Effects of Subdiaphragmatic Vagotomy in the MPTP-induced Neurotoxicity in the Striatum and Colon of Mice

Objective@#Gut—microbiota—brain axis plays a role in the pathogenesis of Parkinson’s disease (PD). The subdiaphragmatic vagus nerve serves as a major modulatory pathway between the gut microbiota and the brain. However, the role of subdiaphragmatic vagus nerve in PD pathogenesis are unknown. Here, we investigated the effects of subdiaphragmatic vagotomy (SDV) on the neurotoxicity in the mouse striatum and colon after administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). @*Methods@#Sham or SVD was performed. Subsequently, saline or MPTP (10 mg/kg × 3, 2-hour interval) was administered to mice. Western blot analysis of tyrosine hydroxylase (TH) and dopamine transporter (DAT) in the striatum and phosphorylated α-synuclein (p-α-Syn) in the colon was performed. @*Results@#Repeated administration of MPTP significantly caused reduction of TH and DAT in the striatum and increase of p-α-Syn in the colon of mice. However, SDV did not affect the reduction of TH and DAT in the striatum and increases in p-α-Syn in the colon after repeated MPTP administration. @*Conclusion@#These data suggest that subdiaphragmatic vagus nerve doses not play a role in the MPTP-induced neurotoxicity in the brain and colon.

Autism-like Behaviors in Male Juvenile Offspring after Maternal Glyphosate Exposure

Objective@#Exposure to the herbicide glyphosate during pregnancy and lactation may increase the risk for autism spectrum disorder (ASD) in offspring. Recently, we reported that maternal exposure of formulated glyphosate caused ASD-like behaviors in juvenile offspring. Here, we investigated whether maternal exposure of pure glyphosate could cause ASD-like behaviors in juvenile offspring. @*Methods@#Water or 0.098% glyphosate was administered as drinking water from E5 to P21 (weaning). Behavioral tests such as grooming test and three-chamber social interaction test in male offspring were performed from P28 to P35. @*Results@#Male offspring showed ASD-like behavioral abnormalities (i.e., increasing grooming behavior and social interaction deficit) after maternal exposure of glyphosate. @*Conclusion@#The findings suggest that the exposure of glyphosate during pregnancy and lactation may cause ASD-like behavioral abnormalities in male juvenile offspring. It is likely that glyphosate itself, but not the other ingredients, may contribute to ASD-like behavioral abnormalities in juvenile offspring.

Autism-like Behaviors in Male Juvenile Offspring after Maternal Glyphosate Exposure

Objective@#Exposure to the herbicide glyphosate during pregnancy and lactation may increase the risk for autism spectrum disorder (ASD) in offspring. Recently, we reported that maternal exposure of formulated glyphosate caused ASD-like behaviors in juvenile offspring. Here, we investigated whether maternal exposure of pure glyphosate could cause ASD-like behaviors in juvenile offspring. @*Methods@#Water or 0.098% glyphosate was administered as drinking water from E5 to P21 (weaning). Behavioral tests such as grooming test and three-chamber social interaction test in male offspring were performed from P28 to P35. @*Results@#Male offspring showed ASD-like behavioral abnormalities (i.e., increasing grooming behavior and social interaction deficit) after maternal exposure of glyphosate. @*Conclusion@#The findings suggest that the exposure of glyphosate during pregnancy and lactation may cause ASD-like behavioral abnormalities in male juvenile offspring. It is likely that glyphosate itself, but not the other ingredients, may contribute to ASD-like behavioral abnormalities in juvenile offspring.

Increased Levels of C1q in the Prefrontal Cortex of Adult Offspring after Maternal Immune Activation: Prevention by 7,8-Dihydroxyflavone

