Real-Time Chemical Measurements of Dopamine Release in the Brain

Xanthurenic acid (XA) is a metabolite of the kynurenine pathway (KP) synthetized in the brain from dietary or microbial tryptophan that crosses the blood-brain barrier through carrier-mediated transport. XA and kynurenic acid (KYNA) are two structurally related compounds of KP occurring at micromolar concentrations in the CNS and suspected to modulate some pathophysiological mechanisms of neuropsychiatric and/or neurodegenerative diseases. Particularly, various data including XA cerebral distribution (from 1 µM in olfactory bulbs and cerebellum to 0.1–0.4 µM in A9 and A10), its release, and interactions with G protein-dependent XA-receptor, glutamate transporter and metabotropic receptors, strongly support a signaling and/or neuromodulatory role for XA. However, while the parent molecule KYNA is considered as potentially involved in neuropsychiatric disorders because of its inhibitory action on dopamine release in the striatum, the effect of XA on brain dopaminergic activity remains unknown. Here, we demonstrate that acute local/microdialysis-infusions of XA dose-dependently stimulate dopamine release in the rat prefrontal cortex (four-fold increase in the presence of 20 µM XA). This stimulatory effect is blocked by XA-receptor antagonist NCS-486. Interestingly, our results show that the peripheral/intraperitoneal administration of XA, which has been proven to enhance intra-cerebral XA concentrations (about 200% increase after 50 mg/kg XA i.p), also induces a dose-dependent increase of dopamine release in the cortex and striatum. Furthermore, our in vivo electrophysiological studies reveal that the repeated/daily administrations of XA reduce by 43% the number of spontaneously firing dopaminergic neurons in the ventral tegmental area. In the substantia nigra, XA treatment does not change the number of firing neurons. Altogether, our results suggest that XA may contribute together with KYNA to generate a KYNA/XA ratio that may crucially determine the brain normal dopaminergic activity. Imbalance of this ratio may result in dopaminergic dysfunctions related to several brain disorders, including psychotic diseases and drug dependence.

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Symposium Title: Training the Brain–Methodological Progress and Clinical Translation of Real-Time Neurofeedback Closed-Loop Modulation

International Journal of Psychophysiology ◽

10.1016/j.ijpsycho.2021.07.250 ◽

2021 ◽

Vol 168 ◽

pp. S81

Author(s):

Benjamin Becker

Keyword(s):

Real Time ◽

Closed Loop ◽

Clinical Translation ◽

The Brain

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Follow-up of intra-arterial delivery of bevacizumab for treatment of butterfly glioblastoma in patient with first-in-human, real-time MRI-guided intra-arterial neurointervention

Journal of NeuroInterventional Surgery ◽

10.1136/neurintsurg-2021-017900 ◽

2021 ◽

pp. neurintsurg-2021-017900

Author(s):

Michal Zawadzki ◽

Jerzy Walecki ◽

Boguslaw Kostkiewicz ◽

Kacper Kostyra ◽

Piotr Walczak ◽

...

Keyword(s):

Real Time ◽

Tumor Recurrence ◽

Tumor Volume ◽

Neurological Status ◽

Arterial Infusion ◽

Second Procedure ◽

Discharge From Hospital ◽

The Brain ◽

Positive Effect

This case report shows that real-time MRI may aid in the precision of intra-arterial delivery of bevacizumab to butterfly glioblastoma. Fast clinical improvement, decrease of contrast enhancing status, and no serious adverse effects were observed at discharge from hospital. The patient regained pre-recurrent neurological status for 2 months with a subsequent fast clinical decline and an increase in tumor volume. The patient underwent a second procedure of intra-arterial delivery of bevacizumab to the brain, with substantial clinical and radiological improvement, but not the level of improvement observed after the first procedure. Another clinical decline occurred with an increase in tumor size and the patient was treated 2 months later with a third intra-arterial infusion of bevacizumab. While another positive effect was achieved, it was less pronounced than before, and the patient died 1.5 months later. There were no technical, ischemic or other complications during the procedures. The patient survived 218 days from the first symptoms of tumor recurrence, 190 days from the first MRI, and 175 days from the first intra-arterial treatment of bevacizumab.

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Analyzing EEG of Quasi-Brain-Death Based on Dynamic Sample Entropy Measures

Computational and Mathematical Methods in Medicine ◽

10.1155/2013/618743 ◽

2013 ◽

Vol 2013 ◽

pp. 1-6 ◽

Cited By ~ 4

Author(s):

Li Ni ◽

Jianting Cao ◽

Rubin Wang

Keyword(s):

Brain Death ◽

Real Time ◽

Time Window ◽

Approximate Entropy ◽

Sample Entropy ◽

Well Performance ◽

Entropy Measures ◽

Brain Death Determination ◽

Death Determination ◽

The Brain

To give a more definite criterion using electroencephalograph (EEG) approach on brain death determination is vital for both reducing the risks and preventing medical misdiagnosis. This paper presents several novel adaptive computable entropy methods based on approximate entropy (ApEn) and sample entropy (SampEn) to monitor the varying symptoms of patients and to determine the brain death. The proposed method is a dynamic extension of the standard ApEn and SampEn by introducing a shifted time window. The main advantages of the developed dynamic approximate entropy (DApEn) and dynamic sample entropy (DSampEn) are for real-time computation and practical use. Results from the analysis of 35 patients (63 recordings) show that the proposed methods can illustrate effectiveness and well performance in evaluating the brain consciousness states.

