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1.
J Relig Health ; 63(1): 289-308, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38252390

RESUMEN

A module to explore perspectives on chaplaincy services was included in an online enterprise survey randomly distributed to members of the Australian Defence Force (ADF) during 2021. Up to eight questions were answered by 2783 active military personnel relating to their perception of chaplain activities and the impact of chaplaincy services. Of those military participants answering the question on religious status (n = 1116), a total of 71.6% (n = 799) of respondents identified as non-religious while 28.4% (n = 317) identified as holding a religious affiliation. Approximately 44.2% (n = 1230) of participants had sought support from a chaplain, of which 85.3% (n = 1049) found chaplaincy care to be satisfactory or very satisfactory. While the data suggest there is a lack of clarity around the multiple roles undertaken by chaplaincy, nevertheless respondents were just as likely to prefer chaplains for personal support (24.0%), as they were to seek help from non-chaplaincy personnel such as a non-ADF counsellor (23.2%), their workplace supervisor (23.1%) or a psychologist (21.8%). This evidence affirms that the spiritual care provided by military chaplaincy remains one of several preferred choices and thus a valued part of the holistic care provided by the ADF to support the health and wellbeing of its members.


Asunto(s)
Servicio de Capellanía en Hospital , Personal Militar , Cuidado Pastoral , Terapias Espirituales , Humanos , Estudios Transversales , Australia , Espiritualidad , Clero
2.
Am J Respir Cell Mol Biol ; 69(2): 182-196, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37098022

RESUMEN

Asthma is a heterogeneous chronic airway disease with an unmet need for improved therapeutics in uncontrolled severe disease. The calcium-sensing receptor (CaSR) is a G protein-coupled receptor upregulated in asthma. The CaSR agonist, spermine, is also increased in asthmatic airways and contributes to bronchoconstriction. CaSR negative allosteric modulators (NAMs) oppose chronic airway inflammation, remodeling, and hyperresponsiveness in murine and guinea pig asthma models, but whether CaSR NAMs are effective acute bronchodilators compared with standard of care has not yet been established. Furthermore, the ability of different classes of NAMs to inhibit spermine-induced CaSR signaling or methacholine (MCh)-induced airway contraction has not been quantified. Here, we show CaSR NAMs differentially inhibit spermine-induced intracellular calcium mobilization and inositol monophosphate accumulation in HEK293 cells stably expressing the CaSR. NAMs reverse MCh-mediated airway contraction in mouse precision-cut lung slices with similar maximal relaxation compared with the standard treatment, salbutamol. Of note, the bronchodilator effects of CaSR NAMs are maintained under conditions of ß2-adrenergic receptor desensitization when salbutamol efficacy is abolished. Furthermore, overnight treatment with some, but not all, CaSR NAMs prevents MCh-mediated bronchoconstriction. These findings further support the CaSR as a putative drug target and NAMs as alternative or adjunct bronchodilators in asthma.


Asunto(s)
Asma , Broncodilatadores , Ratones , Humanos , Animales , Cobayas , Broncodilatadores/farmacología , Receptores Sensibles al Calcio/agonistas , Receptores Sensibles al Calcio/metabolismo , Células HEK293 , Espermina/uso terapéutico , Asma/tratamiento farmacológico , Asma/metabolismo , Albuterol/farmacología , Cloruro de Metacolina/farmacología
3.
Pharmacol Rev ; 72(3): 558-604, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32467152

RESUMEN

The calcium-sensing receptor (CaSR) is a class C G protein-coupled receptor that responds to multiple endogenous agonists and allosteric modulators, including divalent and trivalent cations, L-amino acids, γ-glutamyl peptides, polyamines, polycationic peptides, and protons. The CaSR plays a critical role in extracellular calcium (Ca2+ o) homeostasis, as demonstrated by the many naturally occurring mutations in the CaSR or its signaling partners that cause Ca2+ o homeostasis disorders. However, CaSR tissue expression in mammals is broad and includes tissues unrelated to Ca2+ o homeostasis, in which it, for example, regulates the secretion of digestive hormones, airway constriction, cardiovascular effects, cellular differentiation, and proliferation. Thus, although the CaSR is targeted clinically by the positive allosteric modulators (PAMs) cinacalcet, evocalcet, and etelcalcetide in hyperparathyroidism, it is also a putative therapeutic target in diabetes, asthma, cardiovascular disease, and cancer. The CaSR is somewhat unique in possessing multiple ligand binding sites, including at least five putative sites for the "orthosteric" agonist Ca2+ o, an allosteric site for endogenous L-amino acids, two further allosteric sites for small molecules and the peptide PAM, etelcalcetide, and additional sites for other cations and anions. The CaSR is promiscuous in its G protein-coupling preferences, and signals via Gq/11, Gi/o, potentially G12/13, and even Gs in some cell types. Not surprisingly, the CaSR is subject to biased agonism, in which distinct ligands preferentially stimulate a subset of the CaSR's possible signaling responses, to the exclusion of others. The CaSR thus serves as a model receptor to study natural bias and allostery. SIGNIFICANCE STATEMENT: The calcium-sensing receptor (CaSR) is a complex G protein-coupled receptor that possesses multiple orthosteric and allosteric binding sites, is subject to biased signaling via several different G proteins, and has numerous (patho)physiological roles. Understanding the complexities of CaSR structure, function, and biology will aid future drug discovery efforts seeking to target this receptor for a diversity of diseases. This review summarizes what is known to date regarding key structural, pharmacological, and physiological features of the CaSR.


