1
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Xie YF, Yang J, Ratté S, Prescott SA. Similar excitability through different sodium channels and implications for the analgesic efficacy of selective drugs. eLife 2024; 12:RP90960. [PMID: 38687187 PMCID: PMC11060714 DOI: 10.7554/elife.90960] [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] [Indexed: 05/02/2024] Open
Abstract
Nociceptive sensory neurons convey pain-related signals to the CNS using action potentials. Loss-of-function mutations in the voltage-gated sodium channel NaV1.7 cause insensitivity to pain (presumably by reducing nociceptor excitability) but clinical trials seeking to treat pain by inhibiting NaV1.7 pharmacologically have struggled. This may reflect the variable contribution of NaV1.7 to nociceptor excitability. Contrary to claims that NaV1.7 is necessary for nociceptors to initiate action potentials, we show that nociceptors can achieve similar excitability using different combinations of NaV1.3, NaV1.7, and NaV1.8. Selectively blocking one of those NaV subtypes reduces nociceptor excitability only if the other subtypes are weakly expressed. For example, excitability relies on NaV1.8 in acutely dissociated nociceptors but responsibility shifts to NaV1.7 and NaV1.3 by the fourth day in culture. A similar shift in NaV dependence occurs in vivo after inflammation, impacting ability of the NaV1.7-selective inhibitor PF-05089771 to reduce pain in behavioral tests. Flexible use of different NaV subtypes exemplifies degeneracy - achieving similar function using different components - and compromises reliable modulation of nociceptor excitability by subtype-selective inhibitors. Identifying the dominant NaV subtype to predict drug efficacy is not trivial. Degeneracy at the cellular level must be considered when choosing drug targets at the molecular level.
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Affiliation(s)
- Yu-Feng Xie
- Neurosciences and Mental Health, The Hospital for Sick ChildrenTorontoCanada
| | - Jane Yang
- Neurosciences and Mental Health, The Hospital for Sick ChildrenTorontoCanada
- Institute of Biomedical Engineering, University of TorontoTorontoCanada
| | - Stéphanie Ratté
- Neurosciences and Mental Health, The Hospital for Sick ChildrenTorontoCanada
| | - Steven A Prescott
- Neurosciences and Mental Health, The Hospital for Sick ChildrenTorontoCanada
- Institute of Biomedical Engineering, University of TorontoTorontoCanada
- Department of Physiology, University of TorontoTorontoCanada
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2
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Sun Z, Meng P, Su C, Ji S, Gao Y, Wang H, Tian J, Li C. PCC-0105002, a novel small molecule inhibitor of PSD95-nNOS protein-protein interactions, attenuates neuropathic pain and corrects motor disorder associated with neuropathic pain model. Toxicol Appl Pharmacol 2021; 429:115698. [PMID: 34428447 DOI: 10.1016/j.taap.2021.115698] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 08/16/2021] [Accepted: 08/18/2021] [Indexed: 01/11/2023]
Abstract
In view of postsynaptic density 95kDA (PSD95) tethers neuronal NO synthase (nNOS) to N-methyl-d-aspartate receptor (NMDAR), the PSD95-nNOS complex represents a therapeutic target of neuropathic pain. This study therefore sought to explore the ability of PCC-0105002, a novel PSD95-nNOS small molecule inhibitor, to alter pain sensitivity in rodent neuropathic pain models. Firstly, the IC50 of PCC-0105002 for PSD95 and NOS1 binding activity was determined using an Alpha Screen assay kit. Then, we examined the effects of PCC-0105002 in the mouse formalin test and in the rat spinal nerve ligation (SNL) model, and explored the ability of PCC-0105002 to mediate analgesia and to effect motor coordination in a rota-rod test. Moreover, the mechanisms whereby PCC-0105002 mediates analgesia was explored via western blotting, Golgi staining, and co-immunoprecipitation experiments in dorsal horn. The outcomes indicated that PCC-0105002 exhibited dose-dependent attenuation of phase II pain-associated behaviors in the formalin test. The result indicated that PCC-0105002 disrupted the PSD95-nNOS interaction with IC50 of 1.408 μM. In the SNL model, PCC-0105002 suppressed mechanical allodynia, thermal hyperalgesia, and abnormal dorsal horn wide dynamic range neuron discharge. PCC-0105002 mediated an analgesic effect comparable to that of MK-801, while it was better able to enhance motor coordination as compared with MK-801. Moreover, PCC-0105002 altered signaling downstream of NMDAR and thus functionally and structurally attenuating synaptic plasticity through respective regulation of the NR2B/GluR1/CaMKIIα and Rac1/RhoA pathways. These findings suggest that the novel PSD95-nNOS inhibitor PCC-0105002 is an effective agent for alleviating neuropathic pain, and that it produces fewer motor coordination-associated side effects than do NMDAR antagonists.
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Affiliation(s)
- Zhihong Sun
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai, China
| | - Ping Meng
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai, China
| | - Chunyu Su
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai, China
| | - Shengmin Ji
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai, China
| | - Yonglin Gao
- School of Life Science, Yantai University, Yantai 264005, China
| | - Hongbo Wang
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai, China
| | - Jingwei Tian
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai, China.
| | - Chunmei Li
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai, China.
