Frontotemporal dementia: latest evidence and clinical implications

Validating the nutraceutical and neuroprotective pharmacodynamics of flavones

Neurodegenerative disorders are generally characterized by progressive neuronal loss and cognitive decline, with underlying mechanisms involving oxidative stress, protein aggregation, neuroinflammation, and synaptic dysfunction. Currently, the available treatment options only improve the symptoms of the disease but do not stop disease progression; neurodegeneration. This underscores the urgent need for novel therapeutic strategies targeting multiple neurodegenerative pathways alongside the conventional therapeutic strategies available. Emerging evidence demonstrates that flavones a subgroup of flavonoids found abundantly in various dietary sources, have surfaced as promising candidates for neuroprotection due to their multifaceted pharmacological properties. Flavones possess the potency to modulate these pathophysiological processes through their antioxidant, anti-inflammatory, and neurotrophic activities. Additionally, flavones have been shown to interact with various cellular targets, including receptors and enzymes, to confer neuroprotection. Though there are ample evidence available, the nutraceutical and neuroprotective pharmacodynamics of flavones have not been very well established. Hence, the current review aims to explores the therapeutic potential of flavones as nutraceuticals with neuroprotective effects, focusing on their ability to modulate key pathways implicated in neurodegenerative diseases. The current article also aims to actuate supplementary research into flavones as potential agents for alleviating neurodegeneration and improving patient outcomes in neurodegenerative disorders globally.

Dementia: Common Syndromes and Modifiable Risk and Protective Factors

Dementia is an umbrella term for multiple conditions that lead to progressive cognitive decline and impaired activities of daily living. Neuropsychological evaluation is essential for characterizing the distinct cognitive and behavioral profile that can aid in the diagnostic process and treatment planning for dementia. Modifiable risk factors for dementia such as nutrition, physical activity, sleep, cognitive and social engagement, and stress provide important avenues for prevention. Neurologists and other health care providers can help patients reduce their risk for dementia by providing them with education about modifiable factors and connecting them to resources to empower them to engage in brain-healthy behavior.

Pharmacotherapy for behavioural manifestations in frontotemporal dementia: An expert consensus from the European Reference Network for Rare Neurological Diseases (ERN-RND)

BACKGROUND AND PURPOSE

Frontotemporal dementia (FTD) is a neurodegenerative disorder characterized by pervasive personality and behavioural disturbances with severe impact on patients and caregivers. In current clinical practice, treatment is based on nonpharmacological and pharmacological approaches. Unfortunately, trial-based evidence supporting symptomatic pharmacological treatment for the behavioural disturbances in FTD is scarce despite the significant burden this poses on the patients and caregivers.

METHOD

The study examined drug management decisions for several behavioural disturbances in patients with FTD by 21 experts across European expert centres affiliated with the European Reference Network for Rare Neurological Diseases (ERN-RND).

RESULTS

The study revealed the highest consensus on drug treatments for physical and verbal aggression, impulsivity and obsessive delusions. Antipsychotics (primarily quetiapine) were recommended for behaviours posing safety risks to both patients and caregivers (aggression, self-injury and self-harm) and nightly unrest. Selective serotonin reuptake inhibitors were recommended for perseverative somatic complaints, rigidity of thought, hyperphagia, loss of empathy and for impulsivity. Trazodone was specifically recommended for motor unrest, mirtazapine for nightly unrest, and bupropion and methylphenidate for apathy. Additionally, bupropion was strongly advised against in 10 out of the 14 behavioural symptoms, emphasizing a clear recommendation against its use in the majority of cases.

CONCLUSIONS

The survey data can provide expert guidance that is helpful for healthcare professionals involved in the treatment of behavioural symptoms. Additionally, they offer insights that may inform prioritization and design of therapeutic studies, particularly for existing drugs targeting behavioural disturbances in FTD.

Cross-disorder and disease-specific pathways in dementia revealed by single-cell genomics

The development of successful therapeutics for dementias requires an understanding of their shared and distinct molecular features in the human brain. We performed single-nuclear RNA-seq and ATAC-seq in Alzheimer's disease (AD), frontotemporal dementia (FTD), and progressive supranuclear palsy (PSP), analyzing 41 participants and ∼1 million cells (RNA + ATAC) from three brain regions varying in vulnerability and pathological burden. We identify 32 shared, disease-associated cell types and 14 that are disease specific. Disease-specific cell states represent glial-immune mechanisms and selective neuronal vulnerability impacting layer 5 intratelencephalic neurons in AD, layer 2/3 intratelencephalic neurons in FTD, and layer 5/6 near-projection neurons in PSP. We identify disease-associated gene regulatory networks and cells impacted by causal genetic risk, which differ by disorder. These data illustrate the heterogeneous spectrum of glial and neuronal compositional and gene expression alterations in different dementias and identify therapeutic targets by revealing shared and disease-specific cell states.

The Effect of Dipeptide Repeat Proteins on FUS/TDP43-RNA Condensation in C9orf72 ALS/FTD

Condensation of RNA binding proteins (RBPs) with RNA is essential for cellular function. The most common familial cause of the diseases ALS and FTD is C9orf72 repeat expansion disorders that produce dipeptide repeat proteins (DPRs). We explore the hypothesis that DPRs disrupt the native condensation behavior of RBPs and RNA through molecular interactions resulting in toxicity. FUS and TDP43 are two RBPs known to be affected in ALS/FTD. We use our previously developed 1-bead-per-amino acid and a newly developed 3-bead-per-nucleotide molecular dynamics model to explore ternary phase diagrams of FUS/TDP43-RNA-DPR systems. We show that the most toxic arginine containing DPRs (R-DPRs) can disrupt the RBP condensates through cation-π interactions and can strongly sequester RNA through electrostatic interactions. The native droplet morphologies are already modified at small additions of R-DPRs leading to non-native FUS/TDP43-encapsulated condensates with a marbled RNA/DPR core.

Single-domain magnetic particles with motion behavior under electromagnetic AC and DC fields are a fatal cargo in Metropolitan Mexico City pediatric and young adult early Alzheimer, Parkinson, frontotemporal lobar degeneration and amyotrophic lateral sclerosis and in ALS patients

Metropolitan Mexico City (MMC) children and young adults exhibit overlapping Alzheimer and Parkinsons' diseases (AD, PD) and TAR DNA-binding protein 43 pathology with magnetic ultrafine particulate matter (UFPM) and industrial nanoparticles (NPs). We studied magnetophoresis, electron microscopy and energy-dispersive X-ray spectrometry in 203 brain samples from 14 children, 27 adults, and 27 ALS cases/controls. Saturation isothermal remanent magnetization (SIRM), capturing magnetically unstable FeNPs ~ 20nm, was higher in caudate, thalamus, hippocampus, putamen, and motor regions with subcortical vs. cortical higher SIRM in MMC ≤ 40y. Motion behavior was associated with magnetic exposures 25-100 mT and children exhibited IRM saturated curves at 50-300 mT associated to change in NPs position and/or orientation in situ. Targeted magnetic profiles moving under AC/AD magnetic fields could distinguish ALS vs. controls. Motor neuron magnetic NPs accumulation potentially interferes with action potentials, ion channels, nuclear pores and enhances the membrane insertion process when coated with lipopolysaccharides. TEM and EDX showed 7-20 nm NP Fe, Ti, Co, Ni, V, Hg, W, Al, Zn, Ag, Si, S, Br, Ce, La, and Pr in abnormal neural and vascular organelles. Brain accumulation of magnetic unstable particles start in childhood and cytotoxic, hyperthermia, free radical formation, and NPs motion associated to 30-50 μT (DC magnetic fields) are critical given ubiquitous electric and magnetic fields exposures could induce motion behavior and neural damage. Magnetic UFPM/NPs are a fatal brain cargo in children's brains, and a preventable AD, PD, FTLD, ALS environmental threat. Billions of people are at risk. We are clearly poisoning ourselves.

Shedding light on subiculum's role in human brain disorders

Subiculum is a pivotal output component of the hippocampal formation, a structure often overlooked in neuroscientific research. Here, this review aims to explore the role of the subiculum in various brain disorders, shedding light on its significance within the functional-neuroanatomical perspective on neurological diseases. The subiculum's involvement in multiple brain disorders was thoroughly examined. In Alzheimer's disease, subiculum alterations precede cognitive decline, while in epilepsy, the subiculum plays a critical role in seizure initiation. Stress involves the subiculum's impact on the hypothalamic-pituitary-adrenocortical axis. Moreover, the subiculum exhibits structural and functional changes in anxiety, schizophrenia, and Parkinson's disease, contributing to cognitive deficits. Bipolar disorder is linked to subiculum structural abnormalities, while autism spectrum disorder reveals an alteration of inward deformation in the subiculum. Lastly, frontotemporal dementia shows volumetric differences in the subiculum, emphasizing its contribution to the disorder's complexity. Taken together, this review consolidates existing knowledge on the subiculum's role in brain disorders, and may facilitate future research, diagnostic strategies, and therapeutic interventions for various neurological conditions.

