Characteristics of Early-Onset Dementia in Chiba Prefecture, Japan: A Multicenter Survey.

INTRODUCTION: Early-onset dementia (EOD), defined as dementia onset before the age of 65 years, is relatively rare, but its social impacts are significant. This study aimed to characterize the diagnosis and clinical and social status of EOD subjects in the 11 dementia centers in Chiba Prefecture, Japan. METHODS: A retrospective 1-year survey was conducted. Collected data included clinical diagnosis, age at onset, age at survey, neuropsychological test, family history, employment, and living status. RESULTS: We identified 208 EOD subjects, including 123 (59.4%), 24 (11.6%), 21 (10.1%), 17 (8.2%), and 10 (4.8%) with Alzheimer's disease (AD), vascular dementia, frontotemporal lobar degeneration (FTLD), dementia with Lewy bodies/Parkinson's disease dementia, and alcohol-related dementia, respectively. The Mini-Mental State Examination (MMSE) score <24 was observed in 50-75% of patients and was not correlated with disease duration. Twenty-four (16.4%) subjects had positive family history of EOD. EOD subjects were at risk of early retirement, and 133 subjects lived with their family, in whom 64 (30.8%) lived with their child. CONCLUSION: In dementia centers, AD, FTLD, and Lewy body dementia had relatively large proportion. Employment, economy, and social supports are urgently needed for EOD subjects and their family.

The effectiveness of very slow switching to aripiprazole in schizophrenia patients with dopamine supersensitivity psychosis: a case series from an open study.

Dopamine supersensitivity psychosis (DSP) in patients with schizophrenia is induced by treatment with a high dosage of antipsychotics for a long time period, and it is characterized by unstable psychotic symptoms. The upregulation of dopamine D2 receptor (DRD2) provoked by antipsychotics underlies DSP. Aripiprazole does not cause an excessive blockade of DRD2 and is less likely to upregulate DRD2 by aripiprazole's dopamine partial agonistic profile. Aripiprazole; however, has a potential risk of inducing severe rebound psychosis in patients who have already developed dopamine supersensitivity. Recently, an animal model study suggested that aripiprazole could attenuate established dopamine supersensitivity. The present study was conducted to examine whether very slowly switching to aripiprazole could help patients with schizophrenia with dopamine supersensitivity while avoiding rebound psychosis. This study was a single-armed and open-labeled study in which patients were observed over a period of 2 years. Only 11 patients were ultimately recruited. Five patients were successfully switched to a sufficient dose of aripiprazole and completed the study protocol. These five patients did not present with severe DSP over the study period, but only one patient showed a large improvement in psychopathology. Five patients dropped out of the study, and one of these five showed a severe worsening of psychosis. The present study indicated that the introduction of aripiprazole in patients with DSP was difficult, but suggested that aripiprazole could contribute to attaining a stable state in psychosis if it was applied with careful observation.

Risperidone long-acting injectable in the treatment of treatment-resistant schizophrenia with dopamine supersensitivity psychosis: Results of a 2-year prospective study, including an additional 1-year follow-up.

UNLABELLED: Dopamine supersensitivity psychosis (DSP) resulting from antipsychotic treatment is related to treatment-resistant schizophrenia (TRS), and its treatment has not been established to date. Maintaining thoroughly stable occupancy of the dopamine D2 receptor by risperidone long-acting injectable (RLAI) is one strategy for treatment. In this study, RLAI was given as an adjunctive medication to oral antipsychotic(s), which were switched partially and gradually to RLAI in 108 treatment-resistant patients for an additional 1-year follow-up in a 2-year study, and to compare the effects in 72 patients with a DSP history (DSP group) and 36 patients without this history (NonDSP group). Although both groups showed significant improvements in the total Brief Psychotic Rating Scale (BPRS) score during the follow-up period, greater improvement was observed for the DSP group than the NonDSP group. High doses (> 850 mg chlorpromazine-dose combined of oral antipsychotics and RLAI) did not significantly change in both groups throughout the study period; however, extrapyramidal symptoms, including tardive dyskinesia, were significantly improved only in the patients with DSP. This study strongly suggested that the RLAI treatment, even with only partial switching, provides relief from refractory symptoms, particularly for patients with a history of DSP. CLINICAL TRIAL REGISTRATION: http://www.umin.ac.jp/:UMIN000008487.

