Xu Yan, Hu Rong, He Duanqun, Zhou Guijuan, Wu Heng, Xu Chenlin, He Bing, Wu Lin, Wang Yilin, Chang Yunqian, Ma Rundong, Xie Ming, Xiao Zijian
The First Affiliated Hospital, University of South China, Hengyang, China.
Xiangdong Hospital Hunan Normal University, Zhuzhou, China.
Brain Behav. 2020 Jul;10(7):e01655. doi: 10.1002/brb3.1655. Epub 2020 May 22.
Alzheimer's disease (AD) is a progressive neurodegenerative disease. It can lead to progressive cognitive impairment, memory loss, and behavioral alterations. So far, the exact cellular and molecular mechanisms underlying this disorder remain unclear. And there are no effective treatments to prevent, halt, or reverse AD. In recent years, Chinese traditional medicine has become a new force in the treatment of AD, and the typical representatives of natural herbal ingredients are curcumin and its derivatives. Bisdemethoxycurcumin (BDMC), which is a classical derivative of curcumin, was found to have neuroprotective effects against a cell model of Alzheimer's disease (AD) in our previous studies. This study investigated the intrinsic mechanism of BDMC against AD in animal models.
In this study, BDMC was injected into the lateral ventricles of normal C57BL/6 mice, APP/PS mice, and APP/PS mice treated with EX527 (the inhibitor of SIRT1). Y maze and Morris water maze were used to test the learning and memory ability of mice. Nissl staining was used to observe the morphological changes of neurons. Immunofluorescence staining was used to detect Aβ deposition in mice. The activities of GSH and SOD were determined to observe the levels of oxidative stress in mice. And Western blot analyses were used to detect content of SIRT1 in mice.
In the APP/PS mice, after BDMC intervention, their cognitive function improved, oxidative stress adjusted, the number of neurons increased, Aβ deposition decreased, and the level of SIRT1 expression increased. However, when SIRT1 is inhibited, BDMC on the improvement in the learning and memory ability and the improvement on oxidative stress in APP/PS1 mice were reversed.
Our findings demonstrated that in the AD mice, BDMC has antagonistic effect on AD. And an intermediate step in the antagonism effect is caused by SIRT1 upregulation, which leading to decreased oxidative stress. Based on these, we concluded that BDMC injection into the lateral ventricle can act against AD by upregulating SIRT1 to antioxidative stress.
阿尔茨海默病(AD)是一种进行性神经退行性疾病。它可导致进行性认知障碍、记忆力丧失和行为改变。迄今为止,这种疾病的确切细胞和分子机制仍不清楚。并且尚无有效的治疗方法来预防、阻止或逆转AD。近年来,中药已成为治疗AD的一股新力量,天然草药成分的典型代表是姜黄素及其衍生物。双去甲氧基姜黄素(BDMC)是姜黄素的一种经典衍生物,在我们之前的研究中发现其对阿尔茨海默病(AD)细胞模型具有神经保护作用。本研究调查了BDMC在动物模型中对抗AD的内在机制。
在本研究中,将BDMC注射到正常C57BL/6小鼠、APP/PS小鼠以及用EX527(SIRT1抑制剂)处理的APP/PS小鼠的侧脑室中。采用Y迷宫和莫里斯水迷宫测试小鼠的学习和记忆能力。采用尼氏染色观察神经元的形态变化。采用免疫荧光染色检测小鼠脑中的Aβ沉积。测定谷胱甘肽(GSH)和超氧化物歧化酶(SOD)的活性以观察小鼠的氧化应激水平。并采用蛋白质免疫印迹分析检测小鼠脑中SIRT1的含量。
在APP/PS小鼠中,BDMC干预后,其认知功能得到改善,氧化应激得到调节,神经元数量增加,Aβ沉积减少,SIRT1表达水平升高。然而,当SIRT1被抑制时,BDMC对APP/PS1小鼠学习记忆能力的改善作用以及对氧化应激的改善作用均被逆转。
我们的研究结果表明,在AD小鼠中,BDMC对AD具有拮抗作用。并且这种拮抗作用的一个中间步骤是由SIRT1上调引起的,从而导致氧化应激降低。基于这些,我们得出结论,向侧脑室注射BDMC可通过上调SIRT1来对抗氧化应激从而对抗AD。