Metabolites and Lipids Associated with Fetal Swine Anatomy via Desorption Electrospray Ionization – Mass Spectrometry Imaging

Abstract

Chemical imaging by mass spectrometry (MS) has been largely used to study diseases in animals and humans, especially cancer; however, this technology has been minimally explored to study the complex chemical changes associated with fetal development. In this work, we report the histologically-compatible chemical imaging of small molecules by desorption electrospray ionization (DESI) - MS of a complete swine fetus at 50 days of gestation. Tissue morphology was unperturbed by morphologically-friendly DESI-MS analysis while allowing detection of a wide range of small molecules. We observed organ-dependent localization of lipids, e.g . a large diversity of phosphatidylserine lipids in brain compared to other organs, as well as metabolites such as N-acetyl-aspartic acid in the developing nervous system and N-acetyl-L-glutamine in the heart. Some lipids abundant in the lungs, such as PC(32:0) and PS(40:6), were similar to surfactant composition reported previously. Sulfatides were highly concentrated in the fetus liver, while hexoses were barely detected at this organ but were abundant in lung and heart. The chemical information on small molecules recorded via DESI-MS imaging coupled with traditional anatomical evaluation is a powerful source of bioanalytical information which reveals the chemical changes associated with embryonic and fetal development that, when disturbed, causes congenital diseases such as spina bifida and cleft palate.

Dynamic mRNA Expression Analysis of the Secondary Palatal Morphogenesis in Miniature Pigs

“…In Meis2 -null mouse embryos, severely abnormal developing cartilage was observed in the palate, and 67% of mutants also presented malformed palates, though this was less severe [39]. At approximately E50, organogenesis of the swine heart can be observed [40], and we speculated that this stage was also an important stage for the heart development of miniature pigs, and some genes might influence both the heart and palate. During this stage, the palate shelves fuse, and bone formation proceeds.…”

Metabolites from Microbes Isolated from the Skin of the Panamanian Rocket Frog Colostethus panamansis (Anura: Dendrobatidae)

“…3D molecular cartography studies have been implemented to integrate and interpret molecular results in large studies (i.e., genomics and metabolomics) from human, host-parasites and plant-related samples [ 32 , 35 , 36 , 78 ]; however, such studies have not been conducted in amphibians. By generating a 3D molecular cartography model of an amphibian, i.e., the Panamanian rocket frog C. panamansis , it was possible to visualize and understand the body distribution of skin-associated molecules and their bacterial producers [ 32 , 35 , 79 ]. Although isolation of amphibian’s strains is common, understanding their body distribution and their role in the environment can be helpful in the selection of isolates for further novel secondary metabolite discovery.…”

Enhancement of Fear Extinction Memory and Resistance to Age-Related Cognitive Decline in Butyrylcholinesterase Knockout Mice and (R)-Bambuterol Treated Mice

“…The m/z of the substances collected from mass spectrometry imaging was queried through public databases https://hmdb.ca/ (accessed on 13 December 2020) and https: //www.lipidmaps.org/ (accessed on 14 December 2020). The substances were determined in conjunction with relevant literature reports [33]. Three animals were selected randomly in each group for the immunohistochemistry and mass spectrometry imaging, and 6-9 mice per group were analyzed in other experiments.…”