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Hendry E, McCallister B, Elman DJ, Freeman R, Borsook D, Elman I. Validity of mental and physical stress models. Neurosci Biobehav Rev 2024; 158:105566. [PMID: 38307304 PMCID: PMC11082879 DOI: 10.1016/j.neubiorev.2024.105566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Revised: 01/13/2024] [Accepted: 01/27/2024] [Indexed: 02/04/2024]
Abstract
Different stress models are employed to enhance our understanding of the underlying mechanisms and explore potential interventions. However, the utility of these models remains a critical concern, as their validities may be limited by the complexity of stress processes. Literature review revealed that both mental and physical stress models possess reasonable construct and criterion validities, respectively reflected in psychometrically assessed stress ratings and in activation of the sympathoadrenal system and the hypothalamic-pituitary-adrenal axis. The findings are less robust, though, in the pharmacological perturbations' domain, including such agents as adenosine or dobutamine. Likewise, stress models' convergent- and discriminant validity vary depending on the stressors' nature. Stress models share similarities, but also have important differences regarding their validities. Specific traits defined by the nature of the stressor stimulus should be taken into consideration when selecting stress models. Doing so can personalize prevention and treatment of stress-related antecedents, its acute processing, and chronic sequelae. Further work is warranted to refine stress models' validity and customize them so they commensurate diverse populations and circumstances.
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Affiliation(s)
- Erin Hendry
- Center for Autonomic and Peripheral Nerve Disorders, Harvard Medical School, Boston, MA, USA; Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Brady McCallister
- Center for Autonomic and Peripheral Nerve Disorders, Harvard Medical School, Boston, MA, USA
| | - Dan J Elman
- Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Roy Freeman
- Center for Autonomic and Peripheral Nerve Disorders, Harvard Medical School, Boston, MA, USA; Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - David Borsook
- Departments of Psychiatry and Radiology, Massachusetts General Hospital, Harvard Medical School, Department of Anesthesiology, Harvard Medical School, Boston, MA, USA.
| | - Igor Elman
- Department of Psychiatry, Cambridge Health Alliance, Harvard Medical School, Cambridge, MA, USA
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2
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Li N, Wang C, Zhao Y, Wang Y, Gao T, Yu Y, Wang G, Zhang L. STING controls opioid-induced itch and chronic itch via spinal tank-binding kinase 1-dependent type I interferon response in mice. J Neuroinflammation 2023; 20:101. [PMID: 37122031 PMCID: PMC10150483 DOI: 10.1186/s12974-023-02783-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2023] [Accepted: 04/20/2023] [Indexed: 05/02/2023] Open
Abstract
BACKGROUND Patients receiving epidural or intrathecal opioids administration for neuraxial analgesia frequently suffer from an irritating itch. STING (stimulator of interferon genes), an innate immune modulator, is strongly implicated in pain pathogenesis via neuron-immune modulation. Given that pain and itch share some common neurocircuits, we evaluate the therapeutic potential of STING agonists in opioid-induced itch and chronic itch. METHODS Opioids (morphine, fentanyl and sufentanil) were intrathecally injected to induce acute itch. Chronic itch was induced by dry skin and contact dermatitis. Opioids analgesic effect, itch-induced scratching behavior, spinal expression of STING, phosphorylation of TBK1 (tank-binding kinase 1), IRF3 (interferon regulatory factor-3) and ERK (extracellular signal-regulated kinase), as well as production of IFN-α and IFN-β were examined. STING agonists (DMXAA and ADU-S100), TBK1 inhibitor, recombinant IFN-α and IFN-β elucidated the mechanism and treatment of itch. Whole-brain functional connectivity was evaluated using resting-state fMRI. RESULTS We report the primary expression of STING protein by the spinal dorsal horn neurons. Intraperitoneal injection of DMXAA dose-dependently reduces morphine-induced scratch bouts, without impairing morphine antinociception. Simultaneously, DMXAA alleviates fentanyl- and sufentanil-induced itching-like behavior, and chronic scratching behavior caused by dry skin and contact dermatitis. Furthermore, DMXAA drastically increases spinal phosphorylation of TBK1 and IRF3 following morphine exposure, dry skin and contact dermatitis. DMXAA-induced anti-pruritus effects and spinal productions of IFN-α and IFN-β are compensated by intrathecal delivery of the TBK1 inhibitor. Also, ADU-S100, recombinant IFN-α and IFN-β exhibits remarkable attenuation in scratching behaviors after morphine injection and dermatitis. Recombinant IFN-α inhibits morphine-induced spinal phosphorylation of ERK. Finally, DMXAA prevents dermatitis-induced the increase of cerebral functional connectivity between regions of interests such as primary somatosensory cortex, piriform cortex, retrosplenial cortex, colliculus and ventral thalamus. CONCLUSIONS STING activation confers protection against opioid-induced itch and chronic itch through spinal up-regulation of TBK1-IRF3-type I interferon cascades in mice, suggesting that STING agonists are promising candidates in translational development for pruritus relief.
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Affiliation(s)
- Nan Li
- Department of Anesthesiology, Tianjin Medical University General Hospital, Tianjin, 300052, China
- Tianjin Research Institute of Anesthesiology, Tianjin, 300052, China
| | - Chunyan Wang
- Department of Anesthesiology, Tianjin Medical University General Hospital, Tianjin, 300052, China
- Tianjin Research Institute of Anesthesiology, Tianjin, 300052, China
| | - Yuying Zhao
- Department of Anesthesiology, Tianjin Medical University General Hospital, Tianjin, 300052, China
- Tianjin Research Institute of Anesthesiology, Tianjin, 300052, China
| | - Yigang Wang
- Department of Anesthesiology, Tianjin Medical University General Hospital, Tianjin, 300052, China
- Tianjin Research Institute of Anesthesiology, Tianjin, 300052, China
| | - Tianyu Gao
- Department of Anesthesiology, Tianjin Medical University General Hospital, Tianjin, 300052, China
- Tianjin Research Institute of Anesthesiology, Tianjin, 300052, China
| | - Yonghao Yu
- Department of Anesthesiology, Tianjin Medical University General Hospital, Tianjin, 300052, China
- Tianjin Research Institute of Anesthesiology, Tianjin, 300052, China
| | - Guolin Wang
- Department of Anesthesiology, Tianjin Medical University General Hospital, Tianjin, 300052, China
- Tianjin Research Institute of Anesthesiology, Tianjin, 300052, China
| | - Linlin Zhang
- Department of Anesthesiology, Tianjin Medical University General Hospital, Tianjin, 300052, China.
- Tianjin Research Institute of Anesthesiology, Tianjin, 300052, China.
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den Boer JA, de Vries EJ, Borra RJ, Waarde AV, Lammertsma AA, Dierckx RA. Role of Brain Imaging in Drug Development for Psychiatry. Curr Rev Clin Exp Pharmacol 2022; 17:46-71. [DOI: 10.2174/1574884716666210322143458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 12/17/2020] [Accepted: 01/06/2021] [Indexed: 11/22/2022]
Abstract
Background:
Over the last decades, many brain imaging studies have contributed to
new insights in the pathogenesis of psychiatric disease. However, in spite of these developments,
progress in the development of novel therapeutic drugs for prevalent psychiatric health conditions
has been limited.
Objective:
In this review, we discuss translational, diagnostic and methodological issues that have
hampered drug development in CNS disorders with a particular focus on psychiatry. The role of
preclinical models is critically reviewed and opportunities for brain imaging in early stages of drug
development using PET and fMRI are discussed. The role of PET and fMRI in drug development
is reviewed emphasizing the need to engage in collaborations between industry, academia and
phase I units.
Conclusion:
Brain imaging technology has revolutionized the study of psychiatric illnesses, and
during the last decade, neuroimaging has provided valuable insights at different levels of analysis
and brain organization, such as effective connectivity (anatomical), functional connectivity patterns
and neurochemical information that may support both preclinical and clinical drug development.
Since there is no unifying pathophysiological theory of individual psychiatric syndromes and since
many symptoms cut across diagnostic boundaries, a new theoretical framework has been proposed
that may help in defining new targets for treatment and thus enhance drug development in CNS diseases.