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

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).

Posterior cingulate gyrus metabolic changes in chronic schizophrenia with generalized cognitive deficits.

N-Methyl-d-aspartate (NMDA) receptor antagonists are known to induce schizophrenia-like psychotic symptoms and cognitive deficits in humans, and have been shown to cause neuronal damage in the posterior cingulate gyrus (PCG) of rodents. Patients with chronic schizophrenia exhibit generalized cognitive deficits, but it remains unclear whether or not the PCG is related to their cognitive dysfunction. To determine what biochemical changes may occur in the PCG of patients with chronic schizophrenia, and to ascertain whether or not such abnormalities may be related to the incidence of cognitive deficits, we obtained cognitive scores and proton magnetic resonance spectra (MRS) from the PCG and the left and right medial temporal lobes (MTL) of 19 patients with schizophrenia and 18 age- and sex-matched normal healthy controls. Compared to the normal controls, the patients with chronic schizophrenia showed significantly worse cognitive performance on verbal and visual memory tests, verbal fluency tests, and the Trail Making Test. The ratio of N-acetylaspartate to creatine and phosphocreatine (NAA/Cr) in the PCG of the patients was significantly lower than that of the controls. Moreover, the NAA/Cr in the PCG of the healthy controls exhibited age-related decline, whereas in the patients with schizophrenia, the corresponding values were consistently low, regardless of age. These findings are thus in accord with current speculation about neuronal dysfunction in the PCG based on the NMDA hypofunction hypothesis regarding the pathophysiology of chronic schizophrenia.

No changes in serum epidermal growth factor levels in patients with schizophrenia.

A recent report demonstrated that serum levels of epidermal growth factor (EGF) were significantly decreased in patients with schizophrenia, suggesting that impaired EGF signaling might be associated with the pathophysiology of schizophrenia. Our goal in the present study was to determine whether serum levels of EGF are altered in patients with schizophrenia. We found that serum levels of EGF in drug-naive (n = 15) or medicated patients (n = 25) with schizophrenia did not differ from those of age- and sex-matched normal controls (n = 40). However, we found a significant correlation between serum EGF levels and BPRS scores in the combined groups of patients. Therefore, our results do not support the claim that EGF plays a role in the pathogenesis of schizophrenia, but they suggest that EGF may serve as a state marker, that is, as an index of symptom-linked deficits.

Tropisetron improves deficits in auditory P50 suppression in schizophrenia.

Physiological deficits in inhibition of the P50 auditory evoked potential in schizophrenia have been related to diminished expression of alpha7 nicotinic acetylcholine receptors. Diminished P50 inhibition is correlated with neuropsychological deficits in attention, one of the principal neurocognitive disturbances in schizophrenia. Nicotine administration improves P50 inhibition, presumably by achieving additional activation of these diminished receptors, but its toxicity and marked tachyphylaxis make it an ineffective therapeutic. Nicotine also has weak positive effects on several neurocognitive deficits in schizophrenia, which raises the possibility that the alpha7 nicotinic receptor is a clinically relevant therapeutic target that should be addressed by less toxic agents. Tropisetron, a drug already approved for clinical use outside the United States as an anti-emetic, is a partial agonist at alpha7 nicotinic receptors and an antagonist at 5-HT(3) receptors. As an initial proof-of-principle study, we determined that a single administration of tropisetron significantly improves P50 inhibition in schizophrenia. These data are consistent with biological activity at a pathophysiological mechanism in schizophrenia and support further trials of this drug as a possible therapeutic for neurocognitive deficits in schizophrenia.

Increased midkine levels in sera from patients with Alzheimer's disease.

Midkine (MK) is a heparin binding growth factor and promotes growth, survival and migration of various cells including neurons. It is also known to accumulate in senile plaques of patients with Alzheimer's disease (AD). To investigate the involvement of serum MK in the pathophysiology of AD, serum MK levels were determined in patients with AD (n=36) and age- and sex-matched healthy controls (n=32), using an enzyme-linked immunosorbent assay (ELISA). The serum MK values of the patients with AD (median 560 and interquartile range (500-755) pg/ml) were significantly (U=278.5, P=0.0003, Mann-Whitney U-test) higher than those of the controls (median 500 and interquartile range (385-520) pg/ml). Moreover, 17 patients (47.2%) had abnormally high values of more than 600 pg/ml, but no controls (0%) did. There was no correlation between serum MK level and the mini mental state examination (MMSE) score in the patients. The demonstration of elevated MK levels in sera of patients with AD may contribute toward an understanding the pathophysiology of this disease, and provide a novel potential therapeutic strategy for decreasing neuronal damages in patients with AD. We found that serum MK levels in patients with AD were increased in comparison with those of normal controls.

No association of the brain-derived neurotrophic factor (BDNF) gene polymorphisms with panic disorder.

Several lines of evidence suggest that genetic factors might contribute to susceptibility to panic disorder. Our previous studies show that the brain-derived neurotrophic factor (BDNF) may play a role in the pathophysiology of major depressive disorders and eating disorders. Assuming that BDNF may be implicated in the putative common pathophysiology of depression and anxiety, we analyzed the association of two BDNF gene single nucleotide polymorphisms (SNPs), 132C > T (formerly named C270T) in the noncoding region of exon V and 196G > A (val66met) in the coding region of exon XIIIA, with panic disorder. In this study, 109 patients with panic disorder diagnosed according to the DSM-IV criteria, and 178 control subjects were recruited. There were no significant differences in the frequency of the genotype or allele in these two SNPs between patients and controls [132C > T in exon V: genotype, p = 1.0, allele, p = 0.59; 196G > A (val66met) in exon XIIIA: genotype, p = 0.77, allele, p = 0.78]. Furthermore, no significant associations of agoraphobia with the two SNPs were detected. This study suggests that the BDNF gene polymorphisms are not associated with panic disorder in our Japanese population.

Lack of association between angiotensin I-converting enzyme insertion/deletion gene functional polymorphism and panic disorder in humans.

Family and twin studies have indicated that genes influence susceptibility to panic disorder, but the genes involved remain unknown. The neuropeptide angiotensin II has been found to be involved in anxiety and regulation of respiration which are important in the pathophysiology of panic attacks. Assuming that angiotensins may be candidate genes in panic disorder, we analyzed the association between panic disorder and angiotensin I-converting enzyme (ACE) insertion (I)/deletion (D) gene functional polymorphism. We recruited 101 patients with panic disorder diagnosed according to DSM-IV criteria, and 184 control subjects in the study. No significant differences in the frequency of the genotype or allele in the polymorphism between patient and control groups were found (genotype, chi(2)=0.56, d.f.=2, P=0.77; allele, chi(2)=0.074, d.f.=1, P=0.78). This study suggests that the ACE I/D gene polymorphism is not directly associated with panic disorder in our Japanese patient group.

Decreased cell proliferation in the dentate gyrus of alpha 7 nicotinic acetylcholine receptor heterozygous mice.

