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Melo-Carrillo A, Strassman AM, Broide R, Adams A, Dabruzzo B, Brin M, Burstein R. Novel insight into atogepant mechanisms of action in migraine prevention. Brain 2024; 147:2884-2896. [PMID: 38411458 PMCID: PMC11292906 DOI: 10.1093/brain/awae062] [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: 11/30/2023] [Revised: 01/16/2024] [Accepted: 01/24/2024] [Indexed: 02/28/2024] Open
Abstract
Recently, we showed that while atogepant-a small-molecule calcitonin gene-related peptide (CGRP) receptor antagonist-does not fully prevent activation of meningeal nociceptors, it significantly reduces a cortical spreading depression (CSD)-induced early response probability in C fibres and late response probability in Aδ fibres. The current study investigates atogepant effect on CSD-induced activation and sensitization of high threshold (HT) and wide dynamic range (WDR) central dura-sensitive trigeminovascular neurons. In anaesthetized male rats, single-unit recordings were used to assess effects of atogepant (5 mg/kg) versus vehicle on CSD-induced activation and sensitization of HT and WDR trigeminovascular neurons. Single cell analysis of atogepant pretreatment effects on CSD-induced activation and sensitization of central trigeminovascular neurons in the spinal trigeminal nucleus revealed the ability of this small molecule CGRP receptor antagonist to prevent activation and sensitization of nearly all HT neurons (8/10 versus 1/10 activated neurons in the control versus treated groups, P = 0.005). In contrast, atogepant pretreatment effects on CSD-induced activation and sensitization of WDR neurons revealed an overall inability to prevent their activation (7/10 versus 5/10 activated neurons in the control versus treated groups, P = 0.64). Unexpectedly however, in spite of atogepant's inability to prevent activation of WDR neurons, it prevented their sensitization (as reflected their responses to mechanical stimulation of the facial receptive field before and after the CSD). Atogepant' ability to prevent activation and sensitization of HT neurons is attributed to its preferential inhibitory effects on thinly myelinated Aδ fibres. Atogepant's inability to prevent activation of WDR neurons is attributed to its lesser inhibitory effects on the unmyelinated C fibres. Molecular and physiological processes that govern neuronal activation versus sensitization can explain how reduction in CGRP-mediated slow but not glutamate-mediated fast synaptic transmission between central branches of meningeal nociceptors and nociceptive neurons in the spinal trigeminal nucleus can prevent their sensitization but not activation.
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Affiliation(s)
- Agustin Melo-Carrillo
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center. Boston, MA 02115, USA
- Harvard Medical School, Harvard University, Boston, MA 02115, USA
| | - Andrew M Strassman
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center. Boston, MA 02115, USA
- Harvard Medical School, Harvard University, Boston, MA 02115, USA
| | - Ron Broide
- Allergan, an Abbvie Company, Irvine, CA 92612, USA
| | - Aubrey Adams
- Allergan, an Abbvie Company, Irvine, CA 92612, USA
| | | | - Mitchell Brin
- Allergan, an Abbvie Company, Irvine, CA 92612, USA
- Department of Neurology, University of California, Irvine, CA 92697USA
| | - Rami Burstein
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center. Boston, MA 02115, USA
- Harvard Medical School, Harvard University, Boston, MA 02115, USA
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Al-Omari A, Gaszner B, Zelena D, Gecse K, Berta G, Biró-Sütő T, Szocsics P, Maglóczky Z, Gombás P, Pintér E, Juhász G, Kormos V. Neuroanatomical evidence and a mouse calcitonin gene-related peptide model in line with human functional magnetic resonance imaging data support the involvement of peptidergic Edinger-Westphal nucleus in migraine. Pain 2024:00006396-990000000-00627. [PMID: 38875125 DOI: 10.1097/j.pain.0000000000003294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2023] [Accepted: 05/02/2024] [Indexed: 06/16/2024]
Abstract
ABSTRACT The urocortin 1 (UCN1)-expressing centrally projecting Edinger-Westphal (EWcp) nucleus is influenced by circadian rhythms, hormones, stress, and pain, all known migraine triggers. Our study investigated EWcp's potential involvement in migraine. Using RNAscope in situ hybridization and immunostaining, we examined the expression of calcitonin gene-related peptide (CGRP) receptor components in both mouse and human EWcp and dorsal raphe nucleus (DRN). Tracing study examined connection between EWcp and the spinal trigeminal nucleus (STN). The intraperitoneal CGRP injection model of migraine was applied and validated by light-dark box, and von Frey assays in mice, in situ hybridization combined with immunostaining, were used to assess the functional-morphological changes. The functional connectivity matrix of EW was examined using functional magnetic resonance imaging in control humans and interictal migraineurs. We proved the expression of CGRP receptor components in both murine and human DRN and EWcp. We identified a direct urocortinergic projection from EWcp to the STN. Photophobic behavior, periorbital hyperalgesia, increased c-fos gene-encoded protein immunoreactivity in the lateral periaqueductal gray matter and trigeminal ganglia, and phosphorylated c-AMP-responsive element binding protein in the STN supported the efficacy of CGRP-induced migraine-like state. Calcitonin gene-related peptide administration also increased c-fos gene-encoded protein expression, Ucn1 mRNA, and peptide content in EWcp/UCN1 neurons while reducing serotonin and tryptophan hydroxylase-2 levels in the DRN. Targeted ablation of EWcp/UCN1 neurons induced hyperalgesia. A positive functional connectivity between EW and STN as well as DRN has been identified by functional magnetic resonance imaging. The presented data strongly suggest the regulatory role of EWcp/UCN1 neurons in migraine through the STN and DRN with high translational value.