Asunto(s)
Receptores Sensibles al Calcio/agonistas , Receptores Sensibles al Calcio/antagonistas & inhibidores , Animales , Sitios de Unión , Proteínas de Unión al GTP/metabolismo , Humanos , Modelos Moleculares , Receptores Sensibles al Calcio/química , Receptores Sensibles al Calcio/metabolismo , Transducción de Señal , Bibliotecas de Moléculas Pequeñas/farmacología
4.
J Relig Health ; 62(1): 98-116, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36402854

RESUMEN

Chaplains are embedded in several ambulance services across Australia, however as Australia's religiosity is currently in decline and questions are being asked about retaining chaplains, little is actually known about their role and value within Ambulance services. The aim of this paper is to present the key findings from interviews with chaplains about their role and value of being ambulance chaplains. These findings are then compared with those of paramedics derived from an earlier phase of this study. Thirteen chaplains participated in semi-structured interviews, and data were analysed using framework analysis. The results indicated that ambulance chaplains provided paramedic-centred emotional and spiritual care through proactively and reactively supporting paramedics in their work. Chaplains saw value in their relational approach which facilitated trust and access, did not seek to 'fix' or diagnose but instead offered physical and emotional presence, and promoted supportive conversations. Chaplains and paramedics valued operationally trained and equipped ambulance chaplains who provided a relational, around the clock, 'frontline' staff support presence in paramedic workplaces, regardless of the paramedic's personal religious/spiritual beliefs.


Asunto(s)
Ambulancias , Clero , Humanos , Clero/psicología , Paramédico , Australia , Emociones
5.
Nature ; 531(7594): 335-40, 2016 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-26958838

RESUMEN

Muscarinic M1-M5 acetylcholine receptors are G-protein-coupled receptors that regulate many vital functions of the central and peripheral nervous systems. In particular, the M1 and M4 receptor subtypes have emerged as attractive drug targets for treatments of neurological disorders, such as Alzheimer's disease and schizophrenia, but the high conservation of the acetylcholine-binding pocket has spurred current research into targeting allosteric sites on these receptors. Here we report the crystal structures of the M1 and M4 muscarinic receptors bound to the inverse agonist, tiotropium. Comparison of these structures with each other, as well as with the previously reported M2 and M3 receptor structures, reveals differences in the orthosteric and allosteric binding sites that contribute to a role in drug selectivity at this important receptor family. We also report identification of a cluster of residues that form a network linking the orthosteric and allosteric sites of the M4 receptor, which provides new insight into how allosteric modulation may be transmitted between the two spatially distinct domains.


Asunto(s)
Receptor Muscarínico M1/química , Receptor Muscarínico M4/química , Acetilcolina/metabolismo , Regulación Alostérica/efectos de los fármacos , Sitio Alostérico/efectos de los fármacos , Enfermedad de Alzheimer , Cristalización , Cristalografía por Rayos X , Agonismo Inverso de Drogas , Humanos , Modelos Moleculares , Ácidos Nicotínicos/metabolismo , Ácidos Nicotínicos/farmacología , Receptor Muscarínico M1/metabolismo , Receptor Muscarínico M4/metabolismo , Esquizofrenia , Electricidad Estática , Especificidad por Sustrato , Propiedades de Superficie , Tiofenos/metabolismo , Tiofenos/farmacología , Bromuro de Tiotropio/farmacología
6.
J Relig Health ; 61(2): 929-947, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34694550

RESUMEN

Chaplains are employed by ambulance services in many states across Australia as one element in a suite of initiatives to support the health and wellness of paramedics. The aim of this paper is to present key findings from a study that explored paramedic perspectives on the role and value of chaplains in the ambulance service. Seventeen paramedics participated in semi-structured interviews. Data were analysed using framework analysis. Two themes were identified: scope of the chaplain's role and organisational factors influencing the chaplain's role. Paramedics highly valued what they believed to be proactive and reactive support provided by ambulance chaplains, regardless of paramedics' personal spiritual or religious beliefs.


