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1.
J Anat ; 243(4): 697-705, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37222261

RESUMEN

The aim of this study is to correlate small dot hyper-reflective foci (HRF) observed in spectral domain optical coherence tomography (SD-OCT) scans of an animal model of hyperglycaemia with focal electroretinography (fERG) response and immunolabelling of retinal markers. The eyes of an animal model of hyperglycaemia showing signs of diabetic retinopathy (DR) were imaged using SD-OCT. Areas showing dot HRF were further evaluated using fERG. Retinal areas enclosing the HRF were dissected and serially sectioned, stained and labelled for glial fibrillary acidic protein (GFAP) and a microglial marker (Iba-1). Small dot HRF were frequently seen in OCT scans in all retinal quadrants in the inner nuclear layer or outer nuclear layer in the DR rat model. Retinal function in the HRF and adjacent areas was reduced compared with normal control rats. Microglial activation was detected by Iba-1 labelling and retinal stress identified by GFAP expression in Müller cells observed in discrete areas around small dot HRF. Small dot HRF seen in OCT images of the retina are associated with a local microglial response. This study provides the first evidence of dot HRF correlating with microglial activation, which may allow clinicians to better evaluate the microglia-mediated inflammatory component of progressive diseases showing HRF.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Hiperglucemia , Ratas , Animales , Retinopatía Diabética/diagnóstico por imagen , Tomografía de Coherencia Óptica , Retina/diagnóstico por imagen , Inflamación/diagnóstico por imagen
2.
Alzheimers Dement ; 19(5): 1800-1820, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36284403

RESUMEN

INTRODUCTION: The credibility of model-based economic evaluations of Alzheimer's disease (AD) interventions is central to appropriate decision-making in a policy context. We report on the International PharmacoEconomic Collaboration on Alzheimer's Disease (IPECAD) Modeling Workshop Challenge. METHODS: Two common benchmark scenarios, for the hypothetical treatment of AD mild cognitive impairment (MCI) and mild dementia, were developed jointly by 29 participants. Model outcomes were summarized, and cross-comparisons were discussed during a structured workshop. RESULTS: A broad concordance was established among participants. Mean 10-year restricted survival and time in MCI in the control group ranged across 10 MCI models from 6.7 to 9.5 years and 3.4 to 5.6 years, respectively; and across 4 mild dementia models from 5.4 to 7.9 years (survival) and 1.5 to 4.2 years (mild dementia). DISCUSSION: The model comparison increased our understanding of methods, data used, and disease progression. We established a collaboration framework to assess cost-effectiveness outcomes, an important step toward transparent and credible AD models.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Demencia , Humanos , Enfermedad de Alzheimer/terapia , Análisis Costo-Beneficio , Economía Farmacéutica , Progresión de la Enfermedad
3.
Int J Mol Sci ; 24(4)2023 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-36835288

RESUMEN

Diabetic retinopathy (DR), a microvascular complication of diabetes, is associated with pronounced inflammation arising from the activation of a nucleotide-binding and oligomerization domain-like receptor (NLR) protein 3 (NLRP3) inflammasome. Cell culture models have shown that a connexin43 hemichannel blocker can prevent inflammasome activation in DR. The aim of this study was to evaluate the ocular safety and efficacy of tonabersat, an orally bioavailable connexin43 hemichannel blocker, to protect against DR signs in an inflammatory non-obese diabetic (NOD) DR mouse model. For retina safety studies, tonabersat was applied to retinal pigment epithelial (ARPE-19) cells or given orally to control NOD mice in the absence of any other stimuli. For efficacy studies, either tonabersat or a vehicle was given orally to the inflammatory NOD mouse model two hours before an intravitreal injection of pro-inflammatory cytokines, interleukin-1 beta, and tumour necrosis factor-alpha. Fundus and optical coherence tomography images were acquired at the baseline as well as at 2- and 7-day timepoints to assess microvascular abnormalities and sub-retinal fluid accumulation. Retinal inflammation and inflammasome activation were also assessed using immunohistochemistry. Tonabersat did not have any effect on ARPE-19 cells or control NOD mouse retinas in the absence of other stimuli. However, the tonabersat treatment in the inflammatory NOD mice significantly reduced macrovascular abnormalities, hyperreflective foci, sub-retinal fluid accumulation, vascular leak, inflammation, and inflammasome activation. These findings suggest that tonabersat may be a safe and effective treatment for DR.


Asunto(s)
Benzamidas , Conexina 43 , Retinopatía Diabética , Animales , Ratones , Conexina 43/antagonistas & inhibidores , Retinopatía Diabética/tratamiento farmacológico , Modelos Animales de Enfermedad , Inflamasomas/metabolismo , Inflamación/metabolismo , Ratones Endogámicos NOD , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Administración Oral , Benzamidas/administración & dosificación , Benzamidas/farmacología
4.
Int J Mol Sci ; 24(24)2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-38139284

RESUMEN

Multiple sclerosis (MS) is a neurodegenerative disease marked by chronic neuroinflammation thought to be mediated by the inflammasome pathway. Connexin 43 (Cx43) hemichannels contribute to the activation of the inflammasome through the release of adenosine triphosphate (ATP) inflammasome activation signals. The objective of the study was to evaluate if the Cx43 hemichannel blocker, tonabersat, is effective in modulating the inflammatory response and reducing disability in the myelin oligodendrocyte glycoprotein 35-55-induced experimental autoimmune encephalomyelitis (MOG35-55 EAE) model of MS. Here, we show that the Cx43 hemichannel blocking drug, tonabersat, significantly reduced expression of neuroinflammatory markers for microglial activation (ionized calcium-binding adapter molecule 1 (Iba1)) and astrogliosis (glial fibrillary acidic protein (GFAP)) while preserving myelin basic protein (MBP) expression levels in the corpus callosum, motor cortex, and striatum regions of the brain in MOG35-55 EAE mice. Reduced NOD-like receptor protein 3 (NLRP3) inflammasome complex assembly and Caspase-1 activation confirmed the drug's mode of action. MOG35-55 EAE mice showed clinical signs of MS, but MOG35-55 EAE mice treated with tonabersat retained behavior closer to normal. These data suggest that clinical trial phase IIb-ready tonabersat may merit further investigation as a promising candidate for MS treatment.


Asunto(s)
Encefalomielitis Autoinmune Experimental , Esclerosis Múltiple , Enfermedades Neurodegenerativas , Ratones , Animales , Esclerosis Múltiple/tratamiento farmacológico , Conexina 43/metabolismo , Inflamasomas/metabolismo , Progresión de la Enfermedad , Ratones Endogámicos C57BL , Modelos Animales de Enfermedad
5.
Exp Eye Res ; 215: 108911, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34958779

RESUMEN

The inflammasome pathway is a fundamental component of the innate immune system, playing a key role especially in chronic age-related eye diseases (AREDs). The inflammasome is of particular interest because it is a common disease pathway that once instigated, can amplify and perpetuate itself leading to chronic inflammation. With aging, it becomes more difficult to shut down inflammation after an insult but the common pathway means that a shared solution may be feasible that could be effective across multiple disease indications. This review focusses on the NLRP3 inflammasome, the most studied and characterized inflammasome in the eye. It describes the two-step signalling required for NLRP3 inflammasome complex activation, and provides evidence for its role in AREDs. In the final section, the article gives an overview of potential NLRP3 inflammasome targeting therapies, before presenting evidence for connexin hemichannel regulators as upstream blockers of inflammasome activation. These have shown therapeutic efficacy in multiple ocular disease models.


Asunto(s)
Oftalmopatías , Inflamasomas , Animales , Enfermedad Crónica , Conexinas , Humanos , Inflamasomas/metabolismo , Inflamación/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo
6.
Mult Scler ; 28(3): 346-351, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32880511

RESUMEN

BACKGROUND: It is a familiar story. A promising multiple sclerosis (MS) treatment clears the three regulatory hurdles of safety, quality and efficacy, only to fall at the fourth: cost-effectiveness. This has led to concerns about the validity of the measures typically used to quantify treatment effects in cost-effectiveness analyses and in 2012, in the United Kingdom, the National Institute for Health and Care Excellence called for an improvement in the cost-effectiveness framework for assessing MS treatments. OBJECTIVE AND METHODS: This review describes what is meant by cost-effectiveness in health/social care funding decision-making, and usual practice for assessing treatment benefits. RESULTS: We detail the use of the quality-adjusted life-year (QALY) in resource allocation decisions, and set out limitations of this approach in the context of MS. CONCLUSION: We conclude by highlighting methodological and policy developments which should aid addressing these limitations.