OBJECTIVE: Prenatal infection is implicated in the etiology of schizophrenia. The objective of this paper is to study the role of complement protein C1q in the psychosis of adult offspring after maternal immune activation (MIA). In addition, effect of 7,8-dihydroxyflavone (7,8-DHF: a tropomyosin receptor kinase B [TrkB] agonist) was also examined. METHODS: Western blot analysis of C1q in the brain regions from adult offspring after prenatal poly(I:C) (5.0 mg/kg/day from E12 to E17) exposure was performed. 7,8-DHF or vehicle was given from 4 to 8-weeks old. RESULTS: Expression of C1q in the prefrontal cortex (PFC) of adult offspring from poly(I:C)-treated pregnant mice was significantly higher than that of control group. Early treatment with 7,8-DHF during juvenile and adolescent stages could prevent an increase of C1q in the PFC of adult offspring after MIA. CONCLUSION: Therefore, it is likely that increased C1q expression in the frontal cortex may play a role in the behavioral abnormalities of adult offspring after MIA. Furthermore, supplementation with a TrkB agonist such as 7,8-DHF during the prodromal stage may have prophylactic effects on the behavioral abnormalities after MIA.

Reduction of Severity of Recurrent Psychotic Episode by Sustained Treatment with Aripiprazole in a Schizophrenic Patient with Dopamine Supersensitivity: A Case Report

Dopamine supersensitivity psychosis (DSP) is a type of acute exacerbation of recurrent psychosis caused by long-term treatment with antipsychotics in schizophrenic patients. Although DSP is exceedingly troublesome for clinicians, effective treatment has not yet been established. Based on clinical research and our animal study, we hypothesize that aripiprazole, an atypical anti-psychotic, may reduce the exacerbation of recurrent psychotic episodes. We report the case of a 46-year-old female who suffered from schizophrenia with DSP. In this case, sustained treatment with a high dose of aripiprazole gradually reduced the severity of her recurrent psychotic episodes. In conclusion, sustained treatment with aripiprazole may reduce the exacerbation of recurrent psychotic episodes in schizophrenic patients with DSP, and may be an effective treatment of DSP.

Early Intervention for Psychosis with N-Methyl-D-Aspartate Receptor Modulators

No abstract available.

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

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.

Combination of Nitrous Oxide with Isoflurane or Scopolamine for Treatment-resistant Major Depression

No abstract available.

Effects of Brilliant Blue G on Serum Tumor Necrosis Factor-alpha Levels and Depression-like Behavior in Mice after Lipopolysaccharide Administration

OBJECTIVE: Accumulating evidence suggests that inflammation plays a role in the pathophysiology of major depression. The adenosine triphosphate (ATP)-sensitive P2X7 receptor (P2X7R) plays a crucial role in microglial activation caused by inflammation. The dye brilliant blue G (BBG) is a P2X7R antagonist. This study examined whether BBG shows antidepressant effects in an inflammation-induced model of depression. METHODS: We examined the effects of BBG (12.5, 25, or 50 mg/kg) on serum tumor necrosis factor-alpha (TNF-alpha) levels after administering the bacterial endotoxin lipopolysaccharide (LPS; 0.5 mg/kg) and the effects of BBG (50 mg/kg) on depression-like behavior in the tail-suspension test (TST) and forced swimming test (FST). RESULTS: Pretreatment with BBG (12.5, 25, or 50 mg/kg) significantly blocked the increase in serum TNF-alpha levels after a single dose of LPS (0.5 mg/kg). Furthermore, BBG (50 mg/kg) significantly attenuated the increase in immobility time in the TST and FST after LPS (0.5 mg/kg) administration. CONCLUSION: The results suggest that BBG has anti-inflammatory and antidepressant effects in mice after LPS administration. Therefore, P2X7R antagonists are potential therapeutic drugs for inflammation-related major depression.

The R-Stereoisomer of Ketamine as an Alternative for Ketamine for Treatment-resistant Major Depression

No abstract available.

Antidepressant Effects of Ketamine on Depression-like Behavior in Juvenile Mice after Neonatal Dexamethasone Exposure

OBJECTIVE: Pediatric depression is associated with significant functional impairment at school and at work. Recently, we reported on depression-like behavior in juvenile mice neonatally exposed to dexamethasone (DEX) as a potential animal model for pediatric depression. The N-methyl-D-aspartate (NMDA) receptor antagonist ketamine has promoted rapid and long-lasting antidepressant effects in patients with treatment-resistant major depression. This study was conducted to examine whether ketamine had antidepressant effects in juvenile mice after neonatal DEX exposure. METHODS: A single dose (10 mg/kg) of ketamine or vehicle was injected into juvenile mice at days 29-32 after neonatal DEX (or saline) exposure (days 1-3). The sucrose preference test, tail suspension test, and forced swimming test were performed 24, 40, and 46 hours, respectively, after injection of ketamine. RESULTS: Ketamine (10 mg/kg) significantly improved depression-like behavior in DEX-treated juvenile mice. CONCLUSION: This finding suggests that ketamine confers antidepressant effects in an animal model of pediatric depression.

Post-traumatic Stress Disorder Symptoms in a Female Patient Following Repeated Teasing: Treatment with Gabapentin and Lamotrigine and the Possible Role of Sensitization

Post-traumatic stress disorder (PTSD) is a pathological response to trauma characterized by frequent recollections, recurrent nightmares, and flashbacks of the traumatic event(s). To date, the precise mechanisms underlying the development of PTSD remain unknown. Several studies have suggested that antiepileptic drugs, such as gabapentin and lamotrigine, may be effective in the treatment of PTSD symptoms. We report on a 15-year-old Japanese female junior high school student who developed PTSD symptoms following repeated teasing from male classmates. Additionally, we underscore the beneficial effects of treatment with gabapentin and lamotrigine on flashbacks and nightmares. This patient developed PTSD symptoms after repeated teasing from male classmates at school. Her flashbacks and nightmares were treated with a combination of gabapentin and lamotrigine. After recovery, treatment with lamotrigine alone controlled her symptoms. Our observations suggest that a process of sensitization may be involved in the development of PTSD symptoms. Additionally, gabapentin and/or lamotrigine were effective in the treatment of flashbacks and nightmares in this patient. Thus, doctors should consider using these anti-epileptic drugs as an alternative approach to treating PTSD symptoms.

Erratum: Figure Correction

The Figure 1A was given incorrectly.

Benefical Effects of Sigma-1 Agonist Fluvoxamine for Tardive Dyskinesia and Tardive Akathisia in Patients with Schizophrenia: Report of Three Cases

Fluvoxamine is a selective serotonin reuptake inhibitor that is approved for psychiatric disorders such as major depressive episodes and obsessive-compulsive disorder. Beside inhibition of serotonin reuptake, fluvoxamine is also a potent agonist of endoplasmic reticulum (ER) protein sigma-1 receptors, which play a role in the pathophysiology of a number of psychiatric and neurodegenerative disorders. This report presents beneficial effects of sigma-1 agonist fluvoxamine on hyperkinetic movement disorders such as tardive dyskinesia and tardive akathisia. Fluvoxamine might be a novel treatmet approach in the treatment of hyperkinetic movement disorders.

Potential Role of the Sigma-1 Receptor Chaperone in the Beneficial Effects of Donepezil in Dementia with Lewy Bodies

No abstract available.

Effects of the Antioxidant Sulforaphane on Hyperlocomotion and Prepulse Inhibition Deficits in Mice after Phencyclidine Administration

OBJECTIVE: Accumulating evidence suggests that oxidative stress plays a role in the pathophysiology of schizophrenia and that the potent antioxidants may be potential therapeutic drugs for schizophrenia. This study was undertaken to examine the effects of the potent antioxidant sulforaphane (SFN), found in cruciferous vegetables, on behavioral abnormalities (e.g., hyperlocomotion and prepulse inhibition [PPI] deficits) in mice after a single administration of the N-methyl-D-aspartate (NMDA)-receptor antagonist phencyclidine (PCP). METHODS: Effects of SFN (3, 10, and 30 mg/kg, intraperitoneally [i.p.]) on hyperlocomotion and PPI deficits in the adult male ddY mice after administration of PCP (3.0 mg/kg, subcutaneously [s.c.]) were examined. RESULTS: Administration of SFN (30 mg/kg, intraperitoneally [i.p.]), but not low doses (3 and 10 mg/kg, i.p.), significantly attenuated hyperlocomotion in mice after PCP administration (3.0 mg/kg, subcutaneously [s.c.]). Furthermore, administration of SFN (3, 10, and 30 mg/kg, i.p.) attenuated the PPI deficits in mice after PCP administration (3.0 mg/kg, s.c.) in a dose-dependent manner. CONCLUSION: These results suggest that SFN has antipsychotic activity in an animal model of schizophrenia. Therefore, it is likely that SFN may be a potential therapeutic drug for schizophrenia.