Asunto(s)
Clero , Auxiliares de Urgencia , Técnicos Medios en Salud , Ambulancias , Australia , Humanos
7.
J Relig Health ; 61(2): 1155-1182, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35059963

RESUMEN

Chaplains have been embedded in military settings for over a millennium. In recent years however, the decline in spiritual/religious (S/R) affiliation of military personnel across Western cultures has led to some commentators questioning the utilization of religious chaplains by defence personnel. This scoping review maps the literature on S/R and non-S/R factors that influence utilizing military chaplains-with a particular emphasis on the Australian military context. A systematic scoping review of tertiary literature databases using Arksey and O'Malley (2003) and Joanna Briggs Institute methodologies (JBI, 2021), revealed a total of 33 articles meeting the inclusion criteria. Results fell into three broad categories: (i) how personal religious views influence utilization of military chaplaincy, (ii) barriers and enablers to personnel utilizing military chaplains, and (iii) the impact of chaplaincy. Despite the current reduction in religiosity in Western society, findings from this scoping review suggest there is little evidence that low religiosity among military personnel forms a significant barrier to utilizing chaplaincy services. To the contrary, the literature revealed that chaplains provide trusted, confidential, and holistic support for military personnel that if diminished or compromised would leave a substantial gap in staff well-being services.


Asunto(s)
Personal Militar , Cuidado Pastoral , Australia , Clero , Humanos , Cuidado Pastoral/métodos
8.
Mol Pharmacol ; 97(1): 35-45, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31704718

RESUMEN

Current operational models of agonism and allosterism quantify ligand actions at receptors where agonist concentration-response relationships are nonhyperbolic by introduction of a transducer slope that relates receptor occupancy to response. However, for some receptors nonhyperbolic concentration-response relationships arise from multiple endogenous agonist molecules binding to a receptor in a cooperative manner. Thus, we developed operational models of agonism in systems with cooperative agonist binding and evaluated the models by simulating data describing agonist effects. The models were validated by analyzing experimental data demonstrating the effects of agonists and allosteric modulators at receptors where agonist binding follows hyperbolic (M4 muscarinic acetylcholine receptors) or nonhyperbolic relationships (metabotropic glutamate receptor 5 and calcium-sensing receptor). For hyperbolic agonist concentration-response relationships, no differences in estimates of ligand affinity, efficacy, or cooperativity were observed when the slope was assigned to either a transducer slope or agonist binding slope. In contrast, for receptors with nonhyperbolic agonist concentration-response relationships, estimates of ligand affinity, efficacy, or cooperativity varied depending on the assignment of the slope. The extent of this variation depended on the magnitude of the slope value and agonist efficacy, and for allosteric modulators on the magnitude of cooperativity. The modified operational models described herein are well suited to analyzing agonist and modulator interactions at receptors that bind multiple orthosteric agonists in a cooperative manner. Accounting for cooperative agonist binding is essential to accurately quantify agonist and drug actions. SIGNIFICANCE STATEMENT: Some orthosteric agonists bind to multiple sites on a receptor, but current analytical methods to characterize such interactions are limited. Herein, we develop and validate operational models of agonism and allosterism for receptors with multiple orthosteric binding sites, and demonstrate that such models are essential to accurately quantify agonist and drug actions. These findings have important implications for the discovery and development of drugs targeting receptors such as the calcium-sensing receptor, which binds at least five calcium ions.


Asunto(s)
Sitios de Unión/efectos de los fármacos , Ionóforos de Calcio/farmacología , Agonismo de Drogas , Modelos Biológicos , Receptores Sensibles al Calcio/agonistas , Regulación Alostérica/efectos de los fármacos , Calcio/metabolismo , Simulación por Computador , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Células HEK293 , Humanos , Ligandos , Receptor del Glutamato Metabotropico 5/agonistas , Receptor del Glutamato Metabotropico 5/química , Receptor del Glutamato Metabotropico 5/metabolismo , Receptor Muscarínico M4/agonistas , Receptor Muscarínico M4/química , Receptor Muscarínico M4/metabolismo , Receptores Sensibles al Calcio/química , Receptores Sensibles al Calcio/metabolismo
9.
J Neurochem ; 151(3): 301-315, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31376155