Association of Open-Angle Glaucoma With Dementia in California Medicare Beneficiaries

PURPOSE

To examine the associations between open-angle glaucoma (OAG) subtypes and dementia in 2019 California Medicare beneficiaries.

DESIGN

Retrospective cross-sectional study.

METHODS

OAG diagnosis was determined by the International Classification of Diseases, Tenth Revision (ICD-10), diagnosis codes in part B claims, including the following OAG subtypes: primary open-angle glaucoma (POAG), normal tension glaucoma (NTG), pseudoexfoliative glaucoma (PXG), and pigmentary glaucoma (PG). Diagnoses of any dementia, Alzheimer dementia (AD), frontotemporal dementia (FTD), Lewy body dementia (LBD), and vascular dementia (VD) were identified by ICD-10 diagnosis codes. Covariates included demographics, systemic diseases, depression, hearing loss, obesity, smoking and alcohol-related disorders, and long-term aspirin, anticoagulant, and antithrombotic or antiplatelet use. Univariate and multivariable logistic regression models were used to assess the associations between OAG and dementia, adjusting for all covariates. Age-stratified analysis was also performed for beneficiaries aged 65-74 years, 75-84 years, and ≥85 years.

RESULTS

Among the 2,431,150 California Medicare beneficiaries included in this study, 104,873 (4.3%) had POAG, 9199 (0.4%) had NTG, 4045 (0.2%) had PXG, and 1267 (0.05%) had PG. The overall prevalence of any dementia was 3.2% (n = 79,009). In adjusted analyses, the odds of any dementia were lower for beneficiaries with all OAG subtypes compared with beneficiaries without glaucoma (odds ratio [OR] = 0.74 for POAG, OR = 0.74 for PXG, OR = 0.60 for NTG, and OR = 0.38 for PG; P < .01). In age-stratified analyses, beneficiaries with PXG had greater odds of VD (OR 2.84, P = .006; aOR 2.18, P = .04) in the youngest age stratum (65-74 years) compared to patients with no glaucoma. The odds for any dementia were lower for beneficiaries with all OAG subtypes compared to beneficiaries without glaucoma in the oldest, but not in the youngest, age stratum.

CONCLUSIONS

In the 2019 California Medicare population, PXG is associated with an increased likelihood of VD in beneficiaries 65-74 years old, whereas other subtypes of POAG are associated with a decreased likelihood of any dementia. These findings may suggest selection bias because older adults who continue to follow up with glaucoma care may be more cognitively intact. Further studies are needed to better understand the complex relationship between glaucoma, dementia, and their subtypes.

Research trends and hotspots for frontotemporal dementia from 2000 to 2022: a bibliometric analysis

Background

Frontotemporal dementia (FTD) is a neurodegenerative disease with clinical, pathological, and genetic heterogeneity. FTD is receiving increasing attention because it is the second leading cause of early-onset dementia after Alzheimer's disease. This study aimed to analyse the research trends and hotspots of FTD from 2000 to 2022 using bibliometrics.

Methods

Papers related to FTD from 2000 to 2020 were systematically searched through the Web of Science Core Collection (WOSCC). Citespace and Vosviewer software were used to visually analyse the retrieved data of countries/regions, institutions, journals, authors, references, and keywords. Microsoft Excel was used to generate the annual publications and growth trends.

Results

There were 10,227 papers included in the bibliometric analysis. The annual publication output on FTD has increased significantly from 2000 to 2022, with papers published in 934 academic journals and 87 countries/regions. The Journal of Alzheimer's Disease was the most popular, with 488 papers about FTD. The most productive countries/regions, institutions, and authors are the United States (n = 4,037), the University of California San Francisco (n = 687), and Miller, Bruce L. (n = 427), respectively. The article by Katya Rascovsky and her colleagues published on Brain in 2011 was the most cocited paper, with 625 citations. The research hotspots in this field were the clinical diagnostic criteria, subdivision, and pathological mechanism of FTD, such as tau protein, chromosome 17, progranulin, TDP-43, and C9orf72.

Conclusion

The future research direction is based on biomarkers and pathological mechanisms to diagnose and differential diagnose FTD from the aspects of behavior, neuropathology, neuroimaging, and serum markers.

Free Will as Defined by the Constrained Disorder Principle: a Restricted, Mandatory, Personalized, Regulated Process for Decision-Making

The concept of free will has challenged physicists, biologists, philosophers, and other professionals for decades. The constrained disorder principle (CDP) is a fundamental law that defines systems according to their inherent variability. It provides mechanisms for adapting to dynamic environments. This work examines the CDP's perspective of free will concerning various free will theories. Per the CDP, systems lack intentions, and the "freedom" to select and act is built into their design. The "freedom" is embedded within the response range determined by the boundaries of the systems' variability. This built-in and self-generating mechanism enables systems to cope with perturbations. According to the CDP, neither dualism nor an unknown metaphysical apparatus dictates choices. Brain variability facilitates cognitive adaptation to complex, unpredictable situations across various environments. Human behaviors and decisions reflect an underlying physical variability in the brain and other organs for dealing with unpredictable noises. Choices are not predetermined but reflect the ongoing adaptation processes to dynamic prssu½res. Malfunctions and disease states are characterized by inappropriate variability, reflecting an inability to respond adequately to perturbations. Incorporating CDP-based interventions can overcome malfunctions and disease states and improve decision processes. CDP-based second-generation artificial intelligence platforms improve interventions and are being evaluated to augment personal development, wellness, and health.

Genetic variability of FOXP2 and its targets CNTNAP2 and PRNP in frontotemporal dementia: A pilot study in a southern Italian population

The Forkhead box P2 (FOXP2) is an evolutionary conserved transcription factor involved in the maintenance of neuronal networks, implicated in language disorders. Some evidence suggests a possible link between FOXP2 genetic variability and frontotemporal dementia (FTD) pathology and related endophenotypes. To shed light on this issue, we analysed the association between single-nucleotide polymorphisms (SNPs) in FOXP2 and FTD in 113 patients and 223 healthy controls. In addition, we investigated SNPs in two putative targets of FOXP2, CNTNAP2, Contactin-associated protein-like 2 and PRNP, prion protein genes. Overall, 27 SNPs were selected by a tagging approach. FOXP2-rs17213159-C/T resulted associated with disease risk (OR = 2.16, P = 0.0004), as well as with age at onset and severity of dementia. Other FOXP2 markers were associated with semantic and phonological fluency scores, cognitive levels (MMSE) and neuropsychological tests. Associations with language, cognitive and brain atrophy measures were found with CNTNAP2 and PRNP genetic variability. Overall, although preliminary, results here presented suggest an influence of regulatory pathways centred on FOXP2 as a molecular background of FTD affecting neurological function of multiple brain areas.

Exploring the Comprehensive Neuroprotective and Anticancer Potential of Afzelin

Neurodegenerative diseases (Alzheimer's disease, Parkinson's disease, Huntington's disease, and others) and cancer, seemingly disparate in their etiology and manifestation, exhibit intriguing associations in certain cellular and molecular processes. Both cancer and neurodegenerative diseases involve the deregulation of cellular processes such as apoptosis, proliferation, and DNA repair and pose a significant global health challenge. Afzelin (kaempferol 3-O-rhamnoside) is a flavonoid compound abundant in various plant sources. Afzelin exhibits a diverse range of biological activities, offering promising prospects for the treatment of diseases hallmarked by oxidative stress and deregulation of cell death pathways. Its protective potential against oxidative stress is also promising for alleviating the side effects of chemotherapy. This review explores the potential therapeutic implications of afzelin, including its capacity to mitigate oxidative stress, modulate inflammation, and promote cellular regeneration in neurodegenerative and cancer diseases.

