Background And Purpose: This study aims to investigate the longitudinal changes in translocator protein (TSPO) following stroke in different brain regions and potential associations with chronic brain infarction.
Methods: Twelve patients underwent SPECT using the TSPO tracer 6-Chloro-2-(4'-123I-Iodophenyl)-3-(N,N-Diethyl)-Imidazo[1,2-a]Pyridine-3-Acetamide, as well as structural MRI, at 10, 41, and 128 days (median) after ischemic infarction in the middle cerebral artery. TSPO expression was measured in lesional (MRI lesion and SPECT lesion), connected (pons and ipsilesional thalamus), and nonconnected (ipsilesional cerebellum and contralesional occipital cortex) regions.
Individuals with bipolar disorder (BD) show heterogeneity in clinical, cognitive, and daily functioning characteristics, which challenges accurate diagnostics and optimal treatment. A key goal is to identify brain-based biomarkers that inform patient stratification and serve as treatment targets. The objective of the present study was to apply a data-driven, multivariate approach to quantify the relationship between multimodal imaging features and behavioral phenotypes in BD.
View Article and Find Full Text PDFIntroduction: Alcohol use disorder (AUD) is a massive burden for the individual, relatives and society. Despite this, the treatment gap is wide compared with other mental health disorders. Treatment options are sparse, with only three Food and Drug Administration (FDA)-approved pharmacotherapies.
View Article and Find Full Text PDFBackground: Using [F]altanserin, a serotonin 2A receptor (5-HTR) antagonist Positron Emission Tomography (PET) tracer, a positive association between cortical 5-HTR binding and the inward-directed facets of neuroticism has been demonstrated in healthy individuals. Psilocybin, a 5-HTR agonist, shows promise for the treatment of depression, reducing neuroticism and mood symptoms potentially via hypothalamic-pituitary-adrenal (HPA) modulation. 5-HTR and neuroticism are both modulated by HPA axis function.
View Article and Find Full Text PDFProg Neuropsychopharmacol Biol Psychiatry
October 2024
Selective serotonin reuptake inhibitors (SSRI) are frequently ineffective in treating depressive episodes and biomarkers are needed to optimize antidepressant treatment outcomes. DNA methylation levels of serotonin transporter (SLC6A4) and tryptophan hydroxylase 2 genes (TPH2) have been suggested to predict antidepressant clinical outcomes but their applicability remains uncertain. In this study, we: 1) evaluated SLC6A4/TPH2 methylation biomarker potential for predicting clinical outcomes after escitalopram treatment; 2) evaluated whether changes in SLC6A4/TPH2 methylation are informative of treatment mechanisms.
View Article and Find Full Text PDFTrials
October 2024
Depression is a multifactorial clinical syndrome with a low pharmacological treatment response rate. Therefore, identifying predictors of treatment response capable of providing the basis for future developments of individualized therapies is crucial. Here, we applied model-free and model-based measures of whole-brain turbulent dynamics in resting-state functional magnetic resonance imaging (fMRI) in healthy controls and unmedicated depressed patients.
View Article and Find Full Text PDFBackground: Brain serotonin 4 receptor (5-HTR) levels are lower in untreated patients with major depressive disorder (MDD) and are linked to verbal memory. Here, we investigated the relationship between 5-HTR levels, clinical outcomes, and cognitive function in patients with MDD who initiated selective serotonin reuptake inhibitor drug treatment.
Methods: Ninety patients with moderate to severe depression underwent molecular brain imaging to measure 5-HTR binding prior to antidepressant treatment with escitalopram.
Major depressive disorder (MDD) is a highly prevalent psychiatric disorder and a leading cause of disability worldwide. Brain-derived neurotrophic factor (BDNF), a signaling protein responsible for promoting neuroplasticity, is highly expressed in the central nervous system but can also be found in the blood. Since impaired brain plasticity is considered a cornerstone in the pathophysiology of MDD, measurement of BDNF in blood has been proposed as a potential biomarker in MDD.
View Article and Find Full Text PDFSurvival rates after out-of-hospital cardiac arrest have improved over the past two decades. Despite this progress, long-term cognitive impairment remains prevalent even in those with early recovery of consciousness after out-of-hospital cardiac arrest; however, little is known about the determinants and underlying mechanisms. We utilized the REcovery after cardiac arrest surVIVAL cohort of out-of-hospital cardiac arrest survivors who fully regained consciousness to correlate cognition measurements with brain network changes using resting-state functional MRI and the Montreal Cognitive Assessment at hospital discharge and a comprehensive neuropsychological assessment at three-month follow-up.
