Degree Type

Dissertation

Date of Award

2008

Degree Name

Doctor of Philosophy

Department

Food Science and Human Nutrition

First Advisor

Suzanne Hendrich

Abstract

Deoxynivalenol (DON), produced by Fusarium graminearum and Fusarium culmorum , is commonly found in wheat, corn, oats and barley. We hypothesize DON exposure could change leukocyte subset number and their migration potential in peripheral blood with interaction of age and sex, which could be sensitive biomarkers to predict DON exposure for human epidemiological screening.

The first mouse study was done in 6-7 week old BALB/c mice. Peripheral blood (PB) and splenic leukocytes were stained and detected by flow cytometry. The results showed the percentage of B cells (CD19+) in PB was reduced in both sexes at 1.0 and 2.0 ppm at 14 d, with no reduction of B cells after 28 d. Monocytes (CD11b+) in PB and macrophage cells (CD11b+) in spleen were decreased in female BALB/c mice at 1.0 and 2.0 ppm after 28 d, which suggested sex hormones interacted with DON immunotoxicity. No toxicity was observed at doses 0.5 ppm or less.

The second mouse study was done in 2-3 month old and 16 month old BALB/c mice. Granulocytes in both ages and sexes were increased at 1.0 and 2.0 ppm DON at 14 d, but normalized after 28 d. Percentage of T helper cells in PB was decreased in young female mice fed 2.0 ppm DON after 14 d, not after 28 d. Percentage of CXCR5+ B cells was decreased in old female mice fed 2.0 ppm DON after 14 d, but not after 28 d. CD29+CD11a+ neutrophils were increased at 1.0 and 2.0 ppm DON in old male mice after 14 d, but no difference was observed after 28 d. CCR9+ T cytotoxic cells were increased in old male mice fed 2.0 ppm DON after 28 d. Taken together, these results suggested DON inhibited T helper cells in young female mice and interrupted B cell, neutrophil and T cytotoxic cell migration potentials in old mice. Most DON toxicity was transient, and interacted with age and sex.

In conclusion, the surface markers of leukocytes in PB were changed in BALB/c mice fed 1.0 ppm and 2.0 ppm DON. Age and sex interacted with DON exposure. Most of the effects of DON were temporary, which suggested BALB/c mice adapted to DON exposure.

DOI

https://doi.org/10.31274/etd-180810-2573

Copyright Owner

Xianai Wu

Language

en

Date Available

2012-04-29

File Format

application/pdf

File Size

164 pages

Included in

Nutrition Commons

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