RESUMEN

Allosteric modulators of metabotropic glutamate receptor 5 (mGlu5 ) are a promising therapeutic strategy for a number of neurological disorders. Multiple mGlu5 -positive allosteric modulator (PAM) chemotypes have been discovered that act as either pure PAMs or as PAM-agonists in recombinant and native cells. While these compounds have been tested in paradigms of receptor activation, their effects on receptor regulatory processes are largely unknown. In this study, acute desensitization of mGlu5 mediated intracellular calcium mobilization by structurally diverse mGlu5 orthosteric and allosteric ligands was assessed in human embryonic kidney 293 cells and primary murine neuronal cultures from both striatum and cortex. We aimed to determine the intrinsic efficacy and modulatory capacity of diverse mGlu5 PAMs [(R)-5-((3-fluorophenyl)ethynyl)-N-(3-hydroxy-3-methylbutan-2-yl)picolinamide (VU0424465), N-cyclobutyl-6-((3-fluorophenyl)ethynyl)picolinamide (VU0360172), 1-(4-(2,4-difluorophenyl)piperazin-1-yl)-2-((4-fluorobenzyl)oxy)ethanone (DPFE), ((4-fluorophenyl) (2-(phenoxymethyl)-6,7-dihydrooxazolo[5,4-c]pyridin-5(4H)-yl)methanone) (VU0409551), 3-Cyano-N-(1,3-diphenyl-1H-pyrazol-5-yl)benzamide (CDPPB)] on receptor desensitization and whether cellular context influences receptor regulatory processes. Only VU0424465 and VU0409551 induced desensitization alone in human embryonic kidney 293-mGlu5 cells, while all PAMs enhanced (S)-3,5-dihydroxyphenylglycine (DHPG)-induced desensitization. All mGlu5 PAMs induced receptor desensitization alone and enhanced DHPG-induced desensitization in striatal neurons. VU0424465 and VU0360172 were the only PAMs that induced desensitization alone in cortical neurons. With the exception of (CDPPB), PAMs enhanced DHPG-induced desensitization in cortical neurons. Moreover, differential apparent affinities, efficacies, and cooperativities with DHPG were observed for VU0360172, VU0409551, and VU0424465 when comparing receptor activation and desensitization in a cell type-dependent manner. These data indicate that biased mGlu5 allosteric modulator pharmacology extends to receptor regulatory processes in a tissue dependent manner, adding yet another layer of complexity to rational mGlu5 drug discovery.


Asunto(s)
Receptor del Glutamato Metabotropico 5/efectos de los fármacos , Regulación Alostérica/efectos de los fármacos , Animales , Benzamidas/farmacología , Cuerpo Estriado/efectos de los fármacos , Cuerpo Estriado/metabolismo , Humanos , Ratones , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Oxazoles/farmacología , Ácidos Picolínicos/farmacología , Piridinas/farmacología , Receptor del Glutamato Metabotropico 5/metabolismo
10.
Mol Pharmacol ; 93(5): 504-514, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29514854

RESUMEN

Numerous positive and negative allosteric modulators (PAMs and NAMs) of class C G protein-coupled receptors (GPCRs) have been developed as valuable preclinical pharmacologic tools and therapeutic agents. Although many class C GPCR allosteric modulators have undergone subtype selectivity screening, most assay paradigms have failed to perform rigorous pharmacologic assessment. Using mGlu5 as a representative class C GPCR, we tested the hypothesis that allosteric modulator selectivity was based on cooperativity rather than affinity. Specifically, we aimed to identify ligands that bound to mGlu5 but exhibited neutral cooperativity with mGlu5 agonists. We additionally evaluated the potential for these ligands to exhibit biased pharmacology. Radioligand binding, intracellular calcium (iCa2+) mobilization, and inositol monophosphate (IP1) accumulation assays were undertaken in human embryonic kidney cells expressing low levels of rat mGlu5 (HEK293A-mGlu5-low) for diverse allosteric chemotypes. Numerous "non-mGlu5" class C GPCR allosteric modulators incompletely displaced allosteric mGlu5 radioligand [3H]methoxy-PEPy binding, consistent with a negative allosteric interaction. Affinity estimates for CPCCOEt (mGlu1 ligand), PHCCC (mGlu4 ligand), GS39783 (GABAB ligand), AZ12216052 (mGlu8 ligand), and CGP7930 (GABAB ligand) at mGlu5 were within 10-fold of their target receptor. Most class C GPCR allosteric modulators had neutral cooperativity with both orthosteric and allosteric mGlu5 agonists in functional assays; however, NPS2143 (calcium-sensing receptor (CaSR) NAM), cinacalcet (CaSR PAM), CGP7930, and AZ12216052 were partial mGlu5 agonists for IP1 accumulation, but not iCa2+ mobilization. By using mGlu5 as a model class C GPCR, we find that for many class C GPCR allosteric modulators, subtype selectivity is driven by cooperativity and misinterpreted owing to unappreciated bias.


Asunto(s)
Receptor del Glutamato Metabotropico 5/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Regulación Alostérica , Animales , Calcio/metabolismo , Corteza Cerebral/citología , Corteza Cerebral/metabolismo , Femenino , Células HEK293 , Humanos , Fosfatos de Inositol/metabolismo , Ligandos , Ratones , Neuronas/metabolismo , Ensayo de Unión Radioligante , Ratas , Tritio
11.
Mol Pharmacol ; 93(6): 619-630, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29636377