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Affiliation(s)
- Ammar Al-Omari
- Department of Pharmacology and Pharmacotherapy, Medical School, University of Pécs, Pécs, Hungary
| | - Balázs Gaszner
- Department of Anatomy, Medical School and Research Group for Mood Disorders, Centre for Neuroscience, University of Pécs, Pécs, Hungary
| | - Dóra Zelena
- Institute of Physiology, Medical School, University of Pécs, Pécs, Hungary
| | - Kinga Gecse
- Department of Pharmacodynamics, Faculty of Pharmaceutical Sciences, Semmelweis University, Budapest, Hungary
- NAP3.0-SE Neuropsychopharmacology Research Group, Hungarian Brain Research Program, Semmelweis University, Budapest, Hungary
| | - Gergely Berta
- Department of Medical Biology, Medical School, University of Pécs, Hungary
| | - Tünde Biró-Sütő
- Department of Pharmacology and Pharmacotherapy, Medical School, University of Pécs, Pécs, Hungary
| | - Péter Szocsics
- Human Brain Research Laboratory, HUN-REN Institute of Experimental Medicine, Budapest, Hungary
- Szentágothai János Doctoral School of Neuroscience, Semmelweis University, Budapest, Hungary
| | - Zsófia Maglóczky
- Human Brain Research Laboratory, HUN-REN Institute of Experimental Medicine, Budapest, Hungary
- Szentágothai János Doctoral School of Neuroscience, Semmelweis University, Budapest, Hungary
| | - Péter Gombás
- Department of Pathology, St. Borbála Hospital, Tatabánya, Hungary
| | - Erika Pintér
- Department of Pharmacology and Pharmacotherapy, Medical School, University of Pécs, Pécs, Hungary
| | - Gabriella Juhász
- Department of Pharmacodynamics, Faculty of Pharmaceutical Sciences, Semmelweis University, Budapest, Hungary
- NAP3.0-SE Neuropsychopharmacology Research Group, Hungarian Brain Research Program, Semmelweis University, Budapest, Hungary
| | - Viktória Kormos
- Department of Pharmacology and Pharmacotherapy, Medical School, University of Pécs, Pécs, Hungary
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Li H, Xu X, Xu R, Fan PX, Zhou J, Dong L. Latent class analysis of migraine associated vestibular-auditory symptoms. Cephalalgia 2024; 44:3331024241262488. [PMID: 38887813 DOI: 10.1177/03331024241262488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/20/2024]
Abstract
OBJECTIVE This study aimed to identify the potential subgroups of migraines based on the patterns of migraine associated symptoms, vestibular and auditory symptoms using latent class analysis and to explore their characteristics. METHOD A total of 555 patients with migraine participated in the study. Symptoms such as nausea, vomiting, photophobia, phonophobia, osmophobia, visual symptoms, vestibular symptoms (dizziness, vertigo), and auditory symptoms (tinnitus, hearing loss, aural fullness) were assessed. Latent class analysis was performed to identify subgroups of migraines. Covariates such as gender, age of migraine onset, frequency of migraine attacks per month, and family history were also considered. RESULTS The analysis revealed four latent classes: the Prominent Vestibular; Prominent Nausea; Presenting Symptoms but not prominent or dominant; and Sensory Hypersensitivity groups. Various covariates, such as gender, age of migraine onset, and frequency of migraine attacks, demonstrated significant differences among the four groups. The Sensory Hypersensitivity group showed the presence of multiple sensory symptoms, earlier age of migraine onset, and higher proportion of females. The Prominent Vestibular group had the highest probability of dizziness or vertigo but lacked the presence of auditory symptoms. The Prominent Nausea group exhibited prominent nausea. The Presenting Symptoms but not prominent or dominant group comprised individuals with the highest migraine attacks per month and proportion of chronic migraine. CONCLUSION This study identifies four subgroups of migraines based on the patterns of symptoms. The findings suggest potential different but overlapped mechanisms behind the vestibular and auditory symptoms of migraine. Considering the different patterns of migraine-related symptoms may provide deeper insights for patients' prognosis and clinical decision-making.
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Affiliation(s)
- Hui Li
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University Department of Neurology, Chongqing, China
| | - Xiaonuo Xu
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University Department of Neurology, Chongqing, China
| | - Rongjiang Xu
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University Department of Neurology, Chongqing, China
| | - Ping Xiao Fan
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University Department of Neurology, Chongqing, China
| | - Jiying Zhou
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University Department of Neurology, Chongqing, China
| | - Liang Dong
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University Department of Neurology, Chongqing, China
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Karsan N, Gosalia H, Goadsby PJ. Molecular Mechanisms of Migraine: Nitric Oxide Synthase and Neuropeptides. Int J Mol Sci 2023; 24:11993. [PMID: 37569369 PMCID: PMC10418996 DOI: 10.3390/ijms241511993] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 07/12/2023] [Accepted: 07/17/2023] [Indexed: 08/13/2023] Open
Abstract
Migraine is a common condition with disabling attacks that burdens people in the prime of their working lives. Despite years of research into migraine pathophysiology and therapeutics, much remains to be learned about the mechanisms at play in this complex neurovascular condition. Additionally, there remains a relative paucity of specific and targeted therapies available. Many sufferers remain underserved by currently available broad action preventive strategies, which are also complicated by poor tolerance and adverse effects. The development of preclinical migraine models in the laboratory, and the advances in human experimental migraine provocation, have led to the identification of key molecules likely involved in the molecular circuity of migraine, and have provided novel therapeutic targets. Importantly, the identification that vasoconstriction is neither necessary nor required for headache abortion has changed the landscape of migraine treatment and has broadened the therapy targets for patients with vascular risk factors or vascular disease. These targets include nitric oxide synthase (NOS) and several neuropeptides that are involved in migraine. The ability of NO donors and infusion of some of these peptides into humans to trigger typical migraine-like attacks has supported the development of targeted therapies against these molecules. Some of these, such as those targeting calcitonin gene-related peptide (CGRP), have already reached clinical practice and are displaying a positive outcome in migraineurs for the better by offering targeted efficacy without significant adverse effects. Others, such as those targeting pituitary adenylate cyclase activating polypeptide (PACAP), are showing promise and are likely to enter phase 3 clinical trials in the near future. Understanding these nitrergic and peptidergic mechanisms in migraine and their interactions is likely to lead to further therapeutic strategies for migraine in the future.
