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Bogdan Galusca - One of the best experts on this subject based on the ideXlab platform.
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1895 – Cerebral opioid activity in patients with restricting-type anorexia nervosa before and after weight recovery: a [11c]Diprenorphine pet study
European Psychiatry, 2013Co-Authors: J. Soranzo, Nicolas Costes, N. Germain-zito, D. Le Bars, S. Billard, François Lang, Bruno Estour, Bogdan GaluscaAbstract:Introduction Opioid peripheral abnormalities were described in anorexia nervosa (AN). Until now no data have been published on cerebral activity of opioid system in these subjects. Diprenorphine is a ligand with non-specific binding to opiates receptors μ, κ and δ. Aim To evaluate in vivo brain opioid receptors binding potential (BP) in patients with lean and recovered from restrictive-type AN by comparison with controls and the relationship with eating-related psychochological and hormonal traits. Methods In 17 lean restrictive-type AN patients, 15 recovered AN subjects and 15 age-matched controls we assessed in vivo [ 11 C]Diprenorphine binding by brain positron emission tomography and eating-related psychopathological traits. Inter-groups differences in [ 11 C]Diprenorphine binding were evaluated by voxel-based analyses. Results Lean restrictive AN and recovered AN patients presented with similar decreased [ 11 C]Diprenorphine binding in bilateral medial frontal cortex and temporo-parietal cortex. We noted a lower BP in hypothalamo-pituitary structures and also in anterior cingulate gyrus in lean AN patients. Additionally, only recovered AN patients presented with a decreased [ 11 C]Diprenorphine binding in caudate nuclei and putamen. Direct correlations were found between the anterior cingulate gyrus BP and mean cortisol and between the left amygdala [ 11 C]Diprenorphine binding and eating concern score. Conclusion The opioid system is widely affected in AN even after recovery in regions known to be involved in the neurocircuitry of addiction and support the hypothesis of an organic dysfunction in AN.
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1895 cerebral opioid activity in patients with restricting type anorexia nervosa before and after weight recovery a 11c Diprenorphine pet study
European Psychiatry, 2013Co-Authors: J. Soranzo, Nicolas Costes, S. Billard, François Lang, Bruno Estour, N Germainzito, Le D Bars, Bogdan GaluscaAbstract:Introduction Opioid peripheral abnormalities were described in anorexia nervosa (AN). Until now no data have been published on cerebral activity of opioid system in these subjects. Diprenorphine is a ligand with non-specific binding to opiates receptors μ, κ and δ. Aim To evaluate in vivo brain opioid receptors binding potential (BP) in patients with lean and recovered from restrictive-type AN by comparison with controls and the relationship with eating-related psychochological and hormonal traits. Methods In 17 lean restrictive-type AN patients, 15 recovered AN subjects and 15 age-matched controls we assessed in vivo [ 11 C]Diprenorphine binding by brain positron emission tomography and eating-related psychopathological traits. Inter-groups differences in [ 11 C]Diprenorphine binding were evaluated by voxel-based analyses. Results Lean restrictive AN and recovered AN patients presented with similar decreased [ 11 C]Diprenorphine binding in bilateral medial frontal cortex and temporo-parietal cortex. We noted a lower BP in hypothalamo-pituitary structures and also in anterior cingulate gyrus in lean AN patients. Additionally, only recovered AN patients presented with a decreased [ 11 C]Diprenorphine binding in caudate nuclei and putamen. Direct correlations were found between the anterior cingulate gyrus BP and mean cortisol and between the left amygdala [ 11 C]Diprenorphine binding and eating concern score. Conclusion The opioid system is widely affected in AN even after recovery in regions known to be involved in the neurocircuitry of addiction and support the hypothesis of an organic dysfunction in AN.
Anthony K. P. Jones - One of the best experts on this subject based on the ideXlab platform.
