A high-definition spatially resolved metabolomics method to illuminate the metabolic specificity and interconnection across mouse brain

The brain's functions are governed by molecular metabolic networks. However, due to the sophisticated spatial organization and diverse activities of the brain, characterizing both the minute and large-scale metabolic activity across the entire brain and its numerous micro-regions remains incredibly challenging. Here, we offer a high-definition spatially resolved metabolomics technique to better understand the metabolic specialization and interconnection throughout the mouse brain using improved ambient mass spectrometry imaging. This method allows for the simultaneous mapping of thousands of metabolites at a 30 µm spatial resolution across the mouse brain, ranging from structural lipids to functional neurotransmitters. This approach effectively reveals the distribution patterns of delicate microregions and their distinctive metabolic characteristics. Using an integrated database, we annotated 259 metabolites, demonstrating that the metabolome and metabolic pathways are unique to each brain microregion. The distribution of metabolites, closely linked to functionally connected brain regions and their interactions, offers profound insights into the complexity of chemical processes and their roles in brain function. An initial dataset for future metabolomics research might be obtained from the high-definition mouse brain's spatial metabolome atlas. A tiny desorption probe featuring an off-axis solvent capillary with an inner diameter of 20 µm has been developed for AFADESI-MSI. This innovative probe not only enhances the spatial resolution of MSI to a high definition level but also enables spatially resolved metabolomics analysis without compromising sensitivity. Consequently, it brings to light the metabolic specificity and interconnections within the mouse brain.