Memantine treatment in patients with moderate to severe Alzheimer disease already receiving donepezil: a randomized controlled trial

Exploring the Mechanisms and Therapeutic Approaches of Mitochondrial Dysfunction in Alzheimer's Disease: An Educational Literature Review

Alzheimer's disease (AD) presents a significant challenge to global health. It is characterized by progressive cognitive deterioration and increased rates of morbidity and mortality among older adults. Among the various pathophysiologies of AD, mitochondrial dysfunction, encompassing conditions such as increased reactive oxygen production, dysregulated calcium homeostasis, and impaired mitochondrial dynamics, plays a pivotal role. This review comprehensively investigates the mechanisms of mitochondrial dysfunction in AD, focusing on aspects such as glucose metabolism impairment, mitochondrial bioenergetics, calcium signaling, protein tau and amyloid-beta-associated synapse dysfunction, mitophagy, aging, inflammation, mitochondrial DNA, mitochondria-localized microRNAs, genetics, hormones, and the electron transport chain and Krebs cycle. While lecanemab is the only FDA-approved medication to treat AD, we explore various therapeutic modalities for mitigating mitochondrial dysfunction in AD, including antioxidant drugs, antidiabetic agents, acetylcholinesterase inhibitors (FDA-approved to manage symptoms), nutritional supplements, natural products, phenylpropanoids, vaccines, exercise, and other potential treatments.

Safety and Toxicity of Qi-Fu Yin, a Classical Traditional Chinese Medicine Prescription: A Nonclinical Research

Qi-Fu-Yin (QFY) is a classic prescription in traditional Chinese medicine for treating dementia, such as Alzheimer's disease, but its safety has not yet been investigated. The purpose of this study was to assess the safety pharmacology and toxicology of QFY extract powder (QFYEP) to provide guidance for clinical trials or applications of QFY and its innovative formulations. The safety pharmacology of QFYEP on the central nervous system and respiratory system and its acute toxicity and 26-week repeated-dose toxicity were evaluated in Sprague-Dawley (SD) rats. The safety pharmacology of QFYEP on the cardiovascular system was evaluated in beagle dogs. Additionally, the genotoxicity of QFYEP was assessed using the Ames test, an in vitro chromosome aberration test, and an in vivo micronucleus test. Under the experimental doses, no effects of QFYEP on the central nervous system or respiratory system were detected, no acute toxicity, long-term toxicity, or genotoxic effects of QFYEP were observed at any of the experimental doses. Specifically, the no-observed adverse-effect level (NOAEL) for the 26-week rat toxicity study was 10 g/kg/day (approximately 42 times the intended human clinical dose). The only finding of note was dose-related vomiting and elevated blood pressure in the dog safety pharmacology study at oral doses 5.2- to 10.4- times the proposed clinical dose. In conclusion, this safety package of studies supports development of QFYEP in the clinic but with monitoring for any cardiovascular changes.

Efficient strategy for alleviating neuronal apoptosis and oxidative stress damage of Alzheimer's disease through dual targeting BCL-2 gene promoter i-motif and β-amyloid

Alzheimer's disease (AD) is a severe neurodegenerative disorder characterized by abnormal metabolism of β-amyloid (Aβ) precursor proteins and neuronal apoptosis, ultimately leading to cognitive dysfunction. The pathogenesis of AD is complex, and current single-target therapies are not effective in preventing the rapid progression of AD, which highlights the urgent need for developing multi-target drugs. In this study, a series of compounds were synthesized through a multi-targeting ligand strategy. After extensive screening and evaluation, we found a lead compound B14, which showed excellent dual targeting ability for effectively alleviating neuronal apoptosis and oxidative stress damage of AD. In our molecular and cellular level experiments, B14 could target and stabilize the i-motif structure formed on the BCL-2 promoter to upregulate BCL-2 expression, which could also bind to Aβ and inhibit its deposition. In the Aβ1-42-induced cell model, B14 could maintain mitochondrial function and number, regulate intracellular reactive oxygen species (ROS) and Ca2+ metabolism disorders, and effectively reduce Aβ1-42-induced apoptosis. Further studies showed that B14 also exhibited good ability to cross the blood-brain barrier (BBB), which significantly improved learning memory and cognitive deficits, reduced brain Aβ plaques, alleviated inflammation and restored oxidative stress markers in APP/PS1 mice. Our findings provide an innovative strategy of dual targeting BCL-2 promoter i-motif for transcriptional regulation and Aβ aggregation synergistically for mitigating AD pathologies. B14 represents a promising multi-target lead compound with a good potential for further development for AD treatment.

KCTD20 suppression mitigates excitotoxicity in tauopathy patient organoids

Excitotoxicity is a major pathologic mechanism in patients with tauopathy and other neurodegenerative diseases. However, the key neurotoxic drivers and the most effective strategies for mitigating these degenerative processes are unclear. Here, we show that glutamate treatment of induced pluripotent stem cell (iPSC)-derived cerebral organoids induces tau oligomerization and neurodegeneration and that these phenotypes are enhanced in organoids derived from tauopathy patients. Using a genome-wide CRISPR interference (CRISPRi) screen, we find that the suppression of KCTD20 potently ameliorates tau pathology and neurodegeneration in glutamate-treated organoids and mice, as well as in transgenic mice overexpressing mutant human tau. KCTD20 suppression reduces oligomeric tau and improves neuron survival by activating lysosomal exocytosis, which clears pathological tau. Our results show that glutamate signaling can induce neuronal tau pathology and identify KCTD20 suppression and lysosomal exocytosis as effective strategies for clearing neurotoxic tau species.

Patient management pathways in dementia - Resource utilisation, diagnosis and drug treatment in the Stockholm region, Sweden

BACKGROUND

New diagnostic and therapeutic options for Alzheimer's disease are beginning to be introduced and expected igto become more widely available in the coming years. Improved understanding of current pathways in diagnosis and initial care of patients with dementia can help inform choices around how best to integrate new technologies in existing care structures.

OBJECTIVES

The aim of this study is to describe the care management pathways defined by the involvement of specialist and primary care for individuals with newly diagnosed dementia. It also seeks to characterise individuals in different management pathways based on resource use prior to diagnosis, the type of dementia diagnosis received, and the proportion who receive symptomatic anti-dementia drug treatment.

DESIGN

Observational cohort study SETTING: Stockholm region, Sweden.

PARTICIPANTS

All newly diagnosed dementia cases between 1st January 2018 to 30th June 2020 (n = 9,781). Dementia diagnoses in primary care were based on Regional Stockholm health care database and diagnoses in specialist care were based on the National Patient Register in Sweden.

MEASUREMENTS

Care management pathways were categorized into three groups: primary care only (diagnosed and followed up in primary care), specialist, no follow-up (diagnosed in specialist care but not followed up in specialist care), and specialist with follow-up (diagnosed and followed up in specialist care). These classifications were based on patients' care episodes from the date of diagnosis and the subsequent 18 months. age at diagnosis, resource utilisation one-year prior diagnosis and diagnosis given and symptomatic anti-dementia treatment 18 months after initial diagnosis.

RESULTS

A total of 9,781 newly diagnosed dementia cases were identified. In the 18 months following diagnosis, 63 % of patients were diagnosed either partly or fully in specialist care, while 37 % were diagnosed solely in primary care. Patients diagnosed and managed only in primary care were older, spent more days in hospital, and received more social care in the year preceding their diagnosis. Their total care costs were also the highest. Alzheimer's disease was the most common diagnosis (48 %), while 27 % had an unspecified dementia diagnosis, varying by care setting (61 % for patients managed in primary care only and 6 % for patients diagnosed and followed up in specialist care). Overall, 47 % of patients received symptomatic anti-dementia treatment, with the highest share for patients diagnosed and followed up in specialist care (73 %) and the lowest in primary care only (19 %). Diagnosis varied by age and care setting Alzheimer's was most common in settings involving specialist care, whereas unspecified dementia was more common in primary care only regardless of age.

CONCLUSION

The findings that patients managed exclusively in primary care were older, had higher pre-diagnosis resource utilisation, and were less likely to receive specific diagnoses or anti-dementia treatments highlight the crucial role of primary care in diagnosing and managing dementia among older individuals with complex needs. Further research is needed to explore primary care's role in diagnosis and treatment across diverse healthcare systems. Future research is needed to explore whether and how new diagnostic tools and treatment for AD could facilitate timely diagnosis and care for older individuals with dementia in primary care.

