Long-term phenotypic effects following vitrified-thawed embryo transfer in a rabbit model

Abstract

2223 Since the first human was conceived through in vitro fertilisation in 1978, over 6.5 24 million babies have been born by assisted reproductive technologies (ARTs).25 Although most ART babies and children seem healthy, in recent years several 26 studies have evidenced a potential impact of ARTs on long-term development 27 and health. Herein, we have developed an animal model to determine whether 28 vitrified embryo transfer procedure induces phenotypic changes over the growth 29 performance and in the complementary transcriptomic and proteomic analyses 30 at hepatic level. To this end, 2 populations were developed; vitrified embryos 31 transferred to the surrogate mothers (VT) and naturally conceived animals (NC).32 After delivery, animals were weighed weekly from 1 to 20 weeks of age. In 33 adulthood, animals were euthanized and organs were harvested and weighed.34 After that, liver tissue was used to identify changes in the transcriptomic and 35 proteomic profile. At adulthood, VT group showed significant lower body, liver 36 and heart weight. After functional analysis of RNA-Seq data, a subset of 96 37 differentially expressed transcripts in VT animal were related to alteration in zinc 38 homeostasis, lipid metabolism, and hepatic immune pathways. After proteomic 39 analysis, a subset of 76 differentially expressed proteins also revealed some 40 disturbed metabolic pathways related with the lipid and glycan metabolism, and 41 an impaired oxidative metabolism related to ATP synthesis in the mitochondria.42 Current findings suggest that progeny derived after transfer of vitrified embryos 43 have long-term consequences on growth rate and vital organs weights in 44 adulthood, correlated with molecular signatures at transcriptomic and proteomic 45 level of hepatic tissue. 3 46 47 48 Introduction 49 50Since the first human conceived through in vitro fertilisation in 1978, it has been 51 estimated that more than 6.5 million babies born by assisted reproductive 52 technologies (ARTs, [1]). Nevertheless, from the beginning of the application of 53 ARTs, there has been concern about the influence of these technologies on 54 development, and in consequence several epidemiological studies have reported 55 on this issue, associating ARTs with low birth weight, preterm birth, heart disease, 56 hypertension, hyperlipidaemia, insulin resistance and increased risk of type 2 57 diabetes or adverse neurodevelopmental outcome [1][2][3][4][5]. However, it is difficult to 58 determine in humans whether these effects are really caused by ARTs per se or 59 originate from either genetic abnormalities or risk factors intrinsic to infertile 60 patients [4]. Based on animal models that avoid these confounding factors, 61 analogous effects have been reported, evidencing long-lasting consequences of 62 ARTs such as glucose intolerance, insulin resistance, cardiometabolic disorders, 63 hypertension, behavioural deficits, memory loss, abnormal hepatic and fat 64 metabolomes, placenta dysfunction, body weight and organ weight changes, 65 ...