Dastgerdi Azadehalsadat Hosseini, Radahmadi Maryam, Pourshanazari Ali Asghar, Dastgerdi Hajaralsadat Hosseini
Department of Physiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
Adv Biomed Res. 2017 Dec 26;6:157. doi: 10.4103/abr.abr_107_17. eCollection 2017.
Chronic stress adversely influences brain functions while crocin, as an effective component of saffron, exhibits positive effects on memory processes. This study investigated the effects of different doses of crocin on the improvement of learning and memory as well as corticosterone (CORT) levels in the hippocampus and frontal cortex of rats subjected to chronic stress.
Forty male rats were randomly allocated to five different groups ( = 8): Control, sham; stress (6 h/day for 21 days) groups, and two groups receiving daily intraperitoneal injections of one of two doses (30 and 60 mg/kg) of crocin accompanied by 21 days of restraint stress. Latency was evaluated as a brain function using the passive avoidance test before and one-day after a foot shock. CORT levels were measured in the homogenized hippocampus and frontal cortex.
Results revealed that chronic stress had a significantly ( < 0.01) negative effect on memory. Crocin (30 and 60 mg/kg), however, gave increase to significantly ( < 0.01 and < 0.05; respectively) improved memory functions in the stressed rats. Furthermore, the CORT levels in the hippocampus and frontal cortex declined significantly ( < 0.05) in the stress group compared to the control. Only a crocin dose of 30 mg/kg was observed modulate significantly ( < 0.05) the CORT levels in the hippocampus and frontal cortex in the stressed group.
It was found that the lower crocin dose (30 mg/kg) had more beneficial effects than its higher (60 mg/kg) dose on learning and memory under chronic stress conditions. Moreover, it was speculated that different doses of crocin act on different neurotransmitters and biochemical factors in the brain.
慢性应激会对脑功能产生不利影响，而藏红花素作为藏红花的有效成分，对记忆过程具有积极作用。本研究调查了不同剂量的藏红花素对慢性应激大鼠学习和记忆改善以及海马体和额叶皮质中皮质酮（CORT）水平的影响。
40只雄性大鼠被随机分为五个不同组（每组 = 8只）：对照组、假手术组；应激组（每天6小时，持续21天），以及两组在21天的束缚应激期间每天腹腔注射两种剂量（30和60毫克/千克）藏红花素中的一种。在足部电击前和电击后一天，使用被动回避试验评估潜伏期作为脑功能。在匀浆后的海马体和额叶皮质中测量CORT水平。
结果显示，慢性应激对记忆有显著（<0.01）负面影响。然而，藏红花素（30和60毫克/千克）分别使应激大鼠的记忆功能显著改善（分别为<0.01和<0.05）。此外，与对照组相比，应激组海马体和额叶皮质中的CORT水平显著下降（<0.05）。仅观察到30毫克/千克剂量的藏红花素能显著调节（<0.05）应激组海马体和额叶皮质中的CORT水平。
发现在慢性应激条件下，较低剂量的藏红花素（30毫克/千克）对学习和记忆的有益作用比其较高剂量（60毫克/千克）更大。此外，推测不同剂量的藏红花素作用于大脑中的不同神经递质和生化因子。