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3
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Franco NH, Miranda SB, Kovács N, Nagy A, Thiện BQ, Reis F, Varga O. Assessing Scientific Soundness and Translational Value of Animal Studies on DPP4 Inhibitors for Treating Type 2 Diabetes Mellitus. BIOLOGY 2021; 10:155. [PMID: 33669354 PMCID: PMC7920304 DOI: 10.3390/biology10020155] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 02/10/2021] [Accepted: 02/13/2021] [Indexed: 12/14/2022]
Abstract
Although there is a wide range of animal models of type 2 diabetes mellitus (T2DM) used in research; we have limited evidence on their translation value. This paper provides a) a comparison of preclinical animal and clinical results on the effect of five dipeptidyl peptidase-4 (DPP4) inhibitors by comparing the pharmaceutical caused glucose changes, and b) an evaluation of methodological and reporting standards in T2DM preclinical animal studies. DPP4 inhibitors play an important role in the clinical management of T2DM: if metformin alone is not sufficient enough to control the blood sugar levels, DPP4 inhibitors are often used as second-line therapy; additionally, DPP-4 inhibitors are also used in triple therapies with metformin and sodium-glucose co-transporter-2 (SGLT-2) inhibitors or with metformin and insulin. In our analysis of 124 preclinical studies and 47 clinical trials, (1) we found no evidence of species differences in glucose change response to DPP4 inhibitors, which may suggest that, for this drug class, studies in mice and rats may be equally predictive of how well a drug will work in humans; and (2) there is good reporting of group size, sex, age, euthanasia method and self-reported compliance with animal welfare regulations in animal studies but poor reporting of justification of group size, along with a strong bias towards the use of male animals and young animals. Instead of the common non-transparent model selection, we call for a reflective and evidenced-based assessment of predictive validity of the animal models currently available.
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Affiliation(s)
- Nuno Henrique Franco
- Laboratory Animal Science Group, IBMC—Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; (N.H.F.); (S.B.M.)
- Instituto de Investigação e Inovação da Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal
| | - Sonia Batista Miranda
- Laboratory Animal Science Group, IBMC—Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; (N.H.F.); (S.B.M.)
- Instituto de Investigação e Inovação da Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal
| | - Nóra Kovács
- Department of Public Health and Epidemiology, Faculty of Medicine, University of Debrecen, Kassai út 26, 4028 Debrecen, Hungary;
| | - Attila Nagy
- Faculty of Public Health, University of Debrecen, Kassai út 26, 4028 Debrecen, Hungary;
| | - Bùi Quốc Thiện
- Faculty of Medicine, University of Debrecen, Egyetem Square 1, 4032 Debrecen, Hungary;
| | - Flávio Reis
- Institute of Pharmacology and Experimental Therapeutics, and Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, 3000-548 Coimbra, Portugal;
- Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, 3004-504 Coimbra, Portugal
- Clinical Academic Center of Coimbra (CACC), 3004-504 Coimbra, Portugal
| | - Orsolya Varga
- Department of Public Health and Epidemiology, Faculty of Medicine, University of Debrecen, Kassai út 26, 4028 Debrecen, Hungary;
- Office for Research Groups Attached to Universities and Other Institutions, Hungarian Academy of Sciences, 1051 Budapest, Hungary
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4
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Li C, Su C, Wang Z, Han R, Wang Y, Wang H, Tian J, Gao Y. WITHDRAWN: PCC-0105002, a novel small molecule inhibitor of PSD95-nNOS protein-protein interactions, attenuates neuropathic pain and corrects motor coordination-associated side effects in neuropathic pain model. Toxicol Appl Pharmacol 2020:115208. [PMID: 32828906 DOI: 10.1016/j.taap.2020.115208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 08/06/2020] [Accepted: 08/18/2020] [Indexed: 11/28/2022]
Abstract
This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.
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Affiliation(s)
- Chunmei Li
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai, China
| | - Chunyu Su
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai, China
| | - Zhezhe Wang
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai, China
| | - Rui Han
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai, China
| | - Yu Wang
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai, China
| | - Hongbo Wang
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai, China
| | - Jingwei Tian
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in Universities of Shandong, Yantai University, Yantai, China.
| | - Yonglin Gao
- School of Life Science, Yantai University, Yantai 264005, China.
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5
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St. Germain DC, O’Mara AM, Robinson JL, Torres AD, Minasian LM. Chemotherapy‐induced peripheral neuropathy: Identifying the research gaps and associated changes to clinical trial design. Cancer 2020; 126:4602-4613. [DOI: 10.1002/cncr.33108] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Revised: 06/11/2020] [Accepted: 06/17/2020] [Indexed: 12/25/2022]
Affiliation(s)
| | - Ann M. O’Mara
- Division of Cancer Prevention National Cancer Institute Bethesda Maryland
| | - Jennifer L. Robinson
- Department of Behavioral and Community Health University of Maryland College Park Maryland
| | | | - Lori M. Minasian
- Division of Cancer Prevention National Cancer Institute Bethesda Maryland
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6
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Siebenga P, van Amerongen G, Hay JL, McDonnell A, Gorman D, Butt R, Groeneveld GJ. Lack of Detection of the Analgesic Properties of PF-05089771, a Selective Na v 1.7 Inhibitor, Using a Battery of Pain Models in Healthy Subjects. Clin Transl Sci 2019; 13:318-324. [PMID: 31642607 PMCID: PMC7070789 DOI: 10.1111/cts.12712] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Accepted: 09/06/2019] [Indexed: 12/12/2022] Open
Abstract
Sodium channel blockers are used for the treatment of pain, but this is limited by the lack of selectivity for different sodium channel subtypes, which can result in central nervous system and cardiovascular side effects. As such, there is special interest in the Nav 1.7 subtype, which is expressed predominantly in nociceptive and sympathetic neurons. The aim was to demonstrate analgesic properties of a potent selective Nav 1.7 sodium channel blocker, PF-05089771, alone and concomitantly with pregabalin in healthy subjects using a battery of human evoked pain models. This was a double-blind, double-dummy, randomized, placebo-controlled, five-period cross-over study with PF-05089771 alone and PF-05089771 concomitantly with pregabalin as treatment arms with pregabalin, ibuprofen, and placebo as control arms (NCT02349607). A battery of human evoked pain models was used to investigate analgesic properties of PF-05089771. Twenty-five subjects were enrolled in the study of which 23 subjects completed all five periods. PF-05089771 alone did not differ from placebo on the primary pain end points. The same holds when comparing PF-05089771 concomitantly with pregabalin and pregabalin alone. Pregabalin showed significant effects relative to placebo on thermal pain on the normal skin and UVB skin (least squares means with 90% confidence interval: 0.63 (0.32-0.93) and 0.53 (0.11-0.96)), pressure stimulation (1.10 (1.04-1.18)), and cold pressor (1.22 (1.14-1.32)). Ibuprofen demonstrated significant effects on thermal pain UVB skin (1.26 (0.82-1.70)) and pressure stimulation assessment (1.08 (1.01-1.15)), consistent with historical results. This study did not demonstrate analgesic properties of PF-05089771 alone or concomitantly with pregabalin in a battery of pain models.