Impact of voluntary exercise training on the metabolic and behavioral characteristics of the rTg4510 transgenic mouse model of frontotemporal dementia

Frontotemporal dementia (FTD) is a neurodegenerative disorder that affects the frontal and temporal lobes of the brain, primarily in individuals under 65 years of age, and is the second most common form of dementia worldwide. There is no cure for FTD and current treatments offer limited symptomatic relief. Regular physical activity exhibits cognitive and neuroprotective benefits in healthy individuals and in various neurodegenerative diseases, such as Alzheimer's disease, but few studies have examined its efficacy in FTD. Accordingly, we investigated the impact of voluntary exercise training (VET) on the metabolic and behavioral characteristics of the rTg4510 transgenic mouse model of familial FTD. We show that regardless of genotype, VET increased energy expenditure, decreased sleep duration, and improved long-term memory in rTg4510 mice and WT littermates. Moreover, VET appeared to improve hyperactivity, a common feature of FTD, in rTg4510 mice. Although further work is required, these findings provide important insights into the potential benefits of physical activity in FTD.

Distinctive cell-free DNA methylation characterizes presymptomatic genetic frontotemporal dementia

OBJECTIVE

Methylation of plasma cell-free DNA (cfDNA) has potential as a marker of brain damage in neurodegenerative diseases such as frontotemporal dementia (FTD). Here, we study methylation of cfDNA in presymptomatic and symptomatic carriers of genetic FTD pathogenic variants, next to healthy controls.

METHODS

cfDNA was isolated from cross-sectional plasma of 10 presymptomatic carriers (4 C9orf72, 4 GRN, and 2 MAPT), 10 symptomatic carriers (4 C9orf72, 4 GRN, and 2 MAPT), and 9 healthy controls. Genome-wide methylation of cfDNA was determined using a high-resolution sequencing technique (MeD-seq). Cumulative scores based on the identified differentially methylated regions (DMRs) were estimated for presymptomatic carriers (vs. controls and symptomatic carriers), and reevaluated in a validation cohort (8 presymptomatic: 3 C9orf72, 3 GRN, and 2 MAPT; 26 symptomatic: 7 C9orf72, 6 GRN, 12 MAPT, and 1 TARDBP; 13 noncarriers from genetic FTD families).

RESULTS

Presymptomatic carriers showed a distinctive methylation profile compared to healthy controls and symptomatic carriers. Cumulative DMR scores in presymptomatic carriers enabled to significantly differentiate presymptomatic carriers from healthy controls (p < 0.001) and symptomatic carriers (p < 0.001). In the validation cohort, these scores differentiated presymptomatic carriers from symptomatic carriers (p ≤ 0.007) only. Transcription-start-site methylation in presymptomatic carriers, generally associated with gene downregulation, was enriched for genes involved in ubiquitin-dependent processes, while gene body methylation, generally associated with gene upregulation, was enriched for genes involved in neuronal cell processes.

INTERPRETATION

A distinctive methylation profile of cfDNA characterizes the presymptomatic stage of genetic FTD, and could reflect neuronal death in this stage.

Treatment Efficacy of Pharmacotherapies for Frontotemporal Dementia: A Network Meta-Analysis of Randomized Controlled Trials

BACKGROUND

The neuropsychiatric symptoms of frontotemporal dementia (FTD) have a profound negative impact on disease outcomes and care burden. Available pharmacotherapies might be supported by small-scale randomized controlled trials (RCTs); however, clinical recommendations might not be conclusive.

METHODS

We systematically searched several databases from inception to April 30, 2022, for RCTs of drug therapy in patients with FTD and neuropsychiatric symptoms (primary outcome). Secondary outcomes included changes in caregiver stress, daily interactive activities, cognitive function, and acceptability (adverse event or dropout rates). The network meta-analysis (NMA) procedure was performed under the frequency model, showing effect sizes as standardized mean differences (SMD) or odds ratios (OR) with 95% confidence intervals (95% CIs).

RESULTS

Seven RCTs with 243 participants were included. Compared with placebo, high-dose oxytocin (72 international units) was associated with the greatest improvement in patients' neuropsychiatric symptoms (SMD = -1.17, 95% CIs = -2.25 to -0.08, z = -2.10, p = 0.035). Piracetam significantly worsened neuropsychiatric symptoms (SMD = 3.48, 95% CIs = 1.58 to 5.37, z = 3.60, p < 0.001) and caregiver stress (SMD = 2.40, 95% CIs = 0.80-4.01, z = 2.94, p = 0.003). Trazodone had significantly higher rates of adverse events (OR = 9.53, 95% CIs = 1.85-49.20, z = 2.69, p = 0.007). No pharmacological intervention significantly benefited cognitive function.

CONCLUSIONS

This study provides the first NMA for clinical recommendation to support the use of high-dose oxytocin and caution regarding the use of piracetam for neuropsychiatric symptoms in patients with FTD.

NOX-induced oxidative stress is a primary trigger of major neurodegenerative disorders

Neurodegenerative diseases (NDDs) causing cognitive impairment and dementia are difficult to treat due to the lack of understanding of primary initiating factors. Meanwhile, major sporadic NDDs share many risk factors and exhibit similar pathologies in their early stages, indicating the existence of common initiation pathways. Glucose hypometabolism associated with oxidative stress is one such primary, early and shared pathology, and a likely major cause of detrimental disease-associated cascades; targeting this common pathology may therefore be an effective preventative strategy for most sporadic NDDs. However, its exact cause and trigger remain unclear. Recent research suggests that early oxidative stress caused by NADPH oxidase (NOX) activation is a shared initiating mechanism among major sporadic NDDs and could prove to be the long-sought ubiquitous NDD trigger. We focus on two major NDDs - Alzheimer's disease (AD) and Parkinson's disease (PD), as well as on acquired epilepsy which is an increasingly recognized comorbidity in NDDs. We also discuss available data suggesting the relevance of the proposed mechanisms to other NDDs. We delve into the commonalities among these NDDs in neuroinflammation and NOX involvement to identify potential therapeutic targets and gain a deeper understanding of the underlying causes of NDDs.

Development of super-specific epigenome editing by targeted allele-specific DNA methylation

BACKGROUND

Epigenome editing refers to the targeted reprogramming of genomic loci using an EpiEditor which may consist of an sgRNA/dCas9 complex that recruits DNMT3A/3L to the target locus. Methylation of the locus can lead to a modulation of gene expression. Allele-specific DNA methylation (ASM) refers to the targeted methylation delivery only to one allele of a locus. In the context of diseases caused by a dominant mutation, the selective DNA methylation of the mutant allele could be used to repress its expression but retain the functionality of the normal gene.

RESULTS

To set up allele-specific targeted DNA methylation, target regions were selected from hypomethylated CGIs bearing a heterozygous SNP in their promoters in the HEK293 cell line. We aimed at delivering maximum DNA methylation with highest allelic specificity in the targeted regions. Placing SNPs in the PAM or seed regions of the sgRNA, we designed 24 different sgRNAs targeting single alleles in 14 different gene loci. We achieved efficient ASM in multiple cases, such as ISG15, MSH6, GPD1L, MRPL52, PDE8A, NARF, DAP3, and GSPT1, which in best cases led to five to tenfold stronger average DNA methylation at the on-target allele and absolute differences in the DNA methylation gain at on- and off-target alleles of > 50%. In general, loci with the allele discriminatory SNP positioned in the PAM region showed higher success rate of ASM and better specificity. Highest DNA methylation was observed on day 3 after transfection followed by a gradual decline. In selected cases, ASM was stable up to 11 days in HEK293 cells and it led up to a 3.6-fold change in allelic expression ratios.

CONCLUSIONS

We successfully delivered ASM at multiple genomic loci with high specificity, efficiency and stability. This form of super-specific epigenome editing could find applications in the treatment of diseases caused by dominant mutations, because it allows silencing of the mutant allele without repression of the expression of the normal allele thereby minimizing potential side-effects of the treatment.

Anti-Neurodegenerating Activity: Structure-Activity Relationship Analysis of Flavonoids

An anti-neurodegeneration activity study was carried out for 80 flavonoid compounds. The structure-activity analysis of the structures was carried out by performing three different anti-neurodegeneration screening tests, showing that in these structures, the presence of a hydroxy substituent group at position C3' as well as C5' of ring B and a methoxy substituent group at the C7 position of ring A play a vital role in neuroprotective and antioxidant as well as anti-inflammatory activity. Further, we found structure (5) was the top-performing active structure out of 80 structures. Subsequently, a molecular docking study was carried out for the 3 lead flavonoid compounds (4), (5), and (23) and 21 similar hypothetical proposed structures to estimate the binding strength between the tested compounds and proteins potentially involved in disease causation. Ligand-based pharmacophores were generated to guide future drug design studies.

