- Email: [email protected]
Role and activation mechanism of the Transient Receptor Potential Ankyrin 1 (TRPA1) ion channel in mouse models of chronic pain
Abstracts
doi:10.1016/j.npep.2017.02.008
S2/3 ROLE AND ACTIVATION MECHANISM OF THE TRANSIENT RECEPTOR POTENTIAL ANKYRIN 1 (TRPA1) ION CHANNEL IN MOUSE MODELS OF CHRONIC PAIN Zsuzsanna Helyesa,b, Balint Scheichc, Adam Horvathc, Balint Botzc, Valeria Tekusc, Andrea Czompad, Robert Ludmerczkid, Erika Pinterb,c, Janka Csepregie, Janos Szolcsanyib,c, Attila Mocsaie, Peter Matyusd; a Department of Pharmacology and Pharmacotherapy, Janos Szentagothai Research Centre, Centre of Neuroscience, MTA-PTE NAP B Chronic Pain Research Group, University of Pécs Medical School, Pécs, Hungary; b PharmInVivo Ltd., Pécs, Hungary; cDepartment of Pharmacology and Pharmacotherapy, Janos Szentagothai Research Centre, Centre of Neuroscience, University of Pécs Medical School, Pécs, Hungary; d Department of Organic Chemistry, Semmelweis University, Budapest, Hungary; eDepartment of Physiology, and MTA-SE “Lendület” Inflammation Physiology Research Group, Semmelweis University, Budapest, Hungary
DP
Studies supported by BHF (PG/12/34/29557), Novo Nordisk and BBSRC. (1) Russell FA et al. (2014). Physiol Rev 94: 1099-142. (2) Aubdool et al. (2014). Nat Commun 5:5732. (3) Bodkin et al. (2014). Pharmacol Res Perspect 2:e00052. (4) Smillie SJ et al. (2014). Hypertension 63: 1056-62.
HNO formed by NO and H2S increases meningeal blood flow through activation of TRPA1 receptor channels and subsequent CGRP release. This signalling cascade activating TRPA1 receptors of trigeminal afferents may be involved in primary headaches.
OF
subsequent restorative blood flow is dependent on TRPA1 activation, mediated by CGRP and nitric-oxide. The TRPA1-CGRP dilator pathway is thus important in the physiological reflex to local cold response. However, the influence of this pathway is less understood systemically. Using the angiotensin II (AngII) model, we showed that TRPA1 deletion does not influence hypertension3. As CGRPKO mice show an exacerbated hypertensive phenotype4, this suggests that TRPA1 cannot respond to cardiovascular stress mediated by AngII in the mouse. Our most recent results showed that daily systemic administration of a CGRP agonist protects against AngII-induced hypertension, reducing blood pressure, vascular aortic and cardiac hypertrophy, fibrosis and oxidative stress in mice. This provides evidence for a potential novel therapeutic strategy, with the concept that CGRP agonists mediate anti-hypertensive and anti-cardiac remodelling effects when treatment starts early onset of hypertension. Whilst the activity of TRPA1 to release CGRP from sensory nerves appears to be site and stimulus specific, CGRP whether released endogenously or administered appears protective.
RO
130
doi:10.1016/j.npep.2017.02.007
TE
S2/2
Few contradictory data are available about the activation and pathophysiological relevance of Transient Receptor Potential Ankyrin 1 (TRPA1) in chronic inflammation and pain. Noxious mediators produced by the semicarbazide-sensitive amine-oxydase (SSAO) during tissue injury, such as formaldehyde and methylglyoxal, are its stimulators, but link between TRPA1 and SSAO products, and analgesic effect of SSAO inhibitors have not been investigated. We studied the role of TRPA1, SSAO, and their interactions in chronic pain models. Traumatic mononeuropathy was induced by sciatic nerve ligation, arthritis by complete Freund's adjuvant or K/BxN arthritogenic serum transfer in TRPA1 gene-deficient (TRPA1-/-) mice and wildtypes (WT). The mechanonociceptive threshold was measured by aesthesiometry, thermonociception by hot plate, cold sensitivity in 0°C water, paw volume by plethysmometry, clinical severity by scoring, grasping on a grid, myeloperoxidase activity by luminescence and vascular leakage by fluorescence imaging. Similar mechanical, but reduced cold hyperalgesia developed in neuropathic TRPA1-deficient mice compared to WTs. Adjuvantinduced mechanical hyperalgesia, swelling, early myeloperoxidase activity, late vascular leakage were significantly reduced in TRPA1-/animals. In K/BxN arthritis hyperalgesia was diminished in the late stage, but inflammatory parameters were unaltered by TRPA1 deletion. The SSAO inhibitor SzV-1287 (20 mg/kg) significantly reduced neuropathic mechanical hyperalgesia involving central sensitization in WT mice, but not in TRPA1-/- ones. SzV-1287 decreased hyperalgesia in both groups in both arthritis models, although inflammation was minimally affected. TRPA1 is involved in chronic neuropathic and arthritic pain. SSAO inhibition exerts potent analgesic effects, which is TRPA1-mediated in neuropathy, but not in arthritis.
H2S-NO-TRPA1-CGRP SIGNALLING CONTROLS MENINGEAL BLOOD FLOW
RR
EC
Maria Duxa, Christine Willb, Birgit Voglerb, Milos R. Filipovicc, Karl Messlingerb; aDepartment of Physiology, University of Szeged, Szeged, Hungary; bInstitute of Physiology and Pathophysiology, University of Erlangen-Nürnberg, Erlangen, Germany; cDepartment of Chemistry and Pharmacy, University of Erlangen-Nürnberg, Erlangen, Germany
UN
CO
Calcitonin gene-related peptide (CGRP) and nitric oxide (NO) released in the dura mater encephali mediate meningeal blood flow elevation possibly linked to the pathopysiology of headaches. Thereby nitroxyl (HNO) generated by the reaction of NO with hydrogen sulfide (H2S) may be a major vasodilatory agent. We investigated the involvement of HNO in meningeal blood flow regulation and CGRP release in models of meningeal nociception. Meningeal blood flow was recorded in an open cranial window preparation by laser Doppler flowmetry. CGRP released from the dura mater was measured in the hemisected rat head preparation and quantified using ELISA. Neuronal NOS- (nNOS) and transient receptor potential ankyrin 1 (TRPA1) immunoreactivity was identified in dura mater whole mounts. NO, H2S and HNO were histochemically detected in the dura mater. Topical administration of the NO donor DEA-NONOate increased meningeal blood flow. This response was reduced by preadministration of oxamic acid, an inhibitor of H2S synthesis. The H2S precursor Na2S also elevated meningeal blood flow. This effect was abolished by blocking the TRPA1 or the CGRP receptor. Na2S caused dose-dependent CGRP release, facilitated by co-administration of DEA-NONOate. TRPA1, nNOS, H2S and HNO were histochemically localised to arterial vessels or perivascular nerve fibre bundles. HNO staining was lost after pretreatment with L-NMMA and oxamic acid.
Support: KTIA_NAP_13-2014-0022 (888819), OTKA-NN 114458. doi:10.1016/j.npep.2017.02.009
doi:10.1016/j.npep.2017.02.008
S2/3 ROLE AND ACTIVATION MECHANISM OF THE TRANSIENT RECEPTOR POTENTIAL ANKYRIN 1 (TRPA1) ION CHANNEL IN MOUSE MODELS OF CHRONIC PAIN Zsuzsanna Helyesa,b, Balint Scheichc, Adam Horvathc, Balint Botzc, Valeria Tekusc, Andrea Czompad, Robert Ludmerczkid, Erika Pinterb,c, Janka Csepregie, Janos Szolcsanyib,c, Attila Mocsaie, Peter Matyusd; a Department of Pharmacology and Pharmacotherapy, Janos Szentagothai Research Centre, Centre of Neuroscience, MTA-PTE NAP B Chronic Pain Research Group, University of Pécs Medical School, Pécs, Hungary; b PharmInVivo Ltd., Pécs, Hungary; cDepartment of Pharmacology and Pharmacotherapy, Janos Szentagothai Research Centre, Centre of Neuroscience, University of Pécs Medical School, Pécs, Hungary; d Department of Organic Chemistry, Semmelweis University, Budapest, Hungary; eDepartment of Physiology, and MTA-SE “Lendület” Inflammation Physiology Research Group, Semmelweis University, Budapest, Hungary
DP
Studies supported by BHF (PG/12/34/29557), Novo Nordisk and BBSRC. (1) Russell FA et al. (2014). Physiol Rev 94: 1099-142. (2) Aubdool et al. (2014). Nat Commun 5:5732. (3) Bodkin et al. (2014). Pharmacol Res Perspect 2:e00052. (4) Smillie SJ et al. (2014). Hypertension 63: 1056-62.
HNO formed by NO and H2S increases meningeal blood flow through activation of TRPA1 receptor channels and subsequent CGRP release. This signalling cascade activating TRPA1 receptors of trigeminal afferents may be involved in primary headaches.
OF
subsequent restorative blood flow is dependent on TRPA1 activation, mediated by CGRP and nitric-oxide. The TRPA1-CGRP dilator pathway is thus important in the physiological reflex to local cold response. However, the influence of this pathway is less understood systemically. Using the angiotensin II (AngII) model, we showed that TRPA1 deletion does not influence hypertension3. As CGRPKO mice show an exacerbated hypertensive phenotype4, this suggests that TRPA1 cannot respond to cardiovascular stress mediated by AngII in the mouse. Our most recent results showed that daily systemic administration of a CGRP agonist protects against AngII-induced hypertension, reducing blood pressure, vascular aortic and cardiac hypertrophy, fibrosis and oxidative stress in mice. This provides evidence for a potential novel therapeutic strategy, with the concept that CGRP agonists mediate anti-hypertensive and anti-cardiac remodelling effects when treatment starts early onset of hypertension. Whilst the activity of TRPA1 to release CGRP from sensory nerves appears to be site and stimulus specific, CGRP whether released endogenously or administered appears protective.
RO
130
doi:10.1016/j.npep.2017.02.007
TE
S2/2
Few contradictory data are available about the activation and pathophysiological relevance of Transient Receptor Potential Ankyrin 1 (TRPA1) in chronic inflammation and pain. Noxious mediators produced by the semicarbazide-sensitive amine-oxydase (SSAO) during tissue injury, such as formaldehyde and methylglyoxal, are its stimulators, but link between TRPA1 and SSAO products, and analgesic effect of SSAO inhibitors have not been investigated. We studied the role of TRPA1, SSAO, and their interactions in chronic pain models. Traumatic mononeuropathy was induced by sciatic nerve ligation, arthritis by complete Freund's adjuvant or K/BxN arthritogenic serum transfer in TRPA1 gene-deficient (TRPA1-/-) mice and wildtypes (WT). The mechanonociceptive threshold was measured by aesthesiometry, thermonociception by hot plate, cold sensitivity in 0°C water, paw volume by plethysmometry, clinical severity by scoring, grasping on a grid, myeloperoxidase activity by luminescence and vascular leakage by fluorescence imaging. Similar mechanical, but reduced cold hyperalgesia developed in neuropathic TRPA1-deficient mice compared to WTs. Adjuvantinduced mechanical hyperalgesia, swelling, early myeloperoxidase activity, late vascular leakage were significantly reduced in TRPA1-/animals. In K/BxN arthritis hyperalgesia was diminished in the late stage, but inflammatory parameters were unaltered by TRPA1 deletion. The SSAO inhibitor SzV-1287 (20 mg/kg) significantly reduced neuropathic mechanical hyperalgesia involving central sensitization in WT mice, but not in TRPA1-/- ones. SzV-1287 decreased hyperalgesia in both groups in both arthritis models, although inflammation was minimally affected. TRPA1 is involved in chronic neuropathic and arthritic pain. SSAO inhibition exerts potent analgesic effects, which is TRPA1-mediated in neuropathy, but not in arthritis.
H2S-NO-TRPA1-CGRP SIGNALLING CONTROLS MENINGEAL BLOOD FLOW
RR
EC
Maria Duxa, Christine Willb, Birgit Voglerb, Milos R. Filipovicc, Karl Messlingerb; aDepartment of Physiology, University of Szeged, Szeged, Hungary; bInstitute of Physiology and Pathophysiology, University of Erlangen-Nürnberg, Erlangen, Germany; cDepartment of Chemistry and Pharmacy, University of Erlangen-Nürnberg, Erlangen, Germany
UN
CO
Calcitonin gene-related peptide (CGRP) and nitric oxide (NO) released in the dura mater encephali mediate meningeal blood flow elevation possibly linked to the pathopysiology of headaches. Thereby nitroxyl (HNO) generated by the reaction of NO with hydrogen sulfide (H2S) may be a major vasodilatory agent. We investigated the involvement of HNO in meningeal blood flow regulation and CGRP release in models of meningeal nociception. Meningeal blood flow was recorded in an open cranial window preparation by laser Doppler flowmetry. CGRP released from the dura mater was measured in the hemisected rat head preparation and quantified using ELISA. Neuronal NOS- (nNOS) and transient receptor potential ankyrin 1 (TRPA1) immunoreactivity was identified in dura mater whole mounts. NO, H2S and HNO were histochemically detected in the dura mater. Topical administration of the NO donor DEA-NONOate increased meningeal blood flow. This response was reduced by preadministration of oxamic acid, an inhibitor of H2S synthesis. The H2S precursor Na2S also elevated meningeal blood flow. This effect was abolished by blocking the TRPA1 or the CGRP receptor. Na2S caused dose-dependent CGRP release, facilitated by co-administration of DEA-NONOate. TRPA1, nNOS, H2S and HNO were histochemically localised to arterial vessels or perivascular nerve fibre bundles. HNO staining was lost after pretreatment with L-NMMA and oxamic acid.
Support: KTIA_NAP_13-2014-0022 (888819), OTKA-NN 114458. doi:10.1016/j.npep.2017.02.009