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Affiliation(s)
| | | | - Justin L Hay
- Centre for Human Drug Research, Leiden, The Netherlands
| | | | - Donal Gorman
- Neuroscience and Pain Research Unit, Pfizer WRD, Cambridge, UK
| | - Richard Butt
- Neuroscience and Pain Research Unit, Pfizer WRD, Cambridge, UK
| | - Geert Jan Groeneveld
- Centre for Human Drug Research, Leiden, The Netherlands.,Leiden University Medical Centre, Leiden, The Netherlands
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7
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Yu H, Zhao T, Liu S, Wu Q, Johnson O, Wu Z, Zhuang Z, Shi Y, Peng L, He R, Yang Y, Sun J, Wang X, Xu H, Zeng Z, Zou P, Lei X, Luo W, Li Y. MRGPRX4 is a bile acid receptor for human cholestatic itch. eLife 2019; 8:48431. [PMID: 31500698 PMCID: PMC6773440 DOI: 10.7554/elife.48431] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Accepted: 09/02/2019] [Indexed: 02/06/2023] Open
Abstract
Patients with liver diseases often suffer from chronic itch, yet the pruritogen(s) and receptor(s) remain largely elusive. Here, we identify bile acids as natural ligands for MRGPRX4. MRGPRX4 is expressed in human dorsal root ganglion (hDRG) neurons and co-expresses with itch receptor HRH1. Bile acids elicited Ca2+ responses in cultured hDRG neurons, and bile acids or a MRGPRX4 specific agonist induced itch in human subjects. However, a specific agonist for another bile acid receptor TGR5 failed to induce itch in human subjects and we find that human TGR5 is not expressed in hDRG neurons. Finally, we show positive correlation between cholestatic itch and plasma bile acids level in itchy patients and the elevated bile acids is sufficient to activate MRGPRX4. Taken together, our data strongly suggest that MRGPRX4 is a novel bile acid receptor that likely underlies cholestatic itch in human, providing a promising new drug target for anti-itch therapies.
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Affiliation(s)
- Huasheng Yu
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, China.,PKU-IDG/McGovern Institute for Brain Research, Beijing, China.,Peking-Tsinghua Center for Life Sciences, Beijing, China
| | - Tianjun Zhao
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, China.,PKU-IDG/McGovern Institute for Brain Research, Beijing, China.,Peking-Tsinghua Center for Life Sciences, Beijing, China
| | - Simin Liu
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, China
| | - Qinxue Wu
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, United States
| | - Omar Johnson
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, United States
| | - Zhaofa Wu
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, China.,PKU-IDG/McGovern Institute for Brain Research, Beijing, China
| | - Zihao Zhuang
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, China
| | - Yaocheng Shi
- Department of Chemical Biology, College of Chemistry and Molecular Engineering, Peking University, Beijing, China
| | - Luxin Peng
- Department of Chemical Biology, College of Chemistry and Molecular Engineering, Peking University, Beijing, China
| | - Renxi He
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, China.,PKU-IDG/McGovern Institute for Brain Research, Beijing, China
| | - Yong Yang
- Department of Dermatology, Beijing Key Laboratory of Molecular Diagnosis on Dermatoses, Peking University First Hospital, Peking University, Beijing, China
| | - Jianjun Sun
- Department of Neurosurgery, Peking University Third Hospital, Peking University, Beijing, China
| | - Xiaoqun Wang
- State Key Laboratory of Brain and Cognitive Science, CAS Center for Excellence in Brain Science and Intelligence Technology (Shanghai), Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Haifeng Xu
- Department of Liver Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China
| | - Zheng Zeng
- Department of Infectious Diseases, Peking University First Hospital, Beijing, China
| | - Peng Zou
- Department of Chemical Biology, College of Chemistry and Molecular Engineering, Peking University, Beijing, China
| | - Xiaoguang Lei
- Peking-Tsinghua Center for Life Sciences, Beijing, China.,Department of Chemical Biology, College of Chemistry and Molecular Engineering, Peking University, Beijing, China
| | - Wenqin Luo
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, United States
| | - Yulong Li
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, China.,PKU-IDG/McGovern Institute for Brain Research, Beijing, China.,Peking-Tsinghua Center for Life Sciences, Beijing, China.,Chinese Institute for Brain Research, Beijing, China
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8
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Yezierski RP, Hansson P. Inflammatory and Neuropathic Pain From Bench to Bedside: What Went Wrong? THE JOURNAL OF PAIN 2018; 19:571-588. [DOI: 10.1016/j.jpain.2017.12.261] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Revised: 11/29/2017] [Accepted: 12/13/2017] [Indexed: 12/31/2022]
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9
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Sałat K, Gryzło B, Kulig K. Experimental Drugs for Neuropathic Pain. Curr Neuropharmacol 2018; 16:1193-1209. [PMID: 29745335 PMCID: PMC6187752 DOI: 10.2174/1570159x16666180510151241] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 02/02/2018] [Accepted: 05/07/2018] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Neuropathic pain (NP) is an important public health problem and despite recent progress in the understanding, diagnosis, pathophysiological mechanisms and the treatment of NP, many patients remain refractory to pharmacotherapy. OBJECTIVE Currently used drugs have limited efficacy and dose-limiting adverse effects, and thus there is a substantial need for further development of novel medications for its treatment. Alternatively, drugs approved for use in diseases other than NP can be applied as experimental for NP conditions. This paper covers advances in the field of NP treatment. RESULTS The prime focus of this paper is on drugs with well-established pharmacological activity whose current therapeutic applications are distinct from NP. These drugs could be a potential novel treatment of NP. Data from preclinical studies and clinical trials on these experimental drugs are presented. The development of advanced methods of genomics enabled to propose new targets for drugs which could be effective in the NP treatment. CONCLUSION Experimental drugs for NP can be a treatment option which should be tailor-made for each individual on the basis of pain features, previous therapies, associated clinical conditions, recurrence of pain, adverse effects, contraindications and patients' preferences. At present, there are only some agents which may have potential as novel treatments. Increasing knowledge about mechanisms underlying NP, mechanisms of drug action, as well as available data from preclinical and clinical studies make botulinum toxin A, minocycline, ambroxol, statins and PPAR agonists (ATx086001) promising potential future treatment options.