Differential diagnosis of neurodegenerative dementias with the explainable MRI based machine learning algorithm MUQUBIA

Biomarker-based differential diagnosis of the most common forms of dementia is becoming increasingly important. Machine learning (ML) may be able to address this challenge. The aim of this study was to develop and interpret a ML algorithm capable of differentiating Alzheimer's dementia, frontotemporal dementia, dementia with Lewy bodies and cognitively normal control subjects based on sociodemographic, clinical, and magnetic resonance imaging (MRI) variables. 506 subjects from 5 databases were included. MRI images were processed with FreeSurfer, LPA, and TRACULA to obtain brain volumes and thicknesses, white matter lesions and diffusion metrics. MRI metrics were used in conjunction with clinical and demographic data to perform differential diagnosis based on a Support Vector Machine model called MUQUBIA (Multimodal Quantification of Brain whIte matter biomArkers). Age, gender, Clinical Dementia Rating (CDR) Dementia Staging Instrument, and 19 imaging features formed the best set of discriminative features. The predictive model performed with an overall Area Under the Curve of 98%, high overall precision (88%), recall (88%), and F1 scores (88%) in the test group, and good Label Ranking Average Precision score (0.95) in a subset of neuropathologically assessed patients. The results of MUQUBIA were explained by the SHapley Additive exPlanations (SHAP) method. The MUQUBIA algorithm successfully classified various dementias with good performance using cost-effective clinical and MRI information, and with independent validation, has the potential to assist physicians in their clinical diagnosis.

C-terminal TMEM106B fragments in human brain correlate with disease-associated TMEM106B haplotypes

Transmembrane protein 106B (TMEM106B) is a tightly regulated glycoprotein predominantly localized to endosomes and lysosomes. Genetic studies have implicated TMEM106B haplotypes in the development of multiple neurodegenerative diseases with the strongest effect in frontotemporal lobar degeneration with TDP-43 pathology (FTLD-TDP), especially in progranulin (GRN) mutation carriers. Recently, cryo-electron microscopy studies showed that a C-terminal fragment (CTF) of TMEM106B (amino acid residues 120-254) forms amyloid fibrils in the brain of patients with FTLD-TDP, but also in brains with other neurodegenerative conditions and normal ageing brain. The functional implication of these fibrils and their relationship to the disease-associated TMEM106B haplotype remain unknown. We performed immunoblotting using a newly developed antibody to detect TMEM106B CTFs in the sarkosyl-insoluble fraction of post-mortem human brain tissue from patients with different proteinopathies (n = 64) as well as neuropathologically normal individuals (n = 10) and correlated the results with age and TMEM106B haplotype. We further compared the immunoblot results with immunohistochemical analyses performed in the same study population. Immunoblot analysis showed the expected ∼30 kDa band in the sarkosyl-insoluble fraction of frontal cortex tissue in at least some individuals with each of the conditions evaluated. Most patients with GRN mutations showed an intense band representing TMEM106B CTF, whereas in most neurologically normal individuals it was absent or much weaker. In the overall cohort, the presence of TMEM106B CTFs correlated strongly with both age (rs = 0.539, P < 0.001) and the presence of the TMEM106B risk haplotype (rs = 0.469, P < 0.001). Although there was a strong overall correlation between the results of immunoblot and immunohistochemistry (rs = 0.662, P < 0.001), 27 cases (37%) were found to have higher amounts of TMEM106B CTFs detected by immunohistochemistry, including most of the older individuals who were neuropathologically normal and individuals who carried two protective TMEM106B haplotypes. Our findings suggest that the formation of sarkosyl-insoluble TMEM106B CTFs is an age-related feature which is modified by TMEM106B haplotype, potentially underlying its disease-modifying effect. The discrepancies between immunoblot and immunohistochemistry in detecting TMEM106B pathology suggests the existence of multiple species of TMEM106B CTFs with possible biological relevance and disease implications.

Disease-specific selective vulnerability and neuroimmune pathways in dementia revealed by single cell genomics

The development of successful therapeutics for dementias requires an understanding of their shared and distinct molecular features in the human brain. We performed single-nuclear RNAseq and ATACseq in Alzheimer disease (AD), Frontotemporal degeneration (FTD), and Progressive Supranuclear Palsy (PSP), analyzing 40 participants, yielding over 1.4M cells from three brain regions ranging in vulnerability and pathological burden. We identify 35 shared disease-associated cell types and 14 that are disease-specific, replicating those previously identified in AD. Disease - specific cell states represent molecular features of disease-specific glial-immune mechanisms and neuronal vulnerability in each disorder, layer 4/5 intra-telencephalic neurons in AD, layer 2/3 intra-telencephalic neurons in FTD, and layer 5/6 near-projection neurons in PSP. We infer intrinsic disease-associated gene regulatory networks, which we empirically validate by chromatin footprinting. We find that causal genetic risk acts in specific neuronal and glial cells that differ across disorders, primarily non-neuronal cells in AD and specific neuronal subtypes in FTD and PSP. These data illustrate the heterogeneous spectrum of glial and neuronal composition and gene expression alterations in different dementias and identify new therapeutic targets by revealing shared and disease-specific cell states.

Terahertz waves regulate the mechanical unfolding of tau pre-mRNA hairpins

Intermolecular interactions, including hydrogen bonds, dominate the pairing and unpairing of nucleic acid chains in the transfer process of genetic information. The energy of THz waves just matches with the weak interactions, so THz waves may interact with biomolecules. Here, the dynamic effects of THz electromagnetic (EM) waves on the mechanical unfolding process of RNA hairpins (WT-30nt and its mutants, rHP, SARS-CoV-2, and SRV-1 SF206) are investigated using steered molecular dynamics (SMD) simulations. The results show that THz waves can either promote the unfolding of the double helix of the RNA hairpin during the initial unfolding phase (4-21.8 THz) or significantly enhance (23.8 and 25.5 THz) or weaken (37.4 and 41.2 THz) its structural stability during unfolding. Our findings have important implications for applying THz waves to regulate dynamic deconvolution processes, such as gene replication, transcription, and translation.

HnRNP Pathologies in Frontotemporal Lobar Degeneration

Frontotemporal dementia (FTD) is the second most common form of young-onset (<65 years) dementia. Clinically, it primarily manifests as a disorder of behavioural, executive, and/or language functions. Pathologically, frontotemporal lobar degeneration (FTLD) is the predominant cause of FTD. FTLD is a proteinopathy, and the main pathological proteins identified so far are tau, TAR DNA-binding protein 43 (TDP-43), and fused in sarcoma (FUS). As TDP-43 and FUS are members of the heterogeneous ribonucleic acid protein (hnRNP) family, many studies in recent years have expanded the research on the relationship between other hnRNPs and FTLD pathology. Indeed, these studies provide evidence for an association between hnRNP abnormalities and FTLD. In particular, several studies have shown that multiple hnRNPs may exhibit nuclear depletion and cytoplasmic mislocalisation within neurons in FTLD cases. However, due to the diversity and complex association of hnRNPs, most studies are still at the stage of histological discovery of different hnRNP abnormalities in FTLD. We herein review the latest studies relating hnRNPs to FTLD. Together, these studies outline an important role of multiple hnRNPs in the pathogenesis of FTLD and suggest that future research into FTLD should include the whole spectrum of this protein family.

Combining semi-quantitative rating and automated brain volumetry in MRI evaluation of patients with probable behavioural variant of fronto-temporal dementia: an added value for clinical practise?

PURPOSE

To evaluate the diagnostic value of combined semiquantitative and quantitative assessment of brain atrophy in the diagnostic workup of the behavioural-variant of frontotemporal dementia (bvFTD).

METHODS

Three neuroradiologists defined brain atrophy grading and identified atrophy pattern suggestive of bvFTD on 3D-T1 brain MRI of 112 subjects using a semiquantitative rating scale (Kipps'). A quantitative atrophy assessment was performed using two different automated software (Quantib® ND and Icometrix®). A combined semiquantitative and quantitative assessment of brain atrophy was made to evaluate the improvement in brain atrophy grading to identify probable bvFTD patients.

RESULTS

Observers' performances in the diagnosis of bvFTD were very good for Observer 1 (k value = 0.881) and 2 (k value = 0.867), substantial for Observer 3 (k value = 0.741). Semiquantitative atrophy grading of all the observers showed a moderate and a poor correlation with the volume values calculated by Icometrix® and by Quantib® ND, respectively. For the definition of neuroradiological signs presumptive of bvFTD, the use of Icometrix® software improved the diagnostic accuracy for Observer 1 resulting in an AUC of 0.974, and for Observer 3 resulting in a AUC of 0.971 (p-value < 0.001). The use of Quantib® ND software improved the diagnostic accuracy for Observer 1 resulting in an AUC of 0.974, and for Observer 3 resulting in a AUC of 0.977 (p-value < 0.001). No improvement was observed for Observer 2.

