The interferon-rich skin environment regulates Langerhans cell ADAM17 to promote photosensitivity in lupus.

The autoimmune disease lupus erythematosus (lupus) is characterized by photosensitivity, where even ambient ultraviolet radiation (UVR) exposure can lead to development of inflammatory skin lesions. We have previously shown that Langerhans cells (LCs) limit keratinocyte apoptosis and photosensitivity via a disintegrin and metalloprotease 17 (ADAM17)-mediated release of epidermal growth factor receptor (EGFR) ligands and that LC ADAM17 sheddase activity is reduced in lupus. Here, we sought to understand how the lupus skin environment contributes to LC ADAM17 dysfunction and, in the process, differentiate between effects on LC ADAM17 sheddase function, LC ADAM17 expression, and LC numbers. We show through transcriptomic analysis a shared IFN-rich environment in non-lesional skin across human lupus and three murine models: MRL/lpr, B6.Sle1yaa, and imiquimod (IMQ) mice. IFN-I inhibits LC ADAM17 sheddase activity in murine and human LCs, and IFNAR blockade in lupus model mice restores LC ADAM17 sheddase activity, all without consistent effects on LC ADAM17 protein expression or LC numbers. Anti-IFNAR-mediated LC ADAM17 sheddase function restoration is associated with reduced photosensitive responses that are dependent on EGFR signaling and LC ADAM17. Reactive oxygen species (ROS) is a known mediator of ADAM17 activity; we show that UVR-induced LC ROS production is reduced in lupus model mice, restored by anti-IFNAR, and is cytoplasmic in origin. Our findings suggest that IFN-I promotes photosensitivity at least in part by inhibiting UVR-induced LC ADAM17 sheddase function and raise the possibility that anifrolumab ameliorates lupus skin disease in part by restoring this function. This work provides insight into IFN-I-mediated disease mechanisms, LC regulation, and a potential mechanism of action for anifrolumab in lupus.

Palliative care to support the needs of adults with neurological disease.

Neurological diseases cause physical, psychosocial, and spiritual or existential suffering from the time of their diagnosis. Palliative care focuses on improving quality of life for people with serious illness and their families by addressing this multidimensional suffering. Evidence from clinical trials supports the ability of palliative care to improve patient and caregiver outcomes by the use of outpatient or home-based palliative care interventions for people with motor neuron disease, multiple sclerosis, or Parkinson's disease; inpatient palliative care consultations for people with advanced dementia; telephone-based case management for people with dementia in the community; and nurse-led discussions with decision aids for people with advanced dementia in long-term care. Unfortunately, most people with neurological diseases do not get the support that they need for their palliative care under current standards of healthcare. Improving this situation requires the deployment of routine screening to identify individual palliative care needs, the integration of palliative care approaches into routine neurological care, and collaboration between neurologists and palliative care specialists. Research, education, and advocacy are also needed to raise standards of care.

Methods for informing people with amyotrophic lateral sclerosis/motor neuron disease of their diagnosis.

BACKGROUND: Amyotrophic lateral sclerosis (ALS), also known as motor neuron disease (MND), causes increasing physical impairment and disability. People with ALS/MND face huge physical challenges, and the diagnosis can be a source of great psychological distress for both people with ALS/MND and their carers. In such a context, how news of the diagnosis is broken is important. At present, there are no systematic reviews of methods for informing people with ALS/MND of their diagnosis. OBJECTIVES: To examine the effects and effectiveness of different methods for informing people of a diagnosis of amyotrophic lateral sclerosis/motor neuron disease (ALS/MND), including effects on the person's knowledge and understanding of their disease, its treatment, and care; and on coping and adjustment to the effects of ALS/MND, its treatment, and care. SEARCH METHODS: We searched the Neuromuscular Specialised Register, CENTRAL, MEDLINE, Embase, PsycINFO, and two trials registers (February 2022). We contacted individuals or organisations to locate studies. We contacted study authors to obtain additional unpublished data. SELECTION CRITERIA: We planned to include randomised controlled trials (RCTs) and quasi-RCTs of techniques for informing people with ALS/MND of their diagnosis. We planned to include adults (aged 17 years or over) with ALS/MND, according to the El Escorial criteria. DATA COLLECTION AND ANALYSIS: Three review authors independently reviewed the results of the search to identify RCTs, and three review authors identified non-randomised studies to include in the discussion section. We planned that two review authors would independently extract data, and three would assess the risk of bias in any included trials. MAIN RESULTS: We did not identify any RCTs that met our inclusion criteria. AUTHORS' CONCLUSIONS: There are no RCTs that evaluate different communication strategies for breaking the bad news for people diagnosed with ALS/MND. Focused research studies are needed to assess the effectiveness and efficacy of different communication methods.

Achilles Tendons Display Region-Specific Transcriptomic Signatures Associated With Distinct Mechanical Properties.

BACKGROUND: Previous studies have examined the transcriptomes and mechanical properties of whole tendons in different regions of the body. However, less is known about these characteristics within a single tendon. PURPOSE: To develop a regional transcriptomic atlas and evaluate the region-specific mechanical properties of Achilles tendons. STUDY DESIGN: Descriptive laboratory study. METHODS: Achilles tendons from 2-month-old male Sprague Dawley rats were used. Tendons were isolated and divided into proximal, middle, and distal thirds for RNA sequencing (n = 5). For mechanical testing, the Achilles muscle-tendon-calcaneus unit was mounted in a custom-designed materials testing system with the unit clamped over the musculotendinous junction (MTJ) and the calcaneus secured at 90° of dorsiflexion (n = 9). Tendons were stretched to 20 N at a constant speed of 0.0167 mm/s. Cross-sectional area, strain, stress, and Young modulus were determined in each tendon region. RESULTS: An open-access, interactive transcriptional atlas was generated that revealed distinct gene expression signatures in each tendon region. The proximal and distal regions had the largest differences in gene expression, with 2596 genes significantly differentially regulated at least 1.5-fold (q < .01). The proximal tendon displayed increased expression of genes resembling a tendon phenotype and increased expression of nerve cell markers. The distal region displayed increases in genes involved in extracellular matrix synthesis and remodeling, immune cell regulation, and a phenotype similar to cartilage and bone. There was a 3.72-fold increase in Young modulus from the proximal to middle region (P < .01) and an additional 1.34-fold increase from the middle to distal region (P = .027). CONCLUSION: Within a single tendon, there are region-specific transcriptomic signatures and mechanical properties, and there is likely a gradient in the biological and functional phenotype from the proximal origin at the MTJ to the distal insertion at the enthesis. CLINICAL RELEVANCE: These findings improve our understanding of the underlying biological heterogeneity of tendon tissue and will help inform the future targeted use of regenerative medicine and tissue engineering strategies for patients with tendon disorders.

Single-cell transcriptomic analysis identifies extensive heterogeneity in the cellular composition of mouse Achilles tendons.

Tendon is a dense connective tissue that stores and transmits forces between muscles and bones. Cellular heterogeneity is increasingly recognized as an important factor in the biological basis of tissue homeostasis and disease, yet little is known about the diversity of cell types that populate tendon. To address this, we determined the heterogeneity of cell populations within mouse Achilles tendons using single-cell RNA sequencing. In assembling a transcriptomic atlas of Achilles tendons, we identified 11 distinct types of cells, including three previously undescribed populations of tendon fibroblasts. Prior studies have indicated that pericytes, which are found in the vasculature of tendons, could serve as a potential source of progenitor cells for adult tendon fibroblasts. Using trajectory inference analysis, we provide additional support for the notion that pericytes are likely to be at least one of the progenitor cell populations for the fibroblasts that compose adult tendons. We also modeled cell-cell interactions and identified previously undescribed ligand-receptor signaling interactions involved in tendon homeostasis. Our novel and interactive tendon atlas highlights previously underappreciated heterogeneity between and within tendon cell populations. The atlas also serves as a resource to further the understanding of tendon extracellular matrix assembly and maintenance and in the design of therapies for tendinopathies.

EAN Guideline on Palliative Care of People with Severe, Progressive Multiple Sclerosis.

Background and Purpose: Patients with severe, progressive multiple sclerosis (MS) have complex physical and psychosocial needs, typically over several years. Few treatment options are available to prevent or delay further clinical worsening in this population. The objective was to develop an evidence-based clinical practice guideline for the palliative care of patients with severe, progressive MS. Methods: This guideline was developed using the Grading of Recommendations Assessment, Development and Evaluation methodology. Formulation of the clinical questions was performed in the Patients-Intervention-Comparator-Outcome format, involving patients, carers and healthcare professionals (HPs). No uniform definition of severe MS exists: in this guideline, constant bilateral support required to walk 20 m without resting (Expanded Disability Status Scale score >6.0) or higher disability is referred to. When evidence was lacking for this population, recommendations were formulated using indirect evidence or good practice statements were devised. Results: Ten clinical questions were formulated. They encompassed general and specialist palliative care, advance care planning, discussing with HPs the patient's wish to hasten death, symptom management, multidisciplinary rehabilitation, interventions for caregivers and interventions for HPs. A total of 34 recommendations (33 weak, 1 strong) and seven good practice statements were devised. Conclusions: The provision of home-based palliative care (either general or specialist) is recommended with weak strength for patients with severe, progressive MS. Further research on the integration of palliative care and MS care is needed. Areas that currently lack evidence of efficacy in this population include advance care planning, the management of symptoms such as fatigue and mood problems, and interventions for caregivers and HPs.

Widespread diversity in the transcriptomes of functionally divergent limb tendons.

KEY POINTS: Tendon is a hypocellular, matrix-rich tissue that has been excluded from comparative transcriptional atlases. These atlases have provided important knowledge about biological heterogeneity between tissues, and our study addresses this important gap. We performed measures on four of the most studied tendons, the Achilles, forepaw flexor, patellar and supraspinatus tendons of both mice and rats. These tendons are functionally distinct and are also among the most commonly injured, and therefore of important translational interest. Approximately one-third of the filtered transcriptome was differentially regulated between Achilles, forepaw flexor, patellar and supraspinatus tendons within either mice or rats. Nearly two-thirds of the transcripts that are expressed in anatomically similar tendons were different between mice and rats. The overall findings from this study identified that although tendons across the body share a common anatomical definition based on their physical location between skeletal muscle and bone, tendon is a surprisingly genetically heterogeneous tissue. ABSTRACT: Tendon is a functionally important connective tissue that transmits force between skeletal muscle and bone. Previous studies have evaluated the architectural designs and mechanical properties of different tendons throughout the body. However, less is known about the underlying transcriptional differences between tendons that may dictate their designs and properties. Therefore, our objective was to develop a comprehensive atlas of the transcriptome of limb tendons in adult mice and rats using systems biology techniques. We selected the Achilles, forepaw digit flexor, patellar, and supraspinatus tendons due to their divergent functions and high rates of injury and tendinopathies in patients. Using RNA sequencing data, we generated the Comparative Tendon Transcriptional Database (CTTDb) that identified substantial diversity in the transcriptomes of tendons both within and across species. Approximately 30% of filtered transcripts were differentially regulated between tendons of a given species, and nearly 60% of the filtered transcripts present in anatomically similar tendons were different between species. Many of the genes that differed between tendons and across species are important in tissue specification and limb morphogenesis, tendon cell biology and tenogenesis, growth factor signalling, and production and maintenance of the extracellular matrix. This study indicates that tendon is a surprisingly heterogenous tissue with substantial genetic variation based on anatomical location and species.

Prostaglandin D2 signaling is not involved in the recovery of rat hind limb tendons from injury.

Injured tendons heal through the formation of a fibrovascular scar that has inferior mechanical properties compared to native tendon tissue. Reducing inflammation that occurs as a result of the injury could limit scar formation and improve functional recovery of tendons. Prostaglandin D2 (PGD2 ) plays an important role in promoting inflammation in some injury responses and chronic disease processes, and the inhibition of PGD2 has improved healing and reduced disease burden in animal models and early clinical trials. Based on these findings, we sought to determine the role of PGD2 signaling in the healing of injured tendon tissue. We tested the hypothesis that a potent and specific inhibitor of hematopoietic PGD synthase (HPGDS), GSK2894631A, would improve the recovery of tendons of adult male rats following an acute tenotomy and repair. To test this hypothesis, we performed a full-thickness plantaris tendon tenotomy followed by immediate repair and treated rats twice daily with either 0, 2, or 6 mg/kg of GSK2894631A. Tendons were collected either 7 or 21 days after surgical repair, and mechanical properties of tendons were assessed along with RNA sequencing and histology. While there were some differences in gene expression across groups, the targeted inhibition of HPGDS did not impact the functional repair of tendons after injury, as HPGDS expression was surprisingly low in injured tendons. These results indicate that PGD2 signaling does not appear to be important in modulating the repair of injured tendon tissue.

Altering the Substrate Specificity of Acetyl-CoA Synthetase by Rational Mutagenesis of the Carboxylate Binding Pocket.

Acetyl-CoA synthetase (ACS) is a member of a large superfamily of enzymes that display diverse substrate specificities, with a common mechanism of catalyzing the formation of a thioester bond between Coenzyme A and a carboxylic acid, while hydrolyzing ATP to AMP and pyrophosphate. As an activated form of acetate, acetyl-CoA is a key metabolic intermediate that links many metabolic processes, including the TCA cycle, amino acid metabolism, fatty acid metabolism and biosynthetic processes that generate many polyketides and some terpenes. We explored the structural basis of the specificity of ACS for only activating acetate, whereas other members of this superfamily utilize a broad range of other carboxylate substrates. By computationally modeling the structure of the Arabidopsis ACS and the Pseudomonas chlororaphis isobutyryl-CoA synthetase using the experimentally determined tertiary structures of homologous ACS enzymes as templates, we identified residues that potentially comprise the carboxylate binding pocket. These predictions were systematically tested by mutagenesis of four specific residues. The resulting rationally redesigned carboxylate binding pocket modified the size and chemo-physical properties of the carboxylate binding pocket. This redesign successfully switched a highly specific enzyme from using only acetate, to be equally specific for using longer linear (up to hexanoate) or branched chain (methylvalerate) carboxylate substrates. The significance of this achievement is that it sets a precedent for understanding the structure-function relationship of an enzyme without the need for an experimentally determined tertiary structure of that target enzyme, and rationally generates new biocatalysts for metabolic engineering of a broad range of metabolic processes.

HBEGF+ macrophages in rheumatoid arthritis induce fibroblast invasiveness.

Macrophages tailor their function according to the signals found in tissue microenvironments, assuming a wide spectrum of phenotypes. A detailed understanding of macrophage phenotypes in human tissues is limited. Using single-cell RNA sequencing, we defined distinct macrophage subsets in the joints of patients with the autoimmune disease rheumatoid arthritis (RA), which affects ~1% of the population. The subset we refer to as HBEGF+ inflammatory macrophages is enriched in RA tissues and is shaped by resident fibroblasts and the cytokine tumor necrosis factor (TNF). These macrophages promoted fibroblast invasiveness in an epidermal growth factor receptor-dependent manner, indicating that intercellular cross-talk in this inflamed setting reshapes both cell types and contributes to fibroblast-mediated joint destruction. In an ex vivo synovial tissue assay, most medications used to treat RA patients targeted HBEGF+ inflammatory macrophages; however, in some cases, medication redirected them into a state that is not expected to resolve inflammation. These data highlight how advances in our understanding of chronically inflamed human tissues and the effects of medications therein can be achieved by studies on local macrophage phenotypes and intercellular interactions.

Palliative care in motor neurone disease: where are we now?

Palliative care has a very important role in the care of patients with motor neurone disease and their families. There is increasing emphasis on the multidisciplinary assessment and support of patients within guidelines, supported by research. This includes the telling of the diagnosis, the assessment and management of symptoms, consideration of interventions, such as gastrostomy and ventilatory support, and care at the end of life. The aim of palliative care is to enable patients, and their families, to maintain as good a quality of life as possible and helping to ensure a peaceful death.

Palliative care in neuromuscular diseases.

PURPOSE OF REVIEW: Palliative care is an approach that improves the quality of life of patients and their families facing the problem associated with life-threatening illness. Neuromuscular disorders (NMDs) are characterized by progressive muscle weakness, leading to pronounced and incapacitating physical disabilities. Most NMDs are not amenable to curative treatment and would thus qualify for palliative care. Amyotrophic lateral sclerosis is a relentlessly progressive disease, which leads to death about 2 years after onset due to respiratory muscle weakness. Increasingly, neurologists caring for these patients learn to apply the principles of palliative care. However, this does not yet apply to other well known and frequently occurring NMDs. RECENT FINDINGS: There is sparse literature on palliative care in NMDs such as Duchenne muscular dystrophy, spinal muscular atrophy, muscular dystrophies, some congenital myopathies, Pompe's disease and myotonic dystrophy type 1. These NMDs are often associated with imminent respiratory insufficiency and/or heart failure leading to a reduced life expectancy. Reasons for underutilization may include misconceptions about palliative care amongst patients, family carers and healthcare professionals or lack of awareness of the usefulness of this approach in these severely affected patients and the possibilities of integration of palliative principles into care for children and adults with NMDs. SUMMARY: There is an urgent need for increased attention to the development of palliative care in chronic progressive neuromuscular diseases associated with increasing functional incapacities and premature death. This will require education and training of the healthcare professionals, involvement of patient associations and funding to perform research.

Transgenerational attenuation of opioid self-administration as a consequence of adolescent morphine exposure.

The United States is in the midst of an opiate epidemic, with abuse of prescription and illegal opioids increasing steadily over the past decade. While it is clear that there is a genetic component to opioid addiction, there is a significant portion of heritability that cannot be explained by genetics alone. The current study was designed to test the hypothesis that maternal exposure to opioids prior to pregnancy alters abuse liability in subsequent generations. Female adolescent Sprague Dawley rats were administered morphine at increasing doses (5-25 mg/kg, s.c.) or saline for 10 days (P30-39). During adulthood, animals were bred with drug-naïve colony males. Male and female adult offspring (F1 animals) were tested for morphine self-administration acquisition, progressive ratio, extinction, and reinstatement at three doses of morphine (0.25, 0.75, 1.25 mg/kg/infusion). Grandoffspring (F2 animals, from the maternal line) were also examined. Additionally, gene expression changes within the nucleus accumbens were examined with RNA deep sequencing (PacBio) and qPCR. There were dose- and sex-dependent effects on all phases of the self-administration paradigm that indicate decreased morphine reinforcement and attenuated relapse-like behavior. Additionally, genes related to synaptic plasticity, as well as myelin basic protein (MBP), were dysregulated. Some, but not all, effects persisted into the subsequent (F2) generation. The results demonstrate that even limited opioid exposure during adolescence can have lasting effects across multiple generations, which has implications for mechanisms of the transmission of drug abuse liability in humans.

Palliative Care in Multiple Sclerosis.

Collaboration between the neurologist and palliative care team in the care of patients with severe demyelinating disease can result in improved patient care, and discussion of the complex ethical issues that arise when a patient expresses a wish to die may be rewarding for both patients and caregivers.

Palliative care for patients with motor neurone disease: current challenges.

Motor neurone disease is a progressive disease, and the patient and his/her family face many challenges during the disease progression, with increasing weakness and multiple losses of function. The provision of care for these patients and their families is equally challenging, anticipating and responding to the person's needs. There are increasing challenges as more is understood about the disease and its management, including the genetic basis, cognitive change, the use of interventions such as ventilatory support, and gastrostomy. There is also an increasing need to ensure that the later stages are recognized so that all can be more prepared for the end of life, including recognition of deterioration and end of life, advance care planning, symptom management and psychosocial care at the end of life, and coping with requests for assisted dying. Careful assessment and good multidisciplinary team (MDT) work can enable patients and their families to have as good a quality of life as possible, and allow a peaceful death of the patient.

Impact of disease, cognitive and behavioural factors on caregiver outcome in amyotrophic lateral sclerosis.

Up to 50% of patients with amyotrophic lateral sclerosis (ALS) show mild to moderate cognitive-behavioural change alongside their progressive functional impairment. This study examines the relative impact of patients' disease symptoms, behavioural change and current executive function and social cognition abilities on psychosocial outcomes in spouse caregivers of people with ALS. Thirty-five spouse caregivers rated their own levels of depression and anxiety, subjective burden and marital satisfaction. Caregivers also rated their partner's everyday behaviour. The patients were assessed for disease severity and cognitive function, with composite scores derived for executive function and social cognition. Regression analyses revealed that caregiver burden was predicted by the severity of patients' limb involvement and behavioural problems. Depression was predicted by patients' limb involvement, while behavioural problems and patient age predicted caregiver anxiety. Current marital satisfaction was predicted by patient behavioural problems beyond the level of pre-illness marital satisfaction. In conclusion, the study highlights the potential impact of ALS patients' functional impairment and behavioural change on ALS caregivers' psychosocial functioning. Clinical communication with ALS families should emphasise both physical and psychological challenges presented by the disease.

Executive dysfunction predicts social cognition impairment in amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder of the motor system with recognised extra-motor and cognitive involvement. This cross-sectional study examined ALS patients' performance on measures requiring social inference, and determined the relationship between such changes and variations in mood, behaviour, personality, empathy and executive function. Fifty-five ALS patients and 49 healthy controls were compared on tasks measuring social cognition and executive function. ALS patients also completed measures examining mood, behaviour and personality. Regression analyses explored the contribution of executive function, mood, behaviour and personality to social cognition scores within the ALS sample. A between-group MANOVA revealed that, the ALS group was impaired relative to controls on two composite scores for social cognition and executive function. Patients also performed worse on individual tests of executive function measuring cognitive flexibility, response inhibition and concept formation, and on individual aspects of social cognition assessing the attribution of emotional and mental states. Regression analyses indicated that ALS-related executive dysfunction was the main predictor of social cognition performance, above and beyond demographic variables, behaviour, mood and personality. On at least some aspects of social cognition, impaired performance in ALS appears to be secondary to executive dysfunction. The profile of cognitive impairment in ALS supports a cognitive continuum between ALS and frontotemporal dementia.

Healthcare professionals' views on the provision of gastrostomy and noninvasive ventilation to amyotrophic lateral sclerosis patients in England, Wales, and Northern Ireland.

Gastrostomy and noninvasive ventilation (NIV) are recommended interventions for the management of symptoms associated with amyotrophic lateral sclerosis (ALS). This study aimed to quantify the views of a range of healthcare professionals (HCPs) on the provision of these interventions in the United Kingdom. A total of 177 HCPs participated in an online survey. Significant differences were found between medical and allied HCPs' views on: whether HCPs adhere to policy and accept legal constraints when it comes to making gastrostomy available to people with ALS; the impressions that HCPs receive of the way patients and caregivers understand the effects of gastrostomy and NIV on symptoms and quality of life; and the challenges HCPs face when caring for patients who have refused gastrostomy. More widely available guidelines for the provision of gastrostomy and advice on the best way to impart information to patients and caregivers about gastrostomy and NIV appear to be needed.