It is suggested that deficits of alpha 7 nicotinic acetylcholine receptors (nAChRs) might be associated with the cognitive impairments of Alzheimer's disease and schizophrenia, and that agonists for alpha 7 nAChR could be useful for treatment of cognitive dysfunction in these diseases. This study was undertaken to examine the role of alpha 7 nAChRs on hippocampal cellular proliferation of adult mice. The number of 5-bromo-2'-deoxyuridine (BrdU)-immunoreactive cells in the granule cell layer (GCL) and hilus of alpha 7 nAChR heterozygous (+/-) mice was significantly decreased as compared with that of wild-type (+/+) mice. In contrast, the number of BrdU-immunoreactive cells in GCL and hilus of alpha 7 nAChR homozygous (-/-) mice was not different from that of wild-type mice. The results suggest that reduced levels of alpha 7 nAChRs may decrease cell proliferation of adult hippocampus.

Possible role of D-serine in the pathophysiology of Alzheimer's disease.

Several lines of evidence suggest that D-serine may function as an endogenous agonist of the glycine site on the N-methyl-D-aspartate (NMDA) receptor that has been implicated in the pathophysiology of Alzheimer's disease (AD). The purpose of the study was to determine whether serum levels of D- and L-serine in patients with AD are altered as compared with normal controls. Serum levels of D- and L-serine in patients of AD and age- and gender-matched normal controls were determined using a high-performance liquid chromatography (HPLC). Serum levels of D-serine in the patients with AD were slightly (z=-1.77, p=0.078) lower than those of normal controls. In contrast, serum levels of L-serine in the patients were slightly (z=-1.73, p=0.083) higher than those of controls. In addition, the percentage (%) of D-serine in the total (L+D) serine in the patients was significantly (z=-2.36, p=0.018) lower than that of controls. The present study suggests that the reduced activity of serine racemase, an enzyme catalyzing the formation of D-serine from L-serine may play a role in the pathophysiology of AD.

Adenosine A1 receptor agonists block the neuropathological changes in rat retrosplenial cortex after administration of the NMDA receptor antagonist dizocilpine.

Noncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist dizocilpine ((+)-MK-801) is known to induce neurotoxicity in rat retrosplenial cortex after systemic administration. The present study was undertaken to examine the effects of adenosine A(1) receptor agonists on the neurotoxicity in rat retrosplenial cortex after administration of dizocilpine. Pretreatment with adenosine A(1) receptor agonists, 2-chloro-N(6)-cyclopentyladenosine (CCPA) (0.1, 0.3, 1, or 3 mg/kg, intraperitoneally (i.p.)), or N(6)-cyclopentyladenosine (CPA) (1, 3, or 10 mg/kg, i.p.), attenuated neurotoxicity by dizocilpine (0.5 mg/kg, i.p), in a dose-dependent manner. Coadministration with adenosine A(1) receptor antagonist, 1,3-dipropyl-8-cyclopentylxanthine (DPCPX; 3 mg/kg, i.p.) significantly blocked the protective effects of CCPA for dizocilpine-induced neurotoxicity. Furthermore, pretreatment with CCPA (3 mg/kg) attenuated significantly the dizocilpine-induced expression of HSP-70 protein, which is known as a sensitive marker of reversible neuronal damage, and coadministration with DPCPX (3 mg/kg) blocked the inhibitory effects of CCPA for marked expression of HSP-70 protein by administration of dizocilpine. Moreover, pretreatment with CCPA (3 mg/kg, i.p.) significantly suppressed the increase of extracellular acetylcholine (ACh) levels in the retrosplenial cortex by administration of dizocilpine (0.5 mg/kg). In contrast, local perfusion of CCPA (1 microM) into the retrosplenial cortex via the dialysis probe did not alter the ACh levels by administration of dizocilpine (0.5 mg/kg), suggesting that the locus of action of CCPA is not in the retrosplenial cortex. These findings suggest that adenosine A(1) receptors agonists could protect against neuropathological changes in rat retrosplenial cortex after administration of the NMDA receptor antagonist dizocilpine.