Memantine and amantadine KLVFF peptide conjugates: Synthesis, structure determination, amyloid-β interaction and effects on recognition memory in mice

BACKGROUND

Adamantane derivatives, such as memantine (Mem) and amantadine (Ada), have distinct mechanisms and therapeutic applications. Ada is primarily utilized as an antiviral and anti-Parkinson drug without significant pro-cognitive effects, Mem is effective in various clinical conditions characterized by cognitive deficits, including Alzheimer's disease. Recent evidence highlights a neuroprotective role for Aβ monomers, suggesting that preventing their aggregation into toxic oligomers could be a promising therapeutic strategy. Based on the observation that the Lys-Leu-Val-Phe-Phe (KLVFF) peptide, can block the transition of randomly coiled Aβ monomers into toxic β-sheet aggregates, two KLVFF conjugates, the Mem-Succ-KLVFF and Ada-Succ-KLVFF were investigated.

METHODS

Peptides were synthesized by Microwave-Assisted Solid Phase Peptide Synthesis (MW-SPPS). Circular Dichroism (CD), Th-T fluorescence and Gel-Electrophoresis techniques were used to assess the inhibitory effect on Aβ42 fibrillogenesis. The formation of inclusion complexes with β-Cyclodextrin (β-CyD) was demonstrated by NMR Spectroscopy. The Novel Object Recognition (NOR) test, followed by double-blind analysis, was applied for in vivo response to compounds administration. In vitro effects on neurons were studied by MTT assay and WB analysis, whereas HR ESI-MS allowed the molecular detection on brain homogenates.

RESULTS

These compounds differently affect Aβ42 aggregation. Mem-Succ-KLVFF, and Succ-KLVFF affect pCREB levels in differentiated SH-SY5Y, a signaling pathway involved in memory processes. In the NOR test, both Mem and KLVFF exhibited pro-cognitive effects individually and synergistically when co-administered.

CONCLUSION

Structure-activity relationships are discussed, integrating in vivo results, memory-related cellular pathways, and HR-ESI-MS analyses. These findings support the therapeutic potential of these compounds in preserving cognitive function.

Safety issues of Donepezil combined with Memantine in Alzheimer's disease population: real-world pharmacovigilance

BACKGROUND

Alzheimer's disease (AD) is the most common form of dementia. The combination of Donepezil and Memantine is the only FDA-approved therapy for AD, but its adverse drug reactions (ADRs) lack systematic analysis. This study carried out drug combination analysis for AD population to provide evidence support for clinical safety of drug use.

RESEARCH DESIGN AND METHODS

Using FAERS database reports (January 2004-January 2024) with Donepezil and Memantine as primary suspected drugs, four disproportionality analysis methods - ROR, PRR, BCPNN, and EBGM - were applied to identify positive ADR signals. Subgroup analyses were conducted by age and gender.

RESULTS

A total of 712 reports were analyzed (54.6% female, 55.1% aged 65-85). Across the AD population, 42 ADRs were identified, including hypertensive crisis, hyperglycemia, hyperosmolar nonketotic syndrome, proteinuria, and hydronephrosis, many of which were newly reported. Subgroup analysis revealed prostate hypertrophy, acute kidney injury, and cerebral infarction in males, while females experienced more severe cardiovascular events, such as complete AV block and ventricular extrasystole. Additional ADRs included hyperkalemia, sinus bradycardia, and extrapyramidal disorders.

CONCLUSIONS

Despite partial consistency of combined ADRs for Donepezil and Memantine with instructions, new ADR signals emerged, with significant differences in AD subgroups.

Nanoscale drug formulations for the treatment of Alzheimer's disease progression

Alzheimer's disease (AD) is a devastating neurodegenerative disorder with no effective disease-modifying treatments. The blood-brain barrier hinders drug delivery to the brain, limiting therapeutic efficacy. Nanoparticle-based systems have emerged as promising tools to overcome these challenges. This review highlights recent advances in nanoparticle technologies for AD treatment, including liposomes, polymeric, inorganic, and biomimetic nanoparticles. These nanoparticles improve drug delivery across the blood-brain barrier, improve stability and bioavailability, and enable targeted delivery to affected brain regions. Functionalization strategies further enhance their therapeutic potential. Multifunctional nanoparticles combining therapeutic and diagnostic properties offer theranostic approaches. While progress has been made, challenges related to safety, targeting precision, and clinical translation remain. Future perspectives emphasize the need for collaborative efforts to optimize nanoparticle design, conduct rigorous studies, and accelerate the development of effective nanotherapeutics. With continued innovation, nanoparticle-based delivery systems hold great promise for revolutionizing AD treatment.

ARCH: Large-scale knowledge graph via aggregated narrative codified health records analysis

OBJECTIVE

Electronic health record (EHR) systems contain a wealth of clinical data stored as both codified data and free-text narrative notes (NLP). The complexity of EHR presents challenges in feature representation, information extraction, and uncertainty quantification. To address these challenges, we proposed an efficient Aggregated naRrative Codified Health (ARCH) records analysis to generate a large-scale knowledge graph (KG) for a comprehensive set of EHR codified and narrative features.

METHODS

Using data from 12.5 million Veterans Affairs patients, ARCH first derives embedding vectors and generates similarities along with associated p-values to measure the strength of relatedness between clinical features with statistical certainty quantification. Next, ARCH performs a sparse embedding regression to remove indirect linkage between features to build a sparse KG. Finally, ARCH was validated on various clinical tasks, including detecting known relationships between entity pairs, predicting drug side effects, disease phenotyping, as well as sub-typing Alzheimer's disease patients.

RESULTS

ARCH produces high-quality clinical embeddings and KG for over 60,000 codified and narrative EHR concepts. The KG and embeddings are visualized in the R-shiny powered web-API.3 ARCH achieved high accuracy in detecting EHR concept relationships, with AUCs of 0.926 (codified) and 0.861 (NLP) for similar EHR concepts, and 0.810 (codified) and 0.843 (NLP) for related pairs. It detected drug side effects with a 0.723 AUC, which improved to 0.826 after fine-tuning. Using both codified and NLP features, the detection power increased significantly. Compared to other methods, ARCH has superior accuracy and enhances weakly supervised phenotyping algorithms' performance. Notably, it successfully categorized Alzheimer's patients into two subgroups with varying mortality rates.

CONCLUSION

The proposed ARCH algorithm generates large-scale high-quality semantic representations and knowledge graph for both codified and NLP EHR features, useful for a wide range of predictive modeling tasks.

Recent Insights into the Neurobiology of Alzheimer's Disease and Advanced Treatment Strategies

In recent years, significant advancements have been made in understanding Alzheimer's disease from both neurobiological and clinical perspectives. Exploring the complex systems underlying AD has unveiled insights that could potentially revolutionize therapeutic approaches. Recent investigations have highlighted intricate interactions among genetic, molecular, and environmental factors in AD. Optimism arises from neurobiological advancements and diverse treatment options, potentially slowing or halting disease progression. Amyloid-beta plaques and tau protein tangles crucially influence AD onset and progression. Emerging treatments involve diverse strategies, such as approaches targeting multiple pathways involved in AD pathogenesis, such as inflammation, oxidative stress, and synaptic dysfunction pathways. Clinical trials using humanized monoclonal antibodies, focusing on immunotherapies eliminating amyloid-beta, have shown promise. Nonpharmacological interventions such as light therapy, electrical stimulation, cognitive training, physical activity, and dietary changes have drawn attention for their potential to slow cognitive aging and enhance brain health. Precision medicine, which involves tailoring therapies to individual genetic and molecular profiles, has gained traction. Ongoing research and interdisciplinary collaboration are expected to yield more effective treatments.

Development of Continuous-Flow Reactions for the Synthesis of Anti-Alzheimer Drug Memantine

Memantine hydrochloride, a non-competitive antagonist of NMDA-type glutamate receptors, is known to suppress the progression of symptoms in Alzheimer's disease. Possessing a characteristic adamantane skeleton as its core structure and an amino group at the bridgehead position, memantine was synthesized starting from acenaphthene. The synthesis involved nucleus hydrogenation of acenaphthene to perhydroacenaphthene, skeletal rearrangement of perhydroacenaphthene, nitration of 1,3-dimethyladamantane, and reduction of the nitro groups to an amino group. In each step, continuous flow reactions were investigated to achieve continuous manufacturing of memantine.

Cutting-edge Strategies for Overcoming Therapeutic Barriers in Alzheimer's Disease

Alzheimer's disease (AD) remains one of the hardest neurodegenerative diseases to treat due to its enduring cognitive deterioration and memory loss. Despite extensive research, few viable treatment approaches have been found; these are mostly due to several barriers, such as the disease's complex biology, limited pharmaceutical efficacy, and the BBB. This presentation discusses current strategies for addressing these therapeutic barriers to enhance AD treatment. Innovative drug delivery methods including liposomes, exosomes, and nanoparticles may be able to pass the blood-brain barrier and allow medicine to enter specific brain regions. These innovative strategies of medicine distribution reduce systemic side effects by improving absorption. Moreover, the development of disease-modifying treatments that target tau protein tangles, amyloid-beta plaques, and neuroinflammation offers the chance to influence the course of the illness rather than only treat its symptoms. Furthermore, gene therapy and CRISPR-Cas9 technologies have surfaced as potentially groundbreaking methods for addressing the underlying genetic defects associated with AD. Furthermore, novel approaches to patient care may involve the utilization of existing medications having neuroprotective properties, such as those for diabetes and cardiovascular conditions. Furthermore, biomarker research and personalized medicine have made individualized therapy approaches possible, ensuring that patients receive the best care possible based on their unique genetic and molecular profiles.