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Affiliation(s)
- Nazia Karsan
- Headache Group, NIHR King’s Clinical Research Facility and SLaM Biomedical Research Centre, The Wolfson Sensory, Pain and Regeneration Research Centre, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London SE5 9PJ, UK; (N.K.); (H.G.)
| | - Helin Gosalia
- Headache Group, NIHR King’s Clinical Research Facility and SLaM Biomedical Research Centre, The Wolfson Sensory, Pain and Regeneration Research Centre, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London SE5 9PJ, UK; (N.K.); (H.G.)
| | - Peter J. Goadsby
- Headache Group, NIHR King’s Clinical Research Facility and SLaM Biomedical Research Centre, The Wolfson Sensory, Pain and Regeneration Research Centre, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London SE5 9PJ, UK; (N.K.); (H.G.)
- Department of Neurology, University of California, Los Angeles, CA 90095, USA
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Hong JB, Lange KS, Overeem LH, Triller P, Raffaelli B, Reuter U. A Scoping Review and Meta-Analysis of Anti-CGRP Monoclonal Antibodies: Predicting Response. Pharmaceuticals (Basel) 2023; 16:934. [PMID: 37513846 PMCID: PMC10385131 DOI: 10.3390/ph16070934] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 06/15/2023] [Accepted: 06/23/2023] [Indexed: 07/30/2023] Open
Abstract
Calcitonin gene-related peptide-targeted monoclonal antibodies (CGRP mAbs) are increasingly being used as preventive treatments for migraine. Their effectiveness and safety were established through numerous randomized placebo-controlled trials and real-world studies, yet a significant proportion of patients do not respond to this treatment, and currently, there is a lack of accepted predictors of response to guide expectations, as data from studies so far are lacking and inconsistent. We searched Embase and MEDLINE databases for studies reporting on predictors of response to CGRP and/or CGRP-receptor (CGRP-R) mAbs, defined as a 30% or 50% reduction in monthly headache or migraine days at varying durations of follow-up. Quantitative synthesis was performed where applicable. We found 38 real-world studies that investigated the association between various predictors and response rates. Based on these studies, good response to triptans and unilateral pain with or without unilateral autonomic symptoms are predictors of a good response to CGRP(-R) mAbs. Conversely, obesity, interictal allodynia, the presence of daily headaches, a higher number of non-successful previous prophylactic medications, and psychiatric comorbidities including depression are predictive of a poor response to CGRP(-R) mAbs. Future studies should confirm these results and help to generate more tailored treatment strategies in patients with migraine.
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Affiliation(s)
- Ja Bin Hong
- Department of Neurology, Charité Universitätsmedizin Berlin, Corporate Member of Humboldt University and Free University Berlin, 10117 Berlin, Germany
| | - Kristin Sophie Lange
- Department of Neurology, Charité Universitätsmedizin Berlin, Corporate Member of Humboldt University and Free University Berlin, 10117 Berlin, Germany
| | - Lucas Hendrik Overeem
- Department of Neurology, Charité Universitätsmedizin Berlin, Corporate Member of Humboldt University and Free University Berlin, 10117 Berlin, Germany
- Doctoral Program, International Graduate Program Medical Neurosciences, Humboldt Graduate School, 10117 Berlin, Germany
| | - Paul Triller
- Department of Neurology, Charité Universitätsmedizin Berlin, Corporate Member of Humboldt University and Free University Berlin, 10117 Berlin, Germany
| | - Bianca Raffaelli
- Department of Neurology, Charité Universitätsmedizin Berlin, Corporate Member of Humboldt University and Free University Berlin, 10117 Berlin, Germany
- Clinician Scientist Program, Berlin Institute of Health at Charité (BIH), 10117 Berlin, Germany
| | - Uwe Reuter
- Department of Neurology, Charité Universitätsmedizin Berlin, Corporate Member of Humboldt University and Free University Berlin, 10117 Berlin, Germany
- Universitätsmedizin Greifswald, 17475 Greifswald, Germany
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Kuburas A, Russo AF. Shared and independent roles of CGRP and PACAP in migraine pathophysiology. J Headache Pain 2023; 24:34. [PMID: 37009867 PMCID: PMC10069045 DOI: 10.1186/s10194-023-01569-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 03/23/2023] [Indexed: 04/04/2023] Open
Abstract
The neuropeptides calcitonin gene-related peptide (CGRP) and pituitary adenylate cyclase-activating polypeptide (PACAP) have emerged as mediators of migraine pathogenesis. Both are vasodilatory peptides that can cause migraine-like attacks when infused into people and migraine-like symptoms when injected into rodents. In this narrative review, we compare the similarities and differences between the peptides in both their clinical and preclinical migraine actions. A notable clinical difference is that PACAP, but not CGRP, causes premonitory-like symptoms in patients. Both peptides are found in distinct, but overlapping areas relevant to migraine, most notably with the prevalence of CGRP in trigeminal ganglia and PACAP in sphenopalatine ganglia. In rodents, the two peptides share activities, including vasodilation, neurogenic inflammation, and nociception. Most strikingly, CGRP and PACAP cause similar migraine-like symptoms in rodents that are manifested as light aversion and tactile allodynia. Yet, the peptides appear to act by independent mechanisms possibly by distinct intracellular signaling pathways. The complexity of these signaling pathways is magnified by the existence of multiple CGRP and PACAP receptors that may contribute to migraine pathogenesis. Based on these differences, we suggest PACAP and its receptors provide a rich set of targets to complement and augment the current CGRP-based migraine therapeutics.