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Affiliation(s)
- Kinga Sałat
- Address correspondence to this author at the Faculty of Pharmacy,
Jagiellonian University, 9 Medyczna St., 30-688 Kraków, Poland; Tel: + 48 12 6205 555; Fax: + 48 12 6205 554; E-mail:
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10
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Taneja A, Della Pasqua O, Danhof M. Challenges in translational drug research in neuropathic and inflammatory pain: the prerequisites for a new paradigm. Eur J Clin Pharmacol 2017; 73:1219-1236. [PMID: 28894907 PMCID: PMC5599481 DOI: 10.1007/s00228-017-2301-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Accepted: 07/03/2017] [Indexed: 12/21/2022]
Abstract
AIM Despite an improved understanding of the molecular mechanisms of nociception, existing analgesic drugs remain limited in terms of efficacy in chronic conditions, such as neuropathic pain. Here, we explore the underlying pathophysiological mechanisms of neuropathic and inflammatory pain and discuss the prerequisites and opportunities to reduce attrition and high-failure rate in the development of analgesic drugs. METHODS A literature search was performed on preclinical and clinical publications aimed at the evaluation of analgesic compounds using MESH terms in PubMed. Publications were selected, which focused on (1) disease mechanisms leading to chronic/neuropathic pain and (2) druggable targets which are currently under evaluation in drug development. Attention was also given to the role of biomarkers and pharmacokinetic-pharmacodynamic modelling. RESULTS Multiple mechanisms act concurrently to produce pain, which is a non-specific manifestation of underlying nociceptive pathways. Whereas these manifestations can be divided into neuropathic and inflammatory pain, it is now clear that inflammatory mechanisms are a common trigger for both types of pain. This has implications for drug development, as the assessment of drug effects in experimental models of neuropathic and chronic pain is driven by overt behavioural measures. By contrast, the use of mechanistic biomarkers in inflammatory pain has provided the pharmacological basis for dose selection and evaluation of non-steroidal anti-inflammatory drugs (NSAIDs). CONCLUSION A different paradigm is required for the identification of relevant targets and candidate molecules whereby pain is coupled to the cause of sensorial signal processing dysfunction rather than clinical symptoms. Biomarkers which enable the characterisation of drug binding and target activity are needed for a more robust dose rationale in early clinical development. Such an approach may be facilitated by quantitative clinical pharmacology and evolving technologies in brain imaging, allowing accurate assessment of target engagement, and prediction of treatment effects before embarking on large clinical trials.
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Affiliation(s)
- A Taneja
- Division of Pharmacology, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands
| | - O Della Pasqua
- Division of Pharmacology, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands.,Clinical Pharmacology Modelling & Simulation, GlaxoSmithKline, Uxbridge, UK.,Clinical Pharmacology & Therapeutics Group, University College London, London, UK
| | - M Danhof
- Division of Pharmacology, Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands.
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11
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Taylor JC, Dewberry LS, Totsch SK, Yessick LR, DeBerry JJ, Watts SA, Sorge RE. A novel zebrafish-based model of nociception. Physiol Behav 2017; 174:83-88. [DOI: 10.1016/j.physbeh.2017.03.009] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 03/07/2017] [Accepted: 03/09/2017] [Indexed: 12/21/2022]
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12
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Valtcheva MV, Copits BA, Davidson S, Sheahan TD, Pullen MY, McCall JG, Dikranian K, Gereau RW. Surgical extraction of human dorsal root ganglia from organ donors and preparation of primary sensory neuron cultures. Nat Protoc 2016; 11:1877-88. [PMID: 27606776 PMCID: PMC5082842 DOI: 10.1038/nprot.2016.111] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Primary cultures of rodent sensory neurons are widely used to investigate the cellular and molecular mechanisms involved in pain, itch, nerve injury and regeneration. However, translation of these preclinical findings may be greatly improved by direct validation in human tissues. We have developed an approach to extract and culture human sensory neurons in collaboration with a local organ procurement organization (OPO). Here we describe the surgical procedure for extraction of human dorsal root ganglia (hDRG) and the necessary modifications to existing culture techniques to prepare viable adult human sensory neurons for functional studies. Dissociated sensory neurons can be maintained in culture for >10 d, and they are amenable to electrophysiological recording, calcium imaging and viral gene transfer. The entire process of extraction and culturing can be completed in <7 h, and it can be performed by trained graduate students. This approach can be applied at any institution with access to organ donors consenting to tissue donation for research, and is an invaluable resource for improving translational research.
