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Dive into the research topics where Akihiro Shiina is active.

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Featured researches published by Akihiro Shiina.


PLOS ONE | 2012

Decreased Serum Levels of Mature Brain-Derived Neurotrophic Factor (BDNF), but Not Its Precursor proBDNF, in Patients with Major Depressive Disorder

Taisuke Yoshida; Masatomo Ishikawa; Tomihisa Niitsu; Michiko Nakazato; Hiroyuki Watanabe; Tetsuya Shiraishi; Akihiro Shiina; Tasuku Hashimoto; Nobuhisa Kanahara; Tadashi Hasegawa; Masayo Enohara; Atsushi Kimura; Masaomi Iyo; Kenji Hashimoto

Background Meta-analyses have identified serum levels of brain-derived neurotrophic factor (BDNF) as a potential biomarker for major depressive disorder (MDD). However, at the time, commercially available human ELISA kits are unable to distinguish between proBDNF (precursor of BDNF) and mature BDNF because of limited BDNF antibody specificity. In this study, we examined whether serum levels of proBDNF, mature BDNF, and matrix metalloproteinase-9 (MMP-9), which converts proBDNF to mature BDNF, are altered in patients with MDD. Methodology/Principal Findings Sixty-nine patients with MDD and 78 age- and gender-matched healthy subjects were enrolled. Patients were evaluated using 17 items on the Structured Interview Guide for the Hamilton Depression Rating Scale. Cognitive impairment was evaluated using the CogState battery. Serum levels of proBDNF, mature BDNF, and MMP-9 were measured using ELISA kits. Serum levels of mature BDNF in patients with MDD were significantly lower than those of normal controls. In contrast, there was no difference in the serum levels of proBDNF and MMP-9 between patients and normal controls. While neither proBDNF nor mature BDNF serum levels was associated with clinical variables, there were significant correlations between MMP-9 serum levels and the severity of depression, quality of life scores, and social function scores in patients. Conclusions/Significance These findings suggest that mature BDNF may serve as a biomarker for MDD, and that MMP-9 may play a role in the pathophysiology of MDD. Further studies using larger sample sizes will be needed to investigate these results.


Annals of General Psychiatry | 2010

A randomised, double-blind, placebo-controlled trial of tropisetron in patients with schizophrenia

Akihiro Shiina; Yukihiko Shirayama; Tomihisa Niitsu; Tasuku Hashimoto; Taisuke Yoshida; Tadashi Hasegawa; Tadashi Haraguchi; Nobuhisa Kanahara; Tetsuya Shiraishi; Mihisa Fujisaki; Goro Fukami; Michiko Nakazato; Masaomi Iyo; Kenji Hashimoto

BackgroundCognitive deficits in schizophrenia are associated with psychosocial deficits that are primarily responsible for the poor long-term outcome of this disease. Auditory sensory gating P50 deficits are correlated with neuropsychological deficits in attention, one of the principal cognitive disturbances in schizophrenia. Our studies suggest that the α7 nicotinic acetylcholine receptor (α7 nAChR) agonist tropisetron might be a potential therapeutic drug for cognitive deficits in schizophrenia. Therefore, it is of particular interest to investigate the effects of tropisetron on the cognitive deficits in patients with schizophrenia.MethodsA randomised, placebo-controlled trial of tropisetron in patients with schizophrenia was performed. A total of 40 patients with chronic schizophrenia who had taken risperidone (2 to 6 mg/day) were enrolled. Subjects were randomly assigned to a fixed titration of tropisetron (n = 20, 10 mg/day) or placebo (n = 20) in an 8-week double-blind trial. Auditory sensory gating P50 deficits and Quality of Life Scale (QLS), Cambridge Neuropsychological Test Automated Battery (CANTAB), and Positive and Negative Syndrome Scale (PANSS) scores were measured.ResultsIn all, 33 patients completed the trial. Tropisetron was well tolerated. Administration of tropisetron, but not placebo, significantly improved auditory sensory gating P50 deficits in non-smoking patients with schizophrenia. The score on the rapid visual information processing (sustained visual attention) task of CANTAB was significantly improved by tropisetron treatment. Total and subscale scores of PANSS were not changed by this trial. QLS scores in the all patients, but not non-smoking patients, were significantly improved by tropisetron trial.ConclusionsThis first randomised, double-blind, placebo-controlled trial supports the safety and efficacy of adjunctive tropisetron for treatment of cognitive deficits in schizophrenia.


