Unraveling hepatic consequences of intrauterine growth restriction and catch- up growth: Insights from histological, biochemical, and metabolomic analysis in rats Running title: Hepatic Metabolomics and Intrauterine Growth Retardation

Abstract

Intrauterine growth restriction (IUGR) is increasingly recognized as a significant risk factor for metabolic disorders in adulthood. Employing a multi-faceted approach encompassing histopathological, immunohistochemical, biochemical, Western-blotting, and metabolomics analyses, the study aimed to elucidate potential metabolite markers of IUGR, and catch-up growth-related metabolic disturbances and the underlying metabolic pathways implicated in IUGR pathogenesis. This study cohort comprised 54 male siblings from 20 Sprague-Dawley female young rats. On the 19th day of gestation, half of the pregnant rats underwent bilateral uterine artery ligation, while the remaining half underwent a simulated surgical intervention involving solely peritoneal incisions. Blood and liver samples were collected from the pups after attaining catch-up growth at the postnatal weeks 2, 4, and 8. IUGR rats exhibited a spectrum of changes including histological abnormalities, altered apoptosis rates, oxidative stress markers, and mitochondrial energy metabolism. Metabolomic analysis revealed dysregulation, in multiple metabolic pathways encompassing galactose, propanoate, glycerolipid, cysteine, methionine, and tyrosine metabolism, among others. Notably, disturbances were observed in butanoate, glutathione metabolism, valine, leucine, and isoleucine biosynthesis and degradation, citrate cycle, aminoacyl-tRNA biosynthesis, as well as glycolysis/gluconeogenesis. Our metabolomics analysis provides insights into the potential disease susceptibility of individuals born with IUGR, including obesity, diabetes, heart failure, cancer, mental retardation, kidney and liver diseases, and cataracts. These findings underscore the intricate interplay between intrauterine conditions and long-term metabolic health outcomes, highlighting the need for further investigation into preventive and therapeutic strategies aimed at mitigating the risk of metabolic diseases in individuals with a history of IUGR. Formun Üstü