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A highly reproducible method for the measurement of [6-O-methyl-11 C]Diprenorphine and its radio-metabolites based on solid-phase extraction and radio-high-pressure liquid chromatography.
Journal of labelled compounds & radiopharmaceuticals, 2020Co-Authors: Michael Fairclough, Adam Mcmahon, Elizabeth Barnett, Julian C. Matthews, Christopher A. Brown, Anthony K. P. JonesAbstract:Described here is a method for the measurement of the radio-metabolites of the positron emission tomography radiotracer [6-O-methyl-11 C]Diprenorphine ([11 C]Diprenorphine) using in-line solid-phase extraction (SPE) combined with radio-high-pressure liquid chromatography analysis. We believe that this method offers a reliable and reproducible approach to [11 C]Diprenorphine metabolite analysis. In addition, different SPE stationary phases are assessed for their efficiency for loading, retention and elution of the parent molecule and its metabolites. Having assessed C4, phenyl and C18 stationary phase, we concluded that a C18 SPE was optimal for our method. Finally, in silico predictions of Diprenorphine metabolism were compared with in vivo metabolism of [11 C]Diprenorphine induced by hepatic microsomal digestion and analysed by matrix-assisted laser desorption/ionisation mass spectrometry. It was found that there was a high degree of agreement between the two methods and in particular the formation of the Diprenorphine-3-glucuronide metabolite.
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the automated radiosynthesis and purification of the opioid receptor antagonist 6 o methyl 11c Diprenorphine on the ge tracerlab fxfe radiochemistry module
Journal of Labelled Compounds and Radiopharmaceuticals, 2014Co-Authors: Michael Fairclough, Christian Prenant, Gavin Brown, Adam Mcmahon, Jonathan Lowe, Anthony K. P. JonesAbstract:[6-O-Methyl-(11)C]Diprenorphine ([(11)C]Diprenorphine) is a positron emission tomography ligand used to probe the endogenous opioid system in vivo. Diprenorphine acts as an antagonist at all of the opioid receptor subtypes, that is, μ (mu), κ (kappa) and δ (delta). The radiosynthesis of [(11)C]Diprenorphine using [(11)C]methyl iodide produced via the 'wet' method on a home-built automated radiosynthesis set-up has been described previously. Here, we describe a modified synthetic method to [(11)C]Diprenorphine performed using [(11)C]methyl iodide produced via the gas phase method on a GE TRACERlab FXFE radiochemistry module. Also described is the use of [(11)C]methyl triflate as the carbon-11 methylating agent for the [(11)C]Diprenorphine syntheses. [(11)C]Diprenorphine was produced to good manufacturing practice standards for use in a clinical setting. In comparison to previously reported [(11)C]Diprenorphine radiosyntheisis, the method described herein gives a higher specific activity product which is advantageous for receptor occupancy studies. The radiochemical purity of [(11)C]Diprenorphine is similar to what has been reported previously, although the radiochemical yield produced in the method described herein is reduced, an issue that is inherent in the gas phase radiosynthesis of [(11)C]methyl iodide. The yields of [(11)C]Diprenorphine are nonetheless sufficient for clinical research applications. Other advantages of the method described herein are an improvement to both reproducibility and reliability of the production as well as simplification of the purification and formulation steps. We suggest that our automated radiochemistry route to [(11)C]Diprenorphine should be the method of choice for routine [(11)C]Diprenorphine productions for positron emission tomography studies, and the production process could easily be transferred to other radiochemistry modules such as the TRACERlab FX C pro.
