Peptide-based approaches to directly target alpha-synuclein in Parkinson's disease.

Peptides and their mimetics are increasingly recognised as drug-like molecules, particularly for intracellular protein-protein interactions too large for inhibition by small molecules, and inaccessible to larger biologics. In the past two decades, evidence associating the misfolding and aggregation of alpha-synuclein strongly implicates this protein in disease onset and progression of Parkinson's disease and related synucleinopathies. The subsequent formation of toxic, intracellular, Lewy body deposits, in which alpha-synuclein is a major component, is a key diagnostic hallmark of the disease. To reach their therapeutic site of action, peptides must both cross the blood-brain barrier and enter dopaminergic neurons to prevent the formation of these intracellular inclusions. In this review, we describe and summarise the current efforts made in the development of peptides and their mimetics to directly engage with alpha-synuclein with the intention of modulating aggregation, and importantly, toxicity. This is a rapidly expanding field with great socioeconomic impact; these molecules harbour significant promise as therapeutics, or as early biomarkers during prodromal disease stages, or both. As these are age-dependent conditions, an increasing global life expectancy means disease prevalence is rising. No current treatments exist to either prevent or slow disease progression. It is therefore crucial that drugs are developed for these conditions before health care and social care capacities become overrun.

"Palliative care is so much more than that": a qualitative study exploring experiences of hospice staff and bereaved carers during the COVID-19 pandemic.

Background: The way in which end-of-life care was provided changed significantly during the first 2 years of the COVID-19 pandemic. The national lockdown restrictions reduced formal care support services and increased the burden on many carers taking on the caring role for the first time. We aimed to explore decision-making about the place of care during the COVID-19 pandemic and the impact on experience from the perspectives of carers and hospice staff caring for people at the end-of-life. Methods: A qualitative study using virtual interviews was conducted between October 2020 and April 2021. Data were analyzed thematically using framework analysis, an analytical framework that enables qualitative research to be organized into defined themes derived from the research question. Findings were presented to stakeholders in policy roundtables between March 2022 and March 2023 and discussed collaboratively with staff, stakeholders, and the public to inform policy and practice change. Findings: A total of 37 participants (15 bereaved carers and 22 staff) were recruited via hospice services in England and Scotland. Four key themes were identified: (1) changing preferences relating to decision-making about the place of care and the impact at the time of death and into bereavement; (2) missed opportunities related to not being there, not having others around, and being robbed of memory-making; (3) the lone carer during a period of high intensity and reduced home support; (4) process vs. person-centered care resulting from changing rules and restrictions and prioritization of regulations over essential palliative care. Conclusion: The study provides valuable global implications for all involved in end-of-life care. Despite great efforts to provide dignified, quality care, palliative care during the pandemic changed, focusing on essential 'physical care'. The psychological suffering experienced by staff and carers may need longer-term support mechanisms put in place, which will benefit from a public health approach. Policymakers should consider improving carer identification and resources for wider end-of-life care education to support the needs of carers, health and social care staff, and citizens.

Development of a hydroxyflavone-labelled 4554W peptide probe for monitoring αS aggregation.

Parkinson's is the second most common neurodegenerative disease, with the number of individuals susceptible due to increase as a result of increasing life expectancy and a growing worldwide population. However, despite the number of individuals affected, all current treatments for PD are symptomatic-they alleviate symptoms, but do not slow disease progression. A major reason for the lack of disease-modifying treatments is that there are currently no methods to diagnose individuals during the earliest stages of the disease, nor are there any methods to monitor disease progression at a biochemical level. Herein, we have designed and evaluated a peptide-based probe to monitor αS aggregation, with a particular focus on the earliest stages of the aggregation process and the formation of oligomers. We have identified the peptide-probe K1 as being suitable for further development to be applied to number of applications including: inhibition of αS aggregation; as a probe to monitor αS aggregation, particularly at the earliest stages before Thioflavin-T is active; and a method to detect early-oligomers. With further development and in vivo validation, we anticipate this probe could be used for the early diagnosis of PD, a method to evaluate the effectiveness of potential therapeutics, and as a tool to help in the understanding of the onset and development of PD.

Anionic lipid vesicles have differential effects on the aggregation of early onset-associated α-synuclein missense mutants.

