Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 38
Filtrar
1.
Hum Brain Mapp ; 45(1): e26553, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38224541

RESUMO

22q11.2 deletion syndrome (22q11DS) is the most frequently occurring microdeletion in humans. It is associated with a significant impact on brain structure, including prominent reductions in gray matter volume (GMV), and neuropsychiatric manifestations, including cognitive impairment and psychosis. It is unclear whether GMV alterations in 22q11DS occur according to distinct structural patterns. Then, 783 participants (470 with 22q11DS: 51% females, mean age [SD] 18.2 [9.2]; and 313 typically developing [TD] controls: 46% females, mean age 18.0 [8.6]) from 13 datasets were included in the present study. We segmented structural T1-weighted brain MRI scans and extracted GMV images, which were then utilized in a novel source-based morphometry (SBM) pipeline (SS-Detect) to generate structural brain patterns (SBPs) that capture co-varying GMV. We investigated the impact of the 22q11.2 deletion, deletion size, intelligence quotient, and psychosis on the SBPs. Seventeen GMV-SBPs were derived, which provided spatial patterns of GMV covariance associated with a quantitative metric (i.e., loading score) for analysis. Patterns of topographically widespread differences in GMV covariance, including the cerebellum, discriminated individuals with 22q11DS from healthy controls. The spatial extents of the SBPs that revealed disparities between individuals with 22q11DS and controls were consistent with the findings of the univariate voxel-based morphometry analysis. Larger deletion size was associated with significantly lower GMV in frontal and occipital SBPs; however, history of psychosis did not show a strong relationship with these covariance patterns. 22q11DS is associated with distinct structural abnormalities captured by topographical GMV covariance patterns that include the cerebellum. Findings indicate that structural anomalies in 22q11DS manifest in a nonrandom manner and in distinct covarying anatomical patterns, rather than a diffuse global process. These SBP abnormalities converge with previously reported cortical surface area abnormalities, suggesting disturbances of early neurodevelopment as the most likely underlying mechanism.


Assuntos
Síndrome de DiGeorge , Transtornos Psicóticos , Feminino , Humanos , Adolescente , Masculino , Síndrome de DiGeorge/diagnóstico por imagem , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Transtornos Psicóticos/complicações , Substância Cinzenta/diagnóstico por imagem
2.
Mol Psychiatry ; 26(7): 3350-3362, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33723417

RESUMO

The delayed behavioral response to chronic antidepressants depends on dynamic changes in the hippocampus. It was suggested that the antidepressant protein p11 and the chromatin remodeling factor SMARCA3 mediate this delayed response by inducing transcriptional changes in hippocampal neurons. However, what target genes are regulated by the p11/SMARCA3 complex to mediate the behavioral response to antidepressants, and what cell type mediates these molecular changes remain unknown. Here we report that the p11/SMARCA3 complex represses Neurensin-2 transcription in hippocampal parvalbumin-expressing interneurons after chronic treatment with Selective Serotonin Reuptake Inhibitors (SSRI). The behavioral response to antidepressants requires upregulation of p11, accumulation of SMARCA3 in the cell nucleus, and a consequent repression of Neurensin-2 transcription in these interneurons. We elucidate a functional role for p11/SMARCA3/Neurensin-2 pathway in regulating AMPA-receptor signaling in parvalbumin-expressing interneurons, a function that is enhanced by chronic treatment with SSRIs. These results link SSRIs to dynamic glutamatergic changes and implicate p11/SMARCA3/Neurensin-2 pathway in the development of more specific and efficient therapeutic strategies for neuropsychiatric disorders.


Assuntos
Antidepressivos , Proteínas de Ligação a DNA/metabolismo , Interneurônios/efeitos dos fármacos , Parvalbuminas , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Fatores de Transcrição/metabolismo , Animais , Antidepressivos/farmacologia , Hipocampo/metabolismo , Interneurônios/metabolismo , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos C57BL , Parvalbuminas/metabolismo
3.
Mol Psychiatry ; 25(6): 1191-1201, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-30804492

RESUMO

The behavioral response to antidepressants is closely associated with physiological changes in the function of neurons in the hippocampal dentate gyrus (DG). Parvalbumin interneurons are a major class of GABAergic neurons, essential for DG function, and are involved in the pathophysiology of several neuropsychiatric disorders. However, little is known about the role(s) of these neurons in major depressive disorder or in mediating the delayed behavioral response to antidepressants. Here we show, in mice, that hippocampal parvalbumin interneurons express functionally silent serotonin 5A receptors, which translocate to the cell membrane and become active upon chronic, but not acute, treatment with a selective serotonin reuptake inhibitor (SSRI). Activation of these serotonergic receptors in these neurons initiates a signaling cascade through which Gi-protein reduces cAMP levels and attenuates protein kinase A and protein phosphatase 2A activities. This results in increased phosphorylation and inhibition of Kv3.1ß channels, and thereby reduces the firing of the parvalbumin neurons. Through the loss of this signaling pathway in these neurons, conditional deletion of the serotonin 5A receptor leads to the loss of the physiological and behavioral responses to chronic antidepressants.


Assuntos
Antidepressivos/farmacologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Parvalbuminas/metabolismo , Receptores de Serotonina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Transtorno Depressivo Maior/tratamento farmacológico , Transtorno Depressivo Maior/metabolismo , Transtorno Depressivo Maior/patologia , Feminino , Hipocampo/citologia , Humanos , Interneurônios/efeitos dos fármacos , Interneurônios/metabolismo , Masculino , Camundongos
4.
Mol Psychiatry ; 25(11): 2818-2831, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-31358905

RESUMO

22q11.2 deletion syndrome (22q11DS)-a neurodevelopmental condition caused by a hemizygous deletion on chromosome 22-is associated with an elevated risk of psychosis and other developmental brain disorders. Prior single-site diffusion magnetic resonance imaging (dMRI) studies have reported altered white matter (WM) microstructure in 22q11DS, but small samples and variable methods have led to contradictory results. Here we present the largest study ever conducted of dMRI-derived measures of WM microstructure in 22q11DS (334 22q11.2 deletion carriers and 260 healthy age- and sex-matched controls; age range 6-52 years). Using harmonization protocols developed by the ENIGMA-DTI working group, we identified widespread reductions in mean, axial and radial diffusivities in 22q11DS, most pronounced in regions with major cortico-cortical and cortico-thalamic fibers: the corona radiata, corpus callosum, superior longitudinal fasciculus, posterior thalamic radiations, and sagittal stratum (Cohen's d's ranging from -0.9 to -1.3). Only the posterior limb of the internal capsule (IC), comprised primarily of corticofugal fibers, showed higher axial diffusivity in 22q11DS. 22q11DS patients showed higher mean fractional anisotropy (FA) in callosal and projection fibers (IC and corona radiata) relative to controls, but lower FA than controls in regions with predominantly association fibers. Psychotic illness in 22q11DS was associated with more substantial diffusivity reductions in multiple regions. Overall, these findings indicate large effects of the 22q11.2 deletion on WM microstructure, especially in major cortico-cortical connections. Taken together with findings from animal models, this pattern of abnormalities may reflect disrupted neurogenesis of projection neurons in outer cortical layers.


Assuntos
Síndrome de DiGeorge/diagnóstico por imagem , Síndrome de DiGeorge/patologia , Imagem de Difusão por Ressonância Magnética , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Adolescente , Adulto , Anisotropia , Criança , Síndrome de DiGeorge/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
5.
Mol Psychiatry ; 25(8): 1822-1834, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-29895892

RESUMO

The 22q11.2 deletion (22q11DS) is a common chromosomal microdeletion and a potent risk factor for psychotic illness. Prior studies reported widespread cortical changes in 22q11DS, but were generally underpowered to characterize neuroanatomic abnormalities associated with psychosis in 22q11DS, and/or neuroanatomic effects of variability in deletion size. To address these issues, we developed the ENIGMA (Enhancing Neuro Imaging Genetics Through Meta-Analysis) 22q11.2 Working Group, representing the largest analysis of brain structural alterations in 22q11DS to date. The imaging data were collected from 10 centers worldwide, including 474 subjects with 22q11DS (age = 18.2 ± 8.6; 46.9% female) and 315 typically developing, matched controls (age = 18.0 ± 9.2; 45.9% female). Compared to controls, 22q11DS individuals showed thicker cortical gray matter overall (left/right hemispheres: Cohen's d = 0.61/0.65), but focal thickness reduction in temporal and cingulate cortex. Cortical surface area (SA), however, showed pervasive reductions in 22q11DS (left/right hemispheres: d = -1.01/-1.02). 22q11DS cases vs. controls were classified with 93.8% accuracy based on these neuroanatomic patterns. Comparison of 22q11DS-psychosis to idiopathic schizophrenia (ENIGMA-Schizophrenia Working Group) revealed significant convergence of affected brain regions, particularly in fronto-temporal cortex. Finally, cortical SA was significantly greater in 22q11DS cases with smaller 1.5 Mb deletions, relative to those with typical 3 Mb deletions. We found a robust neuroanatomic signature of 22q11DS, and the first evidence that deletion size impacts brain structure. Psychotic illness in this highly penetrant deletion was associated with similar neuroanatomic abnormalities to idiopathic schizophrenia. These consistent cross-site findings highlight the homogeneity of this single genetic etiology, and support the suitability of 22q11DS as a biological model of schizophrenia.