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The automated radiosynthesis and purification of the opioid receptor antagonist, [6‐O‐methyl‐11C]Diprenorphine on the GE TRACERlab FXFE radiochemistry module
Journal of labelled compounds & radiopharmaceuticals, 2014Co-Authors: Michael Fairclough, Christian Prenant, Gavin Brown, Adam Mcmahon, Jonathan Lowe, Anthony K. P. JonesAbstract:[6-O-Methyl-(11)C]Diprenorphine ([(11)C]Diprenorphine) is a positron emission tomography ligand used to probe the endogenous opioid system in vivo. Diprenorphine acts as an antagonist at all of the opioid receptor subtypes, that is, μ (mu), κ (kappa) and δ (delta). The radiosynthesis of [(11)C]Diprenorphine using [(11)C]methyl iodide produced via the 'wet' method on a home-built automated radiosynthesis set-up has been described previously. Here, we describe a modified synthetic method to [(11)C]Diprenorphine performed using [(11)C]methyl iodide produced via the gas phase method on a GE TRACERlab FXFE radiochemistry module. Also described is the use of [(11)C]methyl triflate as the carbon-11 methylating agent for the [(11)C]Diprenorphine syntheses. [(11)C]Diprenorphine was produced to good manufacturing practice standards for use in a clinical setting. In comparison to previously reported [(11)C]Diprenorphine radiosyntheisis, the method described herein gives a higher specific activity product which is advantageous for receptor occupancy studies. The radiochemical purity of [(11)C]Diprenorphine is similar to what has been reported previously, although the radiochemical yield produced in the method described herein is reduced, an issue that is inherent in the gas phase radiosynthesis of [(11)C]methyl iodide. The yields of [(11)C]Diprenorphine are nonetheless sufficient for clinical research applications. Other advantages of the method described herein are an improvement to both reproducibility and reliability of the production as well as simplification of the purification and formulation steps. We suggest that our automated radiochemistry route to [(11)C]Diprenorphine should be the method of choice for routine [(11)C]Diprenorphine productions for positron emission tomography studies, and the production process could easily be transferred to other radiochemistry modules such as the TRACERlab FX C pro.
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Measurement of changes in opioid receptor binding in vivo during trigeminal neuralgic pain using [11C] Diprenorphine and positron emission tomography.
Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism, 1999Co-Authors: Anthony K. P. Jones, V J Cunningham, Terry Jones, Niel D. Kitchen, Hiroshi Watabe, Savinda K. Luthra, David G. T. ThomasAbstract:The binding of [C-11]Diprenorphine to mu, kappa, and delta subsites in cortical and subcortical structures was measured by positron emission tomography in vivo in six patients before and after surgical relief of trigeminal neuralgia pain. The volume of distribution of [C-11]Diprenorphine binding was significantly increased after thermocoagulation of the relevant trigeminal division in the following areas: prefrontal, insular, perigenual, mid-cingulate and inferior parietal cortices, basal ganglia, and thalamus bilaterally. In addition to the pain relief associated with the surgical procedure, there also was an improvement in anxiety and depression scores. In the context of other studies, these changes in binding most likely resulted from the change in the pain state. The results suggest an increased occupancy by endogenous opioid peptides during trigeminal pain but cannot exclude coexistent down-regulation of binding sites.
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Automated radiosyntheses of [6-O-methyl-11C]Diprenorphine and [6-O-methyl-11C]buprenorphine from 3-O-trityl protected precursors
Applied Radiation and Isotopes, 1994Co-Authors: Sajinder K. Luthra, Frank Brady, Anthony K. P. Jones, D. R. Turton, David J. Brown, Keith Dowsett, S.l. Waters, Ray W. Matthews, J.c. CrowderAbstract:Abstract The antagonist [6- O -methyl- 11 C]Diprenorphine and the mixed agonist/antagonist [6- O -methyl- 11 C]buprenorphine, radioligands for studying the opioid receptor system in vivo with positron emission tomography, were prepared by O -methylation of (3- O -trityl,6-desmethyl)Diprenorphine and [3- O -trityl,6-desmethyl]buprenorphine, respectively, with [ 11 C]iodomethane. The use of the base-stable, acid labile trityl protecting group minimizes the formation of byproducts and allows reproducible radiosyntheses. The two-step syntheses were carried out in a fully automated system giving [6- O -methyl- 11 C]Diprenorphine in a 13–19% radiochemical yield with a sp. act. of 15.5–23.8 GBq μmol −1 at EOS. The preparation takes 45 min from EOB. Similarly, [6- O -methyl- 11 C]buprenorphine is prepared in 50 min from EOB in 12.6–17% radiochemical yield, with a specific activity of 12.8–21.8 GBq μmol −1 at EOS. 13 C and 1 H NMR studies were used to characterize Diprenorphine and buprenorphine derivatives and, in particular, to confirm the position of methylation.
