Erfani Marjan, Ghazi Tabatabaei Zohreh, Sadigh-Eteghad Saeed, Farokhi-Sisakht Fatemeh, Farajdokht Fereshteh, Mahmoudi Javad, Karimi Pouran, Nasrolahi Ava
Neurosciences Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
Higher Education Institute of Rab-Rashid, Tabriz, Iran.
Exp Physiol. 2019 Oct;104(10):1544-1554. doi: 10.1113/EP087535. Epub 2019 Aug 11.
What is the central question of this study? Heat stress has harmful effects on the brain structure and synaptic density via induction of oxidative stress and neuroinflammation, which result in neuronal damage in the hippocampus and thereby cognitive impairments. In this study, we investigate the effect of Rosa canina treatment on cognitive function in heat stress-exposed rats and its underlying mechanisms. What is the main finding and its importance? We show that R. canina improves cognitive deficits induced by heat stress by attenuation of oxidative stress and neuroinflammation and by upregulation of synaptic proteins in the hippocampus.
The aim of the study was to evaluate the effects of aqueous methanolic extract of Rosa canina (RC) dried fruits on oxidative stress, inflammation, synaptic degeneration and memory dysfunction induced by heat stress (HS) in rats. Sixty adult male Wistar rats were randomly divided into five groups as follows: the control group received normal saline (NS); the HS group was exposed to heat stress (43°C) for 15 min once a day for 2 weeks; and HS+R groups were exposed to heat stress and received one of three doses (250, 500 or 1000 mg kg ) of RC methanolic extract for 2 weeks. A passive avoidance test and a Y-maze test were performed to assess learning and memory. The levels of reactive oxygen species were assessed. The serum cortisol concentration and hippocampal total antioxidant capacity, superoxide dismutase and glutathione peroxidase were also detected using spectrophotometry. The protein expressions of c-Fos, heat-shock protein-70, tumour necrosis factor-α, growth-associated protein 43, post-synaptic density-95 and synaptophysin were evaluated in the hippocampal tissue. The results showed that RC significantly improved cognitive dysfunction induced by HS, which was accompanied by downregulation of tumour necrosis factor-α and upregulation of growth-associated protein 43 and synaptophysin proteins in the hippocampus of HS-exposed rats. Furthermore, RC significantly attenuated serum cortisol concentrations and upregulated heat shock protein-70 and c-Fos in the hippocampus. In addition, the administration of RC attenuated reactive oxygen species levels and enhanced antioxidant defense in the hippocampus. These findings indicate that RC attenuated the deleterious effect of HS on cognition through its antioxidant properties and by enhancing synaptic function and plasticity.
本研究的核心问题是什么？热应激通过诱导氧化应激和神经炎症对脑结构和突触密度产生有害影响，进而导致海马体中的神经元损伤，从而造成认知障碍。在本研究中，我们调查了犬蔷薇治疗对热应激暴露大鼠认知功能的影响及其潜在机制。主要发现及其重要性是什么？我们发现犬蔷薇通过减轻氧化应激和神经炎症以及上调海马体中的突触蛋白来改善热应激诱导的认知缺陷。
本研究旨在评估犬蔷薇（RC）干果的甲醇水提取物对大鼠热应激（HS）诱导的氧化应激、炎症、突触退化和记忆功能障碍的影响。60只成年雄性Wistar大鼠随机分为五组，如下：对照组接受生理盐水（NS）；热应激组每天暴露于热应激（43°C）15分钟，持续2周；热应激+RC组暴露于热应激并接受三种剂量（250、500或1000mg/kg）之一的RC甲醇提取物，持续2周。进行被动回避试验和Y迷宫试验以评估学习和记忆。评估活性氧水平。还使用分光光度法检测血清皮质醇浓度以及海马体总抗氧化能力、超氧化物歧化酶和谷胱甘肽过氧化物酶。在海马组织中评估c-Fos、热休克蛋白-70、肿瘤坏死因子-α、生长相关蛋白43、突触后密度-95和突触素的蛋白表达。结果表明，RC显著改善了HS诱导的认知功能障碍，这伴随着热应激暴露大鼠海马体中肿瘤坏死因子-α的下调以及生长相关蛋白43和突触素蛋白的上调。此外，RC显著降低血清皮质醇浓度并上调海马体中的热休克蛋白-70和c-Fos。此外，给予RC可降低海马体中的活性氧水平并增强抗氧化防御。这些发现表明，RC通过其抗氧化特性以及增强突触功能和可塑性减轻了HS对认知的有害影响。
