Fig. 1

The protective effect of QXY on the ISO-induced cardiac hypertrophy, dysfunction and injury in zebrafish. (A) Experimental flow and the demonstration of cardiac imaging and calculation of ventricular volume in transgenic zebrafish Tg (cmlc2: GFP) embryos. (B) The survival curve of 24 h post-fertilization (hpf) zebrafish embryos treated with various concentrations (100, 300, 600 and 1000 µg/ml) of QXY extract for 5 days. (C) The pictures demonstrated the end-diastolic and systolic images of ventricle in various treatment groups. (D) Twenty-four hpf zebrafish embryos were treated with ISO (1 mM), with or without various concentrations (100, 200 and 600 µg/ml) of QXY extract, for 48 h, then the cardiac morphology was observed by an inverted fluorescence microscope as well as the calculation of heart rate, cardiac output, stroke volume, ejection fraction (EF), fractional shortening (FS), ventricular end-diastolic area (SVED), ventricular end-systolic area (SVES), SVED - SVES (∆S), ventricular end-diastolic volume (VVED) and ventricular end-systolic volume (VVES). Co-treatment of the beta-blocker propranolol (PRO, 10 µM) with ISO (1 mM) served as the positive control. (E) Twenty-four hpf zebrafish embryos were treated with ISO (1 mM), with or without QXY extract (600 µg/ml), for 48 h, then the mRNA expression levels of C-type natriuretic peptide (cnp), creatine kinase MB (ckmb) and cardiac troponin T 2 (ctnt2) were measured by real-time PCR, and the results were presented as folds of the control group. All the data were presented as mean ± SEM. #p < 0.05 and ###p < 0.001 vs control (Ctrl) group; *p < 0.05, **p < 0.01 and ***p < 0.001 vs ISO-treated group.