Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan, Republic of China.
Laboratory for Neuron-Glia Circuitry, RIKEN Center for Brain Science , Wako, Saitama , Japan.
Am J Physiol Endocrinol Metab. 2019 Apr 1;316(4):E622-E634. doi: 10.1152/ajpendo.00408.2018. Epub 2019 Jan 22.
Excessive maternal high-fructose diet (HFD) during pregnancy and lactation has been reported to cause metabolic disorders in the offspring. Whether the infant's brain metabolism is disturbed by maternal HFD is largely unknown. Brain energy metabolism is elevated dramatically during fetal and postnatal development, whereby maternal nutrition is a key factor that determines cellular metabolism. Astrocytes, a nonneuronal cell type in the brain, are considered to support the high-energy demands of neurons by supplying lactate. In this study, the effects of maternal HFD on astrocytic glucose metabolism were investigated using hippocampal primary cultures of female infants. We found that glycolytic capacity and mitochondrial respiration and electron transport chain were suppressed by maternal HFD. Mitochondrial DNA copy number and mitochondrial transcription factor A expression were suppressed by maternal HFD. Western blots and immunofluorescent images further indicated that the glucose transporter 1 was downregulated whereas the insulin receptor-α, phospho-insulin receptor substrate-1 (Y612) and the p85 subunit of phosphatidylinositide 3-kinase were upregulated in the HFD group. Pioglitazone, which is known to increase astrocytic glucose metabolism, effectively reversed the suppressed glycolysis, and lactate release was restored. Moreover, pioglitazone also normalized oxidative phosphorylation with an increase of cytosolic ATP. Together, these results suggest that maternal HFD impairs astrocytic energy metabolic pathways that were reversed by pioglitazone.
孕期和哺乳期母体高果糖饮食(HFD)已被报道可导致后代代谢紊乱。母体 HFD 是否会干扰婴儿的大脑代谢在很大程度上尚不清楚。胎儿和产后发育期间大脑能量代谢显著升高,而母体营养是决定细胞代谢的关键因素。星形胶质细胞是大脑中的一种非神经元细胞类型,被认为通过供应乳酸来支持神经元的高能量需求。在这项研究中,使用雌性婴儿的海马原代培养物研究了母体 HFD 对星形胶质细胞葡萄糖代谢的影响。我们发现母体 HFD 抑制了糖酵解能力和线粒体呼吸及电子传递链。线粒体 DNA 拷贝数和线粒体转录因子 A 的表达也受到母体 HFD 的抑制。Western blot 和免疫荧光图像进一步表明,在 HFD 组中葡萄糖转运蛋白 1 下调,而胰岛素受体-α、磷酸化胰岛素受体底物-1(Y612)和磷脂酰肌醇 3-激酶的 p85 亚基上调。吡格列酮已知可增加星形胶质细胞的葡萄糖代谢,可有效逆转糖酵解的抑制,并恢复乳酸的释放。此外,吡格列酮还可通过增加细胞溶质 ATP 使氧化磷酸化正常化。总之,这些结果表明母体 HFD 损害了星形胶质细胞的能量代谢途径,而吡格列酮可逆转这一损伤。