Stem Cells as a Novel Source for Regenerative Medicinal Applications in Alzheimer's Disease: An Update

Alzheimer's Disease (AD) is a progressive neurodegenerative disorder characterized by loss of the neurons, excessive accumulation of misfolded Aβ and Tau proteins, and degeneration of neural synapses, primarily occurring in the neocortex and the hippocampus regions of the brain. AD Progression is marked by cognitive deterioration, memory decline, disorientation, and loss of problem-solving skills, as well as language. Due to limited comprehension of the factors contributing to AD and its severity due to neuronal loss, even today, the medications approved by the U.S. Food and Drug Administration (FDA) are not precisely efficient and curative. Stem cells possess great potential in aiding AD due to their self-renewal, proliferation, and differentiation properties. Stem cell therapy can aid by replacing the lost neurons, enhancing neurogenesis, and providing an enriched environment to the pre-existing neural cells. Stem cell therapy has provided us with promising results in regard to the animal AD models, and even pre-clinical studies have shown rather positive results. Cell replacement therapies are potential curative means to treat AD, and there are a number of undergoing human clinical trials to make Stem Cell therapy accessible for AD patients. In this review, we aim to discuss the AD pathophysiology and varied stem cell types and their application.

Cholinergic therapy in Alzheimer disease

This chapter describes how the clinical efficacy of orally administered cholinesterase inhibitors has been demonstrated through placebo-controlled randomized clinical trials leading to regulatory approval worldwide for the symptomatic treatment of Alzheimer disease. Over time, other clinical indications have been found, such as Dementia with Lewy Bodies and Parkinson disease Dementia. The route of administration includes transdermal patches. Side effects predominantly arise from peripheral parasympathetic stimulation. There is hope that drugs acting on acetylcholine release or on muscarinic receptors can exert additional symptomatic benefits.

Novel techniques for early diagnosis and monitoring of Alzheimer's disease

INTRODUCTION

Alzheimer's disease (AD) is the most common neurodegenerative disorder, which is characterized by a progressive loss of cognitive functions. The high prevalence, chronicity, and multimorbidity are very common in AD, which significantly impair the quality of life and functioning of patients. Early detection and accurate diagnosis of Alzheimer's disease (AD) can stop the illness from progressing thereby postponing its symptoms. Therefore, for the early diagnosis and monitoring of AD, more sensitive, noninvasive, straightforward, and affordable screening tools are needed.

AREAS COVERED

This review summarizes the importance of early detection methods and novel techniques for Alzheimer's disease diagnosis that can be used by healthcare professionals.

EXPERT OPINION

Early diagnosis assists the patient and caregivers to understand the problem establishing reasonable goals and making future plans together. Early diagnosis techniques not only help in monitoring disease progression but also provide crucial information for the development of novel therapeutic targets. Researchers can plan to potentially alleviate symptoms or slow down the progression of Alzheimer's disease by identifying early molecular changes and targeting altered pathways.

Evidence Following Conditional NICE Technology Appraisal Recommendations: A Critical Analysis of Methods, Quality and Risk of Bias

BACKGROUND

The National Institute for Health and Care Excellence (NICE) may approve health technologies on condition of more evidence generated only in research (OiR) or only with research (OwR). NICE specifies the information needed to comply with its request, although it may not necessarily guarantee good quality and timely evidence for re-appraisal, before reaching a final decision.

AIM

This study aimed to critically appraise the methods, quality and risk of bias of evidence generated in response to NICE OiR and OwR technology appraisal (TA) and highly specialised technologies (HSTs) recommendations.

METHODS

NICE TAs (between March 2000 and September 2020) and HST evaluations (to October 2023) of medicines were reviewed. Conditional recommendations were analysed to identify the evidence requested by NICE for re-appraisal. The new evidence was analysed for compliance with NICE's request and assessed using the Cochrane Collaboration's tools for risk of bias in randomised trials and the ROBINS-I tool for non-randomised evidence.

RESULTS

NICE made 54 conditional recommendations from TAs (13 OiR and 41 OwR) and five conditional recommendations for HSTs (all OwR). Of these, 16 TAs presented additional evidence for re-appraisal (9 OiR [69%] and 7 OwR [17%]) and three HSTs (3 OwR [60%]). Two of the nine re-appraised TAs with OiR recommendation and four of the seven OwR complied fully with NICE's request for further evidence, while all three from the HSTs complied. The majority of re-appraised TAs and HSTs included evidence that was deemed to be at serious, high, moderate or unclear risk of bias. Among the 26 randomised controlled trials from TAs assessed, eight were categorised as having low risk of bias in all domains and ten had at least one domain as a high risk of bias. Reporting was unclear for the remainder. Twenty-two non-randomised studies, primarily single-arm studies, were susceptible to biases mostly due to the selection of participants and to confounding. Two HSTs provided evidence from randomised controlled trials which were classified as unclear or high risk of bias. All non-randomised evidence from HSTs were categorised as moderate or serious risk of bias.

CONCLUSIONS

There is widespread non-compliance with agreed data requests and important variation in the quality of evidence submitted in response to NICE conditional approval recommendations. Quality standards ought to be stipulated in respect to evidence contributing to re-appraisals following NICE conditional approval recommendations.

Treatment of Alzheimer Disease

OBJECTIVE

Symptom-oriented treatment has been the mainstay of Alzheimer disease (AD) pharmacotherapy for decades. This article reviews the evidence basis for symptomatic treatments for AD and the emerging data on amyloid-lowering therapies with possible disease-slowing effects.

LATEST DEVELOPMENT

Amyloid-lowering monoclonal antibody therapies entered clinical use in 2021. In July 2023, lecanemab became the first of these to gain full US Food and Drug Administration (FDA) approval and limited Medicare payment coverage. Donanemab gained similar approval status in July 2024. The approved agents remove amyloid plaque from the brain and appear to slow clinical disease progression but can produce significant adverse events known as amyloid-related imaging abnormalities with cerebral edema or effusion and with cerebral hemorrhages. Extensive safety monitoring is therefore required, including scheduled MRI scans. Also in 2023, brexpiprazole became the first agent specifically approved by the FDA for agitation associated with AD. Suvorexant, an orexin receptor antagonist, previously was approved for the treatment of insomnia in people with mild and moderate AD.

ESSENTIAL POINTS

There is robust evidence for the use of acetylcholinesterase inhibitors for patients with mild, moderate, and severe dementia due to AD, including outcomes beyond changes in cognitive screening test scores. More limited studies support the use of memantine in moderate and severe stages. These agents have a primary effect of delaying decline in cognition and function and postponing the emergence of adverse behaviors. Pharmacotherapy for behavioral and psychological symptoms is less predictable, and most clinical trials have had negative results. Anti-amyloid therapies provide the first FDA-approved option to alter AD pathology, but an understanding of overall utility and value to patients remains in its infancy.

Galantamine-Memantine Combination in the Treatment of Parkinson's Disease Dementia

Parkinson's disease (PD) is a progressive neurodegenerative disorder that affects over 1% of population over age 60. It is defined by motor and nonmotor symptoms including a spectrum of cognitive impairments known as Parkinson's disease dementia (PDD). Currently, the only US Food and Drug Administration-approved treatment for PDD is rivastigmine, which inhibits acetylcholinesterase and butyrylcholinesterase increasing the level of acetylcholine in the brain. Due to its limited efficacy and side effect profile, rivastigmine is often not prescribed, leaving patients with no treatment options. PD has several derangements in neurotransmitter pathways (dopaminergic neurons in the nigrostriatal pathway, kynurenine pathway (KP), acetylcholine, α7 nicotinic receptor, and N-methyl-D-aspartate (NMDA) receptors) and rivastigmine is only partially effective as it only targets one pathway. Kynurenic acid (KYNA), a metabolite of tryptophan metabolism, affects the pathophysiology of PDD in multiple ways. Both galantamine (α7 nicotinic receptor) and memantine (antagonist of the NMDA subtype of the glutamate receptor) are KYNA modulators. When used in combination, they target multiple pathways. While randomized controlled trials (RCTs) with each drug alone for PD have failed, the combination of galantamine and memantine has demonstrated a synergistic effect on cognitive enhancement in animal models. It has therapeutic potential that has not been adequately assessed, warranting future randomized controlled trials. In this review, we summarize the KYNA-centric model for PD pathophysiology and discuss how this treatment combination is promising in improving cognitive function in patients with PDD through its action on KYNA.

