Increased density of GAD65/67 immunoreactive neurons in the posterior subiculum and parahippocampal gyrus in treated patients with chronic schizophrenia

Schreiber, Stefanie; Bernstein, Hans‐Gert; Fendrich, Robert; Stauch, Renate; Ketzler, Bianca; Dobrowolny, Henrik; Steiner, Johann; Schreiber, Frank; Bogerts, Bernhard

doi:10.3109/15622975.2010.539270

Cited by 16 publications

(8 citation statements)

References 48 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition to the decreased thalamus-FPCN coupling, we also observed abnormally increased connectivity between the thalamus and parahippocampal gyrus in patients during task performance. Structural changes in parahippocampal gyrus in patients with chronic schizophrenia have been previously reported (Schreiber et al, 2011). The current results therefore suggest that a shift from a normal thalamocortical (specifically, FPCN) coupling to an abnormal thalamolimbic coupling may contribute to WM differences between controls and patients.…”

Section: Thalamus-fpcn Disconnection In Schizophrenia During Task Persupporting

confidence: 71%

Disrupted Working Memory Circuitry in Schizophrenia: Disentangling fMRI Markers of Core Pathology vs Other Aspects of Impaired Performance

Eryilmaz

Tanner

et al. 2016

Neuropsychopharmacol

View full text Add to dashboard Cite

Working memory (WM) impairment, a core feature of schizophrenia, is often associated with aberrant dorsolateral prefrontal cortex (dlPFC) activation. Reduced resting-state connectivity within the frontoparietal control network (FPCN) has also been reported in schizophrenia. However, interpretation of WM-related dlPFC dysfunction has been limited by performance differences between patients and controls, and by uncertainty over the relevance of resting-state connectivity to network engagement during task. We contrasted brain activation in 40 schizophrenia patients and 40 controls during verbal WM performance, and evaluated underlying functional connectivity during rest and task. During correct trials, patients demonstrated normal FPCN activation, despite an inverse relationship between positive symptoms and activation. FPCN activation differed between the groups only during error trials (controls4patients). In contrast, controls demonstrated stronger deactivation of the ventromedial prefrontal cortex (vmPFC) during correct and error trials. Functional connectivity analysis indicated impaired resting-state FPCN connectivity in patients, but normal connectivity during task. However, patients showed abnormal connectivity among regions such as vmPFC, lateral orbitofrontal cortex, and parahippocampal gyrus (PHG) during both rest and task. During task, patients also exhibited altered thalamic connectivity to PHG and FPCN. Activation and connectivity patterns that were more characteristic of controls generally correlated with better performance. In summary, patients demonstrated normal FPCN activation when they remained on-task, and exhibited normal FPCN connectivity during WM, whereas vmPFC deactivation differences persisted regardless of WM performance. Our findings suggest that altered FPCN activation in patients reflects performance difference, and that limbic and thalamic dysfunction is critically involved in WM deficits in schizophrenia.

show abstract

Section: Thalamus-fpcn Disconnection In Schizophrenia During Task Persupporting

confidence: 71%

Disrupted Working Memory Circuitry in Schizophrenia: Disentangling fMRI Markers of Core Pathology vs Other Aspects of Impaired Performance

Eryilmaz

Tanner

et al. 2016

Neuropsychopharmacol

View full text Add to dashboard Cite

show abstract

“…1 Hypofunction of the GABAergic signaling system has been hypothesized to contribute to the pathologies of schizophrenia, bipolar disorder and major depressive disorder. 2, 3, 4, 5 Multiple laboratories have demonstrated a number of dysfunctions of the GABAergic signaling system in these disorders, including: (1) altered expression of glutamic acid decarboxylase 65 and 67 kDa proteins, 6, 7, 8 the enzymes that convert glutamate to GABA; (2) microarray results that have demonstrated increased mRNA for a number of GABA(A) (GABA A ) receptor subunits in prefrontal cortex (PFC) of subjects with schizophrenia; 9, 10, 11 and (3) gene association studies that link GABA receptor subunits to schizophrenia and mood disorders. 12, 13, 14 …”

Section: Introductionmentioning

confidence: 99%

Expression of GABAA α2-, β1- and ɛ-receptors are altered significantly in the lateral cerebellum of subjects with schizophrenia, major depression and bipolar disorder