RESUMEN

Calcium sensing receptor (CaSR) positive allosteric modulators (PAMs) are therapeutically important. However, few are approved for clinical use, in part due to complexities in assessing allostery at a receptor where the endogenous agonist (extracellular calcium) is present in all biologic fluids. Such complexity impedes efforts to quantify and optimize allosteric drug parameters (affinity, cooperativity, and efficacy) that dictate PAM structure-activity relationships (SARs). Furthermore, an underappreciation of the structural mechanisms underlying CaSR activation hinders predictions of how PAM SAR relates to in vitro and in vivo activity. Herein, we combined site-directed mutagenesis and calcium mobilization assays with analytical pharmacology to compare modes of PAM binding, positive modulation, and agonism. We demonstrate that 3-(2-chlorophenyl)-N-((1R)-1-(3-methoxyphenyl)ethyl)-1-propanamine (NPS R568) binds to a 7 transmembrane domain (7TM) cavity common to class C G protein-coupled receptors and used by (αR)-(-)-α-methyl-N-[3-[3-[trifluoromethylphenyl]propyl]-1-napthalenemethanamine (cinacalcet) and 1-benzothiazol-2-yl-1-(2,4-dimethylphenyl)-ethanol (AC265347); however, there are subtle distinctions in the contribution of select residues to the binding and transmission of cooperativity by PAMs. Furthermore, we reveal some common activation mechanisms used by different CaSR activators, but also demonstrate some differential contributions of residues within the 7TM bundle and extracellular loops to the efficacy of the PAM-agonist, AC265347, versus cooperativity. Finally, we show that PAMS potentiate the affinity of divalent cations. Our results support the existence of both global and ligand-specific CaSR activation mechanisms and reveal that allosteric agonism is mediated in part via distinct mechanisms to positive modulation.


Asunto(s)
Calcio/metabolismo , Receptores Sensibles al Calcio/metabolismo , Regulación Alostérica/efectos de los fármacos , Regulación Alostérica/fisiología , Sitio Alostérico/fisiología , Secuencia de Aminoácidos , Línea Celular , Cinacalcet/farmacología , Humanos , Ligandos , Mutagénesis Sitio-Dirigida/métodos , Fenetilaminas/farmacología , Propilaminas/farmacología , Relación Estructura-Actividad
12.
J Pharmacol Exp Ther ; 367(2): 335-347, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30104322

RESUMEN

Renal podocyte survival depends upon the dynamic regulation of a complex cell architecture that links the glomerular basement membrane to integrins, ion channels, and receptors. Alport syndrome is a heritable chronic kidney disease where mutations in α3, α4, or α5 collagen genes promote podocyte death. In rodent models of renal failure, activation of the calcium-sensing receptor (CaSR) can protect podocytes from stress-related death. In this study, we assessed CaSR function in podocyte-like cells derived from induced-pluripotent stem cells from two patients with Alport Syndrome (AS1 & AS2) and a renal disease free individual [normal human mesangial cell (NHMC)], as well as a human immortalized podocyte-like (HIP) cell line. Extracellular calcium elicited concentration-dependent elevations of intracellular calcium in all podocyte-like cells. NHMC and HIP, but not AS1 or AS2 podocyte-like cells, also showed acute reductions in intracellular calcium prior to elevation. In NHMC podocyte-like cells this acute reduction was blocked by the large-conductance potassium channel (KCNMA1) inhibitors iberiotoxin (10 nM) and tetraethylammonium (5 mM), as well as the focal adhesion kinase inhibitor PF562271 (N-methyl-N-(3-((2-(2-oxo-2,3-dihydro-1H-indol-5-ylamino)-5-trifluoromethyl-pyrimidin-4-ylamino)-methyl)-pyridin-2-yl)-methanesulfonamide, 10 nM). Quantitative polymerase chain reaction (qPCR) and immunolabeling showed the presence of KCNMA1 transcript and protein in all podocyte-like cells tested. Cultivation of AS1 podocytes on decellularized plates of NHMC podocyte-like cells partially restored acute reductions in intracellular calcium in response to extracellular calcium. We conclude that the AS patient-derived podocyte-like cells used in this study showed dysfunctional integrin signaling and potassium channel function, which may contribute to podocyte death seen in Alport syndrome.


Asunto(s)
Células Madre Pluripotentes Inducidas/metabolismo , Nefritis Hereditaria/metabolismo , Podocitos/metabolismo , Canales de Potasio/metabolismo , Adolescente , Calcio/metabolismo , Línea Celular , Colágeno Tipo IV/metabolismo , Proteína-Tirosina Quinasas de Adhesión Focal/metabolismo , Membrana Basal Glomerular/metabolismo , Humanos , Subunidades alfa de los Canales de Potasio de Gran Conductancia Activados por Calcio/metabolismo , Masculino , Persona de Mediana Edad , Fenotipo , Receptores Sensibles al Calcio/metabolismo , Transducción de Señal/fisiología
13.
Clin Sci (Lond) ; 132(21): 2323-2338, 2018 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-30389826