In addition, it is argued that new proposals for data-mining and mathematical modelling as
well as freely available databanks for neural network and neurochemical models of rodents combined
with revised psychiatric classification will lead to new validated targets for drug development.
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Affiliation(s)
| | - Erik J.F. de Vries
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Ronald J.H. Borra
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Aren van Waarde
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Adriaan A. Lammertsma
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Rudi A. Dierckx
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
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A white paper on a neurodevelopmental framework for drug discovery in autism and other neurodevelopmental disorders. Eur Neuropsychopharmacol 2021; 48:49-88. [PMID: 33781629 DOI: 10.1016/j.euroneuro.2021.02.020] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 02/08/2021] [Accepted: 02/15/2021] [Indexed: 12/20/2022]
Abstract
In the last decade there has been a revolution in terms of genetic findings in neurodevelopmental disorders (NDDs), with many discoveries critical for understanding their aetiology and pathophysiology. Clinical trials in single-gene disorders such as fragile X syndrome highlight the challenges of investigating new drug targets in NDDs. Incorporating a developmental perspective into the process of drug development for NDDs could help to overcome some of the current difficulties in identifying and testing new treatments. This paper provides a summary of the proceedings of the 'New Frontiers Meeting' on neurodevelopmental disorders organised by the European College of Neuropsychopharmacology in conjunction with the Innovative Medicines Initiative-sponsored AIMS-2-TRIALS consortium. It brought together experts in developmental genetics, autism, NDDs, and clinical trials from academia and industry, regulators, patient and family associations, and other stakeholders. The meeting sought to provide a platform for focused communication on scientific insights, challenges, and methodologies that might be applicable to the development of CNS treatments from a neurodevelopmental perspective. Multidisciplinary translational consortia to develop basic and clinical research in parallel could be pivotal to advance knowledge in the field. Although implementation of clinical trials for NDDs in paediatric populations is widely acknowledged as essential, safety concerns should guide each aspect of their design. Industry and academia should join forces to improve knowledge of the biology of brain development, identify the optimal timing of interventions, and translate these findings into new drugs, allowing for the needs of users and families, with support from regulatory agencies.
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Molecular and Functional Imaging in Central Nervous System Drug Development. Mol Imaging 2021. [DOI: 10.1016/b978-0-12-816386-3.00084-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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6
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Makovac E, Dipasquale O, Jackson JB, Medina S, O'Daly O, O'Muircheartaigh J, de Lara Rubio A, Williams SCR, McMahon SB, Howard MA. Sustained perturbation in functional connectivity induced by cold pain. Eur J Pain 2020; 24:1850-1861. [PMID: 32648623 DOI: 10.1002/ejp.1633] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 06/27/2020] [Accepted: 07/05/2020] [Indexed: 11/10/2022]
Abstract
BACKGROUND Functional connectivity (FC) perturbations have been reported in multiple chronic pain phenotypes, but the nature of reported changes varies between cohorts and may relate to the consequences of living with chronic-pain related comorbidities, such as anxiety and depression. Healthy volunteer studies provide opportunities to study the effects of tonic noxious stimulation independently of these sequelae. Connectivity changes in task negative and positive networks, for example, the default mode and salience networks (DMN/SN), respectively, have been described, but how these and other connectivity networks, for example, those governing descending pain control are affected by the presence of tonic, noxious stimulation in healthy, pain-free individuals, remains unknown. METHOD In 20 healthy volunteers, we assessed FC prior to, during, and following tonic cold painful stimulation in the ventromedial prefrontal cortex (vmPFC), rostral anterior insula (rAI), subgenual anterior cingulate cortex (ACC) and periaqueductal grey (PAG). We also recorded subjectively reported pain using a computerised visual analogue scale. RESULTS We saw DMN FC changes during painful stimulation and that inter-network connectivity between the rAI with the vmPFC increased during pain, whereas PAG-precuneus FC decreased. Pain-induced FC alterations persisted following noxious stimulation. FC changes related to the magnitude of individuals' subjectively reported pain. CONCLUSIONS We demonstrate FC changes during and following tonic cold-pain in healthy participants. Similarities between our findings and reports of patients with chronic pain suggest that some FC changes observed in these patients may relate to the presence of an ongoing afferent nociceptive drive. SIGNIFICANCE How pain-related resting state networks are affected by tonic cold-pain remains unknown. We investigated functional connectivity alterations during and following tonic cold pain in healthy volunteers. Cold pain perturbed the functional connectivity of the ventro-medial prefrontal cortex, anterior insula, and the periacquaductal grey area. These connectivity changes were associated with the magnitude of individuals' reported pain. We suggest that some connectivity changes described in chronic pain patients may be due to an ongoing afferent peripheral drive.
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Affiliation(s)
- Elena Makovac
- Department of Neuroimaging, King's College London, London, UK
- Wolfson Centre for Age Related Diseases, King's College London, London, UK
| | | | - Jade B Jackson
- Department of Neuroimaging, King's College London, London, UK
- Wolfson Centre for Age Related Diseases, King's College London, London, UK
| | - Sonia Medina
- Department of Neuroimaging, King's College London, London, UK
- Wolfson Centre for Age Related Diseases, King's College London, London, UK
| | - Owen O'Daly
- Department of Neuroimaging, King's College London, London, UK
| | - Jonathan O'Muircheartaigh
- Department of Neuroimaging, King's College London, London, UK
- Sackler Institute for Translational Neurodevelopment, King's College London, London, UK
- Centre for the Developing Brain, King's College London, London, UK
- MRC Centre for Neurodevelopmental Disorders, King's College London, London, UK
| | | | | | - Stephen B McMahon
- Wolfson Centre for Age Related Diseases, King's College London, London, UK
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Borsook D, Upadhyay J, Hargreaves R, Wager T. Enhancing Choice and Outcomes for Therapeutic Trials in Chronic Pain: N-of-1 + Imaging (+ i). Trends Pharmacol Sci 2020; 41:85-98. [DOI: 10.1016/j.tips.2019.12.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 11/27/2019] [Accepted: 12/04/2019] [Indexed: 10/25/2022]
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Neuroimaging-based pain biomarkers: definitions, clinical and research applications, and evaluation frameworks to achieve personalized pain medicine. Pain Rep 2019; 4:e762. [PMID: 31579854 PMCID: PMC6727999 DOI: 10.1097/pr9.0000000000000762] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2019] [Revised: 04/28/2019] [Accepted: 05/15/2019] [Indexed: 12/22/2022] Open
Abstract
One of the key ambitions of neuroimaging-based pain biomarker research is to augment patient and clinician reporting of clinically relevant phenomena with neural measures for prediction, prognosis, and detection of pain. Despite years of productive research on the neuroimaging of pain, such applications have seen little advancement. However, recent developments in identifying brain-based biomarkers of pain through advances in technology and multivariate pattern analysis provide some optimism. Here, we (1) define and review the different types of potential neuroimaging-based biomarkers, their clinical and research applications, and their limitations and (2) describe frameworks for evaluation of pain biomarkers used in other fields (eg, genetics, cancer, cardiovascular disease, immune system disorders, and rare diseases) to achieve broad clinical and research utility and minimize the risks of misapplication of this emerging technology. To conclude, we discuss future directions for neuroimaging-based biomarker research to achieve the goal of personalized pain medicine.
