Synthesis, biological evaluation and mechanism study of 2-benzoyl-quinazolinone derivative as ferroptosis inhibitor for the treatment of Parkinson's disease.

Neurodegenerative diseases, including Alzheimer's disease and Parkinson's disease, represent an escalating global health burden owing to their complex pathophysiology and limited therapeutic options. Exosomes, nanoscale extracellular vesicles (30-150 nm) capable of crossing the blood-brain barrier (BBB), have emerged as critical mediators of intercellular communication in the central nervous system. While research has predominantly focused on exosomal proteins and nucleic acids, the functional significance of exosomal lipids in neurodegeneration is increasingly recognized. This review outlines the biological characteristics of exosome lipids. Then, we focus on three core mechanisms: how lipid imbalance drives neuronal damage (including membrane dysfunction, lipid peroxidation, and mitochondrial energy crisis), how the lipid-mediated inflammatory network regulates microglial activation and BBB integrity, and how the lipid microenvironment affects the folding, aggregation, and cross-cell transmission of pathological proteins. Critically, these mechanisms form a mutually reinforcing vicious cycle, jointly driving the progression of the disease. Based on this framework, we have summarized the specific alterations of exosomal lipids in diseases such as Alzheimer's disease and Parkinson's disease. The clinical potential of exosomal lipids as liquid biopsy biomarkers and drug delivery carriers is discussed, alongside current challenges including technical standardization, heterogeneity analysis, and quantitative accuracy. A comprehensive understanding of exosomal lipid dynamics is essential for developing novel diagnostic and therapeutic strategies for neurodegenerative diseases.

Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease for which there is no cure. While the precise etiology of ALS remains elusive, growing evidence suggests a pathogenic role for human endogenous retrovirus-K (HERV-K) in ALS. Expression of HERV-K subtype HML-2 envelope protein in neurons causes neurotoxicity in vitro and induces ALS-like symptoms in mice. We investigated the use of the Adeno-Associated Virus-9 (AAV9)-mediated artificial microRNA (amiRNA) targeting the HML-2 env gene in an ALS mouse model. From an in vitro screen of amiRNAs targeting the HML-2 env gene three were chosen and inserted in tandem into an AAV9 vector and validated in vitro. This approach provided robust silencing of the transgene, with tandem amiRNA achieving robust reduction in gene and protein expression levels. Its therapeutic effectiveness was tested in an HML-2 Env transgenic mouse model in which the env gene is expressed under the neuron-specific thy1 promoter and develops an ALS-like phenotype. A single intracerebroventricular injection of AAV9 vector encoding the amiRNAs into the mice at postnatal day 1 effectively reduced HML-2 Env expression in the brain and spinal cord at 84 days post-injection which was the longest time point studied. Knockdown of HML-2 env decreased the loss of cortical and spinal motor neurons and alleviated muscle fiber degeneration and fiber type grouping. This led to improved motor function. Our results provide compelling evidence supporting the use of multiple amiRNAs delivered in an AAV9 vector for treating forms of ALS linked to HML-2.

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease with multifactorial causes, including genetic and environmental factors. This study aimed to identify environmental and lifestyle factors influencing the progression of ALS by leveraging the first and largest patient-reported ALS database in China (the AskHelpU ALS Patient Platform), addressing a critical gap in regional research. Data from 1421 patients with ALS, including detailed information on occupational exposure, lifestyle habits, dietary patterns, and medical history, were collected from the AskHelpU platform. Statistical analyses were conducted to identify associations between these factors and clinical characteristics. The associations between pre-onset factors and disease progression were analyzed using multicariable generalized linear models, adjusting for multiple comaparisons with the Bonferroni correction. Employment in the agriculture industry (p < 0.001) was associated with rapid ALS progression, whereas employment in the leasing and business services industry (p = 0.01) and education industry (p = 0.033) slowed ALS progression. Other key pre-onset prognostic factors were cigarette smoking (p = 0.043) and pre-existing hypertension (p = 0.036). By utilizing the patient-reported ALS database, this study comprehensively examined the effects of environmental, occupational, and lifestyle factors on ALS progression. These findings provide novel insights into the regional variations in ALS etiology, emphasizing the multifactorial nature of the disease.

