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G protein-coupled receptors (GPCRs) regulate many pathophysiological processes and are major therapeutic targets. The impact of disease on the subcellular distribution and function of GPCRs is poorly understood. We investigated trafficking and signaling of protease-activated receptor 2 (PAR2) in colitis. To localize PAR2 and assess redistribution during disease, we generated knockin mice expressing PAR2 fused to monomeric ultrastable green fluorescent protein (muGFP). PAR2-muGFP signaled and trafficked normally. PAR2 messenger RNA was detected at similar levels in Par2-mugfp and wild-type mice. Immunostaining with a GFP antibody and RNAScope in situ hybridization using F2rl1 (PAR2) and Gfp probes revealed that PAR2-muGFP was expressed in epithelial cells of the small and large intestine and in subsets of enteric and dorsal root ganglia neurons. In healthy mice, PAR2-muGFP was prominently localized to the basolateral membrane of colonocytes. In mice with colitis, PAR2-muGFP was depleted from the plasma membrane of colonocytes and redistributed to early endosomes, consistent with generation of proinflammatory proteases that activate PAR2 PAR2 agonists stimulated endocytosis of PAR2 and recruitment of Gαq, Gαi, and β-arrestin to early endosomes of T84 colon carcinoma cells. PAR2 agonists increased paracellular permeability of colonic epithelial cells, induced colonic inflammation and hyperalgesia in mice, and stimulated proinflammatory cytokine release from segments of human colon. Knockdown of dynamin-2 (Dnm2), the major colonocyte isoform, and Dnm inhibition attenuated PAR2 endocytosis, signaling complex assembly and colonic inflammation and hyperalgesia. Thus, PAR2 endocytosis sustains protease-evoked inflammation and nociception and PAR2 in endosomes is a potential therapeutic target for colitis.

It has been proposed that autistic people experience a temporal distortion whereby the temporal binding window of multisensory integration is extended. Research to date has focused on autistic children so whether these differences persist into adulthood remains unknown. In addition, the possibility that the previous observations have arisen from between-group differences in response bias, rather than perceptual differences, has not been addressed. Participants completed simultaneity judgements of audiovisual speech stimuli across a range of stimulus-onset asynchronies. Response times and accuracy data were fitted to a drift-diffusion model so that the drift rate (a measure of processing efficiency) and starting point (response bias) could be estimated. In Experiment 1, we tested a sample of non-autistic adults who completed the Autism Quotient questionnaire. Autism Quotient score was not correlated with either drift rate or response bias, nor were there between-group differences when splitting based on the first and third quantiles of scores. In Experiment 2, we compared the performance of autistic with a group of non-autistic adults. There were no between-group differences in either drift rate or starting point. The results of this study do not support the previous suggestion that autistic people have an extended temporal binding window for audiovisual speech. In addition, exploratory analysis revealed that operationalising the temporal binding window in different ways influenced whether a group difference was observed, which is an important consideration for future work. [ABSTRACT FROM AUTHOR]

Gastrointestinal motility is tightly regulated by the enteric nervous system (ENS). Disruption of coordinated enteric nervous system activity can result in dysmotility. Pharmacological treatment options for dysmotility include targeting of G protein‐coupled receptors (GPCRs) expressed by neurons of the enteric nervous system. Current GPCR‐targeting drugs for motility disorders bind to the highly conserved endogenous ligand‐binding site and promote indiscriminate activation or inhibition of the target receptor throughout the body. This can be associated with significant side‐effect liability and a loss of physiological tone. Allosteric modulators of GPCRs bind to a distinct site from the endogenous ligand, which is typically less conserved across multiple receptor subtypes and can modulate endogenous ligand signalling. Allosteric modulation of GPCRs that are important for enteric nervous system function may provide effective relief from motility disorders while limiting side‐effects. This review will focus on how allosteric modulators of GPCRs may influence gastrointestinal motility, using 5‐hydroxytryptamine (5‐HT), acetylcholine (ACh) and opioid receptors as examples. LINKED ARTICLES: This article is part of a themed issue Therapeutic Targeting of G Protein‐Coupled Receptors: hot topics from the Australasian Society of Clinical and Experimental Pharmacologists and Toxicologists 2021 Virtual Annual Scientific Meeting. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v181.14/issuetoc [ABSTRACT FROM AUTHOR]

Post-diagnostic support for autistic adults in the United Kingdom is geographically inequitable and, in general, considered inadequate. This results in autistic adults facing unnecessary challenges and wide-ranging poor outcomes. A modified Delphi study sought to establish autistic adults' priorities for optimal provision of post-diagnostic support. The study was co-designed with 10 autistic adults across a series of three online workshops. Forty-three autistic adults, who had received their diagnosis in adulthood, completed a series of three online questionnaires through which 153 support priorities were identified. In a fourth questionnaire round, completed by 139 autistic adults, 24 priorities reached or exceeded a consensus threshold of 80% agreement that the item specified an important element of post-diagnostic support. Participants ranked access to support where they live, training of professionals, support to process the impact of a late diagnosis, use of their preferred mode of contact and an individualised support plan as their key priorities for post-diagnostic support. The whole priority list provides a clear and practical articulation of what autistic adults want from post-diagnostic support. This should be used by policymakers and service providers in the United Kingdom to ensure that post-diagnostic support for autistic adults is fit for purpose. Autistic adults in the United Kingdom report that support for themselves and their peers is not suitable for their needs. There has been an increase in adults receiving an autism diagnosis, which many have reported as having a positive impact on their lives. However, the lack of support and understanding after diagnosis, combined with long wait times for an assessment to obtain a diagnosis and to access follow-on support, is having a negative impact on people's lives. This study took place to find out what support autistic people need and want after receiving their diagnosis. It was co-designed with a group of 10 autistic adults which means that the researchers and group members collaboratively designed the research. For the study, 43 autistic adults, diagnosed aged 18 or older, completed three questionnaires. A fourth questionnaire followed that was completed by 139 autistic people who received their diagnosis in adulthood. These questionnaires aimed to help people identify their own priorities when it came to the support they would have liked to receive after being given their autism diagnosis. Participants ranked access to support where they live, training of professionals, support to process the impact of a late diagnosis, use of their preferred mode of contact and a personalised support plan as their top priorities. This demonstrates that local support is highly valued by autistic adults, as are well-trained professionals who offer a range of contact options, support to process a late-in-life autism diagnosis and help to develop and implement support plans. [ABSTRACT FROM AUTHOR]