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Nasseef MT, Singh JP, Ehrlich AT, McNicholas M, Park DW, Ma W, Kulkarni P, Kieffer BL, Darcq E. Oxycodone-Mediated Activation of the Mu Opioid Receptor Reduces Whole Brain Functional Connectivity in Mice. ACS Pharmacol Transl Sci 2019; 2:264-274. [PMID: 32259060 DOI: 10.1021/acsptsci.9b00021] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Indexed: 12/17/2022]
Abstract
Oxycodone is a potent medicinal opioid analgesic to treat pain. It is also addictive and a main cause for the current opioid crisis. At present, the impact of oxycodone on coordinated brain network activities, and contribution of the mu opioid receptor (MOR) to these effects, is unknown. We used pharmacological magnetic resonance imaging in mice to characterize MOR-mediated oxycodone effects on whole-brain functional connectivity (FC). Control (CTL) and MOR knockout (KO) animals were imaged under dexmedetomidine in a 7Tesla scanner. Acquisition was performed continuously before and after 2 mg/kg oxycodone administration (analgesic in CTL mice). Independent component analysis (data-driven) produced a correlation matrix, showing widespread oxycodone-induced reduction of FC across 71 components. Isocortex, nucleus accumbens (NAc), pontine reticular nucleus, and periacqueducal gray (PAG) components showed the highest number of significant changes. Seed-to-voxel FC analysis (hypothesis-driven) was then focused on PAG and NAc considered key pain and reward centers. The two seeds showed reduced FC with 8 and 22 Allen Brain Atlas-based regions, respectively, in CTL but not KO mice. Further seed-to-seed quantification showed highest FC modifications of both PAG and NAc seeds with hypothalamic and amygdalar areas, as well as between them, revealing the strongest impact across reward and aversion/pain centers of the brain. In conclusion, we demonstrate that oxycodone reduces brain communication in a MOR-dependent manner, and establish a preliminary whole-brain FC signature of oxycodone. This proof-of-principle study provides a unique platform and reference data set to test other MOR opioid agonists and perhaps discover new mechanisms and FC biomarkers predicting safer analgesics.
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Affiliation(s)
- Md Taufiq Nasseef
- Douglas Hospital Research Center, Department of Psychiatry, School of Medicine, McGill University, Montreal, Quebec H4H 1R3, Canada
| | - Jai Puneet Singh
- Douglas Hospital Research Center, Department of Psychiatry, School of Medicine, McGill University, Montreal, Quebec H4H 1R3, Canada
| | - Aliza T Ehrlich
- Douglas Hospital Research Center, Department of Psychiatry, School of Medicine, McGill University, Montreal, Quebec H4H 1R3, Canada
| | - Michael McNicholas
- Douglas Hospital Research Center, Department of Psychiatry, School of Medicine, McGill University, Montreal, Quebec H4H 1R3, Canada
| | - Da Woon Park
- Douglas Hospital Research Center, Department of Psychiatry, School of Medicine, McGill University, Montreal, Quebec H4H 1R3, Canada
| | - Weiya Ma
- Douglas Hospital Research Center, Department of Psychiatry, School of Medicine, McGill University, Montreal, Quebec H4H 1R3, Canada
| | - Praveen Kulkarni
- Center for Translational Neuro-Imaging, Northeastern University, Boston, Massachusetts 02115, United States
| | - Brigitte L Kieffer
- Douglas Hospital Research Center, Department of Psychiatry, School of Medicine, McGill University, Montreal, Quebec H4H 1R3, Canada
| | - Emmanuel Darcq
- Douglas Hospital Research Center, Department of Psychiatry, School of Medicine, McGill University, Montreal, Quebec H4H 1R3, Canada
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Horta M, Ziaei M, Lin T, Porges EC, Fischer H, Feifel D, Spreng RN, Ebner NC. Oxytocin alters patterns of brain activity and amygdalar connectivity by age during dynamic facial emotion identification. Neurobiol Aging 2019; 78:42-51. [PMID: 30870779 DOI: 10.1016/j.neurobiolaging.2019.01.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Revised: 01/03/2019] [Accepted: 01/21/2019] [Indexed: 10/27/2022]
Abstract
Aging is associated with increased difficulty in facial emotion identification, possibly due to age-related network change. The neuropeptide oxytocin (OT) facilitates emotion identification, but this is understudied in aging. To determine the effects of OT on dynamic facial emotion identification across adulthood, 46 young and 48 older participants self-administered intranasal OT or a placebo in a randomized, double-blind procedure. Older participants were slower and less accurate in identifying emotions. Although there was no behavioral treatment effect, partial least squares analysis supported treatment effects on brain patterns during emotion identification that varied by age and emotion. For young participants, OT altered the processing of sadness and happiness, whereas for older participants, OT only affected the processing of sadness (15.3% covariance, p = 0.004). Furthermore, seed partial least squares analysis showed that older participants in the OT group recruited a large-scale amygdalar network that was positively correlated for anger, fear, and happiness, whereas older participants in the placebo group recruited a smaller, negatively correlated network (7% covariance, p = 0.002). Advancing the literature, these findings show that OT alters brain activity and amygdalar connectivity by age and emotion.
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Affiliation(s)
- Marilyn Horta
- Department of Psychology, University of Florida, Gainesville, FL, USA.
| | - Maryam Ziaei
- Centre for Advanced Imaging, University of Queensland, Brisbane, Australia
| | - Tian Lin
- Department of Psychology, University of Florida, Gainesville, FL, USA
| | - Eric C Porges
- Department of Clinical and Health Psychology, Center for Cognitive Aging and Memory, University of Florida, Gainesville, FL, USA
| | - Håkan Fischer
- Department of Psychology, Stockholm University, Stockholm, Sweden
| | - David Feifel
- Department of Psychiatry, University of California, San Diego, CA, USA
| | - R Nathan Spreng
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada; Departments of Psychology and Psychiatry, McGill University, Montreal, Quebec, Canada
| | - Natalie C Ebner
- Department of Psychology, University of Florida, Gainesville, FL, USA; Department of Clinical and Health Psychology, Center for Cognitive Aging and Memory, University of Florida, Gainesville, FL, USA; Department of Aging and Geriatric Research, Institute on Aging, University of Florida, Gainesville, FL, USA
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Abstract
PURPOSE OF REVIEW The goal of this review is to provide a broad overview of the current understanding of mechanisms underlying bone and joint pain. RECENT FINDINGS Bone or joint pathology is generally accompanied by local release of pro-inflammatory cytokines, growth factors, and neurotransmitters that activate and sensitize sensory nerves resulting in an amplified pain signal. Modulation of the pain signal within the spinal cord and brain that result in net increased facilitation is proposed to contribute to the development of chronic pain. Great strides have been made in our understanding of mechanisms underlying bone and joint pain that will guide development of improved therapeutic options for these patients. Continued research is required for improved understanding of mechanistic differences driving different components of bone and/or joint pain such as movement related pain compared to persistent background pain. Advances will guide development of more individualized and comprehensive therapeutic options.
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Affiliation(s)
- Joshua Havelin
- Center for Excellence in the Neurosciences, University of New England, Biddeford, ME, 04043, USA
- Graduate School of Biomedical Science and Engineering, University of Maine, Orono, ME, 04469, USA
| | - Tamara King
- Center for Excellence in the Neurosciences, University of New England, Biddeford, ME, 04043, USA.
- Graduate School of Biomedical Science and Engineering, University of Maine, Orono, ME, 04469, USA.
- Department of Biomedical Sciences, College of Osteopathic Medicine, University of New England, 11 Hills Beach Rd., Biddeford, ME, 04005, USA.
