GNPS - Relationship between thyroid hormones and associated metabolites and gene expression bioindicators in the serum of Rana [Lithobates] catesbeiana tadpoles and frogs during metamorphosis

Anuran metamorphosis is characterized by profound morphological changes including remodeling of tissues and organs. Here we investigate serum of Rana [Lithobates] catesbeiana (n=5-10) across seven distinct postembryonic stages beginning with premetamorphic tadpole (Gosner stage 31-33) and continuing through metamorphosis to a juvenile frog (Gosner stage 46). Using a sensitive nanoLC-Orbitrap system an untargeted analysis workflow was applied. Among 6,062 detected endogenous metabolites, 421 showed significant metamorphosis-dependent concentration dynamics. Among these potential bioindicators were several prostaglandins and other eicosanoids, some steroid hormones including testosterone, and several carnitines. These data provide a necessary context for interpreting developmental processes and potential molecular crosstalk mechanisms. Furthermore, this provides a solid foundation from which alternative bioindicators of metamorphosis may be chosen as feasible endpoints in future risk assessment of chemicals and their potency for causing developmental toxicity.