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Affiliation(s)
- Manouela V Valtcheva
- Washington University Pain Center and Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri, USA.,Medical Scientist Training Program, Washington University in St. Louis, St. Louis, Missouri, USA.,Neurosciences Program, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Bryan A Copits
- Washington University Pain Center and Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Steve Davidson
- Washington University Pain Center and Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri, USA.,Pain Research Center, Department of Anesthesiology, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Tayler D Sheahan
- Washington University Pain Center and Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri, USA.,Neurosciences Program, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Melanie Y Pullen
- Washington University Pain Center and Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri, USA.,Developmental, Regenerative, and Stem Cell Biology Program, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Jordan G McCall
- Washington University Pain Center and Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Krikor Dikranian
- Department of Neuroscience, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Robert W Gereau
- Washington University Pain Center and Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri, USA
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Förster M, Helfert S, Dierschke R, Großkopf M, Hüllemann P, Keller T, Baron R, Binder A. Evaluation of the antihyperalgesic effect of tapentadol in two human evoked pain models – the TapCapMentho pilot trial. Expert Opin Pharmacother 2016; 17:1717-25. [DOI: 10.1080/14656566.2016.1201071] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- M. Förster
- Division of Neurological Pain Research and Therapy, Department of Neurology, Christian-Albrechts-Universität Kiel, Kiel, Germany
| | - S. Helfert
- Division of Neurological Pain Research and Therapy, Department of Neurology, Christian-Albrechts-Universität Kiel, Kiel, Germany
| | - R. Dierschke
- Division of Neurological Pain Research and Therapy, Department of Neurology, Christian-Albrechts-Universität Kiel, Kiel, Germany
| | - M. Großkopf
- Division of Neurological Pain Research and Therapy, Department of Neurology, Christian-Albrechts-Universität Kiel, Kiel, Germany
| | - P. Hüllemann
- Division of Neurological Pain Research and Therapy, Department of Neurology, Christian-Albrechts-Universität Kiel, Kiel, Germany
| | | | - R. Baron
- Division of Neurological Pain Research and Therapy, Department of Neurology, Christian-Albrechts-Universität Kiel, Kiel, Germany
| | - A. Binder
- Division of Neurological Pain Research and Therapy, Department of Neurology, Christian-Albrechts-Universität Kiel, Kiel, Germany
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14
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15
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Whiteside GT, Pomonis JD, Kennedy JD. Preclinical Pharmacological Approaches in Drug Discovery for Chronic Pain. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2016; 75:303-23. [PMID: 26920017 DOI: 10.1016/bs.apha.2015.12.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
In recent years, animal behavioral models, particularly those used in pain research, have been increasingly scrutinized and criticized for their role in the poor translation of novel pharmacotherapies for chronic pain. This chapter addresses the use of animal models of pain used in drug discovery research. It highlights how, when, and why animal models of pain are used as one of the many experimental tools used to gain better understanding of target mechanisms and rank-order compounds in the iterative process of establishing structure-activity relationship. Together, these models help create an "analgesic signature" for a compound and inform the indications most likely to yield success in clinical trials. In addition, the authors discuss some often underappreciated aspects of currently used (traditional) animal models of pain, including simply applying basic pharmacological principles to study design and data interpretation as well as consideration of efficacy alongside side effect measures as part of the overall conclusion of efficacy. This is provided to add perspective regarding current efforts to develop new models and endpoints both in rodents and in larger animal species as well as assess cognitive and/or affective aspects of pain. Finally, the authors suggest ways in which efficacy evaluation in animal models of pain, whether traditional or new, might better align with clinical standards of analysis, citing examples where applying effect size and number needed to treat estimations to animal model data suggest that the efficacy bar often may be set too low preclinically to allow successful translation to the clinical setting.