Unlocking New Therapeutic Options for Vincristine-Induced Neuropathic Pain: The Impact of Preclinical Research

Vincristine, a vinca alkaloid, is used in chemotherapy protocols for cancers such as acute leukemia, Hodgkin's disease, neuroblastoma, cervical carcinoma, lymphomas, breast cancer, and melanoma. Among the common adverse effects of vincristine is peripheral neuropathy, with most patients receiving a cumulative dose over 4 mg/m2 who develop varying degrees of sensory neuropathy. The onset of vincristine-induced peripheral neuropathy can greatly affect patients' quality of life, often requiring dose adjustments or the discontinuation of treatment. Moreover, managing vincristine-induced peripheral neuropathy is challenging, with few effective therapeutic strategies available. In the past decade, preclinical studies have explored diverse substances aimed at preventing or alleviating VIPN. Our review consolidates these findings, focusing on the analgesic efficacy and potential mechanisms of various agents, including pharmaceutical drugs, natural compounds, and antioxidants, that show promise in reducing neuropathic pain and protecting neural integrity in preclinical models. Key novel therapeutic options, such as metabolic agents (liraglutide), enzyme inhibitors (ulinastatin), antipsychotics (aripiprazole), interleukin-1 receptor antagonists (anakinra), hormones (oxytocin), and antioxidants (thioctic acid), are highlighted for their neuroprotective, anti-inflammatory, and antioxidant effects. Through this synthesis, we aim to enhance the current understanding of VIPN management by identifying pharmacological strategies that target critical molecular pathways, laying the groundwork for future clinical studies. By clarifying these novel pharmacological approaches and elucidating their mechanisms of action, this review provides a foundation for developing more effective VIPN treatment strategies to ultimately improve patient outcomes.

Somatostatin: Linking Cognition and Alzheimer Disease to Therapeutic Targeting

Over 4 decades of research support the link between Alzheimer disease (AD) and somatostatin [somatotropin-releasing inhibitory factor (SRIF)]. SRIF and SRIF-expressing neurons play an essential role in brain function, modulating hippocampal activity and memory formation. Loss of SRIF and SRIF-expressing neurons in the brain rests at the center of a series of interdependent pathological events driven by amyloid-β peptide (Aβ), culminating in cognitive decline and dementia. The connection between the SRIF and AD further extends to the neuropsychiatric symptoms, seizure activity, and inflammation, whereas preclinical AD investigations show SRIF or SRIF receptor agonist administration capable of enhancing cognition. SRIF receptor subtype-4 activation in particular presents unique attributes, with the potential to mitigate learning and memory decline, reduce comorbid symptoms, and enhance enzymatic degradation of Aβ in the brain. Here, we review the links between SRIF and AD along with the therapeutic implications. SIGNIFICANCE STATEMENT: Somatostatin and somatostatin-expressing neurons in the brain are extensively involved in cognition. Loss of somatostatin and somatostatin-expressing neurons in Alzheimer disease rests at the center of a series of interdependent pathological events contributing to cognitive decline and dementia. Targeting somatostatin-mediated processes has significant therapeutic potential for the treatment of Alzheimer disease.

Altered Protein Palmitoylation as Disease Mechanism in Neurodegenerative Disorders

Palmitoylation, a lipid-based posttranslational protein modification, plays a crucial role in regulating various aspects of neuronal function through altering protein membrane-targeting, stabilities, and protein-protein interaction profiles. Disruption of palmitoylation has recently garnered attention as disease mechanism in neurodegeneration. Many proteins implicated in neurodegenerative diseases and associated neuronal dysfunction, including but not limited to amyloid precursor protein, β-secretase (BACE1), postsynaptic density protein 95, Fyn, synaptotagmin-11, mutant huntingtin, and mutant superoxide dismutase 1, undergo palmitoylation, and recent evidence suggests that altered palmitoylation contributes to the pathological characteristics of these proteins and associated disruption of cellular processes. In addition, dysfunction of enzymes that catalyze palmitoylation and depalmitoylation has been connected to the development of neurological disorders. This review highlights some of the latest advances in our understanding of palmitoylation regulation in neurodegenerative diseases and explores potential therapeutic implications.

What's in It for Me? Contextualizing the Potential Clinical Impacts of Lecanemab, Donanemab, and Other Anti-β-amyloid Monoclonal Antibodies in Early Alzheimer's Disease

A new era of disease-modifying therapy for Alzheimer's disease (AD) arrived in 2021 following the Food and Drug Administration's (FDA) decision to grant accelerated approval for aducanumab, an anti-β-amyloid (Aβ) monoclonal antibody designed to target Aβ aggregates, a biological component of AD. More recently, trial outcomes for lecanemab and donanemab, two additional antibodies of this drug class, have shown favorable and significant slowing of metrics for cognitive and functional decline. Lecanemab and donanemab have since received similar FDA approval to aducanumab in January 2023 and July 2024, respectively. Given that these therapies are a clearly emerging tool in the repertoire of clinicians treating AD and related dementias, a critical dialogue has been ongoing regarding the potential impacts and place for these therapies. Here, we seek to contextualize this debate by first considering factors involved in theoretically extrapolating current randomized control trial outcomes to estimate meaningful clinical impacts. In the process of this exercise, we outline a generally useful concept termed Summative Treatment-Associated Benefit measuring Long-term Efficacy/Effectiveness Area as a metric of summative benefits of treatment over the life course of an individual. Second, we consider current real-world factors, such as conditions of FDA approval and other points involved in clinical decision-making that will influence and/or temper the actual impacts of this drug class.

Approved drugs and natural products at clinical stages for treating Alzheimer's disease

Alzheimer's disease (AD) remains the foremost cause of dementia and represents a significant unmet healthcare need globally. The complex pathogenesis of AD, characterized by various pathological and physiological events, has historically challenged the development of anti-AD drugs. However, recent breakthroughs in AD drug development, including the approvals of aducanumab, lecanemab, and sodium oligomannate (GV-971), have ended a nearly two-decade hiatus in the introduction of new AD drugs. These developments have addressed long-standing challenges in AD drug development, marking a substantial shift in the therapeutic landscape of AD. Moreover, natural products (NPs) have shown promise in AD drug research, with several currently under clinical investigation. Their distinct properties and mechanisms of action offer new avenues to complement and enhance existing AD treatment approaches. This review article aims to provide an overview of the recent advancements and prospects in AD therapeutics, focusing on both NPs and approved drugs.

Alzheimer's Disease: Combination Therapies and Clinical Trials for Combination Therapy Development

Alzheimer's disease (AD) is a complex multifaceted disease. Recently approved anti-amyloid monoclonal antibodies slow disease progression by approximately 30%, and combination therapy appears necessary to prevent the onset of AD or produce greater slowing of cognitive and functional decline. Combination therapies may address core features, non-specific co-pathology commonly occurring in patients with AD (e.g., inflammation), or non-AD pathologies that may co-occur with AD (e.g., α-synuclein). Combination therapies may be advanced through co-development of more than one new molecular entity or through add-on strategies including an approved agent plus a new molecular entity. Addressing add-on combination therapy is currently urgent since patients on anti-amyloid monoclonal antibodies may be included in clinical trials for experimental agents. Phase 1 information must be generated for each agent in combination drug development. Phase 2 and Phase 3 of add-on therapies may contrast the new molecular entity, the approved agent as standard of care, and the combination. More complex development programs including standard or modified combinatorial designs are required for co-development of two or more new molecular entities. Biomarkers are markedly affected by anti-amyloid monoclonal antibodies, and these effects must be anticipated in add-on trials. Examining target engagement biomarkers and comparing the magnitude and sequence of biomarker changes in those receiving more than one therapy, compared with those on monotherapy, may be informative. Using network-based medicine approaches, computational strategies may identify rational combinations using disease and drug effect network mapping.

Impact of Apolipoprotein E Genotype on Neurocognitive Function in Patients With Brain Metastases: An Analysis of NRG Oncology's RTOG 0614

PURPOSE

Whole-brain radiation therapy (WBRT) is a common treatment for brain metastases and is frequently associated with decline in neurocognitive functioning (NCF). The e4 allele of the apolipoprotein E (APOE) gene is associated with increased risk of Alzheimer disease and NCF decline associated with a variety of neurologic diseases and insults. APOE carrier status has not been evaluated as a risk factor for onset time or extent of NCF impairment in patients with brain metastases treated with WBRT.

METHODS AND MATERIALS

NRG/Radiation Therapy Oncology Group 0614 treated adult patients with brain metastases with 37.5 Gy of WBRT (+/- memantine), performed longitudinal NCF testing, and included an optional blood draw for APOE analysis. NCF test results were compared at baseline and over time with mixed-effects models. A cause-specific Cox model for time to NCF failure was performed to assess the effects of treatment arm and APOE carrier status.

