Dataset Information

Protease activated receptor 2 (PAR2) activation causes migraine-like pain behaviors in mice.

ABSTRACT: BACKGROUND:Pain is the most debilitating symptom of migraine. The cause of migraine pain likely requires activation of meningeal nociceptors. Mast cell degranulation, with subsequent meningeal nociceptor activation, has been implicated in migraine pathophysiology. Degranulating mast cells release serine proteases that can cleave and activate protease activated receptors. The purpose of these studies was to investigate whether protease activated receptor 2 is a potential generator of nociceptive input from the meninges by using selective pharmacological agents and knockout mice. METHODS:Ratiometric Ca++ imaging was performed on primary trigeminal and dural cell cultures after application of 2at-LIGRL-NH2, a specific protease activated receptor 2 agonist. Cutaneous hypersensitivity and facial grimace was measured in wild-type and protease activated receptor 2-/- mice after dural application of 2at-LIGRL-NH2 or compound 48-80, a mast cell degranulator. Behavioral experiments were also conducted in mice after dural application of 2at-LIGRL-NH2 (2AT) in the presence of either C391, a selective protease activated receptor 2 antagonist, or sumatriptan. RESULTS:2at-LIGRL-NH2 evoked Ca2+ signaling in mouse trigeminal neurons, dural fibroblasts and in meningeal afferents. Dural application of 2at-LIGRL-NH2 or 48-80 caused dose-dependent grimace behavior and mechanical allodynia that were attenuated by either local or systemic application of C391 as well as in protease activated receptor 2-/- mice. Nociceptive behavior after dural injection of 2at-LIGRL-NH2 was also attenuated by sumatriptan. CONCLUSIONS:Functional protease activated receptor 2 receptors are expressed on both dural afferents and fibroblasts and activation of dural protease activated receptor 2 produces migraine-like behavioral responses. Protease activated receptor 2 may link resident immune cells to meningeal nociceptor activation, driving migraine-like pain and implicating protease activated receptor 2 as a therapeutic target for migraine in humans.

SUBMITTER: Hassler SN

PROVIDER: S-EPMC6081257 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Protease activated receptor 2 (PAR2) activation causes migraine-like pain behaviors in mice.

Hassler Shayne N SN Ahmad Fatima B FB Burgos-Vega Carolina C CC Boitano Scott S Vagner Josef J Price Theodore J TJ Dussor Gregory G

Cephalalgia : an international journal of headache 20180531 1

<h4>Background</h4>Pain is the most debilitating symptom of migraine. The cause of migraine pain likely requires activation of meningeal nociceptors. Mast cell degranulation, with subsequent meningeal nociceptor activation, has been implicated in migraine pathophysiology. Degranulating mast cells release serine proteases that can cleave and activate protease activated receptors. The purpose of these studies was to investigate whether protease activated receptor 2 is a potential generator of noci ...[more]

PMID: 29848111

Similar Datasets

Project description:Given the limited options and often harmful side effects of current analgesics and the suffering caused by the opioid crisis, new classes of pain therapeutics are needed. Protease-activated receptors (PARs), particularly PAR2, are implicated in a variety of pathologies, including pain. Since the discovery of the role of PAR2 in pain, development of potent and specific antagonists has been slow. In this study, we describe the in vivo characterization of a novel small molecule/peptidomimetic hybrid compound, C781, as a β-arrestin-biased PAR2 antagonist. In vivo behavioral studies were done in mice using von Frey filaments and the Mouse Grimace Scale. Pharmacokinetic studies were done to assess pharmacokinetic/pharmacodynamic relationship in vivo. We used both prevention and reversal paradigms with protease treatment to determine whether C781 could attenuate protease-evoked pain. C781 effectively prevented and reversed mechanical and spontaneous nociceptive behaviors in response to small molecule PAR2 agonists, mast cell activators, and neutrophil elastase. The ED50 of C781 (intraperitoneal dosing) for inhibition of PAR2 agonist (20.9 ng 2-AT)-evoked nociception was 6.3 mg/kg. C781 was not efficacious in the carrageenan inflammation model. Pharmacokinetic studies indicated limited long-term systemic bioavailability for C781 suggesting that optimizing pharmacokinetic properties could improve in vivo efficacy. Our work demonstrates in vivo efficacy of a biased PAR2 antagonist that selectively inhibits β-arrestin/MAPK signaling downstream of PAR2. Given the importance of this signaling pathway in PAR2-evoked nociception, C781 exemplifies a key pharmacophore for PAR2 that can be optimized for clinical development. PERSPECTIVE: Our work provides evidence that PAR2 antagonists that only block certain aspects of signaling by the receptor can be effective for blocking protease-evoked pain in mice. This is important because it creates a rationale for developing safer PAR2-targeting approaches for pain treatment.

Project description:Chronic liver inflammation and fibrosis in nonalcoholic steatohepatitis can lead to cirrhosis and liver failure for which there are currently no approved treatments. Protease-activated receptor-2 (PAR2) is an emerging new target expressed on liver stellate cells and hepatocytes that regulates the response to liver injury and inflammation. Here, we identified a pepducin to block the deleterious actions of PAR2 in promoting liver fibrosis. Non-alcoholic fatty liver disease and early fibrosis were induced by the methionine-choline-deficient diet in mice. Fibrotic liver disease was induced by administering carbon tetrachloride for 8 weeks. Mice were treated with the pepducin PZ-235 either from onset of the experiment or after fibrosis was established. Hepatic fibrosis, collagen content, inflammatory cytokines, steatosis, triglycerides, and NAFLD activity score were assessed as primary outcome parameters depending on the model. The activity of the PAR2 pepducin on cultured stellate cell activation and hepatocyte reactive oxygen species production was evaluated. PZ-235 significantly suppressed liver fibrosis, collagen deposition, inflammatory cytokines, NAFLD activity score, steatosis, triglycerides, aspartate transaminase, alanine transaminase, and stellate cell proliferation by up to 50-100%. The PAR2 inhibitor afforded significant protective effects against hepatocellular necrosis and attenuated PAR2-mediated reactive oxygen species production in hepatocytes. PZ-235 was distributed to liver and other mouse tissues and was found to form a well structured ?-helix that closely resembles the juxtamembrane helical region of the analogous TM6 and third intracellular region of the intact receptor that is critical for coupling to internal G proteins. The ability of PZ-235 to effectively suppress fibrosis, hepatocellular necrosis, reactive oxygen species production, steatosis, and inflammation indicates the potential for PAR2 pepducin inhibitors to be broadly efficacious in the treatment of liver fibrosis.

Dataset Information

Protease activated receptor 2 (PAR2) activation causes migraine-like pain behaviors in mice.

Publications

Protease activated receptor 2 (PAR2) activation causes migraine-like pain behaviors in mice.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets