Metabolomic analysis of Shiga toxin 2a-induced injury in conditionally immortalized glomerular endothelial cells
Shiga toxin 2a (Stx2a) induces hemolytic uremic syndrome (STEC HUS) by targeting glomerular endothelial cells (GEC).
We investigated in a metabolomic analysis the response of a conditionally immortalized, stable glomerular endothelial cell line (ciGEnC) to Stx2a stimulation as a cell culture model for STEC HUS.
CiGEnC were treated with tumor necrosis factor-(TNF)α, Stx2a or sequentially with TNFα and Stx2a. We performed a metabolomic high-throughput screening by lipid- or gas chromatography and subsequent mass spectrometry. Metabolite fold changes in stimulated ciGEnC compared to untreated cells were calculated.
320 metabolites were identified and investigated. In response to TNFα + Stx2a, there was a predominant increase in intracellular free fatty acids and amino acids. Furthermore, lipid- and protein derived pro-inflammatory mediators, oxidative stress and an augmented intracellular energy turnover were increased in ciGEnC. Levels of most biochemicals related to carbohydrate metabolism remained unchanged.
Stimulation of ciGEnC with TNFα + Stx2a is associated with profound metabolic changes indicative of increased inflammation, oxidative stress and energy turnover.
KeywordsHemolytic uremic syndrome Shiga toxin Conditionally immortalized glomerular endothelial cells Metabolomics
We thank Prof. Peter Nawroth for kindly providing the laboratory facilities and Dr. Thomas Fleming for his valuable input and methodical assistance.
CP designed and performed research, analyzed and interpreted the data and wrote the first draft of the paper; KLP, CB and APO performed research, analyzed and interpreted the data; KLP, SCS, PWM, MB, HK and BT designed research, analyzed and interpreted the data, NR directed, designed, analyzed and interpreted the data and wrote the paper.
This work was supported by a Physician Scientist fellowship grant from the Medical Faculty of the University of Heidelberg to C.P., C.B. and N.R.
Compliance with ethical standards
Conflict of interest
KL.P. is an employee of Metabolon, Inc. and, as such, has affiliations with or financial involvement with Metabolon, Inc. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed. Besides that, there are no other financial or non-financial conflicts of interest.
Research involving human and/or animal participants
This article does not contain any studies with human and/or animal participants performed by any of the authors.
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