Uso dos genes Bmp4, Egr3 e Hsp70 como possíveis marcadores de toxicidade embrionária

Abstract

Animal models remain relevant in scientific research because they allow the integrated investigation of physiological and pathological processes. Their use must be based on ethical and scientific criteria, considering the suitability of the model to the study objectives. Therefore, research should encourage the adoption of alternative methods, such as the use of embryos, which contribute to reducing the number of animals used, enable less invasive experimental approaches, and, whenever feasible, promote the partial or total replacement of animal use, in accordance with the principles of the 3 R’s (Reduction, Refinement, and Replacement). In this study, 33 Mus musculus embryos at the two-cell stage were exposed in vitro to the herbicides Pendimethalin and Prowl®H2O, with the aim of evaluating morphological alterations up to the blastocyst stage through in house and Gardner’s classification, based on the degree of blastocyst expansion and the quality of the inner cell mass (ICM) and the trophectoderm (TE), as well as changes in the expression of the genes Bmp4, Egr3, and Hsp70 using the RT-qPCR technique. Morphological analysis revealed developmental delay, cellular fragmentation, and cytoplasmic vacuolization, with more pronounced effects observed in the group exposed to Prowl®H2O. Molecular analysis demonstrated a significant increase in Bmp4 expression in the group treated with Prowl®H2O, while Egr3 and Hsp70 showed higher expression in embryos exposed to Pendimethalin, suggesting the activation of cellular stress pathways and dysregulation of developmental processes. These results indicate that both the isolated active ingredient and the commercial formulation can induce early morphological and molecular alterations, highlighting the importance of the integrated evaluation of morphological and molecular parameters in toxicity studies.