Toshihiko Hanawa

I.c.v. administration of orexin-A induces an antidepressive-like effect through hippocampal cell proliferation.

A decrease in orexin-A (OX-A) levels has been reported to be associated with depression. It is also well known that stress and depression can disrupt neurogenesis in the dentate gyrus of the hippocampus; however, it is unclear how OX-A is involved in depression and/or neurogenesis. In the present study, we investigated the effect of i.c.v. administration of OX-A on the forced swimming test (FST), an accepted behavioral screen of antidepressant-like activity, and on the cell proliferation with bromodeoxyuridine (BrdU) in the dentate gyrus at 4 days after i.c.v. administration of OX-A. OX-A administration (140 pmol/mouse) led to a significant reduction in animal immobility in the FST, without affecting spontaneous locomotor activities or serum corticosterone levels. In addition, the number of BrdU-positive cells in the dentate gyrus was significantly increased in OX-A-treated mice in vivo; however, OX-A did not affect the percentage of doublecortin-positive cells in the dentate gyrus. The proliferation of neural progenitor cells derived from rat fetal brain was not affected by OX-A treatment in vitro, and the orexin receptor 1 (OXR1) protein was not expressed in these cells. Treatment with the OXR1 antagonist SB-334867 (30 mg/kg, i.p.) blocked both the OX-A-induced decrease in the immobility of FST and increase in BrdU-positive. Moreover, the OX-A-induced increase in neuropeptide Y (NPY)-positive cells in the hilus of the dentate gyrus was blocked by SB-334867. These results suggest that OX-A induces an antidepressive-like effect, at least in part, via the enhancement of cell proliferation in the dentate gyrus. These effects of OX-A also may be partly relevant to the regulation of the NPY system in the hilus of the dentate gyrus.

Antidepressant-like Effect of l-perillaldehyde in Stress-induced Depression-like Model Mice through Regulation of the Olfactory Nervous System

Perillae Herba (a leaf of Perilla frutescens) has been prescribed as one of the component herbs in certain Kampo (Japanese herbal) medicines that are used clinically for the improvement of depressive mood. l-Perillaldehyde (PAH) is a major component in the essential oil containing in Perillae Herba, but its antidepressant-like effect has not been reported. To clarify the antidepressant-like effect of PAH, the inhaled effect of PAH on stress-induced depression-like model mice prepared by subjection to a combination of forced swimming and chronic mild stresses was investigated. The degree of the depression-like state was measured by the animals duration of immobility using a forced swimming test. Inhalation of PAH (0.0965 and 0.965 mg/mouse/day, 9 days) significantly shortened the duration of immobility of the depression-like model mice and did not affect locomotor activity. However, another odor substance, cinnamaldehyde containing in Cinnamomi Cortex, exhibited no reduction in the immobility. The reduction in the immobility induced by the inhalation of PAH was prevented on anosmia-induced mice prepared by intranasal irrigation with zinc sulfate. These results suggest that the inhalation of PAH shows antidepressant-like activity through the olfactory nervous function.

Daikenchuto, a traditional Japanese herbal medicine, ameliorates postoperative ileus by anti-inflammatory action through nicotinic acetylcholine receptors

BackgroundDaikenchuto (DKT), a gastrointestinal prokinetic Japanese herbal medicine, is prescribed for patients with postoperative ileus (POI) and adhesive bowel obstruction following abdominal surgery. Several mechanisms for the amelioration of POI by DKT have been suggested; however, it has remained unclear whether DKT shows anti-inflammatory effects in POI. In the present study, we investigated the effects of DKT in a mouse POI model and attempted to clarify the detailed mechanisms of action.MethodIntestinal manipulation (IM) was applied to the distal ileum of mice. DKT was administered orally to the animals 4 times before and after IM. Gastrointestinal transit in vivo, leukocyte infiltration, cytokine mRNA expression and gastrointestinal motility were analyzed. We also investigated the effects of the α7nAChR antagonist methyllycaconitine citrate (MLA) on the DKT-mediated ameliorative action against POI, and we studied the effects of DKT on inflammatory activity in α7nAChR knockout mice.ResultsDKT treatment led to recovery of the delayed intestinal transit induced by IM. DKT significantly inhibited the infiltration of neutrophils and CD68-positive macrophages, and inhibited mRNA expressions of TNF-α and MCP-1. MLA significantly reduced the anti-inflammatory action of DKT, and the amelioration of macrophage infiltration by DKT was partially suppressed in α7nAChR knockout mice.ConclusionsIn conclusion, in addition to the gastrointestinal prokinetic action, DKT serves as a novel therapeutic agent for POI characterized by its anti-inflammatory potency. The DKT-induced anti-inflammatory activity may be partly mediated by activation of α7nAChR.

Anxiolytic effect of Kami-Shoyo-San (TJ-24) in mice Possible mediation of neurosteroid synthesis

We assessed the anxiolytic effect of Kami-Shoyo-San (Jia-wei-xiao-yao-san; TJ-24), one of a traditional Chinese herbal medicine used for the treatment of menopausal anxiety, by the social interaction (SI) test in male mice. Acute administration of TJ-24 (25-100 mg/kg, p.o.), as well as the gamma-amino-butyric acidA/benzodiazepine (GABA(A)/BZP) receptor agonist diazepam (1-3 mg/kg, i.p.), dose dependently increased the SI time, respectively. The GABA(A) receptor antagonist picrotoxin blocked the effects of TJ-24 and diazepam. TJ-24-induced SI behavior was significantly blocked by the GABA(A)/BZP receptor inverse agonist Ro 15-4513 and the GABA(A)/BZP receptor antagonist flumazenil. In addition, 5alpha-reductase inhibitor finasteride potently blocked the effect of TJ-24 without attenuating the basal level by itself. These findings suggest that TJ-24 shows the anxiolytic effect through the neurosteroid synthesis followed by GABA(A)/BDZ receptor stimulations.

Stimulating Effect of Japanese Herbal (Kampo) Medicine, Hochuekkito on Upper Respiratory Mucosal Immune System

Japanese herbal (Kampo) medicine, Hochuekkito (Bu-Zhong-Yi-Qi-Tang in Chinese, TJ-41) and Juzentaihoto (Shi-Quan-Da-Bu-Tang in Chinese, TJ-48) are well-known Kampo formulas used as tonic. Although these medicines have separately been applied to the patients clinically depending on their symptoms, the differences of the pharmacological activities for these medicines have not been fully understood. TJ-48 and TJ-41 were compared for their effects on antibody response in upper respiratory mucosal immune system in vivo. Oral administration of TJ-41 (100 mg kg−1 per day) to early aged BALB/c mice, which were nasally sensitized with influenza hemagglutinin vaccine, significantly enhanced influenza virus-specific IgA and IgG antibody titers in nasal cavity and sera, respectively. However, oral administration of TJ-48 (100 mg kg−1 per day) failed to show the enhancing activity. TJ-41 increased not only influenza virus-specific IgA antibody titer but also total IgA antibody titer in nasal cavity. The stimulating activity of TJ-41 disappeared after treatment with methotrexate. The present study strongly suggests that TJ-41 can stimulate the mucosal immune system of upper respiratory tract, and results in enhancement of antigen-specific antibody response in upper respiratory mucosal and systemic immune systems.

The efficacy of goshuyuto, a typical Kampo (Japanese herbal medicine) formula, in preventing episodes of headache.

ABSTRACT Objective: The purpose of this clinical trial was to assess the efficacy of goshuyuto, a typical Kampo formula, in preventing episodes of headache in chronic headache patients. Research design and methods: Because the treatment target of a Kampo formula is decided on a basis different to that of Western medicine, we first selected patients belonging to a subgroup that responded to goshuyuto before conducting the usual randomized controlled trial. During stage 1, the subjects were instructed to orally consume goshuyuto for 4 weeks. Only those subjects judged as responders advanced to stage 2, during which a double-blind, randomized, placebo-controlled study was conducted. The subjects consumed the same dose of goshuyuto or placebo for 12 weeks. Results: Of the 91 subjects enrolled in stage 1, 60 were judged as responders. Of these, 53 advanced to stage 2; 28 were assigned to the goshuyuto group and 25 to the placebo group. The decrease in the number of days on which headache episodes occurred was greater in the goshuyuto group than in the placebo group (2.6 ± 3.7 vs. 0.3 ± 4.0 days, p = 0.034); no difference was observed with regard to the reduction in the frequency of consuming reliever medications (2.2 ± 4.0 vs. 1.4 ± 8.2, p = 0.672). Improvement in the associated symptoms was observed in more than 50% of the subjects in the goshuyuto group. Conclusion: Goshuyuto is useful in preventing episodes of headache in chronic headache patients. Responder-limited design is a candidate for evaluating Kampo medicine.

Effect of orally administered Hochu-ekki-to, a Japanese herbal medicine, on contact hypersensitivity caused by repeated application of antigen

The effects of oral administration of Hochu-ekki-to (HET; bu-zhong-yi-qi-tang in Chinese), a traditional Japanese and Chinese herbal medicine, on chronic contact hypersensitivity were investigated. HET suppressed ear swelling due to chronic contact hypersensitivity caused by repeated application of 2,4,6-trinitro-1-chlorobenzene (TNCB). HET significantly suppressed not only increases in hapten-specific immunoglobulin E (IgE) and IgG1 titer due to repeated application of TNCB, but also total IgE and IgG1 concentration in the serum. Interleukin 4 (IL-4) level in inflamed ear tissue was significantly increased by repeated application of TNCB, and this increase in IL-4 level in the ear was significantly suppressed by oral administration of HET. Interferon gamma (IFN-gamma), IL-2, IL-5, IL-10 and IL-12 levels are not changed as much as IL4 by TNCB and HET did not alter these cytokines as much as IL-4. These results suggest that oral administration of HET suppresses chronic contact hypersensitivity, and it can be assumed that the suppression of serum Ig E and Ig G1 and IL-4 in inflamed ear.

Effects of Kampo medicine, Toki-shakuyaku-san (Tang-Kuei-Shao-Yao-San), on choline acetyltransferase activity and norepinephrine contents in brain regions, and mitogenic activity of splenic lymphocytes in ovariectomized mice.

We investigated the effects of Toki-shakuyaku-san (TSS, Tang-Kuei-Shao-Yao-San in Chinese), Japanese traditional herbal medicine, on the nervous and immune systems in ovariectomized mice as a climacteric disorder model. Female C57BL/6 mice were ovariectomized (OVX) and TSS was given daily through the drinking water for either 10 or 20 days from the day after ovariectomy. After completion of experimental sessions, animals were sacrificed and specific brain regions were assayed for choline acetyltransferase (ChAT) activity and norepinephrine contents. The mitogenic activities, alkaline phosphatase activity and 3-(4, 5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H terazolium bromide (MTT) activity, in splenic lymphocytes has also measured. Furthermore, the effects of TSS on learning and memory ability were studied by the step-through type passive avoidance test. As the results, the administration of TSS significantly suppressed the decrease of ChAT activity in the cerebral cortex (CC) and the dorsal hippocampus (DH) of ovariectomized mice at 10 days after ovariectomy, however no significant effect was observed at 20 days after ovariectomy. Norepinephrine contents in OVX group were decreased at 10 and 20 days after ovariectomy in the CC and the ventral hippocampus (VH). The administration of TSS significantly suppressed the decrease of norepinephrine contents at 20 days after ovariectomy. The mitogenic activities of lymphocyte in spleen were increased at 10 days after ovariectomy, and decreased at 20 days after ovariectomy. However, the suppression of these changes was observed in the group given TSS. The mean latent period was also shortened in the passive avoidance test in the OVX group, but TSS treated group improved mean latency. From these observations, it is inferred that administration of TSS brings on the synthesis of acetylcholine and norepinephrine in the CC and hippocampus, and may improve the memory related behavior and the abnormalities in lymphocytes in the models of the climacteric disorder.

Potentiation of brain acetylcholine neurons by Kami-Untan-To (KUT) in aged mice: Implications for a possible antidementia drug

The effects of a traditional Japanese herbal medicine, Kami-Untan-To (KUT), on brain choline (Ch) and Acetylcholine (ACh) levels in aged mice were examined. Further, the expression of choline acetyltransferase (ChAT) in the medial septum (MS), the vertical limbs of the diagonal band of Broca (VDB), and the nucleus basalis Meynert (NBM) was examined by immunohistochemistry. Following an oral administration of KUT to the aged mice for 3 months, ACh levels in the cortex, striatum and hippocampus were increased significantly. The density of ChAT-immunoreactive cells located in MS, VDB, and NBM in the KUT-treated group was increased significantly as compared to the non-treatment group. The survival rate of aged mice was significantly higher in the KUT-treated group as compared to that in the nontreated group. Our results suggest that KUT potentiates the brain acetylcholinergic system, and may become a possible anti-dementia drug.

Clinical efficacy of Kampo medicine (Japanese traditional herbal medicine) in the treatment of primary dysmenorrhea

Objective:  We intended to evaluate the clinical efficacy of Kampo medicine, a Japanese traditional herbal medicine, for primary dysmenorrhea which was prescribed according to the Kampo diagnosis, with classification of its severity.