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We compared transcriptomic profiles of cerebral organoids differentiated from induced pluripotent stem cells of eight schizophrenia and eight bipolar disorder patients to identify genes that were differentially expressed in cerebral organoids between two disorders. Gene ontology analysis showed relative up-regulation in schizophrenia organoids of genes related to response to cytokines, antigen binding and clathrin-coated vesicles, while showing up-regulation in bipolar disorder of genes involved in calcium binding. Gene set enrichment analysis revealed enrichment in schizophrenia of genes involved in mitochondrial and oxidative phosphorylation while showing enrichment in bipolar disorder of genes involved in long term potentiation and neuro-transporters. We compared mitochondrial function in cerebral organoids from schizophrenia and bipolar disorder subjects and found that while schizophrenia organoids showed deficits in basal oxygen consumption rate and ATP production when compared to healthy control organoids, while bipolar disorder organoids did not show these deficits. Gene ontology analyses also revealed enrichment in bipolar disorder of genes in ion binding and regulation of transport. Experiments examining the interaction between mitochondria and endoplasmic reticulum in cortical neurons from bipolar disorder subjects showed a significantly lower number of contact sites between mitochondria and endoplasmic reticulum when compared to cortical neurons from schizophrenia patients. These results point to disease-specific deficits in mitochondrial respiration in schizophrenia and in mitochondrial-endoplasmic reticulum interactions in bipolar disorder. Supplementary Information: The online version contains supplementary material available at 10.1007/s44192-023-00031-8.
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BACKGROUND: Brain bioenergetic anomalies and redox dysregulation have been implicated in the pathophysiology of psychotic disorders. The present study examined brain energy-related metabolites and the balance between nicotinamide adenine dinucleotide metabolites (oxidized NAD+ and reduced NADH) using 31P-magnetic resonance spectroscopy (31P-MRS) in unaffected siblings, compared to first episode psychosis (FEP) patients and healthy controls. METHODS: 21 unaffected siblings, 32 FEP patients (including schizophrenia spectrum and affective psychoses), and 21 controls underwent 31P-MRS in the frontal lobe (6×6×4cm3) on a 4T MR scanner, using custom-designed dual-tuned surface coil with outer volume suppression. Brain parenchymal pH and steady-state metabolite ratios of high energy phosphate compounds were measured. NAD+ and NADH levels were determined using a 31P-MRS fitting algorithm. 13 unaffected sibling-patient pairs were related; other patients and siblings were unrelated. ANCOVA analyses were used to examine 31P-MRS measures, with age and gender as covariates. RESULTS: The phosphocreatine/adenosine triphosphate ratio was significantly reduced in both unaffected siblings and FEP patients, compared to controls. NAD+/NADH ratio was significantly reduced in patients compared to siblings and controls, with siblings showing a reduction in NAD+/NADH compared to controls that was not statistically significant. Compared to patients and controls, siblings showed significantly reduced levels of NAD+. Siblings did not differ from patients or controls on brain pH. DISCUSSION: Our results indicate that unaffected siblings show some, but not all the same abnormalities in brain energy metabolites and redox state as FEP patients. Thus, 31P-MRS studies may identify factors related both to risk and expression of psychosis.
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Transtorno Bipolar/metabolismo , Lobo Frontal/metabolismo , Espectroscopia de Ressonância Magnética , Transtornos Psicóticos/metabolismo , Esquizofrenia/metabolismo , Irmãos , Adolescente , Adulto , Transtorno Bipolar/diagnóstico por imagem , Transtorno Bipolar/tratamento farmacológico , Feminino , Lobo Frontal/diagnóstico por imagem , Humanos , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética/métodos , Masculino , NAD/metabolismo , Oxirredução , Isótopos de Fósforo , Transtornos Psicóticos/diagnóstico por imagem , Transtornos Psicóticos/tratamento farmacológico , Psicotrópicos/uso terapêutico , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/tratamento farmacológico , Adulto JovemRESUMO
A childhood history of attention deficit hyperactivity disorder (ADHD) is common in psychotic disorders, yet prescription stimulants may interact adversely with the physiology of these disorders. Specifically, exposure to stimulants leads to long-term increases in dopamine release. We therefore hypothesized that individuals with psychotic disorders previously exposed to prescription stimulants will have an earlier onset of psychosis. Age of onset of psychosis (AOP) was compared in individuals with and without prior exposure to prescription stimulants while controlling for potential confounding factors. In a sample of 205 patients recruited from an inpatient psychiatric unit, 40% (n = 82) reported use of stimulants prior to the onset of psychosis. Most participants were prescribed stimulants during childhood or adolescence for a diagnosis of ADHD. AOP was significantly earlier in those exposed to stimulants (20.5 vs. 24.6 years stimulants vs. no stimulants, p < 0.001). After controlling for gender, IQ, educational attainment, lifetime history of a cannabis use disorder or other drugs of abuse, and family history of a first-degree relative with psychosis, the association between stimulant exposure and earlier AOP remained significant. There was a significant gender × stimulant interaction with a greater reduction in AOP for females, whereas the smaller effect of stimulant use on AOP in males did not reach statistical significance. In conclusion, individuals with psychotic disorders exposed to prescription stimulants had an earlier onset of psychosis, and this relationship did not appear to be mediated by IQ or cannabis.
