Protein O-GlcNAcylation levels are regulated independently of dietary intake in a tissue and time-specific manner during rat postnatal development

Abstract

Aim: Metabolic sources switch from carbohydrates in utero, to fatty acids after birth and then a mix once adults. O-GlcNAcylation (O-GlcNAc) is a post-translational modification considered as a nutrient sensor. The purpose of this work was to assess changes in protein O-GlcNAc levels, regulatory enzymes and metabolites during the first periods of life and decipher the impact of O-GlcNAcylation on cardiac proteins. Methods: Heart, brain and liver were harvested from rats before and after birth (D-1 and D0), in suckling animals (D12), after weaning with a standard (D28) or a low-carbohydrate diet (D28F), and adults (D84). O-GlcNAc levels and regulatory enzymes were evaluated by western blots. Mass spectrometry (MS) approaches were performed to quantify levels of metabolites regulating O-GlcNAc and identify putative cardiac O-GlcNAcylated proteins. Results: Protein O-GlcNAc levels decrease drastically and progressively from D-1 to D84 (13-fold, P