Access Type

Open Access Dissertation

Date of Award

January 2018

Degree Type

Dissertation

Degree Name

Ph.D.

Department

Biochemistry and Molecular Biology

First Advisor

William Brusilow

Abstract

ABSTRACT

METHIONINE SULFOXIMINE: A NOVEL ANTI-INFLAMMATORY AGENT

by

TYLER J. PETERS

October 2018

Advisor: William Brusilow

Major: Biochemistry and Molecular Biology

Degree: Doctor of Philosophy

The glutamine synthetase inhibitor methionine sulfoximine (MSO), shown previously to prevent death caused by an inflammatory liver response in mice, was tested on in vitro production of cytokines by mouse peritoneal macrophages triggered with lipopolysaccharide (LPS). MSO significantly reduced the production of Interleukin 6 (IL-6) and Tumor Necrosis Factor Alpha (TNFα) at 4 and 6 hours after LPS-treatment. This reduction did not result from decreased transcription of IL-6 and TNFα genes, and therefore appeared to result from post-transcriptional inhibition of synthesis of these cytokines. MSO treatment did not inhibit total protein synthesis and did not reduce the production of a third LPS-triggered cytokine CXCL1, so the effect was not a toxic or global downregulation of the LPS response. The anti-inflammatory effects of a glutamine synthetase inhibitor were seen even though the medium contained abundant (2 mM) glutamine, suggesting that the target for this activity was not glutamine synthetase. In agreement with this hypothesis, the L,R isomer of MSO, which does not inhibit glutamine synthetase and was previously thought to be inert, both significantly reduced IL-6 secretion in isolated macrophages and increased survival in a mouse model for inflammatory liver failure. Our findings provide evidence for a novel target of MSO. Future attempts to identify the additional target would therefore also provide a target for therapies to treat diseases involving damaging cytokine responses.

Included in

Biochemistry Commons

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