Brain | 2012

Subthalamic deep brain stimulation can improve gastric emptying in Parkinson's disease

Eiji Arai; Makoto Arai; Tomoyuki Uchiyama; Yoshinori Higuchi; Kyoko Aoyagi; Yoshitaka Yamanaka; Tatsuya Yamamoto; Osamu Nagano; Akihiro Shiina; Daisuke Maruoka; Tomoaki Matsumura; Tomoo Nakagawa; Tatsuro Katsuno; Fumio Imazeki; Naokatsu Saeki; Satoshi Kuwabara; Osamu Yokosuka

It is established that deep brain stimulation of the subthalamic nucleus improves motor function in advanced Parkinsons disease, but its effects on autonomic function remain to be elucidated. The present study was undertaken to investigate the effects of subthalamic deep brain stimulation on gastric emptying. A total of 16 patients with Parkinsons disease who underwent bilateral subthalamic deep brain stimulation were enrolled. Gastric emptying was expressed as the peak time of (13)CO(2) excretion (T(max)) in the (13)C-acetate breath test and was assessed in patients with and without administration of 100-150 mg levodopa/decarboxylase inhibitor before surgery, and with and without subthalamic deep brain stimulation at 3 months post-surgery. The pattern of (13)CO(2) excretion curve was analysed. To evaluate potential factors related to the effect of subthalamic deep brain stimulation on gastric emptying, we also examined the association between gastric emptying, clinical characteristics, the equivalent dose of levodopa and serum ghrelin levels. The peak time of (13)CO(2) excretion (T(max)) values for gastric emptying in patients without and with levodopa/decarboxylase inhibitor treatment were 45.6 ± 22.7 min and 42.5 ± 13.6 min, respectively (P = not significant), thus demonstrating levodopa resistance. The peak time of (13)CO(2) excretion (T(max)) values without and with subthalamic deep brain stimulation after surgery were 44.0 ± 17.5 min and 30.0 ± 12.5 min (P < 0.001), respectively, which showed that subthalamic deep brain stimulation was effective. Simultaneously, the pattern of the (13)CO(2) excretion curve was also significantly improved relative to surgery with no stimulation (P = 0.002), although the difference with and without levodopa/decarboxylase inhibitor was not significant. The difference in peak time of (13)CO(2) excretion (T(max)) values without levodopa/decarboxylase inhibitor before surgery and without levodopa/decarboxylase inhibitor and subthalamic deep brain stimulation after surgery was not significant, although motor dysfunction improved and the levodopa equivalent dose decreased after surgery. There was little association between changes in ghrelin levels (Δghrelin) and changes in T(max) values (ΔT(max)) in the subthalamic deep brain stimulation trial after surgery (r = -0.20), and no association between changes in other characteristics and ΔT(max) post-surgery in the subthalamic deep brain stimulation trial. These results showed that levodopa/decarboxylase inhibitor did not influence gastric emptying and that subthalamic deep brain stimulation can improve the dysfunction in patients with Parkinsons disease possibly by altering the neural system that controls gastrointestinal function after subthalamic deep brain stimulation. This is the first report to show the effectiveness of subthalamic deep brain stimulation on gastrointestinal dysfunction as a non-motor symptom in Parkinsons disease.