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Affiliation(s)
| | - James D Pomonis
- American Preclinical Services, LLC, Minneapolis, Minnesota, USA
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16
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Marson L, Giamberardino MA, Costantini R, Czakanski P, Wesselmann U. Animal Models for the Study of Female Sexual Dysfunction. Sex Med Rev 2015; 1:108-122. [PMID: 27784584 DOI: 10.1002/smrj.14] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
INTRODUCTION Significant progress has been made in elucidating the physiological and pharmacological mechanisms of female sexual function through preclinical animal research. The continued development of animal models is vital for the understanding and treatment of the many diverse disorders that occur in women. AIM To provide an updated review of the experimental models evaluating female sexual function that may be useful for clinical translation. METHODS Review of English written, peer-reviewed literature, primarily from 2000 to 2012, that described studies on female sexual behavior related to motivation, arousal, physiological monitoring of genital function and urogenital pain. MAIN OUTCOMES MEASURES Analysis of supporting evidence for the suitability of the animal model to provide measurable indices related to desire, arousal, reward, orgasm, and pelvic pain. RESULTS The development of female animal models has provided important insights in the peripheral and central processes regulating sexual function. Behavioral models of sexual desire, motivation, and reward are well developed. Central arousal and orgasmic responses are less well understood, compared with the physiological changes associated with genital arousal. Models of nociception are useful for replicating symptoms and identifying the neurobiological pathways involved. While in some cases translation to women correlates with the findings in animals, the requirement of circulating hormones for sexual receptivity in rodents and the multifactorial nature of women's sexual function requires better designed studies and careful analysis. The current models have studied sexual dysfunction or pelvic pain in isolation; combining these aspects would help to elucidate interactions of the pathophysiology of pain and sexual dysfunction. CONCLUSIONS Basic research in animals has been vital for understanding the anatomy, neurobiology, and physiological mechanisms underlying sexual function and urogenital pain. These models are important for understanding the etiology of female sexual function and for future development of pharmacological treatments for sexual dysfunctions with or without pain. Marson L, Giamberardino MA, Costantini R, Czakanski P, and Wesselmann U. Animal models for the study of female sexual dysfunction. Sex Med Rev 2013;1:108-122.
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Affiliation(s)
- Lesley Marson
- University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
| | | | | | - Peter Czakanski
- University of Alabama at Birmingham-Departments of Anesthesiology and Obstetrics & Gynecology, Birmingham, AL, USA
| | - Ursula Wesselmann
- University of Alabama at Birmingham-Departments of Anesthesiology and Neurology, Birmingham, AL, USA
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17
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Gunduz O, Topuz R, Karadag C, Ulugol A. Analysis of the anti-allodynic effects of combination of a synthetic cannabinoid and a selective noradrenaline re-uptake inhibitor in nerve injury-induced neuropathic mice. Eur J Pain 2015. [DOI: 10.1002/ejp.752] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- O. Gunduz
- Department of Medical Pharmacology; Faculty of Medicine; Trakya University; 22030-Edirne Turkey
| | - R.D. Topuz
- Department of Medical Pharmacology; Faculty of Medicine; Trakya University; 22030-Edirne Turkey
| | - C.H. Karadag
- Department of Medical Pharmacology; Faculty of Medicine; Trakya University; 22030-Edirne Turkey
| | - A. Ulugol
- Department of Medical Pharmacology; Faculty of Medicine; Trakya University; 22030-Edirne Turkey
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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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Alexandrov V, Brunner D, Hanania T, Leahy E. Reprint of: Highthroughtput analysis of behavior for drug discovery. Eur J Pharmacol 2015; 753:127-34. [DOI: 10.1016/j.ejphar.2015.02.037] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Revised: 11/14/2014] [Accepted: 11/26/2014] [Indexed: 10/23/2022]
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20
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High-throughput analysis of behavior for drug discovery. Eur J Pharmacol 2015; 750:82-9. [PMID: 25592319 PMCID: PMC4552324 DOI: 10.1016/j.ejphar.2014.11.047] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Revised: 11/14/2014] [Accepted: 11/26/2014] [Indexed: 12/21/2022]
Abstract
Drug testing with traditional behavioral assays constitutes a major bottleneck in the development of novel therapies. PsychoGenics developed three comprehensive highthroughtput systems, SmartCube®, NeuroCube® and PhenoCube® systems, to increase the efficiency of the drug screening and phenotyping in rodents. These three systems capture different domains of behavior, namely, cognitive, motor, circadian, social, anxiety-like, gait and others, using custom-built computer vision software and machine learning algorithms for analysis. This review exemplifies the use of the three systems and explains how they can advance drug screening with their applications to phenotyping of disease models, drug screening, selection of lead candidates, behavior-driven lead optimization, and drug repurposing.
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21
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Gereau RW, Sluka KA, Maixner W, Savage SR, Price TJ, Murinson BB, Sullivan MD, Fillingim RB. A pain research agenda for the 21st century. THE JOURNAL OF PAIN 2014; 15:1203-14. [PMID: 25419990 DOI: 10.1016/j.jpain.2014.09.004] [Citation(s) in RCA: 113] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Revised: 08/12/2014] [Accepted: 09/16/2014] [Indexed: 12/21/2022]
Abstract
UNLABELLED Chronic pain represents an immense clinical problem. With tens of millions of people in the United States alone suffering from the burden of debilitating chronic pain, there is a moral obligation to reduce this burden by improving the understanding of pain and treatment mechanisms, developing new therapies, optimizing and testing existing therapies, and improving access to evidence-based pain care. Here, we present a goal-oriented research agenda describing the American Pain Society's vision for pain research aimed at tackling the most pressing issues in the field. PERSPECTIVE This article presents the American Pain Society's view of some of the most important research questions that need to be addressed to advance pain science and to improve care of patients with chronic pain.
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Affiliation(s)
- Robert W Gereau
- The American Pain Society, Glenview, Illinois; Washington University Pain Center and Department of Anesthesiology, Washington University School of Medicine, St. Louis, Missouri
| | - Kathleen A Sluka
- The American Pain Society, Glenview, Illinois; Department of Physical Therapy and Rehabilitation Science, Pain Research Program, University of Iowa, Iowa City, Iowa
| | - William Maixner
- The American Pain Society, Glenview, Illinois; Center for Pain Research and Innovation, University of North Carolina, Chapel Hill, North Carolina
| | - Seddon R Savage
- The American Pain Society, Glenview, Illinois; Department of Anesthesiology and Center on Addiction Recovery and Education, Dartmouth Medical School, Hanover, New Hampshire
| | - Theodore J Price
- The American Pain Society, Glenview, Illinois; School of Brain and Behavioral Sciences, University of Texas at Dallas, Dallas, Texas
| | - Beth B Murinson
- The American Pain Society, Glenview, Illinois; Department of Neurology, The Johns Hopkins School of Medicine, Baltimore, Maryland
| | - Mark D Sullivan
- The American Pain Society, Glenview, Illinois; Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, Washington
| | - Roger B Fillingim
- The American Pain Society, Glenview, Illinois; Pain Research and Intervention Center of Excellence, University of Florida, Gainesville, Florida.