RESULTS

APOE results were available for 45% of patients (n = 227/508). NCF did not differ by APOE e4 carrier status at baseline. Mixed-effects modeling showed that APOE e4 carriers had worse memory after WBRT compared with APOE e4 noncarriers (Hopkins Verbal Learning Test-Revised total recall [least square mean difference, 0.63; P = .0074], delayed recognition [least square mean difference, 0.75; P = .023]). However, APOE e4 carrier status was not associated with time to NCF failure (hazard ratio, 0.86; 95% CI, 0.60-1.23; P = .40). Memantine delayed the time to NCF failure, regardless of carrier status (hazard ratio, 0.72; 95% CI, 0.52-1.01; P = .054).

CONCLUSIONS

APOE e4 carriers with brain metastases exhibited greater decline in learning and memory, executive function, and the Clinical Trial Battery Composite score after treatment with WBRT (+/- memantine), without acceleration of onset of difference in time to NCF failure.

Pro-cognitive effects of dual tacrine derivatives acting as cholinesterase inhibitors and NMDA receptor antagonists

Therapeutic options for Alzheimer's disease are limited. Dual compounds targeting two pathways concurrently may enable enhanced effect. The study focuses on tacrine derivatives inhibiting acetylcholinesterase (AChE) and simultaneously N-methyl-D-aspartate (NMDA) receptors. Compounds with balanced inhibitory potencies for the target proteins (K1578 and K1599) or increased potency for AChE (K1592 and K1594) were studied to identify the most promising pro-cognitive compound. Their effects were studied in cholinergic (scopolamine-induced) and glutamatergic (MK-801-induced) rat models of cognitive deficits in the Morris water maze. Moreover, the impacts on locomotion in the open field and AChE activity in relevant brain structures were investigated. The effect of the most promising compound on NMDA receptors was explored by in vitro electrophysiology. The cholinergic antagonist scopolamine induced a deficit in memory acquisition, however, it was unaffected by the compounds, and a deficit in reversal learning that was alleviated by K1578 and K1599. K1578 and K1599 significantly inhibited AChE in the striatum, potentially explaining the behavioral observations. The glutamatergic antagonist dizocilpine (MK-801) induced a deficit in memory acquisition, which was alleviated by K1599. K1599 also mitigated the MK-801-induced hyperlocomotion in the open field. In vitro patch-clamp corroborated the K1599-associated NMDA receptor inhibitory effect. K1599 emerged as the most promising compound, demonstrating pro-cognitive efficacy in both models, consistent with intended dual effect. We conclude that tacrine has the potential for development of derivatives with dual in vivo effects. Our findings contributed to the elucidation of the structural and functional properties of tacrine derivatives associated with optimal in vivo pro-cognitive efficacy.

Alzheimer's disease: part 2 - the present

Based on my work as a clinical neurologist with more than 50 years of experience in caring for patients with Alzheimer's disease (AD), I focus, in this review article, on the disease's two fundamental aspects for the doctor: diagnosis and treatment. The 1984 diagnostic criteria had been stable for more than a quarter of a century when it was replaced in 2011. Since then, there have been many discoveries, especially of biomarkers that have a heavy impact on the diagnosis of AD. Recently, AD biomarkers have become available in plasma, which certainly will cause a major change in the diagnosis of biological AD, a term that still needs care and information to society before being used in clinical practice. Three monoclonal antibodies against β-amyloid peptide have also been recently approved, and two of these have shown a small but statistically significant effect on clinical outcome. These monoclonal antibodies have had a greater effect on the reduction of amyloid plaques in the brain assessed by positron emission tomography (PET), and on the concentration of biomarkers in the cerebrospinal fluid (β-amyloid peptide with 42 amino acids and hyperphosphorylated tau protein) than in the neuropsychological and functional assessments. Even this small clinical effect will be encouraging for the development of new research, particularly helped by the greater ease of diagnosis and monitoring of the evolution of AD pathophysiology with plasma biomarkers. Recently, new diagnostic criteria for AD were presented by the Alzheimer's Association, causing controversy about their use in clinical practice.

Alzheimer's disease and its treatment-yesterday, today, and tomorrow

Alois Alzheimer described the first patient with Alzheimer's disease (AD) in 1907 and today AD is the most frequently diagnosed of dementias. AD is a multi-factorial neurodegenerative disorder with familial, life style and comorbidity influences impacting a global population of more than 47 million with a projected escalation by 2050 to exceed 130 million. In the USA the AD demographic encompasses approximately six million individuals, expected to increase to surpass 13 million by 2050, and the antecedent phase of AD, recognized as mild cognitive impairment (MCI), involves nearly 12 million individuals. The economic outlay for the management of AD and AD-related cognitive decline is estimated at approximately 355 billion USD. In addition, the intensifying prevalence of AD cases in countries with modest to intermediate income countries further enhances the urgency for more therapeutically and cost-effective treatments and for improving the quality of life for patients and their families. This narrative review evaluates the pathophysiological basis of AD with an initial focus on the therapeutic efficacy and limitations of the existing drugs that provide symptomatic relief: acetylcholinesterase inhibitors (AChEI) donepezil, galantamine, rivastigmine, and the N-methyl-D-aspartate receptor (NMDA) receptor allosteric modulator, memantine. The hypothesis that amyloid-β (Aβ) and tau are appropriate targets for drugs and have the potential to halt the progress of AD is critically analyzed with a particular focus on clinical trial data with anti-Aβ monoclonal antibodies (MABs), namely, aducanumab, lecanemab and donanemab. This review challenges the dogma that targeting Aβ will benefit the majority of subjects with AD that the anti-Aβ MABs are unlikely to be the "magic bullet". A comparison of the benefits and disadvantages of the different classes of drugs forms the basis for determining new directions for research and alternative drug targets that are undergoing pre-clinical and clinical assessments. In addition, we discuss and stress the importance of the treatment of the co-morbidities, including hypertension, diabetes, obesity and depression that are known to increase the risk of developing AD.

Caring for Individuals with Alzheimer's Disease: A Spotlight on Hispanic Caregivers

 A caregiver is a constantly evolving role that an individual most likely undertakes at some point in their lifetime. With discoveries and research in increasing life expectancy, the prevalence of neurological-related diseases, such as Alzheimer's disease (AD) and dementia, is certainly likely to require more caregivers. The demand for AD caregivers is escalating as the prevalence of the disease continues to rise. The projected rise in AD within the Hispanic population in the United States over the next few decades is expected to be the most significant among all ethnic groups. The Hispanic population faces unique dementia risks due to cultural factors like language barriers, lower education, and limited healthcare access. Higher rates of conditions such as diabetes and cardiovascular disease further elevate dementia risk. Family dynamics and caregiving responsibilities also differ, affecting dementia management within Hispanic households. Addressing these distinct challenges requires culturally sensitive approaches to diagnosis, treatment, and support for Hispanic individuals and their family's facing dementia. With AD and other dementia becoming more prevalent, this article will attempt to expand upon the status of caregivers concerning their economic, health, and cultural statuses. We will attempt to focus on the Hispanic caregivers that live in Texas and more specifically, West Texas due to the lack of current literature that applies to this area of Texas. Lastly, we discuss the ramifications of a multitude of factors that affect caregivers in Texas and attempt to provide tools that can be readily available for Hispanics and others alike.

Drug Development for Alzheimer's and Parkinson's Disease: Where Do We Go Now?

Neurodegenerative diseases (NDs) are a set of progressive, chronic, and incurable diseases characterized by the gradual loss of neurons, culminating in the decline of cognitive and/or motor functions. Alzheimer's disease (AD) and Parkinson's disease (PD) are the most common NDs and represent an enormous burden both in terms of human suffering and economic cost. The available therapies for AD and PD only provide symptomatic and palliative relief for a limited period and are unable to modify the diseases' progression. Over the last decades, research efforts have been focused on developing new pharmacological treatments for these NDs. However, to date, no breakthrough treatment has been discovered. Hence, the development of disease-modifying drugs able to halt or reverse the progression of NDs remains an unmet clinical need. This review summarizes the major hallmarks of AD and PD and the drugs available for pharmacological treatment. It also sheds light on potential directions that can be pursued to develop new, disease-modifying drugs to treat AD and PD, describing as representative examples some advances in the development of drug candidates targeting oxidative stress and adenosine A2A receptors.

Could protein phosphatase 2A and glycogen synthase kinase-3 beta be targeted by natural compounds to ameliorate Alzheimer's pathologies?

