Search Results (109)

Background and objectives: Frontotemporal dementia (FTD) is a heterogeneous neurodegenerative disorder with autosomal dominant forms most often linked to MAPT, GRN, and C9orf72. We aimed to evaluate the prevalence of pathogenic variants in these genes in a hospital-based cohort of FTD patients assessed at a tertiary referral center in southeastern Serbia. Methods: We studied 58 consecutive patients with FTD spectrum syndromes evaluated at a tertiary referral center. All underwent standardized neurological, neuropsychological, and imaging assessments, and family history was recorded. Genetic testing included validated assays for C9orf72 repeat expansions and next-generation sequencing of MAPT and GRN. Results: Women comprised 53.45% of the cohort. The mean age was 67.88 years, with mean onset at 61.70 years. Behavioral variant FTD predominated (75.87%), while language forms were less frequent. Positive family history was present in 16 patients (27.59%). Pathogenic variants were identified in three individuals (5.17%): two unrelated carriers of the intronic MAPT mutation c.1920+16C>T and one patient with a C9orf72 expansion. No GRN variants were detected. Mutation frequency was 18.75% in familial cases, while none were found among sporadic patients (p = 0.018). Four of nine relatives were asymptomatic MAPT mutation carriers. Conclusions: This first genetic study of FTD in southeastern Serbia revealed a lower mutation frequency than in Northern and Western Europe, but similar to cohorts from Southeastern Europe. The detection of MAPT c.1920+16C>T in two unrelated families extends the geographic range of this splice-site variant and underscores the importance of systematic genetic testing and larger collaborative studies in the Balkans. Full article

Neurodegeneration is intrinsically linked to aging through processes such as oxidative stress, mitochondrial dysfunction, and chronic inflammation. Nuclear factor erythroid 2-related factor 2 (Nrf2) emerges as a central transcription factor regulating these molecular events and promoting cytoprotective responses. In neurodegenerative diseases, notably, frontotemporal dementia (FTD) and Parkinson’s disease (PD), genetic mutations—including MAPT, LRRK2, PINK1, PRKN, and SNCA—have been reported to alter Nrf2 signaling, both in vitro and in vivo. Melatonin, a neurohormone widely known for its strong antioxidant and mitochondria-stabilizing properties, has been shown to activate Nrf2 and restore redox balance in several experimental models of neurodegeneration. Its effects include a reduction in tau hyperphosphorylation, α-synuclein aggregation, and neuroinflammation. While most data are derived from sporadic models of Alzheimer’s disease and PD, emerging evidence supports a role for melatonin in familial forms of FTD and PD as well. Thus, targeting Nrf2 through melatonin may offer a promising approach to mitigating neurodegeneration, especially in the context of mutation-driven pathologies. Further investigation is warranted to explore mutation-specific responses and optimize the therapeutic strategies. Full article

Background/Objectives: Gastrointestinal nematode infections represent a major constraint to sheep production globally, with widespread drug resistance requiring alternative control strategies. Methods: This systematic review combined genome-wide association study findings to understand the genetic basis underlying parasite resistance traits in sheep. Following PRISMA guidelines, we identified 22 studies including 28,033 samples from 32 breeds across 11 countries, extracting 1580 candidate genes associated with resistance traits, including fecal egg count, packed cell volume, and immunoglobulin levels. Gene prioritization analysis using ToppGene identified 75 high-confidence candidate genes. Results: Functional enrichment analysis revealed significant involvement of the JAK-STAT signaling pathway, inflammatory response processes, and immune-related biological functions. Protein–protein interaction network analysis identified nine key hub genes: TNF, STAT3, STAT5A, PDGFB, ADRB2, MAPT, ITGB3, SMO, and GH1. The JAK-STAT pathway emerged as particularly important, with multiple core genes involved in cytokine signaling and immune cell development. These findings demonstrate that parasite resistance involves complex interactions between inflammatory responses, immune signaling networks, and metabolic processes. Conclusions: This comprehensive genetic framework provides essential insights for developing genomic selection strategies and marker-assisted breeding programs to enhance natural parasite resistance in sheep, offering a sustainable approach to reducing drug dependence and improving animal welfare in global sheep production systems. Full article