Assuntos
Córtex Cerebral/patologia , Deleção Cromossômica , Síndrome de DiGeorge/genética , Síndrome de DiGeorge/patologia , Adolescente , Adulto , Feminino , Substância Cinzenta/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Transtornos Psicóticos/genética , Adulto Jovem
6.
J Neurosci ; 39(26): 5234-5242, 2019 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-31028115

RESUMO

Hypofunction of NMDA receptors has been considered a possible cause for the pathophysiology of schizophrenia. More recently, indirect ways to regulate NMDA that would be less disruptive have been proposed and metabotropic glutamate receptor subtype 5 (mGluR5) represents one such candidate. To characterize the cell populations involved, we demonstrated here that knock-out (KO) of mGluR5 in cholinergic, but not glutamatergic or parvalbumin (PV)-positive GABAergic, neurons reduced prepulse inhibition of the startle response (PPI) and enhanced sensitivity to MK801-induced locomotor activity. Inhibition of cholinergic neurons in the medial septum by DREADD (designer receptors exclusively activated by designer drugs) resulted in reduced PPI further demonstrating the importance of these neurons in sensorimotor gating. Volume imaging and quantification were used to compare PV and cholinergic cell distribution, density, and total cell counts in the different cell-type-specific KO lines. Electrophysiological studies showed reduced NMDA receptor-mediated currents in cholinergic neurons of the medial septum in mGluR5 KO mice. These results obtained from male and female mice indicate that cholinergic neurons in the medial septum represent a key cell type involved in sensorimotor gating and are relevant to pathologies associated with disrupted sensorimotor gating such as schizophrenia.SIGNIFICANCE STATEMENT The mechanistic complexity underlying psychiatric disorders remains a major challenge that is hindering the drug discovery process. Here, we generated genetically modified mouse lines to better characterize the involvement of the receptor mGluR5 in the fine-tuning of NMDA receptors, specifically in the context of sensorimotor gating. We evaluated the importance of knocking-out mGluR5 in three different cell types in two brain regions and performed different sets of experiments including behavioral testing and electrophysiological recordings. We demonstrated that cholinergic neurons in the medial septum represent a key cell-type involved in sensorimotor gating. We are proposing that pathologies associated with disrupted sensorimotor gating, such as with schizophrenia, could benefit from further evaluating strategies to modulate specifically cholinergic neurons in the medial septum.


Assuntos
Neurônios Colinérgicos/metabolismo , Atividade Motora/fisiologia , Receptor de Glutamato Metabotrópico 5/metabolismo , Filtro Sensorial/fisiologia , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Neurônios Colinérgicos/efeitos dos fármacos , Maleato de Dizocilpina/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Feminino , Masculino , Camundongos , Camundongos Knockout , Atividade Motora/efeitos dos fármacos , Técnicas de Patch-Clamp , Inibição Pré-Pulso/efeitos dos fármacos , Inibição Pré-Pulso/fisiologia , Receptor de Glutamato Metabotrópico 5/genética , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Reflexo de Sobressalto/efeitos dos fármacos , Reflexo de Sobressalto/fisiologia , Filtro Sensorial/efeitos dos fármacos
7.
J Neurosci ; 38(26): 5913-5924, 2018 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-29891732

RESUMO

A growing number of studies implicate the brain's reward circuitry in aggressive behavior. However, the cellular and molecular mechanisms within brain reward regions that modulate the intensity of aggression as well as motivation for it have been underexplored. Here, we investigate the cell-type-specific influence of ΔFosB, a transcription factor known to regulate a range of reward and motivated behaviors, acting in the nucleus accumbens (NAc), a key reward region, in male aggression in mice. We show that ΔFosB is specifically increased in dopamine D1 receptor (Drd1)-expressing medium spiny neurons (D1-MSNs) in NAc after repeated aggressive encounters. Viral-mediated induction of ΔFosB selectively in D1-MSNs of NAc intensifies aggressive behavior without affecting the preference for the aggression-paired context in a conditioned place preference (CPP) assay. In contrast, ΔFosB induction selectively in D2-MSNs reduces the time spent exploring the aggression-paired context during CPP without affecting the intensity of aggression per se. These data strongly support a dissociable cell-type-specific role for ΔFosB in the NAc in modulating aggression and aggression reward.SIGNIFICANCE STATEMENT Aggressive behavior is associated with several neuropsychiatric disorders and can be disruptive for affected individuals as well as their victims. Studies have shown a positive reinforcement mechanism underlying aggressive behavior that shares many common features with drug addiction. Here, we explore the cell-type-specific role of the addiction-associated transcription factor ΔFosB in the nucleus accumbens in aggression. We found that ΔFosB expression promotes aggressive behavior, effects that are dissociable from its effects on aggression reward. This finding is a significant first step in identifying therapeutic targets for the reduction of aggressive behavior across a range of neuropsychiatric illnesses.


