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Dive into the research topics where Asuka Katsuki is active.

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Featured researches published by Asuka Katsuki.


Progress in Neuro-psychopharmacology & Biological Psychiatry | 2010

Adding a low dose atypical antipsychotic drug to an antidepressant induced a rapid increase of plasma brain-derived neurotrophic factor levels in patients with treatment-resistant depression.

Reiji Yoshimura; Atsuko Ikenouchi-Sugita; Hikaru Hori; Wakako Umene-Nakano; Asuka Katsuki; Kenji Hayashi; Nobuhisa Ueda; Jun Nakamura

Only two-thirds of depressive patients respond to antidepressant treatment. Recently, addition of an atypical antipsychotic drug to ongoing treatment with an antidepressant has been considered effective and well-tolerated. In the present study, we examined the effects of various atypical antipsychotic drugs as adjuvant to antidepressants, including selective serotonin reuptake inhibitors (SSRIs), serotonin noradrenaline reuptake inhibitors, tricyclic antidepressants and mood stabilizers, on plasma BDNF levels in refractory depressed patients. Forty-five patients who met the DSM-IV criteria for major depressive disorder (n=31) or bipolar disorder (10 with bipolar I, 4 with bipolar II) were enrolled in the study. Twenty-one were male and 24 were female, and their ages ranged from 28 to 71 (mean+/-SD=49+/-12) years. Plasma BDNF levels were measured using a sandwich ELISA. The plasma BDNF levels in responders (those showing a decline in HAM-D scores of 50% or more) were significantly increased 4weeks after the administration of each atypical antipsychotic drug, while the levels in non-responders were not changed. Furthermore, there was a significant correlation between the changes in HAM-D scores and the changes in plasma BDNF levels. These results suggest that adding an atypical antipsychotic drug to ongoing treatment with an antidepressant or mood stabilizer is useful and well-tolerated for refractory depressed patients, and the efficacy of atypical antipsychotics as an adjuvant might involve an increase of plasma BDNF levels.


Neuropsychiatric Disease and Treatment | 2012

six-month treatment with atypical antipsychotic drugs decreased frontal-lobe levels of glutamate plus glutamine in early-stage first-episode schizophrenia

Naoki Goto; Reiji Yoshimura; Shingo Kakeda; Joji Nishimura; Junji Moriya; Kenji Hayashi; Asuka Katsuki; Hikaru Hori; Wakako Umene-Nakano; Atsuko Ikenouchi-Sugita; Yukunori Korogi; Jun Nakamura

Objective To study the effects of treatment with atypical antipsychotic drugs on brain levels of glutamate plus glutamine in early-stage first-episode schizophrenia. Participants Sixteen patients (eight males, eight females; aged 30 ± 11 years) completed the study. Methods We used administered 6 months of atypical antipsychotic drugs and used proton magnetic resonance spectroscopy to evaluate the results. Results We found that the administration of atypical antipsychotic drugs for 6 months decreased the glutamate plus glutamine/creatine ratio in the frontal lobe. These results suggest that the administration of atypical antipsychotic drugs for at least 6 months decreased glutamatergic neurotransmissions in the frontal lobe in early-stage first-episode schizophrenia, but there was no difference in frontal-lobe levels between patients and control subjects before administration. Conclusion Taking these findings into account, the glutamatergic and GABAergic neurons are implicated in early-stage first-episode schizophrenia, but in complex ways.


Human Psychopharmacology-clinical and Experimental | 2012

Aripiprazole altered plasma levels of brain-derived neurotrophic factor and catecholamine metabolites in first-episode untreated Japanese schizophrenia patients.

Reiji Yoshimura; Hikaru Hori; Atsuko Ikenouchi-Sugita; Wakako Umene-Nakano; Asuka Katsuki; Kenji Hayashi; Kiyokazu Atake; Masaru Tomita; Jun Nakamura

We investigated the effects of aripiprazole on plasma levels of brain‐derived neurotrophic factor (BDNF) and catecholamine metabolites in first‐episode untreated schizophrenia patients.


Psychiatry Research-neuroimaging | 2011

Relationships between stress, social adaptation, personality traits, brain-derived neurotrophic factor and 3-methoxy-4-hydroxyphenylglycol plasma concentrations in employees at a publishing company in Japan

Kanae Okuno; Reiji Yoshimura; Nobuhisa Ueda; Atsuko Ikenouchi-Sugita; Wakako Umene-Nakano; Hikaru Hori; Kenji Hayashi; Asuka Katsuki; Hsin-I Chen; Jun Nakamura