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Affiliation(s)
- Adisa Kuburas
- Department of Molecular Physiology and Biophysics and Department of Neurology, University of Iowa, Iowa City, IA, 52242, USA
| | - Andrew F Russo
- Department of Molecular Physiology and Biophysics and Department of Neurology, University of Iowa, Iowa City, IA, 52242, USA.
- Veterans Affairs Medical Center, Iowa City, IA, 52246, USA.
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Russo AF, Hay DL. CGRP physiology, pharmacology, and therapeutic targets: migraine and beyond. Physiol Rev 2023; 103:1565-1644. [PMID: 36454715 PMCID: PMC9988538 DOI: 10.1152/physrev.00059.2021] [Citation(s) in RCA: 63] [Impact Index Per Article: 63.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 11/23/2022] [Accepted: 11/27/2022] [Indexed: 12/03/2022] Open
Abstract
Calcitonin gene-related peptide (CGRP) is a neuropeptide with diverse physiological functions. Its two isoforms (α and β) are widely expressed throughout the body in sensory neurons as well as in other cell types, such as motor neurons and neuroendocrine cells. CGRP acts via at least two G protein-coupled receptors that form unusual complexes with receptor activity-modifying proteins. These are the CGRP receptor and the AMY1 receptor; in rodents, additional receptors come into play. Although CGRP is known to produce many effects, the precise molecular identity of the receptor(s) that mediates CGRP effects is seldom clear. Despite the many enigmas still in CGRP biology, therapeutics that target the CGRP axis to treat or prevent migraine are a bench-to-bedside success story. This review provides a contextual background on the regulation and sites of CGRP expression and CGRP receptor pharmacology. The physiological actions of CGRP in the nervous system are discussed, along with updates on CGRP actions in the cardiovascular, pulmonary, gastrointestinal, immune, hematopoietic, and reproductive systems and metabolic effects of CGRP in muscle and adipose tissues. We cover how CGRP in these systems is associated with disease states, most notably migraine. In this context, we discuss how CGRP actions in both the peripheral and central nervous systems provide a basis for therapeutic targeting of CGRP in migraine. Finally, we highlight potentially fertile ground for the development of additional therapeutics and combinatorial strategies that could be designed to modulate CGRP signaling for migraine and other diseases.
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Affiliation(s)
- Andrew F Russo
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, Iowa
- Department of Neurology, University of Iowa, Iowa City, Iowa
- Center for the Prevention and Treatment of Visual Loss, Department of Veterans Affairs Health Center, Iowa City, Iowa
| | - Debbie L Hay
- Department of Pharmacology and Toxicology, University of Otago, Dunedin, New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, School of Biological Sciences, The University of Auckland, Auckland, New Zealand
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Raffaelli B, Fitzek M, Overeem LH, Storch E, Terhart M, Reuter U. Clinical evaluation of super-responders vs. non-responders to CGRP(-receptor) monoclonal antibodies: a real-world experience. J Headache Pain 2023; 24:16. [PMID: 36843007 PMCID: PMC9969617 DOI: 10.1186/s10194-023-01552-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Accepted: 02/14/2023] [Indexed: 02/28/2023] Open
Abstract
BACKGROUND Clinical trials and real-world studies revealed a spectrum of response to CGRP(-receptor) monoclonal antibodies (mAbs) in migraine prophylaxis, ranging from no effect at all to total migraine freedom. In this study, we aimed to compare clinical characteristics between super-responders (SR) and non-responders (NR) to CGRP(-receptor) mAbs. METHODS We performed a retrospective cohort study at the Headache Center, Charité - Universitätsmedizin Berlin. The definition of super-response was a ≥ 75% reduction in monthly headache days (MHD) in the third month after treatment initiation compared to the month prior to treatment begin (baseline). Non-response was defined as ≤ 25% reduction in MHD after three months of treatment with a CGRP-receptor mAb and subsequent three months of treatment with CGRP mAb, or vice versa. We collected demographic data, migraine disease characteristics, migraine symptoms during the attacks in both study groups (SR/NR) as well as the general medical history. SR and NR were compared using Chi-square test for categorical variables, and t-test for continuous variables. RESULTS Between November 2018 and June 2022, n = 260 patients with migraine received preventive treatment with CGRP(-receptor) mAbs and provided complete headache documentation for the baseline phase and the third treatment month. Among those, we identified n = 29 SR (11%) and n = 26 NR (10%). SR reported more often especially vomiting (SR n = 12/25, 48% vs. NR n = 4/22, 18%; p = 0.031) and typical migraine characteristics such as unilateral localization, pulsating character, photophobia and nausea. A subjective good response to triptans was significantly higher in SR (n = 26/29, 90%) than in NR (n = 15/25, 60%, p = 0.010). NR suffered more frequently from chronic migraine (NR n = 24/26, 92% vs. SR n = 15/29, 52%; p = 0.001), medication overuse headache (NR n = 14/24, 58% versus SR n = 8/29, 28%; p = 0.024), and concomitant depression (NR n = 17/26, 65% vs. SR n = 8/29, 28%; p = 0.005). CONCLUSION Several clinical parameters differ between SR and NR to prophylactic CGRP(-R) mAbs. A thorough clinical evaluation prior to treatment initiation might help to achieve a more personalized management in patients with migraine.
