Ouabain regulates kidney metabolic profiling in rat offspring of intrauterine growth restriction induced by low-protein diet

Intrauterine growth restriction (IUGR) can increase the risk of hypertension and kidney disease at adulthood due to fetal programming. In our previous study, we found that supplementation with low concentration of ouabain during pregnancy could restore glomerulus numbers at birth, rescuing kidney development. However, the metabolic pattern of kidney in IUGR offspring and the effect of ouabain have not been evaluated. In this study, based on GC–MS and LC-MS platforms, we used the protein restriction rat model to explore the molecular mechanisms of kidney damage induced by IUGR and the protective effect of ouabain. The results showed that malnutrition could induce IUGR in rat offspring at the 20th gestational day but ouabain treatment could partially reverse the body and kidney weight loss. Ouabain treatment could upregulate arginine, N-acetylornithine and carbamoyl phosphate as well as adenine nucleotide and guanine nucleotide downregulated by low-protein diet. Moreover, six metabolites were identified to be significantly correlated with fetal kidney weight, with 3 metabolites involved in arginine metabolism (arginine, N-acetylornithine, urea) and UDP-glucuronate correlated positively, while lysine and anthranilate correlated negatively. The results suggested that the underlying mechanism of ouabain against renal maldevelopment involved the metabolic regulation, particularly the arginine metabolism, which played an important role in the development of fetal kidney.