Oxidative stress affects cardiac looping in zebrafish embryos

HERRERA-ESTRADA, IDALIA; ARMESTO, RUBINA; BINOLFI, ANDRES; LOMBARDO, VERÓNICA A.

Córdoba

Congreso; LI Reunión Anual de la Sociedad Argentina de Biofísica; 2023

SAB

The morphogenesis of cardiac looping is essential and highly conserved in vertebrates. Anomalies in this process result in congenital heart defects in humans (1). The increase in reactive oxygen species levels during pregnancy influences embryonic development, specifically cardiac development (2,3). Zebrafish (Danio rerio) is a small vertebrate that offers numerous advantages for studying heart morphogenesis, including external embryogenesis, accessibility of the embryonic heart, its ability to survive several days with an abnormal heart, and its significant genetic homology with humans (4). To assess the effect of oxidative stress on cardiac looping we combine oxidant treatment with microscopy techniques using a zebrafish cardiac reporter line expressing GFP within myocardial tissue (5). Zebrafish embryos were treated with acute or gradual oxidative agents during cardiac looping. At the end of treatments, embryos were evaluated in vivo under fluorescent microscope and embryonic heart morphological parameters (shape and relative positioning of cardiac chambers) and cardio physiological evaluation (relative blood flow, red blood cell maturation, and heart rate) were carried out. Tridimensional images of representative embryonic hearts were perform under confocal microscope to quantify myocardial cell number and shape, and additional morphological parameters (6, 7). Our results show that oxidative stress conditions lead to abnormal cardiac looping in zebrafish embryos. Referencias: (1) Ramsdell, Dev Biol, 2005, 288:1-20. (2) Erickson et al., 2008 Cell, 133, 462–474 (3) Hobbs et al., 2005 The American Journal of Clinical Nutrition, 81, 147-153 (4) Bakkers, Cardiovascular Research, 2011, 10.1093/cvr/cvr098. (5) Huang et al., Dev Dyn., 2003, 228, 30-40. (6) Dietrich et al., Dev Cell, 2014, 30:367-377. (7) Lombardo et al., Development, 2019.