Format

Send to

Choose Destination
Front Immunol. 2018 Jun 5;9:1242. doi: 10.3389/fimmu.2018.01242. eCollection 2018.

Distinct Immunomodulatory Effects of Spermine Oxidase in Colitis Induced by Epithelial Injury or Infection.

Author information

1
Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, United States.
2
Center for Mucosal Inflammation and Cancer, Vanderbilt University Medical Center, Nashville, TN, United States.
3
Veterans Affairs Tennessee Valley Healthcare System, Nashville, TN, United States.
4
Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN, United States.
5
Department of Tumor Biology, Moffitt Cancer Center and Research Institute, Tampa, FL, United States.
6
Department of Cancer Biology, The Scripps Research Institute, Jupiter, FL, United States.
7
Johns Hopkins University, Sidney Kimmel Comprehensive Cancer Center, Baltimore, MD, United States.
8
Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN, United States.

Abstract

Polyamines have been implicated in numerous biological processes, including inflammation and carcinogenesis. Homeostatic regulation leads to interconversion of the polyamines putrescine and the downstream metabolites spermidine and spermine. The enzyme spermine oxidase (SMOX), which back-converts spermine to spermidine, contributes to regulation of polyamine levels, but can also have other effects. We have implicated SMOX in gastric inflammation and carcinogenesis due to infection by the pathogen Helicobacter pylori. In addition, we reported that SMOX can be upregulated in humans with inflammatory bowel disease. Herein, we utilized Smox-deficient mice to examine the role of SMOX in two murine colitis models, Citrobacter rodentium infection and dextran sulfate sodium (DSS)-induced epithelial injury. In C. rodentium-infected wild-type (WT) mice, there were marked increases in colon weight/length and histologic injury, with mucosal hyperplasia and inflammatory cell infiltration; these changes were ameliorated in Smox-/- mice. In contrast, with DSS, Smox-/- mice exhibited substantial mortality, and increased body weight loss, colon weight/length, and histologic damage. In C. rodentium-infected WT mice, there were increased colonic levels of the chemokines CCL2, CCL3, CCL4, CXCL1, CXCL2, and CXCL10, and the cytokines IL-6, TNF-α, CSF3, IFN-γ, and IL-17; each were downregulated in Smox-/- mice. In DSS colitis, increased levels of IL-6, CSF3, and IL-17 were further increased in Smox-/- mice. In both models, putrescine and spermidine were increased in WT mice; in Smox-/- mice, the main effect was decreased spermidine and spermidine/spermine ratio. With C. rodentium, polyamine levels correlated with histologic injury, while with DSS, spermidine was inversely correlated with injury. Our studies indicate that SMOX has immunomodulatory effects in experimental colitis via polyamine flux. Thus, SMOX contributes to the immunopathogenesis of C. rodentium infection, but is protective in DSS colitis, indicating the divergent effects of spermidine.

KEYWORDS:

colitis; infection; mucosal immune response; polyamines; spermidine; spermine oxidase

Supplemental Content

Full text links

Icon for Frontiers Media SA Icon for PubMed Central
Loading ...
Support Center