IADR Abstract Archives

Metabolomics of Extracellular Vesicles Reveals Distinct Molecular Signatures of Clastic Cells

Objectives: Extracellular vesicles (EVs) are nanometer-sized vesicles released by cells that are emerging as sources of biomarkers. With the development of metabolomics, it is now possible to study small molecules that are part of the EV cargo. In this study, we compared the composition of different metabolites in EVs purified from clastic cells resorbing bone (osteoclasts), clastic cells resorbing dentin (odontoclasts) and non-resorbing clasts with the main goal of finding molecules that can distinguish between these biological processes.
Methods: Hematopoietic cells from mouse marrow were cultured on plastic (control), bone, and dentin in the presence of RANKL and M-CSF for 4 days. EVs were isolated from the media by ultracentrifugation and analyzed by untargeted metabolomics on a Thermo Q-Exactive Oribtrap mass spectrometer with Dionex UHPLC and autosampler. Pooled samples from triplicate cultures, along with the individual samples, were analyzed in positive and negative heated electrospray ionization with a mass resolution of 35,000 at m/z 200 as separate injections. Univariate analysis by ANOVA was carried out on all data sets. Multivariate analysis was performed using principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA).
Results: 1268 metabolites were detected from the positive mode and 849 metabolites detected in the negative mode. Comparison of the metabolome identified 100 known and 878 unknown metabolites that were significantly different (p<.05) between bone, dentin and plastic. There were 39 (positive) and 40 (negative) metabolites from PLS-DA that were significant with a variable importance in projection (VIP) score of 2 or greater. Some of the top known metabolites differentiating exosomes secreted by osteoclasts, odontoclasts and non-resorbing clasts include cytidine, thymine, glycerophosphocol, cytrulline, succinate, deoxycytidine, oridine, deoxyuridine and alpha-hydroxyisobuytryic acid.
Conclusions: Resorption of different mineralized matrices results in the release of EVs with distinct metabolite profiles. This finding should be further explored for biomarker discovery.
IADR/AADR/CADR General Session
2020 IADR/AADR/CADR General Session (Washington, D.C., USA)
Washington, D.C., USA
2020
0070
Craniofacial Biology Research
  • Rody, Wellington  ( Stony Brook University , Stony Brook , New York , United States )
  • Garrett, Timothy  ( University of Florida , Gainesville , Florida , United States )
  • Holliday, Lexie  ( University of Florida , Gainesville , Florida , United States )
  • NIH-NIDCR R03 DE027504-02
    NONE
    Oral Session
    Bone Biology I