J. Soranzo - One of the best experts on this subject based on the ideXlab platform.
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1895 – Cerebral opioid activity in patients with restricting-type anorexia nervosa before and after weight recovery: a [11c]Diprenorphine pet study
European Psychiatry, 2013Co-Authors: J. Soranzo, Nicolas Costes, N. Germain-zito, D. Le Bars, S. Billard, François Lang, Bruno Estour, Bogdan GaluscaAbstract:Introduction Opioid peripheral abnormalities were described in anorexia nervosa (AN). Until now no data have been published on cerebral activity of opioid system in these subjects. Diprenorphine is a ligand with non-specific binding to opiates receptors μ, κ and δ. Aim To evaluate in vivo brain opioid receptors binding potential (BP) in patients with lean and recovered from restrictive-type AN by comparison with controls and the relationship with eating-related psychochological and hormonal traits. Methods In 17 lean restrictive-type AN patients, 15 recovered AN subjects and 15 age-matched controls we assessed in vivo [ 11 C]Diprenorphine binding by brain positron emission tomography and eating-related psychopathological traits. Inter-groups differences in [ 11 C]Diprenorphine binding were evaluated by voxel-based analyses. Results Lean restrictive AN and recovered AN patients presented with similar decreased [ 11 C]Diprenorphine binding in bilateral medial frontal cortex and temporo-parietal cortex. We noted a lower BP in hypothalamo-pituitary structures and also in anterior cingulate gyrus in lean AN patients. Additionally, only recovered AN patients presented with a decreased [ 11 C]Diprenorphine binding in caudate nuclei and putamen. Direct correlations were found between the anterior cingulate gyrus BP and mean cortisol and between the left amygdala [ 11 C]Diprenorphine binding and eating concern score. Conclusion The opioid system is widely affected in AN even after recovery in regions known to be involved in the neurocircuitry of addiction and support the hypothesis of an organic dysfunction in AN.
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1895 cerebral opioid activity in patients with restricting type anorexia nervosa before and after weight recovery a 11c Diprenorphine pet study
European Psychiatry, 2013Co-Authors: J. Soranzo, Nicolas Costes, S. Billard, François Lang, Bruno Estour, N Germainzito, Le D Bars, Bogdan GaluscaAbstract:Introduction Opioid peripheral abnormalities were described in anorexia nervosa (AN). Until now no data have been published on cerebral activity of opioid system in these subjects. Diprenorphine is a ligand with non-specific binding to opiates receptors μ, κ and δ. Aim To evaluate in vivo brain opioid receptors binding potential (BP) in patients with lean and recovered from restrictive-type AN by comparison with controls and the relationship with eating-related psychochological and hormonal traits. Methods In 17 lean restrictive-type AN patients, 15 recovered AN subjects and 15 age-matched controls we assessed in vivo [ 11 C]Diprenorphine binding by brain positron emission tomography and eating-related psychopathological traits. Inter-groups differences in [ 11 C]Diprenorphine binding were evaluated by voxel-based analyses. Results Lean restrictive AN and recovered AN patients presented with similar decreased [ 11 C]Diprenorphine binding in bilateral medial frontal cortex and temporo-parietal cortex. We noted a lower BP in hypothalamo-pituitary structures and also in anterior cingulate gyrus in lean AN patients. Additionally, only recovered AN patients presented with a decreased [ 11 C]Diprenorphine binding in caudate nuclei and putamen. Direct correlations were found between the anterior cingulate gyrus BP and mean cortisol and between the left amygdala [ 11 C]Diprenorphine binding and eating concern score. Conclusion The opioid system is widely affected in AN even after recovery in regions known to be involved in the neurocircuitry of addiction and support the hypothesis of an organic dysfunction in AN.