Assuntos
Agressão/fisiologia , Núcleo Accumbens/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Animais , Comportamento Animal/fisiologia , Masculino , Camundongos , Camundongos Transgênicos , Neurônios/metabolismo , Recompensa
8.
J Med Internet Res ; 21(4): e11410, 2019 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-31025945

RESUMO

BACKGROUND: Online peer support forums require oversight to ensure they remain safe and therapeutic. As online communities grow, they place a greater burden on their human moderators, which increases the likelihood that people at risk may be overlooked. This study evaluated the potential for machine learning to assist online peer support by directing moderators' attention where it is most needed. OBJECTIVE: This study aimed to evaluate the accuracy of an automated triage system and the extent to which it influences moderator behavior. METHODS: A machine learning classifier was trained to prioritize forum messages as green, amber, red, or crisis depending on how urgently they require attention from a moderator. This was then launched as a set of widgets injected into a popular online peer support forum hosted by ReachOut.com, an Australian Web-based youth mental health service that aims to intervene early in the onset of mental health problems in young people. The accuracy of the system was evaluated using a holdout test set of manually prioritized messages. The impact on moderator behavior was measured as response ratio and response latency, that is, the proportion of messages that receive at least one reply from a moderator and how long it took for these replies to be made. These measures were compared across 3 periods: before launch, after an informal launch, and after a formal launch accompanied by training. RESULTS: The algorithm achieved 84% f-measure in identifying content that required a moderator response. Between prelaunch and post-training periods, response ratios increased by 0.9, 4.4, and 10.5 percentage points for messages labelled as crisis, red, and green, respectively, but decreased by 5.0 percentage points for amber messages. Logistic regression indicated that the triage system was a significant contributor to response ratios for green, amber, and red messages, but not for crisis messages. Response latency was significantly reduced (P<.001), between the same periods, by factors of 80%, 80%, 77%, and 12% for crisis, red, amber, and green messages, respectively. Regression analysis indicated that the triage system made a significant and unique contribution to reducing the time taken to respond to green, amber, and red messages, but not to crisis messages, after accounting for moderator and community activity. CONCLUSIONS: The triage system was generally accurate, and moderators were largely in agreement with how messages were prioritized. It had a modest effect on response ratios, primarily because moderators were already more likely to respond to high priority content before the introduction of triage. However, it significantly and substantially reduced the time taken for moderators to respond to prioritized content. Further evaluations are needed to assess the impact of mistakes made by the triage algorithm and how changes to moderator responsiveness impact the well-being of forum members.


Assuntos
Apoio Social , Triagem/métodos , Educação a Distância , Feminino , Humanos , Internet , Masculino
9.
J Med Internet Res ; 19(8): e267, 2017 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-28784594

RESUMO

BACKGROUND: Synchronous written conversations (or "chats") are becoming increasingly popular as Web-based mental health interventions. Therefore, it is of utmost importance to evaluate and summarize the quality of these interventions. OBJECTIVE: The aim of this study was to review the current evidence for the feasibility and effectiveness of online one-on-one mental health interventions that use text-based synchronous chat. METHODS: A systematic search was conducted of the databases relevant to this area of research (Medical Literature Analysis and Retrieval System Online [MEDLINE], PsycINFO, Central, Scopus, EMBASE, Web of Science, IEEE, and ACM). There were no specific selection criteria relating to the participant group. Studies were included if they reported interventions with individual text-based synchronous conversations (ie, chat or text messaging) and a psychological outcome measure. RESULTS: A total of 24 articles were included in this review. Interventions included a wide range of mental health targets (eg, anxiety, distress, depression, eating disorders, and addiction) and intervention design. Overall, compared with the waitlist (WL) condition, studies showed significant and sustained improvements in mental health outcomes following synchronous text-based intervention, and post treatment improvement equivalent but not superior to treatment as usual (TAU) (eg, face-to-face and telephone counseling). CONCLUSIONS: Feasibility studies indicate substantial innovation in this area of mental health intervention with studies utilizing trained volunteers and chatbot technologies to deliver interventions. While studies of efficacy show positive post-intervention gains, further research is needed to determine whether time requirements for this mode of intervention are feasible in clinical practice.