CONCLUSION

Combining semiquantitative and quantitative brain imaging evaluation allows to reduce discrepancies in the neuroradiological diagnostic workup of bvFTD by different readers.

Autoimmunity and Frontotemporal Lobar Degeneration: From Laboratory Study to Clinical Practice

Frontotemporal lobar degeneration (FTLD) is a group of neurodegenerative diseases with heterogenous clinical, genetic, and pathological characteristics that show similar impairment of areas in the frontal and/or temporal lobes. Prime doctors' lack of awareness of this complex disease makes early identification and accurate intervention difficult. Autoimmune diseases and autoantibodies are manifestations of different levels of autoimmune reactions. This review presents research findings examining the relationship between autoimmunity and FTLD in terms of autoimmune diseases and autoantibodies with a focus on identifying potential diagnosis and treatment approaches. The findings indicate that the same or similar pathophysiological mechanisms may exist from clinical, genetic, and pathological perspectives. However, the existing evidence is not sufficient to extract substantial conclusions. On the basis of the current situation, we propose future research patterns using prospective studies on large populations and combined clinical and experimental research. Autoimmune reactions or, more generally, inflammatory reactions should receive increased attention from doctors and scientists of all disciplines.

Behavioural disinhibition in frontotemporal dementia investigated within an ecological framework

Disinhibition is a core symptom in behavioural variant frontotemporal dementia (bvFTD) particularly affecting the daily lives of both patients and caregivers. Yet, characterisation of inhibition disorders is still unclear and management options of these disorders are limited. Questionnaires currently used to investigate behavioural disinhibition do not differentiate between several subtypes of disinhibition, encompass observation biases and lack of ecological validity. In the present work, we explored disinhibition in an original semi-ecological situation, by distinguishing three categories of disinhibition: compulsivity, impulsivity and social disinhibition. First, we measured prevalence and frequency of these disorders in 23 bvFTD patients and 24 healthy controls (HC) in order to identify the phenotypical heterogeneity of disinhibition. Then, we examined the relationships between these metrics, the neuropsychological scores and the behavioural states to propose a more comprehensive view of these neuropsychiatric manifestations. Finally, we studied the context of occurrence of these disorders by investigating environmental factors potentially promoting or reducing them. As expected, we found that patients were more compulsive, impulsive and socially disinhibited than HC. We found that 48% of patients presented compulsivity (e.g., repetitive actions), 48% impulsivity (e.g., oral production) and 100% of the patients group showed social disinhibition (e.g., disregards for rules or investigator). Compulsivity was negatively related with emotions recognition. BvFTD patients were less active if not encouraged in an activity, and their social disinhibition decreased as activity increased. Finally, impulsivity and social disinhibition decreased when patients were asked to focus on a task. Summarising, this study underlines the importance to differentiate subtypes of disinhibition as well as the setting in which they are exhibited, and points to stimulating area for non-pharmacological management.

Mechanistic considerations and biomarkers level in nickel-induced neurodegenerative diseases: An updated systematic review

The environment has been implicated to be a strong determinant of brain health with higher risk of neurodegeneration. The drastic rise in the prevalence of neurodegenerative diseases (NDDs) including Alzheimer's disease (AD), Parkinson's disease (PD), autism spectrum disorder (ASD), multiple sclerosis (MS) etc., supports the idea that environmental factors may play a major role in NDDs aetiology. Nickel is one of the listed environmental metals reported to pose a serious threat to human health. This paper reported available studies on nickel level in NDDs covering both animal and human studies. Different databases were searched for articles reporting the main neurotoxicity mechanisms and the concentration of nickel in fluids and tissues of NDDs patients compared to controls. Data were extracted and synthesized by ensuring the articles were related to nickel and NDDs. Various mechanisms were reported as oxidative stress, disturbances in mitochondrial membrane potential, trace elements homeostasis destabilization, etc. Nickel was found elevated in biological fluids as blood, serum/plasma and CSF and in the brain of NDDs, as a consequence of unintentional exposure thorough nickel-contaminated air, food, water, and skin contact. In addition, after exposure to nickel, the concentration of markers of lipid peroxidation were increased, while some antioxidant defence systems decreased. Thus, the reduction in the exposure to nickel contaminant may hold a promise in reducing the incidence of NDDs.

Cognitive Impairment in Older Adults: Epidemiology, Diagnosis, and Treatment

Cognitive impairment and dementia affect dozens of millions of people worldwide and cause significant distress to patients and caregivers and a financial burden to families and health care systems. Careful history-taking, cognitive and physical examination, and supplemental neuroimaging and fluid-based biomarkers can accurately diagnose neurocognitive disorders. Management includes non-pharmacological and pharmacological treatments tailored to the etiology and to the individual.

Protein Misfolding and Aggregation in the Brain: Common Pathogenetic Pathways in Neurodegenerative and Mental Disorders

Mental disorders represent common brain diseases characterized by substantial impairments of social and cognitive functions. The neurobiological causes and mechanisms of psychopathologies still have not been definitively determined. Various forms of brain proteinopathies, which include a disruption of protein conformations and the formation of protein aggregates in brain tissues, may be a possible cause behind the development of psychiatric disorders. Proteinopathies are known to be the main cause of neurodegeneration, but much less attention is given to the role of protein impairments in psychiatric disorders' pathogenesis, such as depression and schizophrenia. For this reason, the aim of this review was to discuss the potential contribution of protein illnesses in the development of psychopathologies. The first part of the review describes the possible mechanisms of disruption to protein folding and aggregation in the cell: endoplasmic reticulum stress, dysfunction of chaperone proteins, altered mitochondrial function, and impaired autophagy processes. The second part of the review addresses the known proteins whose aggregation in brain tissue has been observed in psychiatric disorders (amyloid, tau protein, α-synuclein, DISC-1, disbindin-1, CRMP1, SNAP25, TRIOBP, NPAS3, GluA1, FABP, and ankyrin-G).

Homocysteine, Cognitive Functions, and Degenerative Dementias: State of the Art

There is strong evidence that homocysteine is a risk factor not only for cerebrovascular diseases but also for degenerative dementias. A recent consensus statement renewed the importance and the role of high levels of homocysteine in cognitive decline in several forms of degenerative dementia, such as Alzheimer's disease. Although the molecular mechanisms by which homocysteine causes cell dysfunction are known, both the impact of homocysteine on specific cognitive functions and the relationship between homocysteine level and non-Alzheimer dementias have been poorly investigated. Most of the studies addressing the impact of hyperhomocysteinemia on dementias have not examined the profile of performance across different cognitive domains, and have only relied on screening tests, which provide a very general and coarse-grained picture of the cognitive status of the patients. Yet, trying to understand whether hyperhomocysteinemia is associated with the impairment of specific cognitive functions would be crucial, as it would be, in parallel, learning whether some brain circuits are particularly susceptible to the damage caused by hyperhomocysteinemia. These steps would allow one to (i) understand the actual role of homocysteine in the pathogenesis of cognitive decline and (ii) improve the diagnostic accuracy, differential diagnosis and prognostic implications. This review is aimed at exploring and revising the state of the art of these two strictly related domains. Suggestions for future research are provided.

White Blood Cell and Platelet Counts Are Not Suitable as Biomarkers in the Differential Diagnostics of Dementia

Apart from Alzheimer’s disease (AD), no biomarkers for the differential diagnosis of dementia have been established to date. Inflammatory processes contribute to the pathogenesis of dementia subtypes, e.g., AD or frontotemporal dementia (FTD). In the context of cancer or cardiovascular diseases, white blood cell (WBC) populations and platelet counts, as well as C-reactive protein (CRP), have emerged as biomarkers. Their clinical relevance in dementia, however, is currently only insufficiently investigated. In the present study, hematological and inflammatory parameters were measured in the peripheral blood of 97 patients admitted to the gerontopsychiatric ward of Hannover Medical School, a university hospital in Germany, for dementia assessment. The study population comprised 20 non-demented, depressed patients (control group) and 77 demented patients who were assigned to five different groups based on their underlying dementia etiology: AD, n = 33; vascular dementia, n = 12; mixed dementia, n = 21; FTD, n = 5; and Korsakoff syndrome, n = 6. We observed neither statistically significant differences regarding total WBC populations, platelet counts, neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio, nor CRP levels between the control group and the five dementia groups. CRP levels tended to be higher in patients with Korsakoff syndrome than in the control group and in AD patients. Thus, CRP could possibly play a role in the differential diagnosis of dementia. This should be investigated further in future prospective studies with larger sample sizes. WBC and platelet counts, by contrast, do not appear to be suitable biomarkers in the differential diagnosis of dementia.