Fatemi

Folsom

Rooney³

et al. 2013

Transl Psychiatry

105

View full text Add to dashboard Cite

There is abundant evidence that dysfunction of the γ-aminobutyric acid (GABA)ergic signaling system is implicated in the pathology of schizophrenia and mood disorders. Less is known about the alterations in protein expression of GABA receptor subunits in brains of subjects with schizophrenia and mood disorders. We have previously demonstrated reduced expression of GABAB receptor subunits 1 and 2 (GABBR1 and GABBR2) in the lateral cerebella of subjects with schizophrenia, bipolar disorder and major depressive disorder. In the current study, we have expanded these studies to examine the mRNA and protein expression of 12 GABAA subunit proteins (α1, α2, α3, α5, α6, β1, β2, β3, δ, ɛ, γ2 and γ3) in the lateral cerebella from the same set of subjects with schizophrenia (N=9–15), bipolar disorder (N=10–15) and major depression (N=12–15) versus healthy controls (N=10–15). We found significant group effects for protein levels of the α2-, β1- and ɛ-subunits across treatment groups. We also found a significant group effect for mRNA levels of the α1-subunit across treatment groups. New avenues for treatment, such as the use of neurosteroids to promote GABA modulation, could potentially ameliorate GABAergic dysfunction in these disorders.

show abstract

“…Conversely, Mishra et al (2010) reported positive findings for rTMS in reducing alcohol craving. Höppner et al (2011) showed mixed findings: although rTMS had no effect on alcohol craving, the authors found that real vs. sham rTMS increased the attentional blink on alcohol-related pictures.…”

Section: Resultsmentioning

confidence: 99%

A Systematic Review of Non-Invasive Brain Stimulation Therapies and Cardiovascular Risk: Implications for the Treatment of Major Depressive Disorder

Sampaio¹,

Fráguas²,

Lotufo³

et al. 2012

Front. Psychiatry

View full text Add to dashboard Cite

Major depressive disorder (MDD) and cardiovascular diseases are intimately associated. Depression is an independent risk factor for mortality in cardiovascular samples. Neuroendocrine dysfunctions in MDD are related to an overactive hypothalamus-pituitary-adrenal (HPA) axis and increased sympathetic activity. Novel intervention strategies for MDD include the non-invasive brain stimulation (NIBS) techniques such as repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS). In fact, although these techniques have being increasingly used as a treatment for MDD, their cardiovascular effects were not sufficiently investigated, which would be important considering the dyad MDD/cardiovascular disorders. We investigated this issue through a systematic review for published articles from the first date available to May 2012 in MEDLINE and other databases, looking for main risk factors and surrogate markers for cardiovascular disease such as: cortisol, heart rate variability (HRV), alcohol, smoking, obesity, hypertension, glucose. We identified 37 articles (981 subjects) according to our eligibility criteria. Our main findings were that NIBS techniques might be effective strategies for down-regulating HPA activity and regulating food, alcohol, and cigarette consumption. NIBS’s effects on HRV and blood pressure presented mixed findings, with studies suggesting that HRV values can decrease or remain unchanged after NIBS, while one study found that rTMS increased blood pressure levels. Also, a single study showed that glucose levels decrease after tDCS. However, most studies tested the acute effects after one single session of rTMS/tDCS; therefore further studies are necessary to investigate whether NIBS modifies cardiovascular risk factors in the long-term. In fact, considering the burden of cardiac disease, further trials in cardiovascular, depressed, and non-depressed samples using NIBS should be performed.

show abstract

Increased density of GAD65/67 immunoreactive neurons in the posterior subiculum and parahippocampal gyrus in treated patients with chronic schizophrenia

Abstract: The current data on GAD65/67 indicates a dysregulation of the GABAergic system in schizophrenia patients that may be associated with cognitive decline. However, a long term effect of neuroleptics on the GABAergic system cannot be excluded.

Cited by 16 publications

References 48 publications

Disrupted Working Memory Circuitry in Schizophrenia: Disentangling fMRI Markers of Core Pathology vs Other Aspects of Impaired Performance

Disrupted Working Memory Circuitry in Schizophrenia: Disentangling fMRI Markers of Core Pathology vs Other Aspects of Impaired Performance

Expression of GABAA α2-, β1- and ɛ-receptors are altered significantly in the lateral cerebellum of subjects with schizophrenia, major depression and bipolar disorder

A Systematic Review of Non-Invasive Brain Stimulation Therapies and Cardiovascular Risk: Implications for the Treatment of Major Depressive Disorder

Contact Info

Product

Resources

About