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van den Brink WJ, Hankemeier T, van der Graaf PH, de Lange ECM. Bundling arrows: improving translational CNS drug development by integrated PK/PD-metabolomics. Expert Opin Drug Discov 2018. [DOI: 10.1080/17460441.2018.1446935] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- W. J. van den Brink
- Division of Systems Biomedicine and Pharmacology, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands
| | - T. Hankemeier
- Division of Systems Biomedicine and Pharmacology, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands
| | - P. H. van der Graaf
- Division of Systems Biomedicine and Pharmacology, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands
- Certara QSP, Canterbury Innovation House, Canterbury, United Kingdom
| | - E. C. M. de Lange
- Division of Systems Biomedicine and Pharmacology, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands
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Nyholt DR, Borsook D, Griffiths LR. Migrainomics — identifying brain and genetic markers of migraine. Nat Rev Neurol 2017; 13:725-741. [DOI: 10.1038/nrneurol.2017.151] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Farokhnia M, Momenan R, Leggio L. Commentary on Schmitz et al. (2017): Advancing medication development for addiction-behavioral and neuroimaging outcomes as indirect biomarkers of target engagement. Addiction 2017; 112:1869-1870. [PMID: 28891145 DOI: 10.1111/add.13959] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Accepted: 07/19/2017] [Indexed: 12/17/2022]
Affiliation(s)
- Mehdi Farokhnia
- Section on Clinical Psychoneuroendocrinology and Neuropsychopharmacolgy, NIAAA and NIDA, NIH, Bethesda, MD, USA
| | - Reza Momenan
- Clinical NeuroImaging Research Core, NIAAA, NIH, Bethesda, MD, USA
| | - Lorenzo Leggio
- Section on Clinical Psychoneuroendocrinology and Neuropsychopharmacolgy, NIAAA and NIDA, NIH, Bethesda, MD, USA.,Center for Alcohol and Addiction Studies, Department of Behavioral and Social Sciences, Brown University, Providence, RI, USA
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Yardley MM, Ray LA. Medications development for the treatment of alcohol use disorder: insights into the predictive value of animal and human laboratory models. Addict Biol 2017; 22:581-615. [PMID: 26833803 DOI: 10.1111/adb.12349] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Revised: 11/09/2015] [Accepted: 11/13/2015] [Indexed: 12/20/2022]
Abstract
Development of effective treatments for alcohol use disorder (AUD) represents an important public health goal. This review provides a summary of completed preclinical and clinical studies testing pharmacotherapies for the treatment of AUD. We discuss opportunities for improving the translation from preclinical findings to clinical trial outcomes, focusing on the validity and predictive value of animal and human laboratory models of AUD. Specifically, while preclinical studies of medications development have offered important insights into the neurobiology of the disorder and alcohol's molecular targets, limitations include the lack of standardized methods and streamlined processes whereby animal studies can readily inform human studies. Behavioral pharmacology studies provide a less expensive and valuable opportunity to assess the feasibility of a pharmacotherapy prior to initiating larger scale clinical trials by providing insights into the mechanism of the drug, which can then inform recruitment, analyses, and assessments. Summary tables are provided to illustrate the wide range of preclinical, human laboratory, and clinical studies of medications development for alcoholism. Taken together, this review highlights the challenges associated with animal paradigms, human laboratory studies, and clinical trials with the overarching goal of advancing treatment development and highlighting opportunities to bridge the gap between preclinical and clinical research.
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Affiliation(s)
- Megan M. Yardley
- Department of Psychology; University of California, Los Angeles; Los Angeles CA USA
| | - Lara A. Ray
- Department of Psychology; University of California, Los Angeles; Los Angeles CA USA
- Department of Psychiatry and Biobehavioral Sciences; University of California, Los Angeles; Los Angeles CA USA
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Mueller SM, Hogg S, Mueller JM, McKie S, Itin P, Reinhardt J, Griffiths CE, Kleyn CE. Functional magnetic resonance imaging in dermatology: The skin, the brain and the invisible. Exp Dermatol 2017; 26:845-853. [DOI: 10.1111/exd.13305] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/17/2017] [Indexed: 01/05/2023]
Affiliation(s)
- Simon M. Mueller
- Department of Dermatology; University Hospital Basel; Basel Switzerland
- Dermatology Centre; The Manchester Academic Health Science Centre; The University of Manchester; Manchester UK
| | - Samuel Hogg
- Department of Dermatology; University Hospital Basel; Basel Switzerland
| | - Jannis M. Mueller
- Department of Neurology; Kantonsspital Muensterlingen; Muensterlingen Switzerland
| | - Shane McKie
- Neuroscience and Psychiatry Unit; The Manchester Academic Health Science Centre; The University of Manchester; Manchester UK
| | - Peter Itin
- Dermatology Centre; The Manchester Academic Health Science Centre; The University of Manchester; Manchester UK
| | - Julia Reinhardt
- Division of Diagnostic & Interventional Neuroradiology; University Hospital Basel; Basel Switzerland
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17
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Khalili-Mahani N, Rombouts SARB, van Osch MJP, Duff EP, Carbonell F, Nickerson LD, Becerra L, Dahan A, Evans AC, Soucy JP, Wise R, Zijdenbos AP, van Gerven JM. Biomarkers, designs, and interpretations of resting-state fMRI in translational pharmacological research: A review of state-of-the-Art, challenges, and opportunities for studying brain chemistry. Hum Brain Mapp 2017; 38:2276-2325. [PMID: 28145075 DOI: 10.1002/hbm.23516] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Revised: 11/21/2016] [Accepted: 01/04/2017] [Indexed: 12/11/2022] Open
Abstract
A decade of research and development in resting-state functional MRI (RSfMRI) has opened new translational and clinical research frontiers. This review aims to bridge between technical and clinical researchers who seek reliable neuroimaging biomarkers for studying drug interactions with the brain. About 85 pharma-RSfMRI studies using BOLD signal (75% of all) or arterial spin labeling (ASL) were surveyed to investigate the acute effects of psychoactive drugs. Experimental designs and objectives include drug fingerprinting dose-response evaluation, biomarker validation and calibration, and translational studies. Common biomarkers in these studies include functional connectivity, graph metrics, cerebral blood flow and the amplitude and spectrum of BOLD fluctuations. Overall, RSfMRI-derived biomarkers seem to be sensitive to spatiotemporal dynamics of drug interactions with the brain. However, drugs cause both central and peripheral effects, thus exacerbate difficulties related to biological confounds, structured noise from motion and physiological confounds, as well as modeling and inference testing. Currently, these issues are not well explored, and heterogeneities in experimental design, data acquisition and preprocessing make comparative or meta-analysis of existing reports impossible. A unifying collaborative framework for data-sharing and data-mining is thus necessary for investigating the commonalities and differences in biomarker sensitivity and specificity, and establishing guidelines. Multimodal datasets including sham-placebo or active control sessions and repeated measurements of various psychometric, physiological, metabolic and neuroimaging phenotypes are essential for pharmacokinetic/pharmacodynamic modeling and interpretation of the findings. We provide a list of basic minimum and advanced options that can be considered in design and analyses of future pharma-RSfMRI studies. Hum Brain Mapp 38:2276-2325, 2017. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Najmeh Khalili-Mahani
- McGill Centre for Integrative Neuroscience, Montreal Neurological Institute, McGill University, Montreal, Canada.,PERFORM Centre, Concordia University, Montreal, Canada
| | - Serge A R B Rombouts
- Department of Radiology, Leiden University Medical Centre, Leiden, The Netherlands.,Institute of Psychology and Leiden Institute for Brain and Cognition, Leiden University, Leiden, The Netherlands
| | | | - Eugene P Duff
- Institute of Psychology and Leiden Institute for Brain and Cognition, Leiden University, Leiden, The Netherlands.,Oxford Centre for Functional MRI of the Brain, Oxford University, Oxford, United Kingdom
| | | | - Lisa D Nickerson
- McLean Hospital, Belmont, Massachusetts.,Harvard Medical School, Boston, Massachusetts
| | - Lino Becerra
- Center for Pain and the Brain, Harvard Medical School & Boston Children's Hospital, Boston, Massachusetts
| | - Albert Dahan
- Department of Anesthesiology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Alan C Evans
- McGill Centre for Integrative Neuroscience, Montreal Neurological Institute, McGill University, Montreal, Canada.,McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, Canada
| | - Jean-Paul Soucy
- PERFORM Centre, Concordia University, Montreal, Canada.,McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, Canada
| | - Richard Wise
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, United Kingdom
| | - Alex P Zijdenbos
- McGill Centre for Integrative Neuroscience, Montreal Neurological Institute, McGill University, Montreal, Canada.,Biospective Inc, Montreal, Quebec, Canada
| | - Joop M van Gerven
- Centre for Human Drug Research, Leiden University Medical Centre, Leiden, The Netherlands
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18
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George E, Elman I, Becerra L, Berg S, Borsook D. Pain in an era of armed conflicts: Prevention and treatment for warfighters and civilian casualties. Prog Neurobiol 2016; 141:25-44. [PMID: 27084355 DOI: 10.1016/j.pneurobio.2016.04.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Revised: 03/23/2016] [Accepted: 04/08/2016] [Indexed: 12/13/2022]
Abstract
Chronic pain is a common squealae of military- and terror-related injuries. While its pathophysiology has not yet been fully elucidated, it may be potentially related to premorbid neuropsychobiological status, as well as to the type of injury and to the neural alterations that it may evoke. Accordingly, optimized approaches for wounded individuals should integrate primary, secondary and tertiary prevention in the form of thorough evaluation of risk factors along with specific interventions to contravene and mitigate the ensuing chronicity. Thus, Premorbid Events phase may encompass assessments of psychological and neurobiological vulnerability factors in conjunction with fostering preparedness and resilience in both military and civilian populations at risk. Injuries per se phase calls for immediate treatment of acute pain in the field by pharmacological agents that spare and even enhance coping and adaptive capabilities. The key objective of the Post Injury Events is to prevent and/or reverse maladaptive peripheral- and central neural system's processes that mediate transformation of acute to chronic pain and to incorporate timely interventions for concomitant mental health problems including post-traumatic stress disorder and addiction We suggest that the proposed continuum of care may avert more disability and suffering than the currently employed less integrated strategies. While the requirements of the armed forces present a pressing need for this integrated continuum and a framework in which it can be most readily implemented, this approach may be also instrumental for the care of civilian casualties.