Single cell transcriptomic profiling of a neuron-astrocyte assembloid tauopathy model

The use of iPSC derived brain organoid models to study neurodegenerative disease has been hampered by a lack of systems that accurately and expeditiously recapitulate pathogenesis in the context of neuron-glial interactions. Here we report development of a system, termed AstTau, which propagates toxic human tau oligomers in iPSC derived neuron-astrocyte assembloids. The AstTau system develops much of the neuronal and astrocytic pathology observed in tauopathies including misfolded, phosphorylated, oligomeric, and fibrillar tau, strong neurodegeneration, and reactive astrogliosis. Single cell transcriptomic profiling combined with immunochemistry characterizes a model system that can more closely recapitulate late-stage changes in adult neurodegeneration. The transcriptomic studies demonstrate striking changes in neuroinflammatory and heat shock protein (HSP) chaperone systems in the disease process. Treatment with the HSP90 inhibitor PU-H71 is used to address the putative dysfunctional HSP chaperone system and produces a strong reduction of pathology and neurodegeneration, highlighting the potential of AstTau as a rapid and reproducible tool for drug discovery.

Advances in Treatment of Frontotemporal Dementia

In this review, the authors explored the clinical features of frontotemporal dementia (FTD), focusing on treatment. The clinical features of FTD are unique, with disinhibition, apathy, loss of empathy, and compulsions common. Motor changes occur later in the illness. The two major proteins that aggregate in the brain with FTD are tau and TDP-43, whereas a minority of patients aggregate FET proteins, primarily the FUS protein. Genetic causes include mutations in MAPT, GRN, and C9orf72. There are no medications that can slow FTD progression, although new therapies for the genetic forms of FTD are moving into clinical trials. Once a diagnosis is made, therapies should begin, focusing on the family and the patient. In the setting of FTD, families experience a severe burden associated with caregiving, and the clinician should focus on alleviating this burden. Advice around legal and financial issues is usually helpful. Careful consideration of environmental changes to cope with abnormal behaviors is essential. Most compounds that have been used to treat dementia of the Alzheimer's disease type are not effective in FTD, and cholinesterase inhibitors and memantine should be avoided. Although the data are scant, there is some evidence that antidepressants and second-generation antipsychotics may help individual patients.

Loss of Cholinergic Receptor Muscarinic 1 (CHRM1) Protein in the Hippocampus and Temporal Cortex of a Subset of Individuals with Alzheimer’s Disease, Parkinson’s Disease, or Frontotemporal Dementia: Implications for Patient Survival

Background: Dysfunction of cholinergic neurotransmission is a hallmark of Alzheimer’s disease (AD); forming the basis for using acetylcholine (ACh) esterase (AChE) inhibitors to mitigate symptoms of ACh deficiency in AD. The Cholinergic Receptor Muscarinic 1 (CHRM1) is highly expressed in brain regions impaired by AD. Previous analyses of postmortem AD brains revealed unaltered CHRM1 mRNA expression compared to normal brains. However, the CHRM1 protein level in AD and other forms of dementia has not been extensively studied. Reduced expression of CHRM1 in AD patients may explain the limited clinical efficacy of AChE inhibitors. Objective: To quantify CHRM1 protein in the postmortem hippocampus and temporal cortex of AD, Parkinson’s disease (PD), and frontotemporal dementia (FTD) patients. Methods: Western blotting was performed on postmortem hippocampus (N = 19/73/7/9: unaffected/AD/FTD/PD) and temporal cortex (N = 9/74/27: unaffected/AD/PD) using a validated anti-CHRM1 antibody. Results: Quantification based on immunoblotting using a validated anti-CHRM1 antibody revealed a significant loss of CHRM1 protein level (<50%) in the hippocampi (78% AD, 66% PD, and 85% FTD) and temporal cortices (56% AD and 42% PD) of dementia patients. Loss of CHRM1 in the temporal cortex was significantly associated with early death (<65–75 years) for both AD and PD patients. Conclusion: Severe reduction of CHRM1 in a subset of AD and PD patients can explain the reported low efficacy of AChE inhibitors as a mitigating treatment for dementia patients. Based on this study, it can be suggested that future research should prioritize therapeutic restoration of CHRM1 protein levels in cholinergic neurons.

A Combination of Neurofilament Light, Glial Fibrillary Acidic Protein, and Neuronal Pentraxin-2 Discriminates Between Frontotemporal Dementia and Other Dementias

Background: The differential diagnosis of frontotemporal dementia (FTD) is still a challenging task due to its symptomatic overlap with other neurological diseases and the lack of biofluid-based biomarkers. Objective: To investigate the diagnostic potential of a combination of novel biomarkers in cerebrospinal fluid (CSF) and blood. Methods: We included 135 patients from the Centre for Memory Disturbances, University of Perugia, with the diagnoses FTD (n = 37), mild cognitive impairment due to Alzheimer’s disease (MCI-AD, n = 47), Lewy body dementia (PDD/DLB, n = 22), and cognitively unimpaired patients as controls (OND, n = 29). Biomarker levels of neuronal pentraxin-2 (NPTX2), neuronal pentraxin receptor, neurofilament light (NfL) and glial fibrillary acidic protein (GFAP) were measured in CSF, as well as NfL and GFAP in serum. We assessed biomarker differences by analysis of covariance and generalized linear models (GLM). We performed receiver operating characteristics analyses and Spearman correlation to determine biomarker associations. Results: CSF NPTX2 and serum GFAP levels varied most between diagnostic groups. The combination of CSF NPTX2, serum NfL and serum GFAP differentiated FTD from the other groups with good accuracy FTD versus MCI-AD: area under the curve (AUC [95% CI] = 0.89 [0.81–0.96]; FTD versus PDD/DLB: AUC = 0.82 [0.71–0.93]; FTD versus OND: AUC = 0.80 [0.70–0.91]). CSF NPTX2 and serum GFAP correlated positively only in PDD/DLB (ρ= 0.56, p <  0.05). NPTX2 and serum NfL did not correlate in any of the diagnostic groups. Serum GFAP and serum NfL correlated positively in all groups (ρ= 0.47–0.74, p <  0.05). Conclusion: We show the combined potential of CSF NPTX2, serum NfL, and serum GFAP to differentiate FTD from other neurodegenerative disorders.

An Indonesian elderly with primary progressive aphasia and behavioral variant of frontotemporal dementia: A case report and review article

Background

Frontotemporal dementia (FTD) or Pick's disease, is the second most frequent cause of primary degenerative dementia in those between 55 and 65 years old.

Case presentation

A 57-year-old Indonesian female reported family that six months until one year prior to the presentation of her first symptoms, the patient had problems with memory, particularly short-term memory loss, with the patient unable to remember the task she was doing on time. The electroencephalogram revealed slowing background cerebral activity and diffuse slowing activity, indicating encephalopathy diffuse moderate state. CSF showed no pleocytosis and no elevated CSF Protein, but we did not perform tau level. She underwent brain magnetic resonance imaging (MRI) because of her aggression and impulsiveness. Brain MRI was notable for bilateral frontal and temporal atrophy. Incidentally, there was the leptomeningeal enhancement of the bilateral frontotemporal lobe. The patients were administered Haloperidol 0.5 mg orally twice daily, Donepezil 5 mg oral once daily, Aripiprazole 2.5 mg once daily, and Memantine 10 mg twice daily. The patient was discharged one week after admission and was started on antiviral therapy Acyclovir 800 mg 5 times a day for 14 days. The patient had shown more cooperative and less agitative.

Discussion

We report that FTD aims to help improve effective management.

Conclusion

Awareness of FTD needs to be increased even though this case is sporadic because it does not demand the possibility of this case occurring at a young age.

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FTD is a rare case of dementia in the elderly.

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A FTD suspect assessed patients with a lack of judgment, erratic behavior, and unresponsiveness.

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FTD is often misdiagnosed as Alzheimer's disease.

