Toshiro Harada

Kagoshima University, Kagosima, Kagoshima, Japan

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Publications (7)41.16 Total impact

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    ABSTRACT: Subjects with restrictive anorexia nervosa (AN) display increased basal plasma levels of ghrelin that normalize after refeeding. The mechanism responsible for increased ghrelin levels in AN is unknown. We studied if changes of ghrelin reactive autoantibodies (autoAbs) could explain elevated plasma ghrelin in AN. Plasma levels of autoAbs reactive with ghrelin and des-acyl ghrelin were measured by enzyme-linked immunosorbent assay in subjects with AN before and 1 mo after hospitalization (refeeding) and compared with healthy controls and with plasma levels of ghrelin peptides. Decreased levels of immunoglobulin (Ig) G, IgM, and IgA classes of autoAbs reacting with acyl ghrelin were found in patients with AN. Addition of des-acyl ghrelin but not of acyl ghrelin peptides at 10(-8) M to plasma before enzyme-linked immunosorbent assay showed in patients with AN but not in controls high levels of IgG autoAbs reacting with des-acyl ghrelin as a result of dissociation of des-acyl ghrelin autoAbs in immune complexes. Plasma levels of acyl and des-acyl ghrelin peptides correlated negatively with des-acyl ghrelin IgG autoAbs. Body mass index, which improved after refeeding, correlated with an increase of acyl ghrelin IgM autoAbs. These results show that in patients with AN, ghrelin IgG autoAbs exist mainly as immune complexes with des-acyl ghrelin accompanied by a decrease of a free fraction of these autoAbs binding acylated and des-acyl ghrelin. This decrease of bioavailable ghrelin autoAbs may underlie a long-term elevation of plasma ghrelin levels and the resulting phenomenon of ghrelin resistance in malnourished patients with AN.
    Nutrition 04/2011; 27(4):407-13. · 3.05 Impact Factor
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    ABSTRACT: Restricting-type anorexia nervosa (AN-R) is characterized by chronic food restriction and severe emaciation due to various cognitive biases such as a distorted self-image. In spite of several treatments, AN-R continues to be a refractory disease because of its unknown pathogenesis. Although previous studies have shown that changes in feeding regulatory peptides such as ghrelin are involved in anorexia, few reports have described the relationship between AN-R and nesfatin-1, a recently identified satiety peptide. Therefore, we examined the plasma nesfatin-1 levels in AN-R patients to determine its role in AN-R. A total of 15 women participated in the study; 7 patients with AN-R and 8 age-matched healthy controls (average BMI, 13.02 ± 0.30 vs. 21.57 ± 0.48, respectively). Our results showed that plasma nesfatin-1 levels were significantly lower in AN-R group than in control group (6.23 ± 0.70 ng/ml vs. 8.91 ± 0.85 ng/ml, respectively, P<0.05). Plasma acyl ghrelin and des-acyl ghrelin levels were significantly higher in AN-R group than in control group (acyl ghrelin: 62.4 ± 10.15 fmol/ml vs. 27.20 ± 5.60 fmol/ml, P<0.01 and des-acyl ghrelin: 300.17 ± 55.95 fmol/ml vs. 107.34 ± 40.63 fmol/ml, P<0.05). Although AN-R is associated with emaciation for a prolonged period, our result suggested that nesfatin-1 levels may be regulated by nutrition status and response to starvation.
    Peptides 10/2010; 32(1):150-3. · 2.61 Impact Factor
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    ABSTRACT: Obestatin is a recently identified ghrelin gene product that was reported to inhibit appetite and gastric motility in contrast to ghrelin. We investigated fasting obestatin and ghrelin levels in patients with obesity and anorexia nervosa. Fasting plasma obestatin, acyl-ghrelin, desacyl-ghrelin, leptin, glucose serum adiponectin, and insulin were measured in 10 obese subjects, 11 restricting-type anorexics, and 11 control subjects. Obese group had significantly lower levels of obestatin (p < .01), while anorexic group had significantly higher levels (p < .01). Obestatin was negatively correlated with body mass index (BMI) (r = -.74), glucose (r = -.56), insulin (r = -.55), leptin (r = -.66), and also with the homeostasis model assessment of insulin resistance (HOMA-R) (r = -.49) and was positively correlated with acyl-ghrelin (r = .65) and desacyl-ghrelin (r = .60). No correlation was seen between obestatin and adiponectin, but the latter was negatively correlated with both acyl-ghrelin and desacyl-ghrelin. Desacyl-ghrelin to acyl-ghrelin ratio was significantly different between anorexic and control groups (p < .05), while no difference was seen between obese and control groups. Both obestatin and ghrelin are increased in anorexic and decreased in obesity. We suggest that obestatin is a nutritional marker reflecting body adiposity and insulin resistance.