Neuroinflammation is a pathological feature of neurodegenerative diseases like Alzheimer's disease and ALS. Cytoplasmic dsRNA (cdsRNA) triggers a type-I interferon response in human neural cells, leading to their death, and is found in neurons of C9ORF72-ALS patients. Here, we report the spatial coincidence of cdsRNA and pTDP-43 inclusions in human postmortem tissue with Alzheimer's disease pathology, and upregulated interferon response genes in affected regions. CdsRNA also accumulates in a human TDP-43 G298S iPSC cortical neuronal model. We use cryptic exon detection as a proxy for TDP-43 mislocalization and demonstrate that FDA-approved JAK inhibitors baricitinib and ruxolitinib, which block interferon signaling, show protective effects only in brains with elevated cryptic exon expression. A CRISPR screen reveals TYK2 as a top hit, and TYK2 knockdown and the selective TYK2 inhibitor deucravacitinib rescue cdsRNA-induced toxicity. We find parallel neuroinflammatory mechanisms, dependent on TYK2 - a potential disease-modifying target - for TDP-43-associated Alzheimer's disease and C9ORF72-ALS.

Parkinson's disease (PD) is the second most common neurodegenerative disease withmovement disorder. The etiology and molecular pathogenesis of PD are not fully understood. Mutations in the LRRK2 gene are the primary genetic causes of PD and contribute to sporadic PD. Mitochondrial dysfunction and neuroinflammation have been reported in LRRK2-based PDmodels. However, the molecular mechanisms in LRRK2-linked PD remain largely unknown. In this study, we used a human microglial cell line (HMC-3) to study the effects of mutant LRRK2-R1441G and a mitochondrial toxin (MPP+), on microglial activation and its linked gene and pathway changes using RNA sequencing combined with biological assays. We found that mutant LRRK2-R1441G with MPP+ exposure induced M1 rather than M2 microglial activation by activating the interferon signaling pathway and reducing miR-146a-5p function thereby elevating its targeted genes, such as Stat1, and reducing Nrf2 levels to inhibit neuroinflammation. Whereas treatment of LRRK2 kinase inhibitor or elevated miR-146a-5p could promote the shift of microglia from M1 to M2 activation by correcting interferon signaling and/or restoring the miR-146a-5p levels, reducing Stat1 and increasing Nrf2 levels thereby inhibiting neuroinflammation. Our findings not only provide novel insights into the mechanisms of LRRK2 regulating microglial activation underlying neuroinflammation in PD pathogenesis but also validate that targeting LRRK2 and/or miR-146a-5p could be potential novel treatment strategies for PD and other LRRK2-linked neuroinflammatory disorders.

Canine degenerative myelopathy (DM) is an adult-onset neurodegenerative disease considered a spontaneous model of human amyotrophic lateral sclerosis (ALS). Neuroinflammation occurs in both DM and ALS, and crosstalk between the central nervous system and systemic immunity has been demonstrated in ALS. To investigate this interaction in DM, we analyzed peripheral blood and spinal cord tissues using real-time RT-PCR and immunofluorescence. In peripheral blood, mRNA expression of interleukin (IL)-18 and nod-like receptor protein 3 was significantly increased compared with intervertebral disk herniation controls. IL-10 and caspase-1 were elevated, whereas tumor necrosis factor-α was decreased relative to healthy controls. C-C motif chemokine receptor 2 expression showed a moderate negative correlation with disease duration. Immunofluorescence revealed a few transmembrane protein 119- and mannose receptor C-type 1+ cells, indicating limited infiltration of peripheral blood-derived macrophages into the spinal cord. Transcriptional analysis of spinal cords with different degrees of degeneration showed increased expression of activated astrocyte markers (serping1 and S100A10) and C-C motif chemokine ligand 2 in moderately to severely degenerated tissues. Furthermore, immunohistochemical analysis revealed increased CCL2 protein expression in the affected spinal cords. These findings suggest that systemic immune activation contributes to spinal neuroinflammation in DM, although its limited cellular infiltration implies a minor role in neurodegeneration.