Protective effect of LY379268, a selective group II metabotropic glutamate receptor agonist, on dizocilpine-induced neuropathological changes in rat retrosplenial cortex.

In the present study, we examined the effects of LY379268, the group II metabotropic glutamate receptor (mGluR) agonist, on the neuropathological changes in the rat retrosplenial cortex induced by noncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist dizocilpine ((+)-MK-801). Administration of LY379268 (1, 3, 10 mg/kg, i.p.) reduced dizocilpine (0.5 mg/kg, i.p.)-induced neuropathological changes in the retrosplenial cortex, in a dose-dependent manner. Co-administration of LY379268 (10 mg/kg, i.p.) with group II mGluR antagonist LY341495 (5 mg/kg, i.p.) blocked the effects of LY379268. Furthermore, LY379268 (10 mg/kg, i.p.) significantly reduced the expression of heat shock protein HSP-70, a marker of reversible neuronal injury, in the rat retrosplenial cortex after administration of dizocilpine (0.5 mg/kg, i.p.). Moreover, pretreatment with LY379268 (10 mg/kg, i.p.) significantly suppressed the increase in extracellular acetylcholine (ACh) levels in the retrosplenial cortex induced by administration of dizocilpine (0.5 mg/kg, i.p.). These results suggest that LY379268 has a protective effect on the neurotoxicity in the rat retrosplenial cortex after administration of NMDA receptor antagonists such as dizocilpine.

Serum brain-derived neurotrophic factor (BDNF) levels in schizophrenia are indistinguishable from controls.

Our previous study showed that serum brain-derived neurotrophic factor (BDNF) was significantly decreased in the antidepressant-naive patients with major depressive disorders. However, it was still unclear whether serum BDNF level was altered in drug-naive patients with schizophrenia. Using ELISA, we measured serum BDNF levels in antipsychotic-naive (n=15) and medicated (n=25) patients with schizophrenia, and in age- and sex-matched normal controls (n=40). There were no significant differences in serum BDNF levels among antipsychotic-naive (n=15) and medicated (n=25) patients and normal controls (n=40). Possible factors such as duration of illness, age of onset, Brief Psychiatric Rating Scale scores, and chlorpromazine equivalent dosages of antipsychotics did not reveal any significant correlations with BDNF levels. Our results do not support the view that serum BDNF levels are associated with schizophrenia.

Increased levels of serum basic fibroblast growth factor in schizophrenia.

Basic fibroblast growth factor (bFGF) is a multifunctional growth factor that has been implicated in a variety of neurodevelopmental processes. The aim of the present study was to examine whether bFGF contributes to the pathophysiology of schizophrenia. Serum bFGF levels in 40 patients with schizophrenia (15 drug-naive and 25 medicated patients) and in 40 age- and sex-matched healthy normal controls were measured. Serum bFGF levels were significantly higher in the medicated patients than in the normal controls. Analysis of partial correlation coefficients showed that the increased bFGF levels might not be attributable to antipsychotic medication. Although there was no significant overall difference in bFGF levels between drug-naive patients and normal controls, the bFGF levels in these patients significantly correlated with the severity of negative symptoms. Furthermore, we found a significant negative correlation between serum bFGF levels and the age of onset in the entire patient group. Our finding of elevated bFGF levels in the serum of patients with schizophrenia, especially in earlier age-of-onset cases considered to have more neurodevelopmental insults, suggests that bFGF abnormalities may be involved in the pathophysiology of schizophrenia.

Decreased levels of serum brain-derived neurotrophic factor in female patients with eating disorders.

