An integrated in silico/in vitro approach to assess the xenoestrogenic potential of Alternaria mycotoxins and metabolites

Xenoestrogenic mycotoxins may contaminate food and feed posing a public health issue. Besides the zearalenone group, the Alternaria toxin alternariol (AOH) has been described as a potential mycoestrogen. However, the estrogenicity of Alternaria toxins is still largely overlooked and further data are needed to better describe the group toxicity. In the frame of risk assessment, mixed in silico/in vitro approaches already proved to be effective first-line analytical tools. An integrated in silico/in vitro approach was used to investigate the effects of metabolic and chemical modifications on the estrogenicity of AOH. Among the considered modifications, methylation was found critical for enhancing estrogenicity (as seen for alternariol monomethyl ether (AME)) while hydroxylation and glucuronidation had the opposite effect (as seen for 4-hydroxy AOH and 4-hydroxy AME). The structure-activity relationship analysis provided the structural rationale. Our results provide insights to design more efficient risk assessment studies expanding knowledge over the group toxicity.