Alzheimer's disease (AD) is a progressive neurological disorder that impairs memory and cognitive abilities, primarily in the elderly. The burden of AD extends beyond patients, impacting families and caregivers due to the patients' reliance on assistance for daily tasks. The main features of the pathogenesis of AD are beta-amyloid plaques and neurofibrillary tangles (NFTs), that strongly correlate with oxidative stress and inflammation. NFTs result from misfolded and hyperphosphorylated tau proteins. Various studies have focused on tau phosphorylation, indicating protein phosphatase 2A (PP2A) as the primary tau phosphatase and glycogen synthase kinase-3 beta (GSK-3β) as the leading tau kinase. Experimental evidence suggests that inhibition of PP2A and increased GSK-3β activity contribute to neuroinflammation, oxidative stress, and cognitive impairment. Hence, targeting PP2A and GSK-3β with pharmacological approaches shows promise in treating AD. The use of natural compounds in the drug development for AD have been extensively studied for their antioxidant, anti-inflammatory, anti-cholinesterase, and neuroprotective properties, demonstrating therapeutic advantages in neurological diseases. Alongside the development of PP2A activator and GSK-3β inhibitor drugs, natural compounds are likely to have neuroprotective effects by increasing PP2A activity and decreasing GSK-3β levels. Therefore, based on the preclinical and clinical studies, the potential of PP2A and GSK-3β as therapeutic targets of natural compounds are highlighted in this review.

Targeting N-Methyl-d-Aspartate Receptors in Neurodegenerative Diseases

N-methyl-d-aspartate receptors (NMDARs) are the main class of ionotropic receptors for the excitatory neurotransmitter glutamate. They play a crucial role in the permeability of Ca2+ ions and excitatory neurotransmission in the brain. Being heteromeric receptors, they are composed of several subunits, including two obligatory GluN1 subunits (eight splice variants) and regulatory GluN2 (GluN2A~D) or GluN3 (GluN3A~B) subunits. Widely distributed in the brain, they regulate other neurotransmission systems and are therefore involved in essential functions such as synaptic transmission, learning and memory, plasticity, and excitotoxicity. The present review will detail the structure, composition, and localization of NMDARs, their role and regulation at the glutamatergic synapse, and their impact on cognitive processes and in neurodegenerative diseases (Alzheimer's, Huntington's, and Parkinson's disease). The pharmacology of different NMDAR antagonists and their therapeutic potentialities will be presented. In particular, a focus will be given on fluoroethylnormemantine (FENM), an investigational drug with very promising development as a neuroprotective agent in Alzheimer's disease, in complement to its reported efficacy as a tomography radiotracer for NMDARs and an anxiolytic drug in post-traumatic stress disorder.

Anti-dementia drugs: what is the evidence in advanced stages?

Dementia is a major public health concern due to its increasing prevalence, substantial caregiver burden, and high financial costs. Currently, the anti-dementia drugs aim only at a symptomatic effect. The subject of prescribing these drugs in advanced stages is a matter of considerable debate, with different countries making distinct recommendations. In this review article, we analyzed the evidence regarding cognitive and functional outcomes, adverse events, health-related costs, and caregiver burden in patients with advanced Alzheimer disease (AD) and mixed dementia. We included 35 studies. Most studies are heterogeneous, focus exclusively on AD, and show small benefits in terms of cognitive and functional scales. The overall evidence seems to suggest a benefit in introducing or maintaining anti-dementia drugs in patients with advanced dementia, but clinical meaningfulness is difficult to ascertain. The issue of costs and caregiver burden is significantly underexplored in this field but also seems to favor treatment continuation, despite a reduced overall effect. The decision of introducing or withdrawing anti-dementia drugs in advanced stages of dementia should be individualized. Future studies with homogeneous designs and outcomes are warranted.

Memantine: Updating a rare success story in pro-cognitive therapeutics

The great potential for NMDA receptor modulators as druggable targets in neurodegenerative disorders has been met with limited success. Considered one of the rare exceptions, memantine has consistently demonstrated restorative and prophylactic properties in many AD models. In clinical trials memantine slows the decline in cognitive performance associated with AD. Here, we provide an overview of the basic properties including pharmacological targets, toxicology and cellular effects of memantine. Evidence demonstrating reductions in molecular, physiological and behavioural indices of AD-like impairments associated with memantine treatment are also discussed. This represents both an extension and homage to Dr. Chris Parson's considerable contributions to our fundamental understanding of a success story in the AD treatment landscape.

The effects of different acetylcholinesterase inhibitors on EEG patterns in patients with Alzheimer's disease: A systematic review

OBJECTIVE

Alzheimer's disease (AD) is a progressive neurodegenerative disorder and the most common type of dementia. The early diagnosis of AD is an important factor for the control of AD progression. Electroencephalography (EEG) can be used for early diagnosis of AD. Acetylcholinesterase inhibitors (AChEIs) are also used for the amelioration of AD symptoms. In this systematic review, we reviewed the effect of different AChEIs including donepezil, rivastigmine, tacrine, physostigmine, and galantamine on EEG patterns in patients with AD.

METHODS

PubMed electronic database was searched and 122 articles were found. After removal of unrelated articles, 24 articles were selected for the present study.

RESULTS

AChEIs can decrease beta, theta, and delta frequency bands in patients with AD. However, conflicting results were found for alpha band. Some studies have shown increased alpha frequency, while others have shown decreased alpha frequency following treatment with AChEIs. The only difference was the type of drug.

CONCLUSIONS

We found that studies reporting the decreased alpha frequency used donepezil and galantamine, while studies reporting the increased alpha frequency used rivastigmine and tacrine. It was suggested that future studies should focus on the effect of different AChEIs on EEG bands, especially alpha frequency in patients with AD, to compare their effects and find the reason for their different influence on EEG patterns. Also, differences between the effects of AChEIs on oligodendrocyte differentiation and myelination may be another important factor. This is the first article investigating the effect of different AChEIs on EEG patterns in patients with AD.

Recent Advances in the Treatment and Management of Alzheimer's Disease: A Precision Medicine Perspective

About 60% to 70% of people with dementia have Alzheimer's Disease (AD), a neurodegenerative illness. One reason for this disorder is the misfolding of naturally occurring proteins in the human brain, specifically β-amyloid (Aβ) and tau. Certain diagnostic imaging techniques, such as amyloid PET imaging, tau PET imaging, Magnetic Resonance Imaging (MRI), Computerized Tomography (CT), and others, can detect biomarkers in blood, plasma, and cerebral spinal fluids, like an increased level of β-amyloid, plaques, and tangles. In order to create new pharmacotherapeutics for Alzheimer's disease, researchers must have a thorough and detailed knowledge of amyloid beta misfolding and other related aspects. Donepezil, rivastigmine, galantamine, and other acetylcholinesterase inhibitors are among the medications now used to treat Alzheimer's disease. Another medication that can temporarily alleviate dementia symptoms is memantine, which blocks the N-methyl-D-aspartate (NMDA) receptor. However, it is not able to halt or reverse the progression of the disease. Medication now on the market can only halt its advancement, not reverse it. Interventions to alleviate behavioral and psychological symptoms, exhibit anti- neuroinflammation and anti-tau effects, induce neurotransmitter alteration and cognitive enhancement, and provide other targets have recently been developed. For some Alzheimer's patients, the FDA-approved monoclonal antibody, aducanumab, is an option; for others, phase 3 clinical studies are underway for drugs, like lecanemab and donanemab, which have demonstrated potential in eliminating amyloid protein. However, additional study is required to identify and address these limitations in order to reduce the likelihood of side effects and maximize the therapeutic efficacy.

[Experience of using the combined drug Mioreol in patients with Alzheimer's disease and mixed dementia]

OBJECTIVE

The aim of the study was to evaluate the clinical efficacy, safety, and tolerability of a fixed-dose combination of donepezil and memantine (Mioreol) in patients with Alzheimer's disease (AD) and AD with cerebrovascular pathology.

MATERIAL AND METHODS

497 patients with moderate to severe dementia, average age 75.4+6.81 years, received Mioreol (donepezil 10 mg+memantine 20 mg). Treatment efficacy was assessed using the MMSE, clock drawing, Sandoz Clinical Geriatric Scale, and Clinical Global Impressions after 3 months of therapy. All adverse events during treatment were recorded.

RESULTS

The transition to Mioreol was accompanied by a reliable improvement in cognitive functions, emotional-behavioral indicators and neuropsychiatric status in general.

CONCLUSIONS

Mioreol demonstrated clinical efficacy, safety and good tolerability in patients with AD and AD with cerebrovascular pathology with moderate to severe dementia syndrome.