Assuntos
Saúde Mental/normas , Envio de Mensagens de Texto/estatística & dados numéricos , Estudos de Viabilidade , Humanos
10.
J Med Internet Res ; 18(9): e246, 2016 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-27619564

RESUMO

BACKGROUND: In the interests of patient health outcomes, it is important for medical students to develop clinical communication skills. We previously proposed a telehealth communication skills training platform (EQClinic) with automated nonverbal behavior feedback for medical students, and it was able to improve medical students' awareness of their nonverbal communication. OBJECTIVE: This study aimed to evaluate the effectiveness of EQClinic to improve clinical communication skills of medical students. METHODS: We conducted a 2-group randomized crossover trial between February and June 2016. Participants were second-year medical students enrolled in a clinical communication skills course at an Australian university. Students were randomly allocated to complete online EQClinic training during weeks 1-5 (group A) or to complete EQClinic training during weeks 8-11 (group B). EQClinic delivered an automated visual presentation of students' nonverbal behavior coupled with human feedback from a standardized patient (SP). All students were offered two opportunities to complete face-to-face consultations with SPs. The two face-to-face consultations were conducted in weeks 6-7 and 12-13 for both groups, and were rated by tutors who were blinded to group allocation. Student-Patient Observed Communication Assessment (SOCA) was collected by blinded assessors (n=28) at 2 time points and also by an SP (n=83). Tutor-rated clinical communications skill in face-to-face consultations was the primary outcome and was assessed with the SOCA. We used t tests to examine the students' performance during face-to-face consultations pre- and postexposure to EQClinic. RESULTS: We randomly allocated 268 medical students to the 2 groups (group A: n=133; group B: n=135). SOCA communication skills measures (score range 4-16) from the first face-to-face consultation were significantly higher for students in group A who had completed EQClinic training and reviewed the nonverbal behavior feedback, compared with group B, who had completed only the course curriculum components (P=.04). Furthermore, at the second face-to-face assessment, the group that completed a teleconsultation between the two face-to-face consultations (group B) showed improved communication skills (P=.005), and the one that had teleconsultations before the first face-to-face consultation (group A) did not show improvement. CONCLUSIONS: The EQClinic is a useful tool for medical students' clinical communication skills training that can be applied to university settings to improve students clinical communication skills development.


Assuntos
Competência Clínica , Comunicação , Educação de Graduação em Medicina/métodos , Feedback Formativo , Internet , Comunicação não Verbal , Simulação de Paciente , Austrália , Estudos Cross-Over , Currículo , Retroalimentação , Feminino , Humanos , Masculino , Encaminhamento e Consulta , Estudantes de Medicina , Telemedicina
11.
Qual Health Res ; 26(10): 1409-23, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-25896792

RESUMO

Although there is evidence of both clinical and personal recovery from distressing voices, the process of recovery over time is unclear. Narrative inquiry was used to investigate 11 voice-hearers' lived experience of recovery. After a period of despair/exhaustion, two recovery typologies emerged: (a) turning toward/empowerment, which involved developing a normalized account of voices, building voice-specific skills, integration of voices into daily life, and a transformation of identity, and (b) turning away/protective hibernation, which involved harnessing all available resources to survive the experience, with the importance of medication in recovery being emphasized. Results indicated the importance of services being sensitive and responsive to a person's recovery style at any given time and their readiness for change. Coming to hold a normalized account of voice-hearing and the self and witnessing of preferred narratives by others were essential in the more robust turning toward recovery typology.


Assuntos
Alucinações , Narração , Poder Psicológico , Humanos , Voz
12.
Infant Ment Health J ; 35(1): 21-32, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25424403

RESUMO

Mothers with borderline personality disorder (BPD) have disturbed relationships with their infants, possibly associated with poor nonverbal cue perception. Individuals with BPD are poor at recognizing emotion in adults and tend to misattribute neutral (i.e., no emotion) as sad. This study extends previous research by examining how mothers with BPD perceive known (own) and unknown (control) infant stimuli depicting happy, sad, and neutral emotions. The sample consisted of 13 women diagnosed with BPD and 13 healthy control mothers. All participants completed clinical and parenting questionnaires and an infant emotion recognition task. Compared to control mothers, mothers with BPD were significantly poorer at infant emotion recognition overall, but especially neutral expressions which were misattributed most often as sad. Performance was not related to disturbed parenting but rather mothers' age and illness duration. Neither the BPD nor control mothers showed enhanced accuracy for emotional displays of their own verses unknown infant-face images. Although the sample size was small, this study provides evidence that mothers with BPD negatively misinterpret neutral images, which may impact sensitive responding to infant emotional cues. These findings have implications for clinical practice and the development of remediation programs targeting emotion-perception disturbances in mothers with BPD.