Bruno Estour - One of the best experts on this subject based on the ideXlab platform.
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1895 – Cerebral opioid activity in patients with restricting-type anorexia nervosa before and after weight recovery: a [11c]Diprenorphine pet study
European Psychiatry, 2013Co-Authors: J. Soranzo, Nicolas Costes, N. Germain-zito, D. Le Bars, S. Billard, François Lang, Bruno Estour, Bogdan GaluscaAbstract:Introduction Opioid peripheral abnormalities were described in anorexia nervosa (AN). Until now no data have been published on cerebral activity of opioid system in these subjects. Diprenorphine is a ligand with non-specific binding to opiates receptors μ, κ and δ. Aim To evaluate in vivo brain opioid receptors binding potential (BP) in patients with lean and recovered from restrictive-type AN by comparison with controls and the relationship with eating-related psychochological and hormonal traits. Methods In 17 lean restrictive-type AN patients, 15 recovered AN subjects and 15 age-matched controls we assessed in vivo [ 11 C]Diprenorphine binding by brain positron emission tomography and eating-related psychopathological traits. Inter-groups differences in [ 11 C]Diprenorphine binding were evaluated by voxel-based analyses. Results Lean restrictive AN and recovered AN patients presented with similar decreased [ 11 C]Diprenorphine binding in bilateral medial frontal cortex and temporo-parietal cortex. We noted a lower BP in hypothalamo-pituitary structures and also in anterior cingulate gyrus in lean AN patients. Additionally, only recovered AN patients presented with a decreased [ 11 C]Diprenorphine binding in caudate nuclei and putamen. Direct correlations were found between the anterior cingulate gyrus BP and mean cortisol and between the left amygdala [ 11 C]Diprenorphine binding and eating concern score. Conclusion The opioid system is widely affected in AN even after recovery in regions known to be involved in the neurocircuitry of addiction and support the hypothesis of an organic dysfunction in AN.
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1895 cerebral opioid activity in patients with restricting type anorexia nervosa before and after weight recovery a 11c Diprenorphine pet study
European Psychiatry, 2013Co-Authors: J. Soranzo, Nicolas Costes, S. Billard, François Lang, Bruno Estour, N Germainzito, Le D Bars, Bogdan GaluscaAbstract:Introduction Opioid peripheral abnormalities were described in anorexia nervosa (AN). Until now no data have been published on cerebral activity of opioid system in these subjects. Diprenorphine is a ligand with non-specific binding to opiates receptors μ, κ and δ. Aim To evaluate in vivo brain opioid receptors binding potential (BP) in patients with lean and recovered from restrictive-type AN by comparison with controls and the relationship with eating-related psychochological and hormonal traits. Methods In 17 lean restrictive-type AN patients, 15 recovered AN subjects and 15 age-matched controls we assessed in vivo [ 11 C]Diprenorphine binding by brain positron emission tomography and eating-related psychopathological traits. Inter-groups differences in [ 11 C]Diprenorphine binding were evaluated by voxel-based analyses. Results Lean restrictive AN and recovered AN patients presented with similar decreased [ 11 C]Diprenorphine binding in bilateral medial frontal cortex and temporo-parietal cortex. We noted a lower BP in hypothalamo-pituitary structures and also in anterior cingulate gyrus in lean AN patients. Additionally, only recovered AN patients presented with a decreased [ 11 C]Diprenorphine binding in caudate nuclei and putamen. Direct correlations were found between the anterior cingulate gyrus BP and mean cortisol and between the left amygdala [ 11 C]Diprenorphine binding and eating concern score. Conclusion The opioid system is widely affected in AN even after recovery in regions known to be involved in the neurocircuitry of addiction and support the hypothesis of an organic dysfunction in AN.
