摘要
Background： The importance of non-glucose carbohydrates, especially mannose and inositol, for normal development is increasingly recognized. Whether pregnancies complicated by abnormal glucose transfer to the fetus also affect the regulation of non-glucose carbohydrates is unknown. In pregnant sheep, maternal insulin infusions were used to reduce glucose supply to the fetus for both short （2-wk） and long （8-wk） durations to test the hypothesis that a maternal insulin infusion would suppress fetal mannose and inositol concentrations. We also used direct fetal insulin infusions （1-wk hyperinsulinemic-isoglycemic clamp） to determine the relative importance of fetal glucose and insulin for regulating non-glucose carbohydrates. Results： A maternal insulin infusion resulted in lower maternal （50%, P 〈 0.01） and fetal （35-45%, P 〈 0.01） mannose concentrations, which were highly correlated （r^2 = 0.69, P 〈 0.01）. A fetal insulin infusion resulted in a 50% reduction of fetal mannose （P 〈 0.05）. Neither maternal nor fetal plasma inositol changed with exogenous insulin infusions. Additionally, maternal insulin infusion resulted in lower fetal sorbitol and fructose （P 〈 0.01）. Conclusions： Chronically decreased glucose supply to the fetus as well as fetal hyperinsulinemia both reduce fetal non-glucose carbohydrates. Given the role of these carbohydrates in protein glycosylation and lipid production, more research on their metabolism in pregnancies complicated by abnormal glucose metabolism is clearly warranted.
Background： The importance of non-glucose carbohydrates, especially mannose and inositol, for normal development is increasingly recognized. Whether pregnancies complicated by abnormal glucose transfer to the fetus also affect the regulation of non-glucose carbohydrates is unknown. In pregnant sheep, maternal insulin infusions were used to reduce glucose supply to the fetus for both short （2-wk） and long （8-wk） durations to test the hypothesis that a maternal insulin infusion would suppress fetal mannose and inositol concentrations. We also used direct fetal insulin infusions （1-wk hyperinsulinemic-isoglycemic clamp） to determine the relative importance of fetal glucose and insulin for regulating non-glucose carbohydrates. Results： A maternal insulin infusion resulted in lower maternal （50%, P 〈 0.01） and fetal （35-45%, P 〈 0.01） mannose concentrations, which were highly correlated （r^2 = 0.69, P 〈 0.01）. A fetal insulin infusion resulted in a 50% reduction of fetal mannose （P 〈 0.05）. Neither maternal nor fetal plasma inositol changed with exogenous insulin infusions. Additionally, maternal insulin infusion resulted in lower fetal sorbitol and fructose （P 〈 0.01）. Conclusions： Chronically decreased glucose supply to the fetus as well as fetal hyperinsulinemia both reduce fetal non-glucose carbohydrates. Given the role of these carbohydrates in protein glycosylation and lipid production, more research on their metabolism in pregnancies complicated by abnormal glucose metabolism is clearly warranted.
基金
supported by National Institutes of Health training grant T32 HD007186-32 (W Hay, PI and PD)
supported by NIH Grants R01DK088139 and K08HD060688
American Diabetes Association Junior Faculty Award 7-08-JF-51(PJR, PI)
provided by the UC Denver DERC (P30DK57516
J. Hutton, PI)
supported as a Scholar by NIH Building Interdisciplinary Careers in Women ’ s Health Scholar Award K12HD057022 (J. Regensteiner, PI)
a Children ’ s Hospital Colorado Research Institute Research Scholar Award (PI)
supported by NIH K01DK090199 (PI) and as a trainee on NIH training grant T32 HD007186-32 (W Hay, PI and PD)