BACKGROUND: Several lines of evidence suggest that brain-derived neurotrophic factor (BDNF) plays a role in the regulation of eating behavior. Because of its role in eating behavior, which is especially relevant to eating disorders, BDNF is an attractive candidate for investigation of potential biological markers of eating disorders such as bulimia nervosa (BN) and anorexia nervosa (AN). METHODS: We enrolled 18 female patients with BN, 12 female patients with AN, and 21 age-matched female normal control subjects in this study. Eating-related psychopathology and depressive symptoms were evaluated using the Bulimic Investigatory Test, Edinburgh (BITE) and the Hamilton Depression Rating Scale (HDRS). Serum BDNF levels were measured by a sandwich enzyme-linked immunosorbent assay. RESULTS: Serum levels of BDNF in the patients with AN or BN were significantly (p<.0001) decreased compared with those of normal control subjects, and serum BDNF levels in the patients with AN were significantly (p=.027) lower than those in patients with BN. A significant positive correlation (r=.378, p=.006) between serum BDNF levels and body mass index in all of the subjects was detected. Furthermore, there was a significant positive correlation (r=.435, p=.015) between the BITE symptom scale score and HDRS in these patients. CONCLUSIONS: The present study suggests that BDNF may play a role in the pathophysiology of eating disorders.

Alterations of serum levels of brain-derived neurotrophic factor (BDNF) in depressed patients with or without antidepressants.

BACKGROUND: Because researchers have reported that antidepressants increase the expression of brain-derived neurotrophic factor (BDNF) in the rat hippocampus, we investigated whether serum BDNF levels may be used as a putative biological marker for major depressive disorders (MDD). METHODS: We measured serum BDNF in the following three groups: antidepressant-naive patients with MDD (n = 16), antidepressant-treated patients with MDD (n = 17), and normal control subjects (n = 50). Patients were evaluated using the Hamilton Rating Scale for Depression (HAM-D). Serum BDNF was assayed with the sandwich ELISA method. RESULTS: We found that serum BDNF was significantly lower in the antidepressant-naive group (mean, 17.6 ng/mL; SD, 9.6) than in the treated (mean, 30.6 ng/mL; SD, 12.3; p =.001) or in the control group (mean, 27.7 ng/mL; SD, 11.4; p =.002). There was a significant negative correlation (r = -.350, z = -2.003, p =.045) between serum BDNF and HAM-D scores in all patients. In a preliminary examination, reduced BDNF values of three drug-naive patients recovered to basal levels after antidepressant treatment. CONCLUSIONS: Our study suggests that low BDNF levels may play a pivotal role in the pathophysiology of MDD and that antidepressants may increase BDNF in depressed patients.

Decreased serum levels of D-serine in patients with schizophrenia: evidence in support of the N-methyl-D-aspartate receptor hypofunction hypothesis of schizophrenia.

BACKGROUND: The hypofunction of the N-methyl-D-aspartate (NMDA) subtype of glutamate receptors has been implicated in the pathophysiology of schizophrenia. Several lines of evidence suggest that D-serine may function as an endogenous agonist of the glycine site of the NMDA receptor. The aim of this study was to examine whether serum levels of D- and L-serine in patients with schizophrenia are different from those of healthy controls. METHODS: Forty-two patients with schizophrenia and 42 age- and sex-matched healthy controls were enrolled in this study. Symptoms were assessed using the Brief Psychiatric Rating Scale. Serum levels of total serine and D- and L-serine were measured by high-performance liquid chromatography. RESULTS: Serum levels of D-serine in the patients with schizophrenia were significantly (z = -3.30, P =.001) lower than those of healthy controls. In contrast, serum levels of total (D and L) serine (z = -2.40, P =.02) and L-serine (z = -2.49, P =.01) in the schizophrenic patients were significantly higher than those of controls. In addition, the percentage of D-serine in the total serine in the schizophrenic patients was significantly (z = -4.78, P<.001) lower than that of controls, suggesting that the activity of serine racemase, an enzyme catalyzing the formation of D-serine from L-serine, may have been reduced in the schizophrenic patients. CONCLUSIONS: Reduced levels of D-serine may play a role in the pathophysiology of schizophrenia, and serum D- and L-serine levels might provide a measurable biological marker for schizophrenia.