Delayed administration of Trichilia catigua A. Juss. Ethyl-acetate fraction after cerebral ischemia prevents spatial memory deficits, decreases oxidative stress, and impacts neural plasticity in rats
Delayed administration of Trichilia catigua A. Juss. Ethyl-acetate fraction after cerebral ischemia prevents spatial memory deficits, decreases oxidative stress, and impacts neural plasticity in rats
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DOI：
10.1016/j.jep.2023.116176
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发表时间：
2023-01-21
影响因子：
5.4
通讯作者：
Milani, Humberto
中科院分区：
文献类型：
--
作者：
de Oliveira, Daniela Velasquez;Godinho, Jacqueline;Milani, Humberto
民族药理相关性：巴西民间医学中使用毛眼蜂Trichilia catigua A.Juss(梅花科)缓解疲劳和情绪压力，改善记忆。我们实验室以前的研究报告说，在脑缺血前给予体内卡提瓜的乙酸乙酯部分(EAF)可以防止记忆丧失，减少氧化应激和神经炎症。尽管这些发现对卡提瓜的神经保护作用有价值，但在缺血之前或之后立即给予的治疗限制了其临床疗效。因此，尚不清楚T.catigua在给药后缺血时是否具有特定的疗效时间窗(TWE)。研究目的：鉴于先前研究的连续性，我们调查了如果在缺血后不同的有效时间窗开始治疗，卡提瓜虫的EAF是否保持其神经保护特性。材料和方法：建立大鼠短暂性全脑缺血(TGCI)模型，于缺血后1、4、6h分别单次灌胃给予EAF(400 mg/kg)或赋形剂(1ml/kg)。测定缺血后1d血清中PCG、GSH、GSSG蛋白含量及超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活性，作为氧化应激指标。在另一项实验中，幼龄大鼠在放射状迷宫任务中进行空间学习训练，然后接受TGCI。延迟治疗在4或6小时后开始，并持续7天。对脑缺血后10、17和24天的逆行记忆能力进行评估。随后，检查了大脑中海马区和大脑皮层的神经元退行性变和神经元树突形态。另一组在再灌流4h后接受EAF，4d后检测脑组织中GFAP和Iba-1的免疫反应。结果：单次给药1、4、6h可减轻缺血所致的氧化应激，表现为PCG和GSSG含量减少，GSH/GSSG比值恢复，GSH/GSSG比值恢复正常。缺血导致持续性记忆丧失(即，健忘症)，这种结果一直可以通过在缺血后4或6小时开始的EAF治疗而得到改善。EAF治疗延迟4h对缺血存活神经元的树突形态有积极影响。TGCI可降低海马区和大脑皮层中BDNF、SYN、PSD-95和NeuN的蛋白水平。电弧炉使SYN和PSD-95蛋白水平正常化。结论：本研究证实了先前证实黄连具有神经保护作用的数据，并扩展了这些数据，显示延迟给药可有效防止记忆障碍，减少氧化应激、树突退化和突触蛋白丢失，持续时间为1-6h。这种特殊的双黄连在临床前研究中可能具有临床意义，提示该植物可能用于开发神经保护策略在缺血性脑病的背景下。本研究的另一个创新发现是卡提瓜可能具有神经营养/神经整形的特性。
Ethnopharmacological relevance: Trichilia catigua A. Juss (Meliaceae) is used in Brazilian folk medicine to alleviate fatigue and emotional stress and improve memory. Previous studies from our laboratory reported that an ethyl-acetate fraction (EAF) of T. catigua that was given before cerebral ischemia in vivo prevented memory loss and reduced oxidative stress and neuroinflammation. Despite the value of these findings of a neuroprotective effect of T. catigua, treatment that was given immediately before or immediately after ischemia limits its clinical rele-vance. Thus, unknown is whether T. catigua possesses a specific time window of efficacy (TWE) when admin-istered postischemia. Aim of the study: Given continuity to previous studies, we investigated whether an EAF of T. catigua maintains its neuroprotective properties if treatment begins at different time windows of efficacy after ischemia. We also evaluated, for the first time, whether T. catigua possesses neuroplasticity/neurotrophic properties.Material and methods: Rats were subjected to transient global brain ischemia (TGCI) and then given a single dose of the EAF (400 mg/kg) or vehicle (1 ml/kg) orally 1, 4, or 6 h postischemia. The levels of protein PCG, GSH, and GSSG, and activity of SOD and CAT were assayed as markers of oxidative stress on the day after ischemia. In another experiment, naive rats underwent spatial learning training in a radial maze task and then subjected to TGCI. Delayed treatment with the EAF began 4 or 6 h later and continued for 7 days. Retrograde memory performance was assessed 10, 17, and 24 days postischemia. Afterward, brains were examined for neuro-degeneration and neuronal dendritic morphology in the hippocampus and cerebral cortex. Another group received the EAF at 4 h of reperfusion, and 4 days later their brains were examined for GFAP and Iba-1 immunoreactivity. Lastly, ischemic rats received the EAF 4 h after ischemia and neural plasticity-related pro-teins, BDNF, SYN, PSD 95, and NeuN were measured in the hippocampus 7 and 14 days after ischemia.Results: A single EAF administration 1, 4, or 6 h postischemia alleviated oxidative stress that was caused by ischemia, expressed as a reduction of the amount of the PCG and GSSG, normalization of the GSH/GSSG ratio, and the restoration of SOD activity. Ischemia caused the persistent loss of memory (i.e., amnesia), an outcome that was consistently ameliorated by treatment with the EAF that was initiated 4 or 6 h postischemia. The 4 h delay in EAF treatment positively impacted dendritic morphology in neurons that survived ischemia. TGCI reduced BDNF, SYN, PSD-95, and NeuN protein levels in the hippocampus and cerebral cortex. The EAF normalized SYN and PSD-95 protein levels. Ischemia-induced neurodegeneration and glial cell activation were not prevented by EAF treatment.Conclusion: The present study corroborates prior data that demonstrated the neuroprotective potential of T. catigua and extends these data by showing that the delayed administration of EAF postischemia effectively prevented memory impairment and decreased oxidative stress, dendritic deterioration, and synaptic protein loss within a TWE that ranged from 1 to 6 h. This specific TWE in preclinical research may have clinical relevance by suggesting the possible utility of this plant for the development of neuroprotective strategies in the setting of ischemic brain diseases. Another innovative finding of the present study was the possible neurotrophic/neuro-plastic properties of T. catigua.