New Statement about NRF2 in Amyotrophic Lateral Sclerosis and Frontotemporal Dementia

Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are related neurodegenerative disorders displaying substantial overlay, although there are substantial differences at the molecular level. Currently, there is no effective treatment for these diseases. The transcription factor NRF2 has been postulated as a promising therapeutic target as it is capable of modulating key pathogenic events affecting cellular homeostasis. However, there is little experimental evidence on the status of this pathway in both ALS and FTD. Therefore, in this work, we wanted to carry out an exhaustive analysis of this signaling pathway in both transgenic mouse models (ALS and FTD) and human samples from patients with sporadic ALS (sALS) versus controls. In samples from patients with sALS and in the transgenic model with overexpression of TDP-43A315T, we observed a significant increase in the NRF2/ARE pathway in the motor cortex and the spinal cord, indicating that NRF2 antioxidant signaling was being induced, but it was not enough to reach cellular homeostasis. On the other hand, in the transgenic FTD model with overexpression of the TDP-43WT protein in forebrain neurons, a significantly decreased expression of NQO1 in the prefrontal cortex was seen, which cannot be attributed to alterations in the NRF2 pathway. Our results show that NRF2 signature is differently affected for ALS and FTD.

The Omnipresence of DYRK1A in Human Diseases

The increasing population will challenge healthcare, particularly because the worldwide population has never been older. Therapeutic solutions to age-related disease will be increasingly critical. Kinases are key regulators of human health and represent promising therapeutic targets for novel drug candidates. The dual-specificity tyrosine-regulated kinase (DYRKs) family is of particular interest and, among them, DYRK1A has been implicated ubiquitously in varied human diseases. Herein, we focus on the characteristics of DYRK1A, its regulation and functional role in different human diseases, which leads us to an overview of future research on this protein of promising therapeutic potential.

A case of spontaneous intracranial hypotension in a 45-year-old male with headache, behavior changes and altered mental status

Spontaneous intracranial hypotension is a rare disease that results from low cerebrospinal fluid (CSF) volume caused by leakage of CSF from the spine in the absence of lumbar puncture, spine surgery, or intervention. The most common presentation is the headache that is usually but not invariably orthostatic. The underlying pathology is a CSF leak resulting from dural weakness involving the nerve root sleeves, ventral dural tears associated with calcified disc herniations, or CSF venous fistula. In severe cases, neuropsychiatric symptoms and changes in mental status may develop. Some case reports also mention gait disturbances, slurred speech, and urinary incontinence. The constellation of neuropsychiatric symptoms similar to behavior variant frontotemporal dementia in the presence of "brain sag" on MRI is known as frontotemporal brain sagging syndrome, first described by Wicklund et al. (4). The disease presents a diagnostic challenge to the primary care physicians, who are the first to see these patients. Brain and spine imaging is key to diagnoses but requires a high index of suspicion, as very rarely are all classic findings of intracranial hypotension present in the same patient. Here we discuss a case of spontaneous intracranial hypotension in a 45-year-old male patient who presented with headache, drowsiness, incoherent speech, behavior symptoms, and altered mental status.

Comparing Medial Temporal Atrophy Between Early-Onset Semantic Dementia and Early-Onset Alzheimer's Disease Using Voxel-Based Morphometry: A Multicenter MRI Study

BACKGROUND

Early-onset Semantic dementia (EOSD) and early-onset Alzheimer's disease (EOAD) are often difficult to clinically differentiate in the early stages of the diseases because of the overlaps of clinical symptoms such as language symptoms. We compared the degree of atrophy in medial temporal structures between the two types of dementia using the voxel-based specific regional analysis system for Alzheimer's disease (VSRAD).

METHODS

The participants included 29 (age: 61.7±4.5 years) and 39 (age: 60.2±4.9 years) patients with EOSD and EOAD, respectively. The degree of atrophy in medial temporal structures was quantified using the VSRAD for magnetic resonance imaging data. Receiver operating characteristic (ROC) analysis was performed to distinguish patients with EOSD and EOAD using the mean Z score (Z-score) in bilateral medial temporal structures and the absolute value (laterality score) of the laterality of Z-score (| right-left |) for indicating the degree of asymmetrical atrophy in medial temporal structures.

RESULTS

The EOSD group had significantly higher Z and laterality scores than the EOAD group (Zscores: mean ± standard deviation: 3.74±1.05 vs. 1.56±0.81, respectively; P<0.001; laterality score: mean ± standard deviation: 2.35±1.23 vs. 0.68±0.51, respectively; P<0.001). In ROC analysis, the sensitivity and specificity to differentiate EOSD from EOAD by a Z-score of 2.29 were 97% and 85%, respectively and by the laterality score of 1.05 were 93% and 85%, respectively.

CONCLUSION

EOSD leads to more severe and asymmetrical atrophy in medial temporal structures than EOAD. The VSRAD may be useful to distinguish between these dementias that have several clinically similar symptoms.

Psychometric Properties of the Polish Version of the Frontotemporal Dementia Knowledge Scale

INTRODUCTION

Taking into account a progressive increase in the number of individuals affected by dementia and the importance of being knowledgeable about its symptoms, it has become crucial to develop well-validated instruments for measuring knowledge about dementia. The aim of this study was to translate and validate the Frontotemporal Dementia Knowledge Scale (FTDKS) in a Polish population.

METHODS

The FTDKS was translated into the Polish language based on the most highly recommended methodological approaches for translating and validating instruments for cross-cultural healthcare research. Psychometric properties were evaluated in a sample of 869 individuals (general population, healthcare professionals, and caregivers) who completed the questionnaire. The reliability of the FTDKS was tested as an internal consistency using both Cronbach's alpha and McDonald's omega factor analysis. The convergent and discriminant validity was assessed using the Heterotrait-monotrait Ratio of Correlation between scores of FTDKS, vocabulary intelligence, and Alzheimer's Disease Knowledge Scale (AKDS).

RESULTS

The results indicate that the scale produces satisfactory psychometric properties (Cronbach's alpha and McDonald's omega over 0.80). The internal consistency was slightly higher in the population of healthcare professionals and caregivers than among the general population.

DISCUSSION

The internal consistency of the Polish version of FTDKS demonstrates a similar validity to the original version. The FTDKS can be used to evaluate the effectiveness of educational interventions among caregivers, healthcare professionals, and the general population.

Effects of Palmitoylethanolamide on Neurodegenerative Diseases: A Review from Rodents to Humans

Palmitoylethanolamide (PEA) stands out among endogenous lipid mediators for its neuroprotective, anti-inflammatory, and analgesic functions. PEA belonging to the N-acetylanolamine class of phospholipids was first isolated from soy lecithin, egg yolk, and peanut flour. It is currently used for the treatment of different types of neuropathic pain, such as fibromyalgia, osteoarthritis, carpal tunnel syndrome, and many other conditions. The properties of PEA, especially of its micronized or ultra-micronized forms maximizing bioavailability and efficacy, have sparked a series of innovative research to evaluate its possible application as therapeutic agent for neurodegenerative diseases. Neurodegenerative diseases are widespread throughout the world, and although they are numerous and different, they share common patterns of conditions that result from progressive damage to the brain areas involved in mobility, muscle coordination and strength, mood, and cognition. The present review is aimed at illustrating in vitro and in vivo research, as well as human studies, using PEA treatment, alone or in combination with other compounds, in the presence of neurodegeneration. Namely, attention has been paid to the effects of PEA in counteracting neuroinflammatory conditions and in slowing down the progression of diseases, such as Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, Frontotemporal dementia, Amyotrophic Lateral Sclerosis, and Multiple Sclerosis. Literature research demonstrated the efficacy of PEA in addressing the damage typical of major neurodegenerative diseases.

Functional Disabilities and Psychiatric Symptoms in Primary Progressive Aphasia

OBJECTIVE

The aims of this study are to describe the chronology of functional disabilities in primary progressive aphasia (PPA), and to examine associations between psychiatric comorbidities and functional disabilities.

METHODS

We conducted a retrospective data analysis using subjects enrolled at Alzheimer's Disease Research Centers between 2005 and 2019. Data were obtained from the National Alzheimer's Coordinating Center database. We included subjects whose primary diagnosis was PPA. Functional status was coded as a binary variable for the following functions: ambulation, transaction skills, verbal communication, meal preparation, and self-care. Behavioral data derived from the Neuropsychiatric Inventory Questionnaire. Descriptive statistics and cox proportional hazard analyses were used to characterize the emergence of disabilities and their association with psychiatric comorbidities.

RESULTS

Data included 91 subjects with a clinical dementia rating scale of zero at baseline. At the initial visit, no individuals had impairments in self-care, while 7% had impairments in transactions, 3% in ambulation, and 2% in meal preparation. Ninety-three percent had language impairments at the onset of the study, and all by visit 4. By visit 5, 41% of patients had impairments in ambulation and in self-care, 49% were impaired in meal preparation and 70% had impairment in transactions. The presence of anxiety, depression, sleep disturbance and psychosis were all significantly associated with an increased risk for multiple functional disabilities.

CONCLUSION

These findings provide clinicians with guidance for forecasting disabilities and targeting interventions in PPA.