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Estimulantes do Sistema Nervoso Central/uso terapêutico , Transtornos Psicóticos/tratamento farmacológico , Transtornos Psicóticos/epidemiologia , Adulto , Idade de Início , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Transtorno Bipolar/tratamento farmacológico , Transtorno Bipolar/epidemiologia , Feminino , Humanos , Masculino , Análise de Regressão , Esquizofrenia/tratamento farmacológico , Esquizofrenia/epidemiologia , Fatores SexuaisRESUMO
Phosphorus magnetic resonance spectroscopy ((31)P MRS) allows in vivo quantification of phosphorus metabolites that are considered to be related to membrane turnover and energy metabolism. In schizophrenia (SZ), (31)P MRS studies found several abnormalities in different brain regions suggesting that alterations in these pathways may be contributing to the pathophysiology. In this paper, we systematically reviewed the (31)P MRS studies in SZ published to date by taking patient characteristics, medication status and brain regions into account. Publications written in English were searched on http://www.ncbi.nlm.nih.gov/pubmed/, by using the keywords 'phosphomonoester', 'phosphodiester', 'ATP', 'phosphocreatine', 'phosphocholine', 'phosphoethanolamine','glycerophosphocholine', 'glycerophosphoethanolamine', 'pH', 'schizophrenia', and 'MRS'. Studies that measured (31)P metabolites in SZ patients were included. This search identified 52 studies. Reduced PME and elevated PDE reported in earlier studies were not replicated in several subsequent studies. One relatively consistent pattern was a decrease in PDE in chronic patients in the subcortical structures. There were no consistent patterns for the comparison of energy related phosphorus metabolites between patients and controls. Also, no consistent pattern emerged in studies seeking relationship between (31)P metabolites and antipsychotic use and other clinical variables. Despite emerging patterns, methodological heterogeneities and shortcomings in this literature likely obscure consistent patterns among studies. We conclude with recommendations to improve study designs and (31)P MRS methods in future studies. We also stress the significance of probing into the dynamic changes in energy metabolism, as this approach reveals abnormalities that are not visible to steady-state measurements.
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Encéfalo/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Fósforo , Esquizofrenia/metabolismo , HumanosRESUMO
White matter (WM) abnormalities are among the most commonly reported neuroimaging findings in bipolar disorder. Nonetheless, the specific nature and pathophysiology of these abnormalities remain unclear. Use of a combination of magnetization transfer ratio (MTR) and diffusion tensor spectroscopy (DTS) permits examination of myelin and axon abnormalities separately. We aimed to examine myelination and axon geometry in euthymic patients with bipolar disorder with psychosis (BDP) by combining these two complementary noninvasive MRI techniques. We applied a combined MRI approach using MTR to study myelin content and DTS to study metabolite (N-acetylaspartate, NAA) diffusion within axons in patients with BDP (n=21) and healthy controls (n=24). Data were collected from a 1 × 3 × 3-cm voxel within the right prefrontal cortex WM at 4 Tesla. Clinical and cognitive data were examined in association with MTR and DTS data. MTR was significantly reduced in BDP, suggesting reduced myelin content. The apparent diffusion coefficient of NAA did not differ from healthy controls, suggesting no changes in axon geometry in patients with BDP. These findings suggest that patients with BDP exhibit reduced myelin content, but no changes in axon geometry compared with controls. These findings are in contrast with our recent findings, using the same techniques, in patients with schizophrenia (SZ), which suggest both myelination and axon abnormalities in SZ. This difference may indicate that alterations in WM in BDP may have unique causes and may be less extensive than WM abnormalities seen in SZ.
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Axônios/patologia , Transtorno Bipolar/patologia , Córtex Pré-Frontal/patologia , Substância Branca/patologia , Adulto , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Axônios/metabolismo , Transtorno Bipolar/complicações , Transtorno Bipolar/metabolismo , Imagem de Tensor de Difusão , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Córtex Pré-Frontal/metabolismo , Espectroscopia de Prótons por Ressonância Magnética , Escalas de Graduação Psiquiátrica , Transtornos Psicóticos/complicações , Transtornos Psicóticos/metabolismo , Transtornos Psicóticos/patologia , Substância Branca/metabolismoRESUMO
BACKGROUND: We previously reported rapid mood elevation following an experimental magnetic resonance imaging procedure in depressed patients with bipolar disorder (BPD). This prompted the design, construction, and testing of a portable electromagnetic device that reproduces only the rapidly oscillating (1 kHz, <1 V/m) electromagnetic field of the experimental procedure, called low field magnetic stimulation (LFMS). METHODS: We used a randomized, double blind, sham controlled treatment protocol to study the effects of LFMS in a large group of stably medicated, depressed patients with either BPD (n = 41) or major depressive disorder (n = 22). Subjects received a single, 20-minute treatment. Change in mood was assessed immediately afterward using a visual analog scale (VAS), the 17-item Hamilton Depression Rating Scale (HDRS-17), and the Positive and Negative Affect Schedule scales. RESULTS: Substantial improvement (>10% of baseline) in mood was observed following LFMS treatment relative to sham treatment for both diagnostic subgroups for our primary outcomes, the VAS and the HDRS-17. These differences were not statistically significant in primary analyses stratifying by diagnosis but were significant in secondary analyses combining data across the two diagnostic groups (p = .01 VAS, p = .02 HDRS-17). Rapid improvement in mood was also observed using the Positive and Negative Affect Schedule scales as secondary measures (positive affect scale p = .02 BPD, p = .002 combined group). A finite element method calculation indicates a broad penetration of the LFMS electric field throughout the cerebral cortex. CONCLUSIONS: Low field magnetic stimulation may produce rapid changes in mood using a previously unexplored range of electromagnetic fields.