α-synuclein (αS) is the key component of synucleinopathies such as Parkinson's disease (PD), dementia with Lewy bodies, and multiple system atrophy. αS was first linked to PD through the identification of point mutations in the SNCA gene, causing single amino acid substitutions within αS and familial autosomal dominant forms of PD that profoundly accelerated disease onset by up to several decades. At least eight single-point mutations linked to familial PD (A30G/P, E46K, H50Q, G51D, and A53T/E/V) are located in proximity of the region preceding the non-ß amyloid component (preNAC) region, strongly implicating its pathogenic role in αS-mediated cytotoxicity. Furthermore, lipids are known to be important for native αS function, where they play a key role in the regulation of synaptic vesicle docking to presynaptic membranes and dopamine transmission. However, the role of lipids in the function of mutant αS is unclear. Here, we studied αS aggregation properties of WT αS and five of the most predominant single-point missense mutants associated with early onset PD in the presence of anionic 1,2-dimyristoyl-sn-glycero-3-phospho-l-serine lipid vesicles. Our results highlight significant differences between aggregation rates, the number of aggregates produced, and overall fibril morphologies of WT αS and the A30P, E46K, H50Q, G51D, and A53T missense mutants in the presence of lipid vesicles. These findings have important implications regarding the interplay between the lipids required for αS function and the individual point mutations known to accelerate PD and related diseases.

The Experiences of Informal Carers during the COVID-19 Pandemic: A Qualitative Systematic Review.

OBJECTIVES: To identify, critically appraise and synthesise the qualitative literature on the experiences of informal carers of people with long-term conditions during the COVID-19 pandemic. DESIGN: A qualitative systematic literature review. DATA SOURCES: Eight electronic databases were systematically searched (Medline, Embase, CINAHL, PubMed, PsychINFO, Web of Science, Nursing and Allied Health and ASSIA) along with Google Scholar and handsearching via secondary sources. STUDY SELECTION: Eligible studies had to include the experiences of informal carers (adults who are 65 or older), use a qualitative methodology and had to be written in English. DATA EXTRACTION AND SYNTHESIS: Retrieved papers were quality assessed using the Critical Appraisal Skills Programme qualitative checklist and ranked for quality. Thematic analysis was used to synthesise the findings. RESULTS: Fourteen studies were included, all from medical or nursing journals (n = 5 specifically gerontology). Four main themes were identified: (i) fear, (ii) uncertainty, (iii) burden and (iv) staying connected. Caregiving demands have increased for carers during the pandemic, as well as negative emotions such as fear and uncertainty. At the same time, less social support has been available, leading to concerns about carers' wellbeing and ability to cope. CONCLUSION: Carers' needs have been exacerbated by the COVID-19 pandemic. Greater practical and emotional support is needed for carers from both formal services and community sources that considers their changing needs and offers educational and emotional support for long-term wellbeing. Strengths and Limitations: (1) This is the first systematic review to explore in depth the experiences of informal carers caring for people with a range of long-term conditions and from an international context. (2) The review includes an analysis of the quality of the studies, as well as a study of their relative contributions. (3) Further research is needed to explore the physical, emotional and financial impact of the pandemic for bereaved carers which is not captured in this review due to the lack of empirical data available at the time of review.

Library-Derived Peptide Aggregation Modulators of Parkinson's Disease Early-Onset α-Synuclein Variants.

Parkinson's Disease (PD) is characterized by the accumulation of Lewy bodies in dopaminergic neurons. The main protein component of Lewy bodies, α-synuclein (αS), is also firmly linked to PD through the identification of a number of single point mutations that are autosomal dominant for early-onset disease. Consequently, the misfolding and subsequent aggregation of αS is thought to be a key stage in the development and progression of PD. Therefore, modulating the aggregation pathway of αS is an attractive therapeutic target. Owing to the fact that all but one of the familial mutations is located in the preNAC 45-54 region of αS, we previously designed a semi-rational library using this sequence as a design scaffold. The 45-54 peptide library was screened using a protein-fragment complementation assay approach, leading to the identification of the 4554W peptide. The peptide was subsequently found to be effective in inhibiting primary nucleation of αS, the earliest stage of the aggregation pathway. Here, we build upon this previous work by screening the same 45-54 library against five of the known αS single-point mutants that are associated with early-onset PD (A30P, E46K, H50Q, G51D, and A53T). These point mutations lead to a rapid acceleration of PD pathology by altering either the rate or type of aggregates formed. All ultimately lead to earlier disease onset and were therefore used to enforce increased assay stringency during the library screening process. The ultimate aim was to identify a peptide that is effective against not only the familial αS variant from which it has been selected but that is also effective against WT αS. Screening resulted in five peptides that shared common residues at some positions, while deviating at others. All reduced aggregation of the respective target, with several also identified to be effective at reducing aggregation when incubated with other variants. In addition, our results demonstrate that a previously optimized peptide, 4554W(N6A), is highly effective against not only WT αS but also several of the single-point mutant forms and hence is a suitable baseline for further work toward a PD therapeutic.