Tau protein, a neuron-enriched microtubule-associated protein encoded by the MAPT gene, plays pivotal roles in microtubule stabilisation, axonal transport, and synaptic plasticity. Aberrant post-translational modifications (PTMs), hyperphosphorylation, acetylation, ubiquitination, oxidative stress and neuroinflammation disrupt tau’s normal functions, drive its mislocalization, and promote aggregation into neurofibrillary tangles, a hallmark of Alzheimer’s disease (AD) and related tauopathies. Over the past two decades, tau-targeted therapies have advanced into clinical development, yet most have failed to demonstrate efficacy in human trials. This review synthesises mechanistic insights into tau biology and pathology, highlighting phosphorylation and acetylation pathways, aggregation-prone motifs, and immune-mediated propagation. We analyse the current therapeutic landscape, including kinase and phosphatase modulators, O-GlcNAcase inhibitors, aggregation blockers, immunotherapies, and microtubule-stabilising agents, while examining representative clinical programs and the reasons underlying their limited success. By combining mechanistic understanding with clinical experience, this review outlines emerging opportunities for rational treatment development, aiming to inform future tau-targeted strategies for AD and other tauopathies. Full article

This study investigated the regulatory role of the long non-coding RNA maternally expressed gene 3 (MEG3) in tau hyperphosphorylation and insulin signaling (PI3K/AKT1/GSK3β) under high-glucose (HG)-induced neurotoxic conditions mimicking Alzheimer’s disease pathology. To explore the function of MEG3 within a hyperglycemic (Hyp) model, MEG3 was silenced using small interfering RNA (siRNA) assay, followed by Western blot analysis, qRT-PCR, and network analyses. The siMEG3 + Hyp group had lower levels of AKT1 (0.48-fold) and PI3K (0.52-fold) than did the Hyp group. In the siMEG3 + Hyp group, GSK3β (2.51-fold) and TNFα (2.38-fold) expressions were higher than were those in the Hyp group, while in the siMEG3 group, GSK3β (4.59-fold), microtubule-associated protein TAU (MAPT, TAU) (6.37-fold), interleukin (IL)1β (5.67-fold), IL6 (3.29-fold), and tumor necrosis factor-α (TNFα) (3.06-fold) were all significantly upregulated in comparison to the control group. A higher level of p-tau protein was seen in the siMEG3 group in comparison to the control group, as well as in the siMEG3 + Hyp group in comparison to the Hyp group. Gene ontology analysis following MEG3 administration showed that genes downstream of the PI3K pathway were suppressed, whereas genes regulating the neuroinflammatory response were upregulated. The results suggest that the lncRNA MEG3 may be a promising therapeutic target in HG-induced neurodegenerative AD. Full article

The presence of cognitive lapses in the post-COVID-19 period, particularly among younger individuals, suggests a potential genetic predisposition. This case–control study aimed to assess the association between neurodegeneration-associated genes and cognitive declines in the post-COVID-19 Armenian population under the age of 65. In addition, we examined other contributing factors, including depressive symptoms, hypovitaminosis D, vitamin B12 and B9 deficiencies, and some viral infections, as potential confounders or effect modifiers. A total of 162 participants (ages 19–65, Med = 43), who were exposed to SARS-CoV-2 in Armenia between 2020 and 2022, participated in this study. Standardized assessments, including the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and the Montreal Cognitive Assessment (MoCA), were used to evaluate cognitive functions and mental status, while the Patient Health Questionnaire-9 (PHQ-9) was utilized to assess depressive symptoms. Clinical interview data, comprising yes/no self-reports regarding the presence of cognitive problems and depressive symptoms, were also included. Genetic analysis identified copy number variations (CNVs) in the APP, PSEN1, PSEN2, MAPT, and GRN genes, while viral infections (HSV-1, HSV-2, CMV, EBV, HIV, SARS-CoV-2, Hepatitis A, B, and C) and vitamin D, B12, and B9 deficiencies were measured. Lower cognitive performance was associated with CNVs in PSEN1 (exons 1, 9, 12), GRN (exons 1, 6, 12), and MAPT (exons 2, 8), along with viral infections (HSV-1, HSV-2, HAV-2). The findings indicate that post-COVID-19 cognitive problems are multifactorial and are linked to genetic mutations, viral infections, age, gender, and folic acid deficiency. Full article

