National plans and awareness campaigns as priorities for achieving global brain health.

Neurological conditions are the leading cause of death and disability combined. This public health crisis has become a global priority with the introduction of WHO's Intersectoral Global Action Plan on Epilepsy and Other Neurological Disorders 2022-2031 (IGAP). 18 months after this plan was adopted, global neurology stakeholders, including representatives of the OneNeurology Partnership (a consortium uniting global neurology organisations), take stock and advocate for urgent acceleration of IGAP implementation. Drawing on lessons from relevant global health contexts, this Health Policy identifies two priority IGAP targets to expedite national delivery of the entire 10-year plan: namely, to update national policies and plans, and to create awareness campaigns and advocacy programmes for neurological conditions and brain health. To ensure rapid attainment of the identified priority targets, six strategic drivers are proposed: universal community awareness, integrated neurology approaches, intersectoral governance, regionally coordinated IGAP domestication, lived experience-informed policy making, and neurological mainstreaming (advocating to embed brain health into broader policy agendas). Contextualised with globally emerging IGAP-directed efforts and key considerations for intersectoral policy design, this novel framework provides actionable recommendations for policy makers and IGAP implementation partners. Timely, synergistic pursuit of the six drivers might aid WHO member states in cultivating public awareness and policy structures required for successful intersectoral roll-out of IGAP by 2031, paving the way towards brain health for all.

Global synergistic actions to improve brain health for human development.

The global burden of neurological disorders is substantial and increasing, especially in low-resource settings. The current increased global interest in brain health and its impact on population wellbeing and economic growth, highlighted in the World Health Organization's new Intersectoral Global Action Plan on Epilepsy and other Neurological Disorders 2022-2031, presents an opportunity to rethink the delivery of neurological services. In this Perspective, we highlight the global burden of neurological disorders and propose pragmatic solutions to enhance neurological health, with an emphasis on building global synergies and fostering a 'neurological revolution' across four key pillars - surveillance, prevention, acute care and rehabilitation - termed the neurological quadrangle. Innovative strategies for achieving this transformation include the recognition and promotion of holistic, spiritual and planetary health. These strategies can be deployed through co-design and co-implementation to create equitable and inclusive access to services for the promotion, protection and recovery of neurological health in all human populations across the life course.

The Impact of Inherited Retinal Diseases in the United States of America (US) and Canada from a Cost-of-Illness Perspective.

OBJECTIVE: To estimate the annual cost of inherited retinal diseases (IRDs) in the United States of America (US) and Canada from a societal perspective - including costs to the health system, individual and family productivity costs, lost wellbeing and other societal economic costs - by setting and payer. Findings will inform the need for policy action to mitigate the impact of IRDs. METHODS: The costs of IRDs were estimated using a cost-of-illness methodology, based on the prevalence of IRDs in each country. Intangible costs of reduced wellbeing were also estimated using disability-adjusted life years which were then converted to monetary values using the value of a statistical life. RESULTS: Using base prevalence rates, total costs attributable to IRDs in the US were estimated to range between US$13,414.0 and US$31,797.4 million in 2019, comprising both economic costs (between US$4,982 and US$11,753.9 million; 37% of total costs) and wellbeing costs (between US$8,431.7 and US$20,043.6 million; 63%). Total costs attributable to IRDs in Canada were estimated to range between CAN$1637.8 and CAN$6687.5 million in 2019, comprising both economic costs (between CAN$566.6 and CAN$2,305.7 million; 34%) and wellbeing costs (between CAN$1,071.4 and CAN$4,381.9 million; 66% of total costs). CONCLUSION: The impact of IRDs in the US and Canada is substantial when considering both economic costs and reduced wellbeing. The wellbeing costs due to IRDs in the US and Canada are considerable, accounting for over 60% of total costs. Vision loss from IRDs often manifests in childhood, meaning some people live with vision impairment and blindness for their whole lives. Further research into current and emerging cost-effective therapies and interventions is required given the substantial economic burden faced by those living with vision loss.

The Impact of Inherited Retinal Diseases in the Republic of Ireland (ROI) and the United Kingdom (UK) from a Cost-of-Illness Perspective.