Factors influencing adult carer support planning for unpaid caregiving at the end of life in Scotland: Qualitative insights from triangulated interviews and focus groups.

Caring for a relative or friend at the end of life can be rewarding but all-encompassing. These caregivers are often not identified, meaning their diverse needs remain unmet, and the lack of assessment, support and planning increases the likelihood of crisis and burnout. The Carers (Scotland) Act 2016 places responsibility on local authorities to implement such a plan, which will be fast-tracked for carers supporting someone at the end of life. Our research described the factors which might influence this planning, triangulating primary focus groups with 15 carers and secondary qualitative data from transcripts with 30 carers, all of whom who had looked after someone with a terminal illness. Analysis was iterative, and constant comparative analysis of the secondary data informed the primary focus groups. Three main themes were identified; 1. The importance of early identification as a carer to enable timely assessment and support. 2. Carers experience isolation and loneliness which limits opportunities for support. 3. Responding in a timely fashion to carer assessment and support is vital to avoid crises. This research confirms that identifying carers early in the illness trajectory, ideally at diagnosis, is vital to avoid carer burnout. Health and social care providers have a key role in identification and should ensure, where possible, that carer needs are dynamically assessed, supported and documented. Finally, caring does not end after death, it extends into bereavement. Thus, we need to consider system and cultural change to ensure the experiences and needs of carers are addressed and valued.

A Downsized and Optimised Intracellular Library-Derived Peptide Prevents Alpha-Synuclein Primary Nucleation and Toxicity Without Impacting Upon Lipid Binding.

Misfolding and aggregation of alpha-synuclein (αS) within dopaminergic neurons is a key factor in the development and progression of a group of age-related neurodegenerative diseases, termed synucleinopathies, that include Parkinson's disease (PD). We previously derived a peptide inhibitor from a 209,952-member intracellular library screen by employing the preNAC region (45-54) as a design template. At least six single-point mutations firmly linked to early-onset Parkinson's disease (E46K, H50Q, G51D, A53T/E/V) are located within this region, strongly implicating a pathogenic role within αS that leads to increased cytotoxicity. A library-derived ten residue peptide, 4554W, was consequently shown to block αS aggregation at the point of primary nucleation via lipid induction, inhibiting its conversion into downstream cytotoxic species. Here we couple truncation with a full alanine scan analysis, to establish the effect upon the αS aggregation pathway relative to 4554W. This revealed the precise residues responsible for eliciting inhibitory interaction and function, as well as those potentially amenable to modification or functionalisation. We find that modification N6A combined with N-terminal truncation results in a peptide of significantly increased efficacy. Importantly, our data demonstrate that the peptide does not directly disrupt αS lipid-binding, a desirable trait since antagonists of αS aggregation and toxicity should not impede association with small synaptic neurotransmitter vesicles, and thus not disrupt dopaminergic vesicle fusion and recycling. This work paves the way toward the major aim of deriving a highly potent peptide antagonist of αS pathogenicity without impacting on native αS function.

Palliative care research promotion in policy and practice: a knowledge exchange process.

In palliative care, as in many areas of medicine, there is a considerable amount of research conducted that makes sound recommendations but does not result consistently in improved care. For instance, though palliative care has been shown to benefit all people with a life-threatening illness, its main reach continues to be for those with cancer. Drawing on relational models of research use, we set out to engage policy-makers, educators, clinicians, commissioners and service providers in a knowledge exchange process to identify implications of research for Scottish palliative care priorities. First, we mapped the existing palliative care research evidence in Scotland. We then organised evidence review meetings and a wider stakeholder event where research producers and users came together to coproduce implications of the evidence for policy, education and practice. We used questionnaires and key stakeholder feedback meetings to explore impacts of this process on research uptake and use immediately after the events and over time. In this paper, we reflect on this knowledge exchange process and the broader context in which it was set. We found that participation fostered relationships and led to a rich and enthusiastic exploration of research evidence from multiple perspectives. Potential impacts relating to earlier identification for palliative care, education and need-based commissioning ensued. We make suggestions to guide replication.

How many people will need palliative care in Scotland by 2040? A mixed-method study of projected palliative care need and recommendations for service delivery.

