RESEARCH ARTICLE
Body composition and hormonal effects following
exposure to mycotoxin deoxynivalenol in the high-fat
diet-induced obese mouse
Kazuo Kobayashi-Hattori1,2, Chidozie J. Amuzie1,3,4, Brenna M. Flannery1,4
and James J. Pestka1,4,5
1 Department of Food Science and Human Nutrition, Michigan State University, East Lansing, MI, USA
2 Department of Nutritional Science, Faculty of Applied Bioscience, Tokyo University of Agriculture, Tokyo, Japan
3 Pathobiology and Diagnostic Investigation, Michigan State University, East Lansing, MI, USA
4 Center for Integrative Toxicology, Michigan State University, East Lansing, MI, USA
5 Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI, USA
Received: December 17, 2010
Revised: February 6, 2011
Accepted: February 24, 2011
Scope: To characterize the effects of ingesting the common foodborne mycotoxin deox-
ynivalenol (DON) on body weight and composition in the high-fat (HF) diet-induced obese
mice, a model of human obesity.
Methods and results: Female B6C3F1 mice were initially fed HF diets containing 45% kcal
(HF45) or 60% kcal (HF60) as fat for 94 days to induce obesity. Half of each group was either
continued on unamended HF diets or fed HF diets containing 10 mg/kg DON (DON-HF45 or
DON-HF60) for another 54 days. Additional control mice were fed a low-fat (LF) diet containing
10% kcal as fat for the entire 148-day period. DON induced rapid decreases in body weights and
fat mass, which stabilized to those of the LF control within 11 days. These effects corresponded
closely to a robust transient decrease in food consumption. While lean body mass did not
decline in DON-fed groups, further increases were suppressed. DON exposure reduced plasma
insulin, leptin, insulin-like growth factor 1, and insulin-like growth factor acid labile subunit as
well as increased hypothalamic mRNA level of the orexigenic agouti-related protein.
Conclusion: DON-mediated effects on body weight, fat mass, food intake, and hormonal levels
in obese mice were consistent with a state of chronic energy restriction.
Keywords:
Deoxynivalenol / Diet-induced obesity / Food intake / Hormone / Trichothecene
1 Introduction
Deoxynivalenol (DON), a trichothecene mycotoxin produced
by the phytopathogenic, fungus Fusarium, commonly
contaminates grains such as wheat, barley, and corn
worldwide and is relatively recalcitrant to food processing
[1]. DON intake by humans has been estimated to be 2.4,
1.6, 1.4, 1.2, and 0.8 mg/kg bw/day in the Middle East, Far
East, Europe, Latin America and Africa, respectively [2].
Because of its frequent occurrence in grain-based foods, it is
critical to understand how DON and related trichothecenes
impact humans. Exposure of monogastric species such as
pigs to low or moderate DON concentrations in feed causes
impaired weight gain, whereas high DON doses cause
malaise, diarrhea, and emesis [3].
Suppression of weight gain in mice has been used as the
metric for establishing the tolerable daily intake of this toxin
[2]; however, the underlying mechanisms remain poorly
understood. Many investigations have suggested that DON
impairs body weight increase and induces body weight
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Abbreviations: AgRP, agouti-related protein; CART, cocaine- and
amphetamine-regulated transcript; DON, deoxynivalenol;
5-HT, 5-hydroxytryptamine; HF, high fat; IGF-1, insulin-like
growth factor 1; IGFALS, IGF acid labile subunit; IGFBP,
IGF-binding protein; LF, low fat; NPY, neuropeptide Y; POMC,
pro-opiomelanocortin
Correspondence: Professor James J. Pestka, Department of
Food Science and Human Nutrition, 234A G.M. Trout Building,
Michigan State University, East Lansing, MI 48824, USA
E-mail: pestka@msu.edu
Fax: 11-517-353-8963
& 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim www.mnf-journal.com
Mol. Nutr. Food Res. 2011, 55, 1–9 1DOI 10.1002/mnfr.201000640

loss by suppressing food intake [4, 5]. For example, the
consumption of DON at 0.25–1.0 mg/kg bw and at 1.0 mg/
kg bw by female and male rats, respectively, for 9 wk caused
both decreased feed consumption and body weight gain [4].
Similarly, DON consumption (0.35 and 1.3 mg/kg bw)
caused reductions in food consumption and body weight
after 1 wk in mice [5].