There is growing evidence that blood levels of brain-derived neurotrophic factor (BDNF) and 3-methoxy-4-hydroxyphenylglycol (MHPG), a major metabolite of noradrenaline, are related to depression-associated personality traits as well as to depressive, suicidal and anxious states. Psychological job stress is well known to lead to symptoms of depression, anxiety and suicide. We have recently reported that psychological job stress among hospital employees altered blood levels of BDNF and MHPG (Mitoma et al., 2008). In the present study, we re-examined the effects of social adaptation and personality traits, as well as those of psychological job stress, on plasma levels of BDNF and MHPG in healthy employees (n=269, male/female=210/59, age=49 ± 10years) working in a publishing company in Japan. The values (mean ± SD) of scores on the Stress and Arousal Check Lists (s-SACL and a-SACL), Social Adaptation Self-evaluation Scale (SASS), plasma MHPG levels and plasma BDNF levels were 6.0 ± 3.4, 5.7 ± 2.3, 33.7 ± 6.8, 5.8 ± 4.3 and 4.6 ± 3.1ngml(-1), respectively. A positive correlation was found between plasma MHPG levels and scores on the s-SACL, but not the a-SACL. A positive correlation was also found between SASS scores and plasma MHPG levels and between SASS scores and plasma BDNF levels. A negative correlation was found between plasma BDNF levels and s-SACL scores. Furthermore, a positive correlation between NEO-Five factor Inventory (Openness) scores and plasma MHPG levels was observed, as well as between NEO-Five factor Inventory (Extroversion) scores and plasma BDNF levels. These results suggest that levels of plasma BDNF and plasma MHPG might be associated with psychological job stress and certain personality traits among employees in the publishing industry in Japan.


Cns Spectrums | 2012

Serum levels of brain-derived neurotrophic factor (BDNF), BDNF gene Val66Met polymorphism, or plasma catecholamine metabolites, and response to mirtazapine in Japanese patients with major depressive disorder (MDD)

Asuka Katsuki; Reiji Yoshimura; Taro Kishi; Hikaru Hori; Wakako Umene-Nakano; Atsuko Ikenouchi-Sugita; Kenji Hayashi; Kiyokazu Atake; Nakao Iwata; Jun Nakamura

OBJECT We investigated an association between the polymorphism of brain-derived neurotrophic factor (BDNF) gene Val66Met and the response to mirtazapine in Japanese patients with major depressive disorder (MDD). We also examined mirtazapines effects on the serum BDNF and plasma levels of catecholamine metabolites in these patients. METHODS Eighty-four patients who met the DSM-IV-TR criteria for MDD were treated with only mirtazapine for 4 weeks. The BDNF Val66Met polymorphism was detected by direct sequencing in the region, and serum BDNF levels and plasma levels of catecholamine metabolites were measured by ELISA and HPLC-ECD, respectively. RESULTS Mirtazapine treatment for 4 weeks significantly increased serum BDNF levels in the responders, whereas nonresponders showed significant decreases. No association was found between either of the two genotypes (Val/Val vs. Met-carriers) and the response to mirtazapine at T4 or the serum BDNF levels at T0. Mirtazapine did not alter the plasma levels of homovanillic acid (HVA) or 3-methoxy-4-hydroxyphenylglycol (MHPG). Discussion The dynamics of serum BDNF levels, but not plasma levels of HVA and MHPG, reflect the response to mirtazapine treatment; the BDNF Val66Met polymorphism in patients with depression is, however, associated with neither a particular response to mirtazapine treatment nor baseline serum BDNF levels. CONCLUSION Serum BDNF levels, but not plasma levels of HVA or MHPG, and BDNF Val66Met polymorphism are related to the mirtazapine response in MDD.


Progress in Neuro-psychopharmacology & Biological Psychiatry | 2010

No alterations of brain GABA after 6 months of treatment with atypical antipsychotic drugs in early-stage first-episode schizophrenia

Naoki Goto; Reiji Yoshimura; Shingo Kakeda; Junji Moriya; Hikaru Hori; Kenji Hayashi; Atsuko Ikenouchi-Sugita; Wakako Nakano-Umene; Asuka Katsuki; Joji Nishimura; Yukunori Korogi; Jun Nakamura

We investigated the effects of atypical antipsychotic drugs on GABA concentrations in early-stage, first-episode schizophrenia patients. Sixteen (8 males, 8 females; age, 30±11 years old) patients were followed up for six months. We also included 18 sex- and age-matched healthy control subjects. All patients were treated with atypical antipsychotic drugs (5 patients with risperidone, 5 patients with olanzapine, 4 patients with aripiprazole, and 2 patients with quetiapine). In all three regions measured (frontal lobe, left basal ganglia, and parieto-occipital lobe), no differences in GABA concentrations were observed in a comparison of pre-treatment levels and those six months after treatment. These results suggest that relatively short-term treatment with atypical antipsychotic drugs may not affect GABAergic neurotransmission; however, it is also possible that such treatment prevents further reductions in brain GABA levels in people with early-stage, first-episode schizophrenia.


