Geriatric Anesthesia Research Unit, Massachusetts General Hospital and Harvard Medical School, 149 13th St., Room 4310, Charlestown, MA 02129-2060, USA.
Anesth Analg. 2011 Dec;113(6):1468-75. doi: 10.1213/ANE.0b013e31822e913c. Epub 2011 Sep 29.
β-Amyloid protein (Aβ) accumulation and caspase activation have been shown to contribute to Alzheimer disease neuropathogenesis. Aβ is produced from amyloid precursor protein through proteolytic processing by aspartyl protease β-site amyloid precursor protein-cleaving enzyme (BACE). The inhaled anesthetic isoflurane has been shown to induce caspase activation and increase levels of BACE and Aβ. However, the underlying mechanisms and interventions of the isoflurane-induced neurotoxicity remain largely to be determined. The glucose analog 2-deoxy-d-glucose (2-DG) has neuroprotective effects. Therefore, we sought to determine whether 2-DG can reduce caspase-3 activation and the increase in the levels of BACE and reactive oxygen species (ROS) induced by isoflurane.
H4 human neuroglioma cells were treated with saline or 2-DG (5 mM) for 1 hour followed by a control condition or 2% isoflurane for 6 hours. The levels of caspase-3 cleavage (activation), BACE, cytosolic calcium, and ROS were determined. Two-way analysis of variance was used to assess the interactions of 2-DG and isoflurane on caspase-3 activation, and levels of BACE and ROS.
In H4 human neuroglioma cells, 2-DG reduced the caspase-3 activation (477% vs 186%, F = 8.68; P = 0.019) and the increase in BACE levels (345% vs 123%, F = 42.24; P = 0.0002) induced by isoflurane. 2-DG decreased the levels of cytosolic calcium and ROS (100% vs 66%, F = 1.94; P = 0.014).
These results suggest that 2-DG may decrease oxidative stress and increase cytosolic calcium levels, thus attenuating isoflurane-induced neurotoxicity.
β-淀粉样蛋白(Aβ)的积累和半胱天冬酶的激活已被证明与阿尔茨海默病的神经发病机制有关。Aβ 通过天冬氨酸蛋白酶β-位淀粉样前体蛋白裂解酶(BACE)的蛋白水解加工从淀粉样前体蛋白中产生。吸入麻醉剂异氟烷已被证明可诱导半胱天冬酶的激活,并增加 BACE 和 Aβ 的水平。然而,异氟烷诱导的神经毒性的潜在机制和干预措施在很大程度上仍有待确定。葡萄糖类似物 2-脱氧-D-葡萄糖(2-DG)具有神经保护作用。因此,我们试图确定 2-DG 是否可以减少异氟烷诱导的 caspase-3 激活以及 BACE 和活性氧(ROS)水平的增加。
用生理盐水或 2-DG(5 mM)处理 H4 人神经胶质瘤细胞 1 小时,然后进行对照或 2%异氟烷处理 6 小时。测定 caspase-3 切割(激活)、BACE、细胞质钙和 ROS 的水平。采用双因素方差分析评估 2-DG 和异氟烷对 caspase-3 激活以及 BACE 和 ROS 水平的相互作用。
在 H4 人神经胶质瘤细胞中,2-DG 降低了异氟烷诱导的 caspase-3 激活(477%对 186%,F=8.68;P=0.019)和 BACE 水平的增加(345%对 123%,F=42.24;P=0.0002)。2-DG 降低了细胞质钙和 ROS 的水平(100%对 66%,F=1.94;P=0.014)。
这些结果表明,2-DG 可能通过降低氧化应激和增加细胞质钙水平来减轻异氟烷诱导的神经毒性。