DON’s anorexic effects are possibly mediated via the
brain. The hypothalamus controls food intake by balancing
the levels of anorexic and orexigenic peptides such as pro-
opiomelanocortin (POMC), a-melanocyte stimulating
hormone (a-MSH), neuropeptide Y (NPY), and agouti-rela-
ted peptide (AgRP) [6]. Notably, there is a strong inverse
relationship between food consumption and brain levels of
serotonin (5-hydroxytryptamine, 5-HT), an important
upstream regulator of aforementioned peptides [7]. Since
DON is detectable in brain following oral administration [8],
the toxin has the potential to interfere with normal appetite
regulation. In support of this contention, exposure to DON
at 2.5 mg/kg bw significantly increases serotonin levels in
cerebellum and hypothalamus in rats at 24 h after admin-
istration [9, 10]. Relatedly, acute DON administration
(0.25 mg/kg bw) enhances the level of serotonin in hypo-
thalamus of swine [11]. Therefore, altered serotonin in the
brain could mediate DON-induced feed refusal and subse-
quent body weight effects.
Two other hormones that may impact DON-induced
weight changes are insulin-like growth factor 1 (IGF-1) and
IGF acid labile subunit (IGFALS). Prior studies in our
laboratory demonstrated that DON exposure reduced
expression of IGF-1 and IGFALS mRNA and protein [12,
13]. Notably, the latter protein prolongs half-life of circulat-
ing IGF-1 by forming ternary complex with IGF-1 and IGF-
binding protein (IGFBP)-3/IGFBP-5 [14].
Given the current worldwide epidemic of human obesity,
it is essential to understand how foodborne toxins such as
DON might affect obese individuals. This is further
important because DON and its derivatives have
been proposed as potential pharmacotherapeutics for
treating human obesity [15]. We have recently reported
that DON suppresses body weight increase in mice
fed high fat (HF) diets as well as causes reduction
in body weights in HF-induced obese mice [16]. These
effects were linked to decreased terminal periuterine fat,
suggesting that there was a concurrent reduction in
adiposity. Several critical questions remain regarding the
effects of DON on body weight loss in obese adult animals,
particularly as related to mechanisms and whether these
effects are linked to loss of lean body mass as occurs in
cachexia.
The purpose of this study was to relate DON-induced
body weight loss in HF-induced obese mice to food intake,
fat mass, lean mass, and obesity-related hormones.
DON-mediated body weight effects were found to corre-
spond to transiently reduced food intake and to decreased
body fat mass but not to reduction of basal lean weight.
Further consistent with a state of chronic energy restriction,
DON exposure decreased plasma concentrations of insulin,
leptin, IGF-1, and IGFALS in obese mice as well as
increased the hypothalamic mRNA level of the orexigenic
peptide AgRP.
2 Materials and methods
2.1 Experimental design
Mice were maintained according to National Institute of
Health guidelines as overseen by the All University
Committee on Animal Use and Care at Michigan State
University (Approval No. 01/08-007-00). Pathogen-free
female adult B6C3F1 mice (11-wk old, Charles River
Laboratories, Portage, MI) were housed in polycarbonate
cages under controlled temperature (21–241C), humidity
(40–55%), and lighting (12 h light:dark cycle). Boxes were
covered with filter bonnets and mice were allowed free
access to food and water.
Diets employed are summarized in Table 1. Mice (n5 40)
were fed low fat (LF) containing 10% kcal in fast diet (LF,
D12450B) (Research Diet, New Brunswick, NJ) during a 1-wk
acclimatization period. The remaining mice were fed HF
diets containing either 45 kcal% as fat (HF45, Research Diet
D12451) (n5 16) or 60 kcal% as fat (HF60, Research Diet
D12492) (n5 16) to induce obesity. Following induction of
the obese state at 94 days, each of these HF groups was
subdivided into two groups (n5 8) and fed either unamended
HF diets (HF45 or HF60) or HF diets amended with 10 mg/
kg DON (DON-HF45 or DON-HF60) until 148 days. This
dose was selected based on its capacity to evoke body weight
loss in our previous study [16]. In addition to these groups,
another control group of mice was maintained on LF (n5 8)
for experiment duration (148 days).
Food intake, body weight, fat mass, and lean mass of the
mice were monitored and blood was collected from the
saphenous vein at intervals throughout the experiment. At
the end of the feeding period, blood was collected from
anesthetized mice that had been fasted for 4 h to achieve a
nonfed state and the hypothalamus was removed following
euthanasia. Plasma was frozen at 801C for glucose and
hormone analysis. The hypothalamus was stored in
RNAlaters (Ambion, Austin, TX) at 201C prior to RNA
extraction.
2.2 Body composition
Body fat mass and lean mass were quantified in live mice by
magnetic resonance imaging using an EchoMRI-100TM
(Echo Medical Systems, LLC, Houston, TX). The body fat
percentage was calculated using the following formula: body
fat percentage (%)5 body fat mass (g)/body weight
(g) 100.
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2 K. Kobayashi-Hattori et al. Mol. Nutr. Food Res. 2011, 55, 1–9
& 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim www.mnf-journal.com