To date, there has been a global lack of data regarding the prevalence of conditions falling under the Inherited Retinal Diseases (IRD) classification, the impact on the individuals and families affected, and the cost burden to economies. The absence of an international patient registry, and equitable access to genetic testing, compounds this matter. The resulting incomplete knowledge of the impact of IRDs hinders the development and commissioning of clinical services, provision of treatments, and planning and implementation of clinical trials. Thus, there is a need for stronger evidence to support value for money to regulatory bodies for treatments approved, and progressing through clinical trials. To ensure a strategic approach to future research and service provision, it is necessary to learn more about the IRD landscape. This review highlights two recent cost-of-illness reports on the socio-economic impact of 10 IRDs in the Republic of Ireland (ROI) and the United Kingdom (UK), which demonstrate the comprehensive impact of IRDs on individuals affected, their families, friends and society. Total costs attributable to IRDs in the ROI were estimated to be £42.6 million in 2019, comprising economic (£28.8 million) and wellbeing costs (£13.8 million). Wellbeing costs were estimated using the World Health Organization (WHO) burden of disease methodology, a non-financial approach, where pain, suffering and premature mortality are measured in terms of disability-adjusted-life-years (DALYs). In the UK, wellbeing costs attributable to IRDs were £196.1 million, and economic costs were £327.2 million amounting to £523.3 million total costs in 2019. Accounting for over one-third of total costs, the wellbeing burden of persons affected by IRDs should be emphasized and factored into reimbursement processes for therapies and care pathways. This targeted review presents the most current and relevant data on IRD prevalence in the ROI and the UK, and the impacts (financial and non-financial) of IRDs in terms of diagnosis, wellbeing, employment, formal and informal care, health system costs, deadweight losses and issues surrounding payers and reimbursement. This review demonstrates IRD patients and their families have common issues including, the need for timely equitable access to genetic testing and counselling, equality in accessing employment, and a revision of the assessment process for reimbursement of therapies currently focused on the cost-of-illness to the healthcare system. This review reveals that IRD patients do not frequently engage the healthcare system and as such suggests a cost-of-illness model from a societal perspective may be a better format.

Brain-Derived Neurotrophic Factor as a Treatment Option for Retinal Degeneration.

This review discusses the therapeutic potential of brain-derived neurotrophic factor (BDNF) for retinal degeneration. BDNF, nerve growth factor (NGF), neurotrophin 3 (NT-3) and NT-4/NT-5 belong to the neurotrophin family. These neuronal modulators activate a common receptor and a specific tropomyosin-related kinase (Trk) receptor. BDNF was identified as a photoreceptor protectant in models of retinal degeneration as early as 1992. However, development of effective therapeutics that exploit this pathway has been difficult due to challenges in sustaining therapeutic levels in the retina.

Histologic Characterization of Retina Neuroglia Modifications in Diabetic Zucker Diabetic Fatty Rats.

Purpose: The purpose of this study was to characterize retinal degenerative morphologic modifications in Zucker Diabetic Fatty (ZDF) rats, a genetic model of type 2 diabetes, by histologic and immunohistochemical evaluation. Methods: Male lean (?/+; n = 10) and ZDF (fa/fa; n = 20) rats were used. At 24 weeks of age, body weights and blood glucose levels were determined. Eyes were removed and processed for paraffin wax embedding. Sections through the optic disc were stained for hematoxylin and eosin or immunostained for TUNEL, advanced glycation end products (AGEs), glial fibrillary acidic protein (GFAP), glutamate/aspartate transporter (GLAST), isolectin B4, recoverin, retinal pigment epithelium-specific 65-kDa protein, rhodopsin, vimentin, and zonula occludens protein 1. Retinal morphometry, cell counts, glial activation degree and immunoreactivity of AGEs and GLAST were also determined. Results: ZDF rats were observed to be diabetic from week 9 and by week 24. These animals showed retinal morphologic degenerative changes, increased neuroretinal thickness, and decreased number of nuclei. Glial cells activation with massive GFAP upregulation was present. Cellular morphologic modifications were also observed. GLAST immunofluorescence was decreased, whereas AGEs were increased in comparison with lean rats. Conclusions: Spontaneous development of diabetes in ZDF rats results in neuroglia morphologic degenerative changes at 24 weeks of age. This animal model may be useful to understand the pathogenesis of diabetic retinopathy and to screen neuroprotective drugs in diabetes.

BH4-Mediated Enhancement of Endothelial Nitric Oxide Synthase Activity Reduces Hyperoxia-Induced Endothelial Damage and Preserves Vascular Integrity in the Neonate.