Nicolas Costes - One of the best experts on this subject based on the ideXlab platform.
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1895 – Cerebral opioid activity in patients with restricting-type anorexia nervosa before and after weight recovery: a [11c]Diprenorphine pet study
European Psychiatry, 2013Co-Authors: J. Soranzo, Nicolas Costes, N. Germain-zito, D. Le Bars, S. Billard, François Lang, Bruno Estour, Bogdan GaluscaAbstract:Introduction Opioid peripheral abnormalities were described in anorexia nervosa (AN). Until now no data have been published on cerebral activity of opioid system in these subjects. Diprenorphine is a ligand with non-specific binding to opiates receptors μ, κ and δ. Aim To evaluate in vivo brain opioid receptors binding potential (BP) in patients with lean and recovered from restrictive-type AN by comparison with controls and the relationship with eating-related psychochological and hormonal traits. Methods In 17 lean restrictive-type AN patients, 15 recovered AN subjects and 15 age-matched controls we assessed in vivo [ 11 C]Diprenorphine binding by brain positron emission tomography and eating-related psychopathological traits. Inter-groups differences in [ 11 C]Diprenorphine binding were evaluated by voxel-based analyses. Results Lean restrictive AN and recovered AN patients presented with similar decreased [ 11 C]Diprenorphine binding in bilateral medial frontal cortex and temporo-parietal cortex. We noted a lower BP in hypothalamo-pituitary structures and also in anterior cingulate gyrus in lean AN patients. Additionally, only recovered AN patients presented with a decreased [ 11 C]Diprenorphine binding in caudate nuclei and putamen. Direct correlations were found between the anterior cingulate gyrus BP and mean cortisol and between the left amygdala [ 11 C]Diprenorphine binding and eating concern score. Conclusion The opioid system is widely affected in AN even after recovery in regions known to be involved in the neurocircuitry of addiction and support the hypothesis of an organic dysfunction in AN.
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1895 cerebral opioid activity in patients with restricting type anorexia nervosa before and after weight recovery a 11c Diprenorphine pet study
European Psychiatry, 2013Co-Authors: J. Soranzo, Nicolas Costes, S. Billard, François Lang, Bruno Estour, N Germainzito, Le D Bars, Bogdan GaluscaAbstract:Introduction Opioid peripheral abnormalities were described in anorexia nervosa (AN). Until now no data have been published on cerebral activity of opioid system in these subjects. Diprenorphine is a ligand with non-specific binding to opiates receptors μ, κ and δ. Aim To evaluate in vivo brain opioid receptors binding potential (BP) in patients with lean and recovered from restrictive-type AN by comparison with controls and the relationship with eating-related psychochological and hormonal traits. Methods In 17 lean restrictive-type AN patients, 15 recovered AN subjects and 15 age-matched controls we assessed in vivo [ 11 C]Diprenorphine binding by brain positron emission tomography and eating-related psychopathological traits. Inter-groups differences in [ 11 C]Diprenorphine binding were evaluated by voxel-based analyses. Results Lean restrictive AN and recovered AN patients presented with similar decreased [ 11 C]Diprenorphine binding in bilateral medial frontal cortex and temporo-parietal cortex. We noted a lower BP in hypothalamo-pituitary structures and also in anterior cingulate gyrus in lean AN patients. Additionally, only recovered AN patients presented with a decreased [ 11 C]Diprenorphine binding in caudate nuclei and putamen. Direct correlations were found between the anterior cingulate gyrus BP and mean cortisol and between the left amygdala [ 11 C]Diprenorphine binding and eating concern score. Conclusion The opioid system is widely affected in AN even after recovery in regions known to be involved in the neurocircuitry of addiction and support the hypothesis of an organic dysfunction in AN.