In Vivo Evaluation of 11C-labeled Three Radioligands for Glycine Transporter 1 in the Mouse Brain

OBJECTIVE: Glycine transporter 1 (GlyT-1) is one of the most attractive therapeutic targets for schizophrenia. There is great interest in developing radioligands for in vivo imaging of GlyT-1 in the brain using positron emission tomography. Here, we report the properties of three novel non-sarcosine-based radioligands [11C]CHIBA-3007, [11C]CHIBA-3009, and [11C]CHIBA-3011, for GlyT-1 imaging in the mouse brain in vivo. METHODS: The three radioligands were synthesized by N-[11C] methylation of the corresponding desmethyl precursor. A pharmacological characterization of these radioligands for in vivo imaging of GlyT-1 in the brain was conducted using male ddY mice. RESULTS: [11C]CHIBA-3009 and [11C]CHIBA-3011 were scarcely incorporated into the brain, whereas [11C]CHIBA-3007 showed slight but considerable brain uptake. Regional brain uptake of [11C]CHIBA-3007 (medulla oblongata>cerebellum>cortex) was similar to the distribution of the GlyT-1 protein. However, pretreatment with CHIBA-3007 (1 mg/kg) or the GlyT-1 selective inhibitor ALX5407 (N-[(3R)-3-([1,1'-Biphenyl]-4-yloxy)-3-(4-fluorophenyl)propyl]-N-methylglycine) (30 mg/kg) did not significantly decrease brain uptake of [11C]CHIBA-3007, suggesting low specific binding to GlyT-1. Pretreatment with cyclosporin A significantly increased brain uptake of [11C]CHIBA-3009 and [11C]CHIBA-3011, suggesting a role for P-glycoprotein in the brain uptake of these ligands. All three radioligands were rapidly degraded intact forms were 3-18% in plasma and 15-74% in the brain at 15 min after injection. CONCLUSION: The results suggest that these three radioligands are not suitable for in vivo imaging of GlyT-1 in the brain because of low brain uptake and rapid metabolism. Further structural refinement is necessary to enhance brain uptake.

A BDNF Val66Met Polymorphism and Ketamine-induced Rapid Antidepressant Action

No abstract available.

Occupancy of alpha7 Nicotinic Acetylcholine Receptors in the Brain by Tropisetron: A Positron Emission Tomography Study Using 11CCHIBA-1001 in Healthy Human Subjects

OBJECTIVE: Agonists of alpha7-nicotinic acetylcholine receptors (nAChRs) have been developed as potential therapeutic drugs for neuropsychiatric diseases such as schizophrenia and Alzheimer's disease. Positron emission tomography (PET) is a noninvasive brain imaging technique to measure receptor occupancy in the living human brain. Although much effort has been expended to create specific PET radioligands for alpha7-nAChRs in the brain, only 4-[11C]methylphenyl-1,4-diazabicyclo[3.2.2.]nonane-4-carboxylate ([11C]CHIBA-1001) is currently available for clinical studies. In contrast, two 5-hydroxytryptamine-3 (5-HT3) receptor antagonists, tropisetron and ondansetron, have been used to treat patients with chemotherapy-induced or postoperative nausea and vomiting. Furthermore, tropisetron, but not ondansetron, possesses high affinity for alpha7-nAChRs. In the present study, we evaluated the receptor occupancy in the human brain after a single oral administration of tropisetron and ondansetron using [11C]CHIBA-1001 and PET. METHODS: Two serial dynamic PET scans using [11C]CHIBA-1001 in healthy non-smoking male subjects were performed before and after receiving an oral administration of these medications. RESULTS: A single oral administration of tropisetron, but not ondansetron, decreased the total distribution volume of [11C]CHIBA-1001 in the human brain. CONCLUSION: This study shows that tropisetron, but not ondansetron, could bind to alpha7-nAChRs in the human brain after a single oral administration. Therefore, [11C]CHIBA-1001 may be a useful PET radioligand to measure the occupancy of alpha7-nAChRs in the human brain.