WD16-1
Memory enhancement by oral administration of the extract of Eleutherococcus senticosus leaves and active compounds transferred in the brain
エゾウコギ葉水エキス経口投与による記憶向上作用と脳に移行する活性成分の同定
Yamauchi Yui（山内 唯）1，葛 躍偉2，吉松 嘉代3，小松 かつ子2，東田 千尋1
1Division of Neuromedical Science, Institute of Natural Medicine, University of Toyama, Toyama, Japan
2Division of Pharmacognosy, Institute of Natural Medicine, University of Toyama, Toyama, Japan
3Reseach Center for Medicinal Plant Resources, National Institutes of Biomedical Innovation, Health and Nutrition, Ibaraki, Japan
Eleutherococcus senticosus (ES) rhizome is used as a crude drug, shigoka. In contrast, pharmaceutical function of leaves of ES has not been paid attention. We were interested in different varieties of constituents between rhizomes and leaves, and expected to find some pharmacological effects of ES leaves. This study aimed to investigate the effect of ES leaves on cognitive function.The extract of ES leaves was p.o. administered to normal mice (ddY, 7-weeks old, male) for 26 days. Treatment with the extract significantly enhanced object recognition memory. In the brain of extract-treated mice, axonal density was increased. To identify compounds transferred in the brain, the plasma and cerebral cortex were isolated after p.o. administration of ES leaves extract. As a result, eleven compounds in the plasma, and five compounds in the cortex were identified. Among brain penetrating compounds, ciwujianoside C3, eleutheroside M and ciwujianoside B were investigated further. All three compounds significantly enhanced object recognition memory in normal mice (ddY, 7-weeks old, male) by p.o. administration. Those compounds showed axonal and dendritic growth effect in cultured cortical neurons.Our study showed that the extract of ES leaves enhanced object recognition memory in normal mice, and identified brain penetrating active compounds, ciwujianoside C3, eleutheroside M and ciwujianoside B. It is interesting to reveal the signaling mechanism of each three compounds. In addition, those compounds could be functional substances of ES leaves extract. This study may contribute to future developing ES leaves extract as a new botanical drug. | | WD16-2
Antidepressant effect of resolvin E1 in chronic pain model mice
慢性痛モデルマウスにおけるレゾルビンE1の抗うつ効果
Otsuka Takahisa（大塚 貴尚），鈴木 博惠，佐藤 孝行，人羅 菜津子，南 雅文
Department of Pharmacology, Graduate School of Pharmaceutical Sciences Hokkaido University Sapporo Japan
We previously reported that resolvin E1 (RvE1) and resolvin E2, bioactive lipid mediators generated from n-3 polyunsaturated fatty acid eicosapentaenoic acid (EPA), produce antidepressant effects in a murine lipopolysaccharide (LPS)-induced depression model. Since comorbidity of chronic pain and depression has been recognized in the clinic, and several preclinical studies have reported depression-like behaviors in animal models of chronic pain, in this study, we examined the effect of RvE1 on depression-like behaviors caused by chronic pain. A spared nerve injury (SNI) model was used as a chronic pain model. Six weeks old male BALB/c mice underwent SNI surgery. The tibial and common personeal nerves were tightly ligated with 5.0 silk and cut distal to the ligation. Two weeks after the surgery, a tail suspension test (TST) was carried out. Immobility time was significantly increased in the SNI group, compared to the sham group. Intracerebroventricular (i.c.v.) injection of RvE1 (1 ng) decreased the immobility time in the SNI group, but not in the sham group. Since RvE1 is reported to act on ChemR23 as an agonist, we tested the effect of chemerin, a ChemR23 agonist, on SNI-induced depression-like behaviors. I.c.v. injection of chemerin (500 ng) decreased immobility. These results suggest that RvE1 produces an antidepressant effect on pain-associated depression-like behaviors likely through ChemR23. |