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Afeto/fisiologia , Transtorno Bipolar/terapia , Encéfalo/fisiopatologia , Transtorno Depressivo Maior/terapia , Magnetoterapia/instrumentação , Adulto , Método Duplo-Cego , Campos Eletromagnéticos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
IMPORTANCE: Abnormalities in neural activity and cerebral bioenergetics have been observed in schizophrenia (SZ). Further defining energy metabolism anomalies would provide crucial information about molecular mechanisms underlying SZ and may be valuable for developing novel treatment strategies. OBJECTIVE: To investigate cerebral bioenergetics in SZ via measurement of creatine kinase activity using in vivo 31P magnetization transfer spectroscopy. DESIGN, SETTING, AND PARTICIPANTS: Cross-sectional case-control study in the setting of clinical services and a brain imaging center of an academic psychiatric hospital. Twenty-six participants with chronic SZ (including a subgroup diagnosed as having schizoaffective disorder) and 26 age-matched and sex-matched healthy control subjects (25 usable magnetic resonance spectroscopy data sets from the latter). INTERVENTION: 31P magnetization transfer spectroscopy. MAIN OUTCOMES AND MEASURES: The primary outcome measure was the forward rate constant (k(f)) of the creatine kinase enzyme in the frontal lobe. We also collected independent measures of brain intracellular pH and steady-state metabolite ratios of high-energy phosphate-containing compounds (phosphocreatine and adenosine triphosphate [ATP]), inorganic phosphate, and the 2 membrane phospholipids phosphodiester and phosphomonoester. RESULTS: A substantial (22%) and statistically significant (P = .003) reduction in creatine kinase kf was observed in SZ. In addition, intracellular pH was significantly reduced (7.00 in the SZ group vs 7.03 in the control group, P = .007) in this condition. The phosphocreatine to ATP ratio, inorganic phosphate to ATP ratio, and phosphomonoester to ATP ratio were not substantially altered in SZ, but a significant (P = .02) reduction was found in the phosphodiester to ATP ratio. The abnormalities were similar between SZ and schizoaffective disorder. CONCLUSIONS AND RELEVANCE: Using a novel 31P magnetization transfer magnetic resonance spectroscopy approach, we provide direct and compelling evidence for a specific bioenergetic abnormality in SZ. Reduced kf of the creatine kinase enzyme is consistent with an abnormality in storage and use of brain energy. The intracellular pH reduction suggests a relative increase in the contribution of glycolysis to ATP synthesis, providing convergent evidence for bioenergetic abnormalities in SZ. The similar phosphocreatine to ATP ratios in SZ and healthy controls suggest that the underlying bioenergetics abnormality is not associated with change in this metabolite ratio.
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Encéfalo/metabolismo , Metabolismo Energético/fisiologia , Espectroscopia de Ressonância Magnética , Esquizofrenia/metabolismo , Trifosfato de Adenosina/análise , Adulto , Encéfalo/fisiopatologia , Química Encefálica , Estudos de Casos e Controles , Creatina Quinase/metabolismo , Estudos Transversais , Feminino , Lobo Frontal/metabolismo , Lobo Frontal/fisiopatologia , Humanos , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética/métodos , Masculino , Fosfocreatina/análise , Isótopos de Fósforo/metabolismo , Esquizofrenia/fisiopatologiaRESUMO
Some drugs developed as anticonvulsants (notably, valproate and lamotrigine) have therapeutic effects in bipolar and related disorders. Lacosamide, a recently approved anticonvulsant, has unique effects on sodium channels that may play a role in producing the mood-stabilizing effects of anticonvulsant drugs. We tested whether lacosamide would have effects similar to or different from valproate and lamotrigine in a model of reward and elevated mood. The intracranial self-stimulation (ICSS) test is sensitive to the function of brain reward systems. Changes in ICSS may model aspects of disorders characterized by abnormalities of reward and motivation. Cocaine elevates mood, and reduction of cocaine-induced facilitation of ICSS has been used to predict antimanic-like or mood stabilizing effects of drugs. We tested lacosamide, lamotrigine, and valproate in the rat ICSS test alone or in the presence of cocaine. A high dose of lacosamide (30 mg/kg) significantly elevated ICSS thresholds, indicating that it reduced the rewarding impact of medial forebrain bundle stimulation. Lower doses (3-10 mg/kg) did not alter ICSS, but blocked the cocaine-induced lowering of ICSS thresholds. The highest doses of valproate (300 mg/kg) and lamotrigine (30 mg/kg) also elevated ICSS thresholds, and only these high doses significantly lowered cocaine-induced effects. Of the drugs tested, only lacosamide significantly attenuated the reward-facilitating effects of cocaine at doses that had no effects on ICSS response in the absence of cocaine. Abnormalities of mood and reward are common in psychiatric disorders, and these results suggest that lacosamide deserves further study in models of these disorders.