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Affiliation(s)
- Bianca Raffaelli
- grid.6363.00000 0001 2218 4662Department of Neurology, Charité – Universitätsmedizin Berlin, Charitéplatz 1, Berlin, 10117 Germany ,grid.484013.a0000 0004 6879 971XClinician Scientist Program, Berlin Institute of Health at Charité (BIH), Berlin, Germany
| | - Mira Fitzek
- grid.6363.00000 0001 2218 4662Department of Neurology, Charité – Universitätsmedizin Berlin, Charitéplatz 1, Berlin, 10117 Germany
| | - Lucas H. Overeem
- grid.6363.00000 0001 2218 4662Department of Neurology, Charité – Universitätsmedizin Berlin, Charitéplatz 1, Berlin, 10117 Germany
| | - Elisabeth Storch
- grid.6363.00000 0001 2218 4662Department of Neurology, Charité – Universitätsmedizin Berlin, Charitéplatz 1, Berlin, 10117 Germany
| | - Maria Terhart
- grid.6363.00000 0001 2218 4662Department of Neurology, Charité – Universitätsmedizin Berlin, Charitéplatz 1, Berlin, 10117 Germany
| | - Uwe Reuter
- Department of Neurology, Charité - Universitätsmedizin Berlin, Charitéplatz 1, Berlin, 10117, Germany. .,Universitätsmedizin Greifswald, Greifswald, Germany.
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Schiano di Cola F, Ceccardi G, Bolchini M, Caratozzolo S, Liberini P, Padovani A, Rao R. Photophobia and migraine outcome during treatment with galcanezumab. Front Neurol 2023; 13:1088036. [PMID: 36742057 PMCID: PMC9889984 DOI: 10.3389/fneur.2022.1088036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 12/20/2022] [Indexed: 01/19/2023] Open
Abstract
Background Calcitonin gene-related peptide (CGRP) plays a pivotal role in migraine physiology, not only regarding migraine pain but also associated symptoms such as photophobia. The aim of the present study was to assess monoclonal antibodies targeting CGRP efficacy not only in terms of headache and migraine frequency and disability but also in reducing ictal photophobia. Material and methods This is a retrospective observational study, conducted at the Headache Center-ASST Spedali Civili Brescia. All patients in monthly treatment with galcanezumab with at least a 6-month follow-up in September 2022 with reported severe photophobia during migraine attacks were included. Data regarding headache frequency, analgesics consumption, and migraine disability were collected quarterly. Moreover, patients were asked the following information regarding photophobia: (1) whether they noticed an improvement in photophobia during migraine attacks since galcanezumab introduction; (2) the degree of photophobia improvement (low, moderate, and high); and (3) timing photophobia improvement. Results Forty-seven patients were enrolled in the present study as they met the inclusion criteria. Seventeen patients had a diagnosis of high-frequency episodic migraine and 30 of chronic migraine. From baseline to T3 and T6, a significant improvement in terms of headache days (19.2 ± 7.6 vs. 8.6 ± 6.8 vs. 7.7 ± 5.7; p < 0.0001), migraine days (10.4 ± 6.7 vs. 2.9 ± 4.3 vs. 3.6 ± 2.8; p < 0.0001), analgesics consumption (25.1 ± 28.2 vs. 7.6 ± 7.5 vs. 7.6 ± 8.1; p < 0.0001), MIDAS score (82.1 ± 48.4 vs. 21.6 ± 17.6 vs. 18.1 ± 20.5; p < 0.0001), and HIT-6 score (66.2 ± 6.2 vs. 57.2 ± 8.6 vs. 56.6 ± 7.6; p < 0.0001) was found. Thirty-two patients (68.1%) reported a significant improvement in ictal photophobia, with over half of the patients reporting it within the first month of treatment. Photophobia improvement was more frequent in patients with episodic migraine (p = 0.02) and triptans responders (p = 0.03). Conclusions The present study confirms previous reports regarding galcanezumab efficacy beyond migraine frequency. In particular, over 60% of patients, in our cohort, documented a significant improvement also in reducing ictal photophobia. This improvement was, in most patients, moderate to high, and within the first 6 months of treatment, regardless of the clinical response on migraine frequency.
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Begasse de Dhaem O, Wattiez AS, de Boer I, Pavitt S, Powers SW, Pradhan A, Gelfand AA, Nahman-Averbuch H. Bridging the gap between preclinical scientists, clinical researchers, and clinicians: From animal research to clinical practice. Headache 2023; 63:25-39. [PMID: 36633108 DOI: 10.1111/head.14441] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 07/02/2022] [Accepted: 08/26/2022] [Indexed: 01/13/2023]
Abstract
BACKGROUND Collaborations amongst researchers and clinicians with complementary areas of expertise enhance knowledge for everyone and can lead to new discoveries. To facilitate these interactions, shared language and a general understanding of how colleagues in different subfields of headache and headache research approach their work are needed. METHODS This narrative review focuses on research methods applied in animal studies, human studies including clinical trials, and provides an overview of clinical practice. RESULTS For animal studies, we describe concepts needed to evaluate the quality and relevance of preclinical studies. For human research, fundamental concepts of neuroimaging, quantitative sensory testing, genetic and epidemiological research methods, and clinical research methodology that are commonly used in headache research are summarized. In addition, we provide an understanding of what guides headache clinicians, and summarize the practical approach to migraine management in adults and children. CONCLUSIONS It is hoped that this review facilitates further dialogue between clinicians and researchers that will help guide future research efforts and implementation of research findings into clinical practice.