Determining the genetic variations of candidate genes in affected subjects will help identify early pathological biomarkers of Alzheimer’s disease (AD) and develop effective treatments. It has recently been found that some genes that are linked share an increase in intron retention (IR). In this review, we discuss a few instances of mRNA-IR in various genes linked to AD, including APOE, MAPT-Tau, Psen2, Farp1, Gpx4, Clu, HDAC4, Slc16a3, and App genes. These genes are vulnerable to IR, encompassing additional crucial proteins for brain functionality, but they are frequently involved in pathways linked to the control of mRNA and protein homeostasis. Despite the advancements in human in vivo RNA therapy, as far as we know, there are no reports of data generated regarding artificial in vivo splicing in either animal models or humans. To prevent genetic variations and improve or repair errors in expression of desired genes, humans have adopted new gene editing techniques like CRISPR-Cas9 and RNAi modalities. Ultimately, IR could be utilized as a therapeutic potential biomarker for disorders related to intronic expansion. Full article

Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are linked by shared genetic mutations and overlapping clinical features, forming a clinical spectrum. This systematic review and meta-analysis analysed 97 studies, including 3212 patients with key ALS/FTD gene mutations, to identify gene-specific behavioural profiles. Chromosome 9 open reading frame 72 (C9orf72) mutations were strongly associated with psychotic symptoms and aggression, while superoxide dismutase 1 (SOD1) mutations had minimal cognitive effects. Progranulin (PGRN) mutations correlated with apathy and hallucinations, microtubule-associated protein tau (MAPT) mutations with disinhibition, and charged multivesicular body protein 2B (CHMP2B) with social impairments. Fused in sarcoma (FUS) mutations caused early sleep disturbances, TANK-binding kinase 1 (TBK1) led to disinhibition, and presenilin 1 and 2 (PSEN1/2) was linked to severe aggression. Prodromal cognitive changes in PGRN, MAPT, and CHMP2B mutations suggested early disease onset. Despite overlapping symptoms and clinical heterogeneity, understanding gene-specific patterns could inform tailored care strategies to enhance the quality of life for ALS and FTD patients. This study calls for refined guidelines integrating genetic behavioural profiles to improve patient and family support. Full article

Background: Progressive Supranuclear Palsy (PSP) is a rare neurodegenerative disorder characterized by abnormal tau protein aggregation. The MAPT gene encodes for tau protein. The MAPT locus harbors two major haplotypes, H1 and H2, with H1 and its subhaplotypes being associated with an increased risk of PSP. Methods: In this study, we genotyped rs8070723 in a cohort of 73 PSP patients, including 47 PSP Richardson Syndrome (PSP-RS) and 27 PSP variants (vPSP), and 93 age-matched healthy controls (HC) from Southern Italy. Results: Haplotype analysis identified H1 and H2 haplotypes that conferred a risk (OR, 2.620; 95% CI, 1.399–5.140; p = 0.0035) and a protective effect (OR, 0.370; 95% CI, 0.196–0.695; p = 0.0015), respectively. In addition, we genotyped five MAPT variants (rs1467967, rs242557, rs3785883, rs2471738, and rs7521) that, together with rs8070723, defined H1 subhaplotypes. We identified 18 distinct MAPT H1 subhaplotypes, among which H1j displayed a nominally significant reduced risk of PSP (OR, 0.201; 95% CI, 0.044–0.915; p = 0.0265). Conclusions: These findings reinforce the role of MAPT genetic variation in PSP pathogenesis and highlight the potential impact of haplotype diversity on disease susceptibility. Full article

Tau protein plays a pivotal role in maintaining neuronal structure and function through its regulation of microtubule stability and neuronal polarity. Encoded by the MAPT gene, Tau exists in multiple isoforms due to alternative mRNA splicing, with differential expression in the central and peripheral nervous systems. In healthy neurons, tau mRNA is selectively localized and translated in axons, a process tightly regulated by untranslated regions (UTRs) and RNA-binding proteins such as HuD and FMRP. Pathologically, Tau undergoes hyperphosphorylation, misfolding, and aggregation, which contribute to neurodegeneration in a range of disorders collectively known as tauopathies. Alzheimer’s disease (AD) is the most prevalent tauopathy, where abnormal Tau accumulation in the temporal and frontal lobes correlates with cognitive decline and behavioral symptoms. Other tauopathies, including Progressive Supranuclear Palsy (PSP), Corticobasal Degeneration (CBD), Frontotemporal Dementia with Parkinsonism (FTDP-17), and Pick’s disease, are distinguished by the predominance of specific Tau isoforms (3R or 4R), cellular distribution, and affected brain regions. Notably, astroglial tauopathies highlight the pathological role of Tau accumulation in glial cells, expanding the understanding of neurodegeneration beyond neurons. Despite advances in imaging biomarkers (e.g., Tau-PET) and molecular diagnostics, effective disease-modifying therapies for tauopathies remain elusive. Ongoing research targets Tau through immunotherapies, splicing modulators, kinase inhibitors, and antisense oligonucleotides, aiming to mitigate Tau pathology and its deleterious effects. Understanding the multifaceted roles of Tau in neuronal and glial contexts is critical for developing future therapeutic strategies against tauopathies. Full article

Progressive supranuclear palsy (PSP) is a neurodegenerative disease, classified as an atypical Parkinsonian syndrome, that has been pathologically and clinically defined. The histopathological aspects of the disease include tufted astrocytes, while the clinical features involve oculomotor dysfunction, postural instability, akinesia, cognitive impairment, and language difficulties. Although PSP is generally considered a sporadic disease, interest is growing in its genetics, with contemporary research focusing on familial backgrounds and neuroinflammation. Indeed, microglial activation and other inflammatory mechanisms of PSP pathogenesis have been extensively analyzed using genetic examinations to identify the factors impacting neurodegeneration. As such, this review aims to elaborate on recent findings in this field. Full article

Background: Tauopathy has been identified as a prevalent causative agent of neurodegenerative diseases, including frontotemporal dementia with parkinsonism-17 (FTDP-17). This rare hereditary neurodegenerative condition is characterised by the manifestation of parkinsonism and behavioural changes. The majority of cases of FTDP-17 are associated with mutations in the MAPT gene, which encodes the tau protein. MAPT mutations lead to disruption of the balance between 3R and 4R tau forms, which causes destabilisation of microtubules and impairment of cellular organelle functions, particularly mitochondrial dysfunction. The development of model systems and tools for studying the molecular, genetic, and biochemical mechanisms underlying FTDP-17 and testing therapies at the cellular level is an urgent necessity. Methods: In this study, we generated transgenic lines of induced pluripotent stem cells (iPSCs) from a patient carrying the pathogenic mutation c.2013T > G (rs63750756, p.N279K) of MAPT and a healthy donor. A doxycycline-controlled transgene of the genetically encoded biosensor MitoTimer was integrated into the AAVS1 locus of these cells. The MitoTimer biosensor allows for lifetime monitoring of the turnover of mitochondria in neuronal cells derived from directed iPSC differentiation. The fact that transcription of the transgene can be induced by doxycycline provides additional possibilities for pulse labelling of newly formed mitochondria. Results: Transgenic iPSC lines provide a unique tool to study the molecular and genetic mechanisms of FTDP-17 caused by the presence of the c.2013T > G (p.N279K) mutation, as well as to test potential drugs in vitro. Full article