The Complex Mechanisms by Which Neurons Die Following DNA Damage in Neurodegenerative Diseases

Human cells are exposed to numerous exogenous and endogenous insults every day. Unlike other molecules, DNA cannot be replaced by resynthesis, hence damage to DNA can have major consequences for the cell. The DNA damage response contains overlapping signalling networks that repair DNA and hence maintain genomic integrity, and aberrant DNA damage responses are increasingly described in neurodegenerative diseases. Furthermore, DNA repair declines during aging, which is the biggest risk factor for these conditions. If unrepaired, the accumulation of DNA damage results in death to eliminate cells with defective genomes. This is particularly important for postmitotic neurons because they have a limited capacity to proliferate, thus they must be maintained for life. Neuronal death is thus an important process in neurodegenerative disorders. In addition, the inability of neurons to divide renders them susceptible to senescence or re-entry to the cell cycle. The field of cell death has expanded significantly in recent years, and many new mechanisms have been described in various cell types, including neurons. Several of these mechanisms are linked to DNA damage. In this review, we provide an overview of the cell death pathways induced by DNA damage that are relevant to neurons and discuss the possible involvement of these mechanisms in neurodegenerative conditions.

Therapeutic effect of palmitoylethanolamide in cognitive decline: A systematic review and preliminary meta-analysis of preclinical and clinical evidence

Cognitive decline is believed to be associated with neurodegenerative processes involving excitotoxicity, oxidative damage, inflammation, and microvascular and blood-brain barrier dysfunction. Interestingly, research evidence suggests upregulated synthesis of lipid signaling molecules as an endogenous attempt to contrast such neurodegeneration-related pathophysiological mechanisms, restore homeostatic balance, and prevent further damage. Among these naturally occurring molecules, palmitoylethanolamide (PEA) has been independently associated with neuroprotective and anti-inflammatory properties, raising interest into the possibility that its supplementation might represent a novel therapeutic approach in supporting the body-own regulation of many pathophysiological processes potentially contributing to neurocognitive disorders. Here, we systematically reviewed all human and animal studies examining PEA and its biobehavioral correlates in neurocognitive disorders, finding 33 eligible outputs. Studies conducted in animal models of neurodegeneration indicate that PEA improves neurobehavioral functions, including memory and learning, by reducing oxidative stress and pro-inflammatory and astrocyte marker expression as well as rebalancing glutamatergic transmission. PEA was found to promote neurogenesis, especially in the hippocampus, neuronal viability and survival, and microtubule-associated protein 2 and brain-derived neurotrophic factor expression, while inhibiting mast cell infiltration/degranulation and astrocyte activation. It also demonstrated to mitigate β-amyloid-induced astrogliosis, by modulating lipid peroxidation, protein nytrosylation, inducible nitric oxide synthase induction, reactive oxygen species production, caspase3 activation, amyloidogenesis, and tau protein hyperphosphorylation. Such effects were related to PEA ability to indirectly activate cannabinoid receptors and modulate proliferator-activated receptor-α (PPAR-α) activity. Importantly, preclinical evidence suggests that PEA may act as a disease-modifying-drug in the early stage of a neurocognitive disorder, while its protective effect in the frank disorder may be less relevant. Limited human research suggests that PEA supplementation reduces fatigue and cognitive impairment, the latter being also meta-analytically confirmed in 3 eligible studies. PEA improved global executive function, working memory, language deficits, daily living activities, possibly by modulating cortical oscillatory activity and GABAergic transmission. There is currently no established cure for neurocognitive disorders but only treatments to temporarily reduce symptom severity. In the search for compounds able to protect against the pathophysiological mechanisms leading to neurocognitive disorders, PEA may represent a valid therapeutic option to prevent neurodegeneration and support endogenous repair processes against disease progression.

Identification of TMEM106B amyloid fibrils provides an updated view of TMEM106B biology in health and disease

Since the initial identification of TMEM106B as a risk factor for frontotemporal lobar degeneration (FTLD), multiple genetic studies have found TMEM106B variants to modulate disease risk in a variety of brain disorders and healthy aging. Neurodegenerative disorders are typically characterized by inclusions of misfolded proteins and since lysosomes are an important site for cellular debris clearance, lysosomal dysfunction has been closely linked to neurodegeneration. Consequently, many causal mutations or genetic risk variants implicated in neurodegenerative diseases encode proteins involved in endosomal-lysosomal function. As an integral lysosomal transmembrane protein, TMEM106B regulates several aspects of lysosomal function and multiple studies have shown that proper TMEM106B protein levels are crucial for maintaining lysosomal health. Yet, the precise function of TMEM106B at the lysosomal membrane is undetermined and it remains unclear how TMEM106B modulates disease risk. Unexpectedly, several independent groups recently showed that the C-terminal domain (AA120-254) of TMEM106B forms amyloid fibrils in the brain of patients with a diverse set of neurodegenerative conditions. The recognition that TMEM106B can form amyloid fibrils and is present across neurodegenerative diseases sheds new light on TMEM106B as a central player in neurodegeneration and brain health, but also raises important new questions. In this review, we summarize current knowledge and place a decade's worth of TMEM106B research into an exciting new perspective.

Protein synthesis modulation as a therapeutic approach for amyotrophic lateral sclerosis and frontotemporal dementia

Protein synthesis is essential for cells to perform life metabolic processes. Pathological alterations of protein content can lead to particular diseases. Cells have an intrinsic array of mechanisms and pathways that are activated when protein misfolding, accumulation, aggregation or mislocalization occur. Some of them (like the unfolded protein response) represent complex interactions between endoplasmic reticulum sensors and elongation factors that tend to increase expression of chaperone proteins and/or repress translation in order to restore protein homeostasis (also known as proteostasis). This is even more important in neurons, as they are very susceptible to harmful effects associated with protein overload and proteostatic mechanisms are less effective with age. Several neurodegenerative pathologies such as Alzheimer's, Parkinson's, and Huntington's diseases, amyotrophic lateral sclerosis and frontotemporal dementia exhibit a particular molecular signature of distinct, unbalanced protein overload. In amyotrophic lateral sclerosis and frontotemporal dementia, the majority of cases present intracellular inclusions of ubiquitinated transactive response DNA-binding protein of 43 kDa (TDP-43). TDP-43 is an RNA binding protein that participates in RNA metabolism, among other functions. Dysregulation of TDP-43 (e.g. aggregation and mislocalization) can dramatically affect neurons, and this has been linked to disease development. Expression of amyotrophic lateral sclerosis/frontotemporal dementia TDP-43-related mutations in cellular and animal models has been shown to recapitulate key features of the amyotrophic lateral sclerosis/frontotemporal dementia disease spectrum. These variants can be causative of degeneration onset and progression. Most neurodegenerative diseases (including amyotrophic lateral sclerosis and frontotemporal dementia) have no cure at the moment; however, modulating translation has recently emerged as an attractive approach that can be performed at several steps (i.e. regulating activation of initiation and elongation factors, inhibiting unfolded protein response activation or inducing chaperone expression and activity). This review focuses on the features of protein imbalance in neurodegenerative disorders and the relevance of developing therapeutical compounds aiming at restoring proteostasis. We strive to highlight the importance of research on drugs that, not only restore protein imbalance without compromising translational activity of cells, but are also as safe as possible for the patients.

Spanish version of the Frontotemporal Dementia Knowledge Scale: adaptation and validation

BACKGROUND

Frontotemporal dementia (FTD) is a neurodegenerative disease and is one of the most common causes of dementia in people under 65. There is often a significant diagnostic delay, as FTD can be confused with other psychiatric conditions. A lack of knowledge regarding FTD by health professionals is one possible cause for this diagnostic confusion.

OBJECTIVES

The aim of this study was to adapt and validate the Frontotemporal Dementia Knowledge Scale (FTDKS) in Spanish.

METHODS

A translation was done, following cross-cultural adaptation guidelines, which consisted of forward translation, blind back translation, and an analysis by a committee of experts. For the present study, 134 professionals from different health areas responded the Spanish version of the FTDKS. The statistical analysis was performed using R version 4.0.0 "Arbor day" and the Psych, sjPlot packages.

RESULTS

The Spanish version of the FTDKS had good reliability and internal consistency (Cronbach alpha 0.74.). The sample's mean score was 19.78 (range = 4-32, SD 6.3) out of a maximum of 36 points.

CONCLUSIONS

The results obtained show that the Spanish version has good psychometric properties. The FTDKS is applicable in our environment and can be a useful tool to evaluate the knowledge of health professionals regarding frontotemporal dementia.