Showing papers on "Protease-activated receptor 2 published in 2023"
TL;DR: In this article , a synthetic peptide SLIGRL-NH2 (SLIGRL) can activate PAR2, while FSLLRY-NH 2 (FSLLRY) is an antagonist.
Abstract: Protease-activated receptor 2 (PAR2), a type of G protein-coupled receptor (GPCR), plays a significant role in pathophysiological conditions such as inflammation. A synthetic peptide SLIGRL-NH2 (SLIGRL) can activate PAR2, while FSLLRY-NH2 (FSLLRY) is an antagonist. A previous study showed that SLIGRL activates both PAR2 and mas-related G protein-coupled receptor C11 (MrgprC11), a different type of GPCR expressed in sensory neurons. However, the impact of FSLLRY on MrgprC11 and its human ortholog MRGPRX1 was not verified. Hence, the present study aims to verify the effect of FSLLRY on MrgprC11 and MRGPRX1.The calcium imaging technique was applied to determine the effect of FSLLRY in HEK293T cells expressing MrgprC11/MRGPRX1 or dorsal root ganglia (DRG) neurons. Scratching behavior was also investigated in wild-type and PAR2 knockout mice after injecting FSLLRY.It was surprisingly discovered that FSLLRY specifically activates MrgprC11 in a dose-dependent manner, but not other MRGPR subtypes. Furthermore, FSLLRY also moderately activated MRGPRX1. FSLLRY stimulates downstream pathways including Gαq/11, phospholipase C, IP3 receptor, and TRPC ion channels to evoke an increase in the intracellular calcium levels. The molecular docking analysis predicted that FSLLRY interacts with the orthosteric binding pocket of MrgprC11 and MRGPRX1. Finally, FSLLRY activated primary cultures of mouse sensory neurons, and induced scratching behaviors in mice.The present study has revealed that FSLLRY is capable of triggering itch sensation through activation of MrgprC11. This finding highlights the importance of considering the unexpected activation of MRGPRs in future therapeutic approaches aimed at the inhibition of PAR2.
TL;DR: In this paper , the authors developed full and biased PAR2 antagonists and tested their efficacy in acute allergen-induced asthma mouse models, and to a lesser extent, mucus overproduction.
Abstract: Biased signaling in G protein-coupled receptors (GPCRs) has emerged as a target for drug development. Protease-activated receptor-2 (PAR2) is a GPCR present in the airway epithelium with biased signaling that has been shown to trigger both detrimental effects [airway hyperresponsiveness (AHR), inflammation, mucus overproduction] and beneficial effects (bronchorelaxation) associated with allergen-induced asthma. These dual effects have been shown to be dictated by the two primary signaling pathways downstream of PAR2 activation: Gαq/Ca 2+ signaling is associated with bronchorelaxation, and β-arrestin/MAPK signaling is associated with AHR, inflammation and mucus overproduction. We have developed full (C391 which antagonizes Gαq/Ca 2+ and β-arrestin/MAPK signaling) and biased (C781 which antagonizes β-arrestin/MAPK signaling) antagonists of PAR2 and tested their efficacy in acute allergen-induced asthma mouse models. Both full and β-arrestin/MAPK signaling compounds attenuated AHR and inflammation in mouse models, and to a lesser extent, mucus overproduction. In a human bronchial model, the full PAR2 antagonist C391 prevented PAR2- dependent bronchial relaxation while the biased PAR2 antagonist C781 did not. Antagonism by C781 and other biased PAR2 antagonists can fine tune and effectively improve safety profiles for drug development in asthma treatment. Grants from the National Institute of Health (NS098826, AI140257, HL16024, HL152942) This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.