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Acetamidas/farmacologia , Anticonvulsivantes/farmacologia , Cocaína/farmacologia , Recompensa , Triazinas/farmacologia , Ácido Valproico/farmacologia , Animais , Lacosamida , Lamotrigina , Masculino , Ratos , Ratos Sprague-Dawley , Esquema de Reforço , Autoestimulação/efeitos dos fármacos , Autoestimulação/fisiologia , Resultado do TratamentoRESUMO
OBJECTIVE: This study aimed to test the effects of omega-3 fatty acids (O3FA), given as fish oil capsules, with and without oral cytidine (CYT), a pyrimidine with reported preclinical and clinical antidepressant-like effects, in patients with bipolar disorder (BD). METHODS: A total of 45 outpatients with diagnosed BD (type I) according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition - Text Revision, were recruited for this 4-month, randomized, double-blind, placebo-controlled, add-on study. Treatment groups were (1) oral CYT + O3FA, (2) placebo + O3FA, and (3) placebo + placebo control. O3FA was given 2 g twice a day and CYT was administered as 1 g twice a day. RESULTS: There was no statistically significant difference among the groups in the primary outcome: study retention. Clinical measures improved in all treatment groups, and there were no significant differences between groups, including change in probability of symptoms of depression or mania, change in positive ratings of depression or mania, or change in Global Assessment of Functioning scores. Neither CYT + O3FA nor placebo + O3FA treatment was superior to placebo treatment. Rather, there was a statistically nonsignificant trend for both groups treated with O3FA to do worse than the placebo group. CONCLUSIONS: Despite preclinical studies suggesting that the effect of O3FA might be augmented with pyrimidines, add-on CYT did not substantially improve mood symptoms in BD. In addition, although a power analysis indicated that the sample size would be adequate to see beneficial effects similar to those previously reported, O3FA treatment by itself was not superior to placebo for BD.
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Transtorno Bipolar/tratamento farmacológico , Citidina/uso terapêutico , Ácidos Graxos Ômega-3/uso terapêutico , Adulto , Transtorno Bipolar/fisiopatologia , Citidina/administração & dosagem , Método Duplo-Cego , Quimioterapia Combinada , Ácidos Graxos Ômega-3/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Falha de TratamentoRESUMO
INTRODUCTION: Despite the prevalence, associated comorbidities, and functional consequences of bipolar depression (BPD), underlying disease mechanisms remain unclear. Published studies of individuals with bipolar disorder implicate abnormalities in cellular energy metabolism. This study tests the hypotheses that the forward rate constant (k(for)) of creatine kinase (CK) is altered in older adults with BPD and that CoEnzyme Q10 (CoQ10), known to have properties that enhance mitochondrial function, increases k(for) in elderly individuals with BPD treated with CoQ10 compared with untreated age- and sex-matched controls. METHODS: Ten older adults (ages 55 and above) with Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition [DSM IV]) bipolar disorder, current episode depressed and 8 older controls underwent two 4 Tesla (31)Phosphorus magnetic resonance spectroscopy ((31)PMRS) scans 8 weeks apart using a magnetization transfer (MT) acquisition scheme to calculate k(for). The BPD group was treated with open-label CoEnzyme Q10 400 mg/d titrated up by 400 mg/d every 2 weeks to a maximum of 1200 mg/d. The Montgomery Asberg Depression Rating Scale (MADRS) was used to measure depression symptom severity. Baseline k(for) and changes in k(for) were compared between individuals with BPD and controls, not receiving CoQ. Clinical ratings were compared across time and associated with k(for) changes using repeated measures linear regression. RESULTS: The k(for) of CK was nonsignificantly lower for BPD than healthy controls at baseline (BPD mean (standard deviation [SD]) = 0.19 (0.02), control mean (SD) = 0.20 (0.02), Wilcoxon rank sum exact P = .40). The k(for) for both CoQ10-treated BPD and controls increased after 8 weeks (mean increase (SD) = 0.03 (0.04), Wilcoxon signed rank exact P = .01), with no significant difference in 8-week changes between groups (BPD mean change (SD) = 0.03 (0.03), control mean change (SD) = 0.03 (0.05), Wilcoxon rank sum exact P = .91). In an exploratory analysis, depression severity decreased with CoQ10 treatment in the group with BPD (F (3,7) = 4.87, P = .04) with significant reductions in the MADRS at weeks 2 (t (9) = -2.40, P = .04) and 4 (t (9) = -3.80, P = .004). CONCLUSIONS: This study employing the novel MRS technique of MT did not demonstrate significance between group differences in the k(for) of CK but did observe a trend that would require confirmation in a larger study. An exploratory analysis suggested a reduction in depression symptom severity during treatment with high-dose CoEnzyme Q10 for older adults with BPD. Further studies exploring alterations of high-energy phosphate metabolites in geriatric BPD and efficacy studies of CoQ10 in a randomized controlled trial are both warranted.