    Biological psychiatry 08/2008; 64(3):252-5. · 8.93 Impact Factor
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    ABSTRACT: Obestatin is a recently identified peptide encoded by the same ghrelin gene. It has been reported that obestatin has anorexigenic and antigastroprokinetic activities as opposed to ghrelin. We investigated simultaneously obestatin, acyl ghrelin, and des-acyl ghrelin in the restricting type of anorexia nervosa (AN-R) patients. Three hormonal responses to the oral glucose tolerance test (OGTT) were measured in 10 AN-R patients and 10 healthy women. Plasma obestatin, acyl ghrelin, and des-acyl ghrelin levels were significantly higher in AN-R patients than in control subjects throughout the OGTT. All of the three hormones decreased after the OGTT in both groups. We found that AN-R patients exhibited increased plasma levels of obestatin, acyl ghrelin, and des-acyl ghrelin throughout the OGTT compared with control subjects. The hormonal differences between groups are statistically most significant in obestatin, suggesting obestatin may serve as a marker reflecting both acute and chronic changes of the nutritional state in AN-R patients.
    Biological psychiatry 02/2008; 63(2):245-7. · 8.93 Impact Factor
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    ABSTRACT: In humans, ghrelin has been found to stimulate appetite while PYY3-36 to reduce it; these orexigenic and anorexigenic peptides play significant roles in appetite control. We investigated pre- and postprandial responses of ghrelin and PYY in anorexia nervosa (AN) and the influence of weight gain. Plasma ghrelin, PYY3-36, glucose and insulin responses after ingestion of a 400 kcal standard meal were measured in 14 patients with restricting type of AN and 12 controls. The AN patients were evaluated before therapy and after inpatient therapy. Psychometry was performed by the use of Eating Disorders Inventory. Ghrelin was suppressed during the meal test, while PYY3-36 was increased in all of the groups. Before therapy, AN patients had significantly increased levels of ghrelin and PYY3-36 compared to the control (P<0.01). After therapeutic intervention, as the nutritional status of AN patients improved, the secretion of these hormones were increased (P<0.05), but not normalized as in psychological testing. In contrast, insulin and glucose responses were normalized after inpatient therapy. We found that both ghrelin and PYY3-36 increased in AN patients and these changes were not normalized in contrast to insulin after treatment. The increase in both orexigenic ghrelin and anorexigenic PYY3-36 may have a role in pathological eating behavior in AN.
    Journal of Psychiatric Research 12/2007; 41(10):814-20. · 4.09 Impact Factor
  • American Journal of Psychiatry 04/2007; 164(3):528-9. · 13.56 Impact Factor
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    ABSTRACT: The aim of this study was to investigate the effect of juggling therapy for anxiety disorder patients. Subjects were 17 female outpatients who met the DSM-IV diagnostic criteria for anxiety disorders. Subjects were treated with standard psychotherapy, medication and counseling for 6 months. For the last 3 months of treatment, subjects were randomized into either a non-juggling group (n = 9) or a juggling therapy group (juggling group: n = 8). The juggling group gradually acquired juggling skills by practicing juggling beanbags (otedama in Japan) with both hands. The therapeutic effect was evaluated using scores of psychological testing (STAI: State and Trate Anxiety Inventry, POMS: Profile of Mood Status) and of ADL (FAI: Franchay Activity Index) collected before treatment, 3 months after treatment (before juggling therapy), and at the end of both treatments. After 6 months, an analysis of variance revealed that scores on the state anxiety, trait anxiety subscales of STAI and tension-anxiety (T-A) score of POMS were significantly lower in the juggling group than in the non-juggling group (p < 0.01). Depression, anger-hostility scores of POMS were improved more than non-jugglers. In the juggling group, activity scores on the vigor subscale of POMS and FAI score were significantly higher than those in the non juggling group (p < 0.01). Other mood scores of POMS did not differ between the two groups. These findings suggest that juggling therapy may be effective for the treatment of anxiety disorders.
    BioPsychoSocial Medicine 02/2007; 1:10.