Asunto(s)
Esclerosis Múltiple , Análisis Costo-Beneficio , Humanos , Esclerosis Múltiple/terapia , Años de Vida Ajustados por Calidad de Vida , Reino Unido
7.
Cell Biol Int ; 46(2): 323-330, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34719065

RESUMEN

Epithelial-mesenchymal transition (EMT) occurs when polarised epithelial cells change to a mesenchymal phenotype. EMT plays a role in several chronic conditions, including ocular diseases with retinal pigment epithelium (RPE) EMT associated with retinal diseases such as diabetic retinopathy (DR). Here, EMT results in breakdown of the blood-retinal barrier (BRB) leading to sub-retinal fluid deposition and retinal detachment. Previous studies have shown that blocking connexin43 (Cx43) hemichannels can protect against RPE BRB breakdown, but the underlying mechanism is unknown. To determine whether open Cx43 hemichannels may enable EMT of RPE cells and thus result in BRB breakdown, ARPE-19 cells were either challenged with high glucose plus the inflammatory cytokines IL-1ß and TNF-α (HG + Cyt) to simulate DR or treated with the Cx43 hemichannel blocker tonabersat alongside the HG + Cyt challenge. HG + Cyt induced a morphological change in RPE cells to a fibroblastic phenotype with a corresponding decrease in epithelial zonular occludens-1 and an increase in the fibroblastic marker α-SMA. The HG + Cyt challenge also induced loss of transepithelial electrical resistance while increasing dye passage between RPE cells. All of these changes were significantly reduced with tonabersat treatment, which also prevented HG + Cyt-induced transforming growth factor-ß2 (TGF-ß2) release. In conclusion, Cx43 hemichannel block with tonabersat attenuated both TGF-ß2 release and RPE EMT under disease-mimicking conditions, offering the potential to ameliorate the progression of EMT-associated retinal diseases.


Asunto(s)
Transición Epitelial-Mesenquimal , Factor de Crecimiento Transformador beta2 , Conexina 43/metabolismo , Células Epiteliales/metabolismo , Humanos , Epitelio Pigmentado de la Retina/metabolismo , Factor de Crecimiento Transformador beta2/metabolismo , Factor de Crecimiento Transformador beta2/farmacología , Regulación hacia Arriba
8.
Value Health ; 25(8): 1399-1403, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35393254

RESUMEN

There is strong evidence that individuals and the public assign relatively greater value to health gains from relatively more severe health states. This preference is increasingly reflected in health technology assessment, with some consideration of severity incorporated by health technology assessment bodies in, among others, The Netherlands, England and Wales, Norway, Sweden, and the United States. If a societal "severity premium" is to be considered fairly and consistently, we argue that a more explicit and quantitative approach is needed. We highlight drawbacks of categorical approaches, especially discontinuities between severity categories that arguably violate concepts of vertical equity, and argue that a more continuous approach to understanding severity is needed. We also note challenges to more explicit approaches, including implications of a lower threshold for less severe conditions and the relative complexity of calculating a continuous severity adjustment.


Asunto(s)
Tecnología Biomédica , Evaluación de la Tecnología Biomédica , Inglaterra , Humanos , Noruega , Estados Unidos , Gales
9.
Health Econ ; 31(8): 1752-1769, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35648106

RESUMEN

Driving under the influence of alcohol is a major cause of fatalities worldwide. There have been a range of legislative and policy interventions aiming to address this. Bar closing hours is one policy with clear implications for drink driving. Existing evidence, largely drawn from one-off policy changes in urban settings, reports mixed evidence that is difficult to generalize. We return to this issue using a setting, Norway, that is advantageous due to large temporal and regional variation in closing times, frequent changes, and a lack of confounding policy changes. We demonstrate an average zero effect of closing hours on traffic accidents that masks large variations in effects: in terms of population density; accident severity; and direction of change in closing hours. Extensions in closing hours in populous municipalities decrease accidents, whereas the opposite is true for rural municipalities. Our findings suggest that estimates from single policy changes may be difficult to generalize, while demonstrating that closing hours can generate large effects on traffic accidents.


Asunto(s)
Accidentes de Tránsito , Conducción de Automóvil , Ciudades , Humanos , Noruega/epidemiología , Población Rural
10.
Exp Cell Res ; 407(2): 112823, 2021 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-34506760