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Affiliation(s)
| | - Anne-Sophie Wattiez
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, Iowa, USA.,Center for the Prevention and Treatment of Visual Loss, Veterans Administration Health Center, Iowa City, Iowa, USA
| | - Irene de Boer
- Department of Neurology, Leiden University Medical Center, Leiden, Netherlands
| | - Sara Pavitt
- Child & Adolescent Headache Program, University of California, San Francisco, California, USA
| | - Scott W Powers
- Division of Behavioral Medicine and Clinical Psychology, Cincinnati Children's Hospital, Cincinnati, Ohio, USA.,Center for Understanding Pediatric Pain, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.,Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Amynah Pradhan
- Department of Psychiatry, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Amy A Gelfand
- Child & Adolescent Headache Program, University of California, San Francisco, California, USA
| | - Hadas Nahman-Averbuch
- Department of Anesthesiology, Washington University Pain Center, Washington University School of Medicine, St. Louis, Missouri, USA
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11
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Yuasa GH, Costa NLVK, Lopes RV, Baggio DF, Rae GA, Chichorro JG. Role of endothelin in the pathophysiology of migraine: A new view on an old player. Neuropeptides 2022; 96:102286. [PMID: 36108557 DOI: 10.1016/j.npep.2022.102286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Revised: 08/30/2022] [Accepted: 09/01/2022] [Indexed: 11/28/2022]
Abstract
There is cumulating evidence that endothelin-1 (ET-1) may play a role in migraine, however controversial findings still impede a conclusion to be drawn. Herein we tested the hypothesis that endothelin ETB receptors are major contributors to migraine-like responses. ET-1, IRL-1620 (selective ETB receptor agonist) or CGRP were injected into the trigeminal ganglion (TG) of female Wistar rats, and the development of periorbital mechanical allodynia was assessed hourly with von Frey hairs. Twenty-four hours later, rats were exposed to an aversive light for 1 h, after which the reactivation of periorbital mechanical allodynia (indicating photic sensitivity) was assessed up to 4 h. Moreover, the effect of systemic Bosentan (ETA/ETB receptors antagonist) or the selective antagonists of ETA (BQ-123) and ETB (BQ-788) receptors injected into the TG were evaluated against CGRP-induced responses. ET-1 and IRL-1620 injection into the TG induced periorbital mechanical allodynia and photic sensitivity. Bosentan attenuated periorbital mechanical allodynia but failed to affect photic sensitivity induced by CGRP. Selective blockade of ETB receptors in the TG fully prevented the development of periorbital mechanical allodynia and photic sensitivity induced by CGRP, but ETA receptor blockade caused only a slight reduction of periorbital mechanical allodynia without affecting photic sensitivity. ETB receptor-operated mechanisms in the TG may contribute to migraine-like responses in female rats.
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Affiliation(s)
- Gianna Hissae Yuasa
- Department of Pharmacology, Biological Sciences Sector, Federal University of Parana, Curitiba, Parana, Brazil
| | | | - Raphael Vieira Lopes
- Department of Pharmacology, Biological Sciences Sector, Federal University of Parana, Curitiba, Parana, Brazil
| | - Darciane Favero Baggio
- Department of Pharmacology, Biological Sciences Sector, Federal University of Parana, Curitiba, Parana, Brazil
| | - Giles Alexander Rae
- Department of Pharmacology, Center of Biological Sciences, Federal University of Santa Catarina, Florianopolis, Santa Catarina, Brazil
| | - Juliana Geremias Chichorro
- Department of Pharmacology, Biological Sciences Sector, Federal University of Parana, Curitiba, Parana, Brazil.
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12
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Strassman AM, Melo-Carrillo A, Houle TT, Adams A, Brin MF, Burstein R. Atogepant - an orally-administered CGRP antagonist - attenuates activation of meningeal nociceptors by CSD. Cephalalgia 2022; 42:933-943. [PMID: 35332801 DOI: 10.1177/03331024221083544] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND This study investigated the mechanism of action of atogepant, a small-molecule CGRP receptor antagonist recently approved for the preventive treatment of episodic migraine, by assessing its effect on activation of mechanosensitive C- and Aδ-meningeal nociceptors following cortical spreading depression. METHODS Single-unit recordings of trigeminal ganglion neurons (32 Aδ and 20 C-fibers) innervating the dura was used to document effects of orally administered atogepant (5 mg/kg) or vehicle on cortical spreading depression-induced activation in anesthetized male rats. RESULTS Bayesian analysis of time effects found that atogepant did not completely prevent the activation of nociceptors at the tested dose, but it significantly reduced response amplitude and probability of response in both the C- and the Aδ-fibers at different time intervals following cortical spreading depression induction. For C-fibers, the reduction in responses was significant in the early phase (first hour), but not delayed phase of activation, whereas in Aδ-fibers, significant reduction in activation was apparent in the delayed phase (second and third hours) but not early phase of activation. CONCLUSIONS These findings identify differences between the actions of atogepant, a small molecule CGRP antagonist (partially inhibiting both Aδ and C-fibers) and those found previously for fremanezumab, a CGRP-targeted antibody (inhibiting Aδ fibers only) and onabotulinumtoxinA (inhibiting C-fibers only)- suggesting that these agents differ in their mechanisms for the preventive treatment of migraine.