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Affiliation(s)
- E George
- Center for Pain and the Brain, Harvard Medical School (HMS), United States; Department of Anesthesia, Critical Care and Pain Medicine, MGH, HMS, Boston, MA, United States; Commander, MC, USN (Ret), United States
| | - I Elman
- Center for Pain and the Brain, Harvard Medical School (HMS), United States; Department of Psychiatry, Boonshoft School of Medicine and Dayton VA Medical Center, United States; Veterans Administration Medical Center, Dayton, OH, United States
| | - L Becerra
- Center for Pain and the Brain, Harvard Medical School (HMS), United States; Department of Anesthesia, Critical Care and Pain Medicine, BCH, HMS, Boston, MA, United States; Departments of Psychiatry and Radiology, MGH, Boston, MA, United States
| | - Sheri Berg
- Center for Pain and the Brain, Harvard Medical School (HMS), United States; Department of Anesthesia, Critical Care and Pain Medicine, MGH, HMS, Boston, MA, United States
| | - D Borsook
- Center for Pain and the Brain, Harvard Medical School (HMS), United States; Department of Anesthesia, Critical Care and Pain Medicine, BCH, HMS, Boston, MA, United States; Departments of Psychiatry and Radiology, MGH, Boston, MA, United States.
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19
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Bukhari Q, Borsook D, Rudin M, Becerra L. Random Forest Segregation of Drug Responses May Define Regions of Biological Significance. Front Comput Neurosci 2016; 10:21. [PMID: 27014046 PMCID: PMC4783407 DOI: 10.3389/fncom.2016.00021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Accepted: 02/23/2016] [Indexed: 12/02/2022] Open
Abstract
The ability to assess brain responses in unsupervised manner based on fMRI measure has remained a challenge. Here we have applied the Random Forest (RF) method to detect differences in the pharmacological MRI (phMRI) response in rats to treatment with an analgesic drug (buprenorphine) as compared to control (saline). Three groups of animals were studied: two groups treated with different doses of the opioid buprenorphine, low (LD), and high dose (HD), and one receiving saline. PhMRI responses were evaluated in 45 brain regions and RF analysis was applied to allocate rats to the individual treatment groups. RF analysis was able to identify drug effects based on differential phMRI responses in the hippocampus, amygdala, nucleus accumbens, superior colliculus, and the lateral and posterior thalamus for drug vs. saline. These structures have high levels of mu opioid receptors. In addition these regions are involved in aversive signaling, which is inhibited by mu opioids. The results demonstrate that buprenorphine mediated phMRI responses comprise characteristic features that allow a supervised differentiation from placebo treated rats as well as the proper allocation to the respective drug dose group using the RF method, a method that has been successfully applied in clinical studies.
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Affiliation(s)
- Qasim Bukhari
- Institute for Biomedical Engineering, ETH Zürich and University of ZürichZürich, Switzerland
| | - David Borsook
- Pain and Analgesia Imaging Neuroscience Group, Departments of Anesthesia, Perioperative and Pain Medicine, Boston Children's HospitalWaltham, MA, USA
- Department of Radiology, Boston Children's HospitalWaltham, MA, USA
| | - Markus Rudin
- Institute for Biomedical Engineering, ETH Zürich and University of ZürichZürich, Switzerland
- Institute of Pharmacology and Toxicology, University of ZürichZürich, Switzerland
| | - Lino Becerra
- Pain and Analgesia Imaging Neuroscience Group, Departments of Anesthesia, Perioperative and Pain Medicine, Boston Children's HospitalWaltham, MA, USA
- Department of Radiology, Boston Children's HospitalWaltham, MA, USA
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20
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Abstract
Migraine is a disease that contributes to major disability. Perhaps because migraine attacks are not immediately life-threatening per se and individuals return to a "normal" state between attacks, it is not taken seriously. However, migraine is associated with a number of comorbidities, including psychiatric disease, stroke, and other chronic pain disorders. Current acute treatments for episodic migraine are relatively effective, but preventive treatments for episodic and chronic migraine are far less so. Recent functional imaging studies have shown that the disease affects brain function and structure (either as a result of its genetic predisposition or as a result of repeated attacks). The current evidence in the pain field is that changes observed in brain function and structure may be reversible, adding credence to the notion that treating the disease aggressively and early may be beneficial to patients. Here we suggest a change in our approach to a disease that is currently not treated with the urgency that it deserves given its global prevalence, disease burden, and effects on brain function.
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Affiliation(s)
- David Borsook
- Center for Pain and the Brain (DB), Boston Children's and Massachusetts General Hospitals, Harvard Medical School; Department of Anesthesia, Critical Care and Pain Medicine (DB), Boston Children's Hospital; and Department of Neurology (DWD), Mayo Clinic, Phoenix, AZ
| | - David W Dodick
- Center for Pain and the Brain (DB), Boston Children's and Massachusetts General Hospitals, Harvard Medical School; Department of Anesthesia, Critical Care and Pain Medicine (DB), Boston Children's Hospital; and Department of Neurology (DWD), Mayo Clinic, Phoenix, AZ
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21
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Hargreaves RJ, Hoppin J, Sevigny J, Patel S, Chiao P, Klimas M, Verma A. Optimizing Central Nervous System Drug Development Using Molecular Imaging. Clin Pharmacol Ther 2015; 98:47-60. [PMID: 25869938 DOI: 10.1002/cpt.132] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Accepted: 04/07/2015] [Indexed: 12/12/2022]
Abstract
Advances in multimodality fusion imaging technologies promise to accelerate the understanding of the systems biology of disease and help in the development of new therapeutics. The use of molecular imaging biomarkers has been proven to shorten cycle times for central nervous system (CNS) drug development and thereby increase the efficiency and return on investment from research. Imaging biomarkers can be used to help select the molecules, doses, and patients most likely to test therapeutic hypotheses by stopping those that have little chance of success and accelerating those with potential to achieve beneficial clinical outcomes. CNS imaging biomarkers have the potential to drive new medical care practices for patients in the latent phases of progressive neurodegenerative disorders by enabling the detection, preventative treatment, and tracking of disease in a paradigm shift from today's approaches that have to see the overt symptoms of disease before treating it.