Neurofibrillary tangles (NFTs) formed from the protein tau disrupt neuronal function in Alzheimer's disease and are strongly associated with cognitive decline. Early events in tau aggregation are increasingly linked to the formation of biomolecular condensates, which lower the energetic barriers to pathological aggregation by acting as intermediates that transition into insoluble assemblies, a mechanism also implicated in other neurodegenerative diseases, such as amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Despite growing evidence for this pathway, the molecular basis by which reversible condensates evolve into irreversible, pathogenic aggregates has remained unclear. Here, we map the phase behavior, structural transitions, and thermodynamic reversibility of tau during condensate aging. Our results reveal that the two hallmark features of the pathological end state, β-sheet enrichment and irreversible aggregation, emerge at different rates and occupy distinct regions of the phase space, indicating that these properties are mechanistically uncoupled. Notably, we identify tau condensate phases that are β-sheet rich yet thermodynamically reversible, as well as irreversible intermediates that lack β-sheet structure. These findings expand the landscape of tau aggregate species beyond a simple linear progression toward fibrils and highlight a diverse array of intermediates with distinct structural and thermodynamic properties. This decoupling of structure and irreversibility has important implications for understanding tau aggregation mechanisms and may offer targets for therapeutic intervention.

Neurodegenerative diseases, like Alzheimer's disease (AD), are characterized by the accumulation of tau aggregates, leading to neuronal dysfunction and cognitive decline. This study explores the development of dual-acting compounds combining sigma-1 receptor (σ1R) agonists and histone deacetylase inhibitors (HDACi) to target these pathological mechanisms. Compounds 2d and 3a demonstrated high affinity for σ1R and significantly reduced tau aggregation and phosphorylation in vitro, notably at the AT8 epitope. These dual-acting compounds destabilized tau aggregates, increased tau solubility, and showed favorable pharmacokinetic properties, with compound 2d exhibiting enhanced chemical stability and longer half-life than 3a. In vivo, both compounds confirmed a σ1R agonist profile by reversing the effect of the σ1R antagonist BD-1063. This dual-action approach, acting on both HDAC and σ1R pathways, holds significant potential for treating tauopathies. While further optimization and clinical evaluation are needed, these findings provide a strong foundation for the continued development of multimodal therapies for neurodegenerative diseases treatment.

Traumatic optic neuropathy (TON) is a devastating cause of irreversible vision loss for which no effective treatment currently exists. Its poor prognosis stems from two major challenges: the limited regenerative capacity of retinal ganglion cells (RGCs) and the hostile, inflammation-driven environment that follows injury. In this work, using transcriptomic bioinformatic and histopathological analysis, we discovered that mechanical trauma and subsequent neuroinflammation trigger microglial pyroptosis through the NLRP3/CASP1/GSDMD pathway. This process amplifies inflammatory cascades and exacerbates RGC degeneration via microglia-neuron interactions. To overcome these dual barriers, we engineered a microglia-targeted lipid nanoparticle (LNP) platform co-delivering disulfiram (DSF), a selective GSDMD inhibitor, together with self-amplifying mRNA (saRNA) encoding ciliary neurotrophic factor (CNTF). We found that this combinatorial strategy concurrently suppresses pyroptosis-driven neuroinflammation while providing sustained neurotrophic support. Through comprehensive in vitro and in vivo evaluations, the co-delivery system showed enhanced RGC survival, remarkable axonal regeneration, and eventually significant restoration of visual function. In summary, our results demonstrate that a coordinated strategy targeting both neuroinflammatory mechanisms and regenerative pathways yields superior therapeutic outcomes in TON. This work underscores the potential of integrated RNA-small molecule therapies as a promising multi-target treatment paradigm, with broad applicability for other neuroinflammatory and neurodegenerative diseases.

Plant-based models of neurodegenerative CAG repeat expansion diseases.

The gut-brain axis is increasingly recognized as a critical contributor to Parkinson's disease (PD) pathogenesis, yet the therapeutic impact of microbiota modulation remains unclear due to lack of clinical trials in drug-naïve patients. We conducted a randomized, double-blind, placebo-controlled phase 2 trial to evaluate the safety, tolerability, and efficacy of repeated donor fecal microbiota transplantation (dFMT) in de novo PD. FMT was administered for seven days (200 mL on days 1-3; 50 mL on days 4-7) per 4-week cycle. Seventy-two patients were randomized 1:1 to receive dFMT or autologous FMT (aFMT), and 66 completed the trial. At 35 weeks, the dFMT group showed significant improvement in motor symptoms (mean change in Unified Parkinson's Disease Rating Scale [UPDRS] III: -3.8 vs. +0.1; p = 0.0001) and a substantially greater reduction in constipation severity (dFMT vs. aFMT: -6.5 vs. -0.7; p < 0.0001), accompanied by improved quality-of-life scores. Microbiome profiling revealed greater similarity to donor composition and a marked reduction in Escherichia-Shigella, correlating with decreased colonic α-synuclein aggregation (r = 0.3775, p = 0.0277), supporting a gut-brain mechanistic link. Biochemical analyses showed elevated fecal dopamine and 3,4-dihydroxyphenylacetic acid levels, while histological assessments demonstrated strengthened epithelial barrier integrity with increased E-cadherin expression. All adverse events were mild and self-limited; no serious treatment-related events were observed. These findings demonstrate that repeated dFMT is safe, well tolerated, and yields clinically meaningful motor and gastrointestinal improvements in drug-naïve PD, providing integrated mechanistic and clinical evidence that microbiota-targeted modulation represents a promising nonpharmacologic therapeutic strategy for neurodegenerative disease. Trial registration: Chinese Clinical Trial Registry, ChiCTR2200064151.