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Affiliation(s)
- Andrew M Strassman
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center.,Harvard Medical School, Boston, Massachusetts, USA
| | - Agustin Melo-Carrillo
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center.,Harvard Medical School, Boston, Massachusetts, USA
| | - Timothy T Houle
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, USA
| | - Aubrey Adams
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, USA
| | - Mitchell F Brin
- Allergan, an AbbVie Company, Irvine, CA, USA.,Dept of Neurology, University of California, Irvine, USA
| | - Rami Burstein
- Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center.,Harvard Medical School, Boston, Massachusetts, USA
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13
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Wang M, Mason BN, Sowers LP, Kuburas A, Rea BJ, Russo AF. Investigating Migraine-Like Behavior using Light Aversion in Mice. J Vis Exp 2021. [PMID: 34459825 DOI: 10.3791/62839] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Migraine is a complex neurological disorder characterized by headache and sensory abnormalities, such as hypersensitivity to light, observed as photophobia. Whilst it is impossible to confirm that a mouse is experiencing migraine, light aversion can be used as a behavioral surrogate for the migraine symptom of photophobia. To test for light aversion, we utilize the light/dark assay to measure the time mice freely choose to spend in either a light or dark environment. The assay has been refined by introducing two critical modifications: pre-exposures to the chamber prior to running the test procedure and adjustable chamber lighting, permitting the use of a range of light intensities from 55 lux to 27,000 lux. Because the choice to spend more time in the dark is also indicative of anxiety, we also utilize a light-independent anxiety test, the open field assay, to distinguish anxiety from light-aversive behavior. Here, we describe a modified test paradigm for the light/dark and open field assays. The application of these assays is described for intraperitoneal injection of calcitonin gene-related peptide (CGRP) in two mouse strains and for optogenetic brain stimulation studies.
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Affiliation(s)
- Mengya Wang
- Department of Neuroscience and Pharmacology, University of Iowa
| | - Bianca N Mason
- School of Behavioral and Brain Sciences, University of Texas at Dallas
| | - Levi P Sowers
- Center for the Prevention and Treatment of Visual Loss, Veterans Administration Health Center, Iowa City, IA; Department of Molecular Physiology and Biophysics, University of Iowa
| | - Adisa Kuburas
- Department of Molecular Physiology and Biophysics, University of Iowa
| | - Brandon J Rea
- Center for the Prevention and Treatment of Visual Loss, Veterans Administration Health Center, Iowa City, IA; Department of Molecular Physiology and Biophysics, University of Iowa
| | - Andrew F Russo
- Center for the Prevention and Treatment of Visual Loss, Veterans Administration Health Center, Iowa City, IA; Department of Molecular Physiology and Biophysics, University of Iowa; Department of Neurology, University of Iowa;
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14
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Li C, White TG, Shah KA, Chaung W, Powell K, Wang P, Woo HH, Narayan RK. Percutaneous Trigeminal Nerve Stimulation Induces Cerebral Vasodilation in a Dose-Dependent Manner. Neurosurgery 2021; 88:E529-E536. [PMID: 33677599 DOI: 10.1093/neuros/nyab053] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Accepted: 12/26/2020] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND The trigeminal nerve directly innervates key vascular structures both centrally and peripherally. Centrally, it is known to innervate the brainstem and cavernous sinus, whereas peripherally the trigemino-cerebrovascular network innervates the majority of the cerebral vasculature. Upon stimulation, it permits direct modulation of cerebral blood flow (CBF), making the trigeminal nerve a promising target for the management of cerebral vasospasm. However, trigeminally mediated cerebral vasodilation has not been applied to the treatment of vasospasm. OBJECTIVE To determine the effect of percutaneous electrical stimulation of the infraorbital branch of the trigeminal nerve (pTNS) on the cerebral vasculature. METHODS In order to determine the stimulus-response function of pTNS on cerebral vasodilation, CBF, arterial blood pressure, cerebrovascular resistance, intracranial pressure, cerebral perfusion pressure, cerebrospinal fluid calcitonin gene-related peptide (CGRP) concentrations, and the diameter of cerebral vessels were measured in healthy and subarachnoid hemorrhage (SAH) rats. RESULTS The present study demonstrates, for the first time, that pTNS increases brain CGRP concentrations in a dose-dependent manner, thereby producing controllable cerebral vasodilation. This vasodilatory response appears to be independent of the pressor response induced by pTNS, as it is maintained even after transection of the spinal cord at the C5-C6 level and shown to be confined to the infraorbital nerve by administration of lidocaine or destroying it. Furthermore, such pTNS-induced vasodilatory response of cerebral vessels is retained after SAH-induced vasospasm. CONCLUSION Our study demonstrates that pTNS is a promising vasodilator and increases CBF, cerebral perfusion, and CGRP concentration both in normal and vasoconstrictive conditions.