RESUMEN

Cell transdifferentiation is the conversion of a cell type to another without requiring passage through a pluripotent cell state, and encompasses epithelial- and endothelial-mesenchymal transition (EMT and EndMT). EMT and EndMT are well defined processes characterized by a loss of epithelial/endothelial phenotype and gain in mesenchymal spindle shaped morphology, which results in increased cell migration and decreased apoptosis and cellular senescence. Such cells often develop invasive properties. Physiologically, these processes may occur during embryonic development and can resurface, for example, to promote wound healing in later life. However, they can also be a pathological process. In the eye, EMT, EndMT and cell transdifferentiation have all been implicated in development, homeostasis, and multiple diseases affecting different parts of the eye. Connexins, constituents of connexin hemichannels and intercellular gap junctions, have been implicated in many of these processes. In this review, we firstly provide an overview of the molecular mechanisms induced by transdifferentiation (including EMT and EndMT) and its involvement in eye diseases. We then review the literature for the role of connexins in transdifferentiation in the eye and eye diseases. The evidence presented in this review supports the need for more studies into the therapeutic potential for connexin modulators in prevention and treatment of transdifferentiation related eye diseases, but does indicate that connexin channel modulation may be an upstream and unifying approach for regulating these otherwise complex processes.


Asunto(s)
Transdiferenciación Celular , Conexinas/metabolismo , Transición Epitelial-Mesenquimal , Oftalmopatías/patología , Factor de Crecimiento Transformador beta/metabolismo , Animales , Oftalmopatías/metabolismo , Humanos , Transducción de Señal
11.
Age Ageing ; 51(9)2022 09 02.
Artículo en Inglés | MEDLINE | ID: mdl-36057987

RESUMEN

Approximately two-thirds of hospital admissions are older adults and almost half of these are likely to have some form of dementia. People with dementia are not only at an increased risk of adverse outcomes once admitted, but the unfamiliar environment and routinised practices of the wards and acute care can be particularly challenging for them, heightening their confusion, agitation and distress further impacting the ability to optimise their care. It is well established that a person-centred care approach helps alleviate some of the unfamiliar stress but how to embed this in the acute-care setting remains a challenge. In this article, we highlight the challenges that have been recognised in this area and put forward a set of evidence-based 'pointers for service change' to help organisations in the delivery of person-centred care. The DEMENTIA CARE pointers cover areas of: dementia awareness and understanding, education and training, modelling of person-centred care by clinical leaders, adapting the environment, teamwork (not being alone), taking the time to 'get to know', information sharing, access to necessary resources, communication, involving family (ask family), raising the profile of dementia care, and engaging volunteers. The pointers extend previous guidance, by recognising the importance of ward cultures that prioritise dementia care and institutional support that actively seeks to raise the profile of dementia care. The pointers provide a range of simple to more complex actions or areas for hospitals to help implement person-centred care approaches; however, embedding them within the organisational cultures of hospitals is the next challenge.


Asunto(s)
Demencia , Anciano , Comunicación , Demencia/diagnóstico , Demencia/terapia , Hospitales , Humanos , Atención Dirigida al Paciente
12.
J Cell Physiol ; 236(2): 911-920, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32592185

RESUMEN

Connexin31.1 (Cx31.1) is a gap junction protein associated with apoptosis. In the skin, apoptosis is modulated by diabetes. A HaCaT skin model investigated whether normal (NGI) and high glucose and insulin (HGI; diabetic) conditions altered Cx31.1 expression, and if these were apoptosis linked. Cx31.1 was found in HaCaT and HeLa Ohio cells, with HaCaT Cx31.1 protein increased in HGI conditions, and around apoptotic cells. HeLa Cx31.1 channels were noncommunicative. Post scrape-wounding, Cx31.1 increased at wound edges. Caspase 3/7 in scrape-wounds media (containing cells) elevated in HGI. UV exposure raised Cx31.1, and caspase 3/7, in NGI and HGI. UV reduced cell viability in NGI cells, although not significantly in HGI. Cx31.1 is modulated during HaCaT cell wound closure, and associated with 'diabetic' conditions. Cx31.1 expression matched apoptosis levels, higher in HGI cultures. Cx31.1 is noncommunicating, modulated after wounding, linked to apoptosis, and may be associated with tissue turn-over around diabetic wounds.


Asunto(s)
Conexinas/metabolismo , Heridas y Lesiones/metabolismo , Apoptosis/fisiología , Línea Celular , Línea Celular Tumoral , Supervivencia Celular/fisiología , Células HaCaT , Células HeLa , Humanos , Insulina/metabolismo
13.
Exp Eye Res ; 202: 108384, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33285185