OBJECTIVE: To estimate future palliative care need and complexity of need in Scotland, and to identify priorities for future service delivery. DESIGN: We estimated the prevalence of palliative care need by analysing the proportion of deaths from defined chronic progressive illnesses. We described linear projections up to 2040 using national death registry data and official mortality forecasts. An expert consultation and subsequent online consensus survey generated recommendations on meeting future palliative care need. SETTING: Scotland, population of 5.4 million. PARTICIPANTS: All decedents in Scotland over 11 years (2007 to 2017). The consultation had 34 participants; 24 completed the consensus survey. PRIMARY AND SECONDARY OUTCOMES: Estimates of past and future palliative care need in Scotland from 2007 up to 2040. Multimorbidity was operationalised as two or more registered causes of death from different disease groups (cancer, organ failure, dementia, other). Consultation and survey data were analysed descriptively. RESULTS: We project that by 2040, the number of people requiring palliative care will increase by at least 14%; and by 20% if we factor in multimorbidity. The number of people dying from multiple diseases associated with different disease groups is projected to increase from 27% of all deaths in 2017 to 43% by 2040. To address increased need and complexity, experts prioritised sustained investment in a national digital platform, roll-out of integrated electronic health and social care records; and approaches that remain person-centred. CONCLUSIONS: By 2040 more people in Scotland are projected to die with palliative care needs, and the complexity of need will increase markedly. Service delivery models must adapt to serve growing demand and complexity associated with dying from multiple diseases from different disease groups. We need sustained investment in secure, accessible, integrated and person-centred health and social care digital systems, to improve care coordination and optimise palliative care for people across care settings.

The Library Derived 4554W Peptide Inhibits Primary Nucleation of α-Synuclein.

Aggregation of α-Synuclein (αS) is widely regarded as a key factor in neuronal cell death, leading to a wide range of synucleinopathies, including Parkinson's Disease. Development of therapeutics has therefore focused on inhibiting aggregation of αS into toxic forms. One such inhibitor, based on the preNAC region αS45-54 (4554W), was identified using an intracellular peptide library screen, and subsequently shown to both inhibit formation of αS aggregates while simultaneously lowering toxicity. Subsequent efforts have sought to determine the mode of 4554W action. In particular, and consistent with the fact that both target and peptide are co-produced during library screening, we find that the peptide inhibits primary nucleation of αS, but does not modulate downstream elongation or secondary nucleation events. These findings hold significant promise towards mechanistic understanding and development of molecules that can module the first steps in αS aggregation towards novel treatments for Parkinson's disease and related synucleinopathies.

Insights Into Peptide Inhibition of Alpha-Synuclein Aggregation.

α-Synuclein (aSyn) aggregation is an attractive target for therapeutic development for a range of neurodegenerative conditions, collectively termed synucleinopathies. Here, we probe the mechanism of action of a peptide 4554W, (KDGIVNGVKA), previously identified through intracellular library screening, to prevent aSyn aggregation and associated toxicity. We utilize NMR to probe association and identify that 4554W associates with a "partially aggregated" form of aSyn, with enhanced association occurring over time. We also report the ability of 4554W to undergo modification through deamidation of the central asparagine residue, occurring on the same timescale as aSyn aggregation in vitro, with peptide modification enhancing its association with aSyn. Additionally, we report that 4554W can act to reduce fibril formation of five Parkinson's disease associated aSyn mutants. Inhibitory peptide binding to partially aggregated forms of aSyn, as identified here, is particularly attractive from a therapeutic perspective, as it would eliminate the need to administer the therapy at pre-aggregation stages, which are difficult to diagnose. Taken together the data suggest that 4554W could be a suitable candidate for future therapeutic development against wild-type, and most mutant aSyn aggregation.

A series of helical α-synuclein fibril polymorphs are populated in the presence of lipid vesicles.

α-Synuclein (αS) deposition is a defining characteristic of Parkinson's disease (PD) pathology, and other synucleinopathies. αS aggregates in disease, leading to the generation of neuronal inclusions known as Lewy bodies. These accumulate in the cytoplasmic space of dopaminergic neurons in the substantia nigra pars compacta region of the brain, causing cell death, resulting in decreased dopamine levels, and ultimately PD symptoms. To date, a significant proportion of structural information has arisen from in vitro studies using recombinantly purified forms of the protein, often failing to acknowledge that αS is natively located in the presence of phospholipids, where it likely plays a direct role in regulating synaptic vesicle function and neurotransmission. Here we present a series of macromolecular αS assemblies not previously described that form in the presence of lipid vesicles. These fibrillar structures are striking in both their large size relative to those previously reported and by their varying helical content, from ribbons to wave-like helices of long pitch shortening to those more compact and bulkier. These studies provide the foundation for more detailed structural analysis, and may offer new possibilities to further define disease-relevant versions of the protein that are accessible to pharmacological intervention.

Electronic care coordination systems for people with advanced progressive illness: a mixed-methods evaluation in Scottish primary care.