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Affiliation(s)
| | - J Hoppin
- inviCRO, LLC, Boston, Massachusetts, USA
| | - J Sevigny
- Biogen, Cambridge, Massachusetts, USA
| | - S Patel
- Biogen, Cambridge, Massachusetts, USA
| | - P Chiao
- Biogen, Cambridge, Massachusetts, USA
| | - M Klimas
- Merck Research Laboratories, West Point, Pennsylvania, USA
| | - A Verma
- Biogen, Cambridge, Massachusetts, USA
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22
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Millan MJ, Goodwin GM, Meyer-Lindenberg A, Ove Ögren S. Learning from the past and looking to the future: Emerging perspectives for improving the treatment of psychiatric disorders. Eur Neuropsychopharmacol 2015; 25:599-656. [PMID: 25836356 DOI: 10.1016/j.euroneuro.2015.01.016] [Citation(s) in RCA: 101] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Accepted: 01/28/2015] [Indexed: 02/06/2023]
Abstract
Modern neuropsychopharmacology commenced in the 1950s with the serendipitous discovery of first-generation antipsychotics and antidepressants which were therapeutically effective yet had marked adverse effects. Today, a broader palette of safer and better-tolerated agents is available for helping people that suffer from schizophrenia, depression and other psychiatric disorders, while complementary approaches like psychotherapy also have important roles to play in their treatment, both alone and in association with medication. Nonetheless, despite considerable efforts, current management is still only partially effective, and highly-prevalent psychiatric disorders of the brain continue to represent a huge personal and socio-economic burden. The lack of success in discovering more effective pharmacotherapy has contributed, together with many other factors, to a relative disengagement by pharmaceutical firms from neuropsychiatry. Nonetheless, interest remains high, and partnerships are proliferating with academic centres which are increasingly integrating drug discovery and translational research into their traditional activities. This is, then, a time of transition and an opportune moment to thoroughly survey the field. Accordingly, the present paper, first, chronicles the discovery and development of psychotropic agents, focusing in particular on their mechanisms of action and therapeutic utility, and how problems faced were eventually overcome. Second, it discusses the lessons learned from past successes and failures, and how they are being applied to promote future progress. Third, it comprehensively surveys emerging strategies that are (1), improving our understanding of the diagnosis and classification of psychiatric disorders; (2), deepening knowledge of their underlying risk factors and pathophysiological substrates; (3), refining cellular and animal models for discovery and validation of novel therapeutic agents; (4), improving the design and outcome of clinical trials; (5), moving towards reliable biomarkers of patient subpopulations and medication efficacy and (6), promoting collaborative approaches to innovation by uniting key partners from the regulators, industry and academia to patients. Notwithstanding the challenges ahead, the many changes and ideas articulated herein provide new hope and something of a framework for progress towards the improved prevention and relief of psychiatric and other CNS disorders, an urgent mission for our Century.
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Affiliation(s)
- Mark J Millan
- Pole for Innovation in Neurosciences, IDR Servier, 125 chemin de ronde, 78290 Croissy sur Seine, France.
| | - Guy M Goodwin
- University Department of Psychiatry, Oxford University, Warneford Hospital, Oxford OX3 7JX, England, UK
| | - Andreas Meyer-Lindenberg
- Central Institute of Mental Health, University of Heidelberg/Medical Faculty Mannheim, J5, D-68159 Mannheim, Germany
| | - Sven Ove Ögren
- Department of Neuroscience, Karolinska Institutet, Retzius väg 8, S-17177 Stockholm, Sweden
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23
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Liachenko S, Ramu J, Konak T, Paule MG, Hanig J. Quantitative Assessment of MRI T2 Response to Kainic Acid Neurotoxicity in Rats in vivo. Toxicol Sci 2015; 146:183-91. [PMID: 25904105 DOI: 10.1093/toxsci/kfv083] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The aim of this study was to assess quantitative changes in T2 relaxation using magnetic resonance imaging approaches in rats exposed to kainic acid to assess the utility of such endpoints as biomarkers of neurotoxicity. Quantitative T2 mapping was performed in 21 rats before and 2, 24, and 48 h after a single ip injection of 10 mg/kg of kainic acid. Three methods of quantifying T2 changes were explored: (1) Thresholding: all voxels exhibiting T2 ≤ 72 ms were designated normal tissue, whereas voxels exhibiting T2 > 72 ms were designated as lesioned tissue; (2) Statistical mapping: T2 maps obtained after treatment were statistically compared with averaged "baseline" maps, voxel-by-voxel; (3) Within-subject difference from baseline: for each individual the baseline T2 map was subtracted from the T2 map obtained after treatment. Based on the follow-up histopathological response there were 9 responders, 7 nonresponders, and 5 animals were not classified due to early sacrifice at 2 h which was too soon after treatment to detect any morphological evidence. The "thresholding" method (1) detected differences between groups only at the later time point of 48 h, the "statistical mapping" approach (2) detected differences 24 and 48 h after treatment, and the "within-subject difference from baseline" method (3) detected statistically significant differences between groups at each time point (2, 24, and 48 h). T2 mapping provides an easily quantifiable biomarker and the quantification method employing the use of the same animal as its own control provides the most sensitive metrics.
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Affiliation(s)
- Serguei Liachenko
- *Division of Neurotoxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas and Office of Testing and Research, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, White Oak, Maryland
| | - Jaivijay Ramu
- *Division of Neurotoxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas and Office of Testing and Research, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, White Oak, Maryland
| | - Tetyana Konak
- *Division of Neurotoxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas and Office of Testing and Research, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, White Oak, Maryland
| | - Merle G Paule
- *Division of Neurotoxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas and Office of Testing and Research, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, White Oak, Maryland
| | - Joseph Hanig
- *Division of Neurotoxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas and Office of Testing and Research, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, White Oak, Maryland
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Borsook D, Hargreaves R, Bountra C, Porreca F. Lost but making progress--Where will new analgesic drugs come from? Sci Transl Med 2015; 6:249sr3. [PMID: 25122640 DOI: 10.1126/scitranslmed.3008320] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
There is a critical need for effective new pharmacotherapies for pain. The paucity of new drugs successfully reaching the clinic calls for a reassessment of current analgesic drug discovery approaches. Many points early in the discovery process present significant hurdles, making it critical to exploit advances in pain neurobiology to increase the probability of success. In this review, we highlight approaches that are being pursued vigorously by the pain community for drug discovery, including innovative preclinical pain models, insights from genetics, mechanistic phenotyping of pain patients, development of biomarkers, and emerging insights into chronic pain as a disorder of both the periphery and the brain. Collaborative efforts between pharmaceutical, academic, and public entities to advance research in these areas promise to de-risk potential targets, stimulate investment, and speed evaluation and development of better pain therapies.
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Affiliation(s)
- David Borsook
- Center for Pain and the Brain, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Richard Hargreaves
- Center for Pain and the Brain, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Chas Bountra
- Department of Clinical Medicine, University of Oxford, Oxford OX1 2JD, UK
| | - Frank Porreca
- Center for Pain and the Brain and Department of Pharmacology, University of Arizona, Tucson, AZ 85724, USA.
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25
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Günther L, Beck R, Xiong G, Potschka H, Jahn K, Bartenstein P, Brandt T, Dutia M, Dieterich M, Strupp M, la Fougère C, Zwergal A. N-acetyl-L-leucine accelerates vestibular compensation after unilateral labyrinthectomy by action in the cerebellum and thalamus. PLoS One 2015; 10:e0120891. [PMID: 25803613 PMCID: PMC4372420 DOI: 10.1371/journal.pone.0120891] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Accepted: 01/27/2015] [Indexed: 11/18/2022] Open
Abstract
An acute unilateral vestibular lesion leads to a vestibular tone imbalance with nystagmus, head roll tilt and postural imbalance. These deficits gradually decrease over days to weeks due to central vestibular compensation (VC). This study investigated the effects of i.v. N-acetyl-DL-leucine, N-acetyl-L-leucine and N-acetyl-D-leucine on VC using behavioural testing and serial [18F]-Fluoro-desoxyglucose ([18F]-FDG)-μPET in a rat model of unilateral chemical labyrinthectomy (UL). Vestibular behavioural testing included measurements of nystagmus, head roll tilt and postural imbalance as well as sequential whole-brain [18F]-FDG-μPET was done before and on days 1,3,7 and 15 after UL. A significant reduction of postural imbalance scores was identified on day 7 in the N-acetyl-DL-leucine (p < 0.03) and the N-acetyl-L-leucine groups (p < 0.01), compared to the sham treatment group, but not in the N-acetyl-D-leucine group (comparison for applied dose of 24 mg i.v. per rat, equivalent to 60 mg/kg body weight, in each group). The course of postural compensation in the DL- and L-group was accelerated by about 6 days relative to controls. The effect of N-acetyl-L-leucine on postural compensation depended on the dose: in contrast to 60 mg/kg, doses of 15 mg/kg and 3.75 mg/kg had no significant effect. N-acetyl-L-leucine did not change the compensation of nystagmus or head roll tilt at any dose. Measurements of the regional cerebral glucose metabolism (rCGM) by means of μPET revealed that only N-acetyl-L-leucine but not N-acetyl-D-leucine caused a significant increase of rCGM in the vestibulocerebellum and a decrease in the posterolateral thalamus and subthalamic region on days 3 and 7. A similar pattern was found when comparing the effect of N-acetyl-L-leucine on rCGM in an UL-group and a sham UL-group without vestibular damage. In conclusion, N-acetyl-L-leucine improves compensation of postural symptoms after UL in a dose-dependent and specific manner, most likely by activating the vestibulocerebellum and deactivating the posterolateral thalamus.