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Afeto/efeitos dos fármacos , Transtorno Bipolar/enzimologia , Creatina Quinase/metabolismo , Ubiquinona/análogos & derivados , Afeto/fisiologia , Idoso , Transtorno Bipolar/tratamento farmacológico , Encéfalo/efeitos dos fármacos , Encéfalo/enzimologia , Estudos de Casos e Controles , Creatina Quinase/efeitos dos fármacos , Creatina Quinase/fisiologia , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Estatísticas não Paramétricas , Ubiquinona/metabolismo , Ubiquinona/fisiologia , Ubiquinona/uso terapêuticoRESUMO
Multiple lines of evidence suggest that microstructural abnormalities in the white matter are important in the pathophysiology of schizophrenia. Diffusion MRI approaches which can provide evidence on tissue structure have been widely used to probe these abnormalities in vivo, but transverse relaxation times (T2) may provide additional insights since they are determined by molecule-microenvironment interactions not revealed by diffusion MRI. T2 of water - located both intra and extracellularly - and N-acetylaspartate (NAA - located intracellularly) reflect related but distinct processes due to their differential localization and interactions with other molecules. In this study, we collected water and NAA T2 data from 16 healthy subjects (HC), and 16 patients with schizophrenia (SZ) at 4 T in a 9 cm(3) voxel in the right prefrontal white matter. The SZ group had longer water but shorter NAA T2 relaxation times when compared with the HC group. This pattern resulted in a statistically significant metabolite×group interaction (F(18,1):4.980, p=0.039). Prolongation of water T2 and shortening of NAA T2 is consistent with an impoverishment of white matter macromolecule structures (including myelin) and abnormal intra-axonal milieu and volume in SZ.
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Ácido Aspártico/análogos & derivados , Encéfalo , Fibras Nervosas Mielinizadas/patologia , Relaxamento , Esquizofrenia/patologia , Água/metabolismo , Adolescente , Adulto , Análise de Variância , Ácido Aspártico/metabolismo , Encéfalo/metabolismo , Encéfalo/patologia , Encéfalo/fisiopatologia , Mapeamento Encefálico , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Esquizofrenia/metabolismo , Esquizofrenia/fisiopatologia , Fatores Sexuais , Adulto JovemRESUMO
Targeting the glutamatergic system has been suggested as a promising new option for developing treatment strategies for bipolar depression. Cytidine, a pyrimidine, may exert therapeutic effects through a pathway that leads to altered neuronal-glial glutamate cycling. Pyrimidines are also known to exert beneficial effects on cerebral phospholipid metabolism, catecholamine synthesis, and mitochondrial function, which have each been linked to the pathophysiology of bipolar depression. This study was aimed at determining cytidine's efficacy in bipolar depression and at assessing the longitudinal effects of cytidine on cerebral glutamate/glutamine levels. Thirty-five patients with bipolar depression were randomly assigned to receive the mood-stabilizing drug valproate plus either cytidine or placebo for 12 weeks. Midfrontal cerebral glutamate/glutamine levels were measured using proton magnetic resonance spectroscopy before and after 2, 4, and 12 weeks of oral cytidine administration. Cytidine supplementation was associated with an earlier improvement in depressive symptoms (weeks 1-4; p=0.02, 0.001, 0.002, and 0.004, respectively) and also produced a greater reduction in cerebral glutamate/glutamine levels in patients with bipolar depression (weeks 2, 4, and 12; p=0.004, 0.004, and 0.02, respectively). Cytidine-related glutamate/glutamine decrements correlated with a reduction in depressive symptoms (p=0.001). In contrast, these relationships were not observed in the placebo add-on group. The study results suggest that cytidine supplementation of valproate is associated with an earlier treatment response in bipolar depression. Furthermore, cytidine's efficacy in bipolar depression may be mediated by decreased levels of cerebral glutamate and/or glutamine, consistent with alterations in excitatory neurotransmission.
