Antioxidant extract counteracts the effects of aging on cortical spreading depression and oxidative stress in the brain cortex

Abstract Purpose: To investigate the effects of Murici extract on the brain excitability-dependent phenomenon known as cortical spreading depression (CSD) and on brain oxidative stress. Methods: Adult and aged Wistar rats were supplemented with murici extract (150 mg/kg/day or 300 mg/kg/day) by gavage for fifteen days. Afterwards, the animals were submitted to a CSD electrophysiological recording and to brain oxidative stress evaluation. Results: Our results showed that aging decreased CSD propagation velocity, catalase activity and glutathione/oxidized glutathione ratio (GSH/GSSG) in the brain cortex of the rats, and increased malondialdehyde (MDA) concentrations and superoxide dismutase (SOD) activity. The highest dose (300 mg/kg/day) of murici extract accelerated CSD, whereas the lowest (150mg/kg/day) decelerated, in both adult and aged animals. In contrast, aged animals supplemented with murici extract in both doses presented low MDA levels and high GSG/GSSG ratio in comparison to the control-aged animals. Conclusion: Murici extract supplementation seems to revert detrimental effects in aged brains and could be considered as a strategy in the treatment of pathologies related to aging and cortical spreading depression.

摘要
研究目的：探讨穆里西提取物（Murici extract）对脑兴奋性依赖性现象——皮层扩散性抑制（cortical spreading depression, CSD）以及脑氧化应激的影响。
研究方法：对成年及老年Wistar大鼠以灌胃方式连续15天给予穆里西提取物，给药剂量分别为150 mg/kg/天与300 mg/kg/天。随后对大鼠实施皮层扩散性抑制电生理记录及脑氧化应激水平评估。
研究结果：本研究结果显示，衰老可降低大鼠大脑皮层的皮层扩散性抑制传播速度、过氧化氢酶（catalase）活性以及谷胱甘肽/氧化型谷胱甘肽比值（GSH/GSSG），同时升高丙二醛（malondialdehyde, MDA）含量与超氧化物歧化酶（superoxide dismutase, SOD）活性。在成年与老年大鼠中，高剂量（300 mg/kg/天）穆里西提取物可加速皮层扩散性抑制进程，低剂量（150 mg/kg/天）则延缓该进程。与之相比，给予两种剂量穆里西提取物的老年大鼠体内丙二醛水平更低，谷胱甘肽/氧化型谷胱甘肽比值显著高于老年对照组大鼠。
研究结论：穆里西提取物干预似乎可逆转老年大脑的损伤性改变，有望作为治疗衰老相关疾病及皮层扩散性抑制相关病症的潜在策略。