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Affiliation(s)
- Lisa Günther
- German Center for Vertigo and Balance Disorders, DSGZ, Ludwig-Maximilians-University of Munich, Munich, Germany
| | - Roswitha Beck
- German Center for Vertigo and Balance Disorders, DSGZ, Ludwig-Maximilians-University of Munich, Munich, Germany
| | - Guoming Xiong
- German Center for Vertigo and Balance Disorders, DSGZ, Ludwig-Maximilians-University of Munich, Munich, Germany
| | - Heidrun Potschka
- German Center for Vertigo and Balance Disorders, DSGZ, Ludwig-Maximilians-University of Munich, Munich, Germany; Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig-Maximilians-University of Munich, Munich, Germany
| | - Klaus Jahn
- German Center for Vertigo and Balance Disorders, DSGZ, Ludwig-Maximilians-University of Munich, Munich, Germany; Department of Neurology, Ludwig-Maximilians-University of Munich, Munich, Germany
| | - Peter Bartenstein
- German Center for Vertigo and Balance Disorders, DSGZ, Ludwig-Maximilians-University of Munich, Munich, Germany; Department of Nuclear Medicine, Ludwig-Maximilians-University of Munich, Munich, Germany
| | - Thomas Brandt
- German Center for Vertigo and Balance Disorders, DSGZ, Ludwig-Maximilians-University of Munich, Munich, Germany; Clinical Neuroscience, Ludwig-Maximilians-University of Munich, Munich, Germany
| | - Mayank Dutia
- Center for Integrative Physiology, University of Edinburgh, Edinburgh, Scotland
| | - Marianne Dieterich
- German Center for Vertigo and Balance Disorders, DSGZ, Ludwig-Maximilians-University of Munich, Munich, Germany; Department of Neurology, Ludwig-Maximilians-University of Munich, Munich, Germany
| | - Michael Strupp
- German Center for Vertigo and Balance Disorders, DSGZ, Ludwig-Maximilians-University of Munich, Munich, Germany; Department of Neurology, Ludwig-Maximilians-University of Munich, Munich, Germany
| | - Christian la Fougère
- German Center for Vertigo and Balance Disorders, DSGZ, Ludwig-Maximilians-University of Munich, Munich, Germany; Department of Nuclear Medicine, Ludwig-Maximilians-University of Munich, Munich, Germany; Department of Nuclear Medicine, Eberhard Karls University of Tübingen, Tübingen, Germany
| | - Andreas Zwergal
- German Center for Vertigo and Balance Disorders, DSGZ, Ludwig-Maximilians-University of Munich, Munich, Germany; Department of Neurology, Ludwig-Maximilians-University of Munich, Munich, Germany
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Abstract
Imaging has played an important part in the diagnosis of disease and development of the understanding of the underlying disease mechanisms and is now poised to make an impact in the development of new pharmaceuticals. This chapter discusses the underlying technologies that make the field ready for this challenge. In particular, the potentials of magnetic resonance imaging and functional magnetic resonance imaging are outlined, including the new methods developed to provide additional information from the scans carried out. The field of nuclear medicine has seen a rapid increase in interest as advances in radiochemistry have enabled a wide range of new radiotracers to be synthesised.
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Affiliation(s)
- James Nairne
- GE Healthcare, The Grove Centre, Amersham, Buckinghamshire, United Kingdom
| | - Peter B Iveson
- GE Healthcare, The Grove Centre, Amersham, Buckinghamshire, United Kingdom
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27
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Damiano CR, Mazefsky CA, White SW, Dichter GS. Future directions for research in autism spectrum disorders. JOURNAL OF CLINICAL CHILD AND ADOLESCENT PSYCHOLOGY : THE OFFICIAL JOURNAL FOR THE SOCIETY OF CLINICAL CHILD AND ADOLESCENT PSYCHOLOGY, AMERICAN PSYCHOLOGICAL ASSOCIATION, DIVISION 53 2014; 43:828-43. [PMID: 25216048 PMCID: PMC4163956 DOI: 10.1080/15374416.2014.945214] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
This article suggests future directions for research aimed at improving our understanding of the etiology and pathophysiology of autism spectrum disorder (ASD) as well as pharmacologic and psychosocial interventions for ASD across the lifespan. The past few years have witnessed unprecedented transformations in the understanding of ASD neurobiology, genetics, early identification, and early intervention. However, recent increases in ASD prevalence estimates highlight the urgent need for continued efforts to translate novel ASD discoveries into effective interventions for all individuals with ASD. In this article we highlight promising areas for ongoing and new research expected to quicken the pace of scientific discovery and ultimately the translation of research findings into accessible and empirically supported interventions for those with ASD. We highlight emerging research in the following domains as particularly promising and pressing: (a) preclinical models, (b) experimental therapeutics, (c) early identification and intervention, (d) psychiatric comorbidities and the Research Domain Criteria initiative, (e) ecological momentary assessment, (f) neurotechnologies, and (g) the needs of adults with ASD. Increased research emphasis in these areas has the potential to hasten the translation of knowledge on the etiological mechanisms of ASD to psychosocial and biological interventions to reduce the burden of ASD on affected individuals and their families.
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Affiliation(s)
- Cara R. Damiano
- Department of Psychology, University of North Carolina, Chapel Hill, NC
- Carolina Institute for Developmental Disabilities, University of North Carolina, Chapel Hill, NC
| | - Carla A. Mazefsky
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Susan W. White
- Department of Psychology, Virginia Polytechnic Institute and State University, Blacksburg, VA
| | - Gabriel S. Dichter
- Department of Psychology, University of North Carolina, Chapel Hill, NC
- Department of Psychiatry, University of North Carolina, Chapel Hill, NC
- Carolina Institute for Developmental Disabilities, University of North Carolina, Chapel Hill, NC
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Hargreaves RJ, Rabiner EA. Translational PET imaging research. Neurobiol Dis 2013; 61:32-8. [PMID: 24055214 DOI: 10.1016/j.nbd.2013.08.017] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2013] [Revised: 08/07/2013] [Accepted: 08/14/2013] [Indexed: 10/26/2022] Open
Abstract
The goal of any early central nervous system (CNS) drug development program is always to test the mechanism and not the molecule in order to support additional research investments in late phase clinical trials. Confirmation that drugs reach their targets using translational positron emission tomography (PET) imaging markers of engagement is central to successful clinical proof-of-concept testing and has become an important feature of most neuropsychiatric drug development programs. CNS PET imaging can also play an important role in the clinical investigation of the neuropharmacological basis of psychiatric disease and the optimization of drug therapy.
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Affiliation(s)
- Richard J Hargreaves
- Merck and Co, WP-42-212, 770, Sumneytown Pike, PO Box 4, West Point, PA19486, USA.
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Bruehl S, Apkarian AV, Ballantyne JC, Berger A, Borsook D, Chen WG, Farrar JT, Haythornthwaite JA, Horn SD, Iadarola MJ, Inturrisi CE, Lao L, Mackey S, Mao J, Sawczuk A, Uhl GR, Witter J, Woolf CJ, Zubieta JK, Lin Y. Personalized medicine and opioid analgesic prescribing for chronic pain: opportunities and challenges. THE JOURNAL OF PAIN 2013; 14:103-13. [PMID: 23374939 DOI: 10.1016/j.jpain.2012.10.016] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2012] [Revised: 10/17/2012] [Accepted: 10/25/2012] [Indexed: 01/05/2023]
Abstract
UNLABELLED Use of opioid analgesics for pain management has increased dramatically over the past decade, with corresponding increases in negative sequelae including overdose and death. There is currently no well-validated objective means of accurately identifying patients likely to experience good analgesia with low side effects and abuse risk prior to initiating opioid therapy. This paper discusses the concept of data-based personalized prescribing of opioid analgesics as a means to achieve this goal. Strengths, weaknesses, and potential synergism of traditional randomized placebo-controlled trial (RCT) and practice-based evidence (PBE) methodologies as means to acquire the clinical data necessary to develop validated personalized analgesic-prescribing algorithms are overviewed. Several predictive factors that might be incorporated into such algorithms are briefly discussed, including genetic factors, differences in brain structure and function, differences in neurotransmitter pathways, and patient phenotypic variables such as negative affect, sex, and pain sensitivity. Currently available research is insufficient to inform development of quantitative analgesic-prescribing algorithms. However, responder subtype analyses made practical by the large numbers of chronic pain patients in proposed collaborative PBE pain registries, in conjunction with follow-up validation RCTs, may eventually permit development of clinically useful analgesic-prescribing algorithms. PERSPECTIVE Current research is insufficient to base opioid analgesic prescribing on patient characteristics. Collaborative PBE studies in large, diverse pain patient samples in conjunction with follow-up RCTs may permit development of quantitative analgesic-prescribing algorithms that could optimize opioid analgesic effectiveness and mitigate risks of opioid-related abuse and mortality.
