Spatially Resolved Metabolomics Method for Mapping the Global Molecular Landscape of Whole-Body Zebrafish (Danio rerio) Using Ambient Mass Spectrometry Imaging

Zebrafish (Danio rerio) representan effective model biological material for human disease research,even for personalized precision medicine. Thus, it is necessary tofully characterize their molecular information in order to obtaina global metabolic profile. Here, a spatially resolved metabolomicsmethod for whole-body zebrafish analysis was established based onan air-flow-assisted desorption electrospray ionization-mass spectrometryimaging (AFADESI-MSI) system. Using the optimized experimental conditions,the method provided high-quality visual distribution information for>1000 functional metabolites, thereby organ-specific metabolitescharacterizingnine regions were obtained comprehensively, including the eyes, brain,gill, heart, liver, kidney, intestine, muscle, and spinal cord. Then,combined with metabolic pathway analysis, a global metabolic networkwith in situ information on zebrafish was mappedfor the first time. We also tried to use the recently published MSIdatabase to annotate the metabolites in this study; however, the annotationrate was only 33.7 and 10.4% in positive and negative modes, respectively.This further demonstrated the necessity of establishing a suitableAFADESI-MSI method for zebrafish samples. These results offer comprehensiveand in-depth molecular information about zebrafish at the metaboliclevel, which facilitates the use of zebrafish models to understandmetabolic reprogramming in human diseases and the development of zebrafishdisease models.

Automated summary

By establishing an AFADESI-MSI system, the molecular information of zebrafish was fully characterized, providing high-quality visual distribution information for over 1000 functional metabolites and mapping a global metabolic network. This comprehensive and in-depth molecular information facilitates the use of zebrafish models in understanding human diseases and developing zebrafish disease models.