Division of Anatomy and Neurobiology, Faculty of Medicine, Medical University of Gdańsk, Dębinki 1, 80-211, Gdańsk, Poland.
Division of Medical Laboratory Diagnostics - Fahrenheit Biobank BBMRI.pl, Medical University of Gdańsk, Dębinki 1, 80-211, Gdańsk, Poland.
Cell Mol Neurobiol. 2023 Nov;43(8):4245-4259. doi: 10.1007/s10571-023-01415-8. Epub 2023 Oct 6.
Hypercholesterolemia affects the neurovascular unit, including the cerebral blood vessel endothelium. Operation of this system, especially in the context of energy metabolism, is controlled by extracellular concentration of purines, regulated by ecto-enzymes, such as e-NTPDase-1/CD39, ecto-5'-NT/CD73, and eADA. We hypothesize that hypercholesterolemia, via modulation of the activity of nucleotide metabolism-regulating ecto-enzymes, deteriorates glycolytic efficiency and energy metabolism of endothelial cells, which may potentially contribute to development of neurodegenerative processes. We aimed to determine the effect of hypercholesterolemia on the concentration of purine nucleotides, glycolytic activity, and activity of ecto-enzymes in the murine brain microvascular endothelial cells (mBMECs). We used 3-month-old male LDLR/Apo E double knockout mice to model hypercholesterolemia and atherosclerosis. The age-matched wild-type C57/BL6 mice were a control group. The intracellular concentration of ATP and NAD and extracellular activity of the ecto-enzymes were measured by HPLC. The glycolytic function of mBMECs was assessed by means of the extracellular acidification rate (ECAR) using the glycolysis stress test. The results showed an increased activity of ecto-5'-NT and eADA in mBMECs of the hypercholesterolemic mice, but no differences in intracellular concentration of ATP, NAD, and ECAR between the hypercholesterolemic and control groups. The changed activity of ecto-5'-NT and eADA leads to increased purine nucleotides turnover and a shift in their concentration balance towards adenosine and inosine in the extracellular space. However, no changes in the energetic metabolism of the mBMECs are reported. Our results confirm the influence of hypercholesterolemia on regulation of purine nucleotides metabolism, which may impair the function of the cerebral vascular endothelium. The effect of hypercholesterolemia on the murine brain microvascular endothelial cells (mBMECs). An increased activity of ecto-5'-NT and eADA in mBMECs of the LDLR/Apo E mice leads to a shift in the concentration balance towards adenosine and inosine in the extracellular space with no differences in intracellular concentration of ATP. Figure was created with Biorender.com.
高胆固醇血症影响神经血管单元，包括脑血管内皮细胞。该系统的运作，特别是在能量代谢的背景下，由细胞外嘌呤浓度控制，受细胞外酶调节，如 e-NTPDase-1/CD39、ecto-5'-NT/CD73 和 eADA。我们假设高胆固醇血症通过调节核苷酸代谢调节细胞外酶的活性，降低内皮细胞的糖酵解效率和能量代谢，这可能潜在地导致神经退行性过程的发展。我们旨在确定高胆固醇血症对小鼠脑微血管内皮细胞 (mBMEC) 中嘌呤核苷酸浓度、糖酵解活性和细胞外酶活性的影响。我们使用 3 个月大的 LDLR/ApoE 双敲除小鼠来模拟高胆固醇血症和动脉粥样硬化。年龄匹配的野生型 C57/BL6 小鼠作为对照组。通过 HPLC 测量细胞内 ATP 和 NAD 浓度以及细胞外酶的活性。通过糖酵解应激试验测量 mBMEC 的细胞外酸化率 (ECAR) 来评估糖酵解功能。结果显示，高胆固醇血症小鼠的 mBMEC 中ecto-5'-NT 和 eADA 的活性增加，但高胆固醇血症组和对照组之间细胞内 ATP、NAD 和 ECAR 没有差异。ecto-5'-NT 和 eADA 活性的改变导致嘌呤核苷酸周转率增加，细胞外空间中腺苷和肌苷的浓度平衡向它们转移。然而，mBMECs 的能量代谢没有变化。我们的结果证实了高胆固醇血症对嘌呤核苷酸代谢调节的影响，这可能损害脑血管内皮细胞的功能。高胆固醇血症对小鼠脑微血管内皮细胞 (mBMEC) 的影响。LDLR/ApoE 小鼠的 mBMEC 中ecto-5'-NT 和 eADA 的活性增加导致细胞外空间中腺苷和肌苷的浓度平衡向它们转移，而细胞内 ATP 浓度没有差异。图由 Biorender.com 创建。
