Ming 

TITLE=High-Resolution 3D Heart Models of Cardiomyocyte Subpopulations in Cleared Murine Heart

JOURNAL=Frontiers in Physiology

VOLUME=Volume 13 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2022.779514

DOI=10.3389/fphys.2022.779514

ISSN=1664-042X

ABSTRACT=


Biological tissues are naturally three-dimensional (3-D) opaque structures, which poses a major challenge for deep imaging of spatial distribution and localization of specific cell types in organs in biomedical research.  Here we present a 3-D heart imaging reconstruction approach by combining an improved heart tissue-clearing technique with high-resolution light-sheet fluorescence microscopy (LSFM). We have conducted three-dimensional and multi-scale volumetric imaging of ultra-thin planes of murine hearts for up to 2,000 images per heart in x-, y- and z three directions.  High-resolution 3-D volume heart models were constructed in real-time by the Zeiss Zen programme. By using such approach, we investigated detailed three-dimensional spatial distributions of two specific cardiomyocyte populations including HCN4 expressing pacemaker cells and Pnmt+ cell-derived cardiomyocytes by using reporter mouse lines Hcn4DreER/tdTomato and PnmtCre/ChR2-tdTomato. HCN4 is distributed throughout right atrial nodal regions (i.e. sinoatrial and atrioventricular nodes) and the superior-inferior vena cava axis, while Pnmt+ cell derived cardiomyocytes show distinct ventral, left heart and dorsal side distribution pattern.  Our further electrophysiological analysis indicates that Pnmt+cell-derived cardiomyocytes rich left ventricular (LV) base has higher susceptible to ventricular arrhythmia under adrenergic stress than LV apex, right ventricle regions.    Thus our 3-D heart imaging reconstruction approach provides a new solution for studying geometrical, topological and physiological characteristics of specific cell types in organs.