Assuntos
Transtorno da Personalidade Borderline/psicologia , Expressão Facial , Mães/psicologia , Reconhecimento Visual de Modelos , Adolescente , Adulto , Maus-Tratos Infantis , Feminino , Humanos , Lactente , Relações Mãe-Filho , Escalas de Graduação Psiquiátrica , Testes Psicológicos , Fatores Socioeconômicos , Adulto Jovem
13.
Front Mol Neurosci ; 17: 1350716, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38828281

RESUMO

The prefrontal cortex (PFC) is a key neural node mediating behavioral responses to stress and the actions of ketamine, a fast-acting antidepressant. The molecular mechanisms underlying these processes, however, are not fully understood. Our recent study revealed a pivotal role of hippocampal Ahnak as a regulator of cellular and behavioral adaptations to chronic stress. However, despite its significant expression in the PFC, the contribution of cortical Ahnak to behavioral responses to stress and antidepressants remains unknown. Here, using a mouse model for chronic social stress, we find that Ahnak expression in the PFC is significantly increased in stress-resilient mice and positively correlated with social interaction after stress exposure. Conditional deletion of Ahnak in the PFC or forebrain glutamatergic neurons facilitates stress susceptibility, suggesting that Ahnak is required for behavioral resilience. Further supporting this notion, Ahnak expression in the PFC is increased after the administration of ketamine or its metabolite (2R, 6R)-hydroxynorketamine (HNK). Moreover, Ahnak deletion in forebrain glutamatergic neurons blocks the restorative behavioral effects of ketamine or HNK in stress-susceptible mice. This forebrain excitatory neuron-specific Ahnak deletion reduces the frequency of mini excitatory postsynaptic currents in layer II/III pyramidal neurons, suggesting that Ahnak may induce its behavioral effects via modulation of glutamatergic transmission in the PFC. Altogether, these data suggest that Ahnak in glutamatergic PFC neurons may be critical for behavioral resilience and antidepressant actions of ketamine or HNK in chronic social stress-exposed mice.

14.
Front Mol Neurosci ; 15: 898851, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35813065

RESUMO

Parvalbumin-expressing interneurons (PV neurons) maintain inhibitory control of local circuits implicated in behavioral responses to environmental stressors. However, the roles of molecular and cellular adaptations in PV neurons in stress susceptibility or resilience have not been clearly established. Here, we show behavioral outcomes of chronic social defeat stress (CSDS) are mediated by differential neuronal activity and gene expression in hippocampal PV neurons in mice. Using in vivo electrophysiology and chemogenetics, we find increased PV neuronal activity in the ventral dentate gyrus is required and sufficient for behavioral susceptibility to CSDS. PV neuron-selective translational profiling indicates mitochondrial oxidative phosphorylation is the most significantly altered pathway in stress-susceptible versus resilient mice. Among differentially expressed genes associated with stress-susceptibility and resilience, we find Ahnak, an endogenous regulator of L-type calcium channels which are implicated in the regulation of mitochondrial function and gene expression. Notably, Ahnak deletion in PV neurons impedes behavioral susceptibility to CSDS. Altogether, these findings indicate behavioral effects of chronic stress can be controlled by selective modulation of PV neuronal activity or a regulator of L-type calcium signaling in PV neurons.

15.
J Neurochem ; 117(2): 221-30, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21250998

RESUMO

The trigeminal ganglion is the largest of the cranial ganglia and responsible for transmitting sensory information for much of the face. The cell surface glycoprotein CD151 is an early marker of the trigeminal placode, the precursor to the ganglion. Here, we investigate the role of CD151 during specification of trigeminal placode cells in the developing chicken embryo. Expression of the transcription factor Pax3, the earliest known marker of the trigeminal placode, briefly precedes that of CD151, but they then subsequently overlap in the trigeminal placode. Loss of CD151 protein dramatically decreases the number of Pax3+ placode cells in Stage 13-14 embryos, leading to loss of ophthalmic trigeminal neurons by Stages 16 and 17. Although the initial size of the Pax3 population is similar to that in controls, the number of Pax3+ cells decreases with time without alterations in cell death or proliferation. This suggests a role for CD151 in maintenance of the specification state in the trigeminal placode, uncovering the first known role for a tetraspanin in a developmental system.