View Article and Find Full Text PDFSynapses are fundamental to the function of the central nervous system and are implicated in a number of brain disorders. Despite their pivotal role, a comprehensive imaging resource detailing the distribution of synapses in the human brain has been lacking until now. Here, we employ high-resolution PET neuroimaging in healthy humans (17F/16M) to create a 3D atlas of the synaptic marker Synaptic Vesicle glycoprotein 2A (SV2A).
View Article and Find Full Text PDFThe postsynaptic density (PSD) comprises numerous scaffolding proteins, receptors, and signaling molecules that coordinate synaptic transmission in the brain. Postsynaptic density protein 95 (PSD-95) is a master scaffold protein within the PSD and one of its most abundant proteins and therefore constitutes a very attractive biomarker of PSD function and its pathological changes. Here, we exploit a high-affinity inhibitor of PSD-95, AVLX-144, as a template for developing probes for molecular imaging of the PSD.
View Article and Find Full Text PDFMajor depressive disorder (MDD) is a heterogeneous clinical syndrome with widespread subtle neuroanatomical correlates. Our objective was to identify the neuroanatomical dimensions that characterize MDD and predict treatment response to selective serotonin reuptake inhibitor (SSRI) antidepressants or placebo. In the COORDINATE-MDD consortium, raw MRI data were shared from international samples ( = 1,384) of medication-free individuals with first-episode and recurrent MDD ( = 685) in a current depressive episode of at least moderate severity, but not treatment-resistant depression, as well as healthy controls ( = 699).
View Article and Find Full Text PDFBackground: To investigate patients with disorders of consciousness (DoC) for residual awareness, guidelines recommend quantifying glucose brain metabolism using positron emission tomography. However, this is not feasible in the intensive care unit (ICU). Cerebral blood flow (CBF) assessed by arterial spin labeling magnetic resonance imaging (ASL-MRI) could serve as a proxy for brain metabolism and reflect consciousness levels in acute DoC.
View Article and Find Full Text PDFEur Neuropsychopharmacol
August 2024
Background: Rumination is a maladaptive response to distress characteristic of Major Depressive Disorder (MDD). It is unclear to what degree rumination is associated with depression severity prior to treatment and how it responds to antidepressant treatment. Therefore, we evaluated the association between rumination and depression severity in 92 untreated patients with MDD and explored the changes in rumination after initiation of antidepressant medication.
View Article and Find Full Text PDFBackground: Methylation of serotonin-related genes has been proposed as a plausible gene-by-environment link which may mediate environmental stress, depressive and anxiety symptoms. DNA methylation is often measured in blood cells, but little is known about the association between this peripheral epigenetic modification and brain serotonergic architecture. Here, we evaluated the association between whole-blood-derived methylation of four CpG sites in the serotonin transporter (SLC6A4) and six CpG sites of the tryptophan hydroxylase 2 (TPH2) gene and in-vivo brain levels of serotonin transporter (5-HTT) and serotonin 4 receptor (5-HT) in a cohort of healthy individuals (N = 254) and, for 5-HT in a cohort of unmedicated patients with depression (N = 90).
View Article and Find Full Text PDFEur J Nucl Med Mol Imaging
September 2024
Objectives: This study aimed to investigate the neural underpinnings of emotional cognition subgroups in recently diagnosed patients with bipolar disorder (BD) and change over time over a 15-month follow-up period.
Methods: Patients and healthy controls (HC) underwent emotional and nonemotional cognitive assessments and functional magnetic resonance imaging (fMRI) at the baseline (BD n = 87; HC n = 65) and at 15-month follow-up (BD n = 44; HC n = 38). Neural activity during emotion reactivity and regulation in response to aversive pictures was assessed during fMRI.
The glymphatic system is centred around brain cerebrospinal fluid flow and is enhanced during sleep, and the synaptic homeostasis hypothesis proposes that sleep acts on brain microstructure by selective synaptic downscaling. While so far primarily studied in animals, we here examine in humans if brain diffusivity and microstructure is related to time of day, sleep quality and cognitive performance. We use diffusion weighted images from 916 young healthy individuals, aged between 22 and 37 years, collected as part of the Human Connectome Project to assess diffusion tensor image analysis along the perivascular space index, white matter fractional anisotropy, intra-neurite volume fraction and extra-neurite mean diffusivity.
View Article and Find Full Text PDFTo better assess the pathology of neurodegenerative disorders and the efficacy of neuroprotective interventions, it is necessary to develop biomarkers that can accurately capture age-related biological changes in the human brain. Brain serotonin 2A receptors (5-HT2AR) show a particularly profound age-related decline and are also reduced in neurodegenerative disorders, such as Alzheimer's disease. This study investigates whether the decline in 5-HT2AR binding, measured in vivo using positron emission tomography (PET), can be used as a biomarker for brain aging.
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