Progress in Neuro-psychopharmacology & Biological Psychiatry | 2011

Associations of serum brain-derived neurotrophic factor with cognitive impairments and negative symptoms in schizophrenia

Tomihisa Niitsu; Yukihiko Shirayama; Daisuke Matsuzawa; Tadashi Hasegawa; Nobuhisa Kanahara; Tasuku Hashimoto; Tetsuya Shiraishi; Akihiro Shiina; Goro Fukami; Mihisa Fujisaki; Hiroyuki Watanabe; Michiko Nakazato; Makoto Asano; Sho Kimura; Kenji Hashimoto; Masaomi Iyo

Brain-derived neurotrophic factor (BDNF) may be involved in the pathophysiology of schizophrenia. The aim of this study was to examine the associations of serum BDNF levels with the cognition and clinical characteristics in patients with schizophrenia. Sixty-three patients with schizophrenia and 52 age- and sex-matched healthy controls were examined with neuropsychological tests. Serum BDNF levels were determined by enzyme-linked immunosorbent assay (ELISA). There were no significant differences in serum BDNF levels between normal controls and patients with schizophrenia. Serum BDNF levels of normal controls showed negative correlations with verbal working memory, but this was not the case with schizophrenic patients. Meanwhile, serum BDNF levels of schizophrenic patients showed positive correlations with the scores of the Scale for the Assessment of Negative Symptoms (SANS) and the Information subtest scores of Wechsler Adult Intelligence Scale Revised (WAIS-R). Serum BDNF levels are related with the impairment of verbal working memory and negative symptoms in patients with schizophrenia.


Progress in Neuro-psychopharmacology & Biological Psychiatry | 2004

No changes in serum ghrelin levels in female patients with bulimia nervosa

Michiko Nakazato; Kenji Hashimoto; Akihiro Shiina; Hiroki Koizumi; Makoto Mitsumoti; Masao Imai; Eiji Shimizu; Masaomi Iyo

It has been reported that fasting plasma ghrelin levels may play a role in the pathophysiology of eating disorders. In this study, the authors examined whether serum levels of ghrelin were altered in the patients with bulimia nervosa (BN). We enrolled 18 female patients with BN, and 21 age-matched female controls for this study. Eating-related psychopathology, depressive symptoms were evaluated by using the Bulimic Investigatory Test, Edinburgh (BITE) and the 17-item Hamilton Depression Rating Scale (HDRS). Serum levels of ghrelin were measured by Ghrelin enzyme immunoassay kit. There were no significant differences in serum ghrelin levels between the patients with BN and normal controls. Furthermore, the authors did not found correlation between serum ghrelin levels and clinical parameters in the patients with BN. Our study suggests that serum ghrelin levels in the patients with BN were indistinguishable from normal controls. Therefore, it is unlikely that ghrelin plays a role in the pathophysiology of BN.


Progress in Neuro-psychopharmacology & Biological Psychiatry | 2008

Fluvoxamine as a sigma-1 receptor agonist improved cognitive impairments in a patient with schizophrenia.

Masaomi Iyo; Yukihiko Shirayama; Hiroyuki Watanabe; Mihisa Fujisaki; Ryosuke Miyatake; Goro Fukami; Akihiro Shiina; Michiko Nakazato; Tetsuya Shiraishi; Tsuyoshi Ookami; Kenji Hashimoto

Patients with schizophrenia exhibit positive and negative symptoms, and these symptoms have been targets for the development of new antipsychotics. In recent years, cognitive impairments in these patients, which may persist across cycles in other aspects of the illness and may be strongly related to the functional outcome, have drawn considerable attention (Hughes et al., 2003; Harvey et al., 2001). It has been reported that the patients themselves are aware of and experience distress due to their cognitive impairments (Ginsberg et al., 2005). Some of the new atypical antipsychotics can improve the impairments, but such amelioration generally remains unsatisfying, and the development of more effective drugs is still necessary (Lehman et al., 1995). Recently, we reported on the efficacy of fluvoxamine, a potent sigma-1 receptor agonist, in improving cognitive impairments in an animal model of schizophrenia (Hashimoto et al., 2007). In the present report, cognitive impairments in a female patient with schizophrenia were dramatically improved by adjunctive treatment of fluvoxamine added to risperidone.