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Affiliation(s)
- Chunyan Li
- Translational Brain Research Laboratory, The Feinstein Institutes for Medical Research, Manhasset, New York, USA.,Department of Neurosurgery, Zucker School of Medicine at Hofstra/Northwell, Hempstead, New York, USA
| | - Timothy G White
- Department of Neurosurgery, Zucker School of Medicine at Hofstra/Northwell, Hempstead, New York, USA
| | - Kevin A Shah
- Department of Neurosurgery, Zucker School of Medicine at Hofstra/Northwell, Hempstead, New York, USA
| | - Wayne Chaung
- Center for Immunology and Inflammation, The Feinstein Institutes for Medical Research, Manhasset, New York, USA
| | - Keren Powell
- Translational Brain Research Laboratory, The Feinstein Institutes for Medical Research, Manhasset, New York, USA
| | - Ping Wang
- Center for Immunology and Inflammation, The Feinstein Institutes for Medical Research, Manhasset, New York, USA
| | - Henry H Woo
- Department of Neurosurgery, Zucker School of Medicine at Hofstra/Northwell, Hempstead, New York, USA
| | - Raj K Narayan
- Translational Brain Research Laboratory, The Feinstein Institutes for Medical Research, Manhasset, New York, USA.,Department of Neurosurgery, Zucker School of Medicine at Hofstra/Northwell, Hempstead, New York, USA
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15
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CGRP induces migraine-like symptoms in mice during both the active and inactive phases. J Headache Pain 2021; 22:62. [PMID: 34193048 PMCID: PMC8243868 DOI: 10.1186/s10194-021-01277-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 05/31/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Circadian patterns of migraine attacks have been reported by patients but remain understudied. In animal models, circadian phases are generally not taken into consideration. In particular, rodents are nocturnal animals, yet they are most often tested during their inactive phase during the day. This study aims to test the validity of CGRP-induced behavioral changes in mice by comparing responses during the active and inactive phases. METHODS Male and female mice of the outbred CD1 strain were administered vehicle (PBS) or CGRP (0.1 mg/kg, i.p.) to induce migraine-like symptoms. Animals were tested for activity (homecage movement and voluntary wheel running), light aversive behavior, and spontaneous pain at different times of the day and night. RESULTS Peripheral administration of CGRP decreased the activity of mice during the first hour after administration, induced light aversive behavior, and spontaneous pain during that same period of time. Both phenotypes were observed no matter what time of the day or night they were assessed. CONCLUSIONS A decrease in wheel activity is an additional clinically relevant phenotype observed in this model, which is reminiscent of the reduction in normal physical activity observed in migraine patients. The ability of peripheral CGRP to induce migraine-like symptoms in mice is independent of the phase of the circadian cycle. Therefore, preclinical assessment of migraine-like phenotypes can likely be done during the more convenient inactive phase of mice.
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16
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Kuburas A, Mason BN, Hing B, Wattiez AS, Reis AS, Sowers LP, Moldovan Loomis C, Garcia-Martinez LF, Russo AF. PACAP Induces Light Aversion in Mice by an Inheritable Mechanism Independent of CGRP. J Neurosci 2021; 41:4697-4715. [PMID: 33846231 PMCID: PMC8260237 DOI: 10.1523/jneurosci.2200-20.2021] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 02/26/2021] [Accepted: 03/27/2021] [Indexed: 01/18/2023] Open
Abstract
The neuropeptides CGRP (calcitonin gene-related peptide) and PACAP (pituitary adenylate cyclase-activating polypeptide) have emerged as mediators of migraine, yet the potential overlap of their mechanisms remains unknown. Infusion of PACAP, like CGRP, can cause migraine in people, and both peptides share similar vasodilatory and nociceptive functions. In this study, we have used light aversion in mice as a surrogate for migraine-like photophobia to compare CGRP and PACAP and ask whether CGRP or PACAP actions were dependent on each other. Similar to CGRP, PACAP induced light aversion in outbred CD-1 mice. The light aversion was accompanied by increased resting in the dark, but not anxiety in a light-independent open field assay. Unexpectedly, about one-third of the CD-1 mice did not respond to PACAP, which was not seen with CGRP. The responder and nonresponder phenotypes were stable, inheritable, and not sex linked, although there was a trend for greater responses among male mice. RNA-sequencing analysis of trigeminal ganglia yielded hierarchical clustering of responder and nonresponder mice and revealed a number of candidate genes, including greater expression of the Trpc5 and Kcnk12 ion channels and glycoprotein hormones and receptors in a subset of male responder mice. Importantly, an anti-PACAP monoclonal antibody could block PACAP-induced light aversion but not CGRP-induced light aversion. Conversely, an anti-CGRP antibody could not block PACAP-induced light aversion. Thus, we propose that CGRP and PACAP act by independent convergent pathways that cause a migraine-like symptom in mice.SIGNIFICANCE STATEMENT The relationship between the neuropeptides CGRP (calcitonin gene-related peptide) and PACAP (pituitary adenylate cyclase-activating polypeptide) in migraine is relevant given that both peptides can induce migraine in people, yet to date only drugs that target CGRP are available. Using an outbred strain of mice, we were able to show that most, but not all, mice respond to PACAP in a preclinical photophobia assay. Our finding that CGRP and PACAP monoclonal antibodies do not cross-inhibit the other peptide indicates that CGRP and PACAP actions are independent and suggests that PACAP-targeted drugs may be effective in patients who do not respond to CGRP-based therapeutics.
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Affiliation(s)
- Adisa Kuburas
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, Iowa 52242
| | - Bianca N Mason
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, Iowa 52242
- Molecular and Cellular Biology Program, University of Iowa, Iowa City, Iowa 52242
| | - Benjamin Hing
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, Iowa 52242
| | - Anne-Sophie Wattiez
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, Iowa 52242
| | - Alyssa S Reis
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, Iowa 52242
| | - Levi P Sowers
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, Iowa 52242
- Center for the Prevention and Treatment of Visual Loss, Veterans Affairs Health Care System, Iowa City, Iowa 52246
| | | | | | - Andrew F Russo
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, Iowa 52242
- Department of Neurology, University of Iowa, Iowa City, Iowa 52242
- Center for the Prevention and Treatment of Visual Loss, Veterans Affairs Health Care System, Iowa City, Iowa 52246
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