A proteomic-based approach to study underlying molecular responses of the small intestine of Wistar rats to genetically modified corn (MON810)

Abstract

A genetically modified (GM) commercial corn variety, MON810, resistant to European corn borer, has been shown to be non-toxic to mammals in a number of rodent feeding studies carried out in accordance with OECD Guidelines. Insect resistance results from expression of the Cry1Ab gene encoding an insecticidal Bt protein that causes lysis and cell death in susceptible insect larvae by binding to midgut epithelial cells, which is a key determinant of Cry toxin species specificity. Whilst whole animal studies are still recognised as the ‘gold standard’ for safety assessment, they only provide indirect evidence for changes at the cellular/organ/tissue level. In contrast, omics-based technologies enable mechanistic understanding of toxicological or nutritional events at the cellular/receptor level. To address this important knowledge-gap and to gain insights into the underlying molecular responses in rat to MON810, differential gene expression in the epithelial cells of the small intestine of rats fed formulated diets containing MON810, its near isogenic line, two conventional corn varieties, and a commercial (Purina™) corn-based control diet were investigated using comparative proteomic profiling. Pairwise and five-way comparisons showed that the majority of proteins that were differentially expressed in the small intestine epithelial cells in response to consumption of the different diets in both 7-day and 28-day studies were related to lipid and carbohydrate metabolism and protein biosynthesis. Irrespective of the diet, a limited number of stress-related proteins were shown to be differentially expressed. However these stress-related proteins differed between diets. No adverse clinical or behavioural effects, or biomarkers of adverse health, were observed in rats fed GM corn compared to the other corn diets. These findings suggest that MON810 has negligible effects on the small intestine of rats at the cellular level compared with the well-documented toxicity observed in susceptible insects.Electronic supplementary materialThe online version of this article (10.1007/s11248-019-00157-y) contains supplementary material, which is available to authorized users.

Expression profiling of key pathways in rat liver after a one-year feeding trial with transgenic maize MON810

“…The different feeds used in this study had been chosen as they have highly similar nutrient contents, so that it is unlikely that a difference based on the nutritional values has affected the study. Further, variations in the expression of stress-related proteins have recently been described in a proteomic analysis of the rat small intestine after a 7-day and 28-day feeding regime with 33% corn; however, this occurred when rats were fed transgenic (including MON810) or non-transgenic corn varieties and could therefore not be attributed to the transgenic corn diet 42 . Therefore, the underlying reason for our finding still remains to be elucidated.…”

Legal regulation in the field of genetically modified organisms (GMO) turnover in Russia and foreign countries

“…Решение на выдачу разрешения на генную модификацию данной линии сосны было принято с учетом того, что законодательно эта проблема не была урегулирована. Стоит сказать, что некоторые исследовательские группы планируют культивировать ГМпчел, кораллы, насекомых и другие объекты, подлежащие генной модификации (Al-Harbi, Lary & Edwards, et al, 2019;Makarova, Khromov & Spechenkova, et al, 2019;Waltz, 2015;Tudisco, et al, 2015;Plavec & Berlec, 2020) 11 . Заметим, что в отношении кукурузы были проведены эксперименты, результатами которых явилось то, что «…в 2012 г. была разрешена к использованию Bt-кукуруза с синтетическим геном eCry3.1Ab, кодирующим химерный белок с активными центрами токсинов Cry3A и Cry1Ab, что позволяет ему поражать личинок как Жесткокрылых, так и Чешуекрылых.…”

“…В то время как британский законодатель в целом исповедует осторожный и ограничительный подход к вопросам нормативного регулирования ГМО, британское общество в своем большинстве не возражает против ГМ-продукции, при условии, что она безвредна для здоровья человека и окружающей среды, однако так было не всегда. В начале 1990-х годов в стране проходили массовые протесты против культивирования ГМО-культур (Davison & Bertheau, 2008), но постепенно общество стало относится к ГМО терпимее.…”

Chronic Toxicity of Genetically Modified Maize with Cry1Ab-ma Gene and Its Effect on Serum Metabolites in Rats

“…An omics-based tool can examine early metabolite alterations and offer proof at the molecular level . The benefits of using the omics-based tool to investigate the safety of GM maize have already been demonstrated .…”

“…An omics-based tool can examine early metabolite alterations and offer proof at the molecular level. 10 The benefits of using the omics-based tool to investigate the safety of GM maize have already been demonstrated. 11 In our study, nontargeted metabolomics was used to assess the different metabolites in the abdominal aortic serum of rats.…”