A Review of the Common Neurodegenerative Disorders: Current Therapeutic Approaches and the Potential Role of Bioactive Peptides

Neurodegenerative disorders, which include Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), and amyotrophic lateral sclerosis (ALS), represent a significant and growing global health challenge. Current therapies predominantly focus on symptom management rather than altering disease progression. In this review, we discuss the major therapeutic strategies in practice for these disorders, highlighting their limitations. For AD, the mainstay treatments are cholinesterase inhibitors and N-methyl-D-aspartate (NMDA) receptor antagonists. For PD, dopamine replacement therapies, including levodopa, are commonly used. HD is managed primarily with symptomatic treatments, and reusable extends survival in ALS. However, none of these therapies halts or substantially slows the neurodegenerative process. In contrast, this review highlights emerging research into bioactive peptides as potential therapeutic agents. These naturally occurring or synthetically designed molecules can interact with specific cellular targets, potentially modulating disease processes. Preclinical studies suggest that bioactive peptides may mitigate oxidative stress, inflammation, and protein misfolding, which are common pathological features in neurodegenerative diseases. Clinical trials using bioactive peptides for neurodegeneration are limited but show promising initial results. For instance, hemiacetal, a γ-secretase inhibitor peptide, has shown potential in AD by reducing amyloid-beta production, though its development was discontinued due to side effects. Despite these advancements, many challenges remain, including identifying optimal peptides, confirming their mechanisms of action, and overcoming obstacles related to their delivery to the brain. Future research should prioritize the discovery and development of novel bioactive peptides and improve our understanding of their pharmacokinetics and pharmacodynamics. Ultimately, this approach may lead to more effective therapies for neurodegenerative disorders, moving beyond symptom management to potentially modify the course of these devastating diseases.

A Critical Review of Noninvasive Brain Stimulation Technologies in Alzheimer's Dementia and Primary Progressive Aphasia

Multiple pharmacologic agents now have been approved in the United States and other countries as treatment to slow disease and clinical progression for Alzheimer's disease. Given these treatments have not been proven to lessen the cognitive deficits already manifested in the Alzheimer's Clinical Syndrome (ACS), and none are aimed for another debilitating dementia syndrome identified as primary progressive aphasia (PPA), there is an urgent need for new, safe, tolerable, and efficacious treatments to mitigate the cognitive deficits experienced in ACS and PPA. Noninvasive brain stimulation has shown promise for enhancing cognitive functioning, and there has been interest in its potential therapeutic value in ACS and PPA. This review critically examines the evidence of five technologies in ACS and PPA: transcranial direct current stimulation (tDCS), transcranial alternating current stimulation (tACS), transcranial random noise stimulation (tRNS), repetitive transcranial magnetic stimulation (rTMS), and noninvasive vagus nerve stimulation (nVNS). Many randomized controlled trials of tDCS and rTMS report positive treatment effects on cognition in ACS and PPA that persist out to at least 8 weeks, whereas there are few trials for tACS and none for tRNS and nVNS. However, most positive trials did not identify clinically meaningful changes, underscoring that clinical efficacy has yet to be established in ACS and PPA. Much is still to be learned about noninvasive brain stimulation in ACS and PPA, and shifting the focus to prioritize clinical significance in addition to statistical significance in trials could yield greater success in understanding its potential cognitive effects and optimal parameters.

Combining donepezil and memantine via mannosylated PLGA nanoparticles for intranasal delivery: Characterization and preclinical studies

The current work is focused on developing mannose-coated PLGA nanoparticles for delivering Donepezil and Memantine in one dosage form. The formulated nanoparticles were prepared using a simple emulsification technique. The final coated NPs exhibited 179.4 nm size and - 33.1 mV zeta potential and spherical shape. The concentration of IN-administrated MEM and DPZ mannose coated NPs in brain was ~573 and 207 ng/mL respectively. This amount accounts for 3 times more in comparison to uncoated NPs administered via intranasal and peroral routes. The plasma concentration of coated NPs administered via the intranasal route was various times less in comparison to other groups. In the field of pharmacodynamics, the administration of coated NPs via the IN route has shown superior efficacy in comparison to other groups in various investigations involving neurobehavioral assessments, gene expression analyses and biochemical estimations. The findings indicate that the IN route may be a potential avenue for delivering therapeutic agents using nanoparticles to treat neurological illnesses. This approach shows promise as a viable alternative to traditional dose forms and administration methods.

Review of Phytochemical Potency as a Natural Anti-Helicobacter pylori and Neuroprotective Agent

Phytochemicals are plant secondary metabolites that show health benefits for humans due to their bioactivity. There is a huge variety of phytochemicals that have already been identified, and these compounds can act as antimicrobial and neuroprotection agents. Due to their anti-microbial activity and neuroprotection, several phytochemicals might have the potency to be used as natural therapeutic agents, especially for Helicobacter pylori infection and neurodegenerative disease, which have become a global health concern nowadays. According to previous research, there are some connections between H. pylori infection and neurodegenerative diseases, especially Alzheimer's disease. Hence, this comprehensive review examines different kinds of phytochemicals from natural sources as potential therapeutic agents to reduce H. pylori infection and improve neurodegenerative disease. An additional large-scale study is needed to establish the connection between H. pylori infection and neurodegenerative disease and how phytochemicals could improve this condition.

A blood-based, metabolite and demographic characteristic markers panel for the diagnosis of Alzheimer's disease

Aims: This work was designed to provide early diagnosis strategies for Alzheimer's disease (AD) based on the identification of blood metabolic biomarkers. Patients & methods: A total of 90 subjects aged 60 years or older were included in this study; 45 patients were assigned to the case group and control group, respectively. A total of 31 target metabolites were quantitatively analyzed by parallel reaction monitoring between the two groups. Results & conclusion: Three metabolites were screened out, including cystine, serine and alanine/sarcosine. Logistic regression and random forest analysis were used to establish AD diagnosis models, and the model combining metabolic biomarkers and demographic variables had higher detection efficiency (area under the curve = 0.869). A combination diagnostic model to provide a scientific reference for early screening and diagnosis of AD was constructed.

A causal inference study: The impact of the combined administration of Donepezil and Memantine on decreasing hospital and emergency department visits of Alzheimer's disease patients

Alzheimer's disease is the most common type of dementia that currently affects over 6.5 million people in the U.S. Currently there is no cure and the existing drug therapies attempt to delay the mental decline and improve cognitive abilities. Two of the most commonly prescribed such drugs are Donepezil and Memantine. We formally tested and confirmed the presence of a beneficial drug-drug interaction of Donepezil and Memantine using a causal inference analysis. We applied doubly robust estimators to one of the largest and high-quality medical databases to estimate the effect of two commonly prescribed Alzheimer's disease (AD) medications, Donepezil and Memantine, on the average number of hospital or emergency department visits per year among patients diagnosed with AD. Our results show that, compared to the absence of medication scenario, the Memantine monotherapy, and the Donepezil monotherapy, the combined use of Donepezil and Memantine treatment significantly reduces the average number of hospital or emergency department visits per year by 0.078 (13.8%), 0.144 (25.5%), and 0.132 days (23.4%), respectively. The assessed decline in the average number of hospital or emergency department visits per year is consequently associated with a substantial reduction in medical costs. As of 2022, according to the Alzheimer's Disease Association, there were over 6.5 million individuals aged 65 and older living with AD in the US alone. If patients who are currently on no drug treatment or using either Donepezil or Memantine alone were switched to the combined used of Donepezil and Memantine therapy, the average number of hospital or emergency department visits could decrease by over 613 thousand visits per year. This, in turn, would lead to a remarkable reduction in medical expenses associated with hospitalization of AD patients in the US, totaling over 940 million dollars per year.

Emerging Symptomatic Treatment of Chronic Traumatic Encephalopathy (CTE): a narrative review

INTRODUCTION

Chronic traumatic encephalopathy (CTE) is an emergent neurodegenerative tauopathy well characterized pathologically but with limited consensus about clinical criteria. The clinical features include cognitive, behavioral, and motor symptoms such as parkinsonism, gait, balance disorder, and bulbar impairment. Their recognition derives from retrospective studies in pathologically confirmed CTE patients. This is one of the main reasons for the lack of specific pharmacological studies targeting symptoms or pathologic pathways of this disease.

AREAS COVERED

In this narrative review, we overview the possible symptomatic treatment options for CTE, based on pathological similarities with other neurodegenerative diseases that may share common pathological pathways with CTE. The PubMed database was screened for articles addressing the symptomatic treatment of CTE and Traumatic Encephalopathy Syndrome (TES). Additional references were retrieved by reference cross-check and retained if pertinent to the subject. The clinicaltrials.gov database was screened for ongoing trials on the treatment of CTE.

EXPERT OPINION

The similarities with the other tauopathies allow us, in the absence of disease-specific evidence, to translate some knowledge from these neurodegenerative disorders to CTE's symptomatic treatment, but any conclusion should be drawn cautiously and a patient-tailored strategy should be always preferred balancing the risks and benefits of each treatment.

A Multicentre, Randomised, Open-Label, Prospective Study to Estimate the Add-On Effects Of Memantine as Ebixa® Oral Pump (Solution) on Language in Patients with Moderate to Severe Alzheimer's Disease Already Receiving Donepezil (ROMEO-AD)

INTRODUCTION

This multicentre, randomised, open-label, and prospective study aimed to evaluate the effectiveness of memantine (memantine solution) on speech function in patients with moderate to severe Alzheimer's disease (AD) who were already on donepezil therapy.