Neurodegenerative diseases are a major threat to global public health. Recent studies have revealed that mitochondrial DNA damage and the imbalance of protein homeostasis during aging constitute the core pathological basis of neurodegeneration. The resulting energy metabolism disorders are the common pathogenic hubs of multiple neurodegenerative diseases. In this review, we focus on representative neurodegenerative diseases, including Parkinson's disease, Alzheimer's disease, and Huntington's disease, and systematically discuss their pathology related to metabolic disorders. We introduce various energy compensation strategies: (1) rebuilding the energy supply by enhancing mitochondrial function; (2) implementing systemic metabolic remodeling; (3) supplementing alternative energy substrates; (4) utilizing direct energy delivery technology. This review also highlights the technical bottlenecks of existing energy compensation strategies, guiding future research on neurodegenerative diseases.

Atypical frontotemporal lobar degeneration with ubiquitin-positive inclusions (aFTLD-U) is neuropathologically characterized by aggregation of the FET family of proteins and clinically manifests as sporadic young-onset frontotemporal dementia. Here we describe a major risk locus on chr15q14 identified through a genome-wide association study in 59 pathologically confirmed aFTLD-U cases and 3,153 controls (lead single nucleotide polymorphism rs549846383, P = 5.85 × 10-21, odds ratio 26.7). When combined with data from 28 additional aFTLD-U cases, 3,712 controls and 3,215 individuals with other neurodegenerative diseases and by leveraging in-house and public long-read genome sequencing data from 1,715 individuals, we identified a tandem repeat expansion on the associated haplotypes in an intron of GOLGA8A. We found variation in repeat length, motif length, and motif sequence, with long CT-dimer expansions strongly associated with aFTLD-U. Although the functional consequence of this repeat remains unknown, its presence in nearly 60% of aFTLD-U cases points to a fundamental role in disease pathogenesis.

Hydrophobic interfaces are ubiquitous, and interactions of proteins with such surfaces remain an area of significant interest. α-Synuclein (α-Syn), a protein abundant in cerebrospinal fluid, is implicated in nearly 50 neurological disorders. The misfolding of α-Syn into amyloid aggregates is a critical step in the progression of several neurodegenerative diseases. Hydrophobic interfaces have been shown to catalyze this process. To better understand the mechanism of aggregation and ultimately aid in the development of therapeutic strategies, it is essential to probe the interfacial structures of α-Syn that may drive amyloid formation. Here, we present a detailed investigation of the interfacial structure of α-Syn on a polystyrene (PS) film, a widely used material in consumer products and laboratory settings. Elucidating the structural motifs of α-Syn at the PS interface provides insights into how plastic contaminants may induce conformational changes in the protein. Combining experimental vibrational sum frequency generation spectroscopy with theoretical spectral calculations, we identify the interfacial structure of α-Syn at the PS film and compare it with previously reported α-Syn conformation on air-water interfaces. The entire NAC region and majority of the residues in the N terminal are in direct contact with the PS surface, while the C terminal residues protrude away from the interface, staying in the solution. Our studies highlight the critical role of polymeric surfaces in facilitating α-Syn misfolding.

The stress responsive transcription factor ATF4: from molecular structure to disease mechanisms.

Microglia use a highly complex and dynamic network of branched processes to sense and respond to their surroundings. Despite emerging evidence that microglial motility plays important roles in brain development, neurodegeneration, and neuropsychiatric disease, little is known about the intracellular machinery orchestrating microglial process dynamics. Here, we identify roles for regulators of the actin cytoskeleton in controlling microglial behavior. We show that the actin branching Arp2/3 complex is critical for maintaining microglial morphology and is required for surveillance but not chemotactic motility. Neuropsychiatric disease-associated CYFIP1, a core component of the WAVE regulatory complex linking upstream signaling pathways to activation of the Arp2/3 complex, is highly expressed in microglia but has an unknown function. We report that conditional deletion of Cyfip1 in mouse microglia reduces their morphological complexity and surveillance of the brain parenchyma, with no effect on chemotaxis. Deletion of Cyfip1 also increased microglial CD68 positive lysosome volume and engulfment of presynapses. Thus, actin remodeling by CYFIP1 and the Arp2/3 complex controls microglial dynamics and shifts microglia away from a homeostatic state with potential implications for neuropsychiatric disease.

