An official website of the United States government.
<p>Objective 1: Develop data for use in risk assessment of mycotoxins in human and animal health.</p> <p>Objective 2: Establish integrated strategies to manage and reduce mycotoxin contamination in cereals and in forages.</p> <p> Objective 3. Better Understand the Biology and Ecology of Mycotoxigenic Fungi.</p>
IA will use the K562 human erythroleukemia cell line as a model to evaluate Systemic Acquired Resistance (SAR) of deoxynivalenol (DON), its major metabolites and other trichothecenes. Growth of this cell line is inhibited by DON, in a manner similar to inhibition of mouse splenocyte proliferation in vivo, according to preliminary data from Iowa. This model may be used as a biologically relevant screening assay for DON-contaminated grain and food samples; 24 h incubation of K562 cells with grain extracts containing known amounts of DON cause cell proliferation inhibition identical to the same amount of pure DON. This cell system will also be used to model human tissue contents of trichothecenes, by comparing individual mycotoxin dose/responses with various combinations of trichothecenes and their key metabolites.Rodents will be used as a model for carcinogenicity, teratogenicity and immunotoxicity for the fumonisins and DON. Since several trichothecenes have been identified by Centers for Disease Control as biosecurity risks, it is critical to be able to use animal assays in conjunction with cell systems to evaluate potential natural or intentional contamination of feeds and foods by these agents. Animal assays will be critical to Iowa in assessing if the decontamination and detoxification strategies designed in objective 2 are successful. We will continue to assess acute toxicity of fumonisins and DON in mouse and other animal models in oral feeding studies with naturally contaminated foods or purified toxin. Adaptation to subchronic exposures to DON is a key observation in previous studies (IA) that we will assess further by studying DON metabolites and DON-metabolizing gut microbial changes over time and dose of DON.IA will assess distillers grains for mycotoxins using high-performance liquid chromatography (HPLC), and evaluate effects of genetically engineered maize varieties on mycotoxin formation, using a combination of natural observation and mycotoxin spiking during ethanol production.IA will evaluate fungal population diversity, especially for fumonisin producing species, and assess in the field and in laboratory conditions, how co-contamination by diverse fungal species affects fumonisin (FB) production, using polymerase chain reaction (PCR) and other genetic methods to identify fungal species and HPLC to assess mycotoxin loads in maize.