Transcriptomic investigations on pig livers treated with steroid esters

Growth promoting agents in food producing animals are banned in the European Union to protect consumers' health. Among them, steroid hormones support protein synthesis contributing to muscle hypertrophy and fat loss. For this reason they are exploited to improve meat features reducing production times and costs. In some non-european countries they are largely adopted, moreover they are approved by the U.S. Food and Drug Administration and even recommended to be more sustainable with less environmental impact. But there are sure side effects that impair both animal and human health. In the EU, official controls by competent authorities inspect meat products, both marketed within the European Community and imported from Third Countries, to detect residues of these unauthorised drugs. National Residues Control Plans still detect these compounds. Therefore, the setup of alternative and/or complementary methods is becoming essential to further unveil such illicit practices. In the proposed study, we analysed the coding RNA to identify specific perturbations related to the administration of testosterone and nandrolone esters in the liver of fattening pigs. RNAseq analysis highlighted a cluster of 491 genes with a significant (p<0.05) differential expression when comparing the treated groups with the control group. Through a selection process, we finally recognize a set of 16 genes that successfully discriminate between control and treated groups. The quantification of selected transcriptional biomarkers could represent a novel diagnostic approach for screening purposes, able to identify animals suspected of illicit treatments and to address further confirmatory analysis where needed.