ABSTRACT
Physiological regulations of energy balance and body weight imply highly adaptive mechanisms which match caloric intake to caloric expenditure. In the central nervous system, the regulation of appetite relies on complex neurocircuitry which disturbance may alter energy balance and result in anorexia or obesity. Deoxynivalenol (DON), a trichothecene, is one of the most abundant mycotoxins found on contaminated cereals and its stability during processing and cooking explains its widespread presence in human food. DON has been implicated in acute and chronic illnesses in both humans and farm animals including weight loss. Here, we provide the first demonstration that DON reduced feeding behavior and modified satiation and satiety by interfering with central neuronal networks dedicated to food intake regulation. Moreover, our results strongly suggest that during intoxication, DON reaches the brain where it modifies anorexigenic balance. In view of the widespread human exposure to DON, the present results may lead to reconsider the potential consequences of chronic DON consumption on human eating disorders.
Subject(s)
Anorexia/physiopathology , Feeding Behavior/drug effects , Food Contamination , Nerve Net/drug effects , Nerve Net/physiopathology , Trichothecenes/pharmacology , Animals , Brain Stem/drug effects , Brain Stem/metabolism , Brain Stem/physiopathology , Calcium-Binding Proteins/metabolism , Cervical Vertebrae/drug effects , Cervical Vertebrae/metabolism , Cervical Vertebrae/surgery , DNA-Binding Proteins/metabolism , Darkness , Humans , Immunohistochemistry , Injections, Intraventricular , Male , Mice , Nerve Tissue Proteins/metabolism , Neurons/drug effects , Neurons/metabolism , Nucleobindins , Phenotype , Pro-Opiomelanocortin/metabolism , Proto-Oncogene Proteins c-fos/metabolism , Trichothecenes/administration & dosage , VagotomyABSTRACT
Deoxynivalenol (DON), one of the most abundant trichothecenes found on cereals, has been implicated in mycotoxicoses in both humans and farm animals. Low-dose toxicity is characterized by reduced weight gain, diminished nutritional efficiency, and immunologic effects. The levels and patterns of human food commodity contamination justify that DON consumption constitutes a public health issue. DON stability during processing and cooking explains its large presence in human food. We characterized here DON intoxication by showing that the toxin concomitantly affects feeding behavior, body temperature, and locomotor activity after both per os and central administration. Using c-Fos expression mapping, we identified the neuronal structures activated in response to DON and observed that the pattern of neuronal populations activated by the toxin resembled those induced by inflammatory signals. By real-time PCR, we report the first evidences for a DON-induced central inflammation, attested by the strong upregulation of interleukin-1ß, interleukin-6, tumor necrosis factor-α, cyclooxygenase-2, and microsomal prostaglandin synthase-1 (mPGES-1) messenger RNA. However, silencing prostaglandins E2 signaling pathways using mPGES-1 knockout mice, which are resistant to cytokine-induced sickness behavior, did not modify the responses to the toxin. These results reveal that, despite strong similarities, behavioral changes observed after DON intoxication differ from classical sickness behavior evoked by inflammatory cytokines.
