Institute of Cerebrovascular Diseases Research and Department of Neurology, Xuanwu Hospital of Capital Medical University, Beijing, China; Dongfang Hospital, Beijing University of Chinese Medicine, Beijing, China.
Institute of Cerebrovascular Diseases Research and Department of Neurology, Xuanwu Hospital of Capital Medical University, Beijing, China.
J Ethnopharmacol. 2019 Jun 28;238:111846. doi: 10.1016/j.jep.2019.111846. Epub 2019 Apr 4.
Huoluo Yinao decoction (HLYND) has been used to ameliorate cognitive impairment induced by chronic cerebral hypoperfusion in clinical for years. However, the exact mechanisms remain unknown.
To investigate the effects and mechanisms underlying HLYND-mediated improvement in cognitive deficits associated with chronic cerebral hypoperfusion.
Thirty-six Sprague-Dawley rats were randomly allocated to three groups: sham, model, and HLYND. Daily administration of HLYND or volume-matched vehicle by gavage was initiated 1 day after bilateral carotid artery stenosis (BCAS) and continued for 42 days. The Morris water maze (MWM) test was used to assess cognitive functions from days 36-42. Via western blot and immunofluorescent staining, restoration of neuronal plasticity and remyelination of white matter were evaluated by analyzing the expression profiles of MAP-2, synaptophysin and MBP. In addition, macrophage/microglial activation was assessed by quantifying changes in Iba1, and macrophage/microglial polarization was assessed by changes in iNOS and CD16 (M1 markers), as well as Arg1 and CD206 (M2 markers).
In the MWM test, BCAS rats showed significantly extended escape latency and reduced platform crossing times, while those in the HLYND group had shortened escape latency and increased frequency of platform crossing. In addition, rats in the model group showed decreased levels and abnormal morphological changes of MAP-2, synaptophysin and MBP, whereas HLYND administration reversed these effects. As expected, Iba1 levels were elevated in both the model and HLYND groups but rats in the model group showed increased levels of the M1 markers, iNOS and CD16, and a correspondent decrease in the M2 marker, Arg1. In contrast, in the HLYND group, iNOS and CD16 levels were suppressed, while Arg1 levels were elevated.
Our findings demonstrate that HLYND mitigates cognitive impairment after chronic cerebral hypoperfusion in rats through mechanisms involving increased neuronal plasticity and white matter remyelination, with a subtile modulation of macrophage/microglial polarization toward the M2 phenotype.
活脑益智汤（HLYND）多年来一直用于改善慢性脑低灌注引起的认知障碍。然而，确切的机制尚不清楚。
探讨 HLYND 改善慢性脑低灌注相关认知功能障碍的作用及机制。
36 只 Sprague-Dawley 大鼠随机分为 3 组：假手术组、模型组和 HLYND 组。双侧颈总动脉狭窄（BCAS）后 1 天开始每天通过灌胃给予 HLYND 或体积匹配的载体，持续 42 天。Morris 水迷宫（MWM）测试用于评估第 36-42 天的认知功能。通过 Western blot 和免疫荧光染色，分析 MAP-2、突触小体蛋白和 MBP 的表达谱，评估神经元可塑性的恢复和白质的髓鞘再生。此外，通过量化 Iba1 的变化来评估巨噬细胞/小胶质细胞的激活，通过 iNOS 和 CD16（M1 标志物）以及 Arg1 和 CD206（M2 标志物）的变化来评估巨噬细胞/小胶质细胞的极化。
在 MWM 测试中，BCAS 大鼠的逃避潜伏期明显延长，平台穿越次数减少，而 HLYND 组的逃避潜伏期缩短，平台穿越次数增加。此外，模型组大鼠 MAP-2、突触小体蛋白和 MBP 的水平降低，形态异常，而 HLYND 给药可逆转这些变化。正如预期的那样，模型组和 HLYND 组的 Iba1 水平均升高，但模型组的 M1 标志物 iNOS 和 CD16 水平升高，M2 标志物 Arg1 水平降低。相比之下，在 HLYND 组中，iNOS 和 CD16 水平受到抑制，而 Arg1 水平升高。
我们的研究结果表明，HLYND 通过增加神经元可塑性和白质髓鞘再生来减轻慢性脑低灌注后大鼠的认知障碍，同时对巨噬细胞/小胶质细胞向 M2 表型的极化进行微妙调节。