METHODS

Participants were divided into two groups: the drug trial group was administered donepezil + memantine (memantine solution), while the control group was administered only donepezil. Patients in the test group were required to increase the dose of memantine by 5 mg/day per week for the first 4 weeks and were maintained at 20 mg/day until the end of the trial.

RESULTS

Of the 188 participants, 24 dropped out, and 164 completed the final research process. As the primary outcome, K-WAB showed an increase in scores in both groups compared to baseline scores; however, the difference was not statistically significant (P = 0.678). After 12 weeks, the donepezil treatment group had higher K-MMSE and lower CDR-SB scores than the donepezil and memantine combination group, indicating better cognitive and functional status. However, this effect was not sustained for 24 weeks. Patients who were assigned to receive only donepezil had Relevant Outcome Scale for AD (ROSA) scores that were higher by an average of 4.6 points compared to the donepezil and memantine combination group. The NPI-Q index improved compared to baseline values in both groups.

CONCLUSIONS

Although several clinical studies have reported significant improvements in speech function after the administration of memantine, clinical studies on speech function improvement in patients with Alzheimer's disease are still insignificant. There are no studies on the effect of donepezil and memantine in combination treatment on language function in the moderate and severe stages of AD. Therefore, we investigated the effect of memantine (memantine solution) on speech function in patients with moderate to severe AD who were administered donepezil at a stable dose. Although the efficacy of the combination therapy was not superior to that of donepezil monotherapy alone, memantine was effective in improving behavioural symptoms in patients with moderate or severe AD.

The Disruption of NMDAR/TRPM4 Death Signaling with TwinF Interface Inhibitors: A New Pharmacological Principle for Neuroprotection

With the discovery that the acquisition of toxic features by extrasynaptic NMDA receptors (NMDARs) involves their physical interaction with the non-selective cation channel, TRPM4, it has become possible to develop a new pharmacological principle for neuroprotection, namely the disruption of the NMDAR/TRPM4 death signaling complex. This can be accomplished through the expression of the TwinF domain, a 57-amino-acid-long stretch of TRPM4 that mediates its interaction with NMDARs, but also using small molecule TwinF interface (TI) inhibitors, also known as NMDAR/TRPM4 interaction interface inhibitors. Both TwinF and small molecule TI inhibitors detoxify extrasynaptic NMDARs without interfering with synaptic NMDARs, which serve important physiological functions in the brain. As the toxic signaling of extrasynaptic NMDARs contributes to a wide range of neurodegenerative conditions, TI inhibitors may offer therapeutic options for currently untreatable human neurodegenerative diseases including Amyotrophic Lateral Sclerosis, Alzheimer's disease, and Huntington's disease.

A Systematic Review of Pharmacological Interventions for Apathy in Aging Neurocognitive Disorders

OBJECTIVE

Apathy, a frequent neuropsychiatric symptom in aging neurocognitive disorders, has been associated with cognitive decline and functional disability. Therefore, timely provision of pharmacological interventions for apathy is greatly needed.

DESIGN

A systematical literature review of existing studies was conducted up to 30 May 2023 in several databases (PubMed, PsychInfo, Cochrane, Google Scholar, etc.) that included randomized controlled trials (RCTs) and meta-analyses assessing pharmacological treatments for apathy in aging neurocognitive disorders. The quality of the studies was appraised.

RESULTS

In patients with Alzheimer's Disease (AD), donepezil, galantamine, rivastigmine, methylphenidate, and gingko biloba were proven efficacious for apathy, while rivastigmine, cognitive enhancer IRL752 and piribedil were found to be beneficial in patients with Parkinson's Disease (PD) and agomelatine in patients with Frontotemporal Dementia (FD). The extensive proportion of RCTs in which apathy was used as a secondary outcome measure, along with the considerable methodological heterogeneity, did not allow the evaluation of group effects.

CONCLUSIONS

Pharmacological interventions for apathy in aging neurocognitive disorders are complex and under-investigated. The continuation of systematic research efforts and the provision of individualized treatment for patients suffering from these disorders is vital.

Cognitive reserve and individual differences in brain tumour patients

The aim of the paper is to determine the effects of the cognitive reserve on brain tumour patients' cognitive functions and, specifically, if cognitive reserve helps patients cope with the negative effects of brain tumours on their cognitive functions. We retrospectively studied a large sample of around 700 patients, diagnosed with a brain tumour. Each received an MRI brain examination and performed a battery of tests measuring their cognitive abilities before they underwent neurosurgery. To account for the complexity of cognitive reserve, we construct our cognitive reserve proxy by combining three predictors of patients' cognitive performance, namely, patients' education, occupation, and the environment where they live. Our statistical analysis controls for the type, side, site, and size of the lesion, for fluid intelligence quotient, and for age and gender, in order to tease out the effect of cognitive reserve on each of these tests. Clinical neurological variables have the expected effects on cognitive functions. We find a robust positive effect of cognitive reserve on patients' cognitive performance. Moreover, we find that cognitive reserve modulates the effects of the volume of the lesion: the additional negative impact of an increase in the tumour size on patients' performance is less severe for patients with higher cognitive reserve. We also find substantial differences in these effects depending on the cerebral hemisphere where the lesion occurred and on the cognitive function considered. For several of these functions, the positive effect of cognitive reserve is stronger for patients with lesions in the left hemisphere than for patients whose lesions are in the right hemisphere. The development of prevention strategies and personalized rehabilitation interventions will benefit from our contribution to understanding the role of cognitive reserve, in addition to that of neurological variables, as one of the factors determining the patients' individual differences in cognitive performance caused by brain tumours.

ARCH: Large-scale Knowledge Graph via Aggregated Narrative Codified Health Records Analysis

Objective

Electronic health record (EHR) systems contain a wealth of clinical data stored as both codified data and free-text narrative notes, covering hundreds of thousands of clinical concepts available for research and clinical care. The complex, massive, heterogeneous, and noisy nature of EHR data imposes significant challenges for feature representation, information extraction, and uncertainty quantification. To address these challenges, we proposed an efficient Aggregated naRrative Codified Health (ARCH) records analysis to generate a large-scale knowledge graph (KG) for a comprehensive set of EHR codified and narrative features.

Methods

The ARCH algorithm first derives embedding vectors from a co-occurrence matrix of all EHR concepts and then generates cosine similarities along with associated p -values to measure the strength of relatedness between clinical features with statistical certainty quantification. In the final step, ARCH performs a sparse embedding regression to remove indirect linkage between entity pairs. We validated the clinical utility of the ARCH knowledge graph, generated from 12.5 million patients in the Veterans Affairs (VA) healthcare system, through downstream tasks including detecting known relationships between entity pairs, predicting drug side effects, disease phenotyping, as well as sub-typing Alzheimer's disease patients.

Results

ARCH produces high-quality clinical embeddings and KG for over 60,000 EHR concepts, as visualized in the R-shiny powered web-API (https://celehs.hms.harvard.edu/ARCH/). The ARCH embeddings attained an average area under the ROC curve (AUC) of 0.926 and 0.861 for detecting pairs of similar EHR concepts when the concepts are mapped to codified data and to NLP data; and 0.810 (codified) and 0.843 (NLP) for detecting related pairs. Based on the p -values computed by ARCH, the sensitivity of detecting similar and related entity pairs are 0.906 and 0.888 under false discovery rate (FDR) control of 5%. For detecting drug side effects, the cosine similarity based on the ARCH semantic representations achieved an AUC of 0.723 while the AUC improved to 0.826 after few-shot training via minimizing the loss function on the training data set. Incorporating NLP data substantially improved the ability to detect side effects in the EHR. For example, based on unsupervised ARCH embeddings, the power of detecting drug-side effects pairs when using codified data only was 0.15, much lower than the power of 0.51 when using both codified and NLP concepts. Compared to existing large-scale representation learning methods including PubmedBERT, BioBERT and SAPBERT, ARCH attains the most robust performance and substantially higher accuracy in detecting these relationships. Incorporating ARCH selected features in weakly supervised phenotyping algorithms can improve the robustness of algorithm performance, especially for diseases that benefit from NLP features as supporting evidence. For example, the phenotyping algorithm for depression attained an AUC of 0.927 when using ARCH selected features but only 0.857 when using codified features selected via the KESER network[1]. In addition, embeddings and knowledge graphs generated from the ARCH network were able to cluster AD patients into two subgroups, where the fast progression subgroup had a much higher mortality rate.

Conclusions

The proposed ARCH algorithm generates large-scale high-quality semantic representations and knowledge graph for both codified and NLP EHR features, useful for a wide range of predictive modeling tasks.