Metabolic Profiling in Blastocoel Fluid and Blood Plasma of Diabetic Rabbits

Abstract

Metabolic disorders of the mother adversely affect early embryo development, causing changes in maternal metabolism and consequent alterations in the embryo environment in the uterus. The goal of this study was to analyse the biochemical profiles of embryonic fluids and blood plasma of rabbits with and without insulin-dependent diabetes mellitus (DT1), to identify metabolic changes associated with maternal diabetes mellitus in early pregnancy. Insulin-dependent diabetes was induced by alloxan treatment in female rabbits 10 days before mating. On day 6 post-coitum, plasma and blastocoel fluid (BF) were analysed by ultrahigh performance liquid chromatography-tandem mass spectroscopy (UPLC-MS/MS) (Metabolon Inc. Durham, NC, USA). Metabolic datasets comprised a total of 284 and 597 compounds of known identity in BF and plasma, respectively. Diabetes mellitus had profound effects on maternal and embryonic metabolic profiles, with almost half of the metabolites changed. As predicted, we observed an increase in glucose and a decrease in 1,5-anhydroglucitol in diabetic plasma samples. In plasma, fructose, mannose, and sorbitol were elevated in the diabetic group, which may be a way of dealing with excess glucose. In BF, metabolites of the pentose metabolism were especially increased, indicating the need for ribose-based compounds relevant to DNA and RNA metabolism at this very early stage of embryo development. Other changes were more consistent between BF and plasma. Both displayed elevated acylcarnitines, body3-hydroxybutyrate, and multiple compounds within the branched chain amino acid metabolism pathway, suggesting that lipid beta-oxidation is occurring at elevated levels in the diabetic group. This study demonstrates that maternal and embryonic metabolism are closely related. Maternal diabetes mellitus profoundly alters the metabolic profile of the preimplantation embryo with changes in all subclasses of metabolites.

Fatty Acid Profile of Blood Plasma at Mating and Early Gestation in Rabbit

“…The absence or low concentration of short and medium FA, docohexaenoic and adrenic acid agrees with the findings of other studies [ 23 ].…”

Embryonic diapause due to high glucose is related to changes in glycolysis and oxidative phosphorylation, as well as abnormalities in the TCA cycle and amino acid metabolism

“…The source of glucose in follicular fluid is plasma ( 58 , 59 ) and metabolites found in the blood of a diabetic mother are transferred to the follicular fluid through the vascular theca. And the concentration of glucose in mouse fallopian tube fluid is similar to that in serum glucose ( 60 ). In addition, the metabolites in the blastocoel fluid correlate closely with that in the maternal blood ( 61 , 62 ).…”

Identification of the Inner Cell Mass and the Trophectoderm Responses after an In Vitro Exposure to Glucose and Insulin during the Preimplantation Period in the Rabbit Embryo

“…Increased glucose and insulin concentrations are reflected in oviductal and uterine fluids [ 9 , 11 ]. Preimplantation embryos are responsive to glucose and insulin through the activation of signaling and metabolic pathways [ 14 , 15 , 41 , 42 , 43 ]. The preimplantation period corresponds to a critical window of susceptibility during which variations in the environment can have a major impact on the offspring.…”