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Edelmayer RM, Brederson JD, Jarvis MF, Bitner RS. Biochemical and pharmacological assessment of MAP-kinase signaling along pain pathways in experimental rodent models: a potential tool for the discovery of novel antinociceptive therapeutics. Biochem Pharmacol 2014; 87:390-8. [DOI: 10.1016/j.bcp.2013.11.019] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Revised: 11/19/2013] [Accepted: 11/20/2013] [Indexed: 12/28/2022]
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23
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Brabb T, Carbone L, Snyder J, Phillips N. Institutional animal care and use committee considerations for animal models of peripheral neuropathy. ILAR J 2014; 54:329-37. [PMID: 24615447 PMCID: PMC4383225 DOI: 10.1093/ilar/ilt045] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Peripheral neuropathy and neuropathic pain are debilitating, life-altering conditions that affect a significant proportion of the human population. Animal models, used to study basic disease mechanisms and treatment modalities, are diverse and provide many challenges for institutional animal care and use committee (IACUC) review and postapproval monitoring. Items to consider include regulatory and ethical imperatives in animal models that may be designed to study pain, the basic mechanism of neurodegeneration, and different disease processes for which neuropathic pain is a side effect. Neuropathic pain can be difficult to detect or quantify in many models, and pain management is often unsuccessful in both humans and animals, inspiring the need for more research. Design of humane endpoints requires clear communication of potential adverse outcomes and solutions. Communication with the IACUC, researchers, and veterinary staff is also key for successful postapproval monitoring of these challenging models.
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Affiliation(s)
- Thea Brabb
- Address correspondence and reprint requests to Dr. Thea Brabb, Box 357190, University of Washington, Seattle, WA 98195 or email
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24
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Taneja A, Troconiz IF, Danhof M, Della Pasqua O. Semi-mechanistic modelling of the analgesic effect of gabapentin in the formalin-induced rat model of experimental pain. Pharm Res 2013; 31:593-606. [PMID: 24096967 DOI: 10.1007/s11095-013-1183-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2013] [Accepted: 08/09/2013] [Indexed: 12/27/2022]
Abstract
PURPOSE The formalin-induced rat model of nociception involves moderate continuous pain. Formalin-induced pain results in a typical repetitive flinching behaviour, which displays a biphasic pattern characterised by peaks of pain. Here we described the time course of pain response and the analgesic effect of gabapentin using a semi-mechanistic modelling approach. METHODS Male Sprague-Dawley rats received gabapentin (10-100 mg/kg) or placebo 1 h prior to the formalin injection, as per standard protocol. A reduction in the frequency of the second peak of flinching was used as a behavioural measure of gabapentin-mediated anti-nociception. The flinching response was modelled using a mono-exponential function to characterise the first peak and an indirect response model with a time variant synthesis rate for the second. PKPD modelling was performed using a population approach in NONMEM v.7.1.2. RESULTS The time course of the biphasic response was adequately described by the proposed model, which included separate expressions for each phase. Gabapentin was found to reversibly decrease, but not suppress the flinching frequency of the second response peak only. The mean IC50 estimate was 7,510 ng/ml, with relative standard error (RSE%) of 40%. CONCLUSIONS A compartmental, semi-mechanistic model provides the basis for further understanding of the formalin-induced flinching response and consequently to better characterisation of the properties of gabapentin, such as the potency in individual animals. Moreover, despite high exposure levels, model predictions show that gabapentin does not completely suppress behavioural response in the formalin-induced pain model.
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Affiliation(s)
- A Taneja
- Division of Pharmacology, Leiden Academic Centre for Drug Research, POBox 9502, 2300 RA, Leiden, The Netherlands
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Whiteside GT, Pomonis JD, Kennedy JD. An industry perspective on the role and utility of animal models of pain in drug discovery. Neurosci Lett 2013; 557 Pt A:65-72. [PMID: 23994390 DOI: 10.1016/j.neulet.2013.08.033] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Revised: 08/14/2013] [Accepted: 08/17/2013] [Indexed: 12/17/2022]
Abstract
In recent years, animal behavioral models, particularly those used in pain research, have been increasingly scrutinized and criticized for their role in the poor translation of novel pharmacotherapies for chronic pain. This article addresses the use of animal models of pain from the perspective of industrial drug discovery research. It highlights how, when, and why animal models of pain are used as one of the many experimental tools used to gain better understanding of target mechanisms and rank-order compounds in the iterative process of establishing structure-activity relationships (SAR). Together, these models help create an 'analgesic signature' for a compound and inform the indications most likely to yield success in clinical trials. In addition, the authors discuss some often under-appreciated aspects of currently used (traditional) animal models of pain, including how industry balances efficacy with side effect measures as part of the overall conclusion of efficacy. This is provided to add perspective regarding current efforts to develop new models and endpoints both in rodents and larger animal species as well as assess cognitive and/or affective aspects of pain. Finally, the authors suggest ways in which efficacy evaluation in animal models of pain, whether traditional or new, might better align with clinical standards of analysis, citing examples where applying effect size and NNT estimations to animal model data suggest that the efficacy bar often may be set too low preclinically to allow successful translation to the clinical setting.