Human Psychopharmacology-clinical and Experimental | 2010

Plasma levels of brain-derived neurotrophic factor and interleukin-6 in patients with dysthymic disorder: comparison with age- and sex-matched major depressed patients and healthy controls

Reiji Yoshimura; Wakako Umene-Nakano; Tsutomu Hoshuyama; Atsuko Ikenouchi-Sugita; Hikaru Hori; Asuka Katsuki; Kenji Hayashi; Kiyokazu Atake; Jun Nakamura

In the present study, we investigated the serum BDNF levels and plasma IL‐6 levels in patients with dysthymic disorder, major depressive disorder and control subjects. Eighteen patients who met the DSM‐IV criteria (American Psychiatric Association, 1994) for dysthymic disorder (male/female: 5/13; age: 36 ± 9 year) and 20 patients (male/female: 7/13; age: 38 ± 10 year) who met the criteria for major depressive disorder were enrolled. The serum BDNF levels in patients with dysthymic and major depressive disorder were significantly lower than those in the control subjects. However, no difference was found between the dysthymic group and major depression group. The plasma IL‐6 levels in the dysthymic group and major depression group were significantly higher than those in the control group. No difference was observed in the plasma IL‐6 levels between the dysthymic group and major depression group. These results suggest that the pathophysiology of dysthymic disorder and major depression might be similar in terms of the blood levels of BDNF and IL‐6. Copyright


Journal of Psychiatric Research | 2012

The cognitive profile of aripiprazole differs from that of other atypical antipsychotics in schizophrenia patients.

Hikaru Hori; Reiji Yoshimura; Asuka Katsuki; Kenji Hayashi; Atsuko Ikenouchi-Sugita; Wakako Umene-Nakano; Jun Nakamura

We investigated the effects of the atypical antipsychotics risperidone, olanzapine, and aripiprazole on the cognitive functions of Japanese patients with schizophrenia with respect to dosage amounts and dosing schedules. We performed a cross-sectional survey using the Brief Assessment of Cognition in Schizophrenia - Japanese Language Version (BACS-J) to evaluate the neurocognitive functions of 101 schizophrenic patients who took the same dose of one of the three aforementioned antipsychotics for at least 3 months. The BACS-J composite score correlated negatively with the prescribed dosages of risperidone and olanzapine. In contrast, we did not find a correlation between the BACS-J composite score and the prescribed dosage of aripiprazole. Moreover, the primary scores for verbal learning, motor function, and attention and processing speed were significantly lower among the patients who were taking the prescribed dosage of risperidone. The scores for verbal learning and motor function were also significantly lower when correlated with the prescribed dosage of olanzapine. We did not find a correlation between any of the primary scores on the BACS-J and the prescribed dosage of aripiprazole. In fact, the results suggest there is no linear relationship between the dose of aripiprazole and cognitive impairment, which may be due to its unique pharmacological profile.


PLOS ONE | 2014

Abnormal White Matter Integrity in the Corpus Callosum among Smokers: Tract-Based Spatial Statistics

Wakako Umene-Nakano; Reiji Yoshimura; Shingo Kakeda; Keita Watanabe; Kenji Hayashi; Joji Nishimura; Hidehiko Takahashi; Junji Moriya; Satoru Ide; Issei Ueda; Hikaru Hori; Atsuko Ikenouchi-Sugita; Asuka Katsuki; Kiyokazu Atake; Osamu Abe; Yukunori Korogi; Jun Nakamura

In the present study, we aimed to investigate the difference in white matter between smokers and nonsmokers. In addition, we examined relationships between white matter integrity and nicotine dependence parameters in smoking subjects. Nineteen male smokers were enrolled in this study. Eighteen age-matched non-smokers with no current or past psychiatric history were included as controls. Diffusion tensor imaging scans were performed, and the analysis was conducted using a tract-based special statistics approach. Compared with nonsmokers, smokers exhibited a significant decrease in fractional anisotropy (FA) throughout the whole corpus callosum. There were no significant differences in radial diffusivity or axial diffusivity between the two groups. There was a significant negative correlation between FA in the whole corpus callosum and the amount of tobacco use (cigarettes/day; R = − 0.580, p = 0.023). These results suggest that the corpus callosum may be one of the key areas influenced by chronic smoking.


Human Psychopharmacology-clinical and Experimental | 2013

Plasma levels of interleukin-6 and selective serotonin reuptake inhibitor response in patients with major depressive disorder

Reiji Yoshimura; Hikaru Hori; Atsuko Ikenouchi-Sugita; Wakako Umene-Nakano; Asuka Katsuki; Kiyokazu Atake; Jun Nakamura

We investigated the plasma levels of interleukin (IL)‐6 and 5‐HTT polymorphisms in patients with major depressive disorder (MDD). This is the first report, to our knowledge, of an investigation into the association between 5‐HTT gene polymorphism, plasma IL‐6 levels, and responses to selective serotonin reuptake inhibitors (SSRIs) in Japanese patients with MDD.

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Reiji Yoshimura

University of Occupational and Environmental Health Japan

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Hikaru Hori

University of Occupational and Environmental Health Japan

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Jun Nakamura

University of Occupational and Environmental Health Japan

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Wakako Umene-Nakano

University of Occupational and Environmental Health Japan

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Kiyokazu Atake

University of Occupational and Environmental Health Japan

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Atsuko Ikenouchi-Sugita

University of Occupational and Environmental Health Japan

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Kenji Hayashi

University of Occupational and Environmental Health Japan

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Shingo Kakeda

University of Occupational and Environmental Health Japan

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Yukunori Korogi

University of Occupational and Environmental Health Japan

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Nakao Iwata

Fujita Health University

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