Assuntos
Antígenos CD/metabolismo , Padronização Corporal/fisiologia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Gânglio Trigeminal/metabolismo , Análise de Variância , Animais , Antígenos CD/química , Padronização Corporal/efeitos dos fármacos , Contagem de Células/métodos , Proliferação de Células/efeitos dos fármacos , Embrião de Galinha , Ectoderma/embriologia , Eletroporação/métodos , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Oligodesoxirribonucleotídeos Antissenso/farmacologia , Fatores de Transcrição Box Pareados/metabolismo , Tetraspanina 24 , Gânglio Trigeminal/efeitos dos fármacos , Gânglio Trigeminal/embriologia
16.
Cancer Immunol Immunother ; 60(7): 975-84, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21461842

RESUMO

MUC1 (CA15-3) and MUC16 (CA125) tumor-associated antigens are upregulated in ovarian cancer and can be detected in patients' sera by standardized tests. We postulated that increased MUC1 and MUC16 antigens augment antibody responses in platinum-resistant ovarian cancer patients and that the frequency and intensity of these responses can be used as immune biomarkers of treatment response and disease outcome. We measured MUC1 and MUC16 tumor expression by immunohistochemistry (IHC), assessed serum antigenic levels and quantitated circulating antibodies by ELISA in a cohort of 28 ovarian cancer patients with platinum-resistant or platinum-refractory ovarian cancer, and treated with intraperitoneal (IP) interleukin-2 (IL-2). MUC1 and MUC16 were overexpressed in tumor samples and showed differential distribution profiles. Serum MUC1 (CA15-3) measurements were elevated in all patients and significantly correlated with increased risk of death (P = 0.003). MUC1-specific IgM and IgG anitbodies were found in 92 and 50% of cases, respectively. Patients with progressive disease had higher mean anti-MUC1 IgG than responders at both early (P = 0.025) and late (P = 0.022) time points during IP IL-2 treatment. Anti-MUC1 IgM antibodies inversely correlated with overall survival at both early (P = 0.052) and late (P = 0.009) time points. In contrast to MUC1, neither soluble MUC16 nor MUC16-specific antibodies were significantly associated with clinical response or overall survival in this study. Increased serum MUC1 and high anti-MUC1 antibody levels are prognostic for poor clinical response and reduced overall survival in platinum-resistant or platinum-refractory ovarian cancer.


Assuntos
Anticorpos Antineoplásicos/sangue , Autoanticorpos/sangue , Biomarcadores Tumorais/imunologia , Antígeno Ca-125/imunologia , Resistencia a Medicamentos Antineoplásicos , Proteínas de Membrana/imunologia , Mucina-1/imunologia , Neoplasias Ovarianas/imunologia , Adenocarcinoma de Células Claras/tratamento farmacológico , Adenocarcinoma de Células Claras/imunologia , Estudos de Casos e Controles , Cistadenocarcinoma Seroso/tratamento farmacológico , Cistadenocarcinoma Seroso/imunologia , Neoplasias do Endométrio/tratamento farmacológico , Neoplasias do Endométrio/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Técnicas Imunoenzimáticas , Injeções Intraperitoneais , Interleucina-2/uso terapêutico , Compostos Organoplatínicos/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico , Prognóstico
17.
Psychiatry Res ; 189(2): 292-8, 2011 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-21831452

RESUMO

People with 22q11.2 deletion syndrome (22q11DS) have deficits in face emotion recognition. However, it is not known whether this is a deficit specific to faces, or represents maladaptive information processing strategies to complex stimuli in general. This study examined the specificity of face emotion processing deficits in 22q11DS by exploring recognition accuracy and visual scanpath performance to a Faces task compared to a Weather Scene task. Seventeen adolescents with 22q11DS (11=females, age=17.4) and 18 healthy controls (11=females, age=17.7) participated in the study. People with 22q11DS displayed an overall impoverished scanning strategy to face and weather stimuli alike, resulting in poorer accuracy across all stimuli for the 22q11DS participants compared to controls. While the control subjects altered their information processing in response to faces, a similar change was not present in the 22q11DS group indicating different visual scanpath strategies to identify category within each of the tasks, of which faces appear to represent a particularly difficult subcategory. To conclude, while this study indicates that people with 22q11DS have a general visual processing deficit, the lack of strategic change between tasks suggest that the 22q11DS group did not adapt to the change in stimuli content as well as the controls, indicative of cognitive inflexibility rather than a face specific deficit.


Assuntos
Síndrome de DiGeorge/complicações , Emoções/fisiologia , Expressão Facial , Reconhecimento Visual de Modelos/fisiologia , Prosopagnosia/etiologia , Adolescente , Criança , Movimentos Oculares/fisiologia , Feminino , Humanos , Inteligência/fisiologia , Masculino , Estimulação Luminosa , Tempo de Reação , Percepção Espacial/fisiologia , Adulto Jovem
18.
Dev Biol ; 332(2): 189-95, 2009 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-19500565

RESUMO

Whereas neural crest cells are the source of the peripheral nervous system in the trunk of vertebrates, the "ectodermal placodes," together with neural crest, form the peripheral nervous system of the head. Cranial ectodermal placodes are thickenings in the ectoderm that subsequently ingress or invaginate to make important contributions to cranial ganglia, including epibranchial and trigeminal ganglia, and sensory structures, the ear, nose, lens, and adenohypophysis. Recent studies have uncovered a number of molecular signals mediating induction and differentiation of placodal cells. Here, we described recent advances in understanding the tissue interactions and signals underlying induction and neurogenesis of placodes, with emphasis on the trigeminal and epibranchial. Important roles of Fibroblast Growth Factors, Platelet Derived Growth Factors, Sonic Hedgehog, TGFbeta superfamily members, and Wnts are discussed.