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Affiliation(s)
- Garth T Whiteside
- Discovery Research, Purdue Pharma L.P., 6 Cedar Brook Drive, Cranbury, NJ 08512, United States
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Höke A, Simpson DM, Freeman R. Challenges in developing novel therapies for peripheral neuropathies: a summary of The Foundation for Peripheral Neuropathy Scientific Symposium 2012. J Peripher Nerv Syst 2013; 18:1-6. [PMID: 23521637 DOI: 10.1111/jns5.12000] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | | | - Roy Freeman
- Department of Neurology, Harvard Medical School, Beth Israel Deaconess Medical Center; Boston MA USA
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Taneja A, Nyberg J, Danhof M, Della Pasqua O. Optimised protocol design for the screening of analgesic compounds in neuropathic pain. J Pharmacokinet Pharmacodyn 2012. [PMID: 23197246 DOI: 10.1007/s10928-012-9277-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
We have previously shown how screening experiments for neuropathic pain can be optimised taking into account parameter and model uncertainty. Here we demonstrate how optimised protocols can be used to screen and rank candidate molecules. The concept is illustrated by pregabalin as a new chemical entity and gabapentin as a reference compound. ED-optimality was applied to a logistic regression model describing the relationship between drug exposure and response to evoked pain in the complete Freund's adjuvant (CFA) model in rats. Design variables for optimisation of the experimental protocol included dose levels and sampling times. Prior information from the reference compound was used in conjunction with relative in vitro potency as priors. Results from simulated scenarios were then combined with fitting of experimental data to estimate precision and bias of model parameters for the empirical and optimised designs. The pharmacokinetics of pregabalin was described by a two-compartment model. The expected value of EC(50) of pregabalin was 637.5 ng ml(-1). Model-based analysis of the data yielded median (range) of EC(50) values of 1,125 (898-2412) ng ml(-1) for the empirical protocol and 755 (189-756) ng ml(-1) for the optimised design. In contrast to current practice, optimal design entails different sampling schedule across dose levels. ED-optimised designs should become standard practice in the screening of candidate molecules. It ensures lower bias when estimating the drug potency, facilitating accurate ranking and selection of compounds for further development.
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Affiliation(s)
- A Taneja
- Division of Pharmacology, LACDR, Leiden University, Leiden, The Netherlands
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Taneja A, Nyberg J, de Lange ECM, Danhof M, Della Pasqua O. Application of ED-optimality to screening experiments for analgesic compounds in an experimental model of neuropathic pain. J Pharmacokinet Pharmacodyn 2012. [PMID: 23197247 DOI: 10.1007/s10928-012-9278-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
In spite of the evidence regarding high variability in the response to evoked pain, little attention has been paid to its impact on the screening of drugs for inflammatory and neuropathic pain. In this study, we explore the feasibility of introducing optimality concepts to experimental protocols, enabling estimation of parameter and model uncertainty. Pharmacokinetic (PK) and pharmacodynamic data from different experiments in rats were pooled and modelled using nonlinear mixed effects modelling. Pain data on gabapentin and placebo-treated animals were generated in the complete Freund's adjuvant model of neuropathic pain. A logistic regression model was applied to optimise sampling times and dose levels to be used in an experimental protocol. Drug potency (EC(50)) and interindividual variability (IIV) were considered the parameters of interest. Different experimental designs were tested and validated by SSE (stochastic simulation and estimation) taking into account relevant exposure ranges. The pharmacokinetics of gabapentin was described by a two-compartment PK model with first order absorption (CL = 0.159 l h(-1), V(2) = 0.118 l, V(3) = 0.253 l, Ka = 0.26 h(-1), Q = 1.22 l h(-1)). Drug potency (EC(50)) for the anti-allodynic effects was estimated to be 1400 ng ml(-1). Protocol optimisation improved bias and precision of the EC50 by 6 and 11.9. %, respectively, whilst IIV estimates showed improvement of 31.89 and 14.91 %, respectively. Our results show that variability in behavioural models of evoked pain response leads to uncertainty in drug potency estimates, with potential impact on the ranking of compounds during screening. As illustrated for gabapentin, ED-optimality concepts enable analysis of discrete data taking into account experimental constraints.
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Affiliation(s)
- A Taneja
- Division of Pharmacology, LACDR, Leiden University, Leiden, The Netherlands
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Mao J. Current challenges in translational pain research. Trends Pharmacol Sci 2012; 33:568-73. [PMID: 22959652 PMCID: PMC3482290 DOI: 10.1016/j.tips.2012.08.001] [Citation(s) in RCA: 90] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2012] [Revised: 08/08/2012] [Accepted: 08/13/2012] [Indexed: 12/31/2022]
Abstract
The current gap between basic science research and the development of new analgesics presents a serious challenge for the future of pain medicine. This challenge is particularly difficult in the search for better treatment for comorbid chronic pain conditions because: (i) animal 'pain' models do not simulate multidimensional clinical pain conditions; (ii) animal behavioral testing does not assess subjective pain experience; (iii) preclinical data provide little assurance regarding the direction of new analgesic development; and (iv) clinical trials routinely use over-sanitized study populations and fail to capture the multidisciplinary consequences of comorbid chronic pain. Therefore, a paradigm shift in translational pain research is necessary to transform the current strategy from focusing on molecular switches of nociception to studying pain as a system-based integral response that includes psychosocial comorbidities. Several key issues of translational pain research are discussed in this review.
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Affiliation(s)
- Jianren Mao
- MGH Center for Translational Pain Research, Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA.
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