Clinical psychopharmacology and neuroscience : the official scientific journal of the Korean College of Neuropsychopharmacology | 2015

An Open Study of Sulforaphane-rich Broccoli Sprout Extract in Patients with Schizophrenia

Akihiro Shiina; Nobuhisa Kanahara; Tsuyoshi Sasaki; Yasunori Oda; Tasuku Hashimoto; Tadashi Hasegawa; Taisuke Yoshida; Masaomi Iyo; Kenji Hashimoto

Objective Schizophrenia is a mental disorder characterized by severe cognitive impairment. Accumulating evidence suggests a role for oxidative stress in the pathophysiology of schizophrenia. Sulforaphane (SFN) extracted from broccoli sprout is an agent with potent anti-oxidant and anti-inflammatory activity. In this study, we attempted to evaluate the effect of SFN on cognitive impairment in medicated patients with schizophrenia. Methods We recruited a total of 10 outpatients with schizophrenia, all of whom gave informed consent. Participants took 3 tablets of SFN, consisting of 30 mg of SFN-glucosinolate per day, for 8 weeks. Clinical symptoms using the Positive and Negative Syndrome Scale (PANSS) and cognitive function using the Japanese version of CogState battery were evaluated at the beginning of the study and at week 8. Results A total of 7 patients completed the trial. The mean score in the Accuracy component of the One Card Learning Task increased significantly after the trial. However, we detected no other significant changes in participants. Conclusion This result suggests that SFN has the potential to improve cognitive function in patients with schizophrenia.


Journal of Clinical Psychopharmacology | 2012

A randomized, double-blind, placebo-controlled trial of fluvoxamine in patients with schizophrenia: a preliminary study.

Tomihisa Niitsu; Mihisa Fujisaki; Akihiro Shiina; Taisuke Yoshida; Tadashi Hasegawa; Nobuhisa Kanahara; Tasuku Hashimoto; Tetsuya Shiraishi; Goro Fukami; Michiko Nakazato; Yukihiko Shirayama; Kenji Hashimoto; Masaomi Iyo

Abstract Cognitive impairments in schizophrenia are associated with suboptimal psychosocial performance. Several lines of evidence have suggested that endoplasmic reticulum protein sigma-1 receptors were involved in cognitive impairments in patients with schizophrenia and that the sigma-1 receptor agonist fluvoxamine was effective in treating cognitive impairments in animal models of schizophrenia and in some patients with schizophrenia. A randomized, double-blind, placebo-controlled, parallel trial of fluvoxamine adjunctive therapy in patients with schizophrenia was performed. A total of 48 patients with chronic schizophrenia were enrolled. Subjects were randomly assigned to an 8-week administration of add-on fluvoxamine (n = 24, titrated up to 150 mg/d) or placebo (n =24) in a total 12-week double-blind trial. The primary outcome measure was the Cambridge Neuropsychological Test Automated Battery (CANTAB), assessing visual memory, working memory, attention, and executive function. The secondary outcome measures were the Positive and Negative Syndrome Scale, the Scale for the Assessment of Negative Symptoms, the Quality of Life Scale, and the Montgomery-Åsberg Depression Rating Scale. Fluvoxamine was well tolerated. No significant time × group interaction effects were observed in the scores of the CANTAB, Positive and Negative Syndrome Scale, Scale for the Assessment of Negative Symptoms, Quality of Life Scale, or the Montgomery-Åsberg Depression Rating Scale. However, in secondary analyses, the change from baseline to end point on the Spatial Working Memory strategy score (executive function) of CANTAB improved in the fluvoxamine group. This study suggests no major benefit of fluvoxamine adjunctive therapy to improve cognitive impairments in patients with schizophrenia. Nevertheless, a further study using a large sample size will be needed to confirm the secondary analyses findings.