RESUMEN

Diabetic retinopathy (DR), the most common ocular complication associated with diabetes, is a chronic vascular and inflammatory disease that leads to vision loss. The inflammasome pathway, a key part of the innate immune system, is required to activate chronic inflammation in DR. Unfortunately, current therapies for DR target pathological signs that are downstream of the inflammasome pathway, making them only partly effective in treating the disease. Using in vitro and in vivo DR models, it was discovered that connexin43 hemichannel blockers can inhibit activation of the inflammasome pathway. However, those studies were conducted using in vitro cell culture and in vivo animal disease models that are predictive but do not, of course, like any model, completely replicate the human condition. Here, we have developed an addition to our armamentarium of useful models, an ex vivo human organotypic retinal culture model of DR by exposing human donor retinal explants to a combination of high glucose (HG) and pro-inflammatory cytokines, interleukin-1 beta (IL-1ß) and tumour necrosis factor alpha (TNF-α). We hypothesized that in this model, connexin43 hemichannel block would protect against NLRP3 inflammasome complex assembly which would in turn decrease signs of inflammation characteristic of DR. To test our hypothesis, molecular changes in the inflammatory and inflammasome pathway were assessed using immunohistochemistry and a Luminex cytokine release assay. Our results showed that the human retinal explant DR model was associated with increased inflammation and activation of the inflammasome pathway, characteristic of the human condition. Furthermore, we showed that by blocking connexin43 hemichannels with the hemichannel modulator, tonabersat, we were able to prevent NLRP3 inflammasome complex assembly, Müller cell activation, as well as release of pro-inflammatory cytokines and VEGF. This further supports the possible use of connexin43 hemichannel blockers as potential new therapies for DR.


Asunto(s)
Benzamidas/farmacología , Benzopiranos/farmacología , Conexina 43/metabolismo , Retinopatía Diabética/tratamiento farmacológico , Inflamasomas/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Anciano , Anciano de 80 o más Años , Retinopatía Diabética/metabolismo , Retinopatía Diabética/patología , Femenino , Humanos , Microscopía Confocal , Persona de Mediana Edad
14.
J Occup Rehabil ; 31(3): 613-626, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33502661

RESUMEN

Purpose Research indicates that employment is beneficial for people with multiple sclerosis (MS). However, people with MS typically face reduced workforce participation compared to the general population. Using a discrete choice experiment (DCE) we explored which factors are most important in influencing employment choices of people with MS, and whether the relative importance of factors differs between subgroups. Methods Attributes and levels for the DCE were developed using a systematic literature review and public involvement techniques with people with MS. In an online survey, respondents were asked to choose between two hypothetical job scenarios described using six attributes. We used a large, national register (the UK MS Register), to recruit participants aged 18-64 years with a diagnosis of MS. Choice data were analysed using multinomial logit and latent class models. Results Analyses were based on responses from 2350 people with MS. The preferred model specification was a latent class model, with three classes of respondent. The relative importance of attributes varied between classes, with one giving the greatest weight to the impact of work on other aspects of their lives, the second to having supportive bosses and colleagues, and the third to job flexibility. The classes differed significantly in terms of age and gender, type of MS, and socio-economic status. Conclusions Significant heterogeneity was apparent among people with MS regarding the factors that influence their employment decisions. Attributes concerning the impact of work, attitudes in the workplace and job flexibility appear more influential than those concerning physical workplace adaptations.


Asunto(s)
Esclerosis Múltiple , Empleo , Humanos , Recursos Humanos , Lugar de Trabajo
15.
Neuromodulation ; 24(6): 1033-1041, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33905144

RESUMEN

OBJECTIVES: To undertake a detailed healthcare resource use and cost analysis of the SubQStim study, which randomized patients with failed back surgery syndrome (FBSS) with low back pain to receive subcutaneous nerve field stimulation in combination with optimized medical management (treatment) or optimized medical management alone (control). MATERIALS AND METHODS: Patient-level data from the SubQStim study were used to present descriptive analyses of healthcare resource use and estimated costs for pain medication, healthcare visits, adverse events, and device acquisition/implantation. A United Kingdom National Health Service perspective was adopted, using cost data from national tariffs, drug and device prices, and social care cost studies. Results were calculated as the mean cost per patient over the nine-month follow-up period. RESULTS: Mean cost per patient was £18,403 in the treatment group versus £1613 in the control group. Almost 90% of the cost in the treatment group consisted of device acquisition/implantation. Higher adverse event costs were observed for patients in the treatment group, but lower costs were observed for pain medication and healthcare visits. Over nine months, opioid use decreased in the treatment group and increased in the control group. Enrolment and follow-up were terminated early in the clinical study, leading to substantial between-patient variability in each cost category. CONCLUSIONS: Subcutaneous nerve field stimulation has the potential to offset the initial costs of the device by reducing analgesic medication and the number of healthcare visits in FBSS patients, alongside potential gains in health-related quality of life. There remains uncertainty in long-term costs and cost-effectiveness of stimulation and longer-term follow-up analyses are needed.


Asunto(s)
Síndrome de Fracaso de la Cirugía Espinal Lumbar , Dolor de la Región Lumbar , Análisis Costo-Beneficio , Síndrome de Fracaso de la Cirugía Espinal Lumbar/terapia , Humanos , Dimensión del Dolor , Calidad de Vida , Medicina Estatal
16.
Int J Mol Sci ; 22(4)2021 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-33578721

RESUMEN

Dysregulation of retinal function in the early stages of light-induced retinal degeneration involves pannexins and connexins. These two types of proteins may contribute to channels that release ATP, leading to activation of the inflammasome pathway, spread of inflammation and retinal dysfunction. However, the effect of pannexin channel block alone or block of both pannexin channels and connexin hemichannels in parallel on retinal activity in vivo is unknown. In this study, the pannexin channel blocker probenecid and the connexin hemichannel blocker tonabersat were used in the light-damaged rat retina. Retinal function was evaluated using electroretinography (ERG), retinal structure was analyzed using optical coherence tomography (OCT) imaging and the tissue response to light-induced injury was assessed immunohistochemically with antibodies against glial fibrillary acidic protein (GFAP), Ionized calcium binding adaptor molecule 1 (Iba-1) and Connexin43 (Cx43). Probenecid did not further enhance the therapeutic effect of connexin hemichannel block in this model, but on its own improved activity of certain inner retina neurons. The therapeutic benefit of blocking connexin hemichannels was further evaluated by comparing these data against results from our previously published studies that also used the light-damaged rat retina model. The analysis showed that treatment with tonabersat alone was better than probenecid alone at restoring retinal function in the light-damaged retina model. The results assist in the interpretation of the differential action of connexin hemichannel and pannexin channel therapeutics for potential treatment of retinal diseases.


Asunto(s)
Benzamidas/uso terapéutico , Benzopiranos/uso terapéutico , Conexinas/antagonistas & inhibidores , Proteínas del Tejido Nervioso/antagonistas & inhibidores , Probenecid/uso terapéutico , Retina/efectos de los fármacos , Enfermedades de la Retina/tratamiento farmacológico , Animales , Benzamidas/farmacología , Benzopiranos/farmacología , Conexina 43/análisis , Femenino , Inflamación/tratamiento farmacológico , Inflamación/etiología , Inflamación/patología , Luz/efectos adversos , Masculino , Probenecid/farmacología , Ratas , Ratas Sprague-Dawley , Retina/patología , Retina/efectos de la radiación , Enfermedades de la Retina/etiología , Enfermedades de la Retina/patología
17.
Int J Mol Sci ; 22(7)2021 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-33807408

RESUMEN

Chronic Kidney Disease (CKD) is associated with sustained inflammation and progressive fibrosis, changes that have been linked to altered connexin hemichannel-mediated release of adenosine triphosphate (ATP). Kidney fibrosis develops in response to increased deposition of extracellular matrix (ECM), and up-regulation of collagen I is an early marker of renal disease. With ECM remodeling known to promote a loss of epithelial stability, in the current study we used a clonal human kidney (HK2) model of proximal tubular epithelial cells to determine if collagen I modulates changes in cell function, via connexin-43 (Cx43) hemichannel ATP release. HK2 cells were cultured on collagen I and treated with the beta 1 isoform of the pro-fibrotic cytokine transforming growth factor (TGFß1) ± the Cx43 mimetic Peptide 5 and/or an anti-integrin α2ß1 neutralizing antibody. Phase microscopy and immunocytochemistry observed changes in cell morphology and cytoskeletal reorganization, whilst immunoblotting and ELISA identified changes in protein expression and secretion. Carboxyfluorescein dye uptake and biosensing measured hemichannel activity and ATP release. A Cytoselect extracellular matrix adhesion assay assessed changes in cell-substrate interactions. Collagen I and TGFß1 synergistically evoked increased hemichannel activity and ATP release. This was paralleled by changes to markers of tubular injury, partly mediated by integrin α2ß1/integrin-like kinase signaling. The co-incubation of the hemichannel blocker Peptide 5, reduced collagen I/TGFß1 induced alterations and inhibited a positive feedforward loop between Cx43/ATP release/collagen I. This study highlights a role for collagen I in regulating connexin-mediated hemichannel activity through integrin α2ß1 signaling, ahead of establishing Peptide 5 as a potential intervention.


Asunto(s)
Colágeno Tipo I/metabolismo , Conexina 43/metabolismo , Túbulos Renales Proximales/metabolismo , Adenosina Trifosfato/metabolismo , Calcio/metabolismo , Adhesión Celular , Línea Celular , Células Cultivadas , Colágeno Tipo I/fisiología , Conexina 43/fisiología , Conexinas/metabolismo , Citocinas , Células Epiteliales/metabolismo , Humanos , Integrina alfa2beta1/metabolismo , Integrina alfa2beta1/fisiología , Insuficiencia Renal Crónica/metabolismo , Insuficiencia Renal Crónica/fisiopatología , Transducción de Señal , Factor de Crecimiento Transformador beta1/metabolismo
18.
Cell Commun Signal ; 18(1): 79, 2020 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-32450899

RESUMEN

BACKGROUND: Tubulointerstitial fibrosis represents the key underlying pathology of Chronic Kidney Disease (CKD), yet treatment options remain limited. In this study, we investigated the role of connexin43 (Cx43) hemichannel-mediated adenosine triphosphate (ATP) release in purinergic-mediated disassembly of adherens and tight junction complexes in early tubular injury. METHODS: Human primary proximal tubule epithelial cells (hPTECs) and clonal tubular epithelial cells (HK2) were treated with Transforming Growth Factor Beta1 (TGF-ß1) ± apyrase, or ATPγS for 48 h. For inhibitor studies, cells were co-incubated with Cx43 mimetic Peptide 5, or purinergic receptor antagonists Suramin, A438079 or A804598. Immunoblotting, single-cell force spectroscopy and trans-epithelial electrical resistance assessed protein expression, cell-cell adhesion and paracellular permeability. Carboxyfluorescein uptake and biosensing measured hemichannel activity and real-time ATP release, whilst a heterozygous Cx43+/- mouse model with unilateral ureteral obstruction (UUO) assessed the role of Cx43 in vivo. RESULTS: Immunohistochemistry of biopsy material from patients with diabetic nephropathy confirmed increased expression of purinergic receptor P2X7. TGF-ß1 increased Cx43 mediated hemichannel activity and ATP release in hPTECs and HK2 cells. The cytokine reduced maximum unbinding forces and reduced cell-cell adhesion, which translated to increased paracellular permeability. Changes were reversed when cells were co-incubated with either Peptide 5 or P2-purinoceptor inhibitors. Cx43+/- mice did not exhibit protein changes associated with early tubular injury in a UUO model of fibrosis. CONCLUSION: Data suggest that Cx43 mediated ATP release represents an initial trigger in early tubular injury via its actions on the adherens and tight junction complex. Since Cx43 is highly expressed in nephropathy, it represents a novel target for intervention of tubulointerstitial fibrosis in CKD. Video Abstract In proximal tubular epithelial cells (PTECs), tight junction proteins, including zona occuludens-1 (ZO-1), contribute to epithelial integrity, whilst the adherens junction protein epithelial (E)-cadherin (ECAD) maintains cell-cell coupling, facilitating connexin 43 (Cx43) gap junction-mediated intercellular communication (GJIC) and the direct transfer of small molecules and ions between cells. In disease, such as diabetic nephropathy, the pro-fibrotic cytokine transforming growth factor beta1 (TGF-ß1) binds to its receptor and recruits SMAD2/3 signalling ahead of changes in gene transcription and up-regulation of Cx43-mediated hemichannels (HC). Uncoupled hemichannels permit the release of adenosine triphosphate (ATP) in to the extracellular space (↑[ATP]e), where ATP binds to the P2X7 purinoreceptor and activates the nucleotide-binding domain and leucine-rich repeat containing (NLR) protein-3 (NLRP3) inflammasome. Inflammation results in epithelial-to-mesenchymal transition (EMT), fibrosis and tubular injury. A major consequence is further loss of ECAD and reduced stickiness between cells, which can be functionally measured as a decrease in the maximum unbinding force needed to uncouple two adherent cells (Fmax). Loss of ECAD feeds forward to further lessen cell-cell coupling exacerbating the switch from GJIC to HC-mediated release of ATP. Reduction in ZO-1 impedes tight junction effectiveness and decreases trans-epithelial resistance (↓TER), resulting in increased paracellular permeability.


Asunto(s)
Adenosina Trifosfato/metabolismo , Conexina 43/fisiología , Túbulos Renales , Insuficiencia Renal Crónica/metabolismo , Animales , Adhesión Celular , Línea Celular , Humanos , Túbulos Renales/metabolismo , Túbulos Renales/patología , Ratones , Persona de Mediana Edad
19.
Value Health ; 23(2): 242-250, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-32113630

RESUMEN

BACKGROUND: A major debate in the quality-adjusted life-year (QALY) literature concerns whose preferences should be used to estimate health state values (HSVs) and to calculate QALYs. OBJECTIVES: This study explores differences between public and patient values for multiple sclerosis (MS) health states, described using an MS-specific classification system (Multiple Sclerosis Impact Scale-8 Dimensions [MSIS-8D]). METHODS: The MSIS-8D is an existing preference-based measure of health-related quality of life in MS, which has 2 tariffs of HSVs, based on the preferences of a representative sample of the UK general population (n = 1702) and of people with MS living in the United Kingdom (n = 1635), elicited using the time trade-off technique. Here, we explore differences between HSVs by sample type, using descriptive statistics and multivariate regression methods. RESULTS: Overall, the survey of people with MS produced significantly higher HSVs; estimated values ranged from 0.079 to 0.883 for the general population survey and from 0.138 to 0.894 for the MS survey. Differences in HSVs were more pronounced for severe health states. The difference between patient and public values varied across the dimensions of the MSIS-8D. People with MS placed greater importance on cognition than the general population, leading to lower HSVs when impairment was at a worse level; the reverse was true for the daily activities, fatigue, and depression dimensions. CONCLUSIONS: We identified significant differences in HSVs by sample type. Using patient rather than public values may influence the results of economic evaluations, depending on the dimensions of health-related quality of life affected by the intervention being assessed, and may therefore have important consequences for reimbursement decisions.


Asunto(s)
Indicadores de Salud , Estado de Salud , Esclerosis Múltiple/diagnóstico , Prioridad del Paciente , Opinión Pública , Calidad de Vida , Años de Vida Ajustados por Calidad de Vida , Actividades Cotidianas , Adolescente , Adulto , Anciano , Estudios de Casos y Controles , Costo de Enfermedad , Femenino , Humanos , Masculino , Salud Mental , Persona de Mediana Edad , Esclerosis Múltiple/fisiopatología , Esclerosis Múltiple/psicología , Índice de Severidad de la Enfermedad , Factores de Tiempo , Reino Unido , Adulto Joven
20.
BMC Geriatr ; 20(1): 131, 2020 04 10.
Artículo en Inglés | MEDLINE | ID: mdl-32272890

RESUMEN

BACKGROUND: An increasingly high number of patients admitted to hospital have dementia. Hospital environments can be particularly confusing and challenging for people living with dementia (Plwd) impacting their wellbeing and the ability to optimize their care. Improving the experience of care in hospital has been recognized as a priority, and non-pharmacological interventions including activity interventions have been associated with improved wellbeing and behavioral outcomes for Plwd in other settings. This systematic review aimed at evaluating the effectiveness of activity interventions to improve experience of care for Plwd in hospital. METHODS: Systematic searches were conducted in 16 electronic databases up to October 2019. Reference lists of included studies and forward citation searching were also conducted. Quantitative studies reporting comparative data for activity interventions delivered to Plwd aiming to improve their experience of care in hospital were included. Screening for inclusion, data extraction and quality appraisal were performed independently by two reviewers with discrepancies resolved by discussion with a third where necessary. Standardized mean differences (SMDs) were calculated where possible to support narrative statements and aid interpretation. RESULTS: Six studies met the inclusion criteria (one randomized and five non-randomized uncontrolled studies) including 216 Plwd. Activity interventions evaluated music, art, social, psychotherapeutic, and combinations of tailored activities in relation to wellbeing outcomes. Although studies were generally underpowered, findings indicated beneficial effects of activity interventions with improved mood and engagement of Plwd while in hospital, and reduced levels of responsive behaviors. Calculated SMDs ranged from very small to large but were mostly statistically non-significant. CONCLUSIONS: The small number of identified studies indicate that activity-based interventions implemented in hospitals may be effective in improving aspects of the care experience for Plwd. Larger well-conducted studies are needed to fully evaluate the potential of this type of non-pharmacological intervention to improve experience of care in hospital settings, and whether any benefits extend to staff wellbeing and the wider ward environment.


Asunto(s)
Demencia/terapia , Calidad de la Atención de Salud , Calidad de Vida , Anciano , Anciano de 80 o más Años , Demencia/diagnóstico , Femenino , Hospitalización , Humanos , Masculino , Estudios Prospectivos , Medicina Estatal
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