Assuntos
Ectoderma/fisiologia , Cabeça , Morfogênese/fisiologia , Crista Neural/fisiologia , Animais , Indução Embrionária/fisiologia , Cabeça/anatomia & histologia , Cabeça/embriologia , Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , Crista Neural/citologia , Neurogênese , Transdução de Sinais/fisiologia
19.
Psychiatry Res ; 177(1-2): 211-5, 2010 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-20381171

RESUMO

Previous research demonstrates that people with 22q11.2 deletion syndrome (22q11DS) have social and interpersonal skill deficits. However, the basis of this deficit is unknown. This study examined, for the first time, how people with 22q11DS process emotional face stimuli using visual scanpath technology. The visual scanpaths of 17 adolescents and age/gender matched healthy controls were recorded while they viewed face images depicting one of seven basic emotions (happy, sad, surprised, angry, fear, disgust and neutral). Recognition accuracy was measured concurrently. People with 22q11DS differed significantly from controls, displaying visual scanpath patterns that were characterised by fewer fixations and a shorter scanpath length. The 22q11DS group also spent significantly more time gazing at the mouth region and significantly less time looking at eye regions of the faces. Recognition accuracy was correspondingly impaired, with 22q11DS subjects displaying particular deficits for fear and disgust. These findings suggest that 22q11DS is associated with a maladaptive visual information processing strategy that may underlie affect recognition accuracy and social functioning deficits in this group.


Assuntos
Atenção/fisiologia , Aberrações Cromossômicas , Deleção Cromossômica , Cromossomos Humanos Par 22 , Expressão Facial , Adolescente , Olho , Feminino , Humanos , Masculino , Boca , Testes Neuropsicológicos , Reconhecimento Visual de Modelos , Estimulação Luminosa , Adulto Jovem
20.
Aust N Z J Psychiatry ; 44(11): 1029-35, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21034186

RESUMO

OBJECTIVE: This article describes the establishment of the Australian Schizophrenia Research Bank (ASRB), which operates to collect, store and distribute linked clinical, cognitive, neuroimaging and genetic data from a large sample of people with schizophrenia and healthy controls. METHOD: Recruitment sources for the schizophrenia sample include a multi-media national advertising campaign, inpatient and community treatment services and non-government support agencies. Healthy controls have been recruited primarily through multi-media advertisements. All participants undergo an extensive diagnostic and family history assessment, neuropsychological evaluation, and blood sample donation for genetic studies. Selected individuals also complete structural MRI scans. RESULTS: Preliminary analyses of 493 schizophrenia cases and 293 healthy controls are reported. Mean age was 39.54 years (SD = 11.1) for the schizophrenia participants and 37.38 years (SD = 13.12) for healthy controls. Compared to the controls, features of the schizophrenia sample included a higher proportion of males (cases 65.9%; controls 46.8%), fewer living in married or de facto relationships (cases 16.1%; controls 53.6%) and fewer years of education (cases 13.05, SD = 2.84; controls 15.14, SD = 3.13), as well as lower current IQ (cases 102.68, SD = 15.51; controls 118.28, SD = 10.18). These and other sample characteristics are compared to those reported in another large Australian sample (i.e. the Low Prevalence Disorders Study), revealing some differences that reflect the different sampling methods of these two studies. CONCLUSION: The ASRB is a valuable and accessible schizophrenia research facility for use by approved scientific investigators. As recruitment continues, the approach to sampling for both cases and controls will need to be modified to ensure that the ASRB samples are as broadly representative as possible of all cases of schizophrenia and healthy controls.


Assuntos
Bases de Dados Factuais , Esquizofrenia/epidemiologia , Adolescente , Adulto , Idoso , Austrália/epidemiologia , Encéfalo/diagnóstico por imagem , Bases de Dados Factuais/estatística & dados numéricos , Feminino , Humanos , Masculino , Estado Civil , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Radiografia , Esquizofrenia/sangue , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/etiologia , Esquizofrenia/genética , Psicologia do Esquizofrênico , Fatores Socioeconômicos , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA