Kazuo Toriizuka

Altered Network Topologies and Hub Organization in Adults with Autism: A Resting-State fMRI Study

Recent functional magnetic resonance imaging (fMRI) studies on autism spectrum condition (ASC) have identified dysfunctions in specific brain networks involved in social and non-social cognition that persist into adulthood. Although increasing numbers of fMRI studies have revealed atypical functional connectivity in the adult ASC brain, such functional alterations at the network level have not yet been fully characterized within the recently developed graph-theoretical framework. Here, we applied a graph-theoretical analysis to resting-state fMRI data acquired from 46 adults with ASC and 46 age- and gender-matched controls, to investigate the topological properties and organization of autistic brain network. Analyses of global metrics revealed that, relative to the controls, participants with ASC exhibited significant decreases in clustering coefficient and characteristic path length, indicating a shift towards randomized organization. Furthermore, analyses of local metrics revealed a significantly altered organization of the hub nodes in ASC, as shown by analyses of hub disruption indices using multiple local metrics and by a loss of “hubness” in several nodes (e.g., the bilateral superior temporal sulcus, right dorsolateral prefrontal cortex, and precuneus) that are critical for social and non-social cognitive functions. In particular, local metrics of the anterior cingulate cortex consistently showed significant negative correlations with the Autism-Spectrum Quotient score. Our results demonstrate altered patterns of global and local topological properties that may underlie impaired social and non-social cognition in ASC.

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.

Effect of Shimotsu-to (a Kampo medicine, Si-Wu-Tang) and its constituents on triphasic skin reaction in passively sensitized mice.

Previous studies have reported that mice passively sensitized with anti-DNP (dinitrophenol) IgE antibody exhibited IgE-mediated skin reaction with an immediate phase response (IPR) at 1 h and a late phase response (LPR) at 24 h after the challenge of DNFB (dinitrofluorobenzene). We recently found that a third phase inflammatory reaction with intense and persisting infiltration of eosinophils, named very late phase response (vLPR), was induced by DNFB challenge peaking at 8 days. In this study, we examined the effects of a Kampo medicine, Shimotsu-to (Si-Wu-Tang), and its constituent crude drugs on triphasic skin reaction in passively sensitized mice. Shimotsu-to inhibited ear swelling in LPR and vLPR after DNFB challenge in a dose-dependent manner, and slightly diminished the scratching behavior considered to be associated with pruritus in IPR. The inhibitory effect on LPR and vLPR was partly due to Cnidii Rhizoma (Senkyu) in Shimotsu-to formulation, especially its fraction 5 containing cnidilide. On the other hand, Angelicae Radix (Toki) rather than Cnidii Rhizoma (Senkyu) in Shimotsu-to, inhibited the scratching behavior, although it did not inhibit the ear swelling in IPR. These findings indicate that the Shimotsu-to formulation is useful for the inhibition of cutaneous inflammatory diseases.

The chemical constituents of fresh Gentian Root

We isolated and characterized 23 compounds, including a new iridoid named gentiolutelin and its dimethyl acetal, and a new lignan named gentioluteol from fresh roots (including small amounts of rhizome) of Gentiana lutea cultivated in Japan (Hokkaido). The structures of gentiolutelin and gentioluteol were determined as (1S,2R,3S,5R)-3-hydroxy-2-methyl-5-(2-oxoethyl)-cyclopentanecarboxylic acid methyl ester and (7R,8S,8′S)-4,4′,8,9-tetrahydroxy-3,3′,5-trimethoxy-7,9′-epoxylignan, respectively, on the basis of chemical and spectroscopic evidence. It was noteworthy that gentiopicroside, known to be a major secoiridoid glycoside in Gentian root, was not detected from the fresh roots of 3-year-old G. lutea.

Linked alterations in gray and white matter morphology in adults with high-functioning autism spectrum disorder: A multimodal brain imaging study

Growing evidence suggests that a broad range of behavioral anomalies in people with autism spectrum disorder (ASD) can be linked with morphological and functional alterations in the brain. However, the neuroanatomical underpinnings of ASD have been investigated using either structural magnetic resonance imaging (MRI) or diffusion tensor imaging (DTI), and the relationships between abnormalities revealed by these two modalities remain unclear. This study applied a multimodal data-fusion method, known as linked independent component analysis (ICA), to a set of structural MRI and DTI data acquired from 46 adult males with ASD and 46 matched controls in order to elucidate associations between different aspects of atypical neuroanatomy of ASD. Linked ICA identified two composite components that showed significant between-group differences, one of which was significantly correlated with age. In the other component, participants with ASD showed decreased gray matter (GM) volumes in multiple regions, including the bilateral fusiform gyri, bilateral orbitofrontal cortices, and bilateral pre- and post-central gyri. These GM changes were linked with a pattern of decreased fractional anisotropy (FA) in several white matter tracts, such as the bilateral inferior longitudinal fasciculi, bilateral inferior fronto-occipital fasciculi, and bilateral corticospinal tracts. Furthermore, unimodal analysis for DTI data revealed significant reductions of FA along with increased mean diffusivity in those tracts for ASD, providing further evidence of disrupted anatomical connectivity. Taken together, our findings suggest that, in ASD, alterations in different aspects of brain morphology may co-occur in specific brain networks, providing a comprehensive view for understanding the neuroanatomy of this disorder.

Pharmacognostic studies on ginger and related drugs—part 1: five sulfonated compounds from Zingiberis rhizome (Shokyo)

Five sulfonated compounds, namely 4-gingesulfonic acid and shogasulfonic acids A, B, C and D, were isolated together with seven known compounds including 6-gingesulfonic acid from Zingiberis rhizome (Japanese name: Shokyo) made out of ginger. Their structures were characterized by means of spectroscopic analysis.

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.

Hot Water Extract of Adzuki (Vigna angularis) Suppresses Antigen-Stimulated Degranulation in Rat Basophilic Leukemia RBL-2H3 Cells and Passive Cutaneous Anaphylaxis Reaction in Mice

The hot water extract of adzuki (HWEA), which is produced as a byproduct in the adzuki bean boiling process, has anti‐tumor, antioxidative, and anti‐diabetic activities. In this study, we fractionated HWEA to 4 fractions using stepwise gradient column chromatography with water and ethanol, and demonstrated the effects of each fraction on antigen (Ag)‐stimulated degranulation in rat basophilic leukemia RBL‐2H3 cells. The 40% ethanol eluate extract (EtEx.40) showed the strongest inhibition level of these fractions. To reveal the inhibitory mechanisms underlying degranulation by EtEx.40, we investigated intracellular reactive oxygen species (ROS) production, intracellular free Ca2+ concentration ([Ca2+]i), and early intracellular signaling pathways. Treatment with EtEx.40 markedly inactivated Lyn following Ag stimulation, resulting in the suppressions of intracellular elevation of [Ca2+]i and production of ROS. To identify the active compound in EtEx.40, we isolated 7 flavonoids from EtEx.40 and calculated their inhibition levels on Ag‐stimulated degranulation. These flavonoids inhibited degranulation by about 25–60%. We further examined the in vivo effects of HWEA or EtEx.40 using a passive cutaneous anaphylaxis (PCA) reaction. Both extracts strongly suppressed the PCA reaction. These findings suggest that HWEA and/or EtEx.40 are beneficial for alleviating type I allergic symptoms. Copyright

Effect of Kampo Herbal Medicines on Murine Water Metabolism in a Microgravity Environment

To determine the possibility of new applications of Oriental medicines, we examined the changes in water metabolism of mice that underwent microgravity and were treated with Kampo medicines. Male ICR mice were used in this experiment. Eight extracts of Kampo herbal medicines were dissolved in water and added to the drinking water administered to mice at 1 g/kg body weight for two days. The microgravity experiment was performed at the Japan Microgravity Center. We used a drop-shaft type microgravity experimental system with a free fall of 490 m. Before the drop, 7 ml of physiological saline was injected intraperitoneally. Under fasting and dehydration, body weights were measured and loss of body weight was calculated as urine. Blood samples were collected 24 hours after the microgravity experiment, and the antidiuretic hormone (ADH) in plasma related to water metabolism was measured by the radioimmunoassay (RIA) method. Heat shock protein in the spleen was measured by the enzyme-linked immunosolvent assay (ELISA) method. In the Hachimi-jio-gan and Hochu-ekki-to groups in microgravity, a decrease of urine was observed, which significantly suppressed the increase of ADH due to microgravity. Hachimi-jio-gan reduced the content of heat shock protein (HSP) 70 in the spleen. It is suggested that Hachimi-jio-gan and Hochu-ekki-to could be used as water metabolism adjustment reagents in a space environment. Furthermore, it is suggested that Hachimi-jio-gan could ease the stresses caused by microgravity. The physiological changes resulting from a microgravity environment are serious problems for space flight. Pre-treatment with Kampo medicines is expected to prevent, ease and treat these problems.