BACKGROUND: Electronic care coordination systems, known as the Key Information Summary (KIS) in Scotland, enable the creation of shared electronic records available across healthcare settings. A KIS provides clinicians with essential information to guide decision making for people likely to need emergency or out-of-hours care. AIM: To estimate the proportion of people with an advanced progressive illness with a KIS by the time of death, to examine when planning information is documented, and suggest improvements for electronic care coordination systems. DESIGN AND SETTING: This was a mixed-methods study involving 18 diverse general practices in Scotland. METHOD: Retrospective review of medical records of patients who died in 2017, and semi-structured interviews with healthcare professionals were conducted. RESULTS: Data on 1304 decedents were collected. Of those with an advanced progressive illness (79%, n = 1034), 69% (n = 712) had a KIS. These were started a median of 45 weeks before death. People with cancer were most likely to have a KIS (80%, n = 288), and those with organ failure least likely (47%, n = 125). Overall, 68% (n = 482) of KIS included resuscitation status and 55% (n = 390) preferred place of care. People with a KIS were more likely to die in the community compared to those without one (61% versus 30%). Most KIS were considered useful/highly useful. Up-to-date free-text information within the KIS was valued highly. CONCLUSION: In Scotland, most people with an advanced progressive illness have an electronic care coordination record by the time of death. This is an achievement. To improve further, better informal carer information, regular updating, and a focus on generating a KIS for people with organ failure is warranted.

The impact of population ageing on end-of-life care in Scotland: projections of place of death and recommendations for future service provision.

BACKGROUND: Global annual deaths are rising. It is essential to examine where future deaths may occur to facilitate decisions regarding future service provision and resource allocation. AIMS: To project where people will die from 2017 to 2040 in an ageing country with advanced integrated palliative care, and to prioritise recommendations based on these trends. METHODS: Population-based trend analysis of place of death for people that died in Scotland (2004-2016) and projections using simple linear modelling (2017-2040); Transparent Expert Consultation to prioritise recommendations in response to projections. RESULTS: Deaths are projected to increase by 15.9% from 56,728 in 2016 (32.8% aged 85+ years) to 65,757 deaths in 2040 (45% aged 85+ years). Between 2004 and 2016, proportions of home and care home deaths increased (19.8-23.4% and 14.5-18.8%), while the proportion of hospital deaths declined (58.0-50.1%). If current trends continue, the numbers of deaths at home and in care homes will increase, and two-thirds will die outside hospital by 2040. To sustain current trends, priorities include: 1) to increase and upskill a community health and social care workforce through education, training and valuing of care work; 2) to build community care capacity through informal carer support and community engagement; 3) to stimulate a realistic public debate on death, dying and sustainable funding. CONCLUSION: To sustain current trends, health and social care provision in the community needs to grow to support nearly 60% more people at the end-of-life by 2040; otherwise hospital deaths will increase.

Alpha-synuclein structure and Parkinson's disease - lessons and emerging principles.

Alpha-synuclein (αS) is the major constituent of Lewy bodies and a pathogenic hallmark of all synucleinopathathies, including Parkinson's disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA). All diseases are determined by αS aggregate deposition but can be separated into distinct pathological phenotypes and diagnostic criteria. Here we attempt to reinterpret the literature, particularly in terms of how αS structure may relate to pathology. We do so in the context of a rapidly evolving field, taking into account newly revealed structural information on both native and pathogenic forms of the αS protein, including recent solid state NMR and cryoEM fibril structures. We discuss how these new findings impact on current understanding of αS and PD, and where this information may direct the field.

Excitation-Energy-Dependent Molecular Beacon Detects Early Stage Neurotoxic Aß Aggregates in the Presence of Cortical Neurons.

There is now crucial medical importance placed on understanding the role of early stage, subvisible protein aggregation, particularly in neurodegenerative disease. While there are strategies for detecting such aggregates in vitro, there is no approach at present that can detect these toxic species associated with cells and specific subcellular compartments. We have exploited excitation-energy-dependent fluorescence edge-shift of recombinant protein labeled with a molecular beacon, to provide a sensitive read out for the presence of subvisible protein aggregates. To demonstrate the potential utility of the approach, we examine the major peptide associated with the initiation of Alzheimer's disease, amyloid ß-protein (Aß) at a patho-physiologically relevant concentration in mouse cortical neurons. Using our approach, we find preliminary evidence that subvisible Aß aggregates are detected at specific subcellular regions and that neurons drive the formation of specific Aß aggregate conformations. These findings therefore demonstrate the potential of a novel fluorescence-based approach for detecting and imaging protein aggregates in a cellular context, which can be used to sensitively probe the association of early stage toxic protein aggregates within subcellular compartments.