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Antidepressivos/uso terapêutico , Transtorno Bipolar , Encéfalo/metabolismo , Citidina/uso terapêutico , Ácido Glutâmico/metabolismo , Glutamina/metabolismo , Administração Oral , Adulto , Transtorno Bipolar/tratamento farmacológico , Transtorno Bipolar/metabolismo , Transtorno Bipolar/patologia , Encéfalo/efeitos dos fármacos , Distribuição de Qui-Quadrado , Método Duplo-Cego , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética/métodos , Pessoa de Meia-Idade , Prótons , Escalas de Graduação Psiquiátrica , Fatores de Tempo , Resultado do Tratamento , Adulto JovemRESUMO
BACKGROUND: Youths with bipolar disorder are ideal for studying illness pathophysiology given their early presentation, lack of extended treatment, and high genetic loading. Adult bipolar disorder MRI studies have focused increasingly on limbic structures and the thalamus because of their role in mood and cognition. On the basis of adult studies, the authors hypothesized a priori that youths with bipolar disorder would have amygdalar, hippocampal, and thalamic volume abnormalities. METHOD: Forty-three youths 6-16 years of age with DSM-IV bipolar disorder (23 male, 20 female) and 20 healthy comparison subjects (12 male, eight female) similar in age and sex underwent structured and clinical interviews, neurological examination, and cognitive testing. Differences in limbic and thalamic brain volumes, on the logarithmic scale, were tested using a two-way (diagnosis and sex) univariate analysis of variance, with total cerebral volume and age controlled. RESULTS: The subjects with bipolar disorder had smaller hippocampal volumes. Further analysis revealed that this effect was driven predominantly by the female bipolar disorder subjects. In addition, both male and female youths with bipolar disorder had significantly smaller cerebral volumes. No significant hemispheric effects were seen. CONCLUSIONS: These findings support the hypothesis that the limbic system, in particular the hippocampus, may be involved in the pathophysiology of pediatric bipolar disorder. While this report may represent the largest MRI study of pediatric bipolar disorder to date, more work is needed to confirm these findings and to determine if they are unique to pediatric bipolar disorder.
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Transtorno Bipolar/patologia , Sistema Límbico/patologia , Imageamento por Ressonância Magnética , Tálamo/patologia , Adolescente , Fatores Etários , Assistência Ambulatorial , Atrofia/patologia , Transtorno Bipolar/diagnóstico , Transtorno Bipolar/fisiopatologia , Mapeamento Encefálico , Criança , Feminino , Hipocampo/patologia , Hipocampo/fisiopatologia , Humanos , Processamento de Imagem Assistida por Computador , Sistema Límbico/fisiopatologia , Masculino , Tamanho do Órgão , Escalas de Graduação Psiquiátrica , Fatores Sexuais , Telencéfalo/patologia , Tálamo/anatomia & histologia , Tálamo/fisiopatologiaRESUMO
Salvinorin A is the only known non-nitrogenous and specific kappa-opioid agonist. A series of salvinorin A derivatives were prepared and tested for in vitro activity at the kappa-opioid receptor. Unsubstituted carbamate 9 was a potent kappa-agonist (EC(50) = 6.2 nM) and should be more stable than salvinorin A toward metabolic transformations. Compound 10, containing an N-methyl carbamate at C(2), showed partial agonist activity with 81% efficacy when compared with the full agonist U50,488H. No antagonist ligands were observed.
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Diterpenos/síntese química , Diterpenos/farmacologia , Animais , Células CHO , Cricetinae , Diterpenos/química , Diterpenos Clerodânicos , Avaliação Pré-Clínica de MedicamentosRESUMO
BACKGROUND: Brain phospholipid metabolism and membrane fluidity may be involved in the pathophysiology of mood disorders. We showed previously that cytidine, which increases phospholipid synthesis, has antidepressant-like effects in the forced swim test (FST) in rats, a model used in depression research. Because cytidine and uridine both stimulate synthesis of cytidine 5'-diphosphocholine (CDP-choline, a critical substrate for phospholipid synthesis), we examined whether uridine would also produce antidepressant-like effects in rats. We also examined the effects of omega-3 fatty acids (OMG), which increase membrane fluidity and reportedly have antidepressant effects in humans, alone and in combination with uridine. METHODS: We first examined the effects of uridine injections alone and dietary supplementation with OMG alone in the FST. We then combined sub-effective treatment regimens of uridine and OMG to determine whether these agents would be more effective if administered together. RESULTS: Uridine dose-dependently reduced immobility in the FST, an antidepressant-like effect. Dietary supplementation with OMG reduced immobility when given for 30 days, but not for 3 or 10 days. A sub-effective dose of uridine reduced immobility in rats given sub-effective dietary supplementation with OMG. CONCLUSIONS: Uridine and OMG each have antidepressant-like effects in rats. Less of each agent is required for effectiveness when the treatments are administered together.