RESUMEN

Metabotropic glutamate receptors belong to class C G-protein-coupled receptors and consist of eight subtypes that are ubiquitously expressed throughout the central nervous system. In recent years, the metabotropic glutamate receptor subtype 5 (mGlu5) has emerged as a promising target for a broad range of psychiatric and neurological disorders. Drug discovery programs targetting mGlu5 are primarily focused on development of allosteric modulators that interact with sites distinct from the endogenous agonist glutamate. Significant efforts have seen mGlu5 allosteric modulators progress into clinical trials; however, recent failures due to lack of efficacy or adverse effects indicate a need for a better understanding of the functional consequences of mGlu5 allosteric modulation. Biased agonism is an interrelated phenomenon to allosterism, describing how different ligands acting through the same receptor can differentially influence signaling to distinct transducers and pathways. Emerging evidence demonstrates that allosteric modulators can induce biased pharmacology at the level of intrinsic agonism as well as through differential modulation of orthosteric agonist-signaling pathways. Here, we present key considerations in the discovery and development of mGlu5 allosteric modulators and the opportunities and pitfalls offered by biased agonism and modulation.


Asunto(s)
Fármacos del Sistema Nervioso Central/farmacología , Sistema Nervioso Central/efectos de los fármacos , Agonistas de Aminoácidos Excitadores/farmacología , Receptor del Glutamato Metabotropico 5/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Animales , Sitios de Unión , Sistema Nervioso Central/metabolismo , Fármacos del Sistema Nervioso Central/química , Fármacos del Sistema Nervioso Central/metabolismo , Agonistas de Aminoácidos Excitadores/química , Agonistas de Aminoácidos Excitadores/metabolismo , Ácido Glutámico/metabolismo , Humanos , Ligandos , Unión Proteica , Conformación Proteica , Receptor del Glutamato Metabotropico 5/química , Receptor del Glutamato Metabotropico 5/metabolismo , Relación Estructura-Actividad
14.
Pharmacol Res ; 116: 105-118, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27965032

RESUMEN

Class C G protein-coupled receptors (GPCRs) recognise diverse extracellular stimuli and are highly tractable drug targets for a host of different psychiatric, neurological and metabolic disorders. Discovery efforts focussed on allosteric modulators for Class C GPCRs have been highly fruitful, with diverse chemotypes identified for multiple Class C members. Indeed, a positive allosteric modulator of the calcium-sensing receptor, cinacalcet, was one of the first GPCR allosteric ligands to enter the clinic. Despite this success, allosteric modulator discovery and development remains challenging. In particular, the prevalence of probe dependence and biased pharmacology (both agonism and modulation) adds considerable complexity. Recent studies have yielded new insights into the structural basis for allosteric interactions at Class C GPCRs. This information coupled with rigorous analytical approaches has increased our understanding of the rich molecular pharmacology and biology for Class C GPCRs.


Asunto(s)
Regulación Alostérica/fisiología , Receptores Acoplados a Proteínas G/metabolismo , Animales , Humanos , Receptores Sensibles al Calcio/metabolismo , Relación Estructura-Actividad
15.
Mol Pharmacol ; 88(2): 368-79, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26044547

RESUMEN

CB1 cannabinoid receptors (CB1Rs) are attractive therapeutic targets for numerous central nervous system disorders. However, clinical application of cannabinoid ligands has been hampered owing to their adverse on-target effects. Ligand-biased signaling from, and allosteric modulation of, CB1Rs offer pharmacological approaches that may enable the development of improved CB1R drugs, through modulation of only therapeutically desirable CB1R signaling pathways. There is growing evidence that CB1Rs are subject to ligand-biased signaling and allosterism. Therefore, in the present study, we quantified ligand-biased signaling and allosteric modulation at CB1Rs. Cannabinoid agonists displayed distinct biased signaling profiles at CB1Rs. For instance, whereas 2-arachidonylglycerol and WIN55,212-2 [(R)-(+)-[2,3-dihydro-5-methyl-3-(4-morpholinylmethyl)pyrrolo[1,2,3-de]-1,4-benzoxazin-6-yl]-1-napthalenylmethanone] showed little preference for inhibition of cAMP and phosphorylation of extracellular signal-regulated kinase 1/2 (pERK1/2), N-arachidonoylethanolamine (anandamide), methanandamide, CP55940 [2-[(1R,2R,5R)-5-hydroxy-2-(3-hydroxypropyl)cyclohexyl]-5-(2-methyloctan-2-yl)phenol], and HU-210 [11-hydroxy-Δ(8)-THC-dimethylheptyl] were biased toward cAMP inhibition. The small-molecule allosteric modulator Org27569 [5-chloro-3-ethyl-1H-indole-2-carboxylic acid [2-(4-piperidin-1-yl-phenyl)ethyl]amide] displayed biased allosteric effects by blocking cAMP inhibition mediated by all cannabinoid ligands tested, at the same time having little or no effect on ERK1/2 phosphorylation mediated by a subset of these ligands. Org27569 also displayed negative binding cooperativity with [(3)H]SR141716A [5-(4-chlorophenyl)-1-(2,4-dichloro-phenyl)-4-methyl-N-(piperidin-1-yl)-1H-pyrazole-3-carboxamide]; however, it had minimal effects on binding of cannabinoid agonists. Furthermore, we highlight the need to validate the reported allosteric effects of the endogenous ligands lipoxin A4 and pregnenolone at CB1Rs. Pregnenolone but not lipoxin A4 displaced [(3)H]SR141716A, but there was no functional interaction between either of these ligands and cannabinoid agonists. This study demonstrates an approach to validating and quantifying ligand-biased signaling and allosteric modulation at CB1Rs, revealing ligand-biased "fingerprints" that may ultimately allow the development of improved CB1R-targeted therapies.


