Luteolin (LUT) is a flavonoid compound in Flos Lonicerae Japonicae and Scutellaris baicalensis Georgi and has a wide range of anti-oxidative, anti-inflammatory, and neuroprotective effects. This study was investigated the effects of LUT on learning and memory impairment induced by permanent bilateral common carotid artery occlusion (pBCAO) in rats. LUT was administered orally once a day (30 mg/kg) for 28 days starting at 4 weeks after the pBCAO. The acquisition of learning and the retention of memory were tested on 9th week after the pBCAO using the Morris water maze. In addition, effects of AST on oxidative damage were evaluated with levels of superoxide dismutase (SOD) and malondialdehyde (MDA) and expressions of 4-hydroxynonenal (4HNE) and 8-hydroxy-2'-deoxy-guanosine (8-OHdG) in the brain tissue of rat which was performed the Morris water maze test.
The results are as followings;
1. LUT significantly shortened the escape latencies on the 3rd day of acquisition training trials.
2. LUT significantly prolonged the swimming time spent in the target and peri-target zones and significantly reduced the swimming time spent in zones far from the target.
3. LUT significantly shortened the time for the 1st target heading in the retention test.
4. LUT significantly increased the % swim in the targer area in the retention test.
5. LUT significantly increased the memory score in the retention test,
6. LUT significantly increased the down-regulated SOD level in the cerebral cortex.
7. LUT significantly attenuated the up-regulation of MDA level in the hippocampus.
8. LUT significantly attenuated the up-regulation of 4HNE expression in the CA1 of hippocampus.
9. LUT significantly attenuated the up-regulation of 8-OHdG expression in the CA1 of hippocampus.
The results suggest that LUT exert ameliorating effect on memory impairment through inhibition of oxidative damage in brain tissue and may be a beneficial medicinal compound to treat cognitive impairment and neurodegenerative diseases.