An explainable framework for the relationship between dementia and metabolism patterns.

CSF1R-related disorder (CSF1R-RD) is a rare autosomal dominant neurodegenerative disease characterized by cognitive decline, motor dysfunction, psychiatric symptoms, and white matter abnormalities. It is caused by mutations in the CSF1R gene. Despite the identification of many pathogenic CSF1R variants, the molecular mechanisms behind neuropathogenesis in CSF1R-RD remain poorly understood due to the lack of disease modeling. This study focuses on a novel CSF1R mutation, T567M, located outside the tyrosine kinase domain, whose pathogenic impact has not been characterized. To gain molecular insights into the pathogenic mechanisms of the CSF1R-T567M mutation, we established an induced pluripotent stem cell (iPSC) model system consisting of mutant (CSF1R-MT) and CRISPR/Cas9-corrected isogenic control lines. Using these iPSCs, we generated iPSC-derived microglia (iMGL) and cerebral organoids (COs). Through RNA sequencing, we identified altered genes and pathways involved in neuroinflammation in MT iMGL. We then investigated microglial migration, phagocytosis, cytokine profiling, neurodevelopment, and synaptic function in iMGL and iMGL-CO co-culture to study the role of T567M mutation in CSF1R-RD. Our research revealed that the CSF1R-MT caused haploinsufficiency of CSF1R, reducing autophosphorylation of CSF1R at Tyr546 and activating autophagy. CSF1R-MT iMGL induced neuroinflammation, increased phagocytosis, and impaired migration. Transcriptomic analysis showed upregulation of immune activity and downregulation of synaptic function. Additionally, CSF1R-MT promoted proliferation, inhibited neural differentiation and maturation, and caused neurodevelopmental defects in COs. Whole-cell patch-clamp recordings indicated impaired synaptic function in CSF1R-MT COs. Furthermore, CSF1R-MT microglia impaired synaptic protein expression when co-cultured with CSF1R-MT COs. Collectively, our study provides detailed mechanistic insights into the pathogenesis driven by the CSF1R-T567M mutation, highlighting the critical role of CSF1R signaling in neural homeostasis. This isogenic iPSC model serves as a valuable platform for probing mutation-specific mechanisms and future therapeutic screening.

Evolutionary studies of disease-associated genes provide crucial insights into pathological mechanisms and potential therapeutic targets. Polyglutamine spinocerebellar ataxias (SCAs) are human neurodegenerative diseases caused by toxic expanded CAG repeats. Studies on SCA1 have shown that a paralog of the causing-gene can partially rescue protein function and alleviate the neuropathology. The most common SCA, Machado-Joseph disease (MJD/SCA3), caused by mutated ataxin-3 gene (ATXN3), has no treatment currently available. Its paralog ataxin-3 like (ATXN3L) remains largely unexplored. Here, we identify three new retrotransposition events of ATXN3: ATXN3L0 in Euarchontoglires, ATXN3L2 in Simiformes, and ATXN3L3 in Cercopithecidae, in addition to ATXN3L (herein called ATXN3L1) originated in Haplorrhini. ATXN3 and ATXN3L1 are both under purifying selection throughout primate evolution, maintaining about 70% of amino acid identity. Also, the high conservation of ATXN3L1 Josephin domain hints at functional redundancy with the parental disease-associated ATXN3. ATXN3L2 presents a remarkable nucleotide similarity to ATXN3 (79%) in an interrupted reading frame, which may produce a regulatory RNA. Conversely, ATXN3L0 is likely a non-functional retrocopy and ATXN3L3 is absent in humans with no relevance for the disease. The comparison of (CAG)n interruption patterns of the different paralogs in several primates elucidates the process leading to the currently observed pure long tracts in human ATXN3, responsible for disease when expanded. This study intends to pioneer the identification of new paralogs of SCA-associated genes and the use of phylogenetic analyses to explore their potential role for targeted therapies.