Asunto(s)
Agonistas de Receptores de Cannabinoides/farmacología , Indoles/farmacología , Piperidinas/farmacología , Pirazoles/farmacología , Receptor Cannabinoide CB1/metabolismo , Regulación Alostérica , Animales , Benzoxazinas/farmacología , Células CHO , Cricetulus , Ciclohexanoles/farmacología , Dronabinol/análogos & derivados , Dronabinol/farmacología , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Morfolinas/farmacología , Naftalenos/farmacología , Fosforilación , Receptor Cannabinoide CB1/química , Rimonabant , Transducción de Señal/efectos de los fármacos
16.
J Health Care Chaplain ; 30(3): 202-225, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38574262

RESUMEN

Ambulance staff wellbeing programs aim to support the bio-psycho-social and sometimes spiritual needs of paramedics. While evidence demonstrates strong connections between spirituality and/or religion to wellbeing outcomes, little is known about spiritual care in ambulance services or its impact. The aim of this study was to investigate paramedics' perspectives on the role and value of Australian ambulance chaplains. A cross-sectional online study of registered paramedics in Australia was conducted between November and December 2022. Analysis of the 150 responses identified that paramedics viewed the chaplain's role as one built on professional caring relationships that provided proactive and reactive care in paramedic workplaces. Chaplains were perceived to promote wellbeing by incorporating emotional, psychological, social and spiritual care, and assisting paramedics to access additional support. Perceived religiousness of chaplains and organisational factors were barriers to paramedics accessing chaplains, while pre-existing relationships and shared experiences positively influenced paramedics decision to seek chaplain support.


Asunto(s)
Ambulancias , Humanos , Estudios Transversales , Australia , Femenino , Masculino , Adulto , Persona de Mediana Edad , Ambulancias/estadística & datos numéricos , Clero/psicología , Clero/estadística & datos numéricos , Encuestas y Cuestionarios , Espiritualidad , Rol Profesional , Cuidado Pastoral , Servicios Médicos de Urgencia/estadística & datos numéricos , Técnicos Medios en Salud/psicología , Técnicos Medios en Salud/estadística & datos numéricos
17.
Am J Physiol Endocrinol Metab ; 304(10): E1097-104, 2013 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-23531616

RESUMEN

In addition to its acute effects on hormone secretion, epithelial transport, and shape change, the calcium-sensing receptor (CaSR) modulates the expression of genes that control cell survival, proliferation, and differentiation as well as the synthesis of peptide hormones and enzymes. In the present study, we investigated the impacts of a CaSR agonist and several CaSR modulators on phosphorylation of transcription factor CREB residue Ser(133) in CaSR-expressing HEK293 (HEK-CaSR) cells and human adenomatous parathyroid cells. Elevated Ca(2+)o concentration had no effect on CREB phosphorylation (p-CREB) in control HEK293 cells but stimulated p-CREB in both HEK-CaSR cells and human parathyroid cells. In addition, p-CREB was stimulated by the positive modulator cinacalcet and inhibited by the negative modulator NPS 2143 in both CaSR-expressing cell types. Two positive modulators that bind in the receptor's Venus Fly Trap domain, l-phenylalanine and S-methylglutathione, had no effect on p-CREB in HEK-CaSR cells, demonstrating the existence of pronounced signaling bias. Analysis of the signaling pathways using specific inhibitors demonstrated that phosphoinositide-specific phospholipase C and conventional protein kinase C isoforms make major contributions to Ca(2+)o-induced p-CREB in both cell-types, suggesting key roles for Gq/11. In addition, in parathyroid cells but not HEK-CaSR cells, activation of p-CREB was dependent on Gi/o, demonstrating the existence of cell type-specific signaling.