Alzheimer’s disease (AD) prevention is a critical challenge for aging societies, necessitating the exploration of food ingredients and whole foods as potential therapeutic agents. This study aimed to identify natural compounds (NCs) with therapeutic potential in AD using an innovative bioinformatics-integrated deep neural analysis approach, combining computational predictions with molecular docking and in vitro experiments for comprehensive evaluation. We employed the bioinformatics-integrated deep neural analysis of NCs for Disease Discovery (BioDeepNat) application in the data collected from chemical databases. Random forest regression models were utilized to predict the IC₅₀ (pIC₅₀) values of ligands interacting with AD-related target proteins, including acetylcholinesterase (AChE), amyloid precursor protein (APP), beta-secretase 1 (BACE1), microtubule-associated protein tau (MAPT), presenilin-1 (PSEN1), tumor necrosis factor (TNF)-α, and valosin-containing protein (VCP). Their activities were then validated through a molecular docking analysis using Autodock Vina. Predictions by the deep neural analysis identified 166 NCs with potential effects on AD across seven proteins, demonstrating outstanding recall performance. The top five food sources of these predicted compounds were black walnut, safflower, ginger, fig, corn, and pepper. Statistical clustering methodologies segregated the NCs into six well-defined groups, each characterized by convergent structural and chemical signatures. The systematic examination of structure–activity relationships uncovered differential molecular patterns among clusters, illuminating the sophisticated correlation between molecular properties and biological activity. Notably, NCs with high activity, such as astragalin, dihydromyricetin, and coumarin, and medium activity, such as luteolin, showed promising effects in improving cell survival and reducing lipid peroxidation and TNF-α expression levels in PC12 cells treated with lipopolysaccharide. In conclusion, our findings demonstrate the efficacy of combining bioinformatics with deep neural networks to expedite the discovery of previously unidentified food-derived active ingredients (NCs) for AD intervention. Full article

The term frontotemporal dementia (FTD) comprises a group of neurodegenerative disorders characterized by the progressive degeneration of the frontal and temporal lobes of the brain with language impairment and changes in cognitive, behavioral and executive functions, and in some cases motor manifestations. A high proportion of FTD cases are due to genetic mutations and inherited in an autosomal-dominant manner with variable penetrance depending on the implicated gene. Iron is a crucial microelement that is involved in several cellular essential functions in the whole body and plays additional specialized roles in the central nervous system (CNS) mainly through its redox-cycling properties. Such a feature may be harmful under aerobic conditions, since it may lead to the generation of highly reactive hydroxyl radicals. Dysfunctions of iron homeostasis in the CNS are indeed involved in several neurodegenerative disorders, although it is still challenging to determine whether the dyshomeostasis of this essential but harmful metal is a direct cause of neurodegeneration, a contributor factor or simply a consequence of other neurodegenerative mechanisms. Unlike many other neurodegenerative disorders, evidence of the dysfunction in brain iron homeostasis in FTD is still scarce; nonetheless, the recent literature intriguingly suggests its possible involvement. The present review aims to summarize what is currently known about the contribution of iron dyshomeostasis in FTD based on clinical, imaging, histological, biochemical and molecular studies, further suggesting new perspectives and offering new insights for future investigations on this underexplored field of research. Full article

As the global population ages, the rising prevalence of neurodegenerative diseases, characterized by abnormal protein aggregates, presents significant challenges for early diagnosis and disease monitoring. Identifying accessible tissue biomarkers is crucial for advancing our ability to detect and track the progression of these diseases. Among the most promising biomarkers is the skin, which shares a common embryological origin with the brain and central nervous system (CNS). This biological connection positions the skin as a potential reflection of CNS pathology. Over the past decades, gene expression studies have demonstrated that key genes involved in neurodegenerative diseases are also expressed in skin tissues. Genes such as APP, PSEN1, PPA2, PINK1, LRRK2, PLCB4, MAPT, SPAST, and SPG7 are prominent in this regard. Beyond gene expression, proteins related to neurodegenerative diseases—such as α-synuclein, TAU, PARKIN, and prion protein (PrP)—have been isolated from the skin of affected individuals, underscoring the skin’s capacity to mirror neural degeneration. This non-invasive window into neurodegenerative processes is further enhanced by advances in stem cell technology, which have allowed for the generation of human-induced pluripotent stem cells (iPSCs) from patient-derived fibroblasts. These iPSCs offer a valuable model for studying disease mechanisms and developing therapeutic approaches. This review conducts a comprehensive analysis of the literature from databases such as PubMed, Google Scholar, and ResearchGate, emphasizing the unique potential of the skin as a non-invasive biomarker for neurodegenerative diseases. It explores how the skin serves as a bridge between gene expression and disease pathology in both the skin and the CNS. By leveraging this biological connection, the skin emerges as a promising model for enhancing our understanding of neurodegenerative disorders and developing innovative strategies for early detection and treatment. However, significant limitations remain, requiring further validation to establish the specificity and sensitivity of these biomarkers. Full article