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Affiliation(s)
- Stephen Bruehl
- Department of Anesthesiology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA.
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Abstract
Nerve damage takes place during surgery. As a consequence, significant numbers (10%-40%) of patients experience chronic neuropathic pain termed surgically induced neuropathic pain (SNPP). The initiating surgery and nerve damage set off a cascade of events that includes both pain and an inflammatory response, resulting in "peripheral and central sensitization," with the latter resulting from repeated barrages of neural activity from nociceptors. In affected patients, these initial events produce chemical, structural, and functional changes in the peripheral and central nervous systems (CNS). The maladaptive changes in damaged nerves lead to peripheral manifestations of the neuropathic state-allodynia, sensory loss, shooting pains, etc, that can manifest long after the effects of the surgical injury have resolved. The CNS manifestations that occur are termed "centralization of pain" and affect sensory, emotional, and other (eg, cognitive) systems as well as contributing to some of the manifestations of the chronic pain syndrome (eg, depression). Currently there are no objective measures of nociception and pain in the perioperative period. As such, intermittent or continuous pain may take place during and after surgery. New technologies including direct measures of specific brain function of nociception and new insights into preoperative evaluation of patients including genetic predisposition, appear to provide initial opportunities for decreasing the burden of SNPP, until treatments with high efficacy and low adverse effects that either prevent or treat pain are discovered.
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Abstract
This community page describes the database and associated Web application that comprise the Allen Human Brain Atlas, an open online resource that integrates genomic and anatomic human brain data.
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Khalili-Mahani N, van Osch MJ, de Rooij M, Beckmann CF, van Buchem MA, Dahan A, van Gerven JM, Rombouts SARB. Spatial heterogeneity of the relation between resting-state connectivity and blood flow: an important consideration for pharmacological studies. Hum Brain Mapp 2012; 35:929-42. [PMID: 23281174 DOI: 10.1002/hbm.22224] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2012] [Revised: 10/08/2012] [Accepted: 10/22/2012] [Indexed: 01/28/2023] Open
Abstract
Resting state fMRI (RSfMRI) and arterial spin labeling (ASL) provide the field of pharmacological Neuroimaging tool for investigating states of brain activity in terms of functional connectivity or cerebral blood flow (CBF). Functional connectivity reflects the degree of synchrony or correlation of spontaneous fluctuations--mostly in the blood oxygen level dependent (BOLD) signal--across brain networks; but CBF reflects mean delivery of arterial blood to the brain tissue over time. The BOLD and CBF signals are linked to common neurovascular and hemodynamic mechanisms that necessitate increased oxygen transportation to the site of neuronal activation; however, the scale and the sources of variation in static CBF and spatiotemporal BOLD correlations are likely different. We tested this hypothesis by examining the relation between CBF and resting-state-network consistency (RSNC)--representing average intranetwork connectivity, determined from dual regression analysis with eight standard networks of interest (NOIs)--in a crossover placebo-controlled study of morphine and alcohol. Overall, we observed spatially heterogeneous relations between RSNC and CBF, and between the experimental factors (drug-by-time, time, drug and physiological rates) and each of these metrics. The drug-by-time effects on CBF were significant in all networks, but significant RSNC changes were limited to the sensorimotor, the executive/salience and the working memory networks. The post-hoc voxel-wise statistics revealed similar dissociations, perhaps suggesting differential sensitivity of RSNC and CBF to neuronal and vascular endpoints of drug actions. The spatial heterogeneity of RSNC/CBF relations encourages further investigation into the role of neuroreceptor distribution and cerebrovascular anatomy in predicting spontaneous fluctuations under drugs.
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Affiliation(s)
- Najmeh Khalili-Mahani
- Institute of Psychology, Leiden University, Leiden, The Netherlands; Department of Radiology, Leiden University Medical Center (LUMC), Leiden, The Netherlands; Leiden Institute for Brain and Cognition (LIBC), Leiden University, Leiden, The Netherlands
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Abstract
PURPOSE OF REVIEW This review summarizes key findings of the current literature on functional neuroimaging in migraine and describes how these studies have changed our view of the disorder. RECENT FINDINGS Recent studies have started not only to investigate the global cerebral activation pattern during migraine attacks, but to address specific aspects of migraine attacks such as photophobia, osmophobia as well as pain perception with the aim of disentangling the underlying mechanisms. There is also more and more evidence that the migraine brain is abnormal even outside of attacks and that repeated attacks are leading to functional and structural alterations in the brain, which may in turn drive the transformation of migraine to its chronic form. Some new results are pinpointing toward a potential role of interesting new brain areas in migraine pathophysiology such as the temporal cortex or the basal ganglia. SUMMARY Neuroimaging studies are beginning to shed light on the mechanisms underlying the development and evolution of migraine and its specific symptoms. Future studies have the potential to also improve our understanding of established and upcoming treatment approaches and to monitor treatment effects in an objective and noninvasive way.
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Opioid glycopeptide analgesics derived from endogenous enkephalins and endorphins. Future Med Chem 2012; 4:205-26. [PMID: 22300099 DOI: 10.4155/fmc.11.195] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Over the past two decades, potent and selective analgesics have been developed from endogenous opioid peptides. Glycosylation provides an important means of modulating interaction with biological membranes, which greatly affects the pharmacodynamics and pharmacokinetics of the resulting glycopeptide analogues. Furthermore, manipulation of the membrane affinity allows penetration of cellular barriers that block efficient drug distribution, including the blood-brain barrier. Extremely potent and selective opiate agonists have been developed from endogenous peptides, some of which show great promise as drug candidates.
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Borsook D. ‘Hot Feet – Hot Brain’: Gene and brain dysfunction in erythromelalgia. Pain 2012; 153:945-947. [DOI: 10.1016/j.pain.2012.02.029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2012] [Revised: 02/24/2012] [Accepted: 02/24/2012] [Indexed: 12/17/2022]
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Pharmacologic magnetic resonance imaging (phMRI): imaging drug action in the brain. Neuroimage 2012; 62:1072-85. [PMID: 22495143 DOI: 10.1016/j.neuroimage.2012.03.075] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2012] [Accepted: 03/23/2012] [Indexed: 02/01/2023] Open
Abstract
The technique of functional magnetic resonance (fMRI), using various cognitive, motor and sensory stimuli has led to a revolution in the ability to map brain function. Drugs can also be used as stimuli to elicit an hemodynamic change. Stimulation with a pharmaceutical has a number of very different consequences compared to user controllable stimuli, most importantly in the time course of stimulus and response that is not, in general, controllable by the experimenter. Therefore, this type of experiment has been termed pharmacologic MRI (phMRI). The use of a drug stimulus leads to a number of interesting possibilities compared to conventional fMRI. Using receptor specific ligands one can characterize brain circuitry specific to neurotransmitter systems. The possibility exists to measure parameters reflecting neurotransmitter release and binding associated with the pharmacokinetics and/or the pharmacodynamics of drugs. There is also the ability to measure up- and down-regulation of receptors in specific disease states. phMRI can be characterized as a molecular imaging technique using the natural hemodynamic transduction related to neuro-receptor stimulus. This provides a coupling mechanism with very high sensitivity that can rival positron emission tomography (PET) in some circumstances. The large numbers of molecules available, that do not require a radio-label, means that phMRI becomes a very useful tool for performing drug discovery. Data and arguments will be presented to show that phMRI can provide information on neuro-receptor signaling and function that complements the static picture generated by PET studies of receptor numbers and occupancies.
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