An overview of renal metabolomics

Abstract

The high-throughput, high-resolution phenotyping enabled by metabolomics has been increasingly applied to a variety of questions in nephrology research. This article provides an overview of current metabolomics methodologies and nomenclature, citing specific considerations in sample preparation, metabolite measurement, and data analysis that investigators should understand when examining the literature or designing a study. Further, we review several notable findings that have emerged in the literature that both highlight some of the limitations of current profiling approaches, as well as outline specific strengths unique to metabolomics. More specifically, we review data on 1.) tryptophan metabolites and CKD onset, illustrating the interpretation of metabolite data in the context of established biochemical pathways; 2.) trimethylamine-N-oxide and cardiovascular disease in CKD, illustrating the integration of exogenous and endogenous inputs to the blood metabolome; and 3.) renal mitochondrial function in diabetic kidney disease and AKI, illustrating the potential for rapid translation of metabolite data for diagnostic or therapeutic aims. Finally, we review future directions, including the need to better characterize inter-person and intra-person variation in the metabolome, pool existing data sets to identify the most robust signals, and capitalize on the discovery potential of emerging non-targeted methods.

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