Assuntos
Antidepressivos/uso terapêutico , Depressão/tratamento farmacológico , Ácidos Graxos Ômega-3/administração & dosagem , Natação/psicologia , Uridina/uso terapêutico , Animais , Antidepressivos/farmacologia , Comportamento Animal/efeitos dos fármacos , Depressão/dietoterapia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Vias de Administração de Medicamentos , Sinergismo Farmacológico , Quimioterapia Combinada , Resposta de Imobilidade Tônica/efeitos dos fármacos , Masculino , Atividade Motora/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Tempo de Reação/efeitos dos fármacos , Fatores de TempoRESUMO
STUDY OBJECTIVE: To determine if S-adenosyl-L-methionine (SAMe), a widely used dietary supplement with antidepressant properties, is significantly bioavailable, and whether toxic methylated compounds are produced with oral SAMe administration in humans. Serum homocysteine levels were also measured since alterations in these levels have been theorized in association with SAMe. DESIGN: Unblinded pharmacokinetic trial. SUBJECTS: Fifteen healthy volunteers. SETTING: Clinical research unit in a psychiatric hospital. INTERVENTION: Subjects received oral SAMe for 4 weeks; the dosage was titrated over 5 days to 1600 mg/day. Serum levels of SAMe, toxic methylated compounds (methanol, formaldehyde, and formic acid), and homocysteine were measured at baseline and at weeks 2 and 4. At baseline, a structured clinical interview for axis I disorders (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition) was completed to assess for any undiagnosed psychiatric disorders. Mood was rated at baseline and at weeks 2 and 4 using the Zung Depression Rating Scale, Young Mania Rating Scale, Montgomery-Asberg Depression Rating Scale, Clinical Global Impression Scale, and the Global Assessment of Function Scale. MEASUREMENTS AND MAIN RESULTS: After oral administration, SAMe levels were significantly elevated. Slight, likely insignificant, elevations in serum formaldehyde levels were detected in three subjects. No subject exhibited elevated homocysteine levels during SAMe treatment. One subject developed a transient mixed manic state with suicidal ideation within 2 weeks of starting SAMe; she recovered fully within 3 days of discontinuing the compound. CONCLUSION: Oral dosages of 1600 mg/day of SAMe appear to be significantly bioavailable and nontoxic, at least regarding toxic methylated metabolites and homocysteine. However, the risk of mania in vulnerable individuals remains a serious concern.
Assuntos
Homocisteína/biossíntese , S-Adenosilmetionina/farmacocinética , Administração Oral , Adulto , Disponibilidade Biológica , Transtorno Bipolar/induzido quimicamente , Feminino , Formaldeído/sangue , Formiatos/sangue , Humanos , Masculino , S-Adenosilmetionina/efeitos adversos , S-Adenosilmetionina/sangueRESUMO
OBJECTIVE: The authors hypothesized that changes in brain membrane composition resulting from omega-3 fatty acid administration in patients with bipolar disorder would result in greater membrane fluidity, as detected by reductions in T(2) values. METHOD: Women with bipolar disorder (N=12) received omega-3 fatty acids for 4 weeks. A cohort of bipolar subjects (N=9) and a group without bipolar disorder (N=12) did not receive omega-3 fatty acids. T(2) values were acquired at baseline and after 4 weeks. RESULTS: Bipolar subjects who received omega-3 fatty acids had significant decreases in T(2). There was a dose-dependent effect when the bipolar omega-3 fatty acid group was subdivided into high- and low-dose cohorts. CONCLUSIONS: Omega-3 fatty acids lowered T(2) values, consistent with the hypothesis that the fluidity of cell membranes was altered. Further studies are needed to clarify the significance of alterations in brain physiology induced by omega-3 fatty acids, as reflected in T(2) values.
Assuntos
Transtorno Bipolar/metabolismo , Encéfalo/metabolismo , Ácidos Graxos Ômega-3/uso terapêutico , Imageamento por Ressonância Magnética/estatística & dados numéricos , Fluidez de Membrana/efeitos dos fármacos , Adulto , Antipsicóticos/uso terapêutico , Transtorno Bipolar/dietoterapia , Água Corporal/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/fisiologia , Estudos de Coortes , Terapia Combinada , Relação Dose-Resposta a Droga , Ácidos Graxos Ômega-3/farmacologia , Feminino , Humanos , Fluidez de Membrana/fisiologia , Placebos , Resultado do TratamentoRESUMO
BACKGROUND: S-adenosyl-L-methionine is an effective treatment for clinical depression, although the mechanism underlying this effect is unclear. Presently, in vivo phosphorus magnetic resonance spectroscopy (31P MRS) and brain transverse relaxometry were employed to test if S-adenosyl-L-methionine supplementation alters brain bioenergetics and/or transverse relaxation time (T2RT) in a nondepressed cohort. If these magnetic resonance techniques are sensitive to S-adenosyl-L-methionine induced alterations in neurochemical processes, these methods may be used in cases of clinical depression to elucidate the mechanism underlying the antidepressant effect of S-adenosyl-L-methionine. METHODS: Twelve subjects self-administered 1600 mg of oral S-adenosyl-L-methionine daily. Phosphorus spectra and transverse relaxation time were acquired at baseline and after treatment using a 1.5 Tesla scanner. RESULTS: Phosphocreatine levels were significantly higher after treatment, whereas beta nucleoside triphosphate levels, predominantly adenosine triphosphate in brain, were significantly lower after treatment. A surprising gender difference in T2RT emerged after supplementation, with women exhibiting significantly lower T2RT than men. CONCLUSIONS: Alterations in phosphocreatine and beta nucleoside triphosphate are consistent with the report that S-adenosyl-L-methionine is involved in the production of creatine, which in turn is phosphorylated to phosphocreatine using adenosine triphosphate. These findings suggest that S-adenosyl-L-methionine alters parameters associated with cerebral bioenergetic status and that some effects of S-adenosyl-L-methionine (T2RT) occur in a gender-specific manner.
Assuntos
Antidepressivos/farmacocinética , Antidepressivos/uso terapêutico , Encéfalo/metabolismo , Transtorno Depressivo Maior/tratamento farmacológico , Metabolismo Energético/efeitos dos fármacos , Nível de Saúde , Relaxamento , S-Adenosilmetionina/farmacocinética , S-Adenosilmetionina/uso terapêutico , Trifosfato de Adenosina/biossíntese , Trifosfato de Adenosina/sangue , Administração Oral , Adulto , Antidepressivos/administração & dosagem , Encéfalo/irrigação sanguínea , Circulação Cerebrovascular/efeitos dos fármacos , Esquema de Medicação , Feminino , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Modelos Biológicos , Fosfocreatina/biossíntese , Fosfocreatina/sangue , Fósforo/farmacocinética , S-Adenosilmetionina/administração & dosagemRESUMO
Alterations in brain high-energy phosphate metabolism, determined by in vivo magnetic resonance spectroscopy (MRS), have been reported in subjects with a number of brain disorders including major depression, schizophrenia, and substance abuse. It is not clear to what extent these changes can be modified by pharmacological or nutritional means. To address this possibility, we evaluated changes in brain chemistry that were associated with oral creatine (Cr) administration. We hypothesized that oral Cr supplementation, by increasing brain creatine and high-energy phosphate stored in phosphocreatine, would result in an increase in the creatine resonance, as measured using proton 1H-MRS, and a decrease in the beta-nucleoside triphosphate (NTP) peak and an increase in the phosphocreatine (PCr) peak, as measured by phosphorus 31P-MRS, in brain of healthy human subjects. Fifteen healthy male subjects (age=22.9+/-2.2; body mass index=22.9+/-1.7), who were without any axis I disorders or physical or neurological illness, were recruited. Ten subjects took creatine-monohydrate, 0.3 g/kg/day for the first 7 days and 0.03 g/kg/day for the next 7 days (creatine group). Five comparison subjects took equivalent amounts of sucrose as placebo (placebo group). Both 1H- and 31P-MRS scans were acquired at baseline, as well as at day 7 and day 14 of oral supplementation. 1H-MRS: Water suppressed localized spectra were acquired using a single-voxel (1.5 cm x 2 cm x 2 cm) proton MRS PRESS sequence in the left frontal lobe. 31P-MRS: Phosphorus spectral data were recorded from a 5-cm-thick axial brain slice using a short-TE slice selective spin-echo pulse sequence. The creatine group had significantly increased brain creatine levels (8.1% and 9.3%, in creatine/N-acetyl aspartate and creatine/choline ratios, respectively) compared to the placebo group over the 2-week period. The creatine group had significantly decreased beta-NTP levels (7.8%) and marginally increased PCr (3.4%) over the same period. In addition, the brain inorganic phosphate level increased over the same period in the creatine group (9.8%). The current study is the first multinuclear (1H and 31P) MRS study to evaluate changes in brain high-energy phosphate metabolism following oral creatine supplementation in healthy human subjects. These findings suggest the possibility of using oral creatine supplementation to modify brain high-energy phosphate metabolism in subjects with various brain disorders, including major depression, schizophrenia, cocaine and opiate abuse, where alterations in brain high-energy phosphate metabolism have been reported.
Assuntos
Ácido Aspártico/análogos & derivados , Creatina/administração & dosagem , Metabolismo Energético/efeitos dos fármacos , Lobo Frontal/efeitos dos fármacos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética/métodos , Fosfatos/metabolismo , Administração Oral , Adulto , Ácido Aspártico/metabolismo , Colina/metabolismo , Creatina/metabolismo , Metabolismo Energético/fisiologia , Lobo Frontal/fisiologia , Humanos , Inositol/metabolismo , Masculino , Fosfocreatina/metabolismoRESUMO
The distinctive aftertaste associated with fish oil preparations used in clinical trials of omega-3 fatty acids may weaken the double-blind. This double-blind pilot study was designed to examine whether normal subjects could correctly 'guess' if they were receiving capsules containing concentrated fish oil or capsules of pure olive oil. The informed consent was designed to give subjects ambiguous expectations about what oil they might be receiving to examine whether this would influence their guess. Despite a marked difference in taste experience, there was no significant difference in correct guesses between the two groups. The results suggest that altering subjects' expectations could further improve the validity of the double-blind.