The effect of crocin on memory, hippocampal acetylcholine level, and apoptosis in a rat model of cerebral ischemia.

Although the memory- improving effect of crocin has been suggested by previous evidences, the association between this effect and hippocampal acetylcholine (Ach) level and apoptosis is not well investigated. This study aimed to determine the protective effects of crocin on memory, hippocampal Ach level, and apoptosis in a rat model of cerebral ischemia. Male Wistar rats were divided into sham group received saline, and other 3 groups underwent 4-vessel occlusion brain ischemia (4VOI), received oral administration of either saline or crocin in doses of 30 mg/day and 60 mg/day for 7 days. Outcomes were memory, determined by radial eight-arm maze (RAM) task and Morris water maze (MWM) test, Ach release in the dorsal hippocampus (evaluated by microdialysis-HPLC) and apoptosis (investigated by TUNEL assay). 4VOI impaired memory reduced dorsal hippocampus Ach level, and induced apoptosis. Crocin, significantly improved the memory (F = 343.20; P < 0.001 for RAM error choices and F = 182.5; P < 0.0001 for MWM), increased Ach level (F = 115.1; P < 0.001) and prevented hippocampal neuronal apoptosis (W = 183.50; P < 0.001) as compared statistically by ANOVA test. Crocin can be suggested as a promising therapy for ischemic cerebrovascular accidents by its memory preserving, Ach-increasing, and neuroprotective effects.

Baicalein exerts neuroprotective effect against ischaemic/reperfusion injury via alteration of NF-kB and LOX and AMPK/Nrf2 pathway.

ischaemic stroke accounts for almost 11% of all deaths worldwide and has a high incidence of permanent disability among patients. Baicalein has many beneficial pharmacological properties, including anti-inflammatory and anti-oxidant effects. However, the neuroprotective effect of baicalein is still unclear. The current study scrutinizes the neuroprotective effect of baicalein against the ischaemic/reperfusion (I/R) injury via alteration of the nuclear factor kappa B (NF-kB) and AMP-activated protein kinase/nuclear factor erythroid 2-related factor 2 AMPK/Nrf2 signaling pathway. Wistar rats were used for the current study. In rats, I/R injury was caused by transient occlusion of the middle cerebral artery for 1 h accompanied by reperfusion for 24 h. The rats were divided into different groups and treated with the different doses of baicalein (2.5, 5 and 10 mg/kg). The effects of baicalein on the murine neurological function were determined via infarct volume, neurological defect scores, and brain water content. The -inflammatory cytokines and oxidative stress were estimated in the region of the cortical along with the expression of apoptosis markers, such as B-cell lymphoma 2, Bax, and caspase-3. Quantitative reverse transcription polymerase chain reaction was used for the estimation of the NF-kB, cyclooxygenase-2 (COX-2), prostaglandin E2 (PGE2) and lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) expression. Baicalein significantly (p < 0.001) ameliorated the infarction volume, brain water content, and neurological outcome, and the malondialdehyde level, and reduced the level of interleukin-1ß, interleukin-6, tumor necrosis factor-α, superoxide dismutase, glutathione, and catalase in a dose-dependent manner. Baicalein significantly (p < 0.001) altered the expression of COX-2, PGE2, LOX-1 and NF-kB as compared to I/R control group rats. Baicalein significantly reduced the Nrf2 and AMPK levels, and protected the rat brain against the I/R injury, suggesting a neuroprotective effect via down-regulation of NF-kB and LOX-1 expression and the AMPK/Nrf2 pathway.