2
|
Lopes SC, da Silva AVL, Arruda BR, Morais TC, Rios JB, Trevisan MTS, Rao VS, Santos FA. Peripheral antinociceptive action of mangiferin in mouse models of experimental pain: role of endogenous opioids, K(ATP)-channels and adenosine. Pharmacol Biochem Behav 2013; 110:19-26. [PMID: 23747933 DOI: 10.1016/j.pbb.2013.05.016] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Revised: 05/23/2013] [Accepted: 05/28/2013] [Indexed: 11/19/2022]
Abstract
This study aimed to assess the possible systemic antinociceptive activity of mangiferin and to clarify the underlying mechanism, using the acute models of chemical (acetic acid, formalin, and capsaicin) and thermal (hot-plate and tail-flick) nociception in mice. Mangiferin at oral doses of 10 to 100 mg/kg evidenced significant antinociception against chemogenic pain in the test models of acetic acid-induced visceral pain and in formalin- and capsaicin-induced neuro-inflammatory pain, in a naloxone-sensitive manner, suggesting the participation of endogenous opiates in its mechanism. In capsaicin test, the antinociceptive effect of mangiferin (30 mg/kg) was not modified by respective competitive and non-competitive transient receptor potential vanilloid 1 (TRPV1) antagonists, capsazepine and ruthenium red, or by pretreatment with L-NAME, a non-selective nitric oxide synthase inhibitor, or by ODQ, an inhibitor of soluble guanylyl cyclase. However, mangiferin effect was significantly reversed by glibenclamide, a blocker of K(ATP) channels and in animals pretreated with 8-phenyltheophylline, an adenosine receptor antagonist. Mangiferin failed to modify the thermal nociception in hot-plate and tail-flick test models, suggesting that its analgesic effect is only peripheral but not central. The orally administered mangiferin (10-100 mg/kg) was well tolerated and did not impair the ambulation or the motor coordination of mice in respective open-field and rota-rod tests, indicating that the observed antinociception was unrelated to sedation or motor abnormality. The findings of this study suggest that mangiferin has a peripheral antinociceptive action through mechanisms that involve endogenous opioids, K(ATP)-channels and adenosine receptors.
Collapse
Affiliation(s)
- Synara C Lopes
- Department of Physiology and Pharmacology, Faculty of Medicine, Federal University of Ceará, 60430-270 Fortaleza, Ceará, Brazil; National Institute of Science and Technology, Institute of Biomedicine of Brazilian Semi-arid, Faculty of Medicine, Federal University of Ceará, 60430-270 Fortaleza, Ceará, Brazil
| | | | | | | | | | | | | | | |
Collapse
|
3
|
Fleckenstein J, Sittl R, Averbeck B, Lang PM, Irnich D, Carr RW. Activation of axonal Kv7 channels in human peripheral nerve by flupirtine but not placebo - therapeutic potential for peripheral neuropathies: results of a randomised controlled trial. J Transl Med 2013; 11:34. [PMID: 23394517 PMCID: PMC3648471 DOI: 10.1186/1479-5876-11-34] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2012] [Accepted: 11/07/2012] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Flupirtine is an analgesic with muscle-relaxing properties that activates Kv7 potassium channels. Kv7 channels are expressed along myelinated and unmyelinated peripheral axons where their activation is expected to reduce axonal excitability and potentially contribute to flupirtine's clinical profile. TRIAL DESIGN To investigate the electrical excitability of peripheral myelinated axons following orally administered flupirtine, in-vitro experiments on isolated peripheral nerve segments were combined with a randomised, double-blind, placebo-controlled, phase I clinical trial (RCT). METHODS Threshold tracking was used to assess the electrical excitability of myelinated axons in isolated segments of human sural nerve in vitro and motoneurones to abductor pollicis brevis (APB) in situ in healthy subjects. In addition, the effect of flupirtine on ectopic action potential generation in myelinated axons was examined using ischemia of the lower arm. RESULTS Flupirtine (3-30 μM) shortened the relative refractory period and increased post-conditioned superexcitability in human myelinated axons in vitro. Similarly, in healthy subjects the relative refractory period of motoneurones to APB was reduced 2 hours after oral flupirtine but not following placebo. Whether this effect was due to a direct action of flupirtine on peripheral axons or temperature could not be resolved. Flupirtine (200 mg p.o.) also reduced ectopic axonal activity induced by 10 minutes of lower arm ischemia. In particular, high frequency (ca. 200 Hz) components of EMG were reduced in the post-ischemic period. Finally, visual analogue scale ratings of sensations perceived during the post-ischemic period were reduced following flupirtine (200 mg p.o.). CONCLUSIONS Clinical doses of flupirtine reduce the excitability of peripheral myelinated axons. TRIAL REGISTRATION ClinicalTrials registration is NCT01450865.
Collapse
|
4
|
Wang CF, Gerner P, Schmidt B, Xu ZZ, Nau C, Wang SY, Ji RR, Wang GK. Use of bulleyaconitine A as an adjuvant for prolonged cutaneous analgesia in the rat. Anesth Analg 2008; 107:1397-405. [PMID: 18806059 DOI: 10.1213/ane.0b013e318182401b] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND Bulleyaconitine A (BLA) is an analgesic and antiinflammatory drug isolated from Aconitum plants. BLA has several potential targets, including voltage-gated Na+ channels. We tested whether BLA elicited long-lasting cutaneous analgesia, when co-injected with lidocaine and epinephrine, as a model for prolonged infiltration anesthesia. METHODS The local anesthetic properties of BLA were assessed by the patch-clamp technique in HEK293t cells expressing Nav1.7 and Nav1.8 neuronal Na+ channels, both crucial for nociception. Drug solutions (0.6 mL) were injected subcutaneously via rat shaved dorsal skin. Inhibition of the cutaneous trunci muscle reflex was evaluated by pinpricks. Skin cross-sections were stained with hematoxylin and eosin or with antibodies against PGP9.5. RESULTS BLA at 10 microM interacted minimally with resting or inactivated Nav1.7 and Nav1.8 Na+ channels when infrequently stimulated to +50 mV for 3 ms. However, when stimulated at 2 Hz for 1000 pulses, their peak Na+ currents were >90% reduced by BLA. This use-dependent inhibition was not significantly reversed after 15-min washing. Complete nociceptive blockade after injection of lidocaine (0.5%)/epinephrine (1:200,000) lasted for approximately 1 h in rats; full recovery occurred after approximately 6 h. Co-injection of 0.125 mM BLA with lidocaine/epinephrine increased the duration of complete nociceptive blockade to 24 h. Full recovery occurred after approximately 6 days. Skin histology including peripheral nerve fibers appeared unaffected by BLA. CONCLUSIONS BLA inhibits Nav1.7 and Nav1.8 Na+ currents in a use-dependent manner. Co-injection of BLA at <or=0.125 mM with lidocaine and epinephrine elicits complete cutaneous analgesia that lasts for up to 24 h without adverse effects.
Collapse
Affiliation(s)
- Chi-Fei Wang
- Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women's Hospital, Harvard Medical School, 75 Francis St., Boston, MA 02115, USA
| | | | | | | | | | | | | | | |
Collapse
|
5
|
Kort ME, Drizin I, Gregg RJ, Scanio MJC, Shi L, Gross MF, Atkinson RN, Johnson MS, Pacofsky GJ, Thomas JB, Carroll WA, Krambis MJ, Liu D, Shieh CC, Zhang X, Hernandez G, Mikusa JP, Zhong C, Joshi S, Honore P, Roeloffs R, Marsh KC, Murray BP, Liu J, Werness S, Faltynek CR, Krafte DS, Jarvis MF, Chapman ML, Marron BE. Discovery and biological evaluation of 5-aryl-2-furfuramides, potent and selective blockers of the Nav1.8 sodium channel with efficacy in models of neuropathic and inflammatory pain. J Med Chem 2008; 51:407-16. [PMID: 18176998 DOI: 10.1021/jm070637u] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Nav1.8 (also known as PN3) is a tetrodotoxin-resistant (TTx-r) voltage-gated sodium channel (VGSC) that is highly expressed on small diameter sensory neurons and has been implicated in the pathophysiology of inflammatory and neuropathic pain. Recent studies using an Nav1.8 antisense oligonucleotide in an animal model of chronic pain indicated that selective blockade of Nav1.8 was analgesic and could provide effective analgesia with a reduction in the adverse events associated with nonselective VGSC blocking therapeutic agents. Herein, we describe the preparation and characterization of a series of 5-substituted 2-furfuramides, which are potent, voltage-dependent blockers (IC50 < 10 nM) of the human Nav1.8 channel. Selected derivatives, such as 7 and 27, also blocked TTx-r sodium currents in rat dorsal root ganglia (DRG) neurons with comparable potency and displayed >100-fold selectivity versus human sodium (Nav1.2, Nav1.5, Nav1.7) and human ether-a-go-go (hERG) channels. Following systemic administration, compounds 7 and 27 dose-dependently reduced neuropathic and inflammatory pain in experimental rodent models.
Collapse
Affiliation(s)
- Michael E Kort
- Global Pharmaceutical Research and Development, Abbott Laboratories, Abbott Park, IL 60064-6100, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
6
|
Jarvis MF, Honore P, Shieh CC, Chapman M, Joshi S, Zhang XF, Kort M, Carroll W, Marron B, Atkinson R, Thomas J, Liu D, Krambis M, Liu Y, McGaraughty S, Chu K, Roeloffs R, Zhong C, Mikusa JP, Hernandez G, Gauvin D, Wade C, Zhu C, Pai M, Scanio M, Shi L, Drizin I, Gregg R, Matulenko M, Hakeem A, Gross M, Johnson M, Marsh K, Wagoner PK, Sullivan JP, Faltynek CR, Krafte DS. A-803467, a potent and selective Nav1.8 sodium channel blocker, attenuates neuropathic and inflammatory pain in the rat. Proc Natl Acad Sci U S A 2007; 104:8520-5. [PMID: 17483457 PMCID: PMC1895982 DOI: 10.1073/pnas.0611364104] [Citation(s) in RCA: 391] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Activation of tetrodotoxin-resistant sodium channels contributes to action potential electrogenesis in neurons. Antisense oligonucleotide studies directed against Na(v)1.8 have shown that this channel contributes to experimental inflammatory and neuropathic pain. We report here the discovery of A-803467, a sodium channel blocker that potently blocks tetrodotoxin-resistant currents (IC(50) = 140 nM) and the generation of spontaneous and electrically evoked action potentials in vitro in rat dorsal root ganglion neurons. In recombinant cell lines, A-803467 potently blocked human Na(v)1.8 (IC(50) = 8 nM) and was >100-fold selective vs. human Na(v)1.2, Na(v)1.3, Na(v)1.5, and Na(v)1.7 (IC(50) values >or=1 microM). A-803467 (20 mg/kg, i.v.) blocked mechanically evoked firing of wide dynamic range neurons in the rat spinal dorsal horn. A-803467 also dose-dependently reduced mechanical allodynia in a variety of rat pain models including: spinal nerve ligation (ED(50) = 47 mg/kg, i.p.), sciatic nerve injury (ED(50) = 85 mg/kg, i.p.), capsaicin-induced secondary mechanical allodynia (ED(50) approximately 100 mg/kg, i.p.), and thermal hyperalgesia after intraplantar complete Freund's adjuvant injection (ED(50) = 41 mg/kg, i.p.). A-803467 was inactive against formalin-induced nociception and acute thermal and postoperative pain. These data demonstrate that acute and selective pharmacological blockade of Na(v)1.8 sodium channels in vivo produces significant antinociception in animal models of neuropathic and inflammatory pain.
Collapse
Affiliation(s)
- Michael F. Jarvis
- *Neuroscience Research, Abbott Laboratories, Abbott Park, IL 60064; and
- To whom correspondence may be addressed at:
Abbott Laboratories, R-4PM, AP9A/3,100 Abbott Park Road, Abbott Park, IL 60064. E-mail:
| | - Prisca Honore
- *Neuroscience Research, Abbott Laboratories, Abbott Park, IL 60064; and
| | - Char-Chang Shieh
- *Neuroscience Research, Abbott Laboratories, Abbott Park, IL 60064; and
| | | | - Shailen Joshi
- *Neuroscience Research, Abbott Laboratories, Abbott Park, IL 60064; and
| | - Xu-Feng Zhang
- *Neuroscience Research, Abbott Laboratories, Abbott Park, IL 60064; and
| | - Michael Kort
- *Neuroscience Research, Abbott Laboratories, Abbott Park, IL 60064; and
| | - William Carroll
- *Neuroscience Research, Abbott Laboratories, Abbott Park, IL 60064; and
| | | | | | | | | | | | - Yi Liu
- Icagen, Inc., Durham, NC 27703
| | - Steve McGaraughty
- *Neuroscience Research, Abbott Laboratories, Abbott Park, IL 60064; and
| | - Katharine Chu
- *Neuroscience Research, Abbott Laboratories, Abbott Park, IL 60064; and
| | | | - Chengmin Zhong
- *Neuroscience Research, Abbott Laboratories, Abbott Park, IL 60064; and
| | - Joseph P. Mikusa
- *Neuroscience Research, Abbott Laboratories, Abbott Park, IL 60064; and
| | | | - Donna Gauvin
- *Neuroscience Research, Abbott Laboratories, Abbott Park, IL 60064; and
| | - Carrie Wade
- *Neuroscience Research, Abbott Laboratories, Abbott Park, IL 60064; and
| | - Chang Zhu
- *Neuroscience Research, Abbott Laboratories, Abbott Park, IL 60064; and
| | - Madhavi Pai
- *Neuroscience Research, Abbott Laboratories, Abbott Park, IL 60064; and
| | - Marc Scanio
- *Neuroscience Research, Abbott Laboratories, Abbott Park, IL 60064; and
| | - Lei Shi
- *Neuroscience Research, Abbott Laboratories, Abbott Park, IL 60064; and
| | - Irene Drizin
- *Neuroscience Research, Abbott Laboratories, Abbott Park, IL 60064; and
| | - Robert Gregg
- *Neuroscience Research, Abbott Laboratories, Abbott Park, IL 60064; and
| | - Mark Matulenko
- *Neuroscience Research, Abbott Laboratories, Abbott Park, IL 60064; and
| | - Ahmed Hakeem
- *Neuroscience Research, Abbott Laboratories, Abbott Park, IL 60064; and
| | | | | | - Kennan Marsh
- *Neuroscience Research, Abbott Laboratories, Abbott Park, IL 60064; and
| | | | - James P. Sullivan
- *Neuroscience Research, Abbott Laboratories, Abbott Park, IL 60064; and
| | | | - Douglas S. Krafte
- Icagen, Inc., Durham, NC 27703
- To whom correspondence may be addressed at:
Icagen, Inc., P.O. Box 14487, Research Triangle Park, NC 27709. E-mail:
| |
Collapse
|
7
|
Dong XW, Goregoaker S, Engler H, Zhou X, Mark L, Crona J, Terry R, Hunter J, Priestley T. Small interfering RNA-mediated selective knockdown of NaV1.8 tetrodotoxin-resistant sodium channel reverses mechanical allodynia in neuropathic rats. Neuroscience 2007; 146:812-21. [PMID: 17367951 DOI: 10.1016/j.neuroscience.2007.01.054] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2006] [Revised: 01/23/2007] [Accepted: 01/26/2007] [Indexed: 01/10/2023]
Abstract
The biophysical properties of a tetrodotoxin resistant (TTXr) sodium channel, Na(V)1.8, and its restricted expression to the peripheral sensory neurons suggest that blocking this channel might have therapeutic potential in various pain states and may offer improved tolerability compared with existing sodium channel blockers. However, the role of Na(V)1.8 in nociception cannot be tested using a traditional pharmacological approach with small molecules because currently available sodium channel blockers do not distinguish between sodium channel subtypes. We sought to determine whether small interfering RNAs (siRNAs) might be capable of achieving the desired selectivity. Using Northern blot analysis and membrane potential measurement, several siRNAs were identified that were capable of a highly-selective attenuation of Na(V)1.8 message as well as functional expression in clonal ND7/23 cells which were stably transfected with the rat Na(V)1.8 gene. Functional knockdown of the channel was confirmed using whole-cell voltage-clamp electrophysiology. One of the siRNA probes showing a robust knockdown of Na(V)1.8 current was evaluated for in vivo efficacy in reversing an established tactile allodynia in the rat chronic constriction nerve-injury (CCI) model. The siRNA, which was delivered to lumbar dorsal root ganglia (DRG) via an indwelling epidural cannula, caused a significant reduction of Na(V)1.8 mRNA expression in lumbar 4 and 5 (L4-L5) DRG neurons and consequently reversed mechanical allodynia in CCI rats. We conclude that silencing of Na(V)1.8 channel using a siRNA approach is capable of producing pain relief in the CCI model and further support a role for Na(V)1.8 in pathological sensory dysfunction.
Collapse
Affiliation(s)
- X-W Dong
- Department of Neurobiology, Schering-Plough Research Institute, K-15-2-2600, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA.
| | | | | | | | | | | | | | | | | |
Collapse
|