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A review of flux considerations for in vivo neurochemical measurements

The Analyst ◽

10.1039/c4an01898b ◽

2015 ◽

Vol 140 (11) ◽

pp. 3709-3730 ◽

Cited By ~ 11

Author(s):

David W. Paul ◽

Julie A. Stenken

Keyword(s):

Mass Transport ◽

Data Interpretation ◽

Chemical Measurements ◽

The Brain

The mass transport of neurochemicals in the brain and how this flux affects chemical measurements and data interpretation is reviewed.

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NEUROECONOMICS, NEUROPHYSIOLOGY AND THE COMMON CURRENCY HYPOTHESIS

Economics and Philosophy ◽

10.1017/s0266267108002058 ◽

2008 ◽

Vol 24 (3) ◽

pp. 419-429 ◽

Cited By ~ 14

Author(s):

Anthony Landreth ◽

John Bickle

Keyword(s):

Rational Choice ◽

Dopamine Release ◽

Research Programme ◽

Neural Mechanism ◽

The Other ◽

Common Currency ◽

The Common ◽

The Brain ◽

Electrophysiological Methods

We briefly describe ways in which neuroeconomics has made contributions to its contributing disciplines, especially neuroscience, and a specific way in which it could make future contributions to both. The contributions of a scientific research programme can be categorized in terms of (1) description and classification of phenomena, (2) the discovery of causal relationships among those phenomena, and (3) the development of tools to facilitate (1) and (2). We consider ways in which neuroeconomics has advanced neuroscience and economics along each line. Then, focusing on electrophysiological methods, we consider a puzzle within neuroeconomics whose solution we believe could facilitate contributions to both neuroscience and economics, in line with category (2). This puzzle concerns how the brain assigns reward values to otherwise incomparable stimuli. According to the common currency hypothesis, dopamine release is a component of a neural mechanism that solves comparability problems. We review two versions of the common currency hypothesis, one proposed by Read Montague and colleagues, the other by William Newsome and colleagues, and fit these hypotheses into considerations of rational choice.

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Cloning, Characterization, and Expression Features of Chicken CDS2 Splicing Variants

10.21203/rs.3.rs-80587/v1 ◽

2020 ◽

Author(s):

Yuanyuan Xu ◽

Shuping Zhang ◽

Yujun Guo ◽

Wen Chen ◽

Yanqun Huang

Keyword(s):

Adipose Tissue ◽

Real Time ◽

Real Time Pcr ◽

Expression Patterns ◽

Mrna Levels ◽

Exogenous Insulin ◽

Quantitative Real Time Pcr ◽

Temporal Expression ◽

Spatio Temporal ◽

The Brain

Abstract Background: The CDS gene encodes the CDP-diacylglycerol synthase enzyme that catalyzes the formation of CDP-diacylglycerol (CDP-DAG) from phosphatidic acid. At present, there are no reports of CDS2 in birds. Here, we identified chicken CDS2 transcripts by combining conventional RT- PCR amplification, 5' RACE (Fig. 1A), and 3' RACE, explored the spatio-temporal expression profiles of total CDS2 and the longest transcript variant CDS2-4, and investigated the effect of exogenous insulin on total the mRNA level of CDS2 by quantitative real-time PCR. Results: Four transcripts of chicken CDS2 (CDS2-1, -2, -3, and -4) were identified, which were alternatively spliced at the 3′-untranslated region (UTR). CDS2 was widely expressed in all tissues examined and the longest variant CDS2-4 was the major transcript. Both total CDS2 and CDS2-4 were prominently expressed in adipose tissue and the heart, and exhibited low expression in the liver and pectoralis of 49 day-old chickens. Quantitative real-time PCR revealed that total CDS2 and CDS2-4 had different spatio-temporal expression patterns in chicken. Total CDS2 exhibited a similar temporal expression tendency with a high level in the later period of incubation (embryonic day 19 [E19] or 1-day-old) in the brain, liver, and pectoralis. While CDS2-4 presented a distinct temporal expression pattern in these tissues, CDS2-4 levels peaked at 21 days in the brain and pectoralis, while liver CDS2-4 mRNA levels were highest at the early stage of hatching (E10). Total CDS2 (P < 0.001) and CDS2-4 (P = 0.0090) mRNA levels in the liver were differentially regulated throughout development of the chicken. Exogenous insulin significantly downregulated the level of total CDS2 at 240 min in the pectoralis of Silky chickens (P < 0.01). Total CDS2 levels in the liver of Silky chickens were higher than that of the broiler in the basal state and after insulin stimulation. Conclusion: Chicken CDS2 has multiple transcripts with variation at the 3′-UTR, which was prominently expressed in adipose tissue. Total CDS2 and CDS2-4 presented distinct spatio-temporal expression patterns, and they were differentially regulated with age in liver. Insulin could regulate chicken CDS2 levels in a breed- and tissue-specific manner.

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