Asunto(s)
Proteína de Unión a CREB/metabolismo , Calcio/metabolismo , Glándulas Paratiroides/metabolismo , Receptores Sensibles al Calcio/metabolismo , Cinacalcet , Glutatión/análogos & derivados , Glutatión/farmacología , Células HEK293 , Humanos , Naftalenos/farmacología , Fenilalanina/farmacología , Fosforilación , Transducción de Señal
18.
Nurse Educ Today ; 131: 105957, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37734368

RESUMEN

BACKGROUND: Compassion and empathy are integral to safe and effective patient care. However, to date, most studies have focused on exploring, defining, measuring and analysing empathy and compassion from the perspective of researchers or clinicians. There has been limited attention to the perspectives of patients. OBJECTIVE: The objective of this scoping review was to map the literature to identify patients' views of healthcare provider behaviours that exemplify empathic and compassionate interactions. METHOD: This review used the Joanna Briggs Institute scoping review methodology. A comprehensive search of eight electronic databases was conducted with English language studies published in the last 10 years considered for inclusion. RESULTS: Database searching resulted in 459 records for initial screening. After de-duplication and conducting a title and abstract review, 32 full-text articles were screened for eligibility. A total of 14 studies met the inclusion criteria and were critically reviewed using the Mixed Methods Appraisal Tool. The included papers profiled studies that had been conducted in clinical settings across seven countries. The healthcare encounters described in the papers were with a range of healthcare providers. Two overarching and interconnected categories of behaviours were identified as indicative of empathic/compassionate encounters: (1) communication skills such as listening, touch, body language, eye contact and positive demeanour; and (2) helping behaviours demonstrated by small acts of kindness that go beyond routine healthcare. CONCLUSION: Given the breadth of studies describing the positive impact of empathy/compassion on people's physical and psychosocial wellbeing, the results from this review are valuable and shed new light on patients' views and experiences. The results provide a deeper understanding of healthcare provider behaviours that exemplify empathic and compassionate healthcare interactions and can be used to inform the education and training of healthcare providers from all disciplines.


Asunto(s)
Atención a la Salud , Empatía , Humanos , Personal de Salud/educación , Pacientes
19.
Elife ; 122023 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-37248726

RESUMEN

Allosteric modulation of G protein-coupled receptors (GPCRs) is a major paradigm in drug discovery. Despite decades of research, a molecular-level understanding of the general principles that govern the myriad pharmacological effects exerted by GPCR allosteric modulators remains limited. The M4 muscarinic acetylcholine receptor (M4 mAChR) is a validated and clinically relevant allosteric drug target for several major psychiatric and cognitive disorders. In this study, we rigorously quantified the affinity, efficacy, and magnitude of modulation of two different positive allosteric modulators, LY2033298 (LY298) and VU0467154 (VU154), combined with the endogenous agonist acetylcholine (ACh) or the high-affinity agonist iperoxo (Ipx), at the human M4 mAChR. By determining the cryo-electron microscopy structures of the M4 mAChR, bound to a cognate Gi1 protein and in complex with ACh, Ipx, LY298-Ipx, and VU154-Ipx, and applying molecular dynamics simulations, we determine key molecular mechanisms underlying allosteric pharmacology. In addition to delineating the contribution of spatially distinct binding sites on observed pharmacology, our findings also revealed a vital role for orthosteric and allosteric ligand-receptor-transducer complex stability, mediated by conformational dynamics between these sites, in the ultimate determination of affinity, efficacy, cooperativity, probe dependence, and species variability. There results provide a holistic framework for further GPCR mechanistic studies and can aid in the discovery and design of future allosteric drugs.


Asunto(s)
Receptor Muscarínico M4 , Receptores Muscarínicos , Humanos , Acetilcolina/metabolismo , Regulación Alostérica , Sitio Alostérico , Microscopía por Crioelectrón , Ligandos , Receptor Muscarínico M4/agonistas , Receptor Muscarínico M4/metabolismo
20.
Handb Exp Pharmacol ; (208): 29-48, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22222693

RESUMEN

There has been great interest in the structure-function relationships of the muscarinic acetylcholine receptors (mAChRs) because these prototypical Family A/class 1 G protein-coupled receptors (GPCRs) are attractive therapeutic targets for both peripheral and central nervous system disorders. A multitude of drugs that act at the mAChRs have been identified over the years, but many of these show minimal selectivity for any one of the five mAChR subtypes over the others, which has hampered their development into therapeutics due to adverse side effects. The lack of drug specificity is primarily due to high sequence similarity in this family of receptor, especially in the orthosteric binding pocket. Thus, there remains an ongoing need for a molecular understanding of how mAChRs bind their ligands, and how selectivity in binding and activation can be achieved. Unfortunately, there remains a paucity of solved high-resolution structures of GPCRs, including the mAChRs, and thus most of our knowledge of structure-function mechanisms related to this receptor family to date has been obtained indirectly through approaches such as mutagenesis. Nonetheless, such studies have revealed a wealth of information that has led to novel insights and may be used to guide future rational drug design campaigns.


Asunto(s)
Acetilcolina/metabolismo , Receptores Muscarínicos/metabolismo , Transducción de Señal , Secuencia de Aminoácidos , Animales , Sitios de Unión , Humanos , Ligandos , Modelos Moleculares , Datos de Secuencia Molecular , Mutación , Conformación Proteica , Receptores Muscarínicos/química , Receptores Muscarínicos/clasificación , Receptores Muscarínicos/efectos de los fármacos , Receptores Muscarínicos/genética , Transducción de Señal/efectos de los fármacos , Relación Estructura-Actividad
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