Purpose: Endothelial nitric oxide synthase (eNOS)-derived nitric oxide (NO) has important vasoprotective functions that are compromised in the vasodegenerative phase of retinopathy of prematurity, owing to hyperoxia-induced depletion of the essential NOS cofactor BH4. Because modulating eNOS function can be beneficial or detrimental, our aim was to investigate the effect of BH4 supplementation on eNOS function and vascular regression in hyperoxia. Methods: Endothelial-specific eNOS-green fluorescent protein (GFP) overexpressing mice at postnatal day 7 (P7) were exposed to hyperoxia for 48 hours in the presence or absence of supplemental BH4, achieved by administration of sepiapterin, a stable BH4 precursor. Tissue was collected either for retinal flat mounts that were stained with lectin to determine the extent of vessel coverage or for analysis of BH4 by high-performance liquid chromatography, nitrotyrosine (NT) marker by Western blotting, VEGF expression by ELISA, and NOS activity by arginine-to-citrulline conversion. Primary retinal microvascular endothelial cells (RMEC) were similarly treated, and hyperoxia-induced damage was determined. Results: Sepiapterin effectively enhanced BH4 levels in hyperoxia-exposed retinas and brains, elevated NOS activity, and reduced NT-modified protein, leading to reversal of the exacerbated vasoregression observed in the presence of eNOS overexpression. In RMECs, hyperoxia-mediated depletion of BH4 dysregulated the redox balance by reducing nitrite and elevating superoxide and impaired proliferative ability. BH4 supplementation restored normal RMEC proliferation in vitro and also in vivo, providing a mechanistic link with the enhanced vascular coverage in eNOS-GFP retinas. Conclusions: These results demonstrate that BH4 supplementation corrects hyperoxia-induced RMEC dysfunction and preserves vascular integrity by enhancing eNOS function.

A sustained release formulation of novel quininib-hyaluronan microneedles inhibits angiogenesis and retinal vascular permeability in vivo.

Pathologic neovascularisation and ocular permeability are hallmarks of proliferative diabetic retinopathy and age-related macular degeneration. Current pharmacologic interventions targeting VEGF are effective in only 30-60% of patients and require multiple intraocular injections associated with iatrogenic infection. Thus, our goal is to develop novel small molecule drugs that are VEGF-independent are amenable to sustained ocular-release, and which reduce retinal angiogenesis and retinal vascular permeability. Here, the anti-angiogenic drug quininib was formulated into hyaluronan (HA) microneedles whose safety and efficacy was evaluated in vivo. Quininib-HA microneedles were formulated via desolvation from quininib-HA solution and subsequent cross-linking with 4-arm-PEG-amine prior to freeze-drying. Scanning electron microscopy revealed hollow needle-shaped particle ultrastructure, with a zeta potential of -35.5mV determined by electrophoretic light scattering. The incorporation efficiency and pharmacokinetic profile of quininib released in vitro from the microneedles was quantified by HPLC. Quininib incorporation into these microneedles was 90%. In vitro, 20% quininib was released over 4months; or in the presence of increasing concentrations of hyaluronidase, 60% incorporated quininib was released over 4months. Zebrafish hyaloid vasculature assays demonstrated quininib released from these microneedles significantly (p<0.0001) inhibited ocular developmental angiogenesis compared to control. Sustained amelioration of retinal vascular permeability (RVP) was demonstrated using a bespoke cysteinyl leukotriene induced rodent model. Quininib-HA microparticles significantly inhibited RVP in Brown Norway rats one month after administration compared to neat quininib control (p=0.0071). In summary, quininib-HA microneedles allow for sustained release of quininib; are safe in vivo and quininib released from these microneedles effectively inhibits angiogenesis and RVP in vivo.

Phenotype-based Discovery of 2-[(E)-2-(Quinolin-2-yl)vinyl]phenol as a Novel Regulator of Ocular Angiogenesis.

Retinal angiogenesis is tightly regulated to meet oxygenation and nutritional requirements. In diseases such as proliferative diabetic retinopathy and neovascular age-related macular degeneration, uncontrolled angiogenesis can lead to blindness. Our goal is to better understand the molecular processes controlling retinal angiogenesis and discover novel drugs that inhibit retinal neovascularization. Phenotype-based chemical screens were performed using the ChemBridge Diverset(TM)library and inhibition of hyaloid vessel angiogenesis in Tg(fli1:EGFP) zebrafish. 2-[(E)-2-(Quinolin-2-yl)vinyl]phenol, (quininib) robustly inhibits developmental angiogenesis at 4-10 µmin zebrafish and significantly inhibits angiogenic tubule formation in HMEC-1 cells, angiogenic sprouting in aortic ring explants, and retinal revascularization in oxygen-induced retinopathy mice. Quininib is well tolerated in zebrafish, human cell lines, and murine eyes. Profiling screens of 153 angiogenic and inflammatory targets revealed that quininib does not directly target VEGF receptors but antagonizes cysteinyl leukotriene receptors 1 and 2 (CysLT1-2) at micromolar IC50values. In summary, quininib is a novel anti-angiogenic small-molecule CysLT receptor antagonist. Quininib inhibits angiogenesis in a range of cell and tissue systems, revealing novel physiological roles for CysLT signaling. Quininib has potential as a novel therapeutic agent to treat ocular neovascular pathologies and may complement current anti-VEGF biological agents.