Large scale studies of the influence of GMO-based corn diet after 6 months of consumption in Wistar rats

International audienceWistar rats were fed during 6 months with 33% maize, either non genetically modified or containing MON810 or NK603 (11% and 33%). Extensive chemical analysis by MS and NMR profiling and targeted analyses were undertaken to qualify the harvests and quantify in maize and pellets macro- and micronutrients, anti-nutrients and undesirable substances and contaminants. All diets contained low levels (50 to 100 fold lower than the MRL values) of undesirable substances. Thirty rats per gender were fed with 8 different diets: MON810 (11% and 33%) plus isogenic control, NK603 (11% and 33% ± glyphosate treatment) and isogenic control. Rats were sacrificed after 3 months (sub-group A, 10 rats per diet, per gender) and 6 months (sub-group B, 12 rats and C, 8 rats per diet, per gender). Urine were collected in metabolic cages and blood at 90 (sub-group A), 90/135/180 (sub-group B) and 180 days of feeding (sub-group C). In addition to classical toxicological analysis we performed metabolomics and hormones quantification in blood and urine, transcriptomics on liver and kidney, gut barrier analysis, kidney and gonads targeted immunohistology. Statistical analyses were conducted first blindly and thereafter on the basis of relevant pair-wise comparison. We easily discriminate the rat gender or maize origin. Among the numerous statistically significant differences in pair-wise comparisons some concerned GMO and non-GMO, but no biological relevance could be established due to the lack of differences in biologically linked variables, dose-response effects or clinical disorders