Schizophrenia Research | 2014

A prospective comparative study of risperidone long-acting injectable for treatment-resistant schizophrenia with dopamine supersensitivity psychosis

Hiroshi Kimura; Nobuhisa Kanahara; Naoya Komatsu; Minoru Ishige; Katsumasa Muneoka; Masayuki Yoshimura; Hiroshi Yamanaka; Tomotaka Suzuki; Hideki Komatsu; Tsuyoshi Sasaki; Tasuku Hashimoto; Tadashi Hasegawa; Akihiro Shiina; Masatomo Ishikawa; Yoshimoto Sekine; Tetsuya Shiraishi; Hiroyuki Watanabe; Eiji Shimizu; Kenji Hashimoto; Masaomi Iyo

OBJECTIVE Dopamine supersensitivity psychosis (DSP) is considered to be one cause of treatment-resistant schizophrenia (TRS). The authors investigated the efficacy of risperidone long-acting injections (RLAI) in patients with TRS and DSP. METHOD This is a multicenter, prospective, 12-month follow-up, observational study that included unstable and severe TRS patients with and without DSP. 115 patients with TRS were recruited and divided into two groups according to the presence or absence of DSP which was judged on the basis of the clinical courses and neurological examinations. RLAI was administered adjunctively once every 2weeks along with oral antipsychotics. We observed changes in scores for the Brief Psychiatric Rating Scales (BPRS), Clinical Global Impression-Severity of Illness (CGI-S), Global Assessment of Functioning Scale (GAF), and Extrapyramidal Symptom Rating Scale (ESRS) during the study. Of the assessed 94 patients, 61 and 33 were categorized into the DSP and NonDSP groups, respectively. RESULTS While baseline BPRS total scores, CGI-S scores and GAF scores did not differ, the ESRS score was significantly higher in the DSP group compared with the NonDSP group. Treatment significantly reduced BPRS total scores and CGI-S scores, and increased GAF scores in both groups, but the magnitudes of change were significantly greater in the DSP group relative to the NonDSP group. ESRS scores were also reduced in the DSP group. Responder rates (≥20% reduction in BPRS total score) were 62.3% in the DSP group and 21.2% in the NonDSP group. CONCLUSIONS It is suggested that DSP contributes to the etiology of TRS. Atypical antipsychotic drugs in long-acting forms, such as RLAI, can provide beneficial effects for patients with DSP. CLINICAL TRIALS REGISTRATION UMIN (UMIN000008487).


Psychiatry Research-neuroimaging | 2015

Decreased levels of serum oxytocin in pediatric patients with Attention Deficit/Hyperactivity Disorder

Tsuyoshi Sasaki; Kenji Hashimoto; Yasunori Oda; Tamaki Ishima; Tsutomu Kurata; Junpei Takahashi; Yu Kamata; Hiroshi Kimura; Tomihisa Niitsu; Hideki Komatsu; Masatomo Ishikawa; Tadashi Hasegawa; Akihiro Shiina; Tasuku Hashimoto; Nobuhisa Kanahara; Tetsuya Shiraishi; Masaomi Iyo

Attention Deficit/Hyperactivity Disorder (ADHD) and autism spectrum disorder (ASD) are highly comorbid, and both disorders share executive function deficits. Accumulating evidence suggests that ASD patients have significantly lower peripheral oxytocin (OXT) levels compared with their normal counterparts, and that the repetitive behavior seen in ASD is related to abnormalities in the OXT system. In this study, we investigated whether serum levels of OXT are altered in pediatric patients with ADHD. We measured serum OXT levels: drug naive ADHD (n=23), medicated ADHD (n=13), and age- and sex- matched, neurotypical controls (n=22). Patients were evaluated using the ADHD-RS. Serum levels of OXT in total subjects with ADHD were significantly decreased compared with those of neurotypical controls, and serum levels of OXT in drug naive ADHD patients were significantly lower than those in medicated ADHD patients. Interestingly, there was a significant negative correlation between serum OXT levels and ADHD-RS total scores, as well as ADHD-RS inattentive scores in all ADHD patients. In conclusion, this study suggests that decreased levels of OXT may play a role in the pathophysiology of patients with ADHD